fmtlegacy/include/fmt/format-inl.h
2018-11-14 12:07:39 -08:00

972 lines
32 KiB
C++

// Formatting library for C++
//
// Copyright (c) 2012 - 2016, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
#ifndef FMT_FORMAT_INL_H_
#define FMT_FORMAT_INL_H_
#include "format.h"
#include <string.h>
#include <cctype>
#include <cerrno>
#include <climits>
#include <cmath>
#include <cstdarg>
#include <cstddef> // for std::ptrdiff_t
#include <cstring> // for std::memmove
#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
# include <locale>
#endif
#if FMT_USE_WINDOWS_H
# if !defined(FMT_HEADER_ONLY) && !defined(WIN32_LEAN_AND_MEAN)
# define WIN32_LEAN_AND_MEAN
# endif
# if defined(NOMINMAX) || defined(FMT_WIN_MINMAX)
# include <windows.h>
# else
# define NOMINMAX
# include <windows.h>
# undef NOMINMAX
# endif
#endif
#if FMT_EXCEPTIONS
# define FMT_TRY try
# define FMT_CATCH(x) catch (x)
#else
# define FMT_TRY if (true)
# define FMT_CATCH(x) if (false)
#endif
#ifdef _MSC_VER
# pragma warning(push)
# pragma warning(disable: 4127) // conditional expression is constant
# pragma warning(disable: 4702) // unreachable code
// Disable deprecation warning for strerror. The latter is not called but
// MSVC fails to detect it.
# pragma warning(disable: 4996)
#endif
// Dummy implementations of strerror_r and strerror_s called if corresponding
// system functions are not available.
inline fmt::internal::null<> strerror_r(int, char *, ...) {
return fmt::internal::null<>();
}
inline fmt::internal::null<> strerror_s(char *, std::size_t, ...) {
return fmt::internal::null<>();
}
FMT_BEGIN_NAMESPACE
namespace {
#ifndef _MSC_VER
# define FMT_SNPRINTF snprintf
#else // _MSC_VER
inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
va_list args;
va_start(args, format);
int result = vsnprintf_s(buffer, size, _TRUNCATE, format, args);
va_end(args);
return result;
}
# define FMT_SNPRINTF fmt_snprintf
#endif // _MSC_VER
#if defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
# define FMT_SWPRINTF snwprintf
#else
# define FMT_SWPRINTF swprintf
#endif // defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
typedef void (*FormatFunc)(internal::buffer &, int, string_view);
// Portable thread-safe version of strerror.
// Sets buffer to point to a string describing the error code.
// This can be either a pointer to a string stored in buffer,
// or a pointer to some static immutable string.
// Returns one of the following values:
// 0 - success
// ERANGE - buffer is not large enough to store the error message
// other - failure
// Buffer should be at least of size 1.
int safe_strerror(
int error_code, char *&buffer, std::size_t buffer_size) FMT_NOEXCEPT {
FMT_ASSERT(buffer != FMT_NULL && buffer_size != 0, "invalid buffer");
class dispatcher {
private:
int error_code_;
char *&buffer_;
std::size_t buffer_size_;
// A noop assignment operator to avoid bogus warnings.
void operator=(const dispatcher &) {}
// Handle the result of XSI-compliant version of strerror_r.
int handle(int result) {
// glibc versions before 2.13 return result in errno.
return result == -1 ? errno : result;
}
// Handle the result of GNU-specific version of strerror_r.
int handle(char *message) {
// If the buffer is full then the message is probably truncated.
if (message == buffer_ && strlen(buffer_) == buffer_size_ - 1)
return ERANGE;
buffer_ = message;
return 0;
}
// Handle the case when strerror_r is not available.
int handle(internal::null<>) {
return fallback(strerror_s(buffer_, buffer_size_, error_code_));
}
// Fallback to strerror_s when strerror_r is not available.
int fallback(int result) {
// If the buffer is full then the message is probably truncated.
return result == 0 && strlen(buffer_) == buffer_size_ - 1 ?
