xmalloc.c

   1 /* **************************** */
   2 /* Memory management functions. */
   3 /* **************************** */
   4
   5 /* ***************************************************************** */
   6 /* Created by Kevin Locke (from numerous canonical examples).        */
   7 /*                                                                   */
   8 /* Adapted for use by smenu.                                         */
   9 /*                                                                   */
  10 /* I hereby place this file in the public domain.  It may be freely  */
  11 /* reproduced, distributed, used, modified, built upon, or otherwise */
  12 /* employed by anyone for any purpose without restriction.           */
  13 /* ***************************************************************** */
  14
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <errno.h>
  19
  20 #include "config.h"
  21 #include "xmalloc.h"
  22
  23 /* The following rpl_* function are necessary for AIX which doesn't     */
  24 /* provide 'GNU compatible' allocation functions.                       */
  25 /* Every call to malloc()/realloc() is then replaced by a call to       */
  26 /* rpl_malloc()/rpl_realloc() as defined in the GNU generated config.h. */
  27 /* """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" */
  28
  29 #ifdef malloc
  30
  31 #undef malloc
  32 extern void *malloc(size_t);
  33
  34 void *
  35 rpl_malloc(size_t size)
  36 {
  37   if (!size)
  38     size++;
  39   return malloc(size);
  40 }
  41
  42 #undef realloc
  43 extern void *
  44 realloc(void *, size_t);
  45
  46 void *
  47 rpl_realloc(void *ptr, size_t size)
  48 {
  49   if (!size)
  50     size++;
  51   return (ptr ? realloc(ptr, size) : malloc(size));
  52 }
  53
  54 #endif
  55
  56 /* ================================================================== */
  57 /* Customized malloc.                                                 */
  58 /* Displays an error message and exits gracefully if an error occurs. */
  59 /* ================================================================== */
  60 void *
  61 xmalloc(size_t size)
  62 {
  63   void  *allocated;
  64   size_t real_size;
  65
  66   real_size = (size > 0) ? size : 1;
  67   allocated = malloc(real_size);
  68   if (allocated == NULL)
  69   {
  70     fprintf(stderr,
  71             "Error: Insufficient memory (attempt to malloc %zu bytes)\n",
  72             size);
  73
  74     exit(EXIT_FAILURE);
  75   }
  76
  77   return allocated;
  78 }
  79
  80 /* ================================================================== */
  81 /* Customized calloc.                                                 */
  82 /* Displays an error message and exits gracefully if an error occurs. */
  83 /* ================================================================== */
  84 void *
  85 xcalloc(size_t n, size_t size)
  86 {
  87   void *allocated;
  88
  89   n         = (n > 0) ? n : 1;
  90   size      = (size > 0) ? size : 1;
  91   allocated = calloc(n, size);
  92   if (allocated == NULL)
  93   {
  94     fprintf(stderr,
  95             "Error: Insufficient memory (attempt to calloc %zu bytes)\n",
  96             size);
  97
  98     exit(EXIT_FAILURE);
  99   }
 100
 101   return allocated;
 102 }
 103
 104 /* ================================================================== */
 105 /* Customized realloc.                                                */
 106 /* Displays an error message and exits gracefully if an error occurs. */
 107 /* ================================================================== */
 108 void *
 109 xrealloc(void *p, size_t size)
 110 {
 111   void *allocated;
 112
 113   allocated = realloc(p, size);
 114   if (allocated == NULL && size > 0)
 115   {
 116     fprintf(stderr,
 117             "Error: Insufficient memory (attempt to realloc %zu bytes)\n",
 118             size);
 119
 120     exit(EXIT_FAILURE);
 121   }
 122
 123   return allocated;
 124 }
 125
 126 /* ================================================================== */
 127 /* strdup implementation using xmalloc.                               */
 128 /* Displays an error message and exits gracefully if an error occurs. */
 129 /* ================================================================== */
 130 char *
 131 xstrdup(const char *str)
 132 {
 133   char *p;
 134
 135   p = malloc(strlen(str) + 1);
 136
 137   if (p == NULL)
 138   {
 139     fprintf(stderr, "Error: Insufficient memory for xstrdup.\n");
 140     exit(EXIT_FAILURE);
 141   }
 142
 143   strcpy(p, str);
 144
 145   return p;
 146 }
 147
 148 /* ================================================================== */
 149 /* strndup implementation using xmalloc.                              */
 150 /* This version guarantees that there is a final '\0'.                */
 151 /* Displays an error message and exits gracefully if an error occurs. */
 152 /* ================================================================== */
 153 char *
 154 xstrndup(const char *str, size_t len)
 155 {
 156   char *p;
 157
 158   p = memchr(str, '\0', len);
 159
 160   if (p != NULL)
 161     len = p - str;
 162
 163   p = malloc(len + 1);
 164
 165   if (p == NULL)
 166   {
 167     fprintf(stderr, "Error: Insufficient memory for xstrndup.\n");
 168     exit(EXIT_FAILURE);
 169   }
 170
 171   memcpy(p, str, len);
 172   p[len] = '\0';
 173
 174   return p;
 175 }