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 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this file,

  * You can obtain one at http://mozilla.org/MPL/2.0/. */

 #ifndef mozmemory_wrap_h

 #define mozmemory_wrap_h

 /*

  * This header contains #defines which tweak the names of various memory

  * allocation functions.

  *

  * There are several types of functions related to memory allocation

  * that are meant to be used publicly by the Gecko codebase:

  *

  * - malloc implementation functions:

  *   - malloc

  *   - posix_memalign

  *   - aligned_alloc

  *   - calloc

  *   - realloc

  *   - free

  *   - memalign

  *   - valloc

  *   - malloc_usable_size

  *   - malloc_good_size

  *   Some of these functions are specific to some systems, but for

  *   convenience, they are treated as being cross-platform, and available

  *   as such.

  *

  * - duplication functions:

  *   - strndup

  *   - strdup

  *   - wcsdup (Windows only)

  *

  * - jemalloc specific functions:

  *   - jemalloc_stats

  *   - jemalloc_purge_freed_pages

  *   - jemalloc_free_dirty_pages

  *   (these functions are native to mozjemalloc, and have compatibility

  *   implementations for jemalloc3)

  *

  * These functions are all exported as part of libmozglue (see

  * $(topsrcdir)/mozglue/build/Makefile.in), with a few implementation

  * peculiarities:

  *

  * - On Windows, the malloc implementation functions are all prefixed with

  *   "je_", the duplication functions are prefixed with "wrap_", and jemalloc

  *   specific functions are left unprefixed. All these functions are however

  *   aliased when exporting them, such that the resulting mozglue.dll exports

  *   them unprefixed (see $(topsrcdir)/mozglue/build/mozglue.def.in). The

  *   prefixed malloc implementation and duplication functions are not

  *   exported.

  *

  * - On MacOSX, the system libc has a zone allocator, which allows us to

  *   hook custom malloc implementation functions without exporting them.

  *   The malloc implementation functions are all prefixed with "je_" and used

  *   this way from the custom zone allocator. They are not exported.

  *   Duplication functions are not included, since they will call the custom

  *   zone allocator anyways. Jemalloc-specific functions are also left

  *   unprefixed.

  *

  * - On Android, both malloc implementation and duplication functions are

  *   prefixed with "__wrap_". Additionally, C++ allocation functions

  *   (operator new/delete) are also exported and prefixed with "__wrap_".

  *   Jemalloc specific functions are left unprefixed.

  *

  * - On Gonk, all functions are left unprefixed. Additionally, C++ allocation

  *   functions (operator new/delete) are also exported and unprefixed.

  *

  * - On other systems (mostly Linux), all functions are left unprefixed.

  *

  * Only Android and Gonk add C++ allocation functions.

  *

  * Proper exporting of the various functions is done with the MOZ_MEMORY_API

  * and MOZ_JEMALLOC_API macros. MOZ_MEMORY_API is meant to be used for malloc

  * implementation and duplication functions, while MOZ_JEMALLOC_API is

  * dedicated to jemalloc specific functions.

  *

  *

  * All these functions are meant to be called with no prefix from Gecko code.

  * In most cases, this is because that's how they are available at runtime.

  * However, on Android, "__wrap_" prefixing is left to the build-time linker

  * (with -Wl,--wrap), or to the mozmemory.h header for malloc_good_size and

  * jemalloc specific functions.

  *

  *

  * Within libmozglue (when MOZ_MEMORY_IMPL is defined), all the functions

  * should be suffixed with "_impl" both for declarations and use.

  * That is, the implementation declaration for e.g. strdup would look like:

  *   char* strdup_impl(const char *)

  * That implementation would call malloc by using "malloc_impl".

  *

  * While mozjemalloc uses these "_impl" suffixed helpers, jemalloc3, being

  * third-party code, doesn't, but instead has an elaborate way to mangle

  * individual functions. See under "Run jemalloc configure script" in

  * $(topsrcdir)/configure.in.

  *

  *

  * When building with replace-malloc support, the above still holds, but

  * the malloc implementation and jemalloc specific functions are the

  * replace-malloc functions from replace_malloc.c.

  *

  * The actual jemalloc/mozjemalloc implementation is prefixed with "je_".

  *

  * Thus, when MOZ_REPLACE_MALLOC is defined, the "_impl" suffixed macros

  * expand to "je_" prefixed function when building mozjemalloc or

  * jemalloc3/mozjemalloc_compat, where MOZ_JEMALLOC_IMPL is defined.

