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authorGravatar Abseil Team <absl-team@google.com>2018-06-21 12:55:12 -0700
committerGravatar Shaindel Schwartz <shaindel@google.com>2018-06-22 08:55:41 -0400
commit4491d606df34c44efda47b6d17b605262f17e182 (patch)
tree5c5a2717289760c229fed502a6310d70ca4ed35a /absl/strings
parentd89dba27e35462d7457121b978fd79214205e686 (diff)
Export of internal Abseil changes.
-- 70f43a482d7d4ae4a255f17ca02b0106653dd600 by Shaindel Schwartz <shaindel@google.com>: Internal change PiperOrigin-RevId: 201571193 -- 93e6e9c2e683158be49d9dd1f5cb1a91d0c0f556 by Abseil Team <absl-team@google.com>: Internal change. PiperOrigin-RevId: 201567108 -- fbd8ee94fbe9f2448e5adf5e88706f9c8216048f by Juemin Yang <jueminyang@google.com>: str_format release PiperOrigin-RevId: 201565129 -- 387faa301555a8a888c4429df52734aa806dca46 by Abseil Team <absl-team@google.com>: Adds a defaulted allocator parameter to the size_type constructor of InlinedVector PiperOrigin-RevId: 201558711 -- 39b15ea2c68d7129d70cbde7e71af900032595ec by Matt Calabrese <calabrese@google.com>: Update the variant implementation to eliminate unnecessary checking on alternative access when the index is known or required to be correct. PiperOrigin-RevId: 201529535 -- adab77f1f7bb363aa534297f22aae2b0f08889ea by Abseil Team <absl-team@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 201458388 -- a701dc0ba62e3cadf0de14203415b91df4ee8151 by Greg Falcon <gfalcon@google.com>: Internal cleanup PiperOrigin-RevId: 201394836 -- 8a7191410b8f440fdfa27f722ff05e451502ab61 by Abseil Team <absl-team@google.com>: Import of CCTZ from GitHub. PiperOrigin-RevId: 201369269 GitOrigin-RevId: 70f43a482d7d4ae4a255f17ca02b0106653dd600 Change-Id: I8ab073b30b4e27405a3b6da2c826bb4f3f0b9af6
Diffstat (limited to 'absl/strings')
-rw-r--r--absl/strings/BUILD.bazel139
-rw-r--r--absl/strings/CMakeLists.txt117
-rw-r--r--absl/strings/internal/str_format/arg.cc399
-rw-r--r--absl/strings/internal/str_format/arg.h434
-rw-r--r--absl/strings/internal/str_format/arg_test.cc111
-rw-r--r--absl/strings/internal/str_format/bind.cc232
-rw-r--r--absl/strings/internal/str_format/bind.h189
-rw-r--r--absl/strings/internal/str_format/bind_test.cc131
-rw-r--r--absl/strings/internal/str_format/checker.h325
-rw-r--r--absl/strings/internal/str_format/checker_test.cc150
-rw-r--r--absl/strings/internal/str_format/convert_test.cc575
-rw-r--r--absl/strings/internal/str_format/extension.cc84
-rw-r--r--absl/strings/internal/str_format/extension.h406
-rw-r--r--absl/strings/internal/str_format/extension_test.cc65
-rw-r--r--absl/strings/internal/str_format/float_conversion.cc476
-rw-r--r--absl/strings/internal/str_format/float_conversion.h21
-rw-r--r--absl/strings/internal/str_format/output.cc47
-rw-r--r--absl/strings/internal/str_format/output.h101
-rw-r--r--absl/strings/internal/str_format/output_test.cc78
-rw-r--r--absl/strings/internal/str_format/parser.cc294
-rw-r--r--absl/strings/internal/str_format/parser.h291
-rw-r--r--absl/strings/internal/str_format/parser_test.cc379
-rw-r--r--absl/strings/str_format.h512
-rw-r--r--absl/strings/str_format_test.cc603
24 files changed, 6159 insertions, 0 deletions
diff --git a/absl/strings/BUILD.bazel b/absl/strings/BUILD.bazel
index 328f52f3..3e50d24a 100644
--- a/absl/strings/BUILD.bazel
+++ b/absl/strings/BUILD.bazel
@@ -492,3 +492,142 @@ cc_test(
"@com_github_google_benchmark//:benchmark_main",
],
)
+
+cc_library(
+ name = "str_format",
+ hdrs = [
+ "str_format.h",
+ ],
+ copts = ABSL_DEFAULT_COPTS,
+ deps = [
+ ":str_format_internal",
+ ],
+)
+
+cc_library(
+ name = "str_format_internal",
+ srcs = [
+ "internal/str_format/arg.cc",
+ "internal/str_format/bind.cc",
+ "internal/str_format/extension.cc",
+ "internal/str_format/float_conversion.cc",
+ "internal/str_format/output.cc",
+ "internal/str_format/parser.cc",
+ ],
+ hdrs = [
+ "internal/str_format/arg.h",
+ "internal/str_format/bind.h",
+ "internal/str_format/checker.h",
+ "internal/str_format/extension.h",
+ "internal/str_format/float_conversion.h",
+ "internal/str_format/output.h",
+ "internal/str_format/parser.h",
+ ],
+ copts = ABSL_DEFAULT_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":strings",
+ "//absl/base:core_headers",
+ "//absl/container:inlined_vector",
+ "//absl/meta:type_traits",
+ "//absl/numeric:int128",
+ "//absl/types:span",
+ ],
+)
+
+cc_test(
+ name = "str_format_test",
+ srcs = ["str_format_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format",
+ ":strings",
+ "//absl/base:core_headers",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_extension_test",
+ srcs = [
+ "internal/str_format/extension_test.cc",
+ ],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format",
+ ":str_format_internal",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_arg_test",
+ srcs = ["internal/str_format/arg_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format",
+ ":str_format_internal",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_bind_test",
+ srcs = ["internal/str_format/bind_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format_internal",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_checker_test",
+ srcs = ["internal/str_format/checker_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_convert_test",
+ size = "small",
+ srcs = ["internal/str_format/convert_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format_internal",
+ "//absl/numeric:int128",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_output_test",
+ srcs = ["internal/str_format/output_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format_internal",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
+ name = "str_format_parser_test",
+ srcs = ["internal/str_format/parser_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":str_format_internal",
+ "//absl/base:core_headers",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
diff --git a/absl/strings/CMakeLists.txt b/absl/strings/CMakeLists.txt
index cab2c456..3d30c72a 100644
--- a/absl/strings/CMakeLists.txt
+++ b/absl/strings/CMakeLists.txt
@@ -81,6 +81,58 @@ absl_library(
strings
)
+# add str_format library
+absl_library(
+ TARGET
+ absl_str_format
+ SOURCES
+ "str_format.h"
+ PUBLIC_LIBRARIES
+ str_format_internal
+ EXPORT_NAME
+ str_format
+)
+
+# str_format_internal
+ absl_library(
+ TARGET
+ str_format_internal
+ SOURCES
+ "internal/str_format/arg.cc"
+ "internal/str_format/bind.cc"
+ "internal/str_format/extension.cc"
+ "internal/str_format/float_conversion.cc"
+ "internal/str_format/output.cc"
+ "internal/str_format/parser.cc"
+ "internal/str_format/arg.h"
+ "internal/str_format/bind.h"
+ "internal/str_format/checker.h"
+ "internal/str_format/extension.h"
+ "internal/str_format/float_conversion.h"
+ "internal/str_format/output.h"
+ "internal/str_format/parser.h"
+ PUBLIC_LIBRARIES
+ str_format_extension_internal
+ absl::strings
+ absl::base
+ absl::numeric
+ absl::container
+ absl::span
+)
+
+# str_format_extension_internal
+absl_library(
+ TARGET
+ str_format_extension_internal
+ SOURCES
+ "internal/str_format/extension.cc"
+ "internal/str_format/extension.h"
+ "internal/str_format/output.cc"
+ "internal/str_format/output.h"
+ PUBLIC_LIBRARIES
+ absl::base
+ absl::strings
+)
#
## TESTS
@@ -347,3 +399,68 @@ absl_test(
PUBLIC_LIBRARIES
${CHARCONV_BIGINT_TEST_PUBLIC_LIBRARIES}
)
+# test str_format_test
+absl_test(
+ TARGET
+ str_format_test
+ SOURCES
+ "str_format_test.cc"
+ PUBLIC_LIBRARIES
+ absl::base
+ absl::str_format
+ absl::strings
+)
+
+# test str_format_bind_test
+absl_test(
+ TARGET
+ str_format_bind_test
+ SOURCES
+ "internal/str_format/bind_test.cc"
+ PUBLIC_LIBRARIES
+ str_format_internal
+)
+
+# test str_format_checker_test
+absl_test(
+ TARGET
+ str_format_checker_test
+ SOURCES
+ "internal/str_format/checker_test.cc"
+ PUBLIC_LIBRARIES
+ absl::str_format
+)
+
+# test str_format_convert_test
+absl_test(
+ TARGET
+ str_format_convert_test
+ SOURCES
+ "internal/str_format/convert_test.cc"
+ PUBLIC_LIBRARIES
+ str_format_internal
+ absl::numeric
+)
+
+# test str_format_output_test
+absl_test(
+ TARGET
+ str_format_output_test
+ SOURCES
+ "internal/str_format/output_test.cc"
+ PUBLIC_LIBRARIES
+ str_format_extension_internal
+)
+
+# test str_format_parser_test
+absl_test(
+ TARGET
+ str_format_parser_test
+ SOURCES
+ "internal/str_format/parser_test.cc"
+ PUBLIC_LIBRARIES
+ str_format_internal
+ absl::base
+)
+
+
diff --git a/absl/strings/internal/str_format/arg.cc b/absl/strings/internal/str_format/arg.cc
new file mode 100644
index 00000000..eafb068f
--- /dev/null
+++ b/absl/strings/internal/str_format/arg.cc
@@ -0,0 +1,399 @@
+//
+// POSIX spec:
+// http://pubs.opengroup.org/onlinepubs/009695399/functions/fprintf.html
+//
+#include "absl/strings/internal/str_format/arg.h"
+
+#include <cassert>
+#include <cerrno>
+#include <cstdlib>
+#include <string>
+#include <type_traits>
+
+#include "absl/base/port.h"
+#include "absl/strings/internal/str_format/float_conversion.h"
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+const char kDigit[2][32] = { "0123456789abcdef", "0123456789ABCDEF" };
+
+// Reduce *capacity by s.size(), clipped to a 0 minimum.
+void ReducePadding(string_view s, size_t *capacity) {
+ *capacity = Excess(s.size(), *capacity);
+}
+
+// Reduce *capacity by n, clipped to a 0 minimum.
+void ReducePadding(size_t n, size_t *capacity) {
+ *capacity = Excess(n, *capacity);
+}
+
+template <typename T>
+struct MakeUnsigned : std::make_unsigned<T> {};
+template <>
+struct MakeUnsigned<absl::uint128> {
+ using type = absl::uint128;
+};
+
+template <typename T>
+struct IsSigned : std::is_signed<T> {};
+template <>
+struct IsSigned<absl::uint128> : std::false_type {};
+
+class ConvertedIntInfo {
+ public:
+ template <typename T>
+ ConvertedIntInfo(T v, ConversionChar conv) {
+ using Unsigned = typename MakeUnsigned<T>::type;
+ auto u = static_cast<Unsigned>(v);
+ if (IsNeg(v)) {
+ is_neg_ = true;
+ u = Unsigned{} - u;
+ } else {
+ is_neg_ = false;
+ }
+ UnsignedToStringRight(u, conv);
+ }
+
+ string_view digits() const {
+ return {end() - size_, static_cast<size_t>(size_)};
+ }
+ bool is_neg() const { return is_neg_; }
+
+ private:
+ template <typename T, bool IsSigned>
+ struct IsNegImpl {
+ static bool Eval(T v) { return v < 0; }
+ };
+ template <typename T>
+ struct IsNegImpl<T, false> {
+ static bool Eval(T) {
+ return false;
+ }
+ };
+
+ template <typename T>
+ bool IsNeg(T v) {
+ return IsNegImpl<T, IsSigned<T>::value>::Eval(v);
+ }
+
+ template <typename T>
+ void UnsignedToStringRight(T u, ConversionChar conv) {
+ char *p = end();
+ switch (conv.radix()) {
+ default:
+ case 10:
+ for (; u; u /= 10)
+ *--p = static_cast<char>('0' + static_cast<size_t>(u % 10));
+ break;
+ case 8:
+ for (; u; u /= 8)
+ *--p = static_cast<char>('0' + static_cast<size_t>(u % 8));
+ break;
+ case 16: {
+ const char *digits = kDigit[conv.upper() ? 1 : 0];
+ for (; u; u /= 16) *--p = digits[static_cast<size_t>(u % 16)];
+ break;
+ }
+ }
+ size_ = static_cast<int>(end() - p);
+ }
+
+ const char *end() const { return storage_ + sizeof(storage_); }
+ char *end() { return storage_ + sizeof(storage_); }
+
+ bool is_neg_;
+ int size_;
+ // Max size: 128 bit value as octal -> 43 digits
+ char storage_[128 / 3 + 1];
+};
+
+// Note: 'o' conversions do not have a base indicator, it's just that
+// the '#' flag is specified to modify the precision for 'o' conversions.
+string_view BaseIndicator(const ConvertedIntInfo &info,
+ const ConversionSpec &conv) {
+ bool alt = conv.flags().alt;
+ int radix = conv.conv().radix();
+ if (conv.conv().id() == ConversionChar::p)
+ alt = true; // always show 0x for %p.
+ // From the POSIX description of '#' flag:
+ // "For x or X conversion specifiers, a non-zero result shall have
+ // 0x (or 0X) prefixed to it."
+ if (alt && radix == 16 && !info.digits().empty()) {
+ if (conv.conv().upper()) return "0X";
+ return "0x";
+ }
+ return {};
+}
+
+string_view SignColumn(bool neg, const ConversionSpec &conv) {
+ if (conv.conv().is_signed()) {
+ if (neg) return "-";
+ if (conv.flags().show_pos) return "+";
+ if (conv.flags().sign_col) return " ";
+ }
+ return {};
+}
+
+bool ConvertCharImpl(unsigned char v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ size_t fill = 0;
+ if (conv.width() >= 0) fill = conv.width();
+ ReducePadding(1, &fill);
+ if (!conv.flags().left) sink->Append(fill, ' ');
+ sink->Append(1, v);
+ if (conv.flags().left) sink->Append(fill, ' ');
+ return true;
+}
+
+bool ConvertIntImplInner(const ConvertedIntInfo &info,
+ const ConversionSpec &conv, FormatSinkImpl *sink) {
+ // Print as a sequence of Substrings:
+ // [left_spaces][sign][base_indicator][zeroes][formatted][right_spaces]
+ size_t fill = 0;
+ if (conv.width() >= 0) fill = conv.width();
+
+ string_view formatted = info.digits();
+ ReducePadding(formatted, &fill);
+
+ string_view sign = SignColumn(info.is_neg(), conv);
+ ReducePadding(sign, &fill);
+
+ string_view base_indicator = BaseIndicator(info, conv);
+ ReducePadding(base_indicator, &fill);
+
+ int precision = conv.precision();
+ bool precision_specified = precision >= 0;
+ if (!precision_specified)
+ precision = 1;
+
+ if (conv.flags().alt && conv.conv().id() == ConversionChar::o) {
+ // From POSIX description of the '#' (alt) flag:
+ // "For o conversion, it increases the precision (if necessary) to
+ // force the first digit of the result to be zero."
+ if (formatted.empty() || *formatted.begin() != '0') {
+ int needed = static_cast<int>(formatted.size()) + 1;
+ precision = std::max(precision, needed);
+ }
+ }
+
+ size_t num_zeroes = Excess(formatted.size(), precision);
+ ReducePadding(num_zeroes, &fill);
+
+ size_t num_left_spaces = !conv.flags().left ? fill : 0;
+ size_t num_right_spaces = conv.flags().left ? fill : 0;
+
+ // From POSIX description of the '0' (zero) flag:
+ // "For d, i, o, u, x, and X conversion specifiers, if a precision
+ // is specified, the '0' flag is ignored."
+ if (!precision_specified && conv.flags().zero) {
+ num_zeroes += num_left_spaces;
+ num_left_spaces = 0;
+ }
+
+ sink->Append(num_left_spaces, ' ');
+ sink->Append(sign);
+ sink->Append(base_indicator);
+ sink->Append(num_zeroes, '0');
+ sink->Append(formatted);
+ sink->Append(num_right_spaces, ' ');
+ return true;
+}
+
+template <typename T>
+bool ConvertIntImplInner(T v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ ConvertedIntInfo info(v, conv.conv());
+ if (conv.flags().basic && conv.conv().id() != ConversionChar::p) {
+ if (info.is_neg()) sink->Append(1, '-');
+ if (info.digits().empty()) {
+ sink->Append(1, '0');
+ } else {
+ sink->Append(info.digits());
+ }
+ return true;
+ }
+ return ConvertIntImplInner(info, conv, sink);
+}
+
+template <typename T>
+bool ConvertIntArg(T v, const ConversionSpec &conv, FormatSinkImpl *sink) {
+ if (conv.conv().is_float()) {
+ return FormatConvertImpl(static_cast<double>(v), conv, sink).value;
+ }
+ if (conv.conv().id() == ConversionChar::c)
+ return ConvertCharImpl(static_cast<unsigned char>(v), conv, sink);
+ if (!conv.conv().is_integral())
+ return false;
+ if (!conv.conv().is_signed() && IsSigned<T>::value) {
+ using U = typename MakeUnsigned<T>::type;
+ return FormatConvertImpl(static_cast<U>(v), conv, sink).value;
+ }
+ return ConvertIntImplInner(v, conv, sink);
+}
+
+template <typename T>
+bool ConvertFloatArg(T v, const ConversionSpec &conv, FormatSinkImpl *sink) {
+ return conv.conv().is_float() && ConvertFloatImpl(v, conv, sink);
+}
+
+inline bool ConvertStringArg(string_view v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ if (conv.conv().id() != ConversionChar::s)
+ return false;
+ if (conv.flags().basic) {
+ sink->Append(v);
+ return true;
+ }
+ return sink->PutPaddedString(v, conv.width(), conv.precision(),
+ conv.flags().left);
+}
+
+} // namespace
+
+// ==================== Strings ====================
+ConvertResult<Conv::s> FormatConvertImpl(const std::string &v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertStringArg(v, conv, sink)};
+}
+
+ConvertResult<Conv::s> FormatConvertImpl(string_view v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertStringArg(v, conv, sink)};
+}
+
+ConvertResult<Conv::s | Conv::p> FormatConvertImpl(const char *v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ if (conv.conv().id() == ConversionChar::p)
+ return {FormatConvertImpl(VoidPtr(v), conv, sink).value};
+ size_t len;
+ if (v == nullptr) {
+ len = 0;
+ } else if (conv.precision() < 0) {
+ len = std::strlen(v);
+ } else {
+ // If precision is set, we look for the null terminator on the valid range.
+ len = std::find(v, v + conv.precision(), '\0') - v;
+ }
+ return {ConvertStringArg(string_view(v, len), conv, sink)};
+}
+
+// ==================== Raw pointers ====================
+ConvertResult<Conv::p> FormatConvertImpl(VoidPtr v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ if (conv.conv().id() != ConversionChar::p)
+ return {false};
+ if (!v.value) {
+ sink->Append("(nil)");
+ return {true};
+ }
+ return {ConvertIntImplInner(v.value, conv, sink)};
+}
+
+// ==================== Floats ====================
+FloatingConvertResult FormatConvertImpl(float v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertFloatArg(v, conv, sink)};
+}
+FloatingConvertResult FormatConvertImpl(double v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertFloatArg(v, conv, sink)};
+}
+FloatingConvertResult FormatConvertImpl(long double v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertFloatArg(v, conv, sink)};
+}
+
+// ==================== Chars ====================
+IntegralConvertResult FormatConvertImpl(char v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(signed char v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(unsigned char v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+
+// ==================== Ints ====================
+IntegralConvertResult FormatConvertImpl(short v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(unsigned short v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(int v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(unsigned v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(long v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(unsigned long v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(long long v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(unsigned long long v, // NOLINT
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+IntegralConvertResult FormatConvertImpl(absl::uint128 v,
+ const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return {ConvertIntArg(v, conv, sink)};
+}
+
+template struct FormatArgImpl::TypedVTable<str_format_internal::VoidPtr>;
+
+template struct FormatArgImpl::TypedVTable<bool>;
+template struct FormatArgImpl::TypedVTable<char>;
+template struct FormatArgImpl::TypedVTable<signed char>;
+template struct FormatArgImpl::TypedVTable<unsigned char>;
+template struct FormatArgImpl::TypedVTable<short>; // NOLINT
+template struct FormatArgImpl::TypedVTable<unsigned short>; // NOLINT
+template struct FormatArgImpl::TypedVTable<int>;
+template struct FormatArgImpl::TypedVTable<unsigned>;
+template struct FormatArgImpl::TypedVTable<long>; // NOLINT
+template struct FormatArgImpl::TypedVTable<unsigned long>; // NOLINT
+template struct FormatArgImpl::TypedVTable<long long>; // NOLINT
+template struct FormatArgImpl::TypedVTable<unsigned long long>; // NOLINT
+template struct FormatArgImpl::TypedVTable<absl::uint128>;
+
+template struct FormatArgImpl::TypedVTable<float>;
+template struct FormatArgImpl::TypedVTable<double>;
+template struct FormatArgImpl::TypedVTable<long double>;
+
+template struct FormatArgImpl::TypedVTable<const char *>;
+template struct FormatArgImpl::TypedVTable<std::string>;
+template struct FormatArgImpl::TypedVTable<string_view>;
+
+} // namespace str_format_internal
+
+} // namespace absl
diff --git a/absl/strings/internal/str_format/arg.h b/absl/strings/internal/str_format/arg.h
new file mode 100644
index 00000000..a9562188
--- /dev/null
+++ b/absl/strings/internal/str_format/arg.h
@@ -0,0 +1,434 @@
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_ARG_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_ARG_H_
+
+#include <string.h>
+#include <wchar.h>
+
+#include <cstdio>
+#include <iomanip>
+#include <limits>
+#include <sstream>
+#include <string>
+#include <type_traits>
+
+#include "absl/base/port.h"
+#include "absl/meta/type_traits.h"
+#include "absl/numeric/int128.h"
+#include "absl/strings/internal/str_format/extension.h"
+#include "absl/strings/string_view.h"
+
+class Cord;
+class CordReader;
+
+namespace absl {
+
+class FormatCountCapture;
+class FormatSink;
+
+namespace str_format_internal {
+
+template <typename T, typename = void>
+struct HasUserDefinedConvert : std::false_type {};
+
+template <typename T>
+struct HasUserDefinedConvert<
+ T, void_t<decltype(AbslFormatConvert(
+ std::declval<const T&>(), std::declval<const ConversionSpec&>(),
+ std::declval<FormatSink*>()))>> : std::true_type {};
+template <typename T>
+class StreamedWrapper;
+
+// If 'v' can be converted (in the printf sense) according to 'conv',
+// then convert it, appending to `sink` and return `true`.
+// Otherwise fail and return `false`.
+// Raw pointers.
+struct VoidPtr {
+ VoidPtr() = default;
+ template <typename T,
+ decltype(reinterpret_cast<uintptr_t>(std::declval<T*>())) = 0>
+ VoidPtr(T* ptr) // NOLINT
+ : value(ptr ? reinterpret_cast<uintptr_t>(ptr) : 0) {}
+ uintptr_t value;
+};
+ConvertResult<Conv::p> FormatConvertImpl(VoidPtr v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+
+// Strings.
+ConvertResult<Conv::s> FormatConvertImpl(const std::string& v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+ConvertResult<Conv::s> FormatConvertImpl(string_view v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+ConvertResult<Conv::s | Conv::p> FormatConvertImpl(const char* v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+template <class AbslCord,
+ typename std::enable_if<
+ std::is_same<AbslCord, ::Cord>::value>::type* = nullptr,
+ class AbslCordReader = ::CordReader>
+ConvertResult<Conv::s> FormatConvertImpl(const AbslCord& value,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink) {
+ if (conv.conv().id() != ConversionChar::s) return {false};
+
+ bool is_left = conv.flags().left;
+ size_t space_remaining = 0;
+
+ int width = conv.width();
+ if (width >= 0) space_remaining = width;
+
+ size_t to_write = value.size();
+
+ int precision = conv.precision();
+ if (precision >= 0)
+ to_write = std::min(to_write, static_cast<size_t>(precision));
+
+ space_remaining = Excess(to_write, space_remaining);
+
+ if (space_remaining > 0 && !is_left) sink->Append(space_remaining, ' ');
+
+ string_view piece;
+ for (AbslCordReader reader(value);
+ to_write > 0 && reader.ReadFragment(&piece); to_write -= piece.size()) {
+ if (piece.size() > to_write) piece.remove_suffix(piece.size() - to_write);
+ sink->Append(piece);
+ }
+
+ if (space_remaining > 0 && is_left) sink->Append(space_remaining, ' ');
+ return {true};
+}
+
+using IntegralConvertResult =
+ ConvertResult<Conv::c | Conv::numeric | Conv::star>;
+using FloatingConvertResult = ConvertResult<Conv::floating>;
+
+// Floats.
+FloatingConvertResult FormatConvertImpl(float v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+FloatingConvertResult FormatConvertImpl(double v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+FloatingConvertResult FormatConvertImpl(long double v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+
+// Chars.
+IntegralConvertResult FormatConvertImpl(char v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(signed char v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(unsigned char v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+
+// Ints.
+IntegralConvertResult FormatConvertImpl(short v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(unsigned short v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(int v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(unsigned v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(long v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(unsigned long v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(long long v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(unsigned long long v, // NOLINT
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+IntegralConvertResult FormatConvertImpl(uint128 v, const ConversionSpec& conv,
+ FormatSinkImpl* sink);
+template <typename T, enable_if_t<std::is_same<T, bool>::value, int> = 0>
+IntegralConvertResult FormatConvertImpl(T v, const ConversionSpec& conv,
+ FormatSinkImpl* sink) {
+ return FormatConvertImpl(static_cast<int>(v), conv, sink);
+}
+
+// We provide this function to help the checker, but it is never defined.
+// FormatArgImpl will use the underlying Convert functions instead.
+template <typename T>
+typename std::enable_if<std::is_enum<T>::value &&
+ !HasUserDefinedConvert<T>::value,
+ IntegralConvertResult>::type
+FormatConvertImpl(T v, const ConversionSpec& conv, FormatSinkImpl* sink);
+
+template <typename T>
+ConvertResult<Conv::s> FormatConvertImpl(const StreamedWrapper<T>& v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* out) {
+ std::ostringstream oss;
+ oss << v.v_;
+ if (!oss) return {false};
+ return str_format_internal::FormatConvertImpl(oss.str(), conv, out);
+}
+
+// Use templates and dependent types to delay evaluation of the function
+// until after FormatCountCapture is fully defined.
+struct FormatCountCaptureHelper {
+ template <class T = int>
+ static ConvertResult<Conv::n> ConvertHelper(const FormatCountCapture& v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink) {
+ const absl::enable_if_t<sizeof(T) != 0, FormatCountCapture>& v2 = v;
+
+ if (conv.conv().id() != str_format_internal::ConversionChar::n)
+ return {false};
+ *v2.p_ = static_cast<int>(sink->size());
+ return {true};
+ }
+};
+
+template <class T = int>
+ConvertResult<Conv::n> FormatConvertImpl(const FormatCountCapture& v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* sink) {
+ return FormatCountCaptureHelper::ConvertHelper(v, conv, sink);
+}
+
+// Helper friend struct to hide implementation details from the public API of
+// FormatArgImpl.
+struct FormatArgImplFriend {
+ template <typename Arg>
+ static bool ToInt(Arg arg, int* out) {
+ if (!arg.vtbl_->to_int) return false;
+ *out = arg.vtbl_->to_int(arg.data_);
+ return true;
+ }
+
+ template <typename Arg>
+ static bool Convert(Arg arg, const str_format_internal::ConversionSpec& conv,
+ FormatSinkImpl* out) {
+ return arg.vtbl_->convert(arg.data_, conv, out);
+ }
+
+ template <typename Arg>
+ static const void* GetVTablePtrForTest(Arg arg) {
+ return arg.vtbl_;
+ }
+};
+
+// A type-erased handle to a format argument.
