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Diffstat (limited to 'stdio-common/printf_fphex.c')
| -rw-r--r-- | stdio-common/printf_fphex.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/stdio-common/printf_fphex.c b/stdio-common/printf_fphex.c new file mode 100644 index 0000000000..d442b56099 --- /dev/null +++ b/stdio-common/printf_fphex.c @@ -0,0 +1,440 @@ +/* Print floating point number in hexadecimal notation according to + ISO C 9X. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <ctype.h> +#include <ieee754.h> +#include <math.h> +#include <printf.h> +#include <stdlib.h> +#include <stdio.h> +#include "_itoa.h" +#include "../locale/localeinfo.h" + +/* #define NDEBUG 1*/ /* Undefine this for debugging assertions. */ +#include <assert.h> + +/* This defines make it possible to use the same code for GNU C library and + the GNU I/O library. */ +#ifdef USE_IN_LIBIO +# include <libioP.h> +# define PUT(f, s, n) _IO_sputn (f, s, n) +# define PAD(f, c, n) _IO_padn (f, c, n) +/* We use this file GNU C library and GNU I/O library. So make + names equal. */ +# undef putc +# define putc(c, f) _IO_putc_unlocked (c, f) +# define size_t _IO_size_t +# define FILE _IO_FILE +#else /* ! USE_IN_LIBIO */ +# define PUT(f, s, n) fwrite (s, 1, n, f) +# define PAD(f, c, n) __printf_pad (f, c, n) +ssize_t __printf_pad __P ((FILE *, char pad, int n)); /* In vfprintf.c. */ +#endif /* USE_IN_LIBIO */ + +/* Macros for doing the actual output. */ + +#define outchar(ch) \ + do \ + { \ + register const int outc = (ch); \ + if (putc (outc, fp) == EOF) \ + return -1; \ + ++done; \ + } while (0) + +#define PRINT(ptr, len) \ + do \ + { \ + int outlen = (len); \ + const char *cp = (ptr); \ + while (outlen-- > 0) \ + outchar (*cp++); \ + } while (0) + +#define PADN(ch, len) \ + do \ + { \ + if (PAD (fp, ch, len) != len) \ + return -1; \ + done += len; \ + } \ + while (0) + + +int +__printf_fphex (FILE *fp, + const struct printf_info *info, + const void *const *args) +{ + /* The floating-point value to output. */ + union + { + union ieee754_double dbl; + union ieee854_long_double ldbl; + } + fpnum; + + /* Locale-dependent representation of decimal point. */ + wchar_t decimal; + + /* "NaN" or "Inf" for the special cases. */ + const char *special = NULL; + + /* Buffer for the generated number string for the mantissa. The + maximal size for the mantissa is 64 bits. */ + char numbuf[16]; + char *numstr; + char *numend; + int negative; + + /* The maximal exponent of two in decimal notation has 5 digits. */ + char expbuf[5]; + char *expstr; + int expnegative; + int exponent; + + /* Non-zero is mantissa is zero. */ + int zero_mantissa; + + /* The leading digit before the decimal point. */ + char leading; + + /* Precision. */ + int precision = info->prec; + + /* Width. */ + int width = info->width; + + /* Number of characters written. */ + int done = 0; + + + /* Figure out the decimal point character. */ + if (info->extra == 0) + { + if (mbtowc (&decimal, _NL_CURRENT (LC_NUMERIC, DECIMAL_POINT), + strlen (_NL_CURRENT (LC_NUMERIC, DECIMAL_POINT))) <= 0) + decimal = (wchar_t) *_NL_CURRENT (LC_NUMERIC, DECIMAL_POINT); + } + else + { + if (mbtowc (&decimal, _NL_CURRENT (LC_MONETARY, MON_DECIMAL_POINT), + strlen (_NL_CURRENT (LC_MONETARY, MON_DECIMAL_POINT))) <= 0) + decimal = (wchar_t) *_NL_CURRENT (LC_MONETARY, MON_DECIMAL_POINT); + } + /* Give