diff options
Diffstat (limited to 'absl/strings/numbers.cc')
-rw-r--r-- | absl/strings/numbers.cc | 152 |
1 files changed, 105 insertions, 47 deletions
diff --git a/absl/strings/numbers.cc b/absl/strings/numbers.cc index 2bac4adc..68c26dd6 100644 --- a/absl/strings/numbers.cc +++ b/absl/strings/numbers.cc @@ -19,8 +19,8 @@ #include <algorithm> #include <cassert> -#include <cfloat> // for DBL_DIG and FLT_DIG -#include <cmath> // for HUGE_VAL +#include <cfloat> // for DBL_DIG and FLT_DIG +#include <cmath> // for HUGE_VAL #include <cstdint> #include <cstdio> #include <cstdlib> @@ -30,16 +30,18 @@ #include <memory> #include <utility> +#include "absl/base/attributes.h" #include "absl/base/internal/bits.h" #include "absl/base/internal/raw_logging.h" #include "absl/strings/ascii.h" #include "absl/strings/charconv.h" +#include "absl/strings/escaping.h" #include "absl/strings/internal/memutil.h" #include "absl/strings/match.h" #include "absl/strings/str_cat.h" namespace absl { -inline namespace lts_2019_08_08 { +ABSL_NAMESPACE_BEGIN bool SimpleAtof(absl::string_view str, float* out) { *out = 0.0; @@ -93,43 +95,6 @@ bool SimpleAtod(absl::string_view str, double* out) { return true; } -namespace { - -// Writes a two-character representation of 'i' to 'buf'. 'i' must be in the -// range 0 <= i < 100, and buf must have space for two characters. Example: -// char buf[2]; -// PutTwoDigits(42, buf); -// // buf[0] == '4' -// // buf[1] == '2' -inline void PutTwoDigits(size_t i, char* buf) { - static const char two_ASCII_digits[100][2] = { - {'0', '0'}, {'0', '1'}, {'0', '2'}, {'0', '3'}, {'0', '4'}, - {'0', '5'}, {'0', '6'}, {'0', '7'}, {'0', '8'}, {'0', '9'}, - {'1', '0'}, {'1', '1'}, {'1', '2'}, {'1', '3'}, {'1', '4'}, - {'1', '5'}, {'1', '6'}, {'1', '7'}, {'1', '8'}, {'1', '9'}, - {'2', '0'}, {'2', '1'}, {'2', '2'}, {'2', '3'}, {'2', '4'}, - {'2', '5'}, {'2', '6'}, {'2', '7'}, {'2', '8'}, {'2', '9'}, - {'3', '0'}, {'3', '1'}, {'3', '2'}, {'3', '3'}, {'3', '4'}, - {'3', '5'}, {'3', '6'}, {'3', '7'}, {'3', '8'}, {'3', '9'}, - {'4', '0'}, {'4', '1'}, {'4', '2'}, {'4', '3'}, {'4', '4'}, - {'4', '5'}, {'4', '6'}, {'4', '7'}, {'4', '8'}, {'4', '9'}, - {'5', '0'}, {'5', '1'}, {'5', '2'}, {'5', '3'}, {'5', '4'}, - {'5', '5'}, {'5', '6'}, {'5', '7'}, {'5', '8'}, {'5', '9'}, - {'6', '0'}, {'6', '1'}, {'6', '2'}, {'6', '3'}, {'6', '4'}, - {'6', '5'}, {'6', '6'}, {'6', '7'}, {'6', '8'}, {'6', '9'}, - {'7', '0'}, {'7', '1'}, {'7', '2'}, {'7', '3'}, {'7', '4'}, - {'7', '5'}, {'7', '6'}, {'7', '7'}, {'7', '8'}, {'7', '9'}, - {'8', '0'}, {'8', '1'}, {'8', '2'}, {'8', '3'}, {'8', '4'}, - {'8', '5'}, {'8', '6'}, {'8', '7'}, {'8', '8'}, {'8', '9'}, - {'9', '0'}, {'9', '1'}, {'9', '2'}, {'9', '3'}, {'9', '4'}, - {'9', '5'}, {'9', '6'}, {'9', '7'}, {'9', '8'}, {'9', '9'} - }; - assert(i < 100); - memcpy(buf, two_ASCII_digits[i], 2); -} - -} // namespace - bool SimpleAtob(absl::string_view str, bool* out) { ABSL_RAW_CHECK(out != nullptr, "Output pointer must not be nullptr."); if (EqualsIgnoreCase(str, "true") || EqualsIgnoreCase(str, "t") || @@ -496,13 +461,13 @@ static ExpDigits SplitToSix(const double value) { int two_digits = dddddd / 10000; dddddd -= two_digits * 10000; - PutTwoDigits(two_digits, &exp_dig.digits[0]); + numbers_internal::PutTwoDigits(two_digits, &exp_dig.digits[0]); two_digits = dddddd / 100; dddddd -= two_digits * 