gdb/common/common-utils.c

   1 /* Shared general utility routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2016 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "common-defs.h"
  21 #include "host-defs.h"
  22 #include <ctype.h>
  23
  24 /* The xmalloc() (libiberty.h) family of memory management routines.
  25
  26    These are like the ISO-C malloc() family except that they implement
  27    consistent semantics and guard against typical memory management
  28    problems.  */
  29
  30 /* NOTE: These are declared using PTR to ensure consistency with
  31    "libiberty.h".  xfree() is GDB local.  */
  32
  33 PTR                            /* ARI: PTR */
  34 xmalloc (size_t size)
  35 {
  36   void *val;
  37
  38   /* See libiberty/xmalloc.c.  This function need's to match that's
  39      semantics.  It never returns NULL.  */
  40   if (size == 0)
  41     size = 1;
  42
  43   val = malloc (size);         /* ARI: malloc */
  44   if (val == NULL)
  45     malloc_failure (size);
  46
  47   return val;
  48 }
  49
  50 PTR                              /* ARI: PTR */
  51 xrealloc (PTR ptr, size_t size)          /* ARI: PTR */
  52 {
  53   void *val;
  54
  55   /* See libiberty/xmalloc.c.  This function need's to match that's
  56      semantics.  It never returns NULL.  */
  57   if (size == 0)
  58     size = 1;
  59
  60   if (ptr != NULL)
  61     val = realloc (ptr, size);  /* ARI: realloc */
  62   else
  63     val = malloc (size);                /* ARI: malloc */
  64   if (val == NULL)
  65     malloc_failure (size);
  66
  67   return val;
  68 }
  69
  70 PTR                            /* ARI: PTR */
  71 xcalloc (size_t number, size_t size)
  72 {
  73   void *mem;
  74
  75   /* See libiberty/xmalloc.c.  This function need's to match that's
  76      semantics.  It never returns NULL.  */
  77   if (number == 0 || size == 0)
  78     {
  79       number = 1;
  80       size = 1;
  81     }
  82
  83   mem = calloc (number, size);      /* ARI: xcalloc */
  84   if (mem == NULL)
  85     malloc_failure (number * size);
  86
  87   return mem;
  88 }
  89
  90 void *
  91 xzalloc (size_t size)
  92 {
  93   return xcalloc (1, size);
  94 }
  95
  96 void
  97 xfree (void *ptr)
  98 {
  99   if (ptr != NULL)
 100     free (ptr);         /* ARI: free */
 101 }
 102
 103 void
 104 xmalloc_failed (size_t size)
 105 {
 106   malloc_failure (size);
 107 }
 108
 109 /* Like asprintf/vasprintf but get an internal_error if the call
 110    fails. */
 111
 112 char *
 113 xstrprintf (const char *format, ...)
 114 {
 115   char *ret;
 116   va_list args;
 117
 118   va_start (args, format);
 119   ret = xstrvprintf (format, args);
 120   va_end (args);
 121   return ret;
 122 }
 123
 124 char *
 125 xstrvprintf (const char *format, va_list ap)
 126 {
 127   char *ret = NULL;
 128   int status = vasprintf (&ret, format, ap);
 129
 130   /* NULL is returned when there was a memory allocation problem, or
 131      any other error (for instance, a bad format string).  A negative
 132      status (the printed length) with a non-NULL buffer should never
 133      happen, but just to be sure.  */
 134   if (ret == NULL || status < 0)
 135     internal_error (__FILE__, __LINE__, _("vasprintf call failed"));
 136   return ret;
 137 }
 138
 139 int
 140 xsnprintf (char *str, size_t size, const char *format, ...)
