gnu/dist/diffutils/lib/xstrtol.c

   1 /*      $NetBSD$        */
   2
   3 /* A more useful interface to strtol.
   4    Copyright (C) 1995, 1996, 1998-2001 Free Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 /* Written by Jim Meyering. */
  21
  22 #if HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #ifndef __strtol
  27 # define __strtol strtol
  28 # define __strtol_t long int
  29 # define __xstrtol xstrtol
  30 #endif
  31
  32 /* Some pre-ANSI implementations (e.g. SunOS 4)
  33    need stderr defined if assertion checking is enabled.  */
  34 #include <stdio.h>
  35
  36 #if STDC_HEADERS
  37 # include <stdlib.h>
  38 #endif
  39
  40 #if HAVE_STRING_H
  41 # include <string.h>
  42 #else
  43 # include <strings.h>
  44 # ifndef strchr
  45 #  define strchr index
  46 # endif
  47 #endif
  48
  49 #include <assert.h>
  50 #include <ctype.h>
  51
  52 #include <errno.h>
  53 #ifndef errno
  54 extern int errno;
  55 #endif
  56
  57 #if HAVE_LIMITS_H
  58 # include <limits.h>
  59 #endif
  60
  61 #ifndef CHAR_BIT
  62 # define CHAR_BIT 8
  63 #endif
  64
  65 /* The extra casts work around common compiler bugs.  */
  66 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  67 /* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
  68    It is necessary at least when t == time_t.  */
  69 #define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
  70                               ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
  71 #define TYPE_MAXIMUM(t) (~ (t) 0 - TYPE_MINIMUM (t))
  72
  73 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
  74 # define IN_CTYPE_DOMAIN(c) 1
  75 #else
  76 # define IN_CTYPE_DOMAIN(c) isascii(c)
  77 #endif
  78
  79 #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
  80
  81 #include "xstrtol.h"
  82
  83 #if !HAVE_DECL_STRTOL && !defined strtol
  84 long int strtol ();
  85 #endif
  86
  87 #if !HAVE_DECL_STRTOUL && !defined strtoul
  88 unsigned long int strtoul ();
  89 #endif
  90
  91 #if !HAVE_DECL_STRTOIMAX && !defined strtoimax
  92 intmax_t strtoimax ();
  93 #endif
  94
  95 #if !HAVE_DECL_STRTOUMAX && !defined strtoumax
  96 uintmax_t strtoumax ();
  97 #endif
  98
  99 static int
 100 bkm_scale (__strtol_t *x, int scale_factor)
 101 {
 102   __strtol_t product = *x * scale_factor;
 103   if (*x != product / scale_factor)
 104     return 1;
 105   *x = product;
 106   return 0;
 107 }
 108
 109 static int
 110 bkm_scale_by_power (__strtol_t *x, int base, int power)
 111 {
 112   while (power--)
 113     if (bkm_scale (x, base))
 114       return 1;
 115
 116   return 0;
 117 }
 118
 119 /* FIXME: comment.  */
 120
 121 strtol_error
 122 __xstrtol (const char *s, char **ptr, int strtol_base,
 123            __strtol_t *val, const char *valid_suffixes)
 124 {
 125   char *t_ptr;
 126   char **p;
 127   __strtol_t tmp;
 128
 129   assert (0 <= strtol_base && strtol_base <= 36);
 130
 131   p = (ptr ? ptr : &t_ptr);
 132
 133   if (! TYPE_SIGNED (__strtol_t))
 134     {
 135       const char *q = s;
 136       while (ISSPACE ((unsigned char) *q))
 137         ++q;
 138       if (*q == '-')
 139         return LONGINT_INVALID;
 140     }
 141
 142   errno = 0;
 143   tmp = __strtol (s, p, strtol_base);
 144   if (errno != 0)
 145     return LONGINT_OVERFLOW;
 146
 147   if (*p == s)
 148     {
 149       /* If there is no number but there is a valid suffix, assume the
 150          number is 1.  The string is invalid otherwise.  */
 151       if (valid_suffixes && **p && strchr (valid_suffixes, **p))
 152         tmp = 1;
 153       else
 154         return LONGINT_INVALID;
 155     }
 156
 157   /* Let valid_suffixes == NULL mean `allow any suffix'.  */
 158   /* FIXME: update all callers except the ones that allow suffixes
 159      after the number, changing last parameter NULL to `""'.  */
 160   if (!valid_suffixes)
 161     {
 162       *val = tmp;
