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-rw-r--r--absl/strings/internal/str_format/bind.h189
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diff --git a/absl/strings/internal/str_format/bind.h b/absl/strings/internal/str_format/bind.h
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+++ b/absl/strings/internal/str_format/bind.h
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+#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_