ERANGE : result;
}
// Fallback to strerror if strerror_r and strerror_s are not available.
int fallback(internal::null<>) {
errno = 0;
buffer_ = strerror(error_code_);
return errno;
}
public:
dispatcher(int err_code, char *&buf, std::size_t buf_size)
: error_code_(err_code), buffer_(buf), buffer_size_(buf_size) {}
int run() {
return handle(strerror_r(error_code_, buffer_, buffer_size_));
}
};
return dispatcher(error_code, buffer, buffer_size).run();
}
void format_error_code(internal::buffer &out, int error_code,
string_view message) FMT_NOEXCEPT {
// Report error code making sure that the output fits into
// inline_buffer_size to avoid dynamic memory allocation and potential
// bad_alloc.
out.resize(0);
static const char SEP[] = ": ";
static const char ERROR_STR[] = "error ";
// Subtract 2 to account for terminating null characters in SEP and ERROR_STR.
std::size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
typedef internal::int_traits<int>::main_type main_type;
main_type abs_value = static_cast<main_type>(error_code);
if (internal::is_negative(error_code)) {
abs_value = 0 - abs_value;
++error_code_size;
}
error_code_size += internal::count_digits(abs_value);
writer w(out);
if (message.size() <= inline_buffer_size - error_code_size) {
w.write(message);
w.write(SEP);
}
w.write(ERROR_STR);
w.write(error_code);
assert(out.size() <= inline_buffer_size);
}
void report_error(FormatFunc func, int error_code,
string_view message) FMT_NOEXCEPT {
memory_buffer full_message;
func(full_message, error_code, message);
// Use Writer::data instead of Writer::c_str to avoid potential memory
// allocation.
std::fwrite(full_message.data(), full_message.size(), 1, stderr);
std::fputc('\n', stderr);
}
} // namespace
FMT_FUNC size_t internal::count_code_points(basic_string_view<char8_t> s) {
const char8_t *data = s.data();
size_t num_code_points = 0;
for (size_t i = 0, size = s.size(); i != size; ++i) {
if ((data[i] & 0xc0) != 0x80)
++num_code_points;
}
return num_code_points;
}
#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
namespace internal {
template <typename Locale>
locale_ref::locale_ref(const Locale &loc) : locale_(&loc) {
static_assert(std::is_same<Locale, std::locale>::value, "");
}
template <typename Locale>
Locale locale_ref::get() const {
static_assert(std::is_same<Locale, std::locale>::value, "");
return locale_ ? *static_cast<const std::locale*>(locale_) : std::locale();
}
template <typename Char>
FMT_FUNC Char thousands_sep_impl(locale_ref loc) {
return std::use_facet<std::numpunct<Char> >(
loc.get<std::locale>()).thousands_sep();
}
}
#else
template <typename Char>
FMT_FUNC Char internal::thousands_sep(locale_ref) {
return FMT_STATIC_THOUSANDS_SEPARATOR;
}
#endif
FMT_FUNC void system_error::init(
int err_code, string_view format_str, format_args args) {
error_code_ = err_code;
memory_buffer buffer;
format_system_error(buffer, err_code, vformat(format_str, args));
std::runtime_error &base = *this;
base = std::runtime_error(to_string(buffer));
}
namespace internal {
template <typename T>
int char_traits<char>::format_float(
char *buffer, std::size_t size, const char *format, int precision, T value) {
return precision < 0 ?
FMT_SNPRINTF(buffer, size, format, value) :
FMT_SNPRINTF(buffer, size, format, precision, value);
}
template <typename T>
int char_traits<wchar_t>::format_float(
wchar_t *buffer, std::size_t size, const wchar_t *format, int precision,
T value) {
return precision < 0 ?
FMT_SWPRINTF(buffer, size, format, value) :
FMT_SWPRINTF(buffer, size, format, precision, value);
}
template <typename T>
const char basic_data<T>::DIGITS[] =
"0001020304050607080910111213141516171819"
"2021222324252627282930313233343536373839"
"4041424344454647484950515253545556575859"
"6061626364656667686970717273747576777879"
"8081828384858687888990919293949596979899";
#define FMT_POWERS_OF_10(factor) \
factor * 10, \
factor * 100, \
factor * 1000, \
factor * 10000, \
factor * 100000, \
factor * 1000000, \
factor * 10000000, \
factor * 100000000, \
factor * 1000000000
template <typename T>
const uint32_t basic_data<T>::POWERS_OF_10_32[] = {
1, FMT_POWERS_OF_10(1)
};
template <typename T>
const uint32_t basic_data<T>::ZERO_OR_POWERS_OF_10_32[] = {
0, FMT_POWERS_OF_10(1)
};
template <typename T>
const uint64_t basic_data<T>::ZERO_OR_POWERS_OF_10_64[] = {
0,
FMT_POWERS_OF_10(1),
FMT_POWERS_OF_10(1000000000ull),
10000000000000000000ull
};
// Normalized 64-bit significands of pow(10, k), for k = -348, -340, ..., 340.