default value. */ + if (decimal == L'\0') + decimal = L'.'; + + + /* Fetch the argument value. */ + if (info->is_long_double && sizeof (long double) > sizeof (double)) + { + fpnum.ldbl.d = *(const long double *) args[0]; + + /* Check for special values: not a number or infinity. */ + if (__isnanl (fpnum.ldbl.d)) + { + special = isupper (info->spec) ? "NAN" : "nan"; + negative = 0; + } + else + { + if (__isinfl (fpnum.ldbl.d)) + special = isupper (info->spec) ? "INF" : "inf"; + + negative = fpnum.ldbl.d < 0; + } + } + else + { + fpnum.dbl.d = *(const double *) args[0]; + + /* Check for special values: not a number or infinity. */ + if (__isnan (fpnum.dbl.d)) + { + special = isupper (info->spec) ? "NAN" : "nan"; + negative = 0; + } + else + { + if (__isinf (fpnum.dbl.d)) + special = isupper (info->spec) ? "INF" : "inf"; + + negative = fpnum.dbl.d < 0; + } + } + + if (special) + { + int width = info->prec > info->width ? info->prec : info->width; + + if (negative || info->showsign || info->space) + --width; + width -= 3; + + if (!info->left && width > 0) + PADN (' ', width); + + if (negative) + outchar ('-'); + else if (info->showsign) + outchar ('+'); + else if (info->space) + outchar (' '); + + PRINT (special, 3); + + if (info->left && width > 0) + PADN (' ', width); + + return done; + } + + /* We are handling here only 64 and 80 bit IEEE foating point + numbers. */ + if (info->is_long_double == 0 || sizeof (double) == sizeof (long double)) + { + /* We have 52 bits of mantissa plus one implicit digit. Since + 52 bits are representable without rest using hexadecimal + digits we use only the implicit digits for the number before + the decimal point. */ + if (sizeof (unsigned long int) > 6) + { + unsigned long int num; + + num = (((unsigned long int) fpnum.dbl.ieee.mantissa0) << 32 + | fpnum.dbl.ieee.mantissa1); + + zero_mantissa = num == 0; + + numstr = _itoa_word (num, numbuf + sizeof numbuf, 16, + info->spec == 'A'); + } + else + { + unsigned long long int num; + + num = (((unsigned long long int) fpnum.dbl.ieee.mantissa0) << 32 + | fpnum.dbl.ieee.mantissa1); + + zero_mantissa = num == 0; + + numstr = _itoa (num, numbuf + sizeof numbuf, 16, info->spec == 'A'); + } + + /* Fill with zeroes. */ + while (numstr > numbuf + (sizeof numbuf - 13)) /* 52 ÷ 4 = 13 */ + *--numstr = '0'; + + leading = fpnum.dbl.ieee.exponent == 0 ? '0' : '1'; + + exponent = fpnum.dbl.ieee.exponent; + + if (exponent != 0 && exponent < IEEE754_DOUBLE_BIAS) + { + expnegative = 1; + exponent = abs (exponent - IEEE754_DOUBLE_BIAS); + } + else + { + expnegative = 0; + if (exponent != 0) + exponent -= IEEE754_DOUBLE_BIAS; + } + } + else + { + /* The "strange" 80 bit format on ix86 and m68k has an explicit + leading digit in the 64 bit mantissa. */ + assert (sizeof (long double) == 12); + + if (sizeof (unsigned long int) > 6) + { + unsigned long int num; + + num = (((unsigned long int) fpnum.dbl.ieee.mantissa0) << 32 + | fpnum.dbl.ieee.mantissa1); + + zero_mantissa = num == 0; + + numstr = _itoa_word (num, numbuf + sizeof numbuf, 16, + info->spec == 'A'); + } + else + { + unsigned long long int num; + + num = (((unsigned long long int) fpnum.ldbl.ieee.mantissa0) << 32 + | fpnum.ldbl.ieee.mantissa1); + + zero_mantissa = num == 0; + + numstr = _itoa (num, numbuf + sizeof numbuf, 16, info->spec == 'A'); + } + + /* We use a full