1 /* xmalloc.c -- malloc with out of memory checking 2 3 Copyright (C) 1990-2000, 2002-2006, 2008-2012 Free Software Foundation, Inc. 4 5 This program is free software: you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 17 18 #include <config.h> 19 20 #if ! HAVE_INLINE 21 # define static_inline 22 #endif 23 #include "xalloc.h" 24 #undef static_inline 25 26 #include <stdlib.h> 27 #include <string.h> 28 29 /* 1 if calloc is known to be compatible with GNU calloc. This 30 matters if we are not also using the calloc module, which defines 31 HAVE_CALLOC_GNU and supports the GNU API even on non-GNU platforms. */ 32 #if defined HAVE_CALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__) 33 enum { HAVE_GNU_CALLOC = 1 }; 34 #else 35 enum { HAVE_GNU_CALLOC = 0 }; 36 #endif 37 38 /* Allocate N bytes of memory dynamically, with error checking. */ 39 40 void * 41 xmalloc (size_t n) 42 { 43 void *p = malloc (n); 44 if (!p && n != 0) 45 xalloc_die (); 46 return p; 47 } 48 49 /* Change the size of an allocated block of memory P to N bytes, 50 with error checking. */ 51 52 void * 53 xrealloc (void *p, size_t n) 54 { 55 if (!n && p) 56 { 57 /* The GNU and C99 realloc behaviors disagree here. Act like 58 GNU, even if the underlying realloc is C99. */ 59 free (p); 60 return NULL; 61 } 62 63 p = realloc (p, n); 64 if (!p && n) 65 xalloc_die (); 66 return p; 67 } 68 69 /* If P is null, allocate a block of at least *PN bytes; otherwise, 70 reallocate P so that it contains more than *PN bytes. *PN must be 71 nonzero unless P is null. Set *PN to the new block's size, and 72 return the pointer to the new block. *PN is never set to zero, and 73 the returned pointer is never null. */ 74 75 void * 76 x2realloc (void *p, size_t *pn) 77 { 78 return x2nrealloc (p, pn, 1); 79 } 80 81 /* Allocate S bytes of zeroed memory dynamically, with error checking. 82 There's no need for xnzalloc (N, S), since it would be equivalent 83 to xcalloc (N, S). */ 84 85 void * 86 xzalloc (size_t s) 87 { 88 return memset (xmalloc (s), 0, s); 89 } 90 91 /* Allocate zeroed memory for N elements of S bytes, with error 92 checking. S must be nonzero. */ 93 94 void * 95 xcalloc (size_t n, size_t s) 96 { 97 void *p; 98 /* Test for overflow, since some calloc implementations don't have 99 proper overflow checks. But omit overflow and size-zero tests if 100 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never 101 returns NULL if successful. */ 102 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s)) 103 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0))) 104 xalloc_die (); 105 return p; 106 } 107 108 /* Clone an object P of size S, with error checking. There's no need 109 for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any 110 need for an arithmetic overflow check. */ 111 112 void * 113 xmemdup (void const *p, size_t s) 114 { 115 return memcpy (xmalloc (s), p, s); 116 } 117 118 /* Clone STRING. */ 119 120 char * 121 xstrdup (char const *string) 122 { 123 return xmemdup (string, strlen (string) + 1); 124 } 125