fmtlegacy/include/fmt/chrono.h
2021-05-24 14:09:19 -07:00

1295 lines
40 KiB
C++

// Formatting library for C++ - chrono support
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
#ifndef FMT_CHRONO_H_
#define FMT_CHRONO_H_
#include <algorithm>
#include <chrono>
#include <ctime>
#include <locale>
#include <sstream>
#include "format.h"
FMT_BEGIN_NAMESPACE
// Enable safe chrono durations, unless explicitly disabled.
#ifndef FMT_SAFE_DURATION_CAST
# define FMT_SAFE_DURATION_CAST 1
#endif
#if FMT_SAFE_DURATION_CAST
// For conversion between std::chrono::durations without undefined
// behaviour or erroneous results.
// This is a stripped down version of duration_cast, for inclusion in fmt.
// See https://github.com/pauldreik/safe_duration_cast
//
// Copyright Paul Dreik 2019
namespace safe_duration_cast {
template <typename To, typename From,
FMT_ENABLE_IF(!std::is_same<From, To>::value &&
std::numeric_limits<From>::is_signed ==
std::numeric_limits<To>::is_signed)>
FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
ec = 0;
using F = std::numeric_limits<From>;
using T = std::numeric_limits<To>;
static_assert(F::is_integer, "From must be integral");
static_assert(T::is_integer, "To must be integral");
// A and B are both signed, or both unsigned.
if (F::digits <= T::digits) {
// From fits in To without any problem.
} else {
// From does not always fit in To, resort to a dynamic check.
if (from < (T::min)() || from > (T::max)()) {
// outside range.
ec = 1;
return {};
}
}
return static_cast<To>(from);
}
/**
* converts From to To, without loss. If the dynamic value of from
* can't be converted to To without loss, ec is set.
*/
template <typename To, typename From,
FMT_ENABLE_IF(!std::is_same<From, To>::value &&
std::numeric_limits<From>::is_signed !=
std::numeric_limits<To>::is_signed)>
FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
ec = 0;
using F = std::numeric_limits<From>;
using T = std::numeric_limits<To>;
static_assert(F::is_integer, "From must be integral");
static_assert(T::is_integer, "To must be integral");
if (detail::const_check(F::is_signed && !T::is_signed)) {
// From may be negative, not allowed!
if (fmt::detail::is_negative(from)) {
ec = 1;
return {};
}
// From is positive. Can it always fit in To?
if (F::digits > T::digits &&
from > static_cast<From>(detail::max_value<To>())) {
ec = 1;
return {};
}
}
if (!F::is_signed && T::is_signed && F::digits >= T::digits &&
from > static_cast<From>(detail::max_value<To>())) {
ec = 1;
return {};
}
return static_cast<To>(from); // Lossless conversion.
}
template <typename To, typename From,
FMT_ENABLE_IF(std::is_same<From, To>::value)>
FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
ec = 0;
return from;
} // function
// clang-format off
/**
* converts From to To if possible, otherwise ec is set.
*
* input | output
* ---------------------------------|---------------
* NaN | NaN
* Inf | Inf
* normal, fits in output | converted (possibly lossy)
* normal, does not fit in output | ec is set
* subnormal | best effort
* -Inf | -Inf
*/
// clang-format on
template <typename To, typename From,
FMT_ENABLE_IF(!std::is_same<From, To>::value)>
FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
ec = 0;
using T = std::numeric_limits<To>;
static_assert(std::is_floating_point<From>::value, "From must be floating");
static_assert(std::is_floating_point<To>::value, "To must be floating");
// catch the only happy case
if (std::isfinite(from)) {
if (from >= T::lowest() && from <= (T::max)()) {
return static_cast<To>(from);
}
// not within range.
