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authorGravatar Abseil Team <absl-team@google.com>2018-06-18 13:18:53 -0700
committerGravatar Shaindel Schwartz <shaindel@google.com>2018-06-18 16:20:03 -0400
commitbd40a41cc142b36c73b881099d08a9d83f7f4780 (patch)
treea73a9bbdfdb823edee52f3b8a2973c4e240ceecc /absl/strings/numbers.cc
parentf44e1eed08cd7871de4fb7c40cae27c6f727455d (diff)
--
f28d30df5769bb832dec3ff36d2fcd2bcdf494a3 by Shaindel Schwartz <shaindel@google.com>: Internal change PiperOrigin-RevId: 201046831 -- 711715a78b7e53dfaafd4d7f08a74e76db22af88 by Mark Barolak <mbar@google.com>: Internal fix PiperOrigin-RevId: 201043684 -- 64b53edd6bf1fa48f74e7f5d33f00f80d5089147 by Shaindel Schwartz <shaindel@google.com>: Remove extra whitespace PiperOrigin-RevId: 201041989 -- 0bdd2a0b33657b688e4a04aeba9ebba47e4dc6ca by Shaindel Schwartz <shaindel@google.com>: Whitespace fix. PiperOrigin-RevId: 201034413 -- 3deb0ac296ef1b74c4789e114a8a8bf53253f26b by Shaindel Schwartz <shaindel@google.com>: Scrub build tags. No functional changes. PiperOrigin-RevId: 201032927 -- da75d0f8b73baa7e8f4e9a092bba546012ed3b71 by Alex Strelnikov <strel@google.com>: Internal change. PiperOrigin-RevId: 201026131 -- 6815d80caa19870d0c441b6b9816c68db41393a5 by Tom Manshreck <shreck@google.com>: Add documentation for our LTS snapshot branches PiperOrigin-RevId: 201025191 -- 64c3b02006f39e6a8127bbabf9ec947fb45b6504 by Greg Falcon <gfalcon@google.com>: Provide absl::from_chars for double and float types. This is a forward-compatible implementation of std::from_chars from C++17. This provides exact "round_to_nearest" conversions, and has some nice properties: * Works with string_view (it can convert numbers from non-NUL-terminated buffers) * Never allocates memory * Faster than the standard library strtod() in our toolchain * Uses integer math in its calculations, so is unaffected by floating point environment * Unaffected by C locale Also change SimpleAtod/SimpleAtoi to use this new API under the hood. PiperOrigin-RevId: 201003324 -- 542869258eb100779497c899103dc96aced52749 by Greg Falcon <gfalcon@google.com>: Internal change PiperOrigin-RevId: 200999200 -- 3aba192775c7f80e2cd7f221b0a73537823c54ea by Gennadiy Rozental <rogeeff@google.com>: Internal change PiperOrigin-RevId: 200947470 -- daf9b9feedd748d5364a4c06165b7cb7604d3e1e by Mark Barolak <mbar@google.com>: Add an absl:: qualification to a usage of base_internal::SchedulingMode outside of an absl:: namespace. PiperOrigin-RevId: 200748234 -- a8d265290a22d629f3d9bf9f872c204200bfe8c8 by Mark Barolak <mbar@google.com>: Add a missing namespace closing comment to optional.h. PiperOrigin-RevId: 200739934 -- f05af8ee1c6b864dad2df7c907d424209a3e3202 by Abseil Team <absl-team@google.com>: Internal change PiperOrigin-RevId: 200719115 GitOrigin-RevId: f28d30df5769bb832dec3ff36d2fcd2bcdf494a3 Change-Id: Ie4fa601078fd4aa57286372611f1d114fdec82c0
Diffstat (limited to 'absl/strings/numbers.cc')
-rw-r--r--absl/strings/numbers.cc86
1 files changed, 45 insertions, 41 deletions
diff --git a/absl/strings/numbers.cc b/absl/strings/numbers.cc
index 68ef7999..f842ed85 100644