+class FormatArgImpl {
+ private:
+ enum { kInlinedSpace = 8 };
+
+ using VoidPtr = str_format_internal::VoidPtr;
+
+ union Data {
+ const void* ptr;
+ const volatile void* volatile_ptr;
+ char buf[kInlinedSpace];
+ };
+
+ struct VTable {
+ bool (*convert)(Data, const str_format_internal::ConversionSpec& conv,
+ FormatSinkImpl* out);
+ int (*to_int)(Data);
+ };
+
+ template <typename T>
+ struct store_by_value
+ : std::integral_constant<bool, (sizeof(T) <= kInlinedSpace) &&
+ (std::is_integral<T>::value ||
+ std::is_floating_point<T>::value ||
+ std::is_pointer<T>::value ||
+ std::is_same<VoidPtr, T>::value)> {};
+
+ enum StoragePolicy { ByPointer, ByVolatilePointer, ByValue };
+ template <typename T>
+ struct storage_policy
+ : std::integral_constant<StoragePolicy,
+ (std::is_volatile<T>::value
+ ? ByVolatilePointer
+ : (store_by_value<T>::value ? ByValue
+ : ByPointer))> {
+ };
+
+ // An instance of an FormatArgImpl::VTable suitable for 'T'.
+ template <typename T>
+ struct TypedVTable;
+
+ // To reduce the number of vtables we will decay values before hand.
+ // Anything with a user-defined Convert will get its own vtable.
+ // For everything else:
+ // - Decay char* and char arrays into `const char*`
+ // - Decay any other pointer to `const void*`
+ // - Decay all enums to their underlying type.
+ // - Decay function pointers to void*.
+ template <typename T, typename = void>
+ struct DecayType {
+ static constexpr bool kHasUserDefined =
+ str_format_internal::HasUserDefinedConvert<T>::value;
+ using type = typename std::conditional<
+ !kHasUserDefined && std::is_convertible<T, const char*>::value,
+ const char*,
+ typename std::conditional<!kHasUserDefined &&
+ std::is_convertible<T, VoidPtr>::value,
+ VoidPtr, const T&>::type>::type;
+ };
+ template <typename T>
+ struct DecayType<T,
+ typename std::enable_if<
+ !str_format_internal::HasUserDefinedConvert<T>::value &&
+ std::is_enum<T>::value>::type> {
+ using type = typename std::underlying_type<T>::type;
+ };
+
+ public:
+ template <typename T>
+ explicit FormatArgImpl(const T& value) {
+ using D = typename DecayType<T>::type;
+ static_assert(
+ std::is_same<D, const T&>::value || storage_policy<D>::value == ByValue,
+ "Decayed types must be stored by value");
+ Init(static_cast<D>(value));
+ }
+
+ private:
+ friend struct str_format_internal::FormatArgImplFriend;
+ template <typename T, StoragePolicy = storage_policy<T>::value>
+ struct Manager;
+
+ template <typename T>
+ struct Manager<T, ByPointer> {
+ static Data SetValue(const T& value) {
+ Data data;
+ data.ptr = &value;
+ return data;
+ }
+
+ static const T& Value(Data arg) { return *static_cast<const T*>(arg.ptr); }
+ };
+
+ template <typename T>
+ struct Manager<T, ByVolatilePointer> {
+ static Data SetValue(const T& value) {
+ Data data;
+ data.volatile_ptr = &value;
+ return data;
+ }
+
+ static const T& Value(Data arg) {
+ return *static_cast<const T*>(arg.volatile_ptr);
+ }
+ };
+
+ template <typename T>
+ struct Manager<T, ByValue> {
+ static Data SetValue(const T& value) {
+ Data data;
+ memcpy(data.buf, &value, sizeof(value));
+ return data;
+ }
+
+ static T Value(Data arg) {
+ T value;
+ memcpy(&value, arg.buf, sizeof(T));
+ return value;
+ }
+ };
+
+ template <typename T>
+ void Init(const T& value);
+
+ template <typename T>
+ static int ToIntVal(const T& val) {
+ using CommonType = typename std::conditional<std::is_signed<T>::value,
+ int64_t, uint64_t>::type;
+ if (static_cast<CommonType>(val) >
+ static_cast<CommonType>(std::numeric_limits<int>::max())) {
+ return std::numeric_limits<int>::max();
+ } else if (std::is_signed<T>::value &&
+ static_cast<CommonType>(val) <
+ static_cast<CommonType>(std::numeric_limits<int>::min())) {
+ return std::numeric_limits<int>::min();
+ }
+ return static_cast<int>(val);
+ }
+
+ Data data_;
+ const VTable* vtbl_;
+};
+
+template <typename T>
+struct FormatArgImpl::TypedVTable {
+ private:
+ static bool ConvertImpl(Data arg,
+ const str_format_internal::ConversionSpec& conv,
+ FormatSinkImpl* out) {
+ return str_format_internal::FormatConvertImpl(Manager<T>::Value(arg), conv,
+ out)
+ .value;
+ }
+
+ template <typename U = T, typename = void>
+ struct ToIntImpl {
+ static constexpr int (*value)(Data) = nullptr;
+ };
+
+ template <typename U>
+ struct ToIntImpl<U,
+ typename std::enable_if<std::is_integral<U>::value>::type> {
+ static int Invoke(Data arg) { return ToIntVal(Manager<T>::Value(arg)); }
+ static constexpr int (*value)(Data) = &Invoke;
+ };
+
+ template <typename U>
+ struct ToIntImpl<U, typename std::enable_if<std::is_enum<U>::value>::type> {
+ static int Invoke(Data arg) {
+ return ToIntVal(static_cast<typename std::underlying_type<T>::type>(
+ Manager<T>::Value(arg)));
+ }
+ static constexpr int (*value)(Data) = &Invoke;
+ };
+
+ public:
+ static constexpr VTable value{&ConvertImpl, ToIntImpl<>::value};
+};
+
+template <typename T>
+constexpr FormatArgImpl::VTable FormatArgImpl::TypedVTable<T>::value;
+
+template <typename T>
+void FormatArgImpl::Init(const T& value) {
+ data_ = Manager<T>::SetValue(value);
+ vtbl_ = &TypedVTable<T>::value;
+}
+
+extern template struct FormatArgImpl::TypedVTable<str_format_internal::VoidPtr>;
+
+extern template struct FormatArgImpl::TypedVTable<bool>;
+extern template struct FormatArgImpl::TypedVTable<char>;
+extern template struct FormatArgImpl::TypedVTable<signed char>;
+extern template struct FormatArgImpl::TypedVTable<unsigned char>;
+extern template struct FormatArgImpl::TypedVTable<short>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<unsigned short>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<int>;
+extern template struct FormatArgImpl::TypedVTable<unsigned>;
+extern template struct FormatArgImpl::TypedVTable<long>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<unsigned long>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<long long>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<
+ unsigned long long>; // NOLINT
+extern template struct FormatArgImpl::TypedVTable<uint128>;
+
+extern template struct FormatArgImpl::TypedVTable<float>;
+extern template struct FormatArgImpl::TypedVTable<double>;
+extern template struct FormatArgImpl::TypedVTable<long double>;
+
+extern template struct FormatArgImpl::TypedVTable<const char*>;
+extern template struct FormatArgImpl::TypedVTable<std::string>;
+extern template struct FormatArgImpl::TypedVTable<string_view>;
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_ARG_H_
diff --git a/absl/strings/internal/str_format/arg_test.cc b/absl/strings/internal/str_format/arg_test.cc
new file mode 100644
index 00000000..83d59048
--- /dev/null
+++ b/absl/strings/internal/str_format/arg_test.cc
@@ -0,0 +1,111 @@
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+#include "absl/strings/internal/str_format/arg.h"
+
+#include <ostream>
+#include <string>
+#include "gtest/gtest.h"
+#include "absl/strings/str_format.h"
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+class FormatArgImplTest : public ::testing::Test {
+ public:
+ enum Color { kRed, kGreen, kBlue };
+
+ static const char *hi() { return "hi"; }
+};
+
+TEST_F(FormatArgImplTest, ToInt) {
+ int out = 0;
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(FormatArgImpl(1), &out));
+ EXPECT_EQ(1, out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(FormatArgImpl(-1), &out));
+ EXPECT_EQ(-1, out);
+ EXPECT_TRUE(
+ FormatArgImplFriend::ToInt(FormatArgImpl(static_cast<char>(64)), &out));
+ EXPECT_EQ(64, out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(
+ FormatArgImpl(static_cast<unsigned long long>(123456)), &out)); // NOLINT
+ EXPECT_EQ(123456, out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(
+ FormatArgImpl(static_cast<unsigned long long>( // NOLINT
+ std::numeric_limits<int>::max()) +
+ 1),
+ &out));
+ EXPECT_EQ(std::numeric_limits<int>::max(), out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(
+ FormatArgImpl(static_cast<long long>( // NOLINT
+ std::numeric_limits<int>::min()) -
+ 10),
+ &out));
+ EXPECT_EQ(std::numeric_limits<int>::min(), out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(FormatArgImpl(false), &out));
+ EXPECT_EQ(0, out);
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(FormatArgImpl(true), &out));
+ EXPECT_EQ(1, out);
+ EXPECT_FALSE(FormatArgImplFriend::ToInt(FormatArgImpl(2.2), &out));
+ EXPECT_FALSE(FormatArgImplFriend::ToInt(FormatArgImpl(3.2f), &out));
+ EXPECT_FALSE(FormatArgImplFriend::ToInt(
+ FormatArgImpl(static_cast<int *>(nullptr)), &out));
+ EXPECT_FALSE(FormatArgImplFriend::ToInt(FormatArgImpl(hi()), &out));
+ EXPECT_FALSE(FormatArgImplFriend::ToInt(FormatArgImpl("hi"), &out));
+ EXPECT_TRUE(FormatArgImplFriend::ToInt(FormatArgImpl(kBlue), &out));
+ EXPECT_EQ(2, out);
+}
+
+extern const char kMyArray[];
+
+TEST_F(FormatArgImplTest, CharArraysDecayToCharPtr) {
+ const char* a = "";
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(a)),
+ FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl("")));
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(a)),
+ FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl("A")));
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(a)),
+ FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl("ABC")));
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(a)),
+ FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(kMyArray)));
+}
+
+TEST_F(FormatArgImplTest, OtherPtrDecayToVoidPtr) {
+ auto expected = FormatArgImplFriend::GetVTablePtrForTest(
+ FormatArgImpl(static_cast<void *>(nullptr)));
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(
+ FormatArgImpl(static_cast<int *>(nullptr))),
+ expected);
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(
+ FormatArgImpl(static_cast<volatile int *>(nullptr))),
+ expected);
+
+ auto p = static_cast<void (*)()>([] {});
+ EXPECT_EQ(FormatArgImplFriend::GetVTablePtrForTest(FormatArgImpl(p)),
+ expected);
+}
+
+TEST_F(FormatArgImplTest, WorksWithCharArraysOfUnknownSize) {
+ std::string s;
+ FormatSinkImpl sink(&s);
+ ConversionSpec conv;
+ conv.set_conv(ConversionChar::FromChar('s'));
+ conv.set_flags(Flags());
+ conv.set_width(-1);
+ conv.set_precision(-1);
+ EXPECT_TRUE(
+ FormatArgImplFriend::Convert(FormatArgImpl(kMyArray), conv, &sink));
+ sink.Flush();
+ EXPECT_EQ("ABCDE", s);
+}
+const char kMyArray[] = "ABCDE";
+
+} // namespace
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/bind.cc b/absl/strings/internal/str_format/bind.cc
new file mode 100644
index 00000000..33e86415
--- /dev/null
+++ b/absl/strings/internal/str_format/bind.cc
@@ -0,0 +1,232 @@
+#include "absl/strings/internal/str_format/bind.h"
+
+#include <cerrno>
+#include <limits>
+#include <sstream>
+#include <string>
+
+namespace absl {
+namespace str_format_internal {
+
+namespace {
+
+inline bool BindFromPosition(int position, int* value,
+ absl::Span<const FormatArgImpl> pack) {
+ assert(position > 0);
+ if (static_cast<size_t>(position) > pack.size()) {
+ return false;
+ }
+ // -1 because positions are 1-based
+ return FormatArgImplFriend::ToInt(pack[position - 1], value);
+}
+
+class ArgContext {
+ public:
+ explicit ArgContext(absl::Span<const FormatArgImpl> pack) : pack_(pack) {}
+
+ // Fill 'bound' with the results of applying the context's argument pack
+ // to the specified 'props'. We synthesize a BoundConversion by
+ // lining up a UnboundConversion with a user argument. We also
+ // resolve any '*' specifiers for width and precision, so after
+ // this call, 'bound' has all the information it needs to be formatted.
+ // Returns false on failure.
+ bool Bind(const UnboundConversion *props, BoundConversion *bound);
+
+ private:
+ absl::Span<const FormatArgImpl> pack_;
+};
+
+inline bool ArgContext::Bind(const UnboundConversion* unbound,
+ BoundConversion* bound) {
+ const FormatArgImpl* arg = nullptr;
+ int arg_position = unbound->arg_position;
+ if (static_cast<size_t>(arg_position - 1) >= pack_.size()) return false;
+ arg = &pack_[arg_position - 1]; // 1-based
+
+ if (!unbound->flags.basic) {
+ int width = unbound->width.value();
+ bool force_left = false;
+ if (unbound->width.is_from_arg()) {
+ if (!BindFromPosition(unbound->width.get_from_arg(), &width, pack_))
+ return false;
+ if (width < 0) {
+ // "A negative field width is taken as a '-' flag followed by a
+ // positive field width."
+ force_left = true;
+ width = -width;
+ }
+ }
+
+ int precision = unbound->precision.value();
+ if (unbound->precision.is_from_arg()) {
+ if (!BindFromPosition(unbound->precision.get_from_arg(), &precision,
+ pack_))
+ return false;
+ }
+
+ bound->set_width(width);
+ bound->set_precision(precision);
+ bound->set_flags(unbound->flags);
+ if (force_left)
+ bound->set_left(true);
+ } else {
+ bound->set_flags(unbound->flags);
+ bound->set_width(-1);
+ bound->set_precision(-1);
+ }
+
+ bound->set_length_mod(unbound->length_mod);
+ bound->set_conv(unbound->conv);
+ bound->set_arg(arg);
+ return true;
+}
+
+template <typename Converter>
+class ConverterConsumer {
+ public:
+ ConverterConsumer(Converter converter, absl::Span<const FormatArgImpl> pack)
+ : converter_(converter), arg_context_(pack) {}
+
+ bool Append(string_view s) {
+ converter_.Append(s);
+ return true;
+ }
+ bool ConvertOne(const UnboundConversion& conv, string_view conv_string) {
+ BoundConversion bound;
+ if (!arg_context_.Bind(&conv, &bound)) return false;
+ return converter_.ConvertOne(bound, conv_string);
+ }
+
+ private:
+ Converter converter_;
+ ArgContext arg_context_;
+};
+
+template <typename Converter>
+bool ConvertAll(const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args,
+ const Converter& converter) {
+ const ParsedFormatBase* pc = format.parsed_conversion();
+ if (pc)
+ return pc->ProcessFormat(ConverterConsumer<Converter>(converter, args));
+
+ return ParseFormatString(format.str(),
+ ConverterConsumer<Converter>(converter, args));
+}
+
+class DefaultConverter {
+ public:
+ explicit DefaultConverter(FormatSinkImpl* sink) : sink_(sink) {}
+
+ void Append(string_view s) const { sink_->Append(s); }
+
+ bool ConvertOne(const BoundConversion& bound, string_view /*conv*/) const {
+ return FormatArgImplFriend::Convert(*bound.arg(), bound, sink_);
+ }
+
+ private:
+ FormatSinkImpl* sink_;
+};
+
+class SummarizingConverter {
+ public:
+ explicit SummarizingConverter(FormatSinkImpl* sink) : sink_(sink) {}
+
+ void Append(string_view s) const { sink_->Append(s); }
+
+ bool ConvertOne(const BoundConversion& bound, string_view /*conv*/) const {
+ UntypedFormatSpecImpl spec("%d");
+
+ std::ostringstream ss;
+ ss << "{" << Streamable(spec, {*bound.arg()}) << ":" << bound.flags();
+ if (bound.width() >= 0) ss << bound.width();
+ if (bound.precision() >= 0) ss << "." << bound.precision();
+ ss << bound.length_mod() << bound.conv() << "}";
+ Append(ss.str());
+ return true;
+ }
+
+ private:
+ FormatSinkImpl* sink_;
+};
+
+} // namespace
+
+bool BindWithPack(const UnboundConversion* props,
+ absl::Span<const FormatArgImpl> pack,
+ BoundConversion* bound) {
+ return ArgContext(pack).Bind(props, bound);
+}
+
+std::string Summarize(const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ typedef SummarizingConverter Converter;
+ std::string out;
+ {
+ // inner block to destroy sink before returning out. It ensures a last
+ // flush.
+ FormatSinkImpl sink(&out);
+ if (!ConvertAll(format, args, Converter(&sink))) {
+ sink.Flush();
+ out.clear();
+ }
+ }
+ return out;
+}
+
+bool FormatUntyped(FormatRawSinkImpl raw_sink,
+ const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ FormatSinkImpl sink(raw_sink);
+ using Converter = DefaultConverter;
+ if (!ConvertAll(format, args, Converter(&sink))) {
+ sink.Flush();
+ return false;
+ }
+ return true;
+}
+
+std::ostream& Streamable::Print(std::ostream& os) const {
+ if (!FormatUntyped(&os, format_, args_)) os.setstate(std::ios::failbit);
+ return os;
+}
+
+std::string& AppendPack(std::string* out, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ size_t orig = out->size();
+ if (!FormatUntyped(out, format, args)) out->resize(orig);
+ return *out;
+}
+
+int FprintF(std::FILE* output, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ FILERawSink sink(output);
+ if (!FormatUntyped(&sink, format, args)) {
+ errno = EINVAL;
+ return -1;
+ }
+ if (sink.error()) {
+ errno = sink.error();
+ return -1;
+ }
+ if (sink.count() > std::numeric_limits<int>::max()) {
+ errno = EFBIG;
+ return -1;
+ }
+ return static_cast<int>(sink.count());
+}
+
+int SnprintF(char* output, size_t size, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ BufferRawSink sink(output, size ? size - 1 : 0);
+ if (!FormatUntyped(&sink, format, args)) {
+ errno = EINVAL;
+ return -1;
+ }
+ size_t total = sink.total_written();
+ if (size) output[std::min(total, size - 1)] = 0;
+ return static_cast<int>(total);
+}
+
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/bind.h b/absl/strings/internal/str_format/bind.h
new file mode 100644
index 00000000..40086112
--- /dev/null
+++ b/absl/strings/internal/str_format/bind.h
@@ -0,0 +1,189 @@
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
+
+#include <array>
+#include <cstdio>
+#include <sstream>
+#include <string>
+
+#include "absl/base/port.h"
+#include "absl/container/inlined_vector.h"
+#include "absl/strings/internal/str_format/arg.h"
+#include "absl/strings/internal/str_format/checker.h"
+#include "absl/strings/internal/str_format/parser.h"
+#include "absl/types/span.h"
+
+namespace absl {
+
+class UntypedFormatSpec;
+
+namespace str_format_internal {
+
+class BoundConversion : public ConversionSpec {
+ public:
+ const FormatArgImpl* arg() const { return arg_; }
+ void set_arg(const FormatArgImpl* a) { arg_ = a; }
+
+ private:
+ const FormatArgImpl* arg_;
+};
+
+// This is the type-erased class that the implementation uses.
+class UntypedFormatSpecImpl {
+ public:
+ UntypedFormatSpecImpl() = delete;
+
+ explicit UntypedFormatSpecImpl(string_view s) : str_(s), pc_() {}
+ explicit UntypedFormatSpecImpl(
+ const str_format_internal::ParsedFormatBase* pc)
+ : pc_(pc) {}
+ string_view str() const { return str_; }
+ const str_format_internal::ParsedFormatBase* parsed_conversion() const {
+ return pc_;
+ }
+
+ template <typename T>
+ static const UntypedFormatSpecImpl& Extract(const T& s) {
+ return s.spec_;
+ }
+
+ private:
+ string_view str_;
+ const str_format_internal::ParsedFormatBase* pc_;
+};
+
+template <typename T, typename...>
+struct MakeDependent {
+ using type = T;
+};
+
+// Implicitly convertible from `const char*`, `string_view`, and the
+// `ExtendedParsedFormat` type. This abstraction allows all format functions to
+// operate on any without providing too many overloads.
+template <typename... Args>
+class FormatSpecTemplate
+ : public MakeDependent<UntypedFormatSpec, Args...>::type {
+ using Base = typename MakeDependent<UntypedFormatSpec, Args...>::type;
+
+ public:
+#if ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+ // Honeypot overload for when the std::string is not constexpr.
+ // We use the 'unavailable' attribute to give a better compiler error than
+ // just 'method is deleted'.
+ FormatSpecTemplate(...) // NOLINT
+ __attribute__((unavailable("Format std::string is not constexpr.")));
+
+ // Honeypot overload for when the format is constexpr and invalid.
+ // We use the 'unavailable' attribute to give a better compiler error than
+ // just 'method is deleted'.
+ // To avoid checking the format twice, we just check that the format is
+ // constexpr. If is it valid, then the overload below will kick in.
+ // We add the template here to make this overload have lower priority.
+ template <typename = void>
+ FormatSpecTemplate(const char* s) // NOLINT
+ __attribute__((
+ enable_if(str_format_internal::EnsureConstexpr(s), "constexpr trap"),
+ unavailable(
+ "Format specified does not match the arguments passed.")));
+
+ template <typename T = void>
+ FormatSpecTemplate(string_view s) // NOLINT
+ __attribute__((enable_if(str_format_internal::EnsureConstexpr(s),
+ "constexpr trap"))) {
+ static_assert(sizeof(T*) == 0,
+ "Format specified does not match the arguments passed.");
+ }
+
+ // Good format overload.
+ FormatSpecTemplate(const char* s) // NOLINT
+ __attribute__((enable_if(ValidFormatImpl<ArgumentToConv<Args>()...>(s),
+ "bad format trap")))
+ : Base(s) {}
+
+ FormatSpecTemplate(string_view s) // NOLINT
+ __attribute__((enable_if(ValidFormatImpl<ArgumentToConv<Args>()...>(s),
+ "bad format trap")))
+ : Base(s) {}
+
+#else // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+ FormatSpecTemplate(const char* s) : Base(s) {} // NOLINT
+ FormatSpecTemplate(string_view s) : Base(s) {} // NOLINT
+
+#endif // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+ template <Conv... C, typename = typename std::enable_if<
+ sizeof...(C) == sizeof...(Args) &&
+ AllOf(Contains(ArgumentToConv<Args>(),
+ C)...)>::type>
+ FormatSpecTemplate(const ExtendedParsedFormat<C...>& pc) // NOLINT
+ : Base(&pc) {}
+};
+
+template <typename... Args>
+struct FormatSpecDeductionBarrier {
+ using type = FormatSpecTemplate<Args...>;
+};
+
+class Streamable {
+ public:
+ Streamable(const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args)
+ : format_(format), args_(args.begin(), args.end()) {}
+
+ std::ostream& Print(std::ostream& os) const;
+
+ friend std::ostream& operator<<(std::ostream& os, const Streamable& l) {
+ return l.Print(os);
+ }
+
+ private:
+ const UntypedFormatSpecImpl& format_;
+ absl::InlinedVector<FormatArgImpl, 4> args_;
+};
+
+// for testing
+std::string Summarize(const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args);
+bool BindWithPack(const UnboundConversion* props,
+ absl::Span<const FormatArgImpl> pack, BoundConversion* bound);
+
+bool FormatUntyped(FormatRawSinkImpl raw_sink,
+ const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args);
+
+std::string& AppendPack(std::string* out, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args);
+
+inline std::string FormatPack(const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args) {
+ std::string out;
+ AppendPack(&out, format, args);
+ return out;
+}
+
+int FprintF(std::FILE* output, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args);
+int SnprintF(char* output, size_t size, const UntypedFormatSpecImpl& format,
+ absl::Span<const FormatArgImpl> args);
+
+// Returned by Streamed(v). Converts via '%s' to the std::string created
+// by std::ostream << v.