100; - PutTwoDigits(two_digits, &exp_dig.digits[2]); + numbers_internal::PutTwoDigits(two_digits, &exp_dig.digits[2]); - PutTwoDigits(dddddd, &exp_dig.digits[4]); + numbers_internal::PutTwoDigits(dddddd, &exp_dig.digits[4]); return exp_dig; } @@ -755,8 +720,8 @@ inline bool safe_parse_sign_and_base(absl::string_view* text /*inout*/, // commonly used bases. template <typename IntType> struct LookupTables { - static const IntType kVmaxOverBase[]; - static const IntType kVminOverBase[]; + ABSL_CONST_INIT static const IntType kVmaxOverBase[]; + ABSL_CONST_INIT static const IntType kVminOverBase[]; }; // An array initializer macro for X/base where base in [0, 36]. @@ -771,6 +736,49 @@ struct LookupTables { X / 35, X / 36, \ } +// uint128& operator/=(uint128) is not constexpr, so hardcode the resulting +// array to avoid a static initializer. +template <> +const uint128 LookupTables<uint128>::kVmaxOverBase[] = { + 0, + 0, + MakeUint128(9223372036854775807u, 18446744073709551615u), + MakeUint128(6148914691236517205u, 6148914691236517205u), + MakeUint128(4611686018427387903u, 18446744073709551615u), + MakeUint128(3689348814741910323u, 3689348814741910323u), + MakeUint128(3074457345618258602u, 12297829382473034410u), + MakeUint128(2635249153387078802u, 5270498306774157604u), + MakeUint128(2305843009213693951u, 18446744073709551615u), + MakeUint128(2049638230412172401u, 14347467612885206812u), + MakeUint128(1844674407370955161u, 11068046444225730969u), + MakeUint128(1676976733973595601u, 8384883669867978007u), + MakeUint128(1537228672809129301u, 6148914691236517205u), + MakeUint128(1418980313362273201u, 4256940940086819603u), + MakeUint128(1317624576693539401u, 2635249153387078802u), + MakeUint128(1229782938247303441u, 1229782938247303441u), + MakeUint128(1152921504606846975u, 18446744073709551615u), + MakeUint128(1085102592571150095u, 1085102592571150095u), + MakeUint128(1024819115206086200u, 16397105843297379214u), + MakeUint128(970881267037344821u, 16504981539634861972u), + MakeUint128(922337203685477580u, 14757395258967641292u), + MakeUint128(878416384462359600u, 14054662151397753612u), + MakeUint128(838488366986797800u, 13415813871788764811u), + MakeUint128(802032351030850070u, 4812194106185100421u), + MakeUint128(768614336404564650u, 12297829382473034410u), + MakeUint128(737869762948382064u, 11805916207174113034u), + MakeUint128(709490156681136600u, 11351842506898185609u), + MakeUint128(683212743470724133u, 17080318586768103348u), + MakeUint128(658812288346769700u, 10540996613548315209u), + MakeUint128(636094623231363848u, 15266270957552732371u), + MakeUint128(614891469123651720u, 9838263505978427528u), + MakeUint128(595056260442243600u, 9520900167075897608u), + MakeUint128(576460752303423487u, 18446744073709551615u), + MakeUint128(558992244657865200u, 8943875914525843207u), + MakeUint128(542551296285575047u, 9765923333140350855u), + MakeUint128(527049830677415760u, 8432797290838652167u), + MakeUint128(512409557603043100u, 8198552921648689607u), +}; + template <typename IntType> const IntType LookupTables<IntType>::kVmaxOverBase[] = X_OVER_BASE_INITIALIZER(std::numeric_limits<IntType>::max()); @@ -790,6 +798,8 @@ inline bool safe_parse_positive_int(absl::string_view text, int base, assert(base >= 0); assert(vmax >= static_cast<IntType>(base)); const IntType vmax_over_base = LookupTables<IntType>::kVmaxOverBase[base]; + assert(base < 2 || + std::numeric_limits<IntType>::max() / base == vmax_over_base); const char* start = text.data(); const char* end = start + text.size(); // loop over digits @@ -823,6 +833,8 @@ inline bool safe_parse_negative_int(absl::string_view text, int base, assert(vmin < 0); assert(vmin <= 0 - base); IntType vmin_over_base = LookupTables<IntType>::kVminOverBase[base]; + assert(base < 2 || + std::numeric_limits<IntType>::min() / base == vmin_over_base); // 2003 c++ standard [expr.mul] // "... the sign of the remainder is implementation-defined." // Although (vmin/base)*base + vmin%base is always vmin. @@ -886,6 +898,48 @@ inline bool safe_uint_internal(absl::string_view text, IntType* value_p, } // anonymous namespace namespace numbers_internal { + +// Digit conversion. +ABSL_CONST_INIT ABSL_DLL const char kHexChar[] = + "0123456789abcdef"; + +ABSL_CONST_INIT ABSL_DLL const char kHexTable[513] = + "000102030405060708090a0b0c0d0e0f" + "101112131415161718191a1b1c1d1e1f" + "202122232425262728292a2b2c2d2e2f" + "303132333435363738393a3b3c3d3e3f" + "404142434445464748494a4b4c4d4e4f" + "505152535455565758595a5b5c5d5e5f" + "606162636465666768696a6b6c6d6e6f" + "707172737475767778797a7b7c7d7e7f" + "808182838485868788898a8b8c8d8e8f" + "909192939495969798999a9b9c9d9e9f" + "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf" + "b0b1b2b3b4b5b6b7b8b9babbbcbdbebf" + "c0c1c2c3c4c5c6c7c8c9cacbcccdcecf" + "d0d1d2d3d4d5d6d7d8d9dadbdcdddedf" + "e0e1e2e3e4e5e6e7e8e9eaebecedeeef" + "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff"; + +ABSL_CONST_INIT ABSL_DLL const char two_ASCII_digits[100][2] = { + {'0', '0'}, {'0', '1'}, {'0', '2'}, {'0', '3'}, {'0', '4'}, {'0', '5'}, + {'0', '6'}, {'0', '7'}, {'0', '8'}, {'0', '9'}, {'1', '0'}, {'1', '1'}, + {'1', '2'}, {'1', '3'}, {'1', '4'}, {'1', '5'}, {'1', '6'}, {'1', '7'}, + {'1', '8'}, {'1', '9'}, {'2', '0'}, {'2', '1'}, {'2', '2'}, {'2', '3'}, + {'2', '4'}, {'2', '5'}, {'2', '6'}, {'2', '7'}, {'2', '8'}, {'2', '9'}, + {'3', '0'}, {'3', '1'}, {'3', '2'}, {'3', '3'}, {'3', '4'}, {'3', '5'}, + {'3', '6'}, {'3', '7'}, {'3', '8'}, {'3', '9'}, {'4', '0'}, {'4', '1'}, + {'4', '2'}, {'4', '3'}, {'4', '4'}, {'4', '5'}, {'4', '6'}, {'4', '7'}, + {'4', '8'}, {'4', '9'}, {'5', '0'}, {'5', '1'}, {'5', '2'}, {'5', '3'}, + {'5', '4'}, {'5', '5'}, {'5', '6'}, {'5', '7'}, {'5', '8'}, {'5', '9'}, + {'6', '0'}, {'6', '1'}, {'6', '2'}, {'6', '3'}, {'6', '4'}, {'6', '5'}, + {'6', '6'}, {'6', '7'}, {'6', '8'}, {'6', '9'}, {'7', '0'}, {'7', '1'}, + {'7', '2'}, {'7', '3'}, {'7', '4'}, {'7', '5'}, {'7', '6'}, {'7', '7'}, + {'7', '8'}, {'7', '9'}, {'8', '0'}, {'8', '1'}, {'8', '2'}, {'8', '3'}, + {'8', '4'}, {'8', '5'}, {'8', '6'}, {'8', '7'}, {'8', '8'}, {'8', '9'}, + {'9', '0'}, {'9', '1'}, {'9', '2'}, {'9', '3'}, {'9', '4'}, {'9', '5'}, + {'9', '6'}, {'9', '7'}, {'9', '8'}, {'9', '9'}}; + bool safe_strto32_base(absl::string_view text, int32_t* value, int base) { return safe_int_internal<int32_t>(text, value, base); } @@ -901,7 +955,11 @@ bool safe_strtou32_base(absl::string_view text, uint32_t* value, int base) { bool safe_strtou64_base(absl::string_view text, uint64_t* value, int base) { return safe_uint_internal<uint64_t>(text, value, base); } -} // namespace numbers_internal -} // inline namespace lts_2019_08_08 +bool safe_strtou128_base(absl::string_view text, uint128* value, int base) { + return safe_uint_internal<absl::uint128>(text, value, base); +} + +} // namespace numbers_internal +ABSL_NAMESPACE_END } // namespace absl |