nibble for the leading digit. */ + leading = *numstr++; + + /* Fill with zeroes. */ + while (numstr > numbuf + (sizeof numbuf - 15)) /* 60 ÷ 4 = 15 */ + *--numstr = '0'; + + /* We have 3 bits from the mantissa in the leading nibble. */ + exponent = fpnum.ldbl.ieee.exponent - 3; + + if (exponent != 0 && exponent < IEEE854_LONG_DOUBLE_BIAS) + { + expnegative = 1; + exponent = abs (exponent - IEEE854_LONG_DOUBLE_BIAS); + } + else + { + expnegative = 0; + if (exponent != 0) + exponent -= IEEE854_LONG_DOUBLE_BIAS; + } + } + + /* Look for trailing zeroes. */ + if (! zero_mantissa) + { + numend = numbuf + sizeof numbuf; + while (numend[-1] == '0') + --numend; + + if (precision == -1) + precision = numend - numstr; + else if (precision < numend - numstr + && (numstr[precision] > 5 + || (numstr[precision] == 5 + && (precision + 1 < numend - numstr + /* Round to even. */ + || (precision > 0 + && ((numstr[precision - 1] & 1) + ^ (isdigit (numstr[precision - 1]) == 0))) + || (precision == 0 + && ((leading & 1) + ^ (isdigit (leading) == 0))))))) + { + /* Round up. */ + int cnt = precision; + while (--cnt >= 0) + { + char ch = numstr[cnt]; + /* We assume that the digits and the letters are ordered + like in ASCII. This is true for the rest of GNU, too. */ + if (ch == '9') + { + numstr[cnt] = info->spec; /* This is tricky, + think about it! */ + break; + } + else if (tolower (ch) < 'f') + { + ++numstr[cnt]; + break; + } + else + numstr[cnt] = '0'; + } + if (cnt < 0) + { + /* The mantissa so far was fff...f Now increment the + leading digit. Here it is again possible that we + get an overflow. */ + if (leading == '9') + leading = info->spec; + else if (tolower (leading) < 'f') + ++leading; + else + { + leading = 1; + if (expnegative) + { + exponent += 4; + if (exponent >= 0) + expnegative = 0; + } + else + exponent += 4; + } + } + } + } + else + numend = numstr; + + /* Now we can compute the exponent string. */ + expstr = _itoa_word (exponent, expbuf + sizeof expbuf, 10, 0); + + /* Now we have all information to compute the size. */ + width -= ((negative || info->showsign || info->space) + /* Sign. */ + + 2 + 1 + 1 + precision + 1 + 1 + /* 0x h . hhh P ExpoSign. */ + + ((expbuf + sizeof expbuf) - expstr)); + /* Exponent. */ + + /* A special case if when the mantissa is zero and the `#' is not + given. In this case we must not print the decimal point. */ + if (zero_mantissa && precision == 0 && !info->alt) + ++width; /* This nihilates the +1 for the decimal-point + character in the following equation. */ + + if (!info->left && width > 0) + PADN (' ', width); + + if (negative) + outchar ('-'); + else if (info->showsign) + outchar ('+'); + else if (info->space) + outchar (' '); + + outchar ('0'); + outchar (info->spec == 'A' ? 'X' : 'x'); + outchar (leading); + + if (!zero_mantissa || precision != 0 || info->alt) + outchar (decimal); + + if (!zero_mantissa || precision != 0) + { + PRINT (numstr, MIN (numend - numstr, precision)); + if (precision > numend - numstr) + PADN ('0', precision - (numend - numstr)); + } + + if (info->left && info->pad == '0' && width > 0) + PADN ('0', width); + + outchar (info->spec == 'A' ? 'P' : 'p'); + + outchar (expnegative ? '-' : '+'); + + PRINT (expstr, (expbuf + sizeof expbuf) - expstr); + + if (info->left && info->pad != '0' && width > 0) + PADN (info->pad, width); + + return done; +} |