Dogcows Code - chaz/tar/blob - lib/xstrtol.c

   1 /* A more useful interface to strtol.
   2    Copyright (C) 1995, 1996, 1998-2001 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by Jim Meyering. */
  19
  20 #if HAVE_CONFIG_H
  21 # include <config.h>
  22 #endif
  23
  24 #ifndef __strtol
  25 # define __strtol strtol
  26 # define __strtol_t long int
  27 # define __xstrtol xstrtol
  28 #endif
  29
  30 /* Some pre-ANSI implementations (e.g. SunOS 4)
  31    need stderr defined if assertion checking is enabled.  */
  32 #include <stdio.h>
  33
  34 #if STDC_HEADERS
  35 # include <stdlib.h>
  36 #endif
  37
  38 #if HAVE_STRING_H
  39 # include <string.h>
  40 #else
  41 # include <strings.h>
  42 # ifndef strchr
  43 #  define strchr index
  44 # endif
  45 #endif
  46
  47 #include <assert.h>
  48 #include <ctype.h>
  49
  50 #include <errno.h>
  51 #ifndef errno
  52 extern int errno;
  53 #endif
  54
  55 #if HAVE_LIMITS_H
  56 # include <limits.h>
  57 #endif
  58
  59 #ifndef CHAR_BIT
  60 # define CHAR_BIT 8
  61 #endif
  62
  63 /* The extra casts work around common compiler bugs.  */
  64 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
  65 /* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
  66    It is necessary at least when t == time_t.  */
  67 #define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
  68                               ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
  69 #define TYPE_MAXIMUM(t) (~ (t) 0 - TYPE_MINIMUM (t))
  70
  71 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
  72 # define IN_CTYPE_DOMAIN(c) 1
  73 #else
  74 # define IN_CTYPE_DOMAIN(c) isascii(c)
  75 #endif
  76
  77 #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
  78
  79 #include "xstrtol.h"
  80
  81 #if !HAVE_DECL_STRTOL && !defined strtol
  82 long int strtol ();
  83 #endif
  84
  85 #if !HAVE_DECL_STRTOUL && !defined strtoul
  86 unsigned long int strtoul ();
  87 #endif
  88
  89 #if !HAVE_DECL_STRTOIMAX && !defined strtoimax
  90 intmax_t strtoimax ();
  91 #endif
  92
  93 #if !HAVE_DECL_STRTOUMAX && !defined strtoumax
  94 uintmax_t strtoumax ();
  95 #endif
  96
  97 static int
  98 bkm_scale (__strtol_t *x, int scale_factor)
  99 {
 100   __strtol_t product = *x * scale_factor;
 101   if (*x != product / scale_factor)
 102     return 1;
 103   *x = product;
 104   return 0;
 105 }
 106
 107 static int
 108 bkm_scale_by_power (__strtol_t *x, int base, int power)
 109 {
 110   while (power--)
 111     if (bkm_scale (x, base))
 112       return 1;
 113
 114   return 0;
 115 }
 116
 117 /* FIXME: comment.  */
 118
 119 strtol_error
 120 __xstrtol (const char *s, char **ptr, int strtol_base,
 121            __strtol_t *val, const char *valid_suffixes)
 122 {
 123   char *t_ptr;
 124   char **p;
 125   __strtol_t tmp;
 126
 127   assert (0 <= strtol_base && strtol_base <= 36);
 128
 129   p = (ptr ? ptr : &t_ptr);
 130
 131   if (! TYPE_SIGNED (__strtol_t))
 132     {
 133       const char *q = s;
 134       while (ISSPACE ((unsigned char) *q))
 135         ++q;
 136       if (*q == '-')
 137         return LONGINT_INVALID;
 138     }
 139
 140   errno = 0;
 141   tmp = __strtol (s, p, strtol_base);
 142   if (errno != 0)
 143     return LONGINT_OVERFLOW;
 144   if (*p == s)
 145     return LONGINT_INVALID;
 146
 147   /* Let valid_suffixes == NULL mean `allow any suffix'.  */
 148   /* FIXME: update all callers except the ones that allow suffixes
 149      after the number, changing last parameter NULL to `""'.  */
 150   if (!valid_suffixes)
