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 #define XALLOC_INLINE _GL_EXTERN_INLINE 21 22 #include "xalloc.h" 23 24 #include <stdlib.h> 25 #include <string.h> 26 27 /* 1 if calloc is known to be compatible with GNU calloc. This 28 matters if we are not also using the calloc module, which defines 29 HAVE_CALLOC_GNU and supports the GNU API even on non-GNU platforms. */ 30 #if defined HAVE_CALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__) 31 enum { HAVE_GNU_CALLOC = 1 }; 32 #else 33 enum { HAVE_GNU_CALLOC = 0 }; 34 #endif 35 36 /* Allocate N bytes of memory dynamically, with error checking. */ 37 38 void * 39 xmalloc (size_t n) 40 { 41 void *p = malloc (n); 42 if (!p && n != 0) 43 xalloc_die (); 44 return p; 45 } 46 47 /* Change the size of an allocated block of memory P to N bytes, 48 with error checking. */ 49 50 void * 51 xrealloc (void *p, size_t n) 52 { 53 if (!n && p) 54 { 55 /* The GNU and C99 realloc behaviors disagree here. Act like 56 GNU, even if the underlying realloc is C99. */ 57 free (p); 58 return NULL; 59 } 60 61 p = realloc (p, n); 62 if (!p && n) 63 xalloc_die (); 64 return p; 65 } 66 67 /* If P is null, allocate a block of at least *PN bytes; otherwise, 68 reallocate P so that it contains more than *PN bytes. *PN must be 69 nonzero unless P is null. Set *PN to the new block's size, and 70 return the pointer to the new block. *PN is never set to zero, and 71 the returned pointer is never null. */ 72 73 void * 74 x2realloc (void *p, size_t *pn) 75 { 76 return x2nrealloc (p, pn, 1); 77 } 78 79 /* Allocate S bytes of zeroed memory dynamically, with error checking. 80 There's no need for xnzalloc (N, S), since it would be equivalent 81 to xcalloc (N, S). */ 82 83 void * 84 xzalloc (size_t s) 85 { 86 return memset (xmalloc (s), 0, s); 87 } 88 89 /* Allocate zeroed memory for N elements of S bytes, with error 90 checking. S must be nonzero. */ 91 92 void * 93 xcalloc (size_t n, size_t s) 94 { 95 void *p; 96 /* Test for overflow, since some calloc implementations don't have 97 proper overflow checks. But omit overflow and size-zero tests if 98 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never 99 returns NULL if successful. */ 100 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s)) 101 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0))) 102 xalloc_die (); 103 return p; 104 } 105 106 /* Clone an object P of size S, with error checking. There's no need 107 for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any 108 need for an arithmetic overflow check. */ 109 110 void * 111 xmemdup (void const *p, size_t s) 112 { 113 return memcpy (xmalloc (s), p, s); 114 } 115 116 /* Clone STRING. */ 117 118 char * 119 xstrdup (char const *string) 120 { 121 return xmemdup (string, strlen (string) + 1); 122 } 123
