1#ifndef HEADER_CURL_MEMORY_H
2#define HEADER_CURL_MEMORY_H
3/***************************************************************************
4 * _ _ ____ _
5 * Project ___| | | | _ \| |
6 * / __| | | | |_) | |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) 1998 - 2020, 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 ***************************************************************************/
24
25/*
26 * Nasty internal details ahead...
27 *
28 * File curl_memory.h must be included by _all_ *.c source files
29 * that use memory related functions strdup, malloc, calloc, realloc
30 * or free, and given source file is used to build libcurl library.
31 * It should be included immediately before memdebug.h as the last files
32 * included to avoid undesired interaction with other memory function
33 * headers in dependent libraries.
34 *
35 * There is nearly no exception to above rule. All libcurl source
36 * files in 'lib' subdirectory as well as those living deep inside
37 * 'packages' subdirectories and linked together in order to build
38 * libcurl library shall follow it.
39 *
40 * File lib/strdup.c is an exception, given that it provides a strdup
41 * clone implementation while using malloc. Extra care needed inside
42 * this one.
43 *
44 * The need for curl_memory.h inclusion is due to libcurl's feature
45 * of allowing library user to provide memory replacement functions,
46 * memory callbacks, at runtime with curl_global_init_mem()
47 *
48 * Any *.c source file used to build libcurl library that does not
49 * include curl_memory.h and uses any memory function of the five
50 * mentioned above will compile without any indication, but it will
51 * trigger weird memory related issues at runtime.
52 *
53 * OTOH some source files from 'lib' subdirectory may additionally be
54 * used directly as source code when using some curlx_ functions by
55 * third party programs that don't even use libcurl at all. When using
56 * these source files in this way it is necessary these are compiled
57 * with CURLX_NO_MEMORY_CALLBACKS defined, in order to ensure that no
58 * attempt of calling libcurl's memory callbacks is done from code
59 * which can not use this machinery.
60 *
61 * Notice that libcurl's 'memory tracking' system works chaining into
62 * the memory callback machinery. This implies that when compiling
63 * 'lib' source files with CURLX_NO_MEMORY_CALLBACKS defined this file
64 * disengages usage of libcurl's 'memory tracking' system, defining
65 * MEMDEBUG_NODEFINES and overriding CURLDEBUG purpose.
66 *
67 * CURLX_NO_MEMORY_CALLBACKS takes precedence over CURLDEBUG. This is
68 * done in order to allow building a 'memory tracking' enabled libcurl
69 * and at the same time allow building programs which do not use it.
70 *
71 * Programs and libraries in 'tests' subdirectories have specific
72 * purposes and needs, and as such each one will use whatever fits
73 * best, depending additionally whether it links with libcurl or not.
74 *
75 * Caveat emptor. Proper curlx_* separation is a work in progress
76 * the same as CURLX_NO_MEMORY_CALLBACKS usage, some adjustments may
77 * still be required. IOW don't use them yet, there are sharp edges.
78 */
79
80#ifdef HEADER_CURL_MEMDEBUG_H
81#error "Header memdebug.h shall not be included before curl_memory.h"
82#endif
83
84#ifndef CURLX_NO_MEMORY_CALLBACKS
85
86#ifndef CURL_DID_MEMORY_FUNC_TYPEDEFS /* only if not already done */
87/*
88 * The following memory function replacement typedef's are COPIED from
89 * curl/curl.h and MUST match the originals. We copy them to avoid having to
90 * include curl/curl.h here. We avoid that include since it includes stdio.h
91 * and other headers that may get messed up with defines done here.
92 */
93typedef void *(*curl_malloc_callback)(size_t size);
94typedef void (*curl_free_callback)(void *ptr);
95typedef void *(*curl_realloc_callback)(void *ptr, size_t size);
96typedef char *(*curl_strdup_callback)(const char *str);
97typedef void *(*curl_calloc_callback)(size_t nmemb, size_t size);
98#define CURL_DID_MEMORY_FUNC_TYPEDEFS
99#endif
100
101extern curl_malloc_callback Curl_cmalloc;
102extern curl_free_callback Curl_cfree;
103extern curl_realloc_callback Curl_crealloc;
104extern curl_strdup_callback Curl_cstrdup;
105extern curl_calloc_callback Curl_ccalloc;
106#if defined(WIN32) && defined(UNICODE)
107extern curl_wcsdup_callback Curl_cwcsdup;
108#endif
109
110#ifndef CURLDEBUG
111
112/*
113 * libcurl's 'memory tracking' system defines strdup, malloc, calloc,
114 * realloc and free, along with others, in memdebug.h in a different
115 * way although still using memory callbacks forward declared above.
116 * When using the 'memory tracking' system (CURLDEBUG defined) we do
117 * not define here the five memory functions given that definitions
118 * from memdebug.h are the ones that shall be used.
119 */
120
121#undef strdup
122#define strdup(ptr) Curl_cstrdup(ptr)
123#undef malloc
124#define malloc(size) Curl_cmalloc(size)
125#undef calloc
126#define calloc(nbelem,size) Curl_ccalloc(nbelem, size)
127#undef realloc
128#define realloc(ptr,size) Curl_crealloc(ptr, size)
129#undef free
130#define free(ptr) Curl_cfree(ptr)
131
132#ifdef WIN32
133# ifdef UNICODE
134# undef wcsdup
135# define wcsdup(ptr) Curl_cwcsdup(ptr)
136# undef _wcsdup
137# define _wcsdup(ptr) Curl_cwcsdup(ptr)
138# undef _tcsdup
139# define _tcsdup(ptr) Curl_cwcsdup(ptr)
140# else
141# undef _tcsdup
142# define _tcsdup(ptr) Curl_cstrdup(ptr)
143# endif
144#endif
145
146#endif /* CURLDEBUG */
147
148#else /* CURLX_NO_MEMORY_CALLBACKS */
149
150#ifndef MEMDEBUG_NODEFINES
151#define MEMDEBUG_NODEFINES
152#endif
153
154#endif /* CURLX_NO_MEMORY_CALLBACKS */
155
156#endif /* HEADER_CURL_MEMORY_H */
157