+template <typename T>
+class StreamedWrapper {
+ public:
+ explicit StreamedWrapper(const T& v) : v_(v) { }
+
+ private:
+ template <typename S>
+ friend ConvertResult<Conv::s> FormatConvertImpl(const StreamedWrapper<S>& v,
+ const ConversionSpec& conv,
+ FormatSinkImpl* out);
+ const T& v_;
+};
+
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_BIND_H_
diff --git a/absl/strings/internal/str_format/bind_test.cc b/absl/strings/internal/str_format/bind_test.cc
new file mode 100644
index 00000000..47575739
--- /dev/null
+++ b/absl/strings/internal/str_format/bind_test.cc
@@ -0,0 +1,131 @@
+#include "absl/strings/internal/str_format/bind.h"
+
+#include <string.h>
+
+#include "gtest/gtest.h"
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+template <typename T, size_t N>
+size_t ArraySize(T (&)[N]) {
+ return N;
+}
+
+class FormatBindTest : public ::testing::Test {
+ public:
+ bool Extract(const char *s, UnboundConversion *props, int *next) const {
+ absl::string_view src = s;
+ return ConsumeUnboundConversion(&src, props, next) && src.empty();
+ }
+};
+
+TEST_F(FormatBindTest, BindSingle) {
+ struct Expectation {
+ int line;
+ const char *fmt;
+ int ok_phases;
+ const FormatArgImpl *arg;
+ int width;
+ int precision;
+ int next_arg;
+ };
+ const int no = -1;
+ const int ia[] = { 10, 20, 30, 40};
+ const FormatArgImpl args[] = {FormatArgImpl(ia[0]), FormatArgImpl(ia[1]),
+ FormatArgImpl(ia[2]), FormatArgImpl(ia[3])};
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wmissing-field-initializers"
+ const Expectation kExpect[] = {
+ {__LINE__, "d", 2, &args[0], no, no, 2},
+ {__LINE__, "4d", 2, &args[0], 4, no, 2},
+ {__LINE__, ".5d", 2, &args[0], no, 5, 2},
+ {__LINE__, "4.5d", 2, &args[0], 4, 5, 2},
+ {__LINE__, "*d", 2, &args[1], 10, no, 3},
+ {__LINE__, ".*d", 2, &args[1], no, 10, 3},
+ {__LINE__, "*.*d", 2, &args[2], 10, 20, 4},
+ {__LINE__, "1$d", 2, &args[0], no, no, 0},
+ {__LINE__, "2$d", 2, &args[1], no, no, 0},
+ {__LINE__, "3$d", 2, &args[2], no, no, 0},
+ {__LINE__, "4$d", 2, &args[3], no, no, 0},
+ {__LINE__, "2$*1$d", 2, &args[1], 10, no, 0},
+ {__LINE__, "2$*2$d", 2, &args[1], 20, no, 0},
+ {__LINE__, "2$*3$d", 2, &args[1], 30, no, 0},
+ {__LINE__, "2$.*1$d", 2, &args[1], no, 10, 0},
+ {__LINE__, "2$.*2$d", 2, &args[1], no, 20, 0},
+ {__LINE__, "2$.*3$d", 2, &args[1], no, 30, 0},
+ {__LINE__, "2$*3$.*1$d", 2, &args[1], 30, 10, 0},
+ {__LINE__, "2$*2$.*2$d", 2, &args[1], 20, 20, 0},
+ {__LINE__, "2$*1$.*3$d", 2, &args[1], 10, 30, 0},
+ {__LINE__, "2$*3$.*1$d", 2, &args[1], 30, 10, 0},
+ {__LINE__, "1$*d", 0}, // indexed, then positional
+ {__LINE__, "*2$d", 0}, // positional, then indexed
+ {__LINE__, "6$d", 1}, // arg position out of bounds
+ {__LINE__, "1$6$d", 0}, // width position incorrectly specified
+ {__LINE__, "1$.6$d", 0}, // precision position incorrectly specified
+ {__LINE__, "1$*6$d", 1}, // width position out of bounds
+ {__LINE__, "1$.*6$d", 1}, // precision position out of bounds
+ };
+#pragma GCC diagnostic pop
+ for (const Expectation &e : kExpect) {
+ SCOPED_TRACE(e.line);
+ SCOPED_TRACE(e.fmt);
+ UnboundConversion props;
+ BoundConversion bound;
+ int ok_phases = 0;
+ int next = 0;
+ if (Extract(e.fmt, &props, &next)) {
+ ++ok_phases;
+ if (BindWithPack(&props, args, &bound)) {
+ ++ok_phases;
+ }
+ }
+ EXPECT_EQ(e.ok_phases, ok_phases);
+ if (e.ok_phases < 2) continue;
+ if (e.arg != nullptr) {
+ EXPECT_EQ(e.arg, bound.arg());
+ }
+ EXPECT_EQ(e.width, bound.width());
+ EXPECT_EQ(e.precision, bound.precision());
+ }
+}
+
+TEST_F(FormatBindTest, FormatPack) {
+ struct Expectation {
+ int line;
+ const char *fmt;
+ const char *summary;
+ };
+ const int ia[] = { 10, 20, 30, 40, -10 };
+ const FormatArgImpl args[] = {FormatArgImpl(ia[0]), FormatArgImpl(ia[1]),
+ FormatArgImpl(ia[2]), FormatArgImpl(ia[3]),
+ FormatArgImpl(ia[4])};
+ const Expectation kExpect[] = {
+ {__LINE__, "a%4db%dc", "a{10:4d}b{20:d}c"},
+ {__LINE__, "a%.4db%dc", "a{10:.4d}b{20:d}c"},
+ {__LINE__, "a%4.5db%dc", "a{10:4.5d}b{20:d}c"},
+ {__LINE__, "a%db%4.5dc", "a{10:d}b{20:4.5d}c"},
+ {__LINE__, "a%db%*.*dc", "a{10:d}b{40:20.30d}c"},
+ {__LINE__, "a%.*fb", "a{20:.10f}b"},
+ {__LINE__, "a%1$db%2$*3$.*4$dc", "a{10:d}b{20:30.40d}c"},
+ {__LINE__, "a%4$db%3$*2$.*1$dc", "a{40:d}b{30:20.10d}c"},
+ {__LINE__, "a%04ldb", "a{10:04ld}b"},
+ {__LINE__, "a%-#04lldb", "a{10:-#04lld}b"},
+ {__LINE__, "a%1$*5$db", "a{10:-10d}b"},
+ {__LINE__, "a%1$.*5$db", "a{10:d}b"},
+ };
+ for (const Expectation &e : kExpect) {
+ absl::string_view fmt = e.fmt;
+ SCOPED_TRACE(e.line);
+ SCOPED_TRACE(e.fmt);
+ UntypedFormatSpecImpl format(fmt);
+ EXPECT_EQ(e.summary,
+ str_format_internal::Summarize(format, absl::MakeSpan(args)))
+ << "line:" << e.line;
+ }
+}
+
+} // namespace
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/checker.h b/absl/strings/internal/str_format/checker.h
new file mode 100644
index 00000000..8b594f2d
--- /dev/null
+++ b/absl/strings/internal/str_format/checker.h
@@ -0,0 +1,325 @@
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_CHECKER_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_CHECKER_H_
+
+#include "absl/strings/internal/str_format/arg.h"
+#include "absl/strings/internal/str_format/extension.h"
+
+// Compile time check support for entry points.
+
+#ifndef ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+#if defined(__clang__) && !defined(__native_client__)
+#if __has_attribute(enable_if)
+#define ABSL_INTERNAL_ENABLE_FORMAT_CHECKER 1
+#endif // __has_attribute(enable_if)
+#endif // defined(__clang__) && !defined(__native_client__)
+#endif // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+namespace absl {
+namespace str_format_internal {
+
+constexpr bool AllOf() { return true; }
+
+template <typename... T>
+constexpr bool AllOf(bool b, T... t) {
+ return b && AllOf(t...);
+}
+
+template <typename Arg>
+constexpr Conv ArgumentToConv() {
+ return decltype(str_format_internal::FormatConvertImpl(
+ std::declval<const Arg&>(), std::declval<const ConversionSpec&>(),
+ std::declval<FormatSinkImpl*>()))::kConv;
+}
+
+#if ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+constexpr bool ContainsChar(const char* chars, char c) {
+ return *chars == c || (*chars && ContainsChar(chars + 1, c));
+}
+
+// A constexpr compatible list of Convs.
+struct ConvList {
+ const Conv* array;
+ int count;
+
+ // We do the bound check here to avoid having to do it on the callers.
+ // Returning an empty Conv has the same effect as short circuiting because it
+ // will never match any conversion.
+ constexpr Conv operator[](int i) const {
+ return i < count ? array[i] : Conv{};
+ }
+
+ constexpr ConvList without_front() const {
+ return count != 0 ? ConvList{array + 1, count - 1} : *this;
+ }
+};
+
+template <size_t count>
+struct ConvListT {
+ // Make sure the array has size > 0.
+ Conv list[count ? count : 1];
+};
+
+constexpr char GetChar(string_view str, size_t index) {
+ return index < str.size() ? str[index] : char{};
+}
+
+constexpr string_view ConsumeFront(string_view str, size_t len = 1) {
+ return len <= str.size() ? string_view(str.data() + len, str.size() - len)
+ : string_view();
+}
+
+constexpr string_view ConsumeAnyOf(string_view format, const char* chars) {
+ return ContainsChar(chars, GetChar(format, 0))
+ ? ConsumeAnyOf(ConsumeFront(format), chars)
+ : format;
+}
+
+constexpr bool IsDigit(char c) { return c >= '0' && c <= '9'; }
+
+// Helper class for the ParseDigits function.
+// It encapsulates the two return values we need there.
+struct Integer {
+ string_view format;
+ int value;
+
+ // If the next character is a '$', consume it.
+ // Otherwise, make `this` an invalid positional argument.
+ constexpr Integer ConsumePositionalDollar() const {
+ return GetChar(format, 0) == '$' ? Integer{ConsumeFront(format), value}
+ : Integer{format, 0};
+ }
+};
+
+constexpr Integer ParseDigits(string_view format, int value = 0) {
+ return IsDigit(GetChar(format, 0))
+ ? ParseDigits(ConsumeFront(format),
+ 10 * value + GetChar(format, 0) - '0')
+ : Integer{format, value};
+}
+
+// Parse digits for a positional argument.
+// The parsing also consumes the '$'.
+constexpr Integer ParsePositional(string_view format) {
+ return ParseDigits(format).ConsumePositionalDollar();
+}
+
+// Parses a single conversion specifier.
+// See ConvParser::Run() for post conditions.
+class ConvParser {
+ constexpr ConvParser SetFormat(string_view format) const {
+ return ConvParser(format, args_, error_, arg_position_, is_positional_);
+ }
+
+ constexpr ConvParser SetArgs(ConvList args) const {
+ return ConvParser(format_, args, error_, arg_position_, is_positional_);
+ }
+
+ constexpr ConvParser SetError(bool error) const {
+ return ConvParser(format_, args_, error_ || error, arg_position_,
+ is_positional_);
+ }
+
+ constexpr ConvParser SetArgPosition(int arg_position) const {
+ return ConvParser(format_, args_, error_, arg_position, is_positional_);
+ }
+
+ // Consumes the next arg and verifies that it matches `conv`.
+ // `error_` is set if there is no next arg or if it doesn't match `conv`.
+ constexpr ConvParser ConsumeNextArg(char conv) const {
+ return SetArgs(args_.without_front()).SetError(!Contains(args_[0], conv));
+ }
+
+ // Verify that positional argument `i.value` matches `conv`.
+ // `error_` is set if `i.value` is not a valid argument or if it doesn't
+ // match.
+ constexpr ConvParser VerifyPositional(Integer i, char conv) const {
+ return SetFormat(i.format).SetError(!Contains(args_[i.value - 1], conv));
+ }
+
+ // Parse the position of the arg and store it in `arg_position_`.
+ constexpr ConvParser ParseArgPosition(Integer arg) const {
+ return SetFormat(arg.format).SetArgPosition(arg.value);
+ }
+
+ // Consume the flags.
+ constexpr ConvParser ParseFlags() const {
+ return SetFormat(ConsumeAnyOf(format_, "-+ #0"));
+ }
+
+ // Consume the width.
+ // If it is '*', we verify that it matches `args_`. `error_` is set if it
+ // doesn't match.
+ constexpr ConvParser ParseWidth() const {
+ return IsDigit(GetChar(format_, 0))
+ ? SetFormat(ParseDigits(format_).format)
+ : GetChar(format_, 0) == '*'
+ ? is_positional_
+ ? VerifyPositional(
+ ParsePositional(ConsumeFront(format_)), '*')
+ : SetFormat(ConsumeFront(format_))
+ .ConsumeNextArg('*')
+ : *this;
+ }
+
+ // Consume the precision.
+ // If it is '*', we verify that it matches `args_`. `error_` is set if it
+ // doesn't match.
+ constexpr ConvParser ParsePrecision() const {
+ return GetChar(format_, 0) != '.'
+ ? *this
+ : GetChar(format_, 1) == '*'
+ ? is_positional_
+ ? VerifyPositional(
+ ParsePositional(ConsumeFront(format_, 2)), '*')
+ : SetFormat(ConsumeFront(format_, 2))
+ .ConsumeNextArg('*')
+ : SetFormat(ParseDigits(ConsumeFront(format_)).format);
+ }
+
+ // Consume the length characters.
+ constexpr ConvParser ParseLength() const {
+ return SetFormat(ConsumeAnyOf(format_, "lLhjztq"));
+ }
+
+ // Consume the conversion character and verify that it matches `args_`.
+ // `error_` is set if it doesn't match.
+ constexpr ConvParser ParseConversion() const {
+ return is_positional_
+ ? VerifyPositional({ConsumeFront(format_), arg_position_},
+ GetChar(format_, 0))
+ : ConsumeNextArg(GetChar(format_, 0))
+ .SetFormat(ConsumeFront(format_));
+ }
+
+ constexpr ConvParser(string_view format, ConvList args, bool error,
+ int arg_position, bool is_positional)
+ : format_(format),
+ args_(args),
+ error_(error),
+ arg_position_(arg_position),
+ is_positional_(is_positional) {}
+
+ public:
+ constexpr ConvParser(string_view format, ConvList args, bool is_positional)
+ : format_(format),
+ args_(args),
+ error_(false),
+ arg_position_(0),
+ is_positional_(is_positional) {}
+
+ // Consume the whole conversion specifier.
+ // `format()` will be set to the character after the conversion character.
+ // `error()` will be set if any of the arguments do not match.
+ constexpr ConvParser Run() const {
+ return (is_positional_ ? ParseArgPosition(ParsePositional(format_)) : *this)
+ .ParseFlags()
+ .ParseWidth()
+ .ParsePrecision()
+ .ParseLength()
+ .ParseConversion();
+ }
+
+ constexpr string_view format() const { return format_; }
+ constexpr ConvList args() const { return args_; }
+ constexpr bool error() const { return error_; }
+ constexpr bool is_positional() const { return is_positional_; }
+
+ private:
+ string_view format_;
+ // Current list of arguments. If we are not in positional mode we will consume
+ // from the front.
+ ConvList args_;
+ bool error_;
+ // Holds the argument position of the conversion character, if we are in
+ // positional mode. Otherwise, it is unspecified.
+ int arg_position_;
+ // Whether we are in positional mode.
+ // It changes the behavior of '*' and where to find the converted argument.
+ bool is_positional_;
+};
+
+// Parses a whole format expression.
+// See FormatParser::Run().
+class FormatParser {
+ static constexpr bool FoundPercent(string_view format) {
+ return format.empty() ||
+ (GetChar(format, 0) == '%' && GetChar(format, 1) != '%');
+ }
+
+ // We use an inner function to increase the recursion limit.
+ // The inner function consumes up to `limit` characters on every run.
+ // This increases the limit from 512 to ~512*limit.
+ static constexpr string_view ConsumeNonPercentInner(string_view format,
+ int limit = 20) {
+ return FoundPercent(format) || !limit
+ ? format
+ : ConsumeNonPercentInner(
+ ConsumeFront(format, GetChar(format, 0) == '%' &&
+ GetChar(format, 1) == '%'
+ ? 2
+ : 1),
+ limit - 1);
+ }
+
+ // Consume characters until the next conversion spec %.
+ // It skips %%.
+ static constexpr string_view ConsumeNonPercent(string_view format) {
+ return FoundPercent(format)
+ ? format
+ : ConsumeNonPercent(ConsumeNonPercentInner(format));
+ }
+
+ static constexpr bool IsPositional(string_view format) {
+ return IsDigit(GetChar(format, 0)) ? IsPositional(ConsumeFront(format))
+ : GetChar(format, 0) == '$';
+ }
+
+ constexpr bool RunImpl(bool is_positional) const {
+ // In non-positional mode we require all arguments to be consumed.
+ // In positional mode just reaching the end of the format without errors is
+ // enough.
+ return (format_.empty() && (is_positional || args_.count == 0)) ||
+ (!format_.empty() &&
+ ValidateArg(
+ ConvParser(ConsumeFront(format_), args_, is_positional).Run()));
+ }
+
+ constexpr bool ValidateArg(ConvParser conv) const {
+ return !conv.error() && FormatParser(conv.format(), conv.args())
+ .RunImpl(conv.is_positional());
+ }
+
+ public:
+ constexpr FormatParser(string_view format, ConvList args)
+ : format_(ConsumeNonPercent(format)), args_(args) {}
+
+ // Runs the parser for `format` and `args`.
+ // It verifies that the format is valid and that all conversion specifiers
+ // match the arguments passed.
+ // In non-positional mode it also verfies that all arguments are consumed.
+ constexpr bool Run() const {
+ return RunImpl(!format_.empty() && IsPositional(ConsumeFront(format_)));
+ }
+
+ private:
+ string_view format_;
+ // Current list of arguments.
+ // If we are not in positional mode we will consume from the front and will
+ // have to be empty in the end.
+ ConvList args_;
+};
+
+template <Conv... C>
+constexpr bool ValidFormatImpl(string_view format) {
+ return FormatParser(format,
+ {ConvListT<sizeof...(C)>{{C...}}.list, sizeof...(C)})
+ .Run();
+}
+
+#endif // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_CHECKER_H_
diff --git a/absl/strings/internal/str_format/checker_test.cc b/absl/strings/internal/str_format/checker_test.cc
new file mode 100644
index 00000000..14d11ea8
--- /dev/null
+++ b/absl/strings/internal/str_format/checker_test.cc
@@ -0,0 +1,150 @@
+#include <string>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "absl/strings/str_format.h"
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+std::string ConvToString(Conv conv) {
+ std::string out;
+#define CONV_SET_CASE(c) \
+ if (Contains(conv, Conv::c)) out += #c;
+ ABSL_CONVERSION_CHARS_EXPAND_(CONV_SET_CASE, )
+#undef CONV_SET_CASE
+ if (Contains(conv, Conv::star)) out += "*";
+ return out;
+}
+
+TEST(StrFormatChecker, ArgumentToConv) {
+ Conv conv = ArgumentToConv<std::string>();
+ EXPECT_EQ(ConvToString(conv), "s");
+
+ conv = ArgumentToConv<const char*>();
+ EXPECT_EQ(ConvToString(conv), "sp");
+
+ conv = ArgumentToConv<double>();
+ EXPECT_EQ(ConvToString(conv), "fFeEgGaA");
+
+ conv = ArgumentToConv<int>();
+ EXPECT_EQ(ConvToString(conv), "cdiouxXfFeEgGaA*");
+
+ conv = ArgumentToConv<std::string*>();
+ EXPECT_EQ(ConvToString(conv), "p");
+}
+
+#if ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+struct Case {
+ bool result;
+ const char* format;
+};
+
+template <typename... Args>
+constexpr Case ValidFormat(const char* format) {
+ return {ValidFormatImpl<ArgumentToConv<Args>()...>(format), format};
+}
+
+TEST(StrFormatChecker, ValidFormat) {
+ // We want to make sure these expressions are constexpr and they have the
+ // expected value.
+ // If they are not constexpr the attribute will just ignore them and not give
+ // a compile time error.
+ enum e {};
+ enum class e2 {};
+ constexpr Case trues[] = {
+ ValidFormat<>("abc"), //
+
+ ValidFormat<e>("%d"), //
+ ValidFormat<e2>("%d"), //
+ ValidFormat<int>("%% %d"), //
+ ValidFormat<int>("%ld"), //
+ ValidFormat<int>("%lld"), //
+ ValidFormat<std::string>("%s"), //
+ ValidFormat<std::string>("%10s"), //
+ ValidFormat<int>("%.10x"), //
+ ValidFormat<int, int>("%*.3x"), //
+ ValidFormat<int>("%1.d"), //
+ ValidFormat<int>("%.d"), //
+ ValidFormat<int, double>("%d %g"), //
+ ValidFormat<int, std::string>("%*s"), //
+ ValidFormat<int, double>("%.*f"), //
+ ValidFormat<void (*)(), volatile int*>("%p %p"), //
+ ValidFormat<string_view, const char*, double, void*>(
+ "string_view=%s const char*=%s double=%f void*=%p)"),
+
+ ValidFormat<int>("%% %1$d"), //
+ ValidFormat<int>("%1$ld"), //
+ ValidFormat<int>("%1$lld"), //
+ ValidFormat<std::string>("%1$s"), //
+ ValidFormat<std::string>("%1$10s"), //
+ ValidFormat<int>("%1$.10x"), //
+ ValidFormat<int>("%1$*1$.*1$d"), //
+ ValidFormat<int, int>("%1$*2$.3x"), //
+ ValidFormat<int>("%1$1.d"), //
+ ValidFormat<int>("%1$.d"), //
+ ValidFormat<double, int>("%2$d %1$g"), //
+ ValidFormat<int, std::string>("%2$*1$s"), //
+ ValidFormat<int, double>("%2$.*1$f"), //
+ ValidFormat<void*, string_view, const char*, double>(
+ "string_view=%2$s const char*=%3$s double=%4$f void*=%1$p "
+ "repeat=%3$s)")};
+
+ for (Case c : trues) {
+ EXPECT_TRUE(c.result) << c.format;
+ }
+
+ constexpr Case falses[] = {
+ ValidFormat<int>(""), //
+
+ ValidFormat<e>("%s"), //
+ ValidFormat<e2>("%s"), //
+ ValidFormat<>("%s"), //
+ ValidFormat<>("%r"), //
+ ValidFormat<int>("%s"), //
+ ValidFormat<int>("%.1.d"), //
+ ValidFormat<int>("%*1d"), //
+ ValidFormat<int>("%1-d"), //
+ ValidFormat<std::string, int>("%*s"), //
+ ValidFormat<int>("%*d"), //
+ ValidFormat<std::string>("%p"), //
+ ValidFormat<int (*)(int)>("%d"), //
+
+ ValidFormat<>("%3$d"), //
+ ValidFormat<>("%1$r"), //
+ ValidFormat<int>("%1$s"), //
+ ValidFormat<int>("%1$.1.d"), //
+ ValidFormat<int>("%1$*2$1d"), //
+ ValidFormat<int>("%1$1-d"), //
+ ValidFormat<std::string, int>("%2$*1$s"), //
+ ValidFormat<std::string>("%1$p"),
+
+ ValidFormat<int, int>("%d %2$d"), //
+ };
+
+ for (Case c : falses) {
+ EXPECT_FALSE(c.result) << c.format;
+ }
+}
+
+TEST(StrFormatChecker, LongFormat) {
+#define CHARS_X_40 "1234567890123456789012345678901234567890"
+#define CHARS_X_400 \
+ CHARS_X_40 CHARS_X_40 CHARS_X_40 CHARS_X_40 CHARS_X_40 CHARS_X_40 CHARS_X_40 \
+ CHARS_X_40 CHARS_X_40 CHARS_X_40
+#define CHARS_X_4000 \
+ CHARS_X_400 CHARS_X_400 CHARS_X_400 CHARS_X_400 CHARS_X_400 CHARS_X_400 \
+ CHARS_X_400 CHARS_X_400 CHARS_X_400 CHARS_X_400
+ constexpr char long_format[] =
+ CHARS_X_4000 "%d" CHARS_X_4000 "%s" CHARS_X_4000;
+ constexpr bool is_valid = ValidFormat<int, std::string>(long_format).result;
+ EXPECT_TRUE(is_valid);
+}
+
+#endif // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+
+} // namespace
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/convert_test.cc b/absl/strings/internal/str_format/convert_test.cc
new file mode 100644
index 00000000..32f8a0f9
--- /dev/null
+++ b/absl/strings/internal/str_format/convert_test.cc
@@ -0,0 +1,575 @@
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <cmath>
+#include <string>
+
+#include "gtest/gtest.h"
+#include "absl/strings/internal/str_format/bind.h"
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+template <typename T, size_t N>
+size_t ArraySize(T (&)[N]) {
+ return N;
+}
+
+std::string LengthModFor(float) { return ""; }
+std::string LengthModFor(double) { return ""; }
+std::string LengthModFor(long double) { return "L"; }
+std::string LengthModFor(char) { return "hh"; }
+std::string LengthModFor(signed char) { return "hh"; }
+std::string LengthModFor(unsigned char) { return "hh"; }
+std::string LengthModFor(short) { return "h"; } // NOLINT
+std::string LengthModFor(unsigned short) { return "h"; } // NOLINT
+std::string LengthModFor(int) { return ""; }
+std::string LengthModFor(unsigned) { return ""; }
+std::string LengthModFor(long) { return "l"; } // NOLINT
+std::string LengthModFor(unsigned long) { return "l"; } // NOLINT
+std::string LengthModFor(long long) { return "ll"; } // NOLINT
+std::string LengthModFor(unsigned long long) { return "ll"; } // NOLINT
+
+std::string EscCharImpl(int v) {
+ if (isprint(v)) return std::string(1, static_cast<char>(v));
+ char buf[64];
+ int n = snprintf(buf, sizeof(buf), "\\%#.2x",
+ static_cast<unsigned>(v & 0xff));
+ assert(n > 0 && n < sizeof(buf));
+ return std::string(buf, n);
+}
+
+std::string Esc(char v) { return EscCharImpl(v); }
+std::string Esc(signed char v) { return EscCharImpl(v); }
+std::string Esc(unsigned char v) { return EscCharImpl(v); }
+
+template <typename T>
+std::string Esc(const T &v) {
+ std::ostringstream oss;
+ oss << v;
+ return oss.str();
+}
+
+void StrAppend(std::string *dst, const char *format, va_list ap) {
+ // First try with a small fixed size buffer
+ static const int kSpaceLength = 1024;
+ char space[kSpaceLength];
+
+ // It's possible for methods that use a va_list to invalidate
+ // the data in it upon use. The fix is to make a copy
+ // of the structure before using it and use that copy instead.
+ va_list backup_ap;
+ va_copy(backup_ap, ap);
+ int result = vsnprintf(space, kSpaceLength, format, backup_ap);
+ va_end(backup_ap);
+ if (result < kSpaceLength) {
+ if (result >= 0) {
+ // Normal case -- everything fit.
+ dst->append(space, result);
+ return;
+ }
+ if (result < 0) {
+ // Just an error.
+ return;
+ }
+ }
+
+ // Increase the buffer size to the size requested by vsnprintf,
+ // plus one for the closing \0.
+ int length = result + 1;
+ char *buf = new char[length];
+
+ // Restore the va_list before we use it again
+ va_copy(backup_ap, ap);
+ result = vsnprintf(buf, length, format, backup_ap);
+ va_end(backup_ap);
+
+ if (result >= 0 && result < length) {
+ // It fit
+ dst->append(buf, result);
+ }
+ delete[] buf;
+}
+
+std::string StrPrint(const char *format, ...) {
+ va_list ap;
+ va_start(ap, format);
+ std::string result;
+ StrAppend(&result, format, ap);
+ va_end(ap);
+ return result;
+}
+
+class FormatConvertTest : public ::testing::Test { };
+
+template <typename T>
+void TestStringConvert(const T& str) {
+ const FormatArgImpl args[] = {FormatArgImpl(str)};
+ struct Expectation {
+ const char *out;
+ const char *fmt;
+ };
+ const Expectation kExpect[] = {
+ {"hello", "%1$s" },
+ {"", "%1$.s" },
+ {"", "%1$.0s" },
+ {"h", "%1$.1s" },
+ {"he", "%1$.2s" },
+ {"hello", "%1$.10s" },
+ {" hello", "%1$6s" },
+ {" he", "%1$5.2s" },
+ {"he ", "%1$-5.2s" },
+ {"hello ", "%1$-6.10s" },
+ };
+ for (const Expectation &e : kExpect) {
+ UntypedFormatSpecImpl format(e.fmt);
+ EXPECT_EQ(e.out, FormatPack(format, absl::MakeSpan(args)));
+ }
+}
+
+TEST_F(FormatConvertTest, BasicString) {
+ TestStringConvert("hello"); // As char array.
+ TestStringConvert(static_cast<const char*>("hello"));
+ TestStringConvert(std::string("hello"));
+ TestStringConvert(string_view("hello"));
+}
+
+TEST_F(FormatConvertTest, NullString) {
+ const char* p = nullptr;
+ UntypedFormatSpecImpl format("%s");
+ EXPECT_EQ("", FormatPack(format, {FormatArgImpl(p)}));
+}
+
+TEST_F(FormatConvertTest, StringPrecision) {
+ // We cap at the precision.
+ char c = 'a';
+ const char* p = &c;
+ UntypedFormatSpecImpl format("%.1s");
+ EXPECT_EQ("a", FormatPack(format, {FormatArgImpl(p)}));
+
+ // We cap at the nul terminator.
+ p = "ABC";
+ UntypedFormatSpecImpl format2("%.10s");
+ EXPECT_EQ("ABC", FormatPack(format2, {FormatArgImpl(p)}));
+}
+
+TEST_F(FormatConvertTest, Pointer) {
+#if _MSC_VER
+ // MSVC's printf implementation prints pointers differently. We can't easily
+ // compare our implementation to theirs.
