From b56cbdd23834a65682c0b46f367f8679e83bc894 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Fri, 18 Sep 2020 15:55:15 -0700 Subject: Abseil LTS 20200923 What's New: * `absl::StatusOr` has been released. See our [blog post](https://abseil.io/blog/2020-091021-status) for more information. * Abseil Flags reflection interfaces have been released. * Abseil Flags memory usage has been significantly optimized. * Abseil now supports a "hardened" build mode. This build mode enables runtime checks that guard against programming errors that may lead to security vulnerabilities. Notable Fixes: * Sanitizer dynamic annotations like `AnnotateRWLockCreate` that are also defined by the compiler sanitizer implementation are no longer also defined by Abseil. * Sanitizer macros are now prefixed with `ABSL_` to avoid naming collisions. * Sanitizer usage is now automatically detected and no longer requires macros like `ADDRESS_SANITIZER` to be defined on the command line. Breaking Changes: * Abseil no longer contains a `dynamic_annotations` library. Users using a supported build system (Bazel or CMake) are unaffected by this, but users manually specifying link libraries may get an error about a missing linker input. Baseline: 7680a5f8efe32de4753baadbd63e74e59d95bac1 Cherry picks: None --- absl/time/duration.cc | 149 ++++++++++++++++++++++++++++++-------------------- 1 file changed, 90 insertions(+), 59 deletions(-) (limited to 'absl/time/duration.cc') diff --git a/absl/time/duration.cc b/absl/time/duration.cc index b1af8406..952cc093 100644 --- a/absl/time/duration.cc +++ b/absl/time/duration.cc @@ -67,7 +67,10 @@ #include #include "absl/base/casts.h" +#include "absl/base/macros.h" #include "absl/numeric/int128.h" +#include "absl/strings/string_view.h" +#include "absl/strings/strip.h" #include "absl/time/time.h" namespace absl { @@ -708,16 +711,17 @@ char* Format64(char* ep, int width, int64_t v) { // fractional digits, because it is in the noise of what a Duration can // represent. struct DisplayUnit { - const char* abbr; + absl::string_view abbr; int prec; double pow10; }; -const DisplayUnit kDisplayNano = {"ns", 2, 1e2}; -const DisplayUnit kDisplayMicro = {"us", 5, 1e5}; -const DisplayUnit kDisplayMilli = {"ms", 8, 1e8}; -const DisplayUnit kDisplaySec = {"s", 11, 1e11}; -const DisplayUnit kDisplayMin = {"m", -1, 0.0}; // prec ignored -const DisplayUnit kDisplayHour = {"h", -1, 0.0}; // prec ignored +ABSL_CONST_INIT const DisplayUnit kDisplayNano = {"ns", 2, 1e2}; +ABSL_CONST_INIT const DisplayUnit kDisplayMicro = {"us", 5, 1e5}; +ABSL_CONST_INIT const DisplayUnit kDisplayMilli = {"ms", 8, 1e8}; +ABSL_CONST_INIT const DisplayUnit kDisplaySec = {"s", 11, 1e11}; +ABSL_CONST_INIT const DisplayUnit kDisplayMin = {"m", -1, 0.0}; // prec ignored +ABSL_CONST_INIT const DisplayUnit kDisplayHour = {"h", -1, + 0.0}; // prec ignored void AppendNumberUnit(std::string* out, int64_t n, DisplayUnit unit) { char buf[sizeof("2562047788015216")]; // hours in max duration @@ -725,16 +729,16 @@ void AppendNumberUnit(std::string* out, int64_t n, DisplayUnit unit) { char* bp = Format64(ep, 0, n); if (*bp != '0' || bp + 1 != ep) { out->append(bp, ep - bp); - out->append(unit.abbr); + out->append(unit.abbr.data(), unit.abbr.size()); } } // Note: unit.prec is limited to double's digits10 value (typically 15) so it // always fits in buf[]. void AppendNumberUnit(std::string* out, double n, DisplayUnit unit) { - const int buf_size = std::numeric_limits::digits10; - const int prec = std::min(buf_size, unit.prec); - char buf[buf_size]; // also large enough to hold integer part + constexpr int kBufferSize = std::numeric_limits::digits10; + const int prec = std::min(kBufferSize, unit.prec); + char buf[kBufferSize]; // also large enough to hold integer part char* ep = buf + sizeof(buf); double d = 0; int64_t frac_part = Round(std::modf(n, &d) * unit.pow10); @@ -748,7 +752,7 @@ void AppendNumberUnit(std::string* out, double n, DisplayUnit unit) { while (ep[-1] == '0') --ep; out->append(bp, ep - bp); } - out->append(unit.abbr); + out->append(unit.abbr.data(), unit.abbr.size()); } } @@ -800,23 +804,27 @@ namespace { // A helper for ParseDuration() that parses a leading number from the given // string and stores the result in *int_part/*frac_part/*frac_scale. The // given string pointer is modified to point to the first unconsumed char. -bool ConsumeDurationNumber(const char** dpp, int64_t* int_part, +bool ConsumeDurationNumber(const char** dpp, const