| 1 | /* realloc() function that is glibc compatible. |
| 2 | |
| 3 | Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2020 Free Software |
| 4 | Foundation, Inc. |
| 5 | |
| 6 | This program is free software: you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 3 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | /* written by Jim Meyering and Bruno Haible */ |
| 20 | |
| 21 | #define _GL_USE_STDLIB_ALLOC 1 |
| 22 | #include <config.h> |
| 23 | |
| 24 | /* Only the AC_FUNC_REALLOC macro defines 'realloc' already in config.h. */ |
| 25 | #ifdef realloc |
| 26 | # define NEED_REALLOC_GNU 1 |
| 27 | /* Whereas the gnulib module 'realloc-gnu' defines HAVE_REALLOC_GNU. */ |
| 28 | #elif GNULIB_REALLOC_GNU && !HAVE_REALLOC_GNU |
| 29 | # define NEED_REALLOC_GNU 1 |
| 30 | #endif |
| 31 | |
| 32 | /* Infer the properties of the system's malloc function. |
| 33 | The gnulib module 'malloc-gnu' defines HAVE_MALLOC_GNU. */ |
| 34 | #if GNULIB_MALLOC_GNU && HAVE_MALLOC_GNU |
| 35 | # define SYSTEM_MALLOC_GLIBC_COMPATIBLE 1 |
| 36 | #endif |
| 37 | |
| 38 | #include <stdlib.h> |
| 39 | |
| 40 | #include <errno.h> |
| 41 | |
| 42 | /* Change the size of an allocated block of memory P to N bytes, |
| 43 | with error checking. If N is zero, change it to 1. If P is NULL, |
| 44 | use malloc. */ |
| 45 | |
| 46 | void * |
| 47 | rpl_realloc (void *p, size_t n) |
| 48 | { |
| 49 | void *result; |
| 50 | |
| 51 | #if NEED_REALLOC_GNU |
| 52 | if (n == 0) |
| 53 | { |
| 54 | n = 1; |
| 55 | |
| 56 | /* In theory realloc might fail, so don't rely on it to free. */ |
| 57 | free (p); |
| 58 | p = NULL; |
| 59 | } |
| 60 | #endif |
| 61 | |
| 62 | if (p == NULL) |
| 63 | { |
| 64 | #if GNULIB_REALLOC_GNU && !NEED_REALLOC_GNU && !SYSTEM_MALLOC_GLIBC_COMPATIBLE |
| 65 | if (n == 0) |
| 66 | n = 1; |
| 67 | #endif |
| 68 | result = malloc (n); |
| 69 | } |
| 70 | else |
| 71 | result = realloc (p, n); |
| 72 | |
| 73 | #if !HAVE_REALLOC_POSIX |
| 74 | if (result == NULL) |
| 75 | errno = ENOMEM; |
| 76 | #endif |
| 77 | |
| 78 | return result; |
| 79 | } |