+ return;
+#endif
+ static int x = 0;
+ const int *xp = &x;
+ char c = 'h';
+ char *mcp = &c;
+ const char *cp = "hi";
+ const char *cnil = nullptr;
+ const int *inil = nullptr;
+ using VoidF = void (*)();
+ VoidF fp = [] {}, fnil = nullptr;
+ volatile char vc;
+ volatile char* vcp = &vc;
+ volatile char* vcnil = nullptr;
+ const FormatArgImpl args[] = {
+ FormatArgImpl(xp), FormatArgImpl(cp), FormatArgImpl(inil),
+ FormatArgImpl(cnil), FormatArgImpl(mcp), FormatArgImpl(fp),
+ FormatArgImpl(fnil), FormatArgImpl(vcp), FormatArgImpl(vcnil),
+ };
+ struct Expectation {
+ std::string out;
+ const char *fmt;
+ };
+ const Expectation kExpect[] = {
+ {StrPrint("%p", &x), "%p"},
+ {StrPrint("%20p", &x), "%20p"},
+ {StrPrint("%.1p", &x), "%.1p"},
+ {StrPrint("%.20p", &x), "%.20p"},
+ {StrPrint("%30.20p", &x), "%30.20p"},
+
+ {StrPrint("%-p", &x), "%-p"},
+ {StrPrint("%-20p", &x), "%-20p"},
+ {StrPrint("%-.1p", &x), "%-.1p"},
+ {StrPrint("%.20p", &x), "%.20p"},
+ {StrPrint("%-30.20p", &x), "%-30.20p"},
+
+ {StrPrint("%p", cp), "%2$p"}, // const char*
+ {"(nil)", "%3$p"}, // null const char *
+ {"(nil)", "%4$p"}, // null const int *
+ {StrPrint("%p", mcp), "%5$p"}, // nonconst char*
+
+ {StrPrint("%p", fp), "%6$p"}, // function pointer
+ {StrPrint("%p", vcp), "%8$p"}, // function pointer
+
+#ifndef __APPLE__
+ // Apple's printf differs here (0x0 vs. nil)
+ {StrPrint("%p", fnil), "%7$p"}, // null function pointer
+ {StrPrint("%p", vcnil), "%9$p"}, // null function pointer
+#endif
+ };
+ for (const Expectation &e : kExpect) {
+ UntypedFormatSpecImpl format(e.fmt);
+ EXPECT_EQ(e.out, FormatPack(format, absl::MakeSpan(args))) << e.fmt;
+ }
+}
+
+struct Cardinal {
+ enum Pos { k1 = 1, k2 = 2, k3 = 3 };
+ enum Neg { kM1 = -1, kM2 = -2, kM3 = -3 };
+};
+
+TEST_F(FormatConvertTest, Enum) {
+ const Cardinal::Pos k3 = Cardinal::k3;
+ const Cardinal::Neg km3 = Cardinal::kM3;
+ const FormatArgImpl args[] = {FormatArgImpl(k3), FormatArgImpl(km3)};
+ UntypedFormatSpecImpl format("%1$d");
+ UntypedFormatSpecImpl format2("%2$d");
+ EXPECT_EQ("3", FormatPack(format, absl::MakeSpan(args)));
+ EXPECT_EQ("-3", FormatPack(format2, absl::MakeSpan(args)));
+}
+
+template <typename T>
+class TypedFormatConvertTest : public FormatConvertTest { };
+
+TYPED_TEST_CASE_P(TypedFormatConvertTest);
+
+std::vector<std::string> AllFlagCombinations() {
+ const char kFlags[] = {'-', '#', '0', '+', ' '};
+ std::vector<std::string> result;
+ for (size_t fsi = 0; fsi < (1ull << ArraySize(kFlags)); ++fsi) {
+ std::string flag_set;
+ for (size_t fi = 0; fi < ArraySize(kFlags); ++fi)
+ if (fsi & (1ull << fi))
+ flag_set += kFlags[fi];
+ result.push_back(flag_set);
+ }
+ return result;
+}
+
+TYPED_TEST_P(TypedFormatConvertTest, AllIntsWithFlags) {
+ typedef TypeParam T;
+ typedef typename std::make_unsigned<T>::type UnsignedT;
+ using remove_volatile_t = typename std::remove_volatile<T>::type;
+ const T kMin = std::numeric_limits<remove_volatile_t>::min();
+ const T kMax = std::numeric_limits<remove_volatile_t>::max();
+ const T kVals[] = {
+ remove_volatile_t(1),
+ remove_volatile_t(2),
+ remove_volatile_t(3),
+ remove_volatile_t(123),
+ remove_volatile_t(-1),
+ remove_volatile_t(-2),
+ remove_volatile_t(-3),
+ remove_volatile_t(-123),
+ remove_volatile_t(0),
+ kMax - remove_volatile_t(1),
+ kMax,
+ kMin + remove_volatile_t(1),
+ kMin,
+ };
+ const char kConvChars[] = {'d', 'i', 'u', 'o', 'x', 'X'};
+ const std::string kWid[] = {"", "4", "10"};
+ const std::string kPrec[] = {"", ".", ".0", ".4", ".10"};
+
+ const std::vector<std::string> flag_sets = AllFlagCombinations();
+
+ for (size_t vi = 0; vi < ArraySize(kVals); ++vi) {
+ const T val = kVals[vi];
+ SCOPED_TRACE(Esc(val));
+ const FormatArgImpl args[] = {FormatArgImpl(val)};
+ for (size_t ci = 0; ci < ArraySize(kConvChars); ++ci) {
+ const char conv_char = kConvChars[ci];
+ for (size_t fsi = 0; fsi < flag_sets.size(); ++fsi) {
+ const std::string &flag_set = flag_sets[fsi];
+ for (size_t wi = 0; wi < ArraySize(kWid); ++wi) {
+ const std::string &wid = kWid[wi];
+ for (size_t pi = 0; pi < ArraySize(kPrec); ++pi) {
+ const std::string &prec = kPrec[pi];
+
+ const bool is_signed_conv = (conv_char == 'd' || conv_char == 'i');
+ const bool is_unsigned_to_signed =
+ !std::is_signed<T>::value && is_signed_conv;
+ // Don't consider sign-related flags '+' and ' ' when doing
+ // unsigned to signed conversions.
+ if (is_unsigned_to_signed &&
+ flag_set.find_first_of("+ ") != std::string::npos) {
+ continue;
+ }
+
+ std::string new_fmt("%");
+ new_fmt += flag_set;
+ new_fmt += wid;
+ new_fmt += prec;
+ // old and new always agree up to here.
+ std::string old_fmt = new_fmt;
+ new_fmt += conv_char;
+ std::string old_result;
+ if (is_unsigned_to_signed) {
+ // don't expect agreement on unsigned formatted as signed,
+ // as printf can't do that conversion properly. For those
+ // cases, we do expect agreement with printf with a "%u"
+ // and the unsigned equivalent of 'val'.
+ UnsignedT uval = val;
+ old_fmt += LengthModFor(uval);
+ old_fmt += "u";
+ old_result = StrPrint(old_fmt.c_str(), uval);
+ } else {
+ old_fmt += LengthModFor(val);
+ old_fmt += conv_char;
+ old_result = StrPrint(old_fmt.c_str(), val);
+ }
+
+ SCOPED_TRACE(std::string() + " old_fmt: \"" + old_fmt +
+ "\"'"
+ " new_fmt: \"" +
+ new_fmt + "\"");
+ UntypedFormatSpecImpl format(new_fmt);
+ EXPECT_EQ(old_result, FormatPack(format, absl::MakeSpan(args)));
+ }
+ }
+ }
+ }
+ }
+}
+
+TYPED_TEST_P(TypedFormatConvertTest, Char) {
+ typedef TypeParam T;
+ using remove_volatile_t = typename std::remove_volatile<T>::type;
+ static const T kMin = std::numeric_limits<remove_volatile_t>::min();
+ static const T kMax = std::numeric_limits<remove_volatile_t>::max();
+ T kVals[] = {
+ remove_volatile_t(1), remove_volatile_t(2), remove_volatile_t(10),
+ remove_volatile_t(-1), remove_volatile_t(-2), remove_volatile_t(-10),
+ remove_volatile_t(0),
+ kMin + remove_volatile_t(1), kMin,
+ kMax - remove_volatile_t(1), kMax
+ };
+ for (const T &c : kVals) {
+ const FormatArgImpl args[] = {FormatArgImpl(c)};
+ UntypedFormatSpecImpl format("%c");
+ EXPECT_EQ(StrPrint("%c", c), FormatPack(format, absl::MakeSpan(args)));
+ }
+}
+
+REGISTER_TYPED_TEST_CASE_P(TypedFormatConvertTest, AllIntsWithFlags, Char);
+
+typedef ::testing::Types<
+ int, unsigned, volatile int,
+ short, unsigned short,
+ long, unsigned long,
+ long long, unsigned long long,
+ signed char, unsigned char, char>
+ AllIntTypes;
+INSTANTIATE_TYPED_TEST_CASE_P(TypedFormatConvertTestWithAllIntTypes,
+ TypedFormatConvertTest, AllIntTypes);
+TEST_F(FormatConvertTest, Uint128) {
+ absl::uint128 v = static_cast<absl::uint128>(0x1234567890abcdef) * 1979;
+ absl::uint128 max = absl::Uint128Max();
+ const FormatArgImpl args[] = {FormatArgImpl(v), FormatArgImpl(max)};
+
+ struct Case {
+ const char* format;
+ const char* expected;
+ } cases[] = {
+ {"%1$d", "2595989796776606496405"},
+ {"%1$30d", " 2595989796776606496405"},
+ {"%1$-30d", "2595989796776606496405 "},
+ {"%1$u", "2595989796776606496405"},
+ {"%1$x", "8cba9876066020f695"},
+ {"%2$d", "340282366920938463463374607431768211455"},
+ {"%2$u", "340282366920938463463374607431768211455"},
+ {"%2$x", "ffffffffffffffffffffffffffffffff"},
+ };
+
+ for (auto c : cases) {
+ UntypedFormatSpecImpl format(c.format);
+ EXPECT_EQ(c.expected, FormatPack(format, absl::MakeSpan(args)));
+ }
+}
+
+TEST_F(FormatConvertTest, Float) {
+#if _MSC_VER
+ // MSVC has a different rounding policy than us so we can't test our
+ // implementation against the native one there.
+ return;
+#endif // _MSC_VER
+
+ const char *const kFormats[] = {
+ "%", "%.3", "%8.5", "%9", "%.60", "%.30", "%03", "%+",
+ "% ", "%-10", "%#15.3", "%#.0", "%.0", "%1$*2$", "%1$.*2$"};
+
+ std::vector<double> doubles = {0.0,
+ -0.0,
+ .99999999999999,
+ 99999999999999.,
+ std::numeric_limits<double>::max(),
+ -std::numeric_limits<double>::max(),
+ std::numeric_limits<double>::min(),
+ -std::numeric_limits<double>::min(),
+ std::numeric_limits<double>::lowest(),
+ -std::numeric_limits<double>::lowest(),
+ std::numeric_limits<double>::epsilon(),
+ std::numeric_limits<double>::epsilon() + 1,
+ std::numeric_limits<double>::infinity(),
+ -std::numeric_limits<double>::infinity()};
+
+#ifndef __APPLE__
+ // Apple formats NaN differently (+nan) vs. (nan)
+ doubles.push_back(std::nan(""));
+#endif
+
+ // Some regression tests.
+ doubles.push_back(0.99999999999999989);
+
+ if (std::numeric_limits<double>::has_denorm != std::denorm_absent) {
+ doubles.push_back(std::numeric_limits<double>::denorm_min());
+ doubles.push_back(-std::numeric_limits<double>::denorm_min());
+ }
+
+ for (double base :
+ {1., 12., 123., 1234., 12345., 123456., 1234567., 12345678., 123456789.,
+ 1234567890., 12345678901., 123456789012., 1234567890123.}) {
+ for (int exp = -123; exp <= 123; ++exp) {
+ for (int sign : {1, -1}) {
+ doubles.push_back(sign * std::ldexp(base, exp));
+ }
+ }
+ }
+
+ for (const char *fmt : kFormats) {
+ for (char f : {'f', 'F', //
+ 'g', 'G', //
+ 'a', 'A', //
+ 'e', 'E'}) {
+ std::string fmt_str = std::string(fmt) + f;
+ for (double d : doubles) {
+ int i = -10;
+ FormatArgImpl args[2] = {FormatArgImpl(d), FormatArgImpl(i)};
+ UntypedFormatSpecImpl format(fmt_str);
+ // We use ASSERT_EQ here because failures are usually correlated and a
+ // bug would print way too many failed expectations causing the test to
+ // time out.
+ ASSERT_EQ(StrPrint(fmt_str.c_str(), d, i),
+ FormatPack(format, absl::MakeSpan(args)))
+ << fmt_str << " " << StrPrint("%.18g", d) << " "
+ << StrPrint("%.999f", d);
+ }
+ }
+ }
+}
+
+TEST_F(FormatConvertTest, LongDouble) {
+ const char *const kFormats[] = {"%", "%.3", "%8.5", "%9",
+ "%.60", "%+", "% ", "%-10"};
+
+ // This value is not representable in double, but it is in long double that
+ // uses the extended format.
+ // This is to verify that we are not truncating the value mistakenly through a
+ // double.
+ long double very_precise = 10000000000000000.25L;
+
+ std::vector<long double> doubles = {
+ 0.0,
+ -0.0,
+ very_precise,
+ 1 / very_precise,
+ std::numeric_limits<long double>::max(),
+ -std::numeric_limits<long double>::max(),
+ std::numeric_limits<long double>::min(),
+ -std::numeric_limits<long double>::min(),
+ std::numeric_limits<long double>::infinity(),
+ -std::numeric_limits<long double>::infinity()};
+
+ for (const char *fmt : kFormats) {
+ for (char f : {'f', 'F', //
+ 'g', 'G', //
+ 'a', 'A', //
+ 'e', 'E'}) {
+ std::string fmt_str = std::string(fmt) + 'L' + f;
+ for (auto d : doubles) {
+ FormatArgImpl arg(d);
+ UntypedFormatSpecImpl format(fmt_str);
+ // We use ASSERT_EQ here because failures are usually correlated and a
+ // bug would print way too many failed expectations causing the test to
+ // time out.
+ ASSERT_EQ(StrPrint(fmt_str.c_str(), d),
+ FormatPack(format, {&arg, 1}))
+ << fmt_str << " " << StrPrint("%.18Lg", d) << " "
+ << StrPrint("%.999Lf", d);
+ }
+ }
+ }
+}
+
+TEST_F(FormatConvertTest, IntAsFloat) {
+ const int kMin = std::numeric_limits<int>::min();
+ const int kMax = std::numeric_limits<int>::max();
+ const int ia[] = {
+ 1, 2, 3, 123,
+ -1, -2, -3, -123,
+ 0, kMax - 1, kMax, kMin + 1, kMin };
+ for (const int fx : ia) {
+ SCOPED_TRACE(fx);
+ const FormatArgImpl args[] = {FormatArgImpl(fx)};
+ struct Expectation {
+ int line;
+ std::string out;
+ const char *fmt;
+ };
+ const double dx = static_cast<double>(fx);
+ const Expectation kExpect[] = {
+ { __LINE__, StrPrint("%f", dx), "%f" },
+ { __LINE__, StrPrint("%12f", dx), "%12f" },
+ { __LINE__, StrPrint("%.12f", dx), "%.12f" },
+ { __LINE__, StrPrint("%12a", dx), "%12a" },
+ { __LINE__, StrPrint("%.12a", dx), "%.12a" },
+ };
+ for (const Expectation &e : kExpect) {
+ SCOPED_TRACE(e.line);
+ SCOPED_TRACE(e.fmt);
+ UntypedFormatSpecImpl format(e.fmt);
+ EXPECT_EQ(e.out, FormatPack(format, absl::MakeSpan(args)));
+ }
+ }
+}
+
+template <typename T>
+bool FormatFails(const char* test_format, T value) {
+ std::string format_string = std::string("<<") + test_format + ">>";
+ UntypedFormatSpecImpl format(format_string);
+
+ int one = 1;
+ const FormatArgImpl args[] = {FormatArgImpl(value), FormatArgImpl(one)};
+ EXPECT_EQ(FormatPack(format, absl::MakeSpan(args)), "")
+ << "format=" << test_format << " value=" << value;
+ return FormatPack(format, absl::MakeSpan(args)).empty();
+}
+
+TEST_F(FormatConvertTest, ExpectedFailures) {
+ // Int input
+ EXPECT_TRUE(FormatFails("%p", 1));
+ EXPECT_TRUE(FormatFails("%s", 1));
+ EXPECT_TRUE(FormatFails("%n", 1));
+
+ // Double input
+ EXPECT_TRUE(FormatFails("%p", 1.));
+ EXPECT_TRUE(FormatFails("%s", 1.));
+ EXPECT_TRUE(FormatFails("%n", 1.));
+ EXPECT_TRUE(FormatFails("%c", 1.));
+ EXPECT_TRUE(FormatFails("%d", 1.));
+ EXPECT_TRUE(FormatFails("%x", 1.));
+ EXPECT_TRUE(FormatFails("%*d", 1.));
+
+ // String input
+ EXPECT_TRUE(FormatFails("%n", ""));
+ EXPECT_TRUE(FormatFails("%c", ""));
+ EXPECT_TRUE(FormatFails("%d", ""));
+ EXPECT_TRUE(FormatFails("%x", ""));
+ EXPECT_TRUE(FormatFails("%f", ""));
+ EXPECT_TRUE(FormatFails("%*d", ""));
+}
+
+} // namespace
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/extension.cc b/absl/strings/internal/str_format/extension.cc
new file mode 100644
index 00000000..c2174703
--- /dev/null
+++ b/absl/strings/internal/str_format/extension.cc
@@ -0,0 +1,84 @@
+//
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/strings/internal/str_format/extension.h"
+
+#include <errno.h>
+#include <algorithm>
+#include <string>
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+// clang-format off
+#define ABSL_LENGTH_MODS_EXPAND_ \
+ X_VAL(h) X_SEP \
+ X_VAL(hh) X_SEP \
+ X_VAL(l) X_SEP \
+ X_VAL(ll) X_SEP \
+ X_VAL(L) X_SEP \
+ X_VAL(j) X_SEP \
+ X_VAL(z) X_SEP \
+ X_VAL(t) X_SEP \
+ X_VAL(q)
+// clang-format on
+} // namespace
+
+const LengthMod::Spec LengthMod::kSpecs[] = {
+#define X_VAL(id) { LengthMod::id, #id, strlen(#id) }
+#define X_SEP ,
+ ABSL_LENGTH_MODS_EXPAND_, {LengthMod::none, "", 0}
+#undef X_VAL
+#undef X_SEP
+};
+
+const ConversionChar::Spec ConversionChar::kSpecs[] = {
+#define X_VAL(id) { ConversionChar::id, #id[0] }
+#define X_SEP ,
+ ABSL_CONVERSION_CHARS_EXPAND_(X_VAL, X_SEP),
+ {ConversionChar::none, '\0'},
+#undef X_VAL
+#undef X_SEP
+};
+
+std::string Flags::ToString() const {
+ std::string s;
+ s.append(left ? "-" : "");
+ s.append(show_pos ? "+" : "");
+ s.append(sign_col ? " " : "");
+ s.append(alt ? "#" : "");
+ s.append(zero ? "0" : "");
+ return s;
+}
+
+const size_t LengthMod::kNumValues;
+
+const size_t ConversionChar::kNumValues;
+
+bool FormatSinkImpl::PutPaddedString(string_view v, int w, int p, bool l) {
+ size_t space_remaining = 0;
+ if (w >= 0) space_remaining = w;
+ size_t n = v.size();
+ if (p >= 0) n = std::min(n, static_cast<size_t>(p));
+ string_view shown(v.data(), n);
+ space_remaining = Excess(shown.size(), space_remaining);
+ if (!l) Append(space_remaining, ' ');
+ Append(shown);
+ if (l) Append(space_remaining, ' ');
+ return true;
+}
+
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/extension.h b/absl/strings/internal/str_format/extension.h
new file mode 100644
index 00000000..810330b9
--- /dev/null
+++ b/absl/strings/internal/str_format/extension.h
@@ -0,0 +1,406 @@
+//
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+//
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_EXTENSION_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_EXTENSION_H_
+
+#include <limits.h>
+#include <cstring>
+#include <ostream>
+
+#include "absl/base/port.h"
+#include "absl/strings/internal/str_format/output.h"
+#include "absl/strings/string_view.h"
+
+class Cord;
+
+namespace absl {
+
+namespace str_format_internal {
+
+class FormatRawSinkImpl {
+ public:
+ // Implicitly convert from any type that provides the hook function as
+ // described above.
+ template <typename T, decltype(str_format_internal::InvokeFlush(
+ std::declval<T*>(), string_view()))* = nullptr>
+ FormatRawSinkImpl(T* raw) // NOLINT
+ : sink_(raw), write_(&FormatRawSinkImpl::Flush<T>) {}
+
+ void Write(string_view s) { write_(sink_, s); }
+
+ template <typename T>
+ static FormatRawSinkImpl Extract(T s) {
+ return s.sink_;
+ }
+
+ private:
+ template <typename T>
+ static void Flush(void* r, string_view s) {
+ str_format_internal::InvokeFlush(static_cast<T*>(r), s);
+ }
+
+ void* sink_;
+ void (*write_)(void*, string_view);
+};
+
+// An abstraction to which conversions write their std::string data.
+class FormatSinkImpl {
+ public:
+ explicit FormatSinkImpl(FormatRawSinkImpl raw) : raw_(raw) {}
+
+ ~FormatSinkImpl() { Flush(); }
+
+ void Flush() {
+ raw_.Write(string_view(buf_, pos_ - buf_));
+ pos_ = buf_;
+ }
+
+ void Append(size_t n, char c) {
+ if (n == 0) return;
+ size_ += n;
+ auto raw_append = [&](size_t count) {
+ memset(pos_, c, count);
+ pos_ += count;
+ };
+ while (n > Avail()) {
+ n -= Avail();
+ if (Avail() > 0) {
+ raw_append(Avail());
+ }
+ Flush();
+ }
+ raw_append(n);
+ }
+
+ void Append(string_view v) {
+ size_t n = v.size();
+ if (n == 0) return;
+ size_ += n;
+ if (n >= Avail()) {
+ Flush();
+ raw_.Write(v);
+ return;
+ }
+ memcpy(pos_, v.data(), n);
+ pos_ += n;
+ }
+
+ size_t size() const { return size_; }
+
+ // Put 'v' to 'sink' with specified width, precision, and left flag.
+ bool PutPaddedString(string_view v, int w, int p, bool l);
+
+ template <typename T>
+ T Wrap() {
+ return T(this);
+ }
+
+ template <typename T>
+ static FormatSinkImpl* Extract(T* s) {
+ return s->sink_;
+ }
+
+ private:
+ size_t Avail() const { return buf_ + sizeof(buf_) - pos_; }
+
+ FormatRawSinkImpl raw_;
+ size_t size_ = 0;
+ char* pos_ = buf_;
+ char buf_[1024];
+};
+
+struct Flags {
+ bool basic : 1; // fastest conversion: no flags, width, or precision
+ bool left : 1; // "-"
+ bool show_pos : 1; // "+"
+ bool sign_col : 1; // " "
+ bool alt : 1; // "#"
+ bool zero : 1; // "0"
+ std::string ToString() const;
+ friend std::ostream& operator<<(std::ostream& os, const Flags& v) {
+ return os << v.ToString();
+ }
+};
+
+struct LengthMod {
+ public:
+ enum Id : uint8_t {
+ h, hh, l, ll, L, j, z, t, q, none
+ };
+ static const size_t kNumValues = none + 1;
+
+ LengthMod() : id_(none) {}
+
+ // Index into the opaque array of LengthMod enums.
+ // Requires: i < kNumValues
+ static LengthMod FromIndex(size_t i) {
+ return LengthMod(kSpecs[i].value);
+ }
+
+ static LengthMod FromId(Id id) { return LengthMod(id); }
+
+ // The length modifier std::string associated with a specified LengthMod.
+ string_view name() const {
+ const Spec& spec = kSpecs[id_];
+ return {spec.name, spec.name_length};
+ }
+
+ Id id() const { return id_; }
+
+ friend bool operator==(const LengthMod& a, const LengthMod& b) {
+ return a.id() == b.id();
+ }
+ friend bool operator!=(const LengthMod& a, const LengthMod& b) {
+ return !(a == b);
+ }
+ friend std::ostream& operator<<(std::ostream& os, const LengthMod& v) {
+ return os << v.name();
+ }
+
+ private:
+ struct Spec {
+ Id value;
+ const char *name;
+ size_t name_length;
+ };
+ static const Spec kSpecs[];
+
+ explicit LengthMod(Id id) : id_(id) {}
+
+ Id id_;
+};
+
+// clang-format off
+#define ABSL_CONVERSION_CHARS_EXPAND_(X_VAL, X_SEP) \
+ /* text */ \
+ X_VAL(c) X_SEP X_VAL(C) X_SEP X_VAL(s) X_SEP X_VAL(S) X_SEP \
+ /* ints */ \
+ X_VAL(d) X_SEP X_VAL(i) X_SEP X_VAL(o) X_SEP \
+ X_VAL(u) X_SEP X_VAL(x) X_SEP X_VAL(X) X_SEP \
+ /* floats */ \
+ X_VAL(f) X_SEP X_VAL(F) X_SEP X_VAL(e) X_SEP X_VAL(E) X_SEP \
+ X_VAL(g) X_SEP X_VAL(G) X_SEP X_VAL(a) X_SEP X_VAL(A) X_SEP \
+ /* misc */ \
+ X_VAL(n) X_SEP X_VAL(p)
+// clang-format on
+
+struct ConversionChar {
+ public:
+ enum Id : uint8_t {
+ c, C, s, S, // text
+ d, i, o, u, x, X, // int
+ f, F, e, E, g, G, a, A, // float
+ n, p, // misc
+ none
+ };
+ static const size_t kNumValues = none + 1;
+
+ ConversionChar() : id_(none) {}
+
+ public:
+ // Index into the opaque array of ConversionChar enums.
+ // Requires: i < kNumValues
+ static ConversionChar FromIndex(size_t i) {
+ return ConversionChar(kSpecs[i].value);
+ }
+
+ static ConversionChar FromChar(char c) {
+ ConversionChar::Id out_id = ConversionChar::none;
+ switch (c) {
+#define X_VAL(id) \
+ case #id[0]: \
+ out_id = ConversionChar::id; \
+ break;
+ ABSL_CONVERSION_CHARS_EXPAND_(X_VAL, )
+#undef X_VAL
+ default:
+ break;
+ }
+ return ConversionChar(out_id);
+ }
+
+ static ConversionChar FromId(Id id) { return ConversionChar(id); }
+ Id id() const { return id_; }
+
+ int radix() const {
+ switch (id()) {
+ case x: case X: case a: case A: case p: return 16;
+ case o: return 8;
+ default: return 10;
+ }
+ }
+
+ bool upper() const {
+ switch (id()) {
+ case X: case F: case E: case G: case A: return true;
+ default: return false;
+ }
+ }
+
+ bool is_signed() const {
+ switch (id()) {
+ case d: case i: return true;
+ default: return false;
+ }
+ }
+
+ bool is_integral() const {
+ switch (id()) {
+ case d: case i: case u: case o: case x: case X:
+ return true;
+ default: return false;
+ }
+ }
+
+ bool is_float() const {
+ switch (id()) {
+ case a: case e: case f: case g: case A: case E: case F: case G:
+ return true;
+ default: return false;
+ }
+ }
+
+ bool IsValid() const { return id() != none; }
+
+ // The associated char.
+ char Char() const { return kSpecs[id_].name; }
+
+ friend bool operator==(const ConversionChar& a, const ConversionChar& b) {
+ return a.id() == b.id();
+ }
+ friend bool operator!=(const ConversionChar& a, const ConversionChar& b) {
+ return !(a == b);
+ }
+ friend std::ostream& operator<<(std::ostream& os, const ConversionChar& v) {
+ char c = v.Char();
+ if (!c) c = '?';
+ return os << c;
+ }
+
+ private:
+ struct Spec {
+ Id value;
+ char name;
+ };
+ static const Spec kSpecs[];
+
+ explicit ConversionChar(Id id) : id_(id) {}
+
+ Id id_;
+};
+
+class ConversionSpec {
+ public:
+ Flags flags() const { return flags_; }
+ LengthMod length_mod() const { return length_mod_; }
+ ConversionChar conv() const { return conv_; }
+
+ // Returns the specified width. If width is unspecfied, it returns a negative
+ // value.
+ int width() const { return width_; }
+ // Returns the specified precision. If precision is unspecfied, it returns a
+ // negative value.
+ int precision() const { return precision_; }
+
+ void set_flags(Flags f) { flags_ = f; }
+ void set_length_mod(LengthMod lm) { length_mod_ = lm; }
+ void set_conv(ConversionChar c) { conv_ = c; }
+ void set_width(int w) { width_ = w; }
+ void set_precision(int p) { precision_ = p; }
+ void set_left(bool b) { flags_.left = b; }
+
+ private:
+ Flags flags_;
+ LengthMod length_mod_;
+ ConversionChar conv_;
+ int width_;
+ int precision_;
+};
+
+constexpr uint64_t ConversionCharToConvValue(char conv) {
+ return
+#define CONV_SET_CASE(c) \
+ conv == #c[0] ? (uint64_t{1} << (1 + ConversionChar::Id::c)):
+ ABSL_CONVERSION_CHARS_EXPAND_(CONV_SET_CASE, )
+#undef CONV_SET_CASE
+ conv == '*'
+ ? 1
+ : 0;
+}
+
+enum class Conv : uint64_t {
+#define CONV_SET_CASE(c) c = ConversionCharToConvValue(#c[0]),
+ ABSL_CONVERSION_CHARS_EXPAND_(CONV_SET_CASE, )
+#undef CONV_SET_CASE
+
+ // Used for width/precision '*' specification.