// These are generated by support/compute-powers.py.
template <typename T>
const uint64_t basic_data<T>::POW10_SIGNIFICANDS[] = {
0xfa8fd5a0081c0288, 0xbaaee17fa23ebf76, 0x8b16fb203055ac76,
0xcf42894a5dce35ea, 0x9a6bb0aa55653b2d, 0xe61acf033d1a45df,
0xab70fe17c79ac6ca, 0xff77b1fcbebcdc4f, 0xbe5691ef416bd60c,
0x8dd01fad907ffc3c, 0xd3515c2831559a83, 0x9d71ac8fada6c9b5,
0xea9c227723ee8bcb, 0xaecc49914078536d, 0x823c12795db6ce57,
0xc21094364dfb5637, 0x9096ea6f3848984f, 0xd77485cb25823ac7,
0xa086cfcd97bf97f4, 0xef340a98172aace5, 0xb23867fb2a35b28e,
0x84c8d4dfd2c63f3b, 0xc5dd44271ad3cdba, 0x936b9fcebb25c996,
0xdbac6c247d62a584, 0xa3ab66580d5fdaf6, 0xf3e2f893dec3f126,
0xb5b5ada8aaff80b8, 0x87625f056c7c4a8b, 0xc9bcff6034c13053,
0x964e858c91ba2655, 0xdff9772470297ebd, 0xa6dfbd9fb8e5b88f,
0xf8a95fcf88747d94, 0xb94470938fa89bcf, 0x8a08f0f8bf0f156b,
0xcdb02555653131b6, 0x993fe2c6d07b7fac, 0xe45c10c42a2b3b06,
0xaa242499697392d3, 0xfd87b5f28300ca0e, 0xbce5086492111aeb,
0x8cbccc096f5088cc, 0xd1b71758e219652c, 0x9c40000000000000,
0xe8d4a51000000000, 0xad78ebc5ac620000, 0x813f3978f8940984,
0xc097ce7bc90715b3, 0x8f7e32ce7bea5c70, 0xd5d238a4abe98068,
0x9f4f2726179a2245, 0xed63a231d4c4fb27, 0xb0de65388cc8ada8,
0x83c7088e1aab65db, 0xc45d1df942711d9a, 0x924d692ca61be758,
0xda01ee641a708dea, 0xa26da3999aef774a, 0xf209787bb47d6b85,
0xb454e4a179dd1877, 0x865b86925b9bc5c2, 0xc83553c5c8965d3d,
0x952ab45cfa97a0b3, 0xde469fbd99a05fe3, 0xa59bc234db398c25,
0xf6c69a72a3989f5c, 0xb7dcbf5354e9bece, 0x88fcf317f22241e2,
0xcc20ce9bd35c78a5, 0x98165af37b2153df, 0xe2a0b5dc971f303a,
0xa8d9d1535ce3b396, 0xfb9b7cd9a4a7443c, 0xbb764c4ca7a44410,
0x8bab8eefb6409c1a, 0xd01fef10a657842c, 0x9b10a4e5e9913129,
0xe7109bfba19c0c9d, 0xac2820d9623bf429, 0x80444b5e7aa7cf85,
0xbf21e44003acdd2d, 0x8e679c2f5e44ff8f, 0xd433179d9c8cb841,
0x9e19db92b4e31ba9, 0xeb96bf6ebadf77d9, 0xaf87023b9bf0ee6b,
};
// Binary exponents of pow(10, k), for k = -348, -340, ..., 340, corresponding
// to significands above.
template <typename T>
const int16_t basic_data<T>::POW10_EXPONENTS[] = {
-1220, -1193, -1166, -1140, -1113, -1087, -1060, -1034, -1007, -980, -954,
-927, -901, -874, -847, -821, -794, -768, -741, -715, -688, -661,
-635, -608, -582, -555, -529, -502, -475, -449, -422, -396, -369,
-343, -316, -289, -263, -236, -210, -183, -157, -130, -103, -77,
-50, -24, 3, 30, 56, 83, 109, 136, 162, 189, 216,
242, 269, 295, 322, 348, 375, 402, 428, 455, 481, 508,
534, 561, 588, 614, 641, 667, 694, 720, 747, 774, 800,
827, 853, 880, 907, 933, 960, 986, 1013, 1039, 1066
};
template <typename T> const char basic_data<T>::FOREGROUND_COLOR[] = "\x1b[38;2;";
template <typename T> const char basic_data<T>::BACKGROUND_COLOR[] = "\x1b[48;2;";
template <typename T> const char basic_data<T>::RESET_COLOR[] = "\x1b[0m";
template <typename T> const wchar_t basic_data<T>::WRESET_COLOR[] = L"\x1b[0m";
// A handmade floating-point number f * pow(2, e).
