1 #ifndef HEADER_CURL_MEMORY_H 2 #define HEADER_CURL_MEMORY_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 11 * 12 * This software is licensed as described in the file COPYING, which 13 * you should have received as part of this distribution. The terms 14 * are also available at https://curl.se/docs/copyright.html. 15 * 16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 17 * copies of the Software, and permit persons to whom the Software is 18 * furnished to do so, under the terms of the COPYING file. 19 * 20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 21 * KIND, either express or implied. 22 * 23 * SPDX-License-Identifier: curl 24 * 25 ***************************************************************************/ 26 27 /* 28 * Nasty internal details ahead... 29 * 30 * File curl_memory.h must be included by _all_ *.c source files 31 * that use memory related functions strdup, malloc, calloc, realloc 32 * or free, and given source file is used to build libcurl library. 33 * It should be included immediately before memdebug.h as the last files 34 * included to avoid undesired interaction with other memory function 35 * headers in dependent libraries. 36 * 37 * There is nearly no exception to above rule. All libcurl source 38 * files in 'lib' subdirectory as well as those living deep inside 39 * 'packages' subdirectories and linked together in order to build 40 * libcurl library shall follow it. 41 * 42 * File lib/strdup.c is an exception, given that it provides a strdup 43 * clone implementation while using malloc. Extra care needed inside 44 * this one. 45 * 46 * The need for curl_memory.h inclusion is due to libcurl's feature 47 * of allowing library user to provide memory replacement functions, 48 * memory callbacks, at runtime with curl_global_init_mem() 49 * 50 * Any *.c source file used to build libcurl library that does not 51 * include curl_memory.h and uses any memory function of the five 52 * mentioned above will compile without any indication, but it will 53 * trigger weird memory related issues at runtime. 54 * 55 * OTOH some source files from 'lib' subdirectory may additionally be 56 * used directly as source code when using some curlx_ functions by 57 * third party programs that don't even use libcurl at all. When using 58 * these source files in this way it is necessary these are compiled 59 * with CURLX_NO_MEMORY_CALLBACKS defined, in order to ensure that no 60 * attempt of calling libcurl's memory callbacks is done from code 61 * which can not use this machinery. 62 * 63 * Notice that libcurl's 'memory tracking' system works chaining into 64 * the memory callback machinery. This implies that when compiling 65 * 'lib' source files with CURLX_NO_MEMORY_CALLBACKS defined this file 66 * disengages usage of libcurl's 'memory tracking' system, defining 67 * MEMDEBUG_NODEFINES and overriding CURLDEBUG purpose. 68 * 69 * CURLX_NO_MEMORY_CALLBACKS takes precedence over CURLDEBUG. This is 70 * done in order to allow building a 'memory tracking' enabled libcurl 71 * and at the same time allow building programs which do not use it. 72 * 73 * Programs and libraries in 'tests' subdirectories have specific 74 * purposes and needs, and as such each one will use whatever fits 75 * best, depending additionally whether it links with libcurl or not. 76 * 77 * Caveat emptor. Proper curlx_* separation is a work in progress 78 * the same as CURLX_NO_MEMORY_CALLBACKS usage, some adjustments may 79 * still be required. IOW don't use them yet, there are sharp edges. 80 */ 81 82 #ifdef HEADER_CURL_MEMDEBUG_H 83 #error "Header memdebug.h shall not be included before curl_memory.h" 84 #endif 85 86 #ifndef CURLX_NO_MEMORY_CALLBACKS 87 88 #ifndef CURL_DID_MEMORY_FUNC_TYPEDEFS /* only if not already done */ 89 /* 90 * The following memory function replacement typedef's are COPIED from 91 * curl/curl.h and MUST match the originals. We copy them to avoid having to 92 * include curl/curl.h here. We avoid that include since it includes stdio.h 93 * and other headers that may get messed up with defines done here. 94 */ 95 typedef void *(*curl_malloc_callback)(size_t size); 96 typedef void (*curl_free_callback)(void *ptr); 97 typedef void *(*curl_realloc_callback)(void *ptr, size_t size); 98 typedef char *(*curl_strdup_callback)(const char *str); 99 typedef void *(*curl_calloc_callback)(size_t nmemb, size_t size); 100 #define CURL_DID_MEMORY_FUNC_TYPEDEFS 101 #endif 102 103 extern curl_malloc_callback Curl_cmalloc; 104 extern curl_free_callback Curl_cfree; 105 extern curl_realloc_callback Curl_crealloc; 106 extern curl_strdup_callback Curl_cstrdup; 107 extern curl_calloc_callback Curl_ccalloc; 108 #if defined(WIN32) && defined(UNICODE) 109 extern curl_wcsdup_callback Curl_cwcsdup; 110 #endif 111 112 #ifndef CURLDEBUG 113 114 /* 115 * libcurl's 'memory tracking' system defines strdup, malloc, calloc, 116 * realloc and free, along with others, in memdebug.h in a different 117 * way although still using memory callbacks forward declared above. 118 * When using the 'memory tracking' system (CURLDEBUG defined) we do 119 * not define here the five memory functions given that definitions 120 * from memdebug.h are the ones that shall be used. 121 */ 122 123 #undef strdup 124 #define strdup(ptr) Curl_cstrdup(ptr) 125 #undef malloc 126 #define malloc(size) Curl_cmalloc(size) 127 #undef calloc 128 #define calloc(nbelem,size) Curl_ccalloc(nbelem, size) 129 #undef realloc 130 #define realloc(ptr,size) Curl_crealloc(ptr, size) 131 #undef free 132 #define free(ptr) Curl_cfree(ptr) 133 134 #ifdef WIN32 135 # ifdef UNICODE 136 # undef wcsdup 137 # define wcsdup(ptr) Curl_cwcsdup(ptr) 138 # undef _wcsdup 139 # define _wcsdup(ptr) Curl_cwcsdup(ptr) 140 # undef _tcsdup 141 # define _tcsdup(ptr) Curl_cwcsdup(ptr) 142 # else 143 # undef _tcsdup 144 # define _tcsdup(ptr) Curl_cstrdup(ptr) 145 # endif 146 #endif 147 148 #endif /* CURLDEBUG */ 149 150 #else /* CURLX_NO_MEMORY_CALLBACKS */ 151 152 #ifndef MEMDEBUG_NODEFINES 153 #define MEMDEBUG_NODEFINES 154 #endif 155 156 #endif /* CURLX_NO_MEMORY_CALLBACKS */ 157 158 #endif /* HEADER_CURL_MEMORY_H */ 159