ec = 1;
return {};
}
// nan and inf will be preserved
return static_cast<To>(from);
} // function
template <typename To, typename From,
FMT_ENABLE_IF(std::is_same<From, To>::value)>
FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
ec = 0;
static_assert(std::is_floating_point<From>::value, "From must be floating");
return from;
}
/**
* safe duration cast between integral durations
*/
template <typename To, typename FromRep, typename FromPeriod,
FMT_ENABLE_IF(std::is_integral<FromRep>::value),
FMT_ENABLE_IF(std::is_integral<typename To::rep>::value)>
To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
int& ec) {
using From = std::chrono::duration<FromRep, FromPeriod>;
ec = 0;
// the basic idea is that we need to convert from count() in the from type
// to count() in the To type, by multiplying it with this:
struct Factor
: std::ratio_divide<typename From::period, typename To::period> {};
static_assert(Factor::num > 0, "num must be positive");
static_assert(Factor::den > 0, "den must be positive");
// the conversion is like this: multiply from.count() with Factor::num
// /Factor::den and convert it to To::rep, all this without
// overflow/underflow. let's start by finding a suitable type that can hold
// both To, From and Factor::num
using IntermediateRep =
typename std::common_type<typename From::rep, typename To::rep,
decltype(Factor::num)>::type;
// safe conversion to IntermediateRep
IntermediateRep count =
lossless_integral_conversion<IntermediateRep>(from.count(), ec);
if (ec) return {};
// multiply with Factor::num without overflow or underflow
if (detail::const_check(Factor::num != 1)) {
const auto max1 = detail::max_value<IntermediateRep>() / Factor::num;
if (count > max1) {
ec = 1;
return {};
}
const auto min1 =
(std::numeric_limits<IntermediateRep>::min)() / Factor::num;
if (count < min1) {
ec = 1;
return {};
}
count *= Factor::num;
}
if (detail::const_check(Factor::den != 1)) count /= Factor::den;
auto tocount = lossless_integral_conversion<typename To::rep>(count, ec);
return ec ? To() : To(tocount);
}
/**
* safe duration_cast between floating point durations
*/
template <typename To, typename FromRep, typename FromPeriod,
FMT_ENABLE_IF(std::is_floating_point<FromRep>::value),
FMT_ENABLE_IF(std::is_floating_point<typename To::rep>::value)>
To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
int& ec) {
using From = std::chrono::duration<FromRep, FromPeriod>;
ec = 0;
if (std::isnan(from.count())) {
// nan in, gives nan out. easy.
return To{std::numeric_limits<typename To::rep>::quiet_NaN()};
}
// maybe we should also check if from is denormal, and decide what to do about
// it.
// +-inf should be preserved.
if (std::isinf(from.count())) {
return To{from.count()};
}
// the basic idea is that we need to convert from count() in the from type
// to count() in the To type, by multiplying it with this:
struct Factor
: std::ratio_divide<typename From::period, typename To::period> {};
static_assert(Factor::num > 0, "num must be positive");
static_assert(Factor::den > 0, "den must be positive");
// the conversion is like this: multiply from.count() with Factor::num
// /Factor::den and convert it to To::rep, all this without
// overflow/underflow. let's start by finding a suitable type that can hold
// both To, From and Factor::num
using IntermediateRep =
typename std::common_type<typename From::rep, typename To::rep,
decltype(Factor::num)>::type;
// force conversion of From::rep -> IntermediateRep to be safe,
// even if it will never happen be narrowing in this context.
IntermediateRep count =
safe_float_conversion<IntermediateRep>(from.count(), ec);
if (ec) {
return {};
}
// multiply with Factor::num without overflow or underflow
if (Factor::num != 1) {
constexpr auto max1 = detail::max_value<IntermediateRep>() /
static_cast<IntermediateRep>(Factor::num);
if (count > max1) {
ec = 1;
return {};
}
constexpr auto min1 = std::numeric_limits<IntermediateRep>::lowest() /
static_cast<IntermediateRep>(Factor::num);
if (count < min1) {
ec = 1;
return {};
}
count *= static_cast<IntermediateRep>(Factor::num);
}
// this can't go wrong, right? den>0 is checked earlier.
if (Factor::den != 1) {
using common_t = typename std::common_type<IntermediateRep, intmax_t>::type;
count /= static_cast<common_t>(Factor::den);
}
// convert to the to type, safely
using ToRep = typename To::rep;
const ToRep tocount = safe_float_conversion<ToRep>(count, ec);
if (ec) {
return {};
}
return To{tocount};
}
} // namespace safe_duration_cast
#endif
// Prevents expansion of a preceding token as a function-style macro.
// Usage: f FMT_NOMACRO()
#define FMT_NOMACRO
namespace detail {
template <typename T = void> struct null {};
inline null<> localtime_r FMT_NOMACRO(...) { return null<>(); }
inline null<> localtime_s(...) { return null<>(); }
inline null<> gmtime_r(...) { return null<>(); }
inline null<> gmtime_s(...) { return null<>(); }
} // namespace detail
FMT_MODULE_EXPORT_BEGIN
/**
Converts given time since epoch as ``std::time_t`` value into calendar time,
expressed in local time. Unlike ``std::localtime``, this function is
thread-safe on most platforms.
*/
inline std::tm localtime(std::time_t time) {
struct dispatcher {
std::time_t time_;
std::tm tm_;
dispatcher(std::time_t t) : time_(t) {}
bool run() {
using namespace fmt::detail;
return handle(localtime_r(&time_, &tm_));
}
bool handle(std::tm* tm) { return tm != nullptr; }
bool handle(detail::null<>) {
using namespace fmt::detail;
return fallback(localtime_s(&tm_, &time_));
}
bool fallback(int res) { return res == 0; }
#if !FMT_MSC_VER
bool fallback(detail::null<>) {
using namespace fmt::detail;
std::tm* tm = std::localtime(&time_);
if (tm) tm_ = *tm;
return tm != nullptr;
}
#endif
};
dispatcher lt(time);
// Too big time values may be unsupported.
if (!lt.run()) FMT_THROW(format_error("time_t value out of range"));
return lt.tm_;
}
inline std::tm localtime(
std::chrono::time_point<std::chrono::system_clock> time_point) {
return localtime(std::chrono::system_clock::to_time_t(time_point));
}
/**
Converts given time since epoch as ``std::time_t`` value into calendar time,
expressed in Coordinated Universal Time (UTC). Unlike ``std::gmtime``, this
function is thread-safe on most platforms.