+ star = ConversionCharToConvValue('*'),
+
+ // Some predefined values:
+ integral = d | i | u | o | x | X,
+ floating = a | e | f | g | A | E | F | G,
+ numeric = integral | floating,
+ string = s, // absl:ignore(std::string)
+ pointer = p
+};
+
+// Type safe OR operator.
+// We need this for two reasons:
+// 1. operator| on enums makes them decay to integers and the result is an
+// integer. We need the result to stay as an enum.
+// 2. We use "enum class" which would not work even if we accepted the decay.
+constexpr Conv operator|(Conv a, Conv b) {
+ return Conv(static_cast<uint64_t>(a) | static_cast<uint64_t>(b));
+}
+
+// Get a conversion with a single character in it.
+constexpr Conv ConversionCharToConv(char c) {
+ return Conv(ConversionCharToConvValue(c));
+}
+
+// Checks whether `c` exists in `set`.
+constexpr bool Contains(Conv set, char c) {
+ return (static_cast<uint64_t>(set) & ConversionCharToConvValue(c)) != 0;
+}
+
+// Checks whether all the characters in `c` are contained in `set`
+constexpr bool Contains(Conv set, Conv c) {
+ return (static_cast<uint64_t>(set) & static_cast<uint64_t>(c)) ==
+ static_cast<uint64_t>(c);
+}
+
+// Return type of the AbslFormatConvert() functions.
+// The Conv template parameter is used to inform the framework of what
+// conversion characters are supported by that AbslFormatConvert routine.
+template <Conv C>
+struct ConvertResult {
+ static constexpr Conv kConv = C;
+ bool value;
+};
+template <Conv C>
+constexpr Conv ConvertResult<C>::kConv;
+
+// Return capacity - used, clipped to a minimum of 0.
+inline size_t Excess(size_t used, size_t capacity) {
+ return used < capacity ? capacity - used : 0;
+}
+
+} // namespace str_format_internal
+
+} // namespace absl
+
+#endif // ABSL_STRINGS_STR_FORMAT_EXTENSION_H_
diff --git a/absl/strings/internal/str_format/extension_test.cc b/absl/strings/internal/str_format/extension_test.cc
new file mode 100644
index 00000000..224fc923
--- /dev/null
+++ b/absl/strings/internal/str_format/extension_test.cc
@@ -0,0 +1,65 @@
+//
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "absl/strings/internal/str_format/extension.h"
+
+#include <random>
+#include <string>
+#include "absl/strings/str_format.h"
+
+#include "gtest/gtest.h"
+
+namespace {
+
+std::string MakeRandomString(size_t len) {
+ std::random_device rd;
+ std::mt19937 gen(rd());
+ std::uniform_int_distribution<> dis('a', 'z');
+ std::string s(len, '0');
+ for (char& c : s) {
+ c = dis(gen);
+ }
+ return s;
+}
+
+TEST(FormatExtensionTest, SinkAppendSubstring) {
+ for (size_t chunk_size : {1, 10, 100, 1000, 10000}) {
+ std::string expected, actual;
+ absl::str_format_internal::FormatSinkImpl sink(&actual);
+ for (size_t chunks = 0; chunks < 10; ++chunks) {
+ std::string rand = MakeRandomString(chunk_size);
+ expected += rand;
+ sink.Append(rand);
+ }
+ sink.Flush();
+ EXPECT_EQ(actual, expected);
+ }
+}
+
+TEST(FormatExtensionTest, SinkAppendChars) {
+ for (size_t chunk_size : {1, 10, 100, 1000, 10000}) {
+ std::string expected, actual;
+ absl::str_format_internal::FormatSinkImpl sink(&actual);
+ for (size_t chunks = 0; chunks < 10; ++chunks) {
+ std::string rand = MakeRandomString(1);
+ expected.append(chunk_size, rand[0]);
+ sink.Append(chunk_size, rand[0]);
+ }
+ sink.Flush();
+ EXPECT_EQ(actual, expected);
+ }
+}
+} // namespace
diff --git a/absl/strings/internal/str_format/float_conversion.cc b/absl/strings/internal/str_format/float_conversion.cc
new file mode 100644
index 00000000..37952b46
--- /dev/null
+++ b/absl/strings/internal/str_format/float_conversion.cc
@@ -0,0 +1,476 @@
+#include "absl/strings/internal/str_format/float_conversion.h"
+
+#include <string.h>
+#include <algorithm>
+#include <cassert>
+#include <cmath>
+#include <string>
+
+namespace absl {
+namespace str_format_internal {
+
+namespace {
+
+char *CopyStringTo(string_view v, char *out) {
+ std::memcpy(out, v.data(), v.size());
+ return out + v.size();
+}
+
+template <typename Float>
+bool FallbackToSnprintf(const Float v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ int w = conv.width() >= 0 ? conv.width() : 0;
+ int p = conv.precision() >= 0 ? conv.precision() : -1;
+ char fmt[32];
+ {
+ char *fp = fmt;
+ *fp++ = '%';
+ fp = CopyStringTo(conv.flags().ToString(), fp);
+ fp = CopyStringTo("*.*", fp);
+ if (std::is_same<long double, Float>()) {
+ *fp++ = 'L';
+ }
+ *fp++ = conv.conv().Char();
+ *fp = 0;
+ assert(fp < fmt + sizeof(fmt));
+ }
+ std::string space(512, '\0');
+ string_view result;
+ while (true) {
+ int n = snprintf(&space[0], space.size(), fmt, w, p, v);
+ if (n < 0) return false;
+ if (static_cast<size_t>(n) < space.size()) {
+ result = string_view(space.data(), n);
+ break;
+ }
+ space.resize(n + 1);
+ }
+ sink->Append(result);
+ return true;
+}
+
+// 128-bits in decimal: ceil(128*log(2)/log(10))
+// or std::numeric_limits<__uint128_t>::digits10
+constexpr int kMaxFixedPrecision = 39;
+
+constexpr int kBufferLength = /*sign*/ 1 +
+ /*integer*/ kMaxFixedPrecision +
+ /*point*/ 1 +
+ /*fraction*/ kMaxFixedPrecision +
+ /*exponent e+123*/ 5;
+
+struct Buffer {
+ void push_front(char c) {
+ assert(begin > data);
+ *--begin = c;
+ }
+ void push_back(char c) {
+ assert(end < data + sizeof(data));
+ *end++ = c;
+ }
+ void pop_back() {
+ assert(begin < end);
+ --end;
+ }
+
+ char &back() {
+ assert(begin < end);
+ return end[-1];
+ }
+
+ char last_digit() const { return end[-1] == '.' ? end[-2] : end[-1]; }
+
+ int size() const { return static_cast<int>(end - begin); }
+
+ char data[kBufferLength];
+ char *begin;
+ char *end;
+};
+
+enum class FormatStyle { Fixed, Precision };
+
+// If the value is Inf or Nan, print it and return true.
+// Otherwise, return false.
+template <typename Float>
+bool ConvertNonNumericFloats(char sign_char, Float v,
+ const ConversionSpec &conv, FormatSinkImpl *sink) {
+ char text[4], *ptr = text;
+ if (sign_char) *ptr++ = sign_char;
+ if (std::isnan(v)) {
+ ptr = std::copy_n(conv.conv().upper() ? "NAN" : "nan", 3, ptr);
+ } else if (std::isinf(v)) {
+ ptr = std::copy_n(conv.conv().upper() ? "INF" : "inf", 3, ptr);
+ } else {
+ return false;
+ }
+
+ return sink->PutPaddedString(string_view(text, ptr - text), conv.width(), -1,
+ conv.flags().left);
+}
+
+// Round up the last digit of the value.
+// It will carry over and potentially overflow. 'exp' will be adjusted in that
+// case.
+template <FormatStyle mode>
+void RoundUp(Buffer *buffer, int *exp) {
+ char *p = &buffer->back();
+ while (p >= buffer->begin && (*p == '9' || *p == '.')) {
+ if (*p == '9') *p = '0';
+ --p;
+ }
+
+ if (p < buffer->begin) {
+ *p = '1';
+ buffer->begin = p;
+ if (mode == FormatStyle::Precision) {
+ std::swap(p[1], p[2]); // move the .
+ ++*exp;
+ buffer->pop_back();
+ }
+ } else {
+ ++*p;
+ }
+}
+
+void PrintExponent(int exp, char e, Buffer *out) {
+ out->push_back(e);
+ if (exp < 0) {
+ out->push_back('-');
+ exp = -exp;
+ } else {
+ out->push_back('+');
+ }
+ // Exponent digits.
+ if (exp > 99) {
+ out->push_back(exp / 100 + '0');
+ out->push_back(exp / 10 % 10 + '0');
+ out->push_back(exp % 10 + '0');
+ } else {
+ out->push_back(exp / 10 + '0');
+ out->push_back(exp % 10 + '0');
+ }
+}
+
+template <typename Float, typename Int>
+constexpr bool CanFitMantissa() {
+ return std::numeric_limits<Float>::digits <= std::numeric_limits<Int>::digits;
+}
+
+template <typename Float>
+struct Decomposed {
+ Float mantissa;
+ int exponent;
+};
+
+// Decompose the double into an integer mantissa and an exponent.
+template <typename Float>
+Decomposed<Float> Decompose(Float v) {
+ int exp;
+ Float m = std::frexp(v, &exp);
+ m = std::ldexp(m, std::numeric_limits<Float>::digits);
+ exp -= std::numeric_limits<Float>::digits;
+ return {m, exp};
+}
+
+// Print 'digits' as decimal.
+// In Fixed mode, we add a '.' at the end.
+// In Precision mode, we add a '.' after the first digit.
+template <FormatStyle mode, typename Int>
+int PrintIntegralDigits(Int digits, Buffer *out) {
+ int printed = 0;
+ if (digits) {
+ for (; digits; digits /= 10) out->push_front(digits % 10 + '0');
+ printed = out->size();
+ if (mode == FormatStyle::Precision) {
+ out->push_front(*out->begin);
+ out->begin[1] = '.';
+ } else {
+ out->push_back('.');
+ }
+ } else if (mode == FormatStyle::Fixed) {
+ out->push_front('0');
+ out->push_back('.');
+ printed = 1;
+ }
+ return printed;
+}
+
+// Back out 'extra_digits' digits and round up if necessary.
+bool RemoveExtraPrecision(int extra_digits, bool has_leftover_value,
+ Buffer *out, int *exp_out) {
+ if (extra_digits <= 0) return false;
+
+ // Back out the extra digits
+ out->end -= extra_digits;
+
+ bool needs_to_round_up = [&] {
+ // We look at the digit just past the end.
+ // There must be 'extra_digits' extra valid digits after end.
+ if (*out->end > '5') return true;
+ if (*out->end < '5') return false;
+ if (has_leftover_value || std::any_of(out->end + 1, out->end + extra_digits,
+ [](char c) { return c != '0'; }))
+ return true;
+
+ // Ends in ...50*, round to even.
+ return out->last_digit() % 2 == 1;
+ }();
+
+ if (needs_to_round_up) {
+ RoundUp<FormatStyle::Precision>(out, exp_out);
+ }
+ return true;
+}
+
+// Print the value into the buffer.
+// This will not include the exponent, which will be returned in 'exp_out' for
+// Precision mode.
+template <typename Int, typename Float, FormatStyle mode>
+bool FloatToBufferImpl(Int int_mantissa, int exp, int precision, Buffer *out,
+ int *exp_out) {
+ assert((CanFitMantissa<Float, Int>()));
+
+ const int int_bits = std::numeric_limits<Int>::digits;
+
+ // In precision mode, we start printing one char to the right because it will
+ // also include the '.'
+ // In fixed mode we put the dot afterwards on the right.
+ out->begin = out->end =
+ out->data + 1 + kMaxFixedPrecision + (mode == FormatStyle::Precision);
+
+ if (exp >= 0) {
+ if (std::numeric_limits<Float>::digits + exp > int_bits) {
+ // The value will overflow the Int
+ return false;
+ }
+ int digits_printed = PrintIntegralDigits<mode>(int_mantissa << exp, out);
+ int digits_to_zero_pad = precision;
+ if (mode == FormatStyle::Precision) {
+ *exp_out = digits_printed - 1;
+ digits_to_zero_pad -= digits_printed - 1;
+ if (RemoveExtraPrecision(-digits_to_zero_pad, false, out, exp_out)) {
+ return true;
+ }
+ }
+ for (; digits_to_zero_pad-- > 0;) out->push_back('0');
+ return true;
+ }
+
+ exp = -exp;
+ // We need at least 4 empty bits for the next decimal digit.
+ // We will multiply by 10.
+ if (exp > int_bits - 4) return false;
+
+ const Int mask = (Int{1} << exp) - 1;
+
+ // Print the integral part first.
+ int digits_printed = PrintIntegralDigits<mode>(int_mantissa >> exp, out);
+ int_mantissa &= mask;
+
+ int fractional_count = precision;
+ if (mode == FormatStyle::Precision) {
+ if (digits_printed == 0) {
+ // Find the first non-zero digit, when in Precision mode.
+ *exp_out = 0;
+ if (int_mantissa) {
+ while (int_mantissa <= mask) {
+ int_mantissa *= 10;
+ --*exp_out;
+ }
+ }
+ out->push_front(static_cast<char>(int_mantissa >> exp) + '0');
+ out->push_back('.');
+ int_mantissa &= mask;
+ } else {
+ // We already have a digit, and a '.'
+ *exp_out = digits_printed - 1;
+ fractional_count -= *exp_out;
+ if (RemoveExtraPrecision(-fractional_count, int_mantissa != 0, out,
+ exp_out)) {
+ // If we had enough digits, return right away.
+ // The code below will try to round again otherwise.
+ return true;
+ }
+ }
+ }
+
+ auto get_next_digit = [&] {
+ int_mantissa *= 10;
+ int digit = static_cast<int>(int_mantissa >> exp);
+ int_mantissa &= mask;
+ return digit;
+ };
+
+ // Print fractional_count more digits, if available.
+ for (; fractional_count > 0; --fractional_count) {
+ out->push_back(get_next_digit() + '0');
+ }
+
+ int next_digit = get_next_digit();
+ if (next_digit > 5 ||
+ (next_digit == 5 && (int_mantissa || out->last_digit() % 2 == 1))) {
+ RoundUp<mode>(out, exp_out);
+ }
+
+ return true;
+}
+
+template <FormatStyle mode, typename Float>
+bool FloatToBuffer(Decomposed<Float> decomposed, int precision, Buffer *out,
+ int *exp) {
+ if (precision > kMaxFixedPrecision) return false;
+
+ // Try with uint64_t.
+ if (CanFitMantissa<Float, std::uint64_t>() &&
+ FloatToBufferImpl<std::uint64_t, Float, mode>(
+ static_cast<std::uint64_t>(decomposed.mantissa),
+ static_cast<std::uint64_t>(decomposed.exponent), precision, out, exp))
+ return true;
+
+#if defined(__SIZEOF_INT128__)
+ // If that is not enough, try with __uint128_t.
+ return CanFitMantissa<Float, __uint128_t>() &&
+ FloatToBufferImpl<__uint128_t, Float, mode>(
+ static_cast<__uint128_t>(decomposed.mantissa),
+ static_cast<__uint128_t>(decomposed.exponent), precision, out,
+ exp);
+#endif
+ return false;
+}
+
+void WriteBufferToSink(char sign_char, string_view str,
+ const ConversionSpec &conv, FormatSinkImpl *sink) {
+ int left_spaces = 0, zeros = 0, right_spaces = 0;
+ int missing_chars =
+ conv.width() >= 0 ? std::max(conv.width() - static_cast<int>(str.size()) -
+ static_cast<int>(sign_char != 0),
+ 0)
+ : 0;
+ if (conv.flags().left) {
+ right_spaces = missing_chars;
+ } else if (conv.flags().zero) {
+ zeros = missing_chars;
+ } else {
+ left_spaces = missing_chars;
+ }
+
+ sink->Append(left_spaces, ' ');
+ if (sign_char) sink->Append(1, sign_char);
+ sink->Append(zeros, '0');
+ sink->Append(str);
+ sink->Append(right_spaces, ' ');
+}
+
+template <typename Float>
+bool FloatToSink(const Float v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ // Print the sign or the sign column.
+ Float abs_v = v;
+ char sign_char = 0;
+ if (std::signbit(abs_v)) {
+ sign_char = '-';
+ abs_v = -abs_v;
+ } else if (conv.flags().show_pos) {
+ sign_char = '+';
+ } else if (conv.flags().sign_col) {
+ sign_char = ' ';
+ }
+
+ // Print nan/inf.
+ if (ConvertNonNumericFloats(sign_char, abs_v, conv, sink)) {
+ return true;
+ }
+
+ int precision = conv.precision() < 0 ? 6 : conv.precision();
+
+ int exp = 0;
+
+ auto decomposed = Decompose(abs_v);
+
+ Buffer buffer;
+
+ switch (conv.conv().id()) {
+ case ConversionChar::f:
+ case ConversionChar::F:
+ if (!FloatToBuffer<FormatStyle::Fixed>(decomposed, precision, &buffer,
+ nullptr)) {
+ return FallbackToSnprintf(v, conv, sink);
+ }
+ if (!conv.flags().alt && buffer.back() == '.') buffer.pop_back();
+ break;
+
+ case ConversionChar::e:
+ case ConversionChar::E:
+ if (!FloatToBuffer<FormatStyle::Precision>(decomposed, precision, &buffer,
+ &exp)) {
+ return FallbackToSnprintf(v, conv, sink);
+ }
+ if (!conv.flags().alt && buffer.back() == '.') buffer.pop_back();
+ PrintExponent(exp, conv.conv().upper() ? 'E' : 'e', &buffer);
+ break;
+
+ case ConversionChar::g:
+ case ConversionChar::G:
+ precision = std::max(0, precision - 1);
+ if (!FloatToBuffer<FormatStyle::Precision>(decomposed, precision, &buffer,
+ &exp)) {
+ return FallbackToSnprintf(v, conv, sink);
+ }
+ if (precision + 1 > exp && exp >= -4) {
+ if (exp < 0) {
+ // Have 1.23456, needs 0.00123456
+ // Move the first digit
+ buffer.begin[1] = *buffer.begin;
+ // Add some zeros
+ for (; exp < -1; ++exp) *buffer.begin-- = '0';
+ *buffer.begin-- = '.';
+ *buffer.begin = '0';
+ } else if (exp > 0) {
+ // Have 1.23456, needs 1234.56
+ // Move the '.' exp positions to the right.
+ std::rotate(buffer.begin + 1, buffer.begin + 2,
+ buffer.begin + exp + 2);
+ }
+ exp = 0;
+ }
+ if (!conv.flags().alt) {
+ while (buffer.back() == '0') buffer.pop_back();
+ if (buffer.back() == '.') buffer.pop_back();
+ }
+ if (exp) PrintExponent(exp, conv.conv().upper() ? 'E' : 'e', &buffer);
+ break;
+
+ case ConversionChar::a:
+ case ConversionChar::A:
+ return FallbackToSnprintf(v, conv, sink);
+
+ default:
+ return false;
+ }
+
+ WriteBufferToSink(sign_char,
+ string_view(buffer.begin, buffer.end - buffer.begin), conv,
+ sink);
+
+ return true;
+}
+
+} // namespace
+
+bool ConvertFloatImpl(long double v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return FloatToSink(v, conv, sink);
+}
+
+bool ConvertFloatImpl(float v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return FloatToSink(v, conv, sink);
+}
+
+bool ConvertFloatImpl(double v, const ConversionSpec &conv,
+ FormatSinkImpl *sink) {
+ return FloatToSink(v, conv, sink);
+}
+
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/float_conversion.h b/absl/strings/internal/str_format/float_conversion.h
new file mode 100644
index 00000000..8ba5566d
--- /dev/null
+++ b/absl/strings/internal/str_format/float_conversion.h
@@ -0,0 +1,21 @@
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_FLOAT_CONVERSION_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_FLOAT_CONVERSION_H_
+
+#include "absl/strings/internal/str_format/extension.h"
+
+namespace absl {
+namespace str_format_internal {
+
+bool ConvertFloatImpl(float v, const ConversionSpec &conv,
+ FormatSinkImpl *sink);
+
+bool ConvertFloatImpl(double v, const ConversionSpec &conv,
+ FormatSinkImpl *sink);
+
+bool ConvertFloatImpl(long double v, const ConversionSpec &conv,
+ FormatSinkImpl *sink);
+
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_FLOAT_CONVERSION_H_
diff --git a/absl/strings/internal/str_format/output.cc b/absl/strings/internal/str_format/output.cc
new file mode 100644
index 00000000..5c3795b7
--- /dev/null
+++ b/absl/strings/internal/str_format/output.cc
@@ -0,0 +1,47 @@
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/strings/internal/str_format/output.h"
+
+#include <errno.h>
+#include <cstring>
+
+namespace absl {
+namespace str_format_internal {
+
+void BufferRawSink::Write(string_view v) {
+ size_t to_write = std::min(v.size(), size_);
+ std::memcpy(buffer_, v.data(), to_write);
+ buffer_ += to_write;
+ size_ -= to_write;
+ total_written_ += v.size();
+}
+
+void FILERawSink::Write(string_view v) {
+ while (!v.empty() && !error_) {
+ if (size_t result = std::fwrite(v.data(), 1, v.size(), output_)) {
+ // Some progress was made.
+ count_ += result;
+ v.remove_prefix(result);
+ } else {
+ // Some error occurred.
+ if (errno != EINTR) {
+ error_ = errno;
+ }
+ }
+ }
+}
+
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/output.h b/absl/strings/internal/str_format/output.h
new file mode 100644
index 00000000..3b0aa5e7
--- /dev/null
+++ b/absl/strings/internal/str_format/output.h
@@ -0,0 +1,101 @@
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Output extension hooks for the Format library.
+// `internal::InvokeFlush` calls the appropriate flush function for the
+// specified output argument.
+// `BufferRawSink` is a simple output sink for a char buffer. Used by SnprintF.
+// `FILERawSink` is a std::FILE* based sink. Used by PrintF and FprintF.
+
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_OUTPUT_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_OUTPUT_H_
+
+#include <cstdio>
+#include <ostream>
+#include <string>
+
+#include "absl/base/port.h"
+#include "absl/strings/string_view.h"
+
+class Cord;
+
+namespace absl {
+namespace str_format_internal {
+
+// RawSink implementation that writes into a char* buffer.
+// It will not overflow the buffer, but will keep the total count of chars
+// that would have been written.
+class BufferRawSink {
+ public:
+ BufferRawSink(char* buffer, size_t size) : buffer_(buffer), size_(size) {}
+
+ size_t total_written() const { return total_written_; }
+ void Write(string_view v);
+
+ private:
+ char* buffer_;
+ size_t size_;
+ size_t total_written_ = 0;
+};
+
+// RawSink implementation that writes into a FILE*.
+// It keeps track of the total number of bytes written and any error encountered
+// during the writes.
+class FILERawSink {
+ public:
+ explicit FILERawSink(std::FILE* output) : output_(output) {}
+
+ void Write(string_view v);
+
+ size_t count() const { return count_; }
+ int error() const { return error_; }
+
+ private:
+ std::FILE* output_;
+ int error_ = 0;
+ size_t count_ = 0;
+};
+
+// Provide RawSink integration with common types from the STL.
+inline void AbslFormatFlush(std::string* out, string_view s) {
+ out->append(s.begin(), s.size());
+}
+inline void AbslFormatFlush(std::ostream* out, string_view s) {
+ out->write(s.begin(), s.size());
+}
+
+template <class AbslCord, typename = typename std::enable_if<
+ std::is_same<AbslCord, ::Cord>::value>::type>
+inline void AbslFormatFlush(AbslCord* out, string_view s) {
+ out->Append(s);
+}
+
+inline void AbslFormatFlush(FILERawSink* sink, string_view v) {
+ sink->Write(v);
+}
+
+inline void AbslFormatFlush(BufferRawSink* sink, string_view v) {
+ sink->Write(v);
+}
+
+template <typename T>
+auto InvokeFlush(T* out, string_view s)
+ -> decltype(str_format_internal::AbslFormatFlush(out, s)) {
+ str_format_internal::AbslFormatFlush(out, s);
+}
+
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_OUTPUT_H_
diff --git a/absl/strings/internal/str_format/output_test.cc b/absl/strings/internal/str_format/output_test.cc
new file mode 100644
index 00000000..cc3c6155
--- /dev/null
+++ b/absl/strings/internal/str_format/output_test.cc
@@ -0,0 +1,78 @@
+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/strings/internal/str_format/output.h"
+
+#include <sstream>
+#include <string>
+
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace absl {
+namespace {
+
+TEST(InvokeFlush, String) {
+ std::string str = "ABC";
+ str_format_internal::InvokeFlush(&str, "DEF");
+ EXPECT_EQ(str, "ABCDEF");
+
+#if UTIL_FORMAT_HAS_GLOBAL_STRING
+ std::string str2 = "ABC";
+ str_format_internal::InvokeFlush(&str2, "DEF");
+ EXPECT_EQ(str2, "ABCDEF");
+#endif // UTIL_FORMAT_HAS_GLOBAL_STRING
+}
+
+TEST(InvokeFlush, Stream) {
+ std::stringstream str;
+ str << "ABC";
+ str_format_internal::InvokeFlush(&str, "DEF");
+ EXPECT_EQ(str.str(), "ABCDEF");
+}
+
+TEST(BufferRawSink, Limits) {
+ char buf[16];
+ {
+ std::fill(std::begin(buf), std::end(buf), 'x');
+ str_format_internal::BufferRawSink bufsink(buf, sizeof(buf) - 1);
+ str_format_internal::InvokeFlush(&bufsink, "Hello World237");
+ EXPECT_EQ(std::string(buf, sizeof(buf)), "Hello World237xx");
+ }
+ {
+ std::fill(std::begin(buf), std::end(buf), 'x');
+ str_format_internal::BufferRawSink bufsink(buf, sizeof(buf) - 1);
+ str_format_internal::InvokeFlush(&bufsink, "Hello World237237");
+ EXPECT_EQ(std::string(buf, sizeof(buf)), "Hello World2372x");
+ }
+ {
+ std::fill(std::begin(buf), std::end(buf), 'x');
+ str_format_internal::BufferRawSink bufsink(buf, sizeof(buf) - 1);
+ str_format_internal::InvokeFlush(&bufsink, "Hello World");
+ str_format_internal::InvokeFlush(&bufsink, "237");
+ EXPECT_EQ(std::string(buf, sizeof(buf)), "Hello World237xx");
+ }
+ {
+ std::fill(std::begin(buf), std::end(buf), 'x');
+ str_format_internal::BufferRawSink bufsink(buf, sizeof(buf) - 1);
+ str_format_internal::InvokeFlush(&bufsink, "Hello World");
+ str_format_internal::InvokeFlush(&bufsink, "237237");
+ EXPECT_EQ(std::string(buf, sizeof(buf)), "Hello World2372x");
+ }
+}
+
+} // namespace
+} // namespace absl
+
diff --git a/absl/strings/internal/str_format/parser.cc b/absl/strings/internal/str_format/parser.cc
new file mode 100644
index 00000000..10114f48
--- /dev/null
+++ b/absl/strings/internal/str_format/parser.cc
@@ -0,0 +1,294 @@
+#include "absl/strings/internal/str_format/parser.h"
+
+#include <assert.h>
+#include <string.h>
+#include <wchar.h>
+#include <cctype>
+#include <cstdint>
+
+#include <algorithm>
+#include <initializer_list>
+#include <limits>
+#include <ostream>
+#include <string>
+#include <unordered_set>
+
+namespace absl {
+namespace str_format_internal {
+namespace {
+
+bool CheckFastPathSetting(const UnboundConversion& conv) {
+ bool should_be_basic = !conv.flags.left && //
+ !conv.flags.show_pos && //
+ !conv.flags.sign_col && //
+ !conv.flags.alt && //
+ !conv.flags.zero && //
+ (conv.width.value() == -1) &&
+ (conv.precision.value() == -1);
+ if (should_be_basic != conv.flags.basic) {
+ fprintf(stderr,
+ "basic=%d left=%d show_pos=%d sign_col=%d alt=%d zero=%d "
+ "width=%d precision=%d\n",
+ conv.flags.basic, conv.flags.left, conv.flags.show_pos,
+ conv.flags.sign_col, conv.flags.alt, conv.flags.zero,
+ conv.width.value(), conv.precision.value());
+ }
+ return should_be_basic == conv.flags.basic;
+}
+
+// Keep a single table for all the conversion chars and length modifiers.
