gdb/common/common-utils.c

   1 /* Shared general utility routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2019 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 void *
  26 xzalloc (size_t size)
  27 {
  28   return xcalloc (1, size);
  29 }
  30
  31 /* Like asprintf/vasprintf but get an internal_error if the call
  32    fails. */
  33
  34 char *
  35 xstrprintf (const char *format, ...)
  36 {
  37   char *ret;
  38   va_list args;
  39
  40   va_start (args, format);
  41   ret = xstrvprintf (format, args);
  42   va_end (args);
  43   return ret;
  44 }
  45
  46 char *
  47 xstrvprintf (const char *format, va_list ap)
  48 {
  49   char *ret = NULL;
  50   int status = vasprintf (&ret, format, ap);
  51
  52   /* NULL is returned when there was a memory allocation problem, or
  53      any other error (for instance, a bad format string).  A negative
  54      status (the printed length) with a non-NULL buffer should never
  55      happen, but just to be sure.  */
  56   if (ret == NULL || status < 0)
  57     internal_error (__FILE__, __LINE__, _("vasprintf call failed"));
  58   return ret;
  59 }
  60
  61 int
  62 xsnprintf (char *str, size_t size, const char *format, ...)
  63 {
  64   va_list args;
  65   int ret;
  66
  67   va_start (args, format);
  68   ret = vsnprintf (str, size, format, args);
  69   gdb_assert (ret < size);
  70   va_end (args);
  71
  72   return ret;
  73 }
  74
  75 /* See documentation in common-utils.h.  */
  76
  77 std::string
  78 string_printf (const char* fmt, ...)
  79 {
  80   va_list vp;
  81   int size;
  82
  83   va_start (vp, fmt);
  84   size = vsnprintf (NULL, 0, fmt, vp);
  85   va_end (vp);
  86
  87   std::string str (size, '\0');
  88
  89   /* C++11 and later guarantee std::string uses contiguous memory and
  90      always includes the terminating '\0'.  */
  91   va_start (vp, fmt);
  92   vsprintf (&str[0], fmt, vp);
  93   va_end (vp);
  94
  95   return str;
  96 }
  97
  98 /* See documentation in common-utils.h.  */
  99
 100 std::string
 101 string_vprintf (const char* fmt, va_list args)
 102 {
 103   va_list vp;
 104   size_t size;
 105
 106   va_copy (vp, args);
 107   size = vsnprintf (NULL, 0, fmt, vp);
 108   va_end (vp);
 109
 110   std::string str (size, '\0');
 111
 112   /* C++11 and later guarantee std::string uses contiguous memory and
 113      always includes the terminating '\0'.  */
 114   vsprintf (&str[0], fmt, args);
 115
 116   return str;
 117 }
 118
 119
 120 /* See documentation in common-utils.h.  */
 121
 122 void
 123 string_appendf (std::string &str, const char *fmt, ...)
 124 {
 125   va_list vp;
 126
 127   va_start (vp, fmt);
 128   string_vappendf (str, fmt, vp);
 129   va_end (vp);
 130 }
 131
 132
 133 /* See documentation in common-utils.h.  */
 134
 135 void
 136 string_vappendf (std::string &str, const char *fmt, va_list args)
 137 {
 138   va_list vp;
 139   int grow_size;
 140
 141   va_copy (vp, args);
 142   grow_size = vsnprintf (NULL, 0, fmt, vp);
 143   va_end (vp);
 144
 145   size_t curr_size = str.size ();
 146   str.resize (curr_size + grow_size);
 147
 148   /* C++11 and later guarantee std::string uses contiguous memory and
 149      always includes the terminating '\0'.  */
 150   vsprintf (&str[curr_size], fmt, args);
 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 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 char *chp)
 290 {
 291   if (chp == NULL)
 292     return NULL;
 293   while (*chp && !isspace (*chp))
 294     chp++;
 295   return chp;
 296 }
 297
 298 /* See documentation in common-utils.h.  */
 299
 300 char *
 301 skip_to_space (char *chp)
 302 {
 303   return (char *) skip_to_space ((const char *) chp);
 304 }
 305
 306 /* See common/common-utils.h.  */
 307
 308 void
 309 free_vector_argv (std::vector<char *> &v)
 310 {
 311   for (char *el : v)
 312     xfree (el);
 313
 314   v.clear ();
 315 }
 316
 317 /* See common/common-utils.h.  */
 318
 319 std::string
 320 stringify_argv (const std::vector<char *> &args)
 321 {
 322   std::string ret;
 323
 324   if (!args.empty () && args[0] != NULL)
 325     {
 326       for (auto s : args)
 327         if (s != NULL)
 328           {
 329             ret += s;
 330             ret += ' ';
 331           }
 332
 333       /* Erase the last whitespace.  */
 334       ret.erase (ret.end () - 1);
 335     }
 336
 337   return ret;
 338 }
 339
 340 /* See common/common-utils.h.  */
 341
 342 ULONGEST
 343 align_up (ULONGEST v, int n)
 344 {
 345   /* Check that N is really a power of two.  */
 346   gdb_assert (n && (n & (n-1)) == 0);
 347   return (v + n - 1) & -n;
 348 }
 349
 350 /* See common/common-utils.h.  */
 351
 352 ULONGEST
 353 align_down (ULONGEST v, int n)
 354 {
 355   /* Check that N is really a power of two.  */
 356   gdb_assert (n && (n & (n-1)) == 0);
 357   return (v & -n);
 358 }