*/
inline std::tm gmtime(std::time_t time) {
struct dispatcher {
std::time_t time_;
std::tm tm_;
dispatcher(std::time_t t) : time_(t) {}
bool run() {
using namespace fmt::detail;
return handle(gmtime_r(&time_, &tm_));
}
bool handle(std::tm* tm) { return tm != nullptr; }
bool handle(detail::null<>) {
using namespace fmt::detail;
return fallback(gmtime_s(&tm_, &time_));
}
bool fallback(int res) { return res == 0; }
#if !FMT_MSC_VER
bool fallback(detail::null<>) {
std::tm* tm = std::gmtime(&time_);
if (tm) tm_ = *tm;
return tm != nullptr;
}
#endif
};
dispatcher gt(time);
// Too big time values may be unsupported.
if (!gt.run()) FMT_THROW(format_error("time_t value out of range"));
return gt.tm_;
}
inline std::tm gmtime(
std::chrono::time_point<std::chrono::system_clock> time_point) {
return gmtime(std::chrono::system_clock::to_time_t(time_point));
}
FMT_BEGIN_DETAIL_NAMESPACE
inline size_t strftime(char* str, size_t count, const char* format,
const std::tm* time) {
// Assign to a pointer to suppress GCCs -Wformat-nonliteral
// First assign the nullptr to suppress -Wsuggest-attribute=format
std::size_t (*strftime)(char*, std::size_t, const char*, const std::tm*) =
nullptr;
strftime = std::strftime;
return strftime(str, count, format, time);
}
inline size_t strftime(wchar_t* str, size_t count, const wchar_t* format,
const std::tm* time) {
// See above
std::size_t (*wcsftime)(wchar_t*, std::size_t, const wchar_t*,
const std::tm*) = nullptr;
wcsftime = std::wcsftime;
return wcsftime(str, count, format, time);
}
FMT_END_DETAIL_NAMESPACE
template <typename Char, typename Duration>
struct formatter<std::chrono::time_point<std::chrono::system_clock, Duration>,
Char> : formatter<std::tm, Char> {
template <typename FormatContext>
auto format(std::chrono::time_point<std::chrono::system_clock> val,
FormatContext& ctx) -> decltype(ctx.out()) {
std::tm time = localtime(val);
return formatter<std::tm, Char>::format(time, ctx);
}
};
template <typename Char> struct formatter<std::tm, Char> {
template <typename ParseContext>
FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
auto it = ctx.begin();
if (it != ctx.end() && *it == ':') ++it;
auto end = it;
while (end != ctx.end() && *end != '}') ++end;
specs = {it, detail::to_unsigned(end - it)};
return end;
}
template <typename FormatContext>
auto format(const std::tm& tm, FormatContext& ctx) const
-> decltype(ctx.out()) {
basic_memory_buffer<Char> tm_format;
tm_format.append(specs.begin(), specs.end());
// By appending an extra space we can distinguish an empty result that
// indicates insufficient buffer size from a guaranteed non-empty result
// https://github.com/fmtlib/fmt/issues/2238
tm_format.push_back(' ');
tm_format.push_back('\0');
basic_memory_buffer<Char> buf;
size_t start = buf.size();
for (;;) {
size_t size = buf.capacity() - start;
size_t count = detail::strftime(&buf[start], size, &tm_format[0], &tm);
if (count != 0) {
buf.resize(start + count);
break;
}
const size_t MIN_GROWTH = 10;
buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
}
// Remove the extra space.
return std::copy(buf.begin(), buf.end() - 1, ctx.out());
}
basic_string_view<Char> specs;
};
FMT_BEGIN_DETAIL_NAMESPACE
template <typename Period> FMT_CONSTEXPR const char* get_units() {
return nullptr;
}
template <> FMT_CONSTEXPR inline const char* get_units<std::atto>() {
return "as";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::femto>() {
return "fs";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::pico>() {
return "ps";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::nano>() {
return "ns";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::micro>() {
return "µs";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::milli>() {
return "ms";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::centi>() {
return "cs";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::deci>() {
return "ds";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::ratio<1>>() {
return "s";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::deca>() {
return "das";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::hecto>() {
return "hs";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::kilo>() {
return "ks";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::mega>() {
return "Ms";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::giga>() {
return "Gs";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::tera>() {
return "Ts";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::peta>() {
return "Ps";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::exa>() {
return "Es";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::ratio<60>>() {
return "m";
}
template <> FMT_CONSTEXPR inline const char* get_units<std::ratio<3600>>() {
return "h";
}
enum class numeric_system {
standard,
// Alternative numeric system, e.g. 十二 instead of 12 in ja_JP locale.