class fp {
private:
typedef uint64_t significand_type;
// All sizes are in bits.
static FMT_CONSTEXPR_DECL const int char_size =
std::numeric_limits<unsigned char>::digits;
// Subtract 1 to account for an implicit most significant bit in the
// normalized form.
static FMT_CONSTEXPR_DECL const int double_significand_size =
std::numeric_limits<double>::digits - 1;
static FMT_CONSTEXPR_DECL const uint64_t implicit_bit =
1ull << double_significand_size;
public:
significand_type f;
int e;
static FMT_CONSTEXPR_DECL const int significand_size =
sizeof(significand_type) * char_size;
fp(): f(0), e(0) {}
fp(uint64_t f, int e): f(f), e(e) {}
// Constructs fp from an IEEE754 double. It is a template to prevent compile
// errors on platforms where double is not IEEE754.
template <typename Double>
explicit fp(Double d) {
// Assume double is in the format [sign][exponent][significand].
typedef std::numeric_limits<Double> limits;
const int double_size = static_cast<int>(sizeof(Double) * char_size);
const int exponent_size =
double_size - double_significand_size - 1; // -1 for sign
const uint64_t significand_mask = implicit_bit - 1;
const uint64_t exponent_mask = (~0ull >> 1) & ~significand_mask;
const int exponent_bias = (1 << exponent_size) - limits::max_exponent - 1;
auto u = bit_cast<uint64_t>(d);
auto biased_e = (u & exponent_mask) >> double_significand_size;
f = u & significand_mask;
if (biased_e != 0)
f += implicit_bit;
else
biased_e = 1; // Subnormals use biased exponent 1 (min exponent).
e = static_cast<int>(biased_e - exponent_bias - double_significand_size);
}
// Normalizes the value converted from double and multiplied by (1 << SHIFT).
template <int SHIFT = 0>
void normalize() {
// Handle subnormals.
auto shifted_implicit_bit = implicit_bit << SHIFT;
while ((f & shifted_implicit_bit) == 0) {
f <<= 1;
--e;
}
// Subtract 1 to account for hidden bit.
auto offset = significand_size - double_significand_size - SHIFT - 1;
f <<= offset;
e -= offset;
}
// Compute lower and upper boundaries (m^- and m^+ in the Grisu paper), where
// a boundary is a value half way between the number and its predecessor
// (lower) or successor (upper). The upper boundary is normalized and lower
// has the same exponent but may be not normalized.
void compute_boundaries(fp &lower, fp &upper) const {
lower = f == implicit_bit ?
fp((f << 2) - 1, e - 2) : fp((f << 1) - 1, e - 1);
upper = fp((f << 1) + 1, e - 1);
upper.normalize<1>(); // 1 is to account for the exponent shift above.
lower.f <<= lower.e - upper.e;
lower.e = upper.e;
}
};
// Returns an fp number representing x - y. Result may not be normalized.
inline fp operator-(fp x, fp y) {
FMT_ASSERT(x.f >= y.f && x.e == y.e, "invalid operands");
return fp(x.f - y.f, x.e);
}
// Computes an fp number r with r.f = x.f * y.f / pow(2, 64) rounded to nearest
// with half-up tie breaking, r.e = x.e + y.e + 64. Result may not be normalized.
FMT_API fp operator*(fp x, fp y);
// Returns cached power (of 10) c_k = c_k.f * pow(2, c_k.e) such that its
// (binary) exponent satisfies min_exponent <= c_k.e <= min_exponent + 3.
FMT_API fp get_cached_power(int min_exponent, int &pow10_exponent);
FMT_FUNC fp operator*(fp x, fp y) {
// Multiply 32-bit parts of significands.
uint64_t mask = (1ULL << 32) - 1;
uint64_t a = x.f >> 32, b = x.f & mask;
uint64_t c = y.f >> 32, d = y.f & mask;
uint64_t ac = a * c, bc = b * c, ad = a * d, bd = b * d;
// Compute mid 64-bit of result and round.