char* ep, int64_t* int_part, int64_t* frac_part, int64_t* frac_scale) { *int_part = 0; *frac_part = 0; *frac_scale = 1; // invariant: *frac_part < *frac_scale const char* start = *dpp; - for (; std::isdigit(**dpp); *dpp += 1) { + for (; *dpp != ep; *dpp += 1) { const int d = **dpp - '0'; // contiguous digits + if (d < 0 || 10 <= d) break; + if (*int_part > kint64max / 10) return false; *int_part *= 10; if (*int_part > kint64max - d) return false; *int_part += d; } const bool int_part_empty = (*dpp == start); - if (**dpp != '.') return !int_part_empty; - for (*dpp += 1; std::isdigit(**dpp); *dpp += 1) { + if (*dpp == ep || **dpp != '.') return !int_part_empty; + + for (*dpp += 1; *dpp != ep; *dpp += 1) { const int d = **dpp - '0'; // contiguous digits + if (d < 0 || 10 <= d) break; if (*frac_scale <= kint64max / 10) { *frac_part *= 10; *frac_part += d; @@ -830,32 +838,56 @@ bool ConsumeDurationNumber(const char** dpp, int64_t* int_part, // ns, us, ms, s, m, h) from the given string and stores the resulting unit // in "*unit". The given string pointer is modified to point to the first // unconsumed char. -bool ConsumeDurationUnit(const char** start, Duration* unit) { - const char *s = *start; - bool ok = true; - if (strncmp(s, "ns", 2) == 0) { - s += 2; - *unit = Nanoseconds(1); - } else if (strncmp(s, "us", 2) == 0) { - s += 2; - *unit = Microseconds(1); - } else if (strncmp(s, "ms", 2) == 0) { - s += 2; - *unit = Milliseconds(1); - } else if (strncmp(s, "s", 1) == 0) { - s += 1; - *unit = Seconds(1); - } else if (strncmp(s, "m", 1) == 0) { - s += 1; - *unit = Minutes(1); - } else if (strncmp(s, "h", 1) == 0) { - s += 1; - *unit = Hours(1); - } else { - ok = false; +bool ConsumeDurationUnit(const char** start, const char* end, Duration* unit) { + size_t size = end - *start; + switch (size) { + case 0: + return false; + default: + switch (**start) { + case 'n': + if (*(*start + 1) == 's') { + *start += 2; + *unit = Nanoseconds(1); + return true; + } + break; + case 'u': + if (*(*start + 1) == 's') { + *start += 2; + *unit = Microseconds(1); + return true; + } + break; + case 'm': + if (*(*start + 1) == 's') { + *start += 2; + *unit = Milliseconds(1); + return true; + } + break; + default: + break; + } + ABSL_FALLTHROUGH_INTENDED; + case 1: + switch (**start) { + case 's': + *unit = Seconds(1); + *start += 1; + return true; + case 'm': + *unit = Minutes(1); + *start += 1; + return true; + case 'h': + *unit = Hours(1); + *start += 1; + return true; + default: + return false; + } } - *start = s; - return ok; } } // namespace @@ -865,39 +897,38 @@ bool ConsumeDurationUnit(const char** start, Duration* unit) { // a possibly signed sequence of decimal numbers, each with optional // fraction and a unit suffix, such as "300ms", "-1.5h" or "2h45m". // Valid time units are "ns", "us" "ms", "s", "m", "h". -bool ParseDuration(const std::string& dur_string, Duration* d) { - const char* start = dur_string.c_str(); +bool ParseDuration(absl::string_view dur_sv, Duration* d) { int sign = 1; - - if (*start == '-' || *start == '+') { - sign = *start == '-' ? -1 : 1; - ++start; - } - - // Can't parse a duration from an empty std::string. - if (*start == '\0') { - return false; + if (absl::ConsumePrefix(&dur_sv, "-")) { + sign = -1; + } else { + absl::ConsumePrefix(&dur_sv, "+"); } + if (dur_sv.empty()) return false; - // Special case for a std::string of "0". - if (*start == '0' && *(start + 1) == '\0') { + // Special case for a string of "0". + if (dur_sv == "0") { *d = ZeroDuration(); return true; } - if (strcmp(start, "inf") == 0) { + if (dur_sv == "inf") { *d = sign * InfiniteDuration(); return true; } + const char* start = dur_sv.data(); + const char* end = start + dur_sv.size(); + Duration dur; - while (*start != '\0') { + while (start != end) { int64_t int_part; int64_t frac_part; int64_t frac_scale; Duration unit; - if (!ConsumeDurationNumber(&start, &int_part, &frac_part, &frac_scale) || - !ConsumeDurationUnit(&start, &unit)) { + if (!ConsumeDurationNumber(&start, end, &int_part, &frac_part, + &frac_scale) || + !ConsumeDurationUnit(&start, end, &unit)) { return false; } if (int_part != 0) dur += sign * int_part * unit; @@ -908,7 +939,7 @@ bool ParseDuration(const std::string& dur_string, Duration* d) { } bool AbslParseFlag(absl::string_view text, Duration* dst, std::string*) { - return ParseDuration(std::string(text), dst); + return ParseDuration(text, dst); } std::string AbslUnparseFlag(Duration d) { return FormatDuration(d); } -- cgit v1.2.3