 163       return LONGINT_OK;
 164     }
 165
 166   if (**p != '\0')
 167     {
 168       int base = 1024;
 169       int suffixes = 1;
 170       int overflow;
 171
 172       if (!strchr (valid_suffixes, **p))
 173         {
 174           *val = tmp;
 175           return LONGINT_INVALID_SUFFIX_CHAR;
 176         }
 177
 178       if (strchr (valid_suffixes, '0'))
 179         {
 180           /* The ``valid suffix'' '0' is a special flag meaning that
 181              an optional second suffix is allowed, which can change
 182              the base.  A suffix "B" (e.g. "100MB") stands for a power
 183              of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for
 184              a power of 1024.  If no suffix (e.g. "100M"), assume
 185              power-of-1024.  */
 186
 187           switch (p[0][1])
 188             {
 189             case 'i':
 190               if (p[0][2] == 'B')
 191                 suffixes += 2;
 192               break;
 193
 194             case 'B':
 195             case 'D': /* 'D' is obsolescent */
 196               base = 1000;
 197               suffixes++;
 198               break;
 199             }
 200         }
 201
 202       switch (**p)
 203         {
 204         case 'b':
 205           overflow = bkm_scale (&tmp, 512);
 206           break;
 207
 208         case 'B':
 209           overflow = bkm_scale (&tmp, 1024);
 210           break;
 211
 212         case 'c':
 213           overflow = 0;
 214           break;
 215
 216         case 'E': /* exa or exbi */
 217           overflow = bkm_scale_by_power (&tmp, base, 6);
 218           break;
 219
 220         case 'G': /* giga or gibi */
 221         case 'g': /* 'g' is undocumented; for compatibility only */
 222           overflow = bkm_scale_by_power (&tmp, base, 3);
 223           break;
 224
 225         case 'k': /* kilo */
 226         case 'K': /* kibi */
 227           overflow = bkm_scale_by_power (&tmp, base, 1);
 228           break;
 229
 230         case 'M': /* mega or mebi */
 231         case 'm': /* 'm' is undocumented; for compatibility only */
 232           overflow = bkm_scale_by_power (&tmp, base, 2);
 233           break;
 234
 235         case 'P': /* peta or pebi */
 236           overflow = bkm_scale_by_power (&tmp, base, 5);
 237           break;
 238
 239         case 'T': /* tera or tebi */
 240         case 't': /* 't' is undocumented; for compatibility only */
 241           overflow = bkm_scale_by_power (&tmp, base, 4);
 242           break;
 243
 244         case 'w':
 245           overflow = bkm_scale (&tmp, 2);
 246           break;
 247
 248         case 'Y': /* yotta or 2**80 */
 249           overflow = bkm_scale_by_power (&tmp, base, 8);
 250           break;
 251
 252         case 'Z': /* zetta or 2**70 */
 253           overflow = bkm_scale_by_power (&tmp, base, 7);
 254           break;
 255
 256         default:
 257           *val = tmp;
 258           return LONGINT_INVALID_SUFFIX_CHAR;
 259           break;
 260         }
 261
 262       if (overflow)
 263         return LONGINT_OVERFLOW;
 264
 265       (*p) += suffixes;
 266     }
 267
 268   *val = tmp;
 269   return LONGINT_OK;
 270 }
 271
 272 #ifdef TESTING_XSTRTO
 273
 274 # include <stdio.h>
 275 # include "error.h"
 276
 277 char *program_name;
 278
 279 int
 280 main (int argc, char** argv)
 281 {
 282   strtol_error s_err;
 283   int i;
 284
 285   program_name = argv[0];
 286   for (i=1; i<argc; i++)
 287     {
 288       char *p;
 289       __strtol_t val;
 290
 291       s_err = __xstrtol (argv[i], &p, 0, &val, "bckmw");
 292       if (s_err == LONGINT_OK)
 293         {
 294           printf ("%s->%lu (%s)\n", argv[i], val, p);
 295         }
 296       else
 297         {
 298           STRTOL_FATAL_ERROR (argv[i], "arg", s_err);
 299         }
 300     }
 301   exit (0);
 302 }
 303
 304 #endif /* TESTING_XSTRTO */