--- a/absl/strings/numbers.cc
+++ b/absl/strings/numbers.cc
@@ -32,6 +32,7 @@
#include "absl/base/internal/raw_logging.h"
#include "absl/strings/ascii.h"
+#include "absl/strings/charconv.h"
#include "absl/strings/internal/bits.h"
#include "absl/strings/internal/memutil.h"
#include "absl/strings/str_cat.h"
@@ -40,51 +41,54 @@ namespace absl {
bool SimpleAtof(absl::string_view str, float* value) {
*value = 0.0;
- if (str.empty()) return false;
- char buf[32];
- std::unique_ptr<char[]> bigbuf;
- char* ptr = buf;
- if (str.size() > sizeof(buf) - 1) {
- bigbuf.reset(new char[str.size() + 1]);
- ptr = bigbuf.get();
- }
- memcpy(ptr, str.data(), str.size());
- ptr[str.size()] = '\0';
-
- char* endptr;
- *value = strtof(ptr, &endptr);
- if (endptr != ptr) {
- while (absl::ascii_isspace(*endptr)) ++endptr;
- }
- // Ignore range errors from strtod/strtof.
- // The values it returns on underflow and
- // overflow are the right fallback in a
- // robust setting.
- return *ptr != '\0' && *endptr == '\0';
+ str = StripAsciiWhitespace(str);
+ if (!str.empty() && str[0] == '+') {
+ str.remove_prefix(1);
+ }
+ auto result = absl::from_chars(str.data(), str.data() + str.size(), *value);
+ if (result.ec == std::errc::invalid_argument) {
+ return false;
+ }
+ if (result.ptr != str.data() + str.size()) {
+ // not all non-whitespace characters consumed
+ return false;
+ }
+ // from_chars() with DR 3801's current wording will return max() on
+ // overflow. SimpleAtof returns infinity instead.
+ if (result.ec == std::errc::result_out_of_range) {
+ if (*value > 1.0) {
+ *value = std::numeric_limits<float>::infinity();
+ } else if (*value < -1.0) {
+ *value = -std::numeric_limits<float>::infinity();
+ }
+ }
+ return true;
}
bool SimpleAtod(absl::string_view str, double* value) {
*value = 0.0;
- if (str.empty()) return false;
- char buf[32];
- std::unique_ptr<char[]> bigbuf;
- char* ptr = buf;
- if (str.size() > sizeof(buf) - 1) {
- bigbuf.reset(new char[str.size() + 1]);
- ptr = bigbuf.get();
- }
- memcpy(ptr, str.data(), str.size());
- ptr[str.size()] = '\0';
-
- char* endptr;
- *value = strtod(ptr, &endptr);
- if (endptr != ptr) {
- while (absl::ascii_isspace(*endptr)) ++endptr;
- }
- // Ignore range errors from strtod. The values it
- // returns on underflow and overflow are the right
- // fallback in a robust setting.
- return *ptr != '\0' && *endptr == '\0';
+ str = StripAsciiWhitespace(str);
+ if (!str.empty() && str[0] == '+') {
+ str.remove_prefix(1);
+ }
+ auto result = absl::from_chars(str.data(), str.data() + str.size(), *value);
+ if (result.ec == std::errc::invalid_argument) {
+ return false;
+ }
+ if (result.ptr != str.data() + str.size()) {
+ // not all non-whitespace characters consumed
+ return false;
+ }
+ // from_chars() with DR 3801's current wording will return max() on
+ // overflow. SimpleAtod returns infinity instead.
+ if (result.ec == std::errc::result_out_of_range) {
+ if (*value > 1.0) {
+ *value = std::numeric_limits<double>::infinity();
+ } else if (*value < -1.0) {
+ *value = -std::numeric_limits<double>::infinity();
+ }
+ }
+ return true;
}
namespace {