alternative
};
// Parses a put_time-like format string and invokes handler actions.
template <typename Char, typename Handler>
FMT_CONSTEXPR const Char* parse_chrono_format(const Char* begin,
const Char* end,
Handler&& handler) {
auto ptr = begin;
while (ptr != end) {
auto c = *ptr;
if (c == '}') break;
if (c != '%') {
++ptr;
continue;
}
if (begin != ptr) handler.on_text(begin, ptr);
++ptr; // consume '%'
if (ptr == end) FMT_THROW(format_error("invalid format"));
c = *ptr++;
switch (c) {
case '%':
handler.on_text(ptr - 1, ptr);
break;
case 'n': {
const Char newline[] = {'\n'};
handler.on_text(newline, newline + 1);
break;
}
case 't': {
const Char tab[] = {'\t'};
handler.on_text(tab, tab + 1);
break;
}
// Day of the week:
case 'a':
handler.on_abbr_weekday();
break;
case 'A':
handler.on_full_weekday();
break;
case 'w':
handler.on_dec0_weekday(numeric_system::standard);
break;
case 'u':
handler.on_dec1_weekday(numeric_system::standard);
break;
// Month:
case 'b':
handler.on_abbr_month();
break;
case 'B':
handler.on_full_month();
break;
// Hour, minute, second:
case 'H':
handler.on_24_hour(numeric_system::standard);
break;
case 'I':
handler.on_12_hour(numeric_system::standard);
break;
case 'M':
handler.on_minute(numeric_system::standard);
break;
case 'S':
handler.on_second(numeric_system::standard);
break;
// Other:
case 'c':
handler.on_datetime(numeric_system::standard);
break;
case 'x':
handler.on_loc_date(numeric_system::standard);
break;
case 'X':
handler.on_loc_time(numeric_system::standard);
break;
case 'D':
handler.on_us_date();
break;
case 'F':
handler.on_iso_date();
break;
case 'r':
handler.on_12_hour_time();
break;
case 'R':
handler.on_24_hour_time();
break;
case 'T':
handler.on_iso_time();
break;
case 'p':
handler.on_am_pm();
break;
case 'Q':
handler.on_duration_value();
break;
case 'q':
handler.on_duration_unit();
break;
case 'z':
handler.on_utc_offset();
break;
case 'Z':
handler.on_tz_name();
break;
// Alternative representation:
case 'E': {
if (ptr == end) FMT_THROW(format_error("invalid format"));
c = *ptr++;
switch (c) {
case 'c':
handler.on_datetime(numeric_system::alternative);
break;
case 'x':
handler.on_loc_date(numeric_system::alternative);
break;
case 'X':
handler.on_loc_time(numeric_system::alternative);
break;
default:
FMT_THROW(format_error("invalid format"));
}
break;
}
case 'O':
if (ptr == end) FMT_THROW(format_error("invalid format"));
c = *ptr++;
switch (c) {
case 'w':
handler.on_dec0_weekday(numeric_system::alternative);
break;
case 'u':
handler.on_dec1_weekday(numeric_system::alternative);
break;
case 'H':
handler.on_24_hour(numeric_system::alternative);
break;
case 'I':
handler.on_12_hour(numeric_system::alternative);
break;
case 'M':
handler.on_minute(numeric_system::alternative);
break;
case 'S':
handler.on_second(numeric_system::alternative);
break;
default:
FMT_THROW(format_error("invalid format"));
}
break;
default:
FMT_THROW(format_error("invalid format"));
}
begin = ptr;
}
if (begin != ptr) handler.on_text(begin, ptr);
return ptr;
}
template <typename Derived> struct null_chrono_spec_handler {
FMT_CONSTEXPR void unsupported() {
static_cast<Derived*>(this)->unsupported();
}
FMT_CONSTEXPR void on_abbr_weekday() { unsupported(); }
FMT_CONSTEXPR void on_full_weekday() { unsupported(); }
FMT_CONSTEXPR void on_dec0_weekday(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_dec1_weekday(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_abbr_month() { unsupported(); }
FMT_CONSTEXPR void on_full_month() { unsupported(); }
FMT_CONSTEXPR void on_24_hour(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_12_hour(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_minute(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_second(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_datetime(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_loc_date(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_loc_time(numeric_system) { unsupported(); }
FMT_CONSTEXPR void on_us_date() { unsupported(); }
FMT_CONSTEXPR void on_iso_date() { unsupported(); }
FMT_CONSTEXPR void on_12_hour_time() { unsupported(); }
FMT_CONSTEXPR void on_24_hour_time() { unsupported(); }
FMT_CONSTEXPR void on_iso_time() { unsupported(); }
FMT_CONSTEXPR void on_am_pm() { unsupported(); }
FMT_CONSTEXPR void on_duration_value() { unsupported(); }
FMT_CONSTEXPR void on_duration_unit() { unsupported(); }
FMT_CONSTEXPR void on_utc_offset() { unsupported(); }
FMT_CONSTEXPR void on_tz_name() { unsupported(); }
};
struct chrono_format_checker : null_chrono_spec_handler<chrono_format_checker> {
FMT_NORETURN void unsupported() { FMT_THROW(format_error("no date")); }
template <typename Char>
FMT_CONSTEXPR void on_text(const Char*, const Char*) {}
