lib/xmalloc.c

   1 /* xmalloc.c -- malloc with out of memory checking
   2    Copyright (C) 1990, 91, 92, 93, 94, 95, 96 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 #if HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #if __STDC__
  23 # define VOID void
  24 #else
  25 # define VOID char
  26 #endif
  27
  28 #include <sys/types.h>
  29
  30 #if STDC_HEADERS
  31 # include <stdlib.h>
  32 #else
  33 VOID *calloc ();
  34 VOID *malloc ();
  35 VOID *realloc ();
  36 void free ();
  37 #endif
  38
  39 #if ENABLE_NLS
  40 # include <libintl.h>
  41 # define _(Text) gettext (Text)
  42 #else
  43 # define textdomain(Domain)
  44 # define _(Text) Text
  45 #endif
  46
  47 #include "error.h"
  48
  49 #ifndef EXIT_FAILURE
  50 # define EXIT_FAILURE 1
  51 #endif
  52
  53 /* Prototypes for functions defined here.  */
  54 #if defined (__STDC__) && __STDC__
  55 static VOID *fixup_null_alloc (size_t n);
  56 VOID *xmalloc (size_t n);
  57 VOID *xcalloc (size_t n, size_t s);
  58 VOID *xrealloc (VOID *p, size_t n);
  59 #endif
  60
  61
  62 /* Exit value when the requested amount of memory is not available.
  63    The caller may set it to some other value.  */
  64 int xmalloc_exit_failure = EXIT_FAILURE;
  65
  66 #if __STDC__ && (HAVE_VPRINTF || HAVE_DOPRNT)
  67 void error (int, int, const char *, ...);
  68 #else
  69 void error ();
  70 #endif
  71
  72 static VOID *
  73 fixup_null_alloc (n)
  74      size_t n;
  75 {
  76   VOID *p;
  77
  78   p = 0;
  79   if (n == 0)
  80     p = malloc ((size_t) 1);
  81   if (p == 0)
  82     error (xmalloc_exit_failure, 0, _("Memory exhausted"));
  83   return p;
  84 }
  85
  86 /* Allocate N bytes of memory dynamically, with error checking.  */
  87
  88 VOID *
  89 xmalloc (n)
  90      size_t n;
  91 {
  92   VOID *p;
  93
  94   p = malloc (n);
  95   if (p == 0)
  96     p = fixup_null_alloc (n);
  97   return p;
  98 }
  99
 100 /* Allocate memory for N elements of S bytes, with error checking.  */
 101
 102 VOID *
 103 xcalloc (n, s)
 104      size_t n, s;
 105 {
 106   VOID *p;
 107
 108   p = calloc (n, s);
 109   if (p == 0)
 110     p = fixup_null_alloc (n);
 111   return p;
 112 }
 113
 114 /* Change the size of an allocated block of memory P to N bytes,
 115    with error checking.
 116    If P is NULL, run xmalloc.  */
 117
 118 VOID *
 119 xrealloc (p, n)
 120      VOID *p;
 121      size_t n;
 122 {
 123   if (p == 0)
 124     return xmalloc (n);
 125   p = realloc (p, n);
 126   if (p == 0)
 127     p = fixup_null_alloc (n);
 128   return p;
 129 }