uint64_t mid = (bd >> 32) + (ad & mask) + (bc & mask) + (1U << 31);
return fp(ac + (ad >> 32) + (bc >> 32) + (mid >> 32), x.e + y.e + 64);
}
FMT_FUNC fp get_cached_power(int min_exponent, int &pow10_exponent) {
const double one_over_log2_10 = 0.30102999566398114; // 1 / log2(10)
int index = static_cast<int>(std::ceil(
(min_exponent + fp::significand_size - 1) * one_over_log2_10));
// Decimal exponent of the first (smallest) cached power of 10.
const int first_dec_exp = -348;
// Difference between 2 consecutive decimal exponents in cached powers of 10.
const int dec_exp_step = 8;
index = (index - first_dec_exp - 1) / dec_exp_step + 1;
pow10_exponent = first_dec_exp + index * dec_exp_step;
return fp(data::POW10_SIGNIFICANDS[index], data::POW10_EXPONENTS[index]);
}
FMT_FUNC bool grisu2_round(
char *buffer, size_t &size, size_t max_digits, uint64_t delta,
uint64_t remainder, uint64_t exp, uint64_t diff, int &exp10) {
while (remainder < diff && delta - remainder >= exp &&
(remainder + exp < diff || diff - remainder > remainder + exp - diff)) {
--buffer[size - 1];
remainder += exp;
}
if (size > max_digits) {
--size;
++exp10;
if (buffer[size] >= '5')
return false;
}
return true;
}
// Generates output using Grisu2 digit-gen algorithm.
FMT_FUNC bool grisu2_gen_digits(
char *buffer, size_t &size, uint32_t hi, uint64_t lo, int &exp,
uint64_t delta, const fp &one, const fp &diff, size_t max_digits) {
// Generate digits for the most significant part (hi).
while (exp > 0) {
uint32_t digit = 0;
// This optimization by miloyip reduces the number of integer divisions by
// one per iteration.
switch (exp) {
case 10: digit = hi / 1000000000; hi %= 1000000000; break;
case 9: digit = hi / 100000000; hi %= 100000000; break;
case 8: digit = hi / 10000000; hi %= 10000000; break;
case 7: digit = hi / 1000000; hi %= 1000000; break;
case 6: digit = hi / 100000; hi %= 100000; break;
case 5: digit = hi / 10000; hi %= 10000; break;
case 4: digit = hi / 1000; hi %= 1000; break;
case 3: digit = hi / 100; hi %= 100; break;
case 2: digit = hi / 10; hi %= 10; break;
case 1: digit = hi; hi = 0; break;
default:
FMT_ASSERT(false, "invalid number of digits");
}
if (digit != 0 || size != 0)
buffer[size++] = static_cast<char>('0' + digit);
--exp;
uint64_t remainder = (static_cast<uint64_t>(hi) << -one.e) + lo;
if (remainder <= delta || size > max_digits) {
return grisu2_round(
buffer, size, max_digits, delta, remainder,
static_cast<uint64_t>(data::POWERS_OF_10_32[exp]) << -one.e,
diff.f, exp);
}
}
// Generate digits for the least significant part (lo).
for (;;) {
lo *= 10;
delta *= 10;
char digit = static_cast<char>(lo >> -one.e);
if (digit != 0 || size != 0)
buffer[size++] = static_cast<char>('0' + digit);
lo &= one.f - 1;
--exp;
if (lo < delta || size > max_digits) {
return grisu2_round(buffer, size, max_digits, delta, lo, one.f,
diff.f * data::POWERS_OF_10_32[-exp], exp);
}
}
}
#if FMT_CLANG_VERSION
# define FMT_FALLTHROUGH [[clang::fallthrough]];
#elif FMT_GCC_VERSION >= 700
# define FMT_FALLTHROUGH [[gnu::fallthrough]];
#else
# define FMT_FALLTHROUGH
#endif
struct gen_digits_params {
unsigned num_digits;
bool fixed;
bool upper;
bool trailing_zeros;
};
struct prettify_handler {
char *data;
size_t size;
buffer &buf;
explicit prettify_handler(buffer &b, size_t n)
: data(b.data()), size(n), buf(b) {}
~prettify_handler() {
assert(buf.size() >= size);
buf.resize(size);
}
template <typename F>
void insert(size_t pos, size_t n, F f) {
std::memmove(data + pos + n, data + pos, size - pos);
f(data + pos);
size += n;
}
void insert(size_t pos, char c) {
std::memmove(data + pos + 1, data + pos, size - pos);
data[pos] = c;
++size;
}
void append(size_t n, char c) {
std::uninitialized_fill_n(data + size, n, c);
size += n;
}
void append(char c) { data[size++] = c; }
void remove_trailing(char c) {
while (data[size - 1] == c) --size;
}
};
// Writes the exponent exp in the form "[+-]d{2,3}" to buffer.