FMT_CONSTEXPR void on_24_hour(numeric_system) {}
FMT_CONSTEXPR void on_12_hour(numeric_system) {}
FMT_CONSTEXPR void on_minute(numeric_system) {}
FMT_CONSTEXPR void on_second(numeric_system) {}
FMT_CONSTEXPR void on_12_hour_time() {}
FMT_CONSTEXPR void on_24_hour_time() {}
FMT_CONSTEXPR void on_iso_time() {}
FMT_CONSTEXPR void on_am_pm() {}
FMT_CONSTEXPR void on_duration_value() {}
FMT_CONSTEXPR void on_duration_unit() {}
};
template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
inline bool isnan(T) {
return false;
}
template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
inline bool isnan(T value) {
return std::isnan(value);
}
template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
inline bool isfinite(T) {
return true;
}
template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
inline bool isfinite(T value) {
return std::isfinite(value);
}
// Converts value to int and checks that it's in the range [0, upper).
template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
inline int to_nonnegative_int(T value, int upper) {
FMT_ASSERT(value >= 0 && to_unsigned(value) <= to_unsigned(upper),
"invalid value");
(void)upper;
return static_cast<int>(value);
}
template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
inline int to_nonnegative_int(T value, int upper) {
FMT_ASSERT(
std::isnan(value) || (value >= 0 && value <= static_cast<T>(upper)),
"invalid value");
(void)upper;
return static_cast<int>(value);
}
template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
inline T mod(T x, int y) {
return x % static_cast<T>(y);
}
template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
inline T mod(T x, int y) {
return std::fmod(x, static_cast<T>(y));
}
// If T is an integral type, maps T to its unsigned counterpart, otherwise
// leaves it unchanged (unlike std::make_unsigned).
template <typename T, bool INTEGRAL = std::is_integral<T>::value>
struct make_unsigned_or_unchanged {
using type = T;
};
template <typename T> struct make_unsigned_or_unchanged<T, true> {
using type = typename std::make_unsigned<T>::type;
};
#if FMT_SAFE_DURATION_CAST
// throwing version of safe_duration_cast
template <typename To, typename FromRep, typename FromPeriod>
To fmt_safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from) {
int ec;
To to = safe_duration_cast::safe_duration_cast<To>(from, ec);
if (ec) FMT_THROW(format_error("cannot format duration"));
return to;
}
#endif
template <typename Rep, typename Period,
FMT_ENABLE_IF(std::is_integral<Rep>::value)>
inline std::chrono::duration<Rep, std::milli> get_milliseconds(
std::chrono::duration<Rep, Period> d) {
// this may overflow and/or the result may not fit in the
// target type.
#if FMT_SAFE_DURATION_CAST
using CommonSecondsType =
typename std::common_type<decltype(d), std::chrono::seconds>::type;
const auto d_as_common = fmt_safe_duration_cast<CommonSecondsType>(d);
const auto d_as_whole_seconds =
fmt_safe_duration_cast<std::chrono::seconds>(d_as_common);
// this conversion should be nonproblematic
const auto diff = d_as_common - d_as_whole_seconds;
const auto ms =
fmt_safe_duration_cast<std::chrono::duration<Rep, std::milli>>(diff);
return ms;
#else
auto s = std::chrono::duration_cast<std::chrono::seconds>(d);
return std::chrono::duration_cast<std::chrono::milliseconds>(d - s);
#endif
}
template <typename Rep, typename Period,
FMT_ENABLE_IF(std::is_floating_point<Rep>::value)>
inline std::chrono::duration<Rep, std::milli> get_milliseconds(
std::chrono::duration<Rep, Period> d) {
using common_type = typename std::common_type<Rep, std::intmax_t>::type;
auto ms = mod(d.count() * static_cast<common_type>(Period::num) /
static_cast<common_type>(Period::den) * 1000,
1000);
return std::chrono::duration<Rep, std::milli>(static_cast<Rep>(ms));
}
template <typename Char, typename Rep, typename OutputIt,
FMT_ENABLE_IF(std::is_integral<Rep>::value)>
OutputIt format_duration_value(OutputIt out, Rep val, int) {
return write<Char>(out, val);
}
template <typename Char, typename Rep, typename OutputIt,
FMT_ENABLE_IF(std::is_floating_point<Rep>::value)>
OutputIt format_duration_value(OutputIt out, Rep val, int precision) {
auto specs = basic_format_specs<Char>();
specs.precision = precision;
specs.type = precision > 0 ? 'f' : 'g';
return write<Char>(out, val, specs);
}
template <typename Char, typename OutputIt>
OutputIt copy_unit(string_view unit, OutputIt out, Char) {
return std::copy(unit.begin(), unit.end(), out);
}
template <typename OutputIt>
OutputIt copy_unit(string_view unit, OutputIt out, wchar_t) {
// This works when wchar_t is UTF-32 because units only contain characters
// that have the same representation in UTF-16 and UTF-32.
