diff options
| -rw-r--r-- | lib/curl_memory.h | 82 | ||||
| -rw-r--r-- | lib/easy.c | 8 |
2 files changed, 86 insertions, 4 deletions
diff --git a/lib/curl_memory.h b/lib/curl_memory.h index e11945823..c1e92513f 100644 --- a/lib/curl_memory.h +++ b/lib/curl_memory.h @@ -7,7 +7,7 @@ * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * - * Copyright (C) 1998 - 2009, Daniel Stenberg, <daniel@haxx.se>, et al. + * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms @@ -22,7 +22,65 @@ * ***************************************************************************/ -#include <curl/curl.h> /* for the typedefs */ +/* + * Nasty internal details ahead... + * + * File curl_memory.h must be included by _all_ *.c source files + * that use memory related functions strdup, malloc, calloc, realloc + * or free, and given source file is used to build libcurl library. + * + * There is nearly no exception to above rule. All libcurl source + * files in 'lib' subdirectory as well as those living deep inside + * 'packages' subdirectories and linked together in order to build + * libcurl library shall follow it. + * + * File lib/strdup.c is an exception, given that it provides a strdup + * clone implementation while using malloc. Extra care needed inside + * this one. TODO: revisit this paragraph and related code. + * + * The need for curl_memory.h inclusion is due to libcurl's feature + * of allowing library user to provide memory replacement functions, + * memory callbacks, at runtime with curl_global_init_mem() + * + * Any *.c source file used to build libcurl library that does not + * include curl_memory.h and uses any memory function of the five + * mentioned above will compile without any indication, but it will + * trigger weird memory related issues at runtime. + * + * OTOH some source files from 'lib' subdirectory may additionally be + * used directly as source code when using some curlx_ functions by + * third party programs that don't even use libcurl at all. When using + * these source files in this way it is necessary these are compiled + * with CURLX_NO_MEMORY_CALLBACKS defined, in order to ensure that no + * attempt of calling libcurl's memory callbacks is done from code + * which can not use this machinery. + * + * Notice that libcurl's 'memory tracking' system works chaining into + * the memory callback machinery. This implies that when compiling + * 'lib' source files with CURLX_NO_MEMORY_CALLBACKS defined this file + * disengages usage of libcurl's 'memory tracking' system, defining + * MEMDEBUG_NODEFINES and overriding CURLDEBUG purpose. + * + * CURLX_NO_MEMORY_CALLBACKS takes precedence over CURLDEBUG. This is + * done in order to allow building a 'memory tracking' enabled libcurl + * and at the same time allow building programs which do not use it. + * + * Programs and libraries in 'tests' subdirectories have specific + * purposes and needs, and as such each one will use whatever fits + * best, depending additionally wether it links with libcurl or not. + * + * Caveat emptor. Proper curlx_* separation is a work in progress + * the same as CURLX_NO_MEMORY_CALLBACKS usage, some adjustments may + * still be required. IOW don't use them yet, there are sharp edges. + */ + +#ifdef HEADER_CURL_MEMDEBUG_H +#error "Header memdebug.h shall not be included before curl_memory.h" +#endif + +#ifndef CURLX_NO_MEMORY_CALLBACKS + +#include <curl/curl.h> /* for the callback typedefs */ extern curl_malloc_callback Curl_cmalloc; extern curl_free_callback Curl_cfree; @@ -31,8 +89,16 @@ extern curl_strdup_callback Curl_cstrdup; extern curl_calloc_callback Curl_ccalloc; #ifndef CURLDEBUG -/* Only do this define-mania if we're not using the memdebug system, as that - has preference on this magic. */ + +/* + * libcurl's 'memory tracking' system defines strdup, malloc, calloc, + * realloc and free, along with others, in memdebug.h in a different + * way although still using memory callbacks forward declared above. + * When using the 'memory tracking' system (CURLDEBUG defined) we do + * not define here the five memory functions given that definitions + * from memdebug.h are the ones that shall be used. + */ + #undef strdup #define strdup(ptr) Curl_cstrdup(ptr) #undef malloc @@ -44,6 +110,14 @@ extern curl_calloc_callback Curl_ccalloc; #undef free #define free(ptr) Curl_cfree(ptr) +#endif /* CURLDEBUG */ + +#else /* CURLX_NO_MEMORY_CALLBACKS */ + +#ifndef MEMDEBUG_NODEFINES +#define MEMDEBUG_NODEFINES #endif +#endif /* CURLX_NO_MEMORY_CALLBACKS */ + #endif /* HEADER_CURL_MEMORY_H */ diff --git a/lib/easy.c b/lib/easy.c index 2739598ef..dc95a6d44 100644 --- a/lib/easy.c +++ b/lib/easy.c @@ -22,6 +22,14 @@ #include "curl_setup.h" +/* + * See comment in curl_memory.h for the explanation of this sanity check. + */ + +#ifdef CURLX_NO_MEMORY_CALLBACKS +#error "libcurl shall not ever be built with CURLX_NO_MEMORY_CALLBACKS defined" +#endif + #ifdef HAVE_NETINET_IN_H #include <netinet/in.h> #endif |