 141 {
 142   va_list args;
 143   int ret;
 144
 145   va_start (args, format);
 146   ret = vsnprintf (str, size, format, args);
 147   gdb_assert (ret < size);
 148   va_end (args);
 149
 150   return ret;
 151 }
 152
 153 char *
 154 savestring (const char *ptr, size_t len)
 155 {
 156   char *p = (char *) xmalloc (len + 1);
 157
 158   memcpy (p, ptr, len);
 159   p[len] = 0;
 160   return p;
 161 }
 162
 163 /* The bit offset of the highest byte in a ULONGEST, for overflow
 164    checking.  */
 165
 166 #define HIGH_BYTE_POSN ((sizeof (ULONGEST) - 1) * HOST_CHAR_BIT)
 167
 168 /* True (non-zero) iff DIGIT is a valid digit in radix BASE,
 169    where 2 <= BASE <= 36.  */
 170
 171 static int
 172 is_digit_in_base (unsigned char digit, int base)
 173 {
 174   if (!isalnum (digit))
 175     return 0;
 176   if (base <= 10)
 177     return (isdigit (digit) && digit < base + '0');
 178   else
 179     return (isdigit (digit) || tolower (digit) < base - 10 + 'a');
 180 }
 181
 182 static int
 183 digit_to_int (unsigned char c)
 184 {
 185   if (isdigit (c))
 186     return c - '0';
 187   else
 188     return tolower (c) - 'a' + 10;
 189 }
 190
 191 /* As for strtoul, but for ULONGEST results.  */
 192
 193 ULONGEST
 194 strtoulst (const char *num, const char **trailer, int base)
 195 {
 196   unsigned int high_part;
 197   ULONGEST result;
 198   int minus = 0;
 199   int i = 0;
 200
 201   /* Skip leading whitespace.  */
 202   while (isspace (num[i]))
 203     i++;
 204
 205   /* Handle prefixes.  */
 206   if (num[i] == '+')
 207     i++;
 208   else if (num[i] == '-')
 209     {
 210       minus = 1;
 211       i++;
 212     }
 213
 214   if (base == 0 || base == 16)
 215     {
 216       if (num[i] == '0' && (num[i + 1] == 'x' || num[i + 1] == 'X'))
 217         {
 218           i += 2;
 219           if (base == 0)
 220             base = 16;
 221         }
 222     }
 223
 224   if (base == 0 && num[i] == '0')
 225     base = 8;
 226
 227   if (base == 0)
 228     base = 10;
 229
 230   if (base < 2 || base > 36)
 231     {
 232       errno = EINVAL;
 233       return 0;
 234     }
 235
 236   result = high_part = 0;
 237   for (; is_digit_in_base (num[i], base); i += 1)
 238     {
 239       result = result * base + digit_to_int (num[i]);
 240       high_part = high_part * base + (unsigned int) (result >> HIGH_BYTE_POSN);
 241       result &= ((ULONGEST) 1 << HIGH_BYTE_POSN) - 1;
 242       if (high_part > 0xff)
 243         {
 244           errno = ERANGE;
 245           result = ~ (ULONGEST) 0;
 246           high_part = 0;
 247           minus = 0;
 248           break;
 249         }
 250     }
 251
 252   if (trailer != NULL)
 253     *trailer = &num[i];
 254
 255   result = result + ((ULONGEST) high_part << HIGH_BYTE_POSN);
 256   if (minus)
 257     return -result;
 258   else
 259     return result;
 260 }
 261
 262 /* See documentation in common-utils.h.  */
 263
 264 char *
 265 skip_spaces (char *chp)
 266 {
 267   if (chp == NULL)
 268     return NULL;
 269   while (*chp && isspace (*chp))
 270     chp++;
 271   return chp;
 272 }
 273
 274 /* A const-correct version of the above.  */
 275
 276 const char *
 277 skip_spaces_const (const char *chp)
 278 {
 279   if (chp == NULL)
 280     return NULL;
 281   while (*chp && isspace (*chp))
 282     chp++;
 283   return chp;
 284 }
 285
 286 /* See documentation in common-utils.h.  */
 287
 288 const char *
 289 skip_to_space_const (const char *chp)
 290 {
 291   if (chp == NULL)
 292     return NULL;
 293   while (*chp && !isspace (*chp))
 294     chp++;
 295   return chp;
 296 }