 151     {
 152       *val = tmp;
 153       return LONGINT_OK;
 154     }
 155
 156   if (**p != '\0')
 157     {
 158       int base = 1024;
 159       int suffixes = 1;
 160       int overflow;
 161
 162       if (!strchr (valid_suffixes, **p))
 163         {
 164           *val = tmp;
 165           return LONGINT_INVALID_SUFFIX_CHAR;
 166         }
 167
 168       if (strchr (valid_suffixes, '0'))
 169         {
 170           /* The ``valid suffix'' '0' is a special flag meaning that
 171              an optional second suffix is allowed, which can change
 172              the base, e.g. "100MD" for 100 megabytes decimal.  */
 173
 174           switch (p[0][1])
 175             {
 176             case 'B':
 177               suffixes++;
 178               break;
 179
 180             case 'D':
 181               base = 1000;
 182               suffixes++;
 183               break;
 184             }
 185         }
 186
 187       switch (**p)
 188         {
 189         case 'b':
 190           overflow = bkm_scale (&tmp, 512);
 191           break;
 192
 193         case 'B':
 194           overflow = bkm_scale (&tmp, 1024);
 195           break;
 196
 197         case 'c':
 198           overflow = 0;
 199           break;
 200
 201         case 'E': /* Exa */
 202           overflow = bkm_scale_by_power (&tmp, base, 6);
 203           break;
 204
 205         case 'G': /* Giga */
 206         case 'g': /* 'g' is undocumented; for compatibility only */
 207           overflow = bkm_scale_by_power (&tmp, base, 3);
 208           break;
 209
 210         case 'k': /* kilo */
 211           overflow = bkm_scale_by_power (&tmp, base, 1);
 212           break;
 213
 214         case 'M': /* Mega */
 215         case 'm': /* 'm' is undocumented; for compatibility only */
 216           overflow = bkm_scale_by_power (&tmp, base, 2);
 217           break;
 218
 219         case 'P': /* Peta */
 220           overflow = bkm_scale_by_power (&tmp, base, 5);
 221           break;
 222
 223         case 'T': /* Tera */
 224         case 't': /* 't' is undocumented; for compatibility only */
 225           overflow = bkm_scale_by_power (&tmp, base, 4);
 226           break;
 227
 228         case 'w':
 229           overflow = bkm_scale (&tmp, 2);
 230           break;
 231
 232         case 'Y': /* Yotta */
 233           overflow = bkm_scale_by_power (&tmp, base, 8);
 234           break;
 235
 236         case 'Z': /* Zetta */
 237           overflow = bkm_scale_by_power (&tmp, base, 7);
 238           break;
 239
 240         default:
 241           *val = tmp;
 242           return LONGINT_INVALID_SUFFIX_CHAR;
 243           break;
 244         }
 245
 246       if (overflow)
 247         return LONGINT_OVERFLOW;
 248
 249       (*p) += suffixes;
 250     }
 251
 252   *val = tmp;
 253   return LONGINT_OK;
 254 }
 255
 256 #ifdef TESTING_XSTRTO
 257
 258 # include <stdio.h>
 259 # include "error.h"
 260
 261 char *program_name;
 262
 263 int
 264 main (int argc, char** argv)
 265 {
 266   strtol_error s_err;
 267   int i;
 268
 269   program_name = argv[0];
 270   for (i=1; i<argc; i++)
 271     {
 272       char *p;
 273       __strtol_t val;
 274
 275       s_err = __xstrtol (argv[i], &p, 0, &val, "bckmw");
 276       if (s_err == LONGINT_OK)
 277         {
 278           printf ("%s->%lu (%s)\n", argv[i], val, p);
 279         }
 280       else
 281         {
 282           STRTOL_FATAL_ERROR (argv[i], "arg", s_err);
 283         }
 284     }
 285   exit (0);
 286 }
 287
 288 #endif /* TESTING_XSTRTO */