+// We invert the length modifiers to make them negative so that we can easily
+// test for them.
+// Everything else is `none`, which is a negative constant.
+using CC = ConversionChar::Id;
+using LM = LengthMod::Id;
+static constexpr std::int8_t none = -128;
+static constexpr std::int8_t kIds[] = {
+ none, none, none, none, none, none, none, none, // 00-07
+ none, none, none, none, none, none, none, none, // 08-0f
+ none, none, none, none, none, none, none, none, // 10-17
+ none, none, none, none, none, none, none, none, // 18-1f
+ none, none, none, none, none, none, none, none, // 20-27
+ none, none, none, none, none, none, none, none, // 28-2f
+ none, none, none, none, none, none, none, none, // 30-37
+ none, none, none, none, none, none, none, none, // 38-3f
+ none, CC::A, none, CC::C, none, CC::E, CC::F, CC::G, // @ABCDEFG
+ none, none, none, none, ~LM::L, none, none, none, // HIJKLMNO
+ none, none, none, CC::S, none, none, none, none, // PQRSTUVW
+ CC::X, none, none, none, none, none, none, none, // XYZ[\]^_
+ none, CC::a, none, CC::c, CC::d, CC::e, CC::f, CC::g, // `abcdefg
+ ~LM::h, CC::i, ~LM::j, none, ~LM::l, none, CC::n, CC::o, // hijklmno
+ CC::p, ~LM::q, none, CC::s, ~LM::t, CC::u, none, none, // pqrstuvw
+ CC::x, none, ~LM::z, none, none, none, none, none, // xyz{|}~!
+ none, none, none, none, none, none, none, none, // 80-87
+ none, none, none, none, none, none, none, none, // 88-8f
+ none, none, none, none, none, none, none, none, // 90-97
+ none, none, none, none, none, none, none, none, // 98-9f
+ none, none, none, none, none, none, none, none, // a0-a7
+ none, none, none, none, none, none, none, none, // a8-af
+ none, none, none, none, none, none, none, none, // b0-b7
+ none, none, none, none, none, none, none, none, // b8-bf
+ none, none, none, none, none, none, none, none, // c0-c7
+ none, none, none, none, none, none, none, none, // c8-cf
+ none, none, none, none, none, none, none, none, // d0-d7
+ none, none, none, none, none, none, none, none, // d8-df
+ none, none, none, none, none, none, none, none, // e0-e7
+ none, none, none, none, none, none, none, none, // e8-ef
+ none, none, none, none, none, none, none, none, // f0-f7
+ none, none, none, none, none, none, none, none, // f8-ff
+};
+
+template <bool is_positional>
+bool ConsumeConversion(string_view *src, UnboundConversion *conv,
+ int *next_arg) {
+ const char *pos = src->begin();
+ const char *const end = src->end();
+ char c;
+ // Read the next char into `c` and update `pos`. Reads '\0' if at end.
+ const auto get_char = [&] { c = pos == end ? '\0' : *pos++; };
+
+ const auto parse_digits = [&] {
+ int digits = c - '0';
+ // We do not want to overflow `digits` so we consume at most digits10-1
+ // digits. If there are more digits the parsing will fail later on when the
+ // digit doesn't match the expected characters.
+ int num_digits = std::numeric_limits<int>::digits10 - 2;
+ for (get_char(); num_digits && std::isdigit(c); get_char()) {
+ --num_digits;
+ digits = 10 * digits + c - '0';
+ }
+ return digits;
+ };
+
+ if (is_positional) {
+ get_char();
+ if (c < '1' || c > '9') return false;
+ conv->arg_position = parse_digits();
+ assert(conv->arg_position > 0);
+ if (c != '$') return false;
+ }
+
+ get_char();
+
+ // We should start with the basic flag on.
+ assert(conv->flags.basic);
+
+ // Any non alpha character makes this conversion not basic.
+ // This includes flags (-+ #0), width (1-9, *) or precision (.).
+ // All conversion characters and length modifiers are alpha characters.
+ if (c < 'A') {
+ conv->flags.basic = false;
+
+ for (; c <= '0'; get_char()) {
+ switch (c) {
+ case '-':
+ conv->flags.left = true;
+ continue;
+ case '+':
+ conv->flags.show_pos = true;
+ continue;
+ case ' ':
+ conv->flags.sign_col = true;
+ continue;
+ case '#':
+ conv->flags.alt = true;
+ continue;
+ case '0':
+ conv->flags.zero = true;
+ continue;
+ }
+ break;
+ }
+
+ if (c <= '9') {
+ if (c >= '0') {
+ int maybe_width = parse_digits();
+ if (!is_positional && c == '$') {
+ if (*next_arg != 0) return false;
+ // Positional conversion.
+ *next_arg = -1;
+ conv->flags = Flags();
+ conv->flags.basic = true;
+ return ConsumeConversion<true>(src, conv, next_arg);
+ }
+ conv->width.set_value(maybe_width);
+ } else if (c == '*') {
+ get_char();
+ if (is_positional) {
+ if (c < '1' || c > '9') return false;
+ conv->width.set_from_arg(parse_digits());
+ if (c != '$') return false;
+ get_char();
+ } else {
+ conv->width.set_from_arg(++*next_arg);
+ }
+ }
+ }
+
+ if (c == '.') {
+ get_char();
+ if (std::isdigit(c)) {
+ conv->precision.set_value(parse_digits());
+ } else if (c == '*') {
+ get_char();
+ if (is_positional) {
+ if (c < '1' || c > '9') return false;
+ conv->precision.set_from_arg(parse_digits());
+ if (c != '$') return false;
+ get_char();
+ } else {
+ conv->precision.set_from_arg(++*next_arg);
+ }
+ } else {
+ conv->precision.set_value(0);
+ }
+ }
+ }
+
+ std::int8_t id = kIds[static_cast<unsigned char>(c)];
+
+ if (id < 0) {
+ if (id == none) return false;
+
+ // It is a length modifier.
+ using str_format_internal::LengthMod;
+ LengthMod length_mod = LengthMod::FromId(static_cast<LM>(~id));
+ get_char();
+ if (c == 'h' && length_mod.id() == LengthMod::h) {
+ conv->length_mod = LengthMod::FromId(LengthMod::hh);
+ get_char();
+ } else if (c == 'l' && length_mod.id() == LengthMod::l) {
+ conv->length_mod = LengthMod::FromId(LengthMod::ll);
+ get_char();
+ } else {
+ conv->length_mod = length_mod;
+ }
+ id = kIds[static_cast<unsigned char>(c)];
+ if (id < 0) return false;
+ }
+
+ assert(CheckFastPathSetting(*conv));
+ (void)(&CheckFastPathSetting);
+
+ conv->conv = ConversionChar::FromId(static_cast<CC>(id));
+ if (!is_positional) conv->arg_position = ++*next_arg;
+ *src = string_view(pos, end - pos);
+ return true;
+}
+
+} // namespace
+
+bool ConsumeUnboundConversion(string_view *src, UnboundConversion *conv,
+ int *next_arg) {
+ if (*next_arg < 0) return ConsumeConversion<true>(src, conv, next_arg);
+ return ConsumeConversion<false>(src, conv, next_arg);
+}
+
+struct ParsedFormatBase::ParsedFormatConsumer {
+ explicit ParsedFormatConsumer(ParsedFormatBase *parsedformat)
+ : parsed(parsedformat), data_pos(parsedformat->data_.get()) {}
+
+ bool Append(string_view s) {
+ if (s.empty()) return true;
+
+ size_t text_end = AppendText(s);
+
+ if (!parsed->items_.empty() && !parsed->items_.back().is_conversion) {
+ // Let's extend the existing text run.
+ parsed->items_.back().text_end = text_end;
+ } else {
+ // Let's make a new text run.
+ parsed->items_.push_back({false, text_end, {}});
+ }
+ return true;
+ }
+
+ bool ConvertOne(const UnboundConversion &conv, string_view s) {
+ size_t text_end = AppendText(s);
+ parsed->items_.push_back({true, text_end, conv});
+ return true;
+ }
+
+ size_t AppendText(string_view s) {
+ memcpy(data_pos, s.data(), s.size());
+ data_pos += s.size();
+ return static_cast<size_t>(data_pos - parsed->data_.get());
+ }
+
+ ParsedFormatBase *parsed;
+ char* data_pos;
+};
+
+ParsedFormatBase::ParsedFormatBase(string_view format, bool allow_ignored,
+ std::initializer_list<Conv> convs)
+ : data_(format.empty() ? nullptr : new char[format.size()]) {
+ has_error_ = !ParseFormatString(format, ParsedFormatConsumer(this)) ||
+ !MatchesConversions(allow_ignored, convs);
+}
+
+bool ParsedFormatBase::MatchesConversions(
+ bool allow_ignored, std::initializer_list<Conv> convs) const {
+ std::unordered_set<int> used;
+ auto add_if_valid_conv = [&](int pos, char c) {
+ if (static_cast<size_t>(pos) > convs.size() ||
+ !Contains(convs.begin()[pos - 1], c))
+ return false;
+ used.insert(pos);
+ return true;
+ };
+ for (const ConversionItem &item : items_) {
+ if (!item.is_conversion) continue;
+ auto &conv = item.conv;
+ if (conv.precision.is_from_arg() &&
+ !add_if_valid_conv(conv.precision.get_from_arg(), '*'))
+ return false;
+ if (conv.width.is_from_arg() &&
+ !add_if_valid_conv(conv.width.get_from_arg(), '*'))
+ return false;
+ if (!add_if_valid_conv(conv.arg_position, conv.conv.Char())) return false;
+ }
+ return used.size() == convs.size() || allow_ignored;
+}
+
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/internal/str_format/parser.h b/absl/strings/internal/str_format/parser.h
new file mode 100644
index 00000000..5bebc955
--- /dev/null
+++ b/absl/strings/internal/str_format/parser.h
@@ -0,0 +1,291 @@
+#ifndef ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
+#define ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
+
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+#include <cassert>
+#include <initializer_list>
+#include <iosfwd>
+#include <iterator>
+#include <memory>
+#include <vector>
+
+#include "absl/strings/internal/str_format/checker.h"
+#include "absl/strings/internal/str_format/extension.h"
+
+namespace absl {
+namespace str_format_internal {
+
+// The analyzed properties of a single specified conversion.
+struct UnboundConversion {
+ UnboundConversion()
+ : flags() /* This is required to zero all the fields of flags. */ {
+ flags.basic = true;
+ }
+
+ class InputValue {
+ public:
+ void set_value(int value) {
+ assert(value >= 0);
+ value_ = value;
+ }
+ int value() const { return value_; }
+
+ // Marks the value as "from arg". aka the '*' format.
+ // Requires `value >= 1`.
+ // When set, is_from_arg() return true and get_from_arg() returns the
+ // original value.
+ // `value()`'s return value is unspecfied in this state.
+ void set_from_arg(int value) {
+ assert(value > 0);
+ value_ = -value - 1;
+ }
+ bool is_from_arg() const { return value_ < -1; }
+ int get_from_arg() const {
+ assert(is_from_arg());
+ return -value_ - 1;
+ }
+
+ private:
+ int value_ = -1;
+ };
+
+ // No need to initialize. It will always be set in the parser.
+ int arg_position;
+
+ InputValue width;
+ InputValue precision;
+
+ Flags flags;
+ LengthMod length_mod;
+ ConversionChar conv;
+};
+
+// Consume conversion spec prefix (not including '%') of '*src' if valid.
+// Examples of valid specs would be e.g.: "s", "d", "-12.6f".
+// If valid, the front of src is advanced such that src becomes the
+// part following the conversion spec, and the spec part is broken down and
+// returned in 'conv'.
+// If invalid, returns false and leaves 'src' unmodified.
+// For example:
+// Given "d9", returns "d", and leaves src="9",
+// Given "!", returns "" and leaves src="!".
+bool ConsumeUnboundConversion(string_view* src, UnboundConversion* conv,
+ int* next_arg);
+
+// Parse the format std::string provided in 'src' and pass the identified items into
+// 'consumer'.
+// Text runs will be passed by calling
+// Consumer::Append(string_view);
+// ConversionItems will be passed by calling
+// Consumer::ConvertOne(UnboundConversion, string_view);
+// In the case of ConvertOne, the string_view that is passed is the
+// portion of the format std::string corresponding to the conversion, not including
+// the leading %. On success, it returns true. On failure, it stops and returns
+// false.
+template <typename Consumer>
+bool ParseFormatString(string_view src, Consumer consumer) {
+ int next_arg = 0;
+ while (!src.empty()) {
+ const char* percent =
+ static_cast<const char*>(memchr(src.begin(), '%', src.size()));
+ if (!percent) {
+ // We found the last substring.
+ return consumer.Append(src);
+ }
+ // We found a percent, so push the text run then process the percent.
+ size_t percent_loc = percent - src.data();
+ if (!consumer.Append(string_view(src.data(), percent_loc))) return false;
+ if (percent + 1 >= src.end()) return false;
+
+ UnboundConversion conv;
+
+ switch (percent[1]) {
+ case '%':
+ if (!consumer.Append("%")) return false;
+ src.remove_prefix(percent_loc + 2);
+ continue;
+
+#define PARSER_CASE(ch) \
+ case #ch[0]: \
+ src.remove_prefix(percent_loc + 2); \
+ conv.conv = ConversionChar::FromId(ConversionChar::ch); \
+ conv.arg_position = ++next_arg; \
+ break;
+ ABSL_CONVERSION_CHARS_EXPAND_(PARSER_CASE, );
+#undef PARSER_CASE
+
+ default:
+ src.remove_prefix(percent_loc + 1);
+ if (!ConsumeUnboundConversion(&src, &conv, &next_arg)) return false;
+ break;
+ }
+ if (next_arg == 0) {
+ // This indicates an error in the format std::string.
+ // The only way to get next_arg == 0 is to have a positional argument
+ // first which sets next_arg to -1 and then a non-positional argument
+ // which does ++next_arg.
+ // Checking here seems to be the cheapeast place to do it.
+ return false;
+ }
+ if (!consumer.ConvertOne(
+ conv, string_view(percent + 1, src.data() - (percent + 1)))) {
+ return false;
+ }
+ }
+ return true;
+}
+
+// Always returns true, or fails to compile in a constexpr context if s does not
+// point to a constexpr char array.
+constexpr bool EnsureConstexpr(string_view s) {
+ return s.empty() || s[0] == s[0];
+}
+
+class ParsedFormatBase {
+ public:
+ explicit ParsedFormatBase(string_view format, bool allow_ignored,
+ std::initializer_list<Conv> convs);
+
+ ParsedFormatBase(const ParsedFormatBase& other) { *this = other; }
+
+ ParsedFormatBase(ParsedFormatBase&& other) { *this = std::move(other); }
+
+ ParsedFormatBase& operator=(const ParsedFormatBase& other) {
+ if (this == &other) return *this;
+ has_error_ = other.has_error_;
+ items_ = other.items_;
+ size_t text_size = items_.empty() ? 0 : items_.back().text_end;
+ data_.reset(new char[text_size]);
+ memcpy(data_.get(), other.data_.get(), text_size);
+ return *this;
+ }
+
+ ParsedFormatBase& operator=(ParsedFormatBase&& other) {
+ if (this == &other) return *this;
+ has_error_ = other.has_error_;
+ data_ = std::move(other.data_);
+ items_ = std::move(other.items_);
+ // Reset the vector to make sure the invariants hold.
+ other.items_.clear();
+ return *this;
+ }
+
+ template <typename Consumer>
+ bool ProcessFormat(Consumer consumer) const {
+ const char* const base = data_.get();
+ string_view text(base, 0);
+ for (const auto& item : items_) {
+ text = string_view(text.end(), (base + item.text_end) - text.end());
+ if (item.is_conversion) {
+ if (!consumer.ConvertOne(item.conv, text)) return false;
+ } else {
+ if (!consumer.Append(text)) return false;
+ }
+ }
+ return !has_error_;
+ }
+
+ bool has_error() const { return has_error_; }
+
+ private:
+ // Returns whether the conversions match and if !allow_ignored it verifies
+ // that all conversions are used by the format.
+ bool MatchesConversions(bool allow_ignored,
+ std::initializer_list<Conv> convs) const;
+
+ struct ParsedFormatConsumer;
+
+ struct ConversionItem {
+ bool is_conversion;
+ // Points to the past-the-end location of this element in the data_ array.
+ size_t text_end;
+ UnboundConversion conv;
+ };
+
+ bool has_error_;
+ std::unique_ptr<char[]> data_;
+ std::vector<ConversionItem> items_;
+};
+
+
+// A value type representing a preparsed format. These can be created, copied
+// around, and reused to speed up formatting loops.
+// The user must specify through the template arguments the conversion
+// characters used in the format. This will be checked at compile time.
+//
+// This class uses Conv enum values to specify each argument.
+// This allows for more flexibility as you can specify multiple possible
+// conversion characters for each argument.
+// ParsedFormat<char...> is a simplified alias for when the user only
+// needs to specify a single conversion character for each argument.
+//
+// Example:
+// // Extended format supports multiple characters per argument:
+// using MyFormat = ExtendedParsedFormat<Conv::d | Conv::x>;
+// MyFormat GetFormat(bool use_hex) {
+// if (use_hex) return MyFormat("foo %x bar");
+// return MyFormat("foo %d bar");
+// }
+// // 'format' can be used with any value that supports 'd' and 'x',
+// // like `int`.
+// auto format = GetFormat(use_hex);
+// value = StringF(format, i);
+//
+// This class also supports runtime format checking with the ::New() and
+// ::NewAllowIgnored() factory functions.
+// This is the only API that allows the user to pass a runtime specified format
+// std::string. These factory functions will return NULL if the format does not match
+// the conversions requested by the user.
+template <str_format_internal::Conv... C>
+class ExtendedParsedFormat : public str_format_internal::ParsedFormatBase {
+ public:
+ explicit ExtendedParsedFormat(string_view format)
+#if ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+ __attribute__((
+ enable_if(str_format_internal::EnsureConstexpr(format),
+ "Format std::string is not constexpr."),
+ enable_if(str_format_internal::ValidFormatImpl<C...>(format),
+ "Format specified does not match the template arguments.")))
+#endif // ABSL_INTERNAL_ENABLE_FORMAT_CHECKER
+ : ExtendedParsedFormat(format, false) {
+ }
+
+ // ExtendedParsedFormat factory function.
+ // The user still has to specify the conversion characters, but they will not
+ // be checked at compile time. Instead, it will be checked at runtime.
+ // This delays the checking to runtime, but allows the user to pass
+ // dynamically sourced formats.
+ // It returns NULL if the format does not match the conversion characters.
+ // The user is responsible for checking the return value before using it.
+ //
+ // The 'New' variant will check that all the specified arguments are being
+ // consumed by the format and return NULL if any argument is being ignored.
+ // The 'NewAllowIgnored' variant will not verify this and will allow formats
+ // that ignore arguments.
+ static std::unique_ptr<ExtendedParsedFormat> New(string_view format) {
+ return New(format, false);
+ }
+ static std::unique_ptr<ExtendedParsedFormat> NewAllowIgnored(
+ string_view format) {
+ return New(format, true);
+ }
+
+ private:
+ static std::unique_ptr<ExtendedParsedFormat> New(string_view format,
+ bool allow_ignored) {
+ std::unique_ptr<ExtendedParsedFormat> conv(
+ new ExtendedParsedFormat(format, allow_ignored));
+ if (conv->has_error()) return nullptr;
+ return conv;
+ }
+
+ ExtendedParsedFormat(string_view s, bool allow_ignored)
+ : ParsedFormatBase(s, allow_ignored, {C...}) {}
+};
+} // namespace str_format_internal
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_STR_FORMAT_PARSER_H_
diff --git a/absl/strings/internal/str_format/parser_test.cc b/absl/strings/internal/str_format/parser_test.cc
new file mode 100644
index 00000000..e698020b
--- /dev/null
+++ b/absl/strings/internal/str_format/parser_test.cc
@@ -0,0 +1,379 @@
+#include "absl/strings/internal/str_format/parser.h"
+
+#include <string.h>
+#include "gtest/gtest.h"
+#include "absl/base/macros.h"
+
+namespace absl {
+namespace str_format_internal {
+
+namespace {
+
+TEST(LengthModTest, Names) {
+ struct Expectation {
+ int line;
+ LengthMod::Id id;
+ const char *name;
+ };
+ const Expectation kExpect[] = {
+ {__LINE__, LengthMod::none, "" },
+ {__LINE__, LengthMod::h, "h" },
+ {__LINE__, LengthMod::hh, "hh"},
+ {__LINE__, LengthMod::l, "l" },
+ {__LINE__, LengthMod::ll, "ll"},
+ {__LINE__, LengthMod::L, "L" },
+ {__LINE__, LengthMod::j, "j" },
+ {__LINE__, LengthMod::z, "z" },
+ {__LINE__, LengthMod::t, "t" },
+ {__LINE__, LengthMod::q, "q" },
+ };
+ EXPECT_EQ(ABSL_ARRAYSIZE(kExpect), LengthMod::kNumValues);
+ for (auto e : kExpect) {
+ SCOPED_TRACE(e.line);
+ LengthMod mod = LengthMod::FromId(e.id);
+ EXPECT_EQ(e.id, mod.id());
+ EXPECT_EQ(e.name, mod.name());
+ }
+}
+
+TEST(ConversionCharTest, Names) {
+ struct Expectation {
+ ConversionChar::Id id;
+ char name;
+ };
+ // clang-format off
+ const Expectation kExpect[] = {
+#define X(c) {ConversionChar::c, #c[0]}
+ X(c), X(C), X(s), X(S), // text
+ X(d), X(i), X(o), X(u), X(x), X(X), // int
+ X(f), X(F), X(e), X(E), X(g), X(G), X(a), X(A), // float
+ X(n), X(p), // misc
+#undef X
+ {ConversionChar::none, '\0'},
+ };
+ // clang-format on
+ EXPECT_EQ(ABSL_ARRAYSIZE(kExpect), ConversionChar::kNumValues);
+ for (auto e : kExpect) {
+ SCOPED_TRACE(e.name);
+ ConversionChar v = ConversionChar::FromId(e.id);
+ EXPECT_EQ(e.id, v.id());
+ EXPECT_EQ(e.name, v.Char());
+ }
+}
+
+class ConsumeUnboundConversionTest : public ::testing::Test {
+ public:
+ typedef UnboundConversion Props;
+ string_view Consume(string_view* src) {
+ int next = 0;
+ const char* prev_begin = src->begin();
+ o = UnboundConversion(); // refresh
+ ConsumeUnboundConversion(src, &o, &next);
+ return {prev_begin, static_cast<size_t>(src->begin() - prev_begin)};
+ }
+
+ bool Run(const char *fmt, bool force_positional = false) {
+ string_view src = fmt;
+ int next = force_positional ? -1 : 0;
+ o = UnboundConversion(); // refresh
+ return ConsumeUnboundConversion(&src, &o, &next) && src.empty();
+ }
+ UnboundConversion o;
+};
+
+TEST_F(ConsumeUnboundConversionTest, ConsumeSpecification) {
+ struct Expectation {
+ int line;
+ const char *src;
+ const char *out;
+ const char *src_post;
+ };
+ const Expectation kExpect[] = {
+ {__LINE__, "", "", "" },
+ {__LINE__, "b", "", "b" }, // 'b' is invalid
+ {__LINE__, "ba", "", "ba"}, // 'b' is invalid
+ {__LINE__, "l", "", "l" }, // just length mod isn't okay
+ {__LINE__, "d", "d", "" }, // basic
+ {__LINE__, "d ", "d", " " }, // leave suffix
+ {__LINE__, "dd", "d", "d" }, // don't be greedy
+ {__LINE__, "d9", "d", "9" }, // leave non-space suffix
+ {__LINE__, "dzz", "d", "zz"}, // length mod as suffix
+ {__LINE__, "1$*2$d", "1$*2$d", "" }, // arg indexing and * allowed.
+ {__LINE__, "0-14.3hhd", "0-14.3hhd", ""}, // precision, width
+ {__LINE__, " 0-+#14.3hhd", " 0-+#14.3hhd", ""}, // flags
+ };
+ for (const auto& e : kExpect) {
+ SCOPED_TRACE(e.line);
+ string_view src = e.src;
+ EXPECT_EQ(e.src, src);
+ string_view out = Consume(&src);
+ EXPECT_EQ(e.out, out);
+ EXPECT_EQ(e.src_post, src);
+ }
+}
+
+TEST_F(ConsumeUnboundConversionTest, BasicConversion) {
+ EXPECT_FALSE(Run(""));
+ EXPECT_FALSE(Run("z"));
+
+ EXPECT_FALSE(Run("dd")); // no excess allowed
+
+ EXPECT_TRUE(Run("d"));
+ EXPECT_EQ('d', o.conv.Char());
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_LT(o.width.value(), 0);
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_LT(o.precision.value(), 0);
+ EXPECT_EQ(1, o.arg_position);
+ EXPECT_EQ(LengthMod::none, o.length_mod.id());
+}
+
+TEST_F(ConsumeUnboundConversionTest, ArgPosition) {
+ EXPECT_TRUE(Run("d"));
+ EXPECT_EQ(1, o.arg_position);
+ EXPECT_TRUE(Run("3$d"));
+ EXPECT_EQ(3, o.arg_position);
+ EXPECT_TRUE(Run("1$d"));
+ EXPECT_EQ(1, o.arg_position);
+ EXPECT_TRUE(Run("1$d", true));
+ EXPECT_EQ(1, o.arg_position);
+ EXPECT_TRUE(Run("123$d"));
+ EXPECT_EQ(123, o.arg_position);
+ EXPECT_TRUE(Run("123$d", true));
+ EXPECT_EQ(123, o.arg_position);
+ EXPECT_TRUE(Run("10$d"));
+ EXPECT_EQ(10, o.arg_position);
+ EXPECT_TRUE(Run("10$d", true));
+ EXPECT_EQ(10, o.arg_position);
+
+ // Position can't be zero.
+ EXPECT_FALSE(Run("0$d"));
+ EXPECT_FALSE(Run("0$d", true));
+ EXPECT_FALSE(Run("1$*0$d"));
+ EXPECT_FALSE(Run("1$.*0$d"));
+
+ // Position can't start with a zero digit at all. That is not a 'decimal'.
+ EXPECT_FALSE(Run("01$p"));
+ EXPECT_FALSE(Run("01$p", true));
+ EXPECT_FALSE(Run("1$*01$p"));
+ EXPECT_FALSE(Run("1$.*01$p"));
+}
+
+TEST_F(ConsumeUnboundConversionTest, WidthAndPrecision) {
+ EXPECT_TRUE(Run("14d"));
+ EXPECT_EQ('d', o.conv.Char());
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_EQ(14, o.width.value());
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_LT(o.precision.value(), 0);
+
+ EXPECT_TRUE(Run("14.d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_EQ(14, o.width.value());
+ EXPECT_EQ(0, o.precision.value());
+
+ EXPECT_TRUE(Run(".d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_LT(o.width.value(), 0);
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_EQ(0, o.precision.value());
+
+ EXPECT_TRUE(Run(".5d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_LT(o.width.value(), 0);
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_EQ(5, o.precision.value());
+
+ EXPECT_TRUE(Run(".0d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_LT(o.width.value(), 0);
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_EQ(0, o.precision.value());
+
+ EXPECT_TRUE(Run("14.5d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_EQ(14, o.width.value());
+ EXPECT_EQ(5, o.precision.value());
+
+ EXPECT_TRUE(Run("*.*d"));
+ EXPECT_TRUE(o.width.is_from_arg());
+ EXPECT_EQ(1, o.width.get_from_arg());
+ EXPECT_TRUE(o.precision.is_from_arg());
+ EXPECT_EQ(2, o.precision.get_from_arg());
+ EXPECT_EQ(3, o.arg_position);
+
+ EXPECT_TRUE(Run("*d"));
+ EXPECT_TRUE(o.width.is_from_arg());
+ EXPECT_EQ(1, o.width.get_from_arg());
+ EXPECT_FALSE(o.precision.is_from_arg());
+ EXPECT_LT(o.precision.value(), 0);
+ EXPECT_EQ(2, o.arg_position);
+
+ EXPECT_TRUE(Run(".*d"));
+ EXPECT_FALSE(o.width.is_from_arg());
+ EXPECT_LT(o.width.value(), 0);
+ EXPECT_TRUE(o.precision.is_from_arg());
+ EXPECT_EQ(1, o.precision.get_from_arg());
+ EXPECT_EQ(2, o.arg_position);
+
+ // mixed implicit and explicit: didn't specify arg position.
