gdb/common/common-utils.c

   1 /* Shared general utility routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2017 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 "common-utils.h"
  22 #include "host-defs.h"
  23 #include <ctype.h>
  24
  25 /* The xmalloc() (libiberty.h) family of memory management routines.
  26
  27    These are like the ISO-C malloc() family except that they implement
  28    consistent semantics and guard against typical memory management
  29    problems.  */
  30
  31 /* NOTE: These are declared using PTR to ensure consistency with
  32    "libiberty.h".  xfree() is GDB local.  */
  33
  34 PTR                            /* ARI: PTR */
  35 xmalloc (size_t size)
  36 {
  37   void *val;
  38
  39   /* See libiberty/xmalloc.c.  This function need's to match that's
  40      semantics.  It never returns NULL.  */
  41   if (size == 0)
  42     size = 1;
  43
  44   val = malloc (size);         /* ARI: malloc */
  45   if (val == NULL)
  46     malloc_failure (size);
  47
  48   return val;
  49 }
  50
  51 PTR                              /* ARI: PTR */
  52 xrealloc (PTR ptr, size_t size)          /* ARI: PTR */
  53 {
  54   void *val;
  55
  56   /* See libiberty/xmalloc.c.  This function need's to match that's
  57      semantics.  It never returns NULL.  */
  58   if (size == 0)
  59     size = 1;
  60
  61   if (ptr != NULL)
  62     val = realloc (ptr, size);  /* ARI: realloc */
  63   else
  64     val = malloc (size);                /* ARI: malloc */
  65   if (val == NULL)
  66     malloc_failure (size);
  67
  68   return val;
  69 }
  70
  71 PTR                            /* ARI: PTR */
  72 xcalloc (size_t number, size_t size)
  73 {
  74   void *mem;
  75
  76   /* See libiberty/xmalloc.c.  This function need's to match that's
  77      semantics.  It never returns NULL.  */
  78   if (number == 0 || size == 0)
  79     {
  80       number = 1;
  81       size = 1;
  82     }
  83
  84   mem = calloc (number, size);      /* ARI: xcalloc */
  85   if (mem == NULL)
  86     malloc_failure (number * size);
  87
  88   return mem;
  89 }
  90
  91 void *
  92 xzalloc (size_t size)
  93 {
  94   return xcalloc (1, size);
  95 }
  96
  97 void
  98 xfree (void *ptr)
  99 {
 100   if (ptr != NULL)
 101     free (ptr);         /* ARI: free */
 102 }
 103
 104 void
 105 xmalloc_failed (size_t size)
 106 {
 107   malloc_failure (size);
 108 }
 109
 110 /* Like asprintf/vasprintf but get an internal_error if the call
 111    fails. */
 112
 113 char *
 114 xstrprintf (const char *format, ...)
 115 {
 116   char *ret;
 117   va_list args;
 118
 119   va_start (args, format);
 120   ret = xstrvprintf (format, args);
 121   va_end (args);
 122   return ret;
 123 }
 124
 125 char *
 126 xstrvprintf (const char *format, va_list ap)
 127 {
 128   char *ret = NULL;
 129   int status = vasprintf (&ret, format, ap);
 130
 131   /* NULL is returned when there was a memory allocation problem, or
 132      any other error (for instance, a bad format string).  A negative
 133      status (the printed length) with a non-NULL buffer should never
 134      happen, but just to be sure.  */
 135   if (ret == NULL || status < 0)
 136     internal_error (__FILE__, __LINE__, _("vasprintf call failed"));
 137   return ret;
 138 }
 139
 140 int
 141 xsnprintf (char *str, size_t size, const char *format, ...)
 142 {
 143   va_list args;
 144   int ret;
 145
 146   va_start (args, format);
 147   ret = vsnprintf (str, size, format, args);
 148   gdb_assert (ret < size);
 149   va_end (args);
 150
 151   return ret;
 152 }
 153
 154 /* See documentation in common-utils.h.  */
 155
 156 std::string
 157 string_printf (const char* fmt, ...)