utf8_to_utf16 u(unit);
return std::copy(u.c_str(), u.c_str() + u.size(), out);
}
template <typename Char, typename Period, typename OutputIt>
OutputIt format_duration_unit(OutputIt out) {
if (const char* unit = get_units<Period>())
return copy_unit(string_view(unit), out, Char());
*out++ = '[';
out = write<Char>(out, Period::num);
if (const_check(Period::den != 1)) {
*out++ = '/';
out = write<Char>(out, Period::den);
}
*out++ = ']';
*out++ = 's';
return out;
}
template <typename FormatContext, typename OutputIt, typename Rep,
typename Period>
struct chrono_formatter {
FormatContext& context;
OutputIt out;
int precision;
bool localized = false;
// rep is unsigned to avoid overflow.
using rep =
conditional_t<std::is_integral<Rep>::value && sizeof(Rep) < sizeof(int),
unsigned, typename make_unsigned_or_unchanged<Rep>::type>;
rep val;
using seconds = std::chrono::duration<rep>;
seconds s;
using milliseconds = std::chrono::duration<rep, std::milli>;
bool negative;
using char_type = typename FormatContext::char_type;
explicit chrono_formatter(FormatContext& ctx, OutputIt o,
std::chrono::duration<Rep, Period> d)
: context(ctx),
out(o),
val(static_cast<rep>(d.count())),
negative(false) {
if (d.count() < 0) {
val = 0 - val;
negative = true;
}
// this may overflow and/or the result may not fit in the
// target type.
#if FMT_SAFE_DURATION_CAST
// might need checked conversion (rep!=Rep)
auto tmpval = std::chrono::duration<rep, Period>(val);
s = fmt_safe_duration_cast<seconds>(tmpval);
#else
s = std::chrono::duration_cast<seconds>(
std::chrono::duration<rep, Period>(val));
#endif
}
// returns true if nan or inf, writes to out.
bool handle_nan_inf() {
if (isfinite(val)) {
return false;
}
if (isnan(val)) {
write_nan();
return true;
}
// must be +-inf
if (val > 0) {
write_pinf();
} else {
write_ninf();
}
return true;
}
Rep hour() const { return static_cast<Rep>(mod((s.count() / 3600), 24)); }
Rep hour12() const {
Rep hour = static_cast<Rep>(mod((s.count() / 3600), 12));
return hour <= 0 ? 12 : hour;
}
Rep minute() const { return static_cast<Rep>(mod((s.count() / 60), 60)); }
Rep second() const { return static_cast<Rep>(mod(s.count(), 60)); }
std::tm time() const {
auto time = std::tm();
time.tm_hour = to_nonnegative_int(hour(), 24);
time.tm_min = to_nonnegative_int(minute(), 60);
time.tm_sec = to_nonnegative_int(second(), 60);
return time;
}
void write_sign() {
if (negative) {
*out++ = '-';
negative = false;
}
}
void write(Rep value, int width) {
write_sign();
if (isnan(value)) return write_nan();
uint32_or_64_or_128_t<int> n =
to_unsigned(to_nonnegative_int(value, max_value<int>()));
int num_digits = detail::count_digits(n);
if (width > num_digits) out = std::fill_n(out, width - num_digits, '0');
out = format_decimal<char_type>(out, n, num_digits).end;
}
void write_nan() { std::copy_n("nan", 3, out); }
void write_pinf() { std::copy_n("inf", 3, out); }
void write_ninf() { std::copy_n("-inf", 4, out); }
void format_localized(const tm& time, char format, char modifier = 0) {
if (isnan(val)) return write_nan();
auto locale = localized ? context.locale().template get<std::locale>()
: std::locale::classic();
auto& facet = std::use_facet<std::time_put<char_type>>(locale);
std::basic_ostringstream<char_type> os;
os.imbue(locale);
facet.put(os, os, ' ', &time, format, modifier);
auto str = os.str();
std::copy(str.begin(), str.end(), out);
}
void on_text(const char_type* begin, const char_type* end) {
std::copy(begin, end, out);
}
// These are not implemented because durations don't have date information.