+ EXPECT_FALSE(Run("*23$.*34$d"));
+
+ EXPECT_TRUE(Run("12$*23$.*34$d"));
+ EXPECT_EQ(12, o.arg_position);
+ EXPECT_TRUE(o.width.is_from_arg());
+ EXPECT_EQ(23, o.width.get_from_arg());
+ EXPECT_TRUE(o.precision.is_from_arg());
+ EXPECT_EQ(34, o.precision.get_from_arg());
+
+ EXPECT_TRUE(Run("2$*5$.*9$d"));
+ EXPECT_EQ(2, o.arg_position);
+ EXPECT_TRUE(o.width.is_from_arg());
+ EXPECT_EQ(5, o.width.get_from_arg());
+ EXPECT_TRUE(o.precision.is_from_arg());
+ EXPECT_EQ(9, o.precision.get_from_arg());
+
+ EXPECT_FALSE(Run(".*0$d")) << "no arg 0";
+}
+
+TEST_F(ConsumeUnboundConversionTest, Flags) {
+ static const char kAllFlags[] = "-+ #0";
+ static const int kNumFlags = ABSL_ARRAYSIZE(kAllFlags) - 1;
+ for (int rev = 0; rev < 2; ++rev) {
+ for (int i = 0; i < 1 << kNumFlags; ++i) {
+ std::string fmt;
+ for (int k = 0; k < kNumFlags; ++k)
+ if ((i >> k) & 1) fmt += kAllFlags[k];
+ // flag order shouldn't matter
+ if (rev == 1) { std::reverse(fmt.begin(), fmt.end()); }
+ fmt += 'd';
+ SCOPED_TRACE(fmt);
+ EXPECT_TRUE(Run(fmt.c_str()));
+ EXPECT_EQ(fmt.find('-') == std::string::npos, !o.flags.left);
+ EXPECT_EQ(fmt.find('+') == std::string::npos, !o.flags.show_pos);
+ EXPECT_EQ(fmt.find(' ') == std::string::npos, !o.flags.sign_col);
+ EXPECT_EQ(fmt.find('#') == std::string::npos, !o.flags.alt);
+ EXPECT_EQ(fmt.find('0') == std::string::npos, !o.flags.zero);
+ }
+ }
+}
+
+TEST_F(ConsumeUnboundConversionTest, BasicFlag) {
+ // Flag is on
+ for (const char* fmt : {"d", "llx", "G", "1$X"}) {
+ SCOPED_TRACE(fmt);
+ EXPECT_TRUE(Run(fmt));
+ EXPECT_TRUE(o.flags.basic);
+ }
+
+ // Flag is off
+ for (const char* fmt : {"3d", ".llx", "-G", "1$#X"}) {
+ SCOPED_TRACE(fmt);
+ EXPECT_TRUE(Run(fmt));
+ EXPECT_FALSE(o.flags.basic);
+ }
+}
+
+struct SummarizeConsumer {
+ std::string* out;
+ explicit SummarizeConsumer(std::string* out) : out(out) {}
+
+ bool Append(string_view s) {
+ *out += "[" + std::string(s) + "]";
+ return true;
+ }
+
+ bool ConvertOne(const UnboundConversion& conv, string_view s) {
+ *out += "{";
+ *out += std::string(s);
+ *out += ":";
+ *out += std::to_string(conv.arg_position) + "$";
+ if (conv.width.is_from_arg()) {
+ *out += std::to_string(conv.width.get_from_arg()) + "$*";
+ }
+ if (conv.precision.is_from_arg()) {
+ *out += "." + std::to_string(conv.precision.get_from_arg()) + "$*";
+ }
+ *out += conv.conv.Char();
+ *out += "}";
+ return true;
+ }
+};
+
+std::string SummarizeParsedFormat(const ParsedFormatBase& pc) {
+ std::string out;
+ if (!pc.ProcessFormat(SummarizeConsumer(&out))) out += "!";
+ return out;
+}
+
+class ParsedFormatTest : public testing::Test {};
+
+TEST_F(ParsedFormatTest, ValueSemantics) {
+ ParsedFormatBase p1({}, true, {}); // empty format
+ EXPECT_EQ("", SummarizeParsedFormat(p1));
+
+ ParsedFormatBase p2 = p1; // copy construct (empty)
+ EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p2));
+
+ p1 = ParsedFormatBase("hello%s", true, {Conv::s}); // move assign
+ EXPECT_EQ("[hello]{s:1$s}", SummarizeParsedFormat(p1));
+
+ ParsedFormatBase p3 = p1; // copy construct (nonempty)
+ EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p3));
+
+ using std::swap;
+ swap(p1, p2);
+ EXPECT_EQ("", SummarizeParsedFormat(p1));
+ EXPECT_EQ("[hello]{s:1$s}", SummarizeParsedFormat(p2));
+ swap(p1, p2); // undo
+
+ p2 = p1; // copy assign
+ EXPECT_EQ(SummarizeParsedFormat(p1), SummarizeParsedFormat(p2));
+}
+
+struct ExpectParse {
+ const char* in;
+ std::initializer_list<Conv> conv_set;
+ const char* out;
+};
+
+TEST_F(ParsedFormatTest, Parsing) {
+ // Parse should be equivalent to that obtained by ConversionParseIterator.
+ // No need to retest the parsing edge cases here.
+ const ExpectParse kExpect[] = {
+ {"", {}, ""},
+ {"ab", {}, "[ab]"},
+ {"a%d", {Conv::d}, "[a]{d:1$d}"},
+ {"a%+d", {Conv::d}, "[a]{+d:1$d}"},
+ {"a% d", {Conv::d}, "[a]{ d:1$d}"},
+ {"a%b %d", {}, "[a]!"}, // stop after error
+ };
+ for (const auto& e : kExpect) {
+ SCOPED_TRACE(e.in);
+ EXPECT_EQ(e.out,
+ SummarizeParsedFormat(ParsedFormatBase(e.in, false, e.conv_set)));
+ }
+}
+
+TEST_F(ParsedFormatTest, ParsingFlagOrder) {
+ const ExpectParse kExpect[] = {
+ {"a%+ 0d", {Conv::d}, "[a]{+ 0d:1$d}"},
+ {"a%+0 d", {Conv::d}, "[a]{+0 d:1$d}"},
+ {"a%0+ d", {Conv::d}, "[a]{0+ d:1$d}"},
+ {"a% +0d", {Conv::d}, "[a]{ +0d:1$d}"},
+ {"a%0 +d", {Conv::d}, "[a]{0 +d:1$d}"},
+ {"a% 0+d", {Conv::d}, "[a]{ 0+d:1$d}"},
+ {"a%+ 0+d", {Conv::d}, "[a]{+ 0+d:1$d}"},
+ };
+ for (const auto& e : kExpect) {
+ SCOPED_TRACE(e.in);
+ EXPECT_EQ(e.out,
+ SummarizeParsedFormat(ParsedFormatBase(e.in, false, e.conv_set)));
+ }
+}
+
+} // namespace
+} // namespace str_format_internal
+} // namespace absl
diff --git a/absl/strings/str_format.h b/absl/strings/str_format.h
new file mode 100644
index 00000000..98e0fef4
--- /dev/null
+++ b/absl/strings/str_format.h
@@ -0,0 +1,512 @@
+//
+// Copyright 2018 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// -----------------------------------------------------------------------------
+// File: str_format.h
+// -----------------------------------------------------------------------------
+//
+// The `str_format` library is a typesafe replacement for the family of
+// `printf()` std::string formatting routines within the `<cstdio>` standard library
+// header. Like the `printf` family, the `str_format` uses a "format string" to
+// perform argument substitutions based on types.
+//
+// Example:
+//
+// std::string s = absl::StrFormat("%s %s You have $%d!", "Hello", name, dollars);
+//
+// The library consists of the following basic utilities:
+//
+// * `absl::StrFormat()`, a type-safe replacement for `std::sprintf()`, to
+// write a format std::string to a `string` value.
+// * `absl::StrAppendFormat()` to append a format std::string to a `string`
+// * `absl::StreamFormat()` to more efficiently write a format std::string to a
+// stream, such as`std::cout`.
+// * `absl::PrintF()`, `absl::FPrintF()` and `absl::SNPrintF()` as
+// replacements for `std::printf()`, `std::fprintf()` and `std::snprintf()`.
+//
+// Note: a version of `std::sprintf()` is not supported as it is
+// generally unsafe due to buffer overflows.
+//
+// Additionally, you can provide a format std::string (and its associated arguments)
+// using one of the following abstractions:
+//
+// * A `FormatSpec` class template fully encapsulates a format std::string and its
+// type arguments and is usually provided to `str_format` functions as a
+// variadic argument of type `FormatSpec<Arg...>`. The `FormatSpec<Args...>`
+// template is evaluated at compile-time, providing type safety.
+// * A `ParsedFormat` instance, which encapsulates a specific, pre-compiled
+// format std::string for a specific set of type(s), and which can be passed
+// between API boundaries. (The `FormatSpec` type should not be used
+// directly.)
+//
+// The `str_format` library provides the ability to output its format strings to
+// arbitrary sink types:
+//
+// * A generic `Format()` function to write outputs to arbitrary sink types,
+// which must implement a `RawSinkFormat` interface. (See
+// `str_format_sink.h` for more information.)
+//
+// * A `FormatUntyped()` function that is similar to `Format()` except it is
+// loosely typed. `FormatUntyped()` is not a template and does not perform
+// any compile-time checking of the format std::string; instead, it returns a
+// boolean from a runtime check.
+//
+// In addition, the `str_format` library provides extension points for
+// augmenting formatting to new types. These extensions are fully documented
+// within the `str_format_extension.h` header file.
+#ifndef ABSL_STRINGS_STR_FORMAT_H_
+#define ABSL_STRINGS_STR_FORMAT_H_
+
+#include <cstdio>
+#include <string>
+
+#include "absl/strings/internal/str_format/arg.h" // IWYU pragma: export
+#include "absl/strings/internal/str_format/bind.h" // IWYU pragma: export
+#include "absl/strings/internal/str_format/checker.h" // IWYU pragma: export
+#include "absl/strings/internal/str_format/extension.h" // IWYU pragma: export
+#include "absl/strings/internal/str_format/parser.h" // IWYU pragma: export
+
+namespace absl {
+
+// UntypedFormatSpec
+//
+// A type-erased class that can be used directly within untyped API entry
+// points. An `UntypedFormatSpec` is specifically used as an argument to
+// `FormatUntyped()`.
+//
+// Example:
+//
+// absl::UntypedFormatSpec format("%d");
+// std::string out;
+// CHECK(absl::FormatUntyped(&out, format, {absl::FormatArg(1)}));
+class UntypedFormatSpec {
+ public:
+ UntypedFormatSpec() = delete;
+ UntypedFormatSpec(const UntypedFormatSpec&) = delete;
+ UntypedFormatSpec& operator=(const UntypedFormatSpec&) = delete;
+
+ explicit UntypedFormatSpec(string_view s) : spec_(s) {}
+
+ protected:
+ explicit UntypedFormatSpec(const str_format_internal::ParsedFormatBase* pc)
+ : spec_(pc) {}
+
+ private:
+ friend str_format_internal::UntypedFormatSpecImpl;
+ str_format_internal::UntypedFormatSpecImpl spec_;
+};
+
+// FormatStreamed()
+//
+// Takes a streamable argument and returns an object that can print it
+// with '%s'. Allows printing of types that have an `operator<<` but no
+// intrinsic type support within `StrFormat()` itself.
+//
+// Example:
+//
+// absl::StrFormat("%s", absl::FormatStreamed(obj));
+template <typename T>
+str_format_internal::StreamedWrapper<T> FormatStreamed(const T& v) {
+ return str_format_internal::StreamedWrapper<T>(v);
+}
+
+// FormatCountCapture
+//
+// This class provides a way to safely wrap `StrFormat()` captures of `%n`
+// conversions, which denote the number of characters written by a formatting
+// operation to this point, into an integer value.
+//
+// This wrapper is designed to allow safe usage of `%n` within `StrFormat(); in
+// the `printf()` family of functions, `%n` is not safe to use, as the `int *`
+// buffer can be used to capture arbitrary data.
+//
+// Example:
+//
+// int n = 0;
+// std::string s = absl::StrFormat("%s%d%n", "hello", 123,
+// absl::FormatCountCapture(&n));
+// EXPECT_EQ(8, n);
+class FormatCountCapture {
+ public:
+ explicit FormatCountCapture(int* p) : p_(p) {}
+
+ private:
+ // FormatCountCaptureHelper is used to define FormatConvertImpl() for this
+ // class.
+ friend struct str_format_internal::FormatCountCaptureHelper;
+ // Unused() is here because of the false positive from -Wunused-private-field
+ // p_ is used in the templated function of the friend FormatCountCaptureHelper
+ // class.
+ int* Unused() { return p_; }
+ int* p_;
+};
+
+// FormatSpec
+//
+// The `FormatSpec` type defines the makeup of a format std::string within the
+// `str_format` library. You should not need to use or manipulate this type
+// directly. A `FormatSpec` is a variadic class template that is evaluated at
+// compile-time, according to the format std::string and arguments that are passed
+// to it.
+//
+// For a `FormatSpec` to be valid at compile-time, it must be provided as
+// either:
+//
+// * A `constexpr` literal or `absl::string_view`, which is how it most often
+// used.
+// * A `ParsedFormat` instantiation, which ensures the format std::string is
+// valid before use. (See below.)
+//
+// Example:
+//
+// // Provided as a std::string literal.
+// absl::StrFormat("Welcome to %s, Number %d!", "The Village", 6);
+//
+// // Provided as a constexpr absl::string_view.
+// constexpr absl::string_view formatString = "Welcome to %s, Number %d!";
+// absl::StrFormat(formatString, "The Village", 6);
+//
+// // Provided as a pre-compiled ParsedFormat object.
+// // Note that this example is useful only for illustration purposes.
+// absl::ParsedFormat<'s', 'd'> formatString("Welcome to %s, Number %d!");
+// absl::StrFormat(formatString, "TheVillage", 6);
+//
+// A format std::string generally follows the POSIX syntax as used within the POSIX
+// `printf` specification.
+//
+// (See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/printf.html.)
+//
+// In specific, the `FormatSpec` supports the following type specifiers:
+// * `c` for characters
+// * `s` for strings
+// * `d` or `i` for integers
+// * `o` for unsigned integer conversions into octal
+// * `x` or `X` for unsigned integer conversions into hex
+// * `u` for unsigned integers
+// * `f` or `F` for floating point values into decimal notation
+// * `e` or `E` for floating point values into exponential notation
+// * `a` or `A` for floating point values into hex exponential notation
+// * `g` or `G` for floating point values into decimal or exponential
+// notation based on their precision
+// * `p` for pointer address values
+// * `n` for the special case of writing out the number of characters
+// written to this point. The resulting value must be captured within an
+// `absl::FormatCountCapture` type.
+//
+// NOTE: `o`, `x\X` and `u` will convert signed values to their unsigned
+// counterpart before formatting.
+//
+// Examples:
+// "%c", 'a' -> "a"
+// "%c", 32 -> " "
+// "%s", "C" -> "C"
+// "%s", std::string("C++") -> "C++"
+// "%d", -10 -> "-10"
+// "%o", 10 -> "12"
+// "%x", 16 -> "10"
+// "%f", 123456789 -> "123456789.000000"
+// "%e", .01 -> "1.00000e-2"
+// "%a", -3.0 -> "-0x1.8p+1"
+// "%g", .01 -> "1e-2"
+// "%p", *int -> "0x7ffdeb6ad2a4"
+//
+// int n = 0;
+// std::string s = absl::StrFormat(
+// "%s%d%n", "hello", 123, absl::FormatCountCapture(&n));
+// EXPECT_EQ(8, n);
+//
+// The `FormatSpec` intrinsically supports all of these fundamental C++ types:
+//
+// * Characters: `char`, `signed char`, `unsigned char`
+// * Integers: `int`, `short`, `unsigned short`, `unsigned`, `long`,
+// `unsigned long`, `long long`, `unsigned long long`
+// * Floating-point: `float`, `double`, `long double`
+//
+// However, in the `str_format` library, a format conversion specifies a broader
+// C++ conceptual category instead of an exact type. For example, `%s` binds to
+// any std::string-like argument, so `std::string`, `absl::string_view`, and
+// `const char*` are all accepted. Likewise, `%d` accepts any integer-like
+// argument, etc.
+
+template <typename... Args>
+using FormatSpec =
+ typename str_format_internal::FormatSpecDeductionBarrier<Args...>::type;
+
+using absl::str_format_internal::ExtendedParsedFormat;
+
+// ParsedFormat
+//
+// A `ParsedFormat` is a class template representing a preparsed `FormatSpec`,
+// with template arguments specifying the conversion characters used within the
+// format std::string. Such characters must be valid format type specifiers, and
+// these type specifiers are checked at compile-time.
+//
+// Instances of `ParsedFormat` can be created, copied, and reused to speed up
+// formatting loops. A `ParsedFormat` may either be constructed statically, or
+// dynamically through its `New()` factory function, which only constructs a
+// runtime object if the format is valid at that time.
+//
+// Example:
+//
+// // Verified at compile time.
+// absl::ParsedFormat<'s', 'd'> formatString("Welcome to %s, Number %d!");
+// absl::StrFormat(formatString, "TheVillage", 6);
+//
+// // Verified at runtime.
+// auto format_runtime = absl::ParsedFormat<'d'>::New(format_string);
+// if (format_runtime) {
+// value = absl::StrFormat(*format_runtime, i);
+// } else {
+// ... error case ...
+// }
+template <char... Conv>
+using ParsedFormat = str_format_internal::ExtendedParsedFormat<
+ str_format_internal::ConversionCharToConv(Conv)...>;
+
+// StrFormat()
+//
+// Returns a `string` given a `printf()`-style format std::string and zero or more
+// additional arguments. Use it as you would `sprintf()`. `StrFormat()` is the
+// primary formatting function within the `str_format` library, and should be
+// used in most cases where you need type-safe conversion of types into
+// formatted strings.
+//
+// The format std::string generally consists of ordinary character data along with
+// one or more format conversion specifiers (denoted by the `%` character).
+// Ordinary character data is returned unchanged into the result std::string, while
+// each conversion specification performs a type substitution from
+// `StrFormat()`'s other arguments. See the comments for `FormatSpec` for full
+// information on the makeup of this format std::string.
+//
+// Example:
+//
+// std::string s = absl::StrFormat(
+// "Welcome to %s, Number %d!", "The Village", 6);
+// EXPECT_EQ("Welcome to The Village, Number 6!", s);
+//
+// Returns an empty std::string in case of error.
+template <typename... Args>
+ABSL_MUST_USE_RESULT std::string StrFormat(const FormatSpec<Args...>& format,
+ const Args&... args) {
+ return str_format_internal::FormatPack(
+ str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// StrAppendFormat()
+//
+// Appends to a `dst` std::string given a format std::string, and zero or more additional
+// arguments, returning `*dst` as a convenience for chaining purposes. Appends
+// nothing in case of error (but possibly alters its capacity).
+//
+// Example:
+//
+// std::string orig("For example PI is approximately ");
+// std::cout << StrAppendFormat(&orig, "%12.6f", 3.14);
+template <typename... Args>
+std::string& StrAppendFormat(std::string* dst, const FormatSpec<Args...>& format,
+ const Args&... args) {
+ return str_format_internal::AppendPack(
+ dst, str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// StreamFormat()
+//
+// Writes to an output stream given a format std::string and zero or more arguments,
+// generally in a manner that is more efficient than streaming the result of
+// `absl:: StrFormat()`. The returned object must be streamed before the full
+// expression ends.
+//
+// Example:
+//
+// std::cout << StreamFormat("%12.6f", 3.14);
+template <typename... Args>
+ABSL_MUST_USE_RESULT str_format_internal::Streamable StreamFormat(
+ const FormatSpec<Args...>& format, const Args&... args) {
+ return str_format_internal::Streamable(
+ str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// PrintF()
+//
+// Writes to stdout given a format std::string and zero or more arguments. This
+// function is functionally equivalent to `std::print()` (and type-safe); prefer
+// `absl::PrintF()` over `std::printf()`.
+//
+// Example:
+//
+// std::string_view s = "Ulaanbaatar";
+// absl::PrintF("The capital of Mongolia is: %s \n", s);
+//
+// Outputs: "The capital of Mongolia is Ulaanbaatar"
+//
+template <typename... Args>
+int PrintF(const FormatSpec<Args...>& format, const Args&... args) {
+ return str_format_internal::FprintF(
+ stdout, str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// FPrintF()
+//
+// Writes to a file given a format std::string and zero or more arguments. This
+// function is functionally equivalent to `std::fprint()` (and type-safe);
+// prefer `absl::FPrintF()` over `std::fprintf()`.
+//
+// Example:
+//
+// std::string_view s = "Ulaanbaatar";
+// absl::FPrintF("The capital of Mongolia is: %s \n", s);
+//
+// Outputs: "The capital of Mongolia is Ulaanbaatar"
+//
+template <typename... Args>
+int FPrintF(std::FILE* output, const FormatSpec<Args...>& format,
+ const Args&... args) {
+ return str_format_internal::FprintF(
+ output, str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// SNPrintF()
+//
+// Writes to a sized buffer given a format std::string and zero or more arguments.
+// This function is functionally equivalent to `std::snprint()` (and type-safe);
+// prefer `absl::SNPrintF()` over `std::snprintf()`.
+//
+// Example:
+//
+// std::string_view s = "Ulaanbaatar";
+// absl::FPrintF("The capital of Mongolia is: %s \n", s);
+//
+// Outputs: "The capital of Mongolia is Ulaanbaatar"
+//
+template <typename... Args>
+int SNPrintF(char* output, std::size_t size, const FormatSpec<Args...>& format,
+ const Args&... args) {
+ return str_format_internal::SnprintF(
+ output, size, str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// -----------------------------------------------------------------------------
+// Custom Output Formatting Functions
+// -----------------------------------------------------------------------------
+
+// FormatRawSink
+//
+// FormatRawSink is a type erased wrapper around arbitrary sink objects
+// specifically used as an argument to `Format()`.
+// FormatRawSink does not own the passed sink object. The passed object must
+// outlive the FormatRawSink.
+class FormatRawSink {
+ public:
+ // Implicitly convert from any type that provides the hook function as
+ // described above.
+ template <typename T,
+ typename = typename std::enable_if<std::is_constructible<
+ str_format_internal::FormatRawSinkImpl, T*>::value>::type>
+ FormatRawSink(T* raw) // NOLINT
+ : sink_(raw) {}
+
+ private:
+ friend str_format_internal::FormatRawSinkImpl;
+ str_format_internal::FormatRawSinkImpl sink_;
+};
+
+// Format()
+//
+// Writes a formatted std::string to an arbitrary sink object (implementing the
+// `absl::FormatRawSink` interface), using a format std::string and zero or more
+// additional arguments.
+//
+// By default, `string` and `std::ostream` are supported as destination objects.
+//
+// `absl::Format()` is a generic version of `absl::StrFormat(), for custom
+// sinks. The format std::string, like format strings for `StrFormat()`, is checked
+// at compile-time.
+//
+// On failure, this function returns `false` and the state of the sink is
+// unspecified.
+template <typename... Args>
+bool Format(FormatRawSink raw_sink, const FormatSpec<Args...>& format,
+ const Args&... args) {
+ return str_format_internal::FormatUntyped(
+ str_format_internal::FormatRawSinkImpl::Extract(raw_sink),
+ str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {str_format_internal::FormatArgImpl(args)...});
+}
+
+// FormatArg
+//
+// A type-erased handle to a format argument specifically used as an argument to
+// `FormatUntyped()`. You may construct `FormatArg` by passing
+// reference-to-const of any printable type. `FormatArg` is both copyable and
+// assignable. The source data must outlive the `FormatArg` instance. See
+// example below.
+//
+using FormatArg = str_format_internal::FormatArgImpl;
+
+// FormatUntyped()
+//
+// Writes a formatted std::string to an arbitrary sink object (implementing the
+// `absl::FormatRawSink` interface), using an `UntypedFormatSpec` and zero or
+// more additional arguments.
+//
+// This function acts as the most generic formatting function in the
+// `str_format` library. The caller provides a raw sink, an unchecked format
+// std::string, and (usually) a runtime specified list of arguments; no compile-time
+// checking of formatting is performed within this function. As a result, a
+// caller should check the return value to verify that no error occurred.
+// On failure, this function returns `false` and the state of the sink is
+// unspecified.
+//
+// The arguments are provided in an `absl::Span<const absl::FormatArg>`.
+// Each `absl::FormatArg` object binds to a single argument and keeps a
+// reference to it. The values used to create the `FormatArg` objects must
+// outlive this function call. (See `str_format_arg.h` for information on
+// the `FormatArg` class.)_
+//
+// Example:
+//
+// std::optional<std::string> FormatDynamic(const std::string& in_format,
+// const vector<std::string>& in_args) {
+// std::string out;
+// std::vector<absl::FormatArg> args;
+// for (const auto& v : in_args) {
+// // It is important that 'v' is a reference to the objects in in_args.
+// // The values we pass to FormatArg must outlive the call to
+// // FormatUntyped.
+// args.emplace_back(v);
+// }
+// absl::UntypedFormatSpec format(in_format);
+// if (!absl::FormatUntyped(&out, format, args)) {
+// return std::nullopt;
+// }
+// return std::move(out);
+// }
+//
+ABSL_MUST_USE_RESULT inline bool FormatUntyped(
+ FormatRawSink raw_sink, const UntypedFormatSpec& format,
+ absl::Span<const FormatArg> args) {
+ return str_format_internal::FormatUntyped(
+ str_format_internal::FormatRawSinkImpl::Extract(raw_sink),
+ str_format_internal::UntypedFormatSpecImpl::Extract(format), args);
+}
+
+} // namespace absl
+#endif // ABSL_STRINGS_STR_FORMAT_H_
diff --git a/absl/strings/str_format_test.cc b/absl/strings/str_format_test.cc
new file mode 100644
index 00000000..fe742bf9
--- /dev/null
+++ b/absl/strings/str_format_test.cc
@@ -0,0 +1,603 @@
+
+#include <cstdarg>
+#include <cstdint>
+#include <cstdio>
+#include <string>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "absl/strings/str_format.h"
+#include "absl/strings/string_view.h"
+
+namespace absl {
+namespace {
+using str_format_internal::FormatArgImpl;
+
+class FormatEntryPointTest : public ::testing::Test { };
+
+TEST_F(FormatEntryPointTest, Format) {
+ std::string sink;
+ EXPECT_TRUE(Format(&sink, "A format %d", 123));
+ EXPECT_EQ("A format 123", sink);
+ sink.clear();
+
+ ParsedFormat<'d'> pc("A format %d");
+ EXPECT_TRUE(Format(&sink, pc, 123));
+ EXPECT_EQ("A format 123", sink);
+}
+TEST_F(FormatEntryPointTest, UntypedFormat) {
+ constexpr const char* formats[] = {
+ "",
+ "a",
+ "%80d",
+#if !defined(_MSC_VER) && !defined(__ANDROID__)
+ // MSVC and Android don't support positional syntax.
