lib/xstrtol.c

   1 /* A more useful interface to strtol.
   2
   3    Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2003 Free
   4    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 # define STRTOL_T_MINIMUM LONG_MIN
  31 # define STRTOL_T_MAXIMUM LONG_MAX
  32 #endif
  33
  34 /* Some pre-ANSI implementations (e.g. SunOS 4)
  35    need stderr defined if assertion checking is enabled.  */
  36 #include <stdio.h>
  37
  38 #include <assert.h>
  39 #include <ctype.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 #include <errno.h>
  44 #ifndef errno
  45 extern int errno;
  46 #endif
  47
  48 #include <limits.h>
  49
  50 /* The extra casts work around common compiler bugs.  */
  51 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  52 #define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
  53                               ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) \
  54                               : (t) 0))
  55 #define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
  56
  57 #ifndef STRTOL_T_MINIMUM
  58 # define STRTOL_T_MINIMUM TYPE_MINIMUM (__strtol_t)
  59 # define STRTOL_T_MAXIMUM TYPE_MAXIMUM (__strtol_t)
  60 #endif
  61
  62 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
  63 # define IN_CTYPE_DOMAIN(c) 1
  64 #else
  65 # define IN_CTYPE_DOMAIN(c) isascii(c)
  66 #endif
  67
  68 #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
  69
  70 #include "xstrtol.h"
  71
  72 #if !HAVE_DECL_STRTOIMAX && !defined strtoimax
  73 intmax_t strtoimax ();
  74 #endif
  75
  76 #if !HAVE_DECL_STRTOUMAX && !defined strtoumax
  77 uintmax_t strtoumax ();
  78 #endif
  79
  80 static strtol_error
  81 bkm_scale (__strtol_t *x, int scale_factor)
  82 {
  83   if (TYPE_SIGNED (__strtol_t) && *x < STRTOL_T_MINIMUM / scale_factor)
  84     {
  85       *x = STRTOL_T_MINIMUM;
  86       return LONGINT_OVERFLOW;
  87     }
  88   if (STRTOL_T_MAXIMUM / scale_factor < *x)
  89     {
  90       *x = STRTOL_T_MAXIMUM;
  91       return LONGINT_OVERFLOW;
  92     }
  93   *x *= scale_factor;
  94   return LONGINT_OK;
  95 }
  96
  97 static strtol_error
  98 bkm_scale_by_power (__strtol_t *x, int base, int power)
  99 {
 100   strtol_error err = LONGINT_OK;
 101   while (power--)
 102     err |= bkm_scale (x, base);
 103   return err;
 104 }
 105
 106 /* FIXME: comment.  */
 107
 108 strtol_error
 109 __xstrtol (const char *s, char **ptr, int strtol_base,
 110            __strtol_t *val, const char *valid_suffixes)
 111 {
 112   char *t_ptr;
 113   char **p;
 114   __strtol_t tmp;
 115   strtol_error err = LONGINT_OK;
 116
 117   assert (0 <= strtol_base && strtol_base <= 36);
 118
 119   p = (ptr ? ptr : &t_ptr);
 120
 121   if (! TYPE_SIGNED (__strtol_t))
 122     {
 123       const char *q = s;
 124       while (ISSPACE ((unsigned char) *q))
 125         ++q;
 126       if (*q == '-')
 127         return LONGINT_INVALID;
 128     }
 129
 130   errno = 0;
 131   tmp = __strtol (s, p, strtol_base);
 132
 133   if (*p == s)
 134     {
 135       /* If there is no number but there is a valid suffix, assume the
 136          number is 1.  The string is invalid otherwise.  */
 137       if (valid_suffixes && **p && strchr (valid_suffixes, **p))
 138         tmp = 1;
 139       else
 140         return LONGINT_INVALID;
 141     }
 142   else if (errno != 0)
 143     {
 144       if (errno != ERANGE)
 145         return LONGINT_INVALID;
 146       err = LONGINT_OVERFLOW;
 147     }
 148
 149   /* Let valid_suffixes == NULL mean `allow any suffix'.  */
 150   /* FIXME: update all callers except the ones that allow suffixes
 151      after the number, changing last parameter NULL to `""'.  */
 152   if (!valid_suffixes)
 153     {
 154       *val = tmp;
 155       return err;
 156     }
 157
 158   if (**p != '\0')
 159     {