 158 {
 159   va_list vp;
 160   int size;
 161
 162   va_start (vp, fmt);
 163   size = vsnprintf (NULL, 0, fmt, vp);
 164   va_end (vp);
 165
 166   std::string str (size, '\0');
 167
 168   /* C++11 and later guarantee std::string uses contiguous memory and
 169      always includes the terminating '\0'.  */
 170   va_start (vp, fmt);
 171   vsprintf (&str[0], fmt, vp);
 172   va_end (vp);
 173
 174   return str;
 175 }
 176
 177 char *
 178 savestring (const char *ptr, size_t len)
 179 {
 180   char *p = (char *) xmalloc (len + 1);
 181
 182   memcpy (p, ptr, len);
 183   p[len] = 0;
 184   return p;
 185 }
 186
 187 /* The bit offset of the highest byte in a ULONGEST, for overflow
 188    checking.  */
 189
 190 #define HIGH_BYTE_POSN ((sizeof (ULONGEST) - 1) * HOST_CHAR_BIT)
 191
 192 /* True (non-zero) iff DIGIT is a valid digit in radix BASE,
 193    where 2 <= BASE <= 36.  */
 194
 195 static int
 196 is_digit_in_base (unsigned char digit, int base)
 197 {
 198   if (!isalnum (digit))
 199     return 0;
 200   if (base <= 10)
 201     return (isdigit (digit) && digit < base + '0');
 202   else
 203     return (isdigit (digit) || tolower (digit) < base - 10 + 'a');
 204 }
 205
 206 static int
 207 digit_to_int (unsigned char c)
 208 {
 209   if (isdigit (c))
 210     return c - '0';
 211   else
 212     return tolower (c) - 'a' + 10;
 213 }
 214
 215 /* As for strtoul, but for ULONGEST results.  */
 216
 217 ULONGEST
 218 strtoulst (const char *num, const char **trailer, int base)
 219 {
 220   unsigned int high_part;
 221   ULONGEST result;
 222   int minus = 0;
 223   int i = 0;
 224
 225   /* Skip leading whitespace.  */
 226   while (isspace (num[i]))
 227     i++;
 228
 229   /* Handle prefixes.  */
 230   if (num[i] == '+')
 231     i++;
 232   else if (num[i] == '-')
 233     {
 234       minus = 1;
 235       i++;
 236     }
 237
 238   if (base == 0 || base == 16)
 239     {
 240       if (num[i] == '0' && (num[i + 1] == 'x' || num[i + 1] == 'X'))
 241         {
 242           i += 2;
 243           if (base == 0)
 244             base = 16;
 245         }
 246     }
 247
 248   if (base == 0 && num[i] == '0')
 249     base = 8;
 250
 251   if (base == 0)
 252     base = 10;
 253
 254   if (base < 2 || base > 36)
 255     {
 256       errno = EINVAL;
 257       return 0;
 258     }
 259
 260   result = high_part = 0;
 261   for (; is_digit_in_base (num[i], base); i += 1)
 262     {
 263       result = result * base + digit_to_int (num[i]);
 264       high_part = high_part * base + (unsigned int) (result >> HIGH_BYTE_POSN);
 265       result &= ((ULONGEST) 1 << HIGH_BYTE_POSN) - 1;
 266       if (high_part > 0xff)
 267         {
 268           errno = ERANGE;
 269           result = ~ (ULONGEST) 0;
 270           high_part = 0;
 271           minus = 0;
 272           break;
 273         }
 274     }
 275
 276   if (trailer != NULL)
 277     *trailer = &num[i];
 278
 279   result = result + ((ULONGEST) high_part << HIGH_BYTE_POSN);
 280   if (minus)
 281     return -result;
 282   else
 283     return result;
 284 }
 285
 286 /* See documentation in common-utils.h.  */
 287
 288 char *
 289 skip_spaces (char *chp)
 290 {
 291   if (chp == NULL)
 292     return NULL;
 293   while (*chp && isspace (*chp))
 294     chp++;
 295   return chp;
 296 }
 297
 298 /* A const-correct version of the above.  */
 299
 300 const char *
 301 skip_spaces_const (const char *chp)
 302 {
 303   if (chp == NULL)
 304     return NULL;
 305   while (*chp && isspace (*chp))
 306     chp++;
 307   return chp;
 308 }
 309
 310 /* See documentation in common-utils.h.  */
 311
 312 const char *
 313 skip_to_space_const (const char *chp)
 314 {
 315   if (chp == NULL)
 316     return NULL;
 317   while (*chp && !isspace (*chp))
 318     chp++;
 319   return chp;
 320 }
 321
 322 /* See common/common-utils.h.  */
 323
 324 void
 325 free_vector_argv (std::vector<char *> &v)
 326 {
 327   for (char *el : v)
 328     xfree (el);
 329
 330   v.clear ();
 331 }
 332
 333 /* See common/common-utils.h.  */
 334
 335 std::string
 336 stringify_argv (const std::vector<char *> &args)
 337 {
 338   std::string ret;
 339
 340   if (!args.empty ())
 341     {
 342       for (auto s : args)
 343         if (s != NULL)
 344           {
 345             ret += s;
 346             ret += ' ';
 347           }
 348
 349       /* Erase the last whitespace.  */
 350       ret.erase (ret.end () - 1);
 351     }
 352
 353   return ret;
 354 }