template <typename Handler>
FMT_FUNC void write_exponent(int exp, Handler &&h) {
FMT_ASSERT(-1000 < exp && exp < 1000, "exponent out of range");
if (exp < 0) {
h.append('-');
exp = -exp;
} else {
h.append('+');
}
if (exp >= 100) {
h.append(static_cast<char>('0' + exp / 100));
exp %= 100;
const char *d = data::DIGITS + exp * 2;
h.append(d[0]);
h.append(d[1]);
} else {
const char *d = data::DIGITS + exp * 2;
h.append(d[0]);
h.append(d[1]);
}
}
struct fill {
size_t n;
void operator()(char *buffer) const {
buffer[0] = '0';
buffer[1] = '.';
std::uninitialized_fill_n(buffer + 2, n, '0');
}
};
// The number is given as v = f * pow(10, exp), where f has size digits.
template <typename Handler>
FMT_FUNC void grisu2_prettify(const gen_digits_params &params,
size_t size, int exp, Handler &&handler) {
if (!params.fixed) {
// Insert a decimal point after the first digit and add an exponent.
handler.insert(1, '.');
exp += static_cast<int>(size) - 1;
if (size < params.num_digits)
handler.append(params.num_digits - size, '0');
handler.append(params.upper ? 'E' : 'e');
write_exponent(exp, handler);
return;
}
// pow(10, full_exp - 1) <= v <= pow(10, full_exp).
int int_size = static_cast<int>(size);
int full_exp = int_size + exp;
const int exp_threshold = 21;
if (int_size <= full_exp && full_exp <= exp_threshold) {
// 1234e7 -> 12340000000[.0+]
handler.append(full_exp - int_size, '0');
int num_zeros = static_cast<int>(params.num_digits) - full_exp;
if (num_zeros > 0 && params.trailing_zeros) {
handler.append('.');
handler.append(num_zeros, '0');
}
} else if (full_exp > 0) {
// 1234e-2 -> 12.34[0+]
handler.insert(full_exp, '.');
if (!params.trailing_zeros) {
// Remove trailing zeros.
handler.remove_trailing('0');
} else if (params.num_digits > size) {
// Add trailing zeros.
size_t num_zeros = params.num_digits - size;
handler.append(num_zeros, '0');
}
} else {
// 1234e-6 -> 0.001234
handler.insert(0, 2 - full_exp, fill{to_unsigned(-full_exp)});
}
}
struct char_counter {
size_t size;
template <typename F>
void insert(size_t, size_t n, F) { size += n; }
void insert(size_t, char) { ++size; }
void append(size_t n, char) { size += n; }
void append(char) { ++size; }
void remove_trailing(char) {}
};
// Converts format specifiers into parameters for digit generation and computes
// output buffer size for a number in the range [pow(10, exp - 1), pow(10, exp)
// or 0 if exp == 1.
FMT_FUNC gen_digits_params process_specs(const core_format_specs &specs,
int exp, buffer &buf) {
auto params = gen_digits_params();
int num_digits = specs.precision >= 0 ? specs.precision : 6;
switch (specs.type) {
case 'G':
params.upper = true;
FMT_FALLTHROUGH
case '\0': case 'g':
params.trailing_zeros = (specs.flags & HASH_FLAG) != 0;
if (-4 <= exp && exp < num_digits + 1) {
params.fixed = true;
if (!specs.type && params.trailing_zeros && exp >= 0)
num_digits = exp + 1;
}
break;
case 'F':
params.upper = true;
FMT_FALLTHROUGH
case 'f': {
params.fixed = true;
params.trailing_zeros = true;
int adjusted_min_digits = num_digits + exp;
if (adjusted_min_digits > 0)
num_digits = adjusted_min_digits;
break;
}
case 'E':
params.upper = true;
FMT_FALLTHROUGH
case 'e':
++num_digits;
break;
}
params.num_digits = to_unsigned(num_digits);
char_counter counter{params.num_digits};
grisu2_prettify(params, params.num_digits, exp - num_digits, counter);
buf.resize(counter.size);
return params;
}
template <typename Double>
FMT_FUNC typename std::enable_if<sizeof(Double) == sizeof(uint64_t), bool>::type
grisu2_format(Double value, buffer &buf, core_format_specs specs) {
FMT_ASSERT(value >= 0, "value is negative");
if (value == 0) {
gen_digits_params params = process_specs(specs, 1, buf);
const size_t size = 1;
buf[0] = '0';
grisu2_prettify(params, size, 0, prettify_handler(buf, size));
return true;
}
fp fp_value(value);
fp lower, upper; // w^- and w^+ in the Grisu paper.