void on_abbr_weekday() {}
void on_full_weekday() {}
void on_dec0_weekday(numeric_system) {}
void on_dec1_weekday(numeric_system) {}
void on_abbr_month() {}
void on_full_month() {}
void on_datetime(numeric_system) {}
void on_loc_date(numeric_system) {}
void on_loc_time(numeric_system) {}
void on_us_date() {}
void on_iso_date() {}
void on_utc_offset() {}
void on_tz_name() {}
void on_24_hour(numeric_system ns) {
if (handle_nan_inf()) return;
if (ns == numeric_system::standard) return write(hour(), 2);
auto time = tm();
time.tm_hour = to_nonnegative_int(hour(), 24);
format_localized(time, 'H', 'O');
}
void on_12_hour(numeric_system ns) {
if (handle_nan_inf()) return;
if (ns == numeric_system::standard) return write(hour12(), 2);
auto time = tm();
time.tm_hour = to_nonnegative_int(hour12(), 12);
format_localized(time, 'I', 'O');
}
void on_minute(numeric_system ns) {
if (handle_nan_inf()) return;
if (ns == numeric_system::standard) return write(minute(), 2);
auto time = tm();
time.tm_min = to_nonnegative_int(minute(), 60);
format_localized(time, 'M', 'O');
}
void on_second(numeric_system ns) {
if (handle_nan_inf()) return;
if (ns == numeric_system::standard) {
write(second(), 2);
#if FMT_SAFE_DURATION_CAST
// convert rep->Rep
using duration_rep = std::chrono::duration<rep, Period>;
using duration_Rep = std::chrono::duration<Rep, Period>;
auto tmpval = fmt_safe_duration_cast<duration_Rep>(duration_rep{val});
#else
auto tmpval = std::chrono::duration<Rep, Period>(val);
#endif
auto ms = get_milliseconds(tmpval);
if (ms != std::chrono::milliseconds(0)) {
*out++ = '.';
write(ms.count(), 3);
}
return;
}
auto time = tm();
time.tm_sec = to_nonnegative_int(second(), 60);
format_localized(time, 'S', 'O');
}
void on_12_hour_time() {
if (handle_nan_inf()) return;
format_localized(time(), 'r');
}
void on_24_hour_time() {
if (handle_nan_inf()) {
*out++ = ':';
handle_nan_inf();
return;
}
write(hour(), 2);
*out++ = ':';
write(minute(), 2);
}
void on_iso_time() {
on_24_hour_time();
*out++ = ':';
if (handle_nan_inf()) return;
write(second(), 2);
}
void on_am_pm() {
if (handle_nan_inf()) return;
format_localized(time(), 'p');
}
void on_duration_value() {
if (handle_nan_inf()) return;
write_sign();
out = format_duration_value<char_type>(out, val, precision);
}
void on_duration_unit() {
out = format_duration_unit<char_type, Period>(out);
}
};
FMT_END_DETAIL_NAMESPACE
#if defined(__cpp_lib_chrono) && __cpp_lib_chrono >= 201907
using weekday = std::chrono::weekday;
#else
// A fallback version of weekday.
class weekday {
private:
unsigned char value;
public:
weekday() = default;
explicit constexpr weekday(unsigned wd) noexcept
: value(static_cast<unsigned char>(wd != 7 ? wd : 0)) {}
constexpr unsigned c_encoding() const noexcept { return value; }
};
#endif
// A rudimentary weekday formatter.
template <> struct formatter<weekday> {
private:
bool localized = false;
public:
FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> decltype(ctx.begin()) {
auto begin = ctx.begin(), end = ctx.end();
if (begin != end && *begin == 'L') {
++begin;
localized = true;
}
return begin;
}
auto format(weekday wd, format_context& ctx) -> decltype(ctx.out()) {
auto tm = std::tm();
tm.tm_wday = static_cast<int>(wd.c_encoding());
auto&& os = std::ostringstream();
using iterator = std::ostreambuf_iterator<char>;
auto& loc = localized ? ctx.locale().template get<std::locale>()
: std::locale::classic();
const auto& tp = std::use_facet<std::time_put<char, iterator>>(loc);
auto fmt = string_view("%a");
auto end =
tp.put(iterator(os.rdbuf()), os, ' ', &tm, fmt.begin(), fmt.end());
if (end.failed()) FMT_THROW(format_error("failed to format time"));
auto s = os.str();
if (detail::is_utf8() && localized) {
// char16_t and char32_t codecvts are broken in MSVC (linkage errors).