+ "complicated multipart %% %1$d format %1$0999d",
+#endif // _MSC_VER
+ };
+ for (const char* fmt : formats) {
+ std::string actual;
+ int i = 123;
+ FormatArgImpl arg_123(i);
+ absl::Span<const FormatArgImpl> args(&arg_123, 1);
+ UntypedFormatSpec format(fmt);
+
+ EXPECT_TRUE(FormatUntyped(&actual, format, args));
+ char buf[4096]{};
+ snprintf(buf, sizeof(buf), fmt, 123);
+ EXPECT_EQ(
+ str_format_internal::FormatPack(
+ str_format_internal::UntypedFormatSpecImpl::Extract(format), args),
+ buf);
+ EXPECT_EQ(actual, buf);
+ }
+ // The internal version works with a preparsed format.
+ ParsedFormat<'d'> pc("A format %d");
+ int i = 345;
+ FormatArg arg(i);
+ std::string out;
+ EXPECT_TRUE(str_format_internal::FormatUntyped(
+ &out, str_format_internal::UntypedFormatSpecImpl(&pc), {&arg, 1}));
+ EXPECT_EQ("A format 345", out);
+}
+
+TEST_F(FormatEntryPointTest, StringFormat) {
+ EXPECT_EQ("123", StrFormat("%d", 123));
+ constexpr absl::string_view view("=%d=", 4);
+ EXPECT_EQ("=123=", StrFormat(view, 123));
+}
+
+TEST_F(FormatEntryPointTest, AppendFormat) {
+ std::string s;
+ std::string& r = StrAppendFormat(&s, "%d", 123);
+ EXPECT_EQ(&s, &r); // should be same object
+ EXPECT_EQ("123", r);
+}
+
+TEST_F(FormatEntryPointTest, AppendFormatFail) {
+ std::string s = "orig";
+
+ UntypedFormatSpec format(" more %d");
+ FormatArgImpl arg("not an int");
+
+ EXPECT_EQ("orig",
+ str_format_internal::AppendPack(
+ &s, str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ {&arg, 1}));
+}
+
+
+TEST_F(FormatEntryPointTest, ManyArgs) {
+ EXPECT_EQ("24", StrFormat("%24$d", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
+ 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24));
+ EXPECT_EQ("60", StrFormat("%60$d", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
+ 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
+ 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
+ 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
+ 53, 54, 55, 56, 57, 58, 59, 60));
+}
+
+TEST_F(FormatEntryPointTest, Preparsed) {
+ ParsedFormat<'d'> pc("%d");
+ EXPECT_EQ("123", StrFormat(pc, 123));
+ // rvalue ok?
+ EXPECT_EQ("123", StrFormat(ParsedFormat<'d'>("%d"), 123));
+ constexpr absl::string_view view("=%d=", 4);
+ EXPECT_EQ("=123=", StrFormat(ParsedFormat<'d'>(view), 123));
+}
+
+TEST_F(FormatEntryPointTest, FormatCountCapture) {
+ int n = 0;
+ EXPECT_EQ("", StrFormat("%n", FormatCountCapture(&n)));
+ EXPECT_EQ(0, n);
+ EXPECT_EQ("123", StrFormat("%d%n", 123, FormatCountCapture(&n)));
+ EXPECT_EQ(3, n);
+}
+
+TEST_F(FormatEntryPointTest, FormatCountCaptureWrongType) {
+ // Should reject int*.
+ int n = 0;
+ UntypedFormatSpec format("%d%n");
+ int i = 123, *ip = &n;
+ FormatArgImpl args[2] = {FormatArgImpl(i), FormatArgImpl(ip)};
+
+ EXPECT_EQ("", str_format_internal::FormatPack(
+ str_format_internal::UntypedFormatSpecImpl::Extract(format),
+ absl::MakeSpan(args)));
+}
+
+TEST_F(FormatEntryPointTest, FormatCountCaptureMultiple) {
+ int n1 = 0;
+ int n2 = 0;
+ EXPECT_EQ(" 1 2",
+ StrFormat("%5d%n%10d%n", 1, FormatCountCapture(&n1), 2,
+ FormatCountCapture(&n2)));
+ EXPECT_EQ(5, n1);
+ EXPECT_EQ(15, n2);
+}
+
+TEST_F(FormatEntryPointTest, FormatCountCaptureExample) {
+ int n;
+ std::string s;
+ StrAppendFormat(&s, "%s: %n%s\n", "(1,1)", FormatCountCapture(&n), "(1,2)");
+ StrAppendFormat(&s, "%*s%s\n", n, "", "(2,2)");
+ EXPECT_EQ(7, n);
+ EXPECT_EQ(
+ "(1,1): (1,2)\n"
+ " (2,2)\n",
+ s);
+}
+
+TEST_F(FormatEntryPointTest, Stream) {
+ const std::string formats[] = {
+ "",
+ "a",
+ "%80d",
+#if !defined(_MSC_VER) && !defined(__ANDROID__)
+ // MSVC doesn't support positional syntax.
+ "complicated multipart %% %1$d format %1$080d",
+#endif // _MSC_VER
+ };
+ std::string buf(4096, '\0');
+ for (const auto& fmt : formats) {
+ const auto parsed = ParsedFormat<'d'>::NewAllowIgnored(fmt);
+ std::ostringstream oss;
+ oss << StreamFormat(*parsed, 123);
+ int fmt_result = snprintf(&*buf.begin(), buf.size(), fmt.c_str(), 123);
+ ASSERT_TRUE(oss) << fmt;
+ ASSERT_TRUE(fmt_result >= 0 && static_cast<size_t>(fmt_result) < buf.size())
+ << fmt_result;
+ EXPECT_EQ(buf.c_str(), oss.str());
+ }
+}
+
+TEST_F(FormatEntryPointTest, StreamOk) {
+ std::ostringstream oss;
+ oss << StreamFormat("hello %d", 123);
+ EXPECT_EQ("hello 123", oss.str());
+ EXPECT_TRUE(oss.good());
+}
+
+TEST_F(FormatEntryPointTest, StreamFail) {
+ std::ostringstream oss;
+ UntypedFormatSpec format("hello %d");
+ FormatArgImpl arg("non-numeric");
+ oss << str_format_internal::Streamable(
+ str_format_internal::UntypedFormatSpecImpl::Extract(format), {&arg, 1});
+ EXPECT_EQ("hello ", oss.str()); // partial write
+ EXPECT_TRUE(oss.fail());
+}
+
+std::string WithSnprintf(const char* fmt, ...) {
+ std::string buf;
+ buf.resize(128);
+ va_list va;
+ va_start(va, fmt);
+ int r = vsnprintf(&*buf.begin(), buf.size(), fmt, va);
+ va_end(va);
+ EXPECT_GE(r, 0);
+ EXPECT_LT(r, buf.size());
+ buf.resize(r);
+ return buf;
+}
+
+TEST_F(FormatEntryPointTest, FloatPrecisionArg) {
+ // Test that positional parameters for width and precision
+ // are indexed to precede the value.
+ // Also sanity check the same formats against snprintf.
+ EXPECT_EQ("0.1", StrFormat("%.1f", 0.1));
+ EXPECT_EQ("0.1", WithSnprintf("%.1f", 0.1));
+ EXPECT_EQ(" 0.1", StrFormat("%*.1f", 5, 0.1));
+ EXPECT_EQ(" 0.1", WithSnprintf("%*.1f", 5, 0.1));
+ EXPECT_EQ("0.1", StrFormat("%.*f", 1, 0.1));
+ EXPECT_EQ("0.1", WithSnprintf("%.*f", 1, 0.1));
+ EXPECT_EQ(" 0.1", StrFormat("%*.*f", 5, 1, 0.1));
+ EXPECT_EQ(" 0.1", WithSnprintf("%*.*f", 5, 1, 0.1));
+}
+namespace streamed_test {
+struct X {};
+std::ostream& operator<<(std::ostream& os, const X&) {
+ return os << "X";
+}
+} // streamed_test
+
+TEST_F(FormatEntryPointTest, FormatStreamed) {
+ EXPECT_EQ("123", StrFormat("%s", FormatStreamed(123)));
+ EXPECT_EQ(" 123", StrFormat("%5s", FormatStreamed(123)));
+ EXPECT_EQ("123 ", StrFormat("%-5s", FormatStreamed(123)));
+ EXPECT_EQ("X", StrFormat("%s", FormatStreamed(streamed_test::X())));
+ EXPECT_EQ("123", StrFormat("%s", FormatStreamed(StreamFormat("%d", 123))));
+}
+
+// Helper class that creates a temporary file and exposes a FILE* to it.
+// It will close the file on destruction.
+class TempFile {
+ public:
+ TempFile() : file_(std::tmpfile()) {}
+ ~TempFile() { std::fclose(file_); }
+
+ std::FILE* file() const { return file_; }
+
+ // Read the file into a std::string.
+ std::string ReadFile() {
+ std::fseek(file_, 0, SEEK_END);
+ int size = std::ftell(file_);
+ std::rewind(file_);
+ std::string str(2 * size, ' ');
+ int read_bytes = std::fread(&str[0], 1, str.size(), file_);
+ EXPECT_EQ(read_bytes, size);
+ str.resize(read_bytes);
+ EXPECT_TRUE(std::feof(file_));
+ return str;
+ }
+
+ private:
+ std::FILE* file_;
+};
+
+TEST_F(FormatEntryPointTest, FPrintF) {
+ TempFile tmp;
+ int result =
+ FPrintF(tmp.file(), "STRING: %s NUMBER: %010d", std::string("ABC"), -19);
+ EXPECT_EQ(result, 30);
+ EXPECT_EQ(tmp.ReadFile(), "STRING: ABC NUMBER: -000000019");
+}
+
+TEST_F(FormatEntryPointTest, FPrintFError) {
+ errno = 0;
+ int result = FPrintF(stdin, "ABC");
+ EXPECT_LT(result, 0);
+ EXPECT_EQ(errno, EBADF);
+}
+
+#if __GNUC__
+TEST_F(FormatEntryPointTest, FprintfTooLarge) {
+ std::FILE* f = std::fopen("/dev/null", "w");
+ int width = 2000000000;
+ errno = 0;
+ int result = FPrintF(f, "%*d %*d", width, 0, width, 0);
+ EXPECT_LT(result, 0);
+ EXPECT_EQ(errno, EFBIG);
+ std::fclose(f);
+}
+
+TEST_F(FormatEntryPointTest, PrintF) {
+ int stdout_tmp = dup(STDOUT_FILENO);
+
+ TempFile tmp;
+ std::fflush(stdout);
+ dup2(fileno(tmp.file()), STDOUT_FILENO);
+
+ int result = PrintF("STRING: %s NUMBER: %010d", std::string("ABC"), -19);
+
+ std::fflush(stdout);
+ dup2(stdout_tmp, STDOUT_FILENO);
+ close(stdout_tmp);
+
+ EXPECT_EQ(result, 30);
+ EXPECT_EQ(tmp.ReadFile(), "STRING: ABC NUMBER: -000000019");
+}
+#endif // __GNUC__
+
+TEST_F(FormatEntryPointTest, SNPrintF) {
+ char buffer[16];
+ int result =
+ SNPrintF(buffer, sizeof(buffer), "STRING: %s", std::string("ABC"));
+ EXPECT_EQ(result, 11);
+ EXPECT_EQ(std::string(buffer), "STRING: ABC");
+
+ result = SNPrintF(buffer, sizeof(buffer), "NUMBER: %d", 123456);
+ EXPECT_EQ(result, 14);
+ EXPECT_EQ(std::string(buffer), "NUMBER: 123456");
+
+ result = SNPrintF(buffer, sizeof(buffer), "NUMBER: %d", 1234567);
+ EXPECT_EQ(result, 15);
+ EXPECT_EQ(std::string(buffer), "NUMBER: 1234567");
+
+ result = SNPrintF(buffer, sizeof(buffer), "NUMBER: %d", 12345678);
+ EXPECT_EQ(result, 16);
+ EXPECT_EQ(std::string(buffer), "NUMBER: 1234567");
+
+ result = SNPrintF(buffer, sizeof(buffer), "NUMBER: %d", 123456789);
+ EXPECT_EQ(result, 17);
+ EXPECT_EQ(std::string(buffer), "NUMBER: 1234567");
+
+ result = SNPrintF(nullptr, 0, "Just checking the %s of the output.", "size");
+ EXPECT_EQ(result, 37);
+}
+
+TEST(StrFormat, BehavesAsDocumented) {
+ std::string s = absl::StrFormat("%s, %d!", "Hello", 123);
+ EXPECT_EQ("Hello, 123!", s);
+ // The format of a replacement is
+ // '%'[position][flags][width['.'precision]][length_modifier][format]
+ EXPECT_EQ(absl::StrFormat("%1$+3.2Lf", 1.1), "+1.10");
+ // Text conversion:
+ // "c" - Character. Eg: 'a' -> "A", 20 -> " "
+ EXPECT_EQ(StrFormat("%c", 'a'), "a");
+ EXPECT_EQ(StrFormat("%c", 0x20), " ");
+ // Formats char and integral types: int, long, uint64_t, etc.
+ EXPECT_EQ(StrFormat("%c", int{'a'}), "a");
+ EXPECT_EQ(StrFormat("%c", long{'a'}), "a"); // NOLINT
+ EXPECT_EQ(StrFormat("%c", uint64_t{'a'}), "a");
+ // "s" - std::string Eg: "C" -> "C", std::string("C++") -> "C++"
+ // Formats std::string, char*, string_view, and Cord.
+ EXPECT_EQ(StrFormat("%s", "C"), "C");
+ EXPECT_EQ(StrFormat("%s", std::string("C++")), "C++");
+ EXPECT_EQ(StrFormat("%s", string_view("view")), "view");
+ // Integral Conversion
+ // These format integral types: char, int, long, uint64_t, etc.
+ EXPECT_EQ(StrFormat("%d", char{10}), "10");
+ EXPECT_EQ(StrFormat("%d", int{10}), "10");
+ EXPECT_EQ(StrFormat("%d", long{10}), "10"); // NOLINT
+ EXPECT_EQ(StrFormat("%d", uint64_t{10}), "10");
+ // d,i - signed decimal Eg: -10 -> "-10"
+ EXPECT_EQ(StrFormat("%d", -10), "-10");
+ EXPECT_EQ(StrFormat("%i", -10), "-10");
+ // o - octal Eg: 10 -> "12"
+ EXPECT_EQ(StrFormat("%o", 10), "12");
+ // u - unsigned decimal Eg: 10 -> "10"
+ EXPECT_EQ(StrFormat("%u", 10), "10");
+ // x/X - lower,upper case hex Eg: 10 -> "a"/"A"
+ EXPECT_EQ(StrFormat("%x", 10), "a");
+ EXPECT_EQ(StrFormat("%X", 10), "A");
+ // Floating-point, with upper/lower-case output.
+ // These format floating points types: float, double, long double, etc.
+ EXPECT_EQ(StrFormat("%.1f", float{1}), "1.0");
+ EXPECT_EQ(StrFormat("%.1f", double{1}), "1.0");
+ const long double long_double = 1.0;
+ EXPECT_EQ(StrFormat("%.1f", long_double), "1.0");
+ // These also format integral types: char, int, long, uint64_t, etc.:
+ EXPECT_EQ(StrFormat("%.1f", char{1}), "1.0");
+ EXPECT_EQ(StrFormat("%.1f", int{1}), "1.0");
+ EXPECT_EQ(StrFormat("%.1f", long{1}), "1.0"); // NOLINT
+ EXPECT_EQ(StrFormat("%.1f", uint64_t{1}), "1.0");
+ // f/F - decimal. Eg: 123456789 -> "123456789.000000"
+ EXPECT_EQ(StrFormat("%f", 123456789), "123456789.000000");
+ EXPECT_EQ(StrFormat("%F", 123456789), "123456789.000000");
+ // e/E - exponentiated Eg: .01 -> "1.00000e-2"/"1.00000E-2"
+ EXPECT_EQ(StrFormat("%e", .01), "1.000000e-02");
+ EXPECT_EQ(StrFormat("%E", .01), "1.000000E-02");
+ // g/G - exponentiate to fit Eg: .01 -> "0.01", 1e10 ->"1e+10"/"1E+10"
+ EXPECT_EQ(StrFormat("%g", .01), "0.01");
+ EXPECT_EQ(StrFormat("%g", 1e10), "1e+10");
+ EXPECT_EQ(StrFormat("%G", 1e10), "1E+10");
+ // a/A - lower,upper case hex Eg: -3.0 -> "-0x1.8p+1"/"-0X1.8P+1"
+
+// On NDK r16, there is a regression in hexfloat formatting.
+#if !defined(__NDK_MAJOR__) || __NDK_MAJOR__ != 16
+ EXPECT_EQ(StrFormat("%.1a", -3.0), "-0x1.8p+1"); // .1 to fix MSVC output
+ EXPECT_EQ(StrFormat("%.1A", -3.0), "-0X1.8P+1"); // .1 to fix MSVC output
+#endif
+
+ // Other conversion
+ int64_t value = 0x7ffdeb6;
+ auto ptr_value = static_cast<uintptr_t>(value);
+ const int& something = *reinterpret_cast<const int*>(ptr_value);
+ EXPECT_EQ(StrFormat("%p", &something), StrFormat("0x%x", ptr_value));
+
+ // Output widths are supported, with optional flags.
+ EXPECT_EQ(StrFormat("%3d", 1), " 1");
+ EXPECT_EQ(StrFormat("%3d", 123456), "123456");
+ EXPECT_EQ(StrFormat("%06.2f", 1.234), "001.23");
+ EXPECT_EQ(StrFormat("%+d", 1), "+1");
+ EXPECT_EQ(StrFormat("% d", 1), " 1");
+ EXPECT_EQ(StrFormat("%-4d", -1), "-1 ");
+ EXPECT_EQ(StrFormat("%#o", 10), "012");
+ EXPECT_EQ(StrFormat("%#x", 15), "0xf");
+ EXPECT_EQ(StrFormat("%04d", 8), "0008");
+ // Posix positional substitution.
+ EXPECT_EQ(absl::StrFormat("%2$s, %3$s, %1$s!", "vici", "veni", "vidi"),
+ "veni, vidi, vici!");
+ // Length modifiers are ignored.
+ EXPECT_EQ(StrFormat("%hhd", int{1}), "1");
+ EXPECT_EQ(StrFormat("%hd", int{1}), "1");
+ EXPECT_EQ(StrFormat("%ld", int{1}), "1");
+ EXPECT_EQ(StrFormat("%lld", int{1}), "1");
+ EXPECT_EQ(StrFormat("%Ld", int{1}), "1");
+ EXPECT_EQ(StrFormat("%jd", int{1}), "1");
+ EXPECT_EQ(StrFormat("%zd", int{1}), "1");
+ EXPECT_EQ(StrFormat("%td", int{1}), "1");
+ EXPECT_EQ(StrFormat("%qd", int{1}), "1");
+}
+
+using str_format_internal::ExtendedParsedFormat;
+using str_format_internal::ParsedFormatBase;
+
+struct SummarizeConsumer {
+ std::string* out;
+ explicit SummarizeConsumer(std::string* out) : out(out) {}
+
+ bool Append(string_view s) {
+ *out += "[" + std::string(s) + "]";
+ return true;
+ }
+
+ bool ConvertOne(const str_format_internal::UnboundConversion& conv,
+ string_view s) {
+ *out += "{";
+ *out += std::string(s);
+ *out += ":";
+ *out += std::to_string(conv.arg_position) + "$";
+ if (conv.width.is_from_arg()) {
+ *out += std::to_string(conv.width.get_from_arg()) + "$*";
+ }
+ if (conv.precision.is_from_arg()) {
+ *out += "." + std::to_string(conv.precision.get_from_arg()) + "$*";
+ }
+ *out += conv.conv.Char();
+ *out += "}";
+ return true;
+ }
+};
+
+std::string SummarizeParsedFormat(const ParsedFormatBase& pc) {
+ std::string out;
+ if (!pc.ProcessFormat(SummarizeConsumer(&out))) out += "!";
+ return out;
+}
+
+class ParsedFormatTest : public testing::Test {};
+
+TEST_F(ParsedFormatTest, SimpleChecked) {
+ EXPECT_EQ("[ABC]{d:1$d}[DEF]",
+ SummarizeParsedFormat(ParsedFormat<'d'>("ABC%dDEF")));
+ EXPECT_EQ("{s:1$s}[FFF]{d:2$d}[ZZZ]{f:3$f}",
+ SummarizeParsedFormat(ParsedFormat<'s', 'd', 'f'>("%sFFF%dZZZ%f")));
+ EXPECT_EQ("{s:1$s}[ ]{.*d:3$.2$*d}",
+ SummarizeParsedFormat(ParsedFormat<'s', '*', 'd'>("%s %.*d")));
+}
+
+TEST_F(ParsedFormatTest, SimpleUncheckedCorrect) {
+ auto f = ParsedFormat<'d'>::New("ABC%dDEF");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]{d:1$d}[DEF]", SummarizeParsedFormat(*f));
+
+ std::string format = "%sFFF%dZZZ%f";
+ auto f2 = ParsedFormat<'s', 'd', 'f'>::New(format);
+
+ ASSERT_TRUE(f2);
+ EXPECT_EQ("{s:1$s}[FFF]{d:2$d}[ZZZ]{f:3$f}", SummarizeParsedFormat(*f2));
+
+ f2 = ParsedFormat<'s', 'd', 'f'>::New("%s %d %f");
+
+ ASSERT_TRUE(f2);
+ EXPECT_EQ("{s:1$s}[ ]{d:2$d}[ ]{f:3$f}", SummarizeParsedFormat(*f2));
+
+ auto star = ParsedFormat<'*', 'd'>::New("%*d");
+ ASSERT_TRUE(star);
+ EXPECT_EQ("{*d:2$1$*d}", SummarizeParsedFormat(*star));
+
+ auto dollar = ParsedFormat<'d', 's'>::New("%2$s %1$d");
+ ASSERT_TRUE(dollar);
+ EXPECT_EQ("{2$s:2$s}[ ]{1$d:1$d}", SummarizeParsedFormat(*dollar));
+ // with reuse
+ dollar = ParsedFormat<'d', 's'>::New("%2$s %1$d %1$d");
+ ASSERT_TRUE(dollar);
+ EXPECT_EQ("{2$s:2$s}[ ]{1$d:1$d}[ ]{1$d:1$d}",
+ SummarizeParsedFormat(*dollar));
+}
+
+TEST_F(ParsedFormatTest, SimpleUncheckedIgnoredArgs) {
+ EXPECT_FALSE((ParsedFormat<'d', 's'>::New("ABC")));
+ EXPECT_FALSE((ParsedFormat<'d', 's'>::New("%dABC")));
+ EXPECT_FALSE((ParsedFormat<'d', 's'>::New("ABC%2$s")));
+ auto f = ParsedFormat<'d', 's'>::NewAllowIgnored("ABC");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]", SummarizeParsedFormat(*f));
+ f = ParsedFormat<'d', 's'>::NewAllowIgnored("%dABC");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("{d:1$d}[ABC]", SummarizeParsedFormat(*f));
+ f = ParsedFormat<'d', 's'>::NewAllowIgnored("ABC%2$s");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]{2$s:2$s}", SummarizeParsedFormat(*f));
+}
+
+TEST_F(ParsedFormatTest, SimpleUncheckedUnsupported) {
+ EXPECT_FALSE(ParsedFormat<'d'>::New("%1$d %1$x"));
+ EXPECT_FALSE(ParsedFormat<'x'>::New("%1$d %1$x"));
+}
+
+TEST_F(ParsedFormatTest, SimpleUncheckedIncorrect) {
+ EXPECT_FALSE(ParsedFormat<'d'>::New(""));
+
+ EXPECT_FALSE(ParsedFormat<'d'>::New("ABC%dDEF%d"));
+
+ std::string format = "%sFFF%dZZZ%f";
+ EXPECT_FALSE((ParsedFormat<'s', 'd', 'g'>::New(format)));
+}
+
+using str_format_internal::Conv;
+
+TEST_F(ParsedFormatTest, UncheckedCorrect) {
+ auto f = ExtendedParsedFormat<Conv::d>::New("ABC%dDEF");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]{d:1$d}[DEF]", SummarizeParsedFormat(*f));
+
+ std::string format = "%sFFF%dZZZ%f";
+ auto f2 =
+ ExtendedParsedFormat<Conv::string, Conv::d, Conv::floating>::New(format);
+
+ ASSERT_TRUE(f2);
+ EXPECT_EQ("{s:1$s}[FFF]{d:2$d}[ZZZ]{f:3$f}", SummarizeParsedFormat(*f2));
+
+ f2 = ExtendedParsedFormat<Conv::string, Conv::d, Conv::floating>::New(
+ "%s %d %f");
+
+ ASSERT_TRUE(f2);
+ EXPECT_EQ("{s:1$s}[ ]{d:2$d}[ ]{f:3$f}", SummarizeParsedFormat(*f2));
+
+ auto star = ExtendedParsedFormat<Conv::star, Conv::d>::New("%*d");
+ ASSERT_TRUE(star);
+ EXPECT_EQ("{*d:2$1$*d}", SummarizeParsedFormat(*star));
+
+ auto dollar = ExtendedParsedFormat<Conv::d, Conv::s>::New("%2$s %1$d");
+ ASSERT_TRUE(dollar);
+ EXPECT_EQ("{2$s:2$s}[ ]{1$d:1$d}", SummarizeParsedFormat(*dollar));
+ // with reuse
+ dollar = ExtendedParsedFormat<Conv::d, Conv::s>::New("%2$s %1$d %1$d");
+ ASSERT_TRUE(dollar);
+ EXPECT_EQ("{2$s:2$s}[ ]{1$d:1$d}[ ]{1$d:1$d}",
+ SummarizeParsedFormat(*dollar));
+}
+
+TEST_F(ParsedFormatTest, UncheckedIgnoredArgs) {
+ EXPECT_FALSE((ExtendedParsedFormat<Conv::d, Conv::s>::New("ABC")));
+ EXPECT_FALSE((ExtendedParsedFormat<Conv::d, Conv::s>::New("%dABC")));
+ EXPECT_FALSE((ExtendedParsedFormat<Conv::d, Conv::s>::New("ABC%2$s")));
+ auto f = ExtendedParsedFormat<Conv::d, Conv::s>::NewAllowIgnored("ABC");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]", SummarizeParsedFormat(*f));
+ f = ExtendedParsedFormat<Conv::d, Conv::s>::NewAllowIgnored("%dABC");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("{d:1$d}[ABC]", SummarizeParsedFormat(*f));
+ f = ExtendedParsedFormat<Conv::d, Conv::s>::NewAllowIgnored("ABC%2$s");
+ ASSERT_TRUE(f);
+ EXPECT_EQ("[ABC]{2$s:2$s}", SummarizeParsedFormat(*f));
+}
+
+TEST_F(ParsedFormatTest, UncheckedMultipleTypes) {
+ auto dx = ExtendedParsedFormat<Conv::d | Conv::x>::New("%1$d %1$x");
+ EXPECT_TRUE(dx);
+ EXPECT_EQ("{1$d:1$d}[ ]{1$x:1$x}", SummarizeParsedFormat(*dx));
+
+ dx = ExtendedParsedFormat<Conv::d | Conv::x>::New("%1$d");
+ EXPECT_TRUE(dx);
+ EXPECT_EQ("{1$d:1$d}", SummarizeParsedFormat(*dx));
+}
+
+TEST_F(ParsedFormatTest, UncheckedIncorrect) {
+ EXPECT_FALSE(ExtendedParsedFormat<Conv::d>::New(""));
+
+ EXPECT_FALSE(ExtendedParsedFormat<Conv::d>::New("ABC%dDEF%d"));
+
+ std::string format = "%sFFF%dZZZ%f";
+ EXPECT_FALSE((ExtendedParsedFormat<Conv::s, Conv::d, Conv::g>::New(format)));
+}
+
+TEST_F(ParsedFormatTest, RegressionMixPositional) {
+ EXPECT_FALSE((ExtendedParsedFormat<Conv::d, Conv::o>::New("%1$d %o")));
+}
+
+} // namespace
+} // namespace absl
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