fp_value.compute_boundaries(lower, upper);
// Find a cached power of 10 close to 1 / upper and use it to scale upper.
const int min_exp = -60; // alpha in Grisu.
int cached_exp = 0; // K in Grisu.
auto cached_pow = get_cached_power( // \tilde{c}_{-k} in Grisu.
min_exp - (upper.e + fp::significand_size), cached_exp);
cached_exp = -cached_exp;
upper = upper * cached_pow; // \tilde{M}^+ in Grisu.
--upper.f; // \tilde{M}^+ - 1 ulp -> M^+_{\downarrow}.
fp one(1ull << -upper.e, upper.e);
// hi (p1 in Grisu) contains the most significant digits of scaled_upper.
// hi = floor(upper / one).
uint32_t hi = static_cast<uint32_t>(upper.f >> -one.e);
int exp = static_cast<int>(count_digits(hi)); // kappa in Grisu.
gen_digits_params params = process_specs(specs, cached_exp + exp, buf);
fp_value.normalize();
fp scaled_value = fp_value * cached_pow;
lower = lower * cached_pow; // \tilde{M}^- in Grisu.
++lower.f; // \tilde{M}^- + 1 ulp -> M^-_{\uparrow}.
uint64_t delta = upper.f - lower.f;
fp diff = upper - scaled_value; // wp_w in Grisu.
// lo (p2 in Grisu) contains the least significants digits of scaled_upper.
// lo = supper % one.
uint64_t lo = upper.f & (one.f - 1);
size_t size = 0;
if (!grisu2_gen_digits(buf.data(), size, hi, lo, exp, delta, one, diff,
params.num_digits)) {
buf.clear();
return false;
}
grisu2_prettify(params, size, cached_exp + exp, prettify_handler(buf, size));
return true;
}
template <typename Double>
void sprintf_format(Double value, internal::buffer &buffer,
core_format_specs spec) {
// Buffer capacity must be non-zero, otherwise MSVC's vsnprintf_s will fail.
FMT_ASSERT(buffer.capacity() != 0, "empty buffer");
// Build format string.
enum { MAX_FORMAT_SIZE = 10}; // longest format: %#-*.*Lg
char format[MAX_FORMAT_SIZE];
char *format_ptr = format;
*format_ptr++ = '%';
if (spec.has(HASH_FLAG))
*format_ptr++ = '#';
if (spec.precision >= 0) {
*format_ptr++ = '.';
*format_ptr++ = '*';
}
if (std::is_same<Double, long double>::value)
*format_ptr++ = 'L';
*format_ptr++ = spec.type;
*format_ptr = '\0';
// Format using snprintf.
char *start = FMT_NULL;
for (;;) {
std::size_t buffer_size = buffer.capacity();
start = &buffer[0];
int result = internal::char_traits<char>::format_float(
start, buffer_size, format, spec.precision, value);
if (result >= 0) {
unsigned n = internal::to_unsigned(result);
if (n < buffer.capacity()) {
buffer.resize(n);
break; // The buffer is large enough - continue with formatting.
}
buffer.reserve(n + 1);
} else {
// If result is negative we ask to increase the capacity by at least 1,
// but as std::vector, the buffer grows exponentially.
buffer.reserve(buffer.capacity() + 1);
}
}
}
} // namespace internal
#if FMT_USE_WINDOWS_H
FMT_FUNC internal::utf8_to_utf16::utf8_to_utf16(string_view s) {
static const char ERROR_MSG[] = "cannot convert string from UTF-8 to UTF-16";
if (s.size() > INT_MAX)
FMT_THROW(windows_error(ERROR_INVALID_PARAMETER, ERROR_MSG));
int s_size = static_cast<int>(s.size());
if (s_size == 0) {
// MultiByteToWideChar does not support zero length, handle separately.