 160       int base = 1024;
 161       int suffixes = 1;
 162       strtol_error overflow;
 163
 164       if (!strchr (valid_suffixes, **p))
 165         {
 166           *val = tmp;
 167           return err | LONGINT_INVALID_SUFFIX_CHAR;
 168         }
 169
 170       if (strchr (valid_suffixes, '0'))
 171         {
 172           /* The ``valid suffix'' '0' is a special flag meaning that
 173              an optional second suffix is allowed, which can change
 174              the base.  A suffix "B" (e.g. "100MB") stands for a power
 175              of 1000, whereas a suffix "iB" (e.g. "100MiB") stands for
 176              a power of 1024.  If no suffix (e.g. "100M"), assume
 177              power-of-1024.  */
 178
 179           switch (p[0][1])
 180             {
 181             case 'i':
 182               if (p[0][2] == 'B')
 183                 suffixes += 2;
 184               break;
 185
 186             case 'B':
 187             case 'D': /* 'D' is obsolescent */
 188               base = 1000;
 189               suffixes++;
 190               break;
 191             }
 192         }
 193
 194       switch (**p)
 195         {
 196         case 'b':
 197           overflow = bkm_scale (&tmp, 512);
 198           break;
 199
 200         case 'B':
 201           overflow = bkm_scale (&tmp, 1024);
 202           break;
 203
 204         case 'c':
 205           overflow = 0;
 206           break;
 207
 208         case 'E': /* exa or exbi */
 209           overflow = bkm_scale_by_power (&tmp, base, 6);
 210           break;
 211
 212         case 'G': /* giga or gibi */
 213         case 'g': /* 'g' is undocumented; for compatibility only */
 214           overflow = bkm_scale_by_power (&tmp, base, 3);
 215           break;
 216
 217         case 'k': /* kilo */
 218         case 'K': /* kibi */
 219           overflow = bkm_scale_by_power (&tmp, base, 1);
 220           break;
 221
 222         case 'M': /* mega or mebi */
 223         case 'm': /* 'm' is undocumented; for compatibility only */
 224           overflow = bkm_scale_by_power (&tmp, base, 2);
 225           break;
 226
 227         case 'P': /* peta or pebi */
 228           overflow = bkm_scale_by_power (&tmp, base, 5);
 229           break;
 230
 231         case 'T': /* tera or tebi */
 232         case 't': /* 't' is undocumented; for compatibility only */
 233           overflow = bkm_scale_by_power (&tmp, base, 4);
 234           break;
 235
 236         case 'w':
 237           overflow = bkm_scale (&tmp, 2);
 238           break;
 239
 240         case 'Y': /* yotta or 2**80 */
 241           overflow = bkm_scale_by_power (&tmp, base, 8);
 242           break;
 243
 244         case 'Z': /* zetta or 2**70 */
 245           overflow = bkm_scale_by_power (&tmp, base, 7);
 246           break;
 247
 248         default:
 249           *val = tmp;
 250           return err | LONGINT_INVALID_SUFFIX_CHAR;
 251         }
 252
 253       err |= overflow;
 254       *p += suffixes;
 255       if (**p)
 256         err |= LONGINT_INVALID_SUFFIX_CHAR;
 257     }
 258
 259   *val = tmp;
 260   return err;
 261 }
 262
 263 #ifdef TESTING_XSTRTO
 264
 265 # include <stdio.h>
 266 # include "error.h"
 267
 268 char *program_name;
 269
 270 int
 271 main (int argc, char **argv)
 272 {
 273   strtol_error s_err;
 274   int i;
 275
 276   program_name = argv[0];
 277   for (i=1; i<argc; i++)
 278     {
 279       char *p;
 280       __strtol_t val;
 281
 282       s_err = __xstrtol (argv[i], &p, 0, &val, "bckmw");
 283       if (s_err == LONGINT_OK)
 284         {
 285           printf ("%s->%lu (%s)\n", argv[i], val, p);
 286         }
 287       else
 288         {
 289           STRTOL_FATAL_ERROR (argv[i], "arg", s_err);
 290         }
 291     }
 292   exit (0);
 293 }
 294
 295 #endif /* TESTING_XSTRTO */