using code_unit = conditional_t<FMT_MSC_VER, wchar_t, char16_t>;
auto& f =
std::use_facet<std::codecvt<code_unit, char, std::mbstate_t>>(loc);
auto mb = std::mbstate_t();
const char* from_next = nullptr;
code_unit* to_next = nullptr;
constexpr size_t buf_size = 100;
code_unit buf[buf_size] = {};
auto result = f.in(mb, s.data(), s.data() + s.size(), from_next, buf,
buf + buf_size, to_next);
if (result != std::codecvt_base::ok)
FMT_THROW(format_error("failed to format time"));
s.clear();
for (code_unit* p = buf; p != to_next; ++p) {
code_unit c = *p;
if (c < 0x80) {
s.push_back(static_cast<char>(c));
} else if (c < 0x800) {
s.push_back(static_cast<char>(0xc0 | (c >> 6)));
s.push_back(static_cast<char>(0x80 | (c & 0x3f)));
} else {
FMT_THROW(format_error("failed to format time"));
}
}
}
return std::copy(s.begin(), s.end(), ctx.out());
}
};
template <typename Rep, typename Period, typename Char>
struct formatter<std::chrono::duration<Rep, Period>, Char> {
private:
basic_format_specs<Char> specs;
int precision = -1;
using arg_ref_type = detail::arg_ref<Char>;
arg_ref_type width_ref;
arg_ref_type precision_ref;
bool localized = false;
basic_string_view<Char> format_str;
using duration = std::chrono::duration<Rep, Period>;
struct spec_handler {
formatter& f;
basic_format_parse_context<Char>& context;
basic_string_view<Char> format_str;
template <typename Id> FMT_CONSTEXPR arg_ref_type make_arg_ref(Id arg_id) {
context.check_arg_id(arg_id);
return arg_ref_type(arg_id);
}
FMT_CONSTEXPR arg_ref_type make_arg_ref(basic_string_view<Char> arg_id) {
context.check_arg_id(arg_id);
return arg_ref_type(arg_id);
}
FMT_CONSTEXPR arg_ref_type make_arg_ref(detail::auto_id) {
return arg_ref_type(context.next_arg_id());
}
void on_error(const char* msg) { FMT_THROW(format_error(msg)); }
FMT_CONSTEXPR void on_fill(basic_string_view<Char> fill) {
f.specs.fill = fill;
}
FMT_CONSTEXPR void on_align(align_t align) { f.specs.align = align; }
FMT_CONSTEXPR void on_width(int width) { f.specs.width = width; }
FMT_CONSTEXPR void on_precision(int _precision) {
f.precision = _precision;
}
FMT_CONSTEXPR void end_precision() {}
template <typename Id> FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
f.width_ref = make_arg_ref(arg_id);
}
template <typename Id> FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
f.precision_ref = make_arg_ref(arg_id);
}
};
using iterator = typename basic_format_parse_context<Char>::iterator;
struct parse_range {
iterator begin;
iterator end;
};
FMT_CONSTEXPR parse_range do_parse(basic_format_parse_context<Char>& ctx) {
auto begin = ctx.begin(), end = ctx.end();
if (begin == end || *begin == '}') return {begin, begin};
spec_handler handler{*this, ctx, format_str};
begin = detail::parse_align(begin, end, handler);
if (begin == end) return {begin, begin};
begin = detail::parse_width(begin, end, handler);
if (begin == end) return {begin, begin};
if (*begin == '.') {
if (std::is_floating_point<Rep>::value)
begin = detail::parse_precision(begin, end, handler);
else
handler.on_error("precision not allowed for this argument type");
}
if (begin != end && *begin == 'L') {
++begin;
localized = true;
}
end = parse_chrono_format(begin, end, detail::chrono_format_checker());
return {begin, end};
}
public:
FMT_CONSTEXPR auto parse(basic_format_parse_context<Char>& ctx)
-> decltype(ctx.begin()) {
auto range = do_parse(ctx);
format_str = basic_string_view<Char>(
&*range.begin, detail::to_unsigned(range.end - range.begin));
return range.end;
}
template <typename FormatContext>
auto format(const duration& d, FormatContext& ctx) const
-> decltype(ctx.out()) {
auto specs_copy = specs;
auto precision_copy = precision;
auto begin = format_str.begin(), end = format_str.end();
// As a possible future optimization, we could avoid extra copying if width
// is not specified.
basic_memory_buffer<Char> buf;
auto out = std::back_inserter(buf);
detail::handle_dynamic_spec<detail::width_checker>(specs_copy.width,
width_ref, ctx);
detail::handle_dynamic_spec<detail::precision_checker>(precision_copy,
precision_ref, ctx);
if (begin == end || *begin == '}') {
out = detail::format_duration_value<Char>(out, d.count(), precision_copy);
detail::format_duration_unit<Char, Period>(out);
} else {
detail::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
ctx, out, d);
f.precision = precision_copy;
f.localized = localized;
parse_chrono_format(begin, end, f);
}
return detail::write(
ctx.out(), basic_string_view<Char>(buf.data(), buf.size()), specs_copy);
}
};
FMT_MODULE_EXPORT_END
FMT_END_NAMESPACE
#endif // FMT_CHRONO_H_