buffer_.resize(1);
buffer_[0] = 0;
return;
}
int length = MultiByteToWideChar(
CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, FMT_NULL, 0);
if (length == 0)
FMT_THROW(windows_error(GetLastError(), ERROR_MSG));
buffer_.resize(length + 1);
length = MultiByteToWideChar(
CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, &buffer_[0], length);
if (length == 0)
FMT_THROW(windows_error(GetLastError(), ERROR_MSG));
buffer_[length] = 0;
}
FMT_FUNC internal::utf16_to_utf8::utf16_to_utf8(wstring_view s) {
if (int error_code = convert(s)) {
FMT_THROW(windows_error(error_code,
"cannot convert string from UTF-16 to UTF-8"));
}
}
FMT_FUNC int internal::utf16_to_utf8::convert(wstring_view s) {
if (s.size() > INT_MAX)
return ERROR_INVALID_PARAMETER;
int s_size = static_cast<int>(s.size());
if (s_size == 0) {
// WideCharToMultiByte does not support zero length, handle separately.
buffer_.resize(1);
buffer_[0] = 0;
return 0;
}
int length = WideCharToMultiByte(
CP_UTF8, 0, s.data(), s_size, FMT_NULL, 0, FMT_NULL, FMT_NULL);
if (length == 0)
return GetLastError();
buffer_.resize(length + 1);
length = WideCharToMultiByte(
CP_UTF8, 0, s.data(), s_size, &buffer_[0], length, FMT_NULL, FMT_NULL);
if (length == 0)
return GetLastError();
buffer_[length] = 0;
return 0;
}
FMT_FUNC void windows_error::init(
int err_code, string_view format_str, format_args args) {
error_code_ = err_code;
memory_buffer buffer;
internal::format_windows_error(buffer, err_code, vformat(format_str, args));
std::runtime_error &base = *this;
base = std::runtime_error(to_string(buffer));
}
FMT_FUNC void internal::format_windows_error(
internal::buffer &out, int error_code, string_view message) FMT_NOEXCEPT {
FMT_TRY {
wmemory_buffer buf;
buf.resize(inline_buffer_size);
for (;;) {
wchar_t *system_message = &buf[0];
int result = FormatMessageW(
FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
FMT_NULL, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
system_message, static_cast<uint32_t>(buf.size()), FMT_NULL);
if (result != 0) {
utf16_to_utf8 utf8_message;
if (utf8_message.convert(system_message) == ERROR_SUCCESS) {
writer w(out);
w.write(message);
w.write(": ");
w.write(utf8_message);
return;
}
break;
}
if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
break; // Can't get error message, report error code instead.
buf.resize(buf.size() * 2);
}
} FMT_CATCH(...) {}
format_error_code(out, error_code, message);
}
#endif // FMT_USE_WINDOWS_H
FMT_FUNC void format_system_error(
internal::buffer &out, int error_code, string_view message) FMT_NOEXCEPT {
FMT_TRY {
memory_buffer buf;
buf.resize(inline_buffer_size);
for (;;) {
char *system_message = &buf[0];
int result = safe_strerror(error_code, system_message, buf.size());
if (result == 0) {
writer w(out);
w.write(message);
w.write(": ");
w.write(system_message);
return;
}
if (result != ERANGE)
break; // Can't get error message, report error code instead.
buf.resize(buf.size() * 2);
}
} FMT_CATCH(...) {}
format_error_code(out, error_code, message);
}
FMT_FUNC void internal::error_handler::on_error(const char *message) {
FMT_THROW(format_error(message));
}
FMT_FUNC void report_system_error(
int error_code, fmt::string_view message) FMT_NOEXCEPT {
report_error(format_system_error, error_code, message);
}
#if FMT_USE_WINDOWS_H
FMT_FUNC void report_windows_error(
int error_code, fmt::string_view message) FMT_NOEXCEPT {
report_error(internal::format_windows_error, error_code, message);
}
#endif
FMT_FUNC void vprint(std::FILE *f, string_view format_str, format_args args) {
memory_buffer buffer;
internal::vformat_to(buffer, format_str,
basic_format_args<buffer_context<char>::type>(args));
std::fwrite(buffer.data(), 1, buffer.size(), f);
}
FMT_FUNC void vprint(std::FILE *f, wstring_view format_str, wformat_args args) {
wmemory_buffer buffer;
internal::vformat_to(buffer, format_str, args);
std::fwrite(buffer.data(), sizeof(wchar_t), buffer.size(), f);
}
FMT_FUNC void vprint(string_view format_str, format_args args) {
vprint(stdout, format_str, args);
}
FMT_FUNC void vprint(wstring_view format_str, wformat_args args) {
vprint(stdout, format_str, args);
}
FMT_END_NAMESPACE
#ifdef _MSC_VER
# pragma warning(pop)
#endif
#endif // FMT_FORMAT_INL_H_