  *

  * In other cases, the "_impl" suffixed macros follow the original scheme,

  * except on Windows and MacOSX, where they would expand to "je_" prefixed

  * functions. Instead, they are left unmodified (malloc_impl expands to

  * malloc_impl).

  */

 #ifndef MOZ_MEMORY

 #  error Should only include mozmemory_wrap.h when MOZ_MEMORY is set.

 #endif

 #if defined(MOZ_JEMALLOC_IMPL) && !defined(MOZ_MEMORY_IMPL)

 #  define MOZ_MEMORY_IMPL

 #endif

 #if defined(MOZ_MEMORY_IMPL) && !defined(IMPL_MFBT)

 #  ifdef MFBT_API /* mozilla/Types.h was already included */

 #    error mozmemory_wrap.h has to be included before mozilla/Types.h when MOZ_MEMORY_IMPL is set and IMPL_MFBT is not.

 #  endif

 #  define IMPL_MFBT

 #endif

 #include "mozilla/Types.h"

 #if !defined(MOZ_NATIVE_JEMALLOC)

 #  ifdef MOZ_MEMORY_IMPL

 #    if defined(MOZ_JEMALLOC_IMPL) && defined(MOZ_REPLACE_MALLOC)

 #      define mozmem_malloc_impl(a)     je_ ## a

 #      define mozmem_jemalloc_impl(a)   je_ ## a

 #    else

 #      define MOZ_JEMALLOC_API MFBT_API

 #      ifdef MOZ_REPLACE_JEMALLOC

 #        define MOZ_MEMORY_API MFBT_API

 #        define mozmem_malloc_impl(a)     replace_ ## a

 #        define mozmem_jemalloc_impl(a)   replace_ ## a

 #      elif (defined(XP_WIN) || defined(XP_DARWIN))

 #        if defined(MOZ_REPLACE_MALLOC)

 #          define mozmem_malloc_impl(a)   a ## _impl

 #        else

 #          define mozmem_malloc_impl(a)   je_ ## a

 #        endif

 #      else

 #        define MOZ_MEMORY_API MFBT_API

 #        if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)

 #          define MOZ_WRAP_NEW_DELETE

 #        endif

 #      endif

 #    endif

 #    ifdef XP_WIN

 #      define mozmem_dup_impl(a)      wrap_ ## a

 #    endif

 #  endif

 #  if defined(MOZ_WIDGET_ANDROID)

 #    ifndef mozmem_malloc_impl

 #      define mozmem_malloc_impl(a)   __wrap_ ## a

 #    endif

 #    define mozmem_dup_impl(a)      __wrap_ ## a

 #  endif

 /* All other jemalloc3 functions are prefixed with "je_", except when

  * building against an unprefixed system jemalloc library */

 #  define je_(a) je_ ## a

 #else /* defined(MOZ_NATIVE_JEMALLOC) */

 #  define je_(a) a

 #endif

 #if !defined(MOZ_MEMORY_IMPL) || defined(MOZ_NATIVE_JEMALLOC)

 #  define MOZ_MEMORY_API MFBT_API

 #  define MOZ_JEMALLOC_API MFBT_API

 #endif

 #ifndef MOZ_MEMORY_API

 #  define MOZ_MEMORY_API

 #endif

 #ifndef MOZ_JEMALLOC_API

 #  define MOZ_JEMALLOC_API

 #endif

 #ifndef mozmem_malloc_impl

 #  define mozmem_malloc_impl(a)   a

 #endif

 #ifndef mozmem_dup_impl

 #  define mozmem_dup_impl(a)      a

 #endif

 #ifndef mozmem_jemalloc_impl

 #  define mozmem_jemalloc_impl(a) a

 #endif

 /* Malloc implementation functions */

 #define malloc_impl              mozmem_malloc_impl(malloc)

 #define posix_memalign_impl      mozmem_malloc_impl(posix_memalign)

 #define aligned_alloc_impl       mozmem_malloc_impl(aligned_alloc)

 #define calloc_impl              mozmem_malloc_impl(calloc)

 #define realloc_impl             mozmem_malloc_impl(realloc)

 #define free_impl                mozmem_malloc_impl(free)

 #define memalign_impl            mozmem_malloc_impl(memalign)

 #define valloc_impl              mozmem_malloc_impl(valloc)

 #define malloc_usable_size_impl  mozmem_malloc_impl(malloc_usable_size)

 #define malloc_good_size_impl    mozmem_malloc_impl(malloc_good_size)

 /* Duplication functions */

 #define strndup_impl   mozmem_dup_impl(strndup)

 #define strdup_impl    mozmem_dup_impl(strdup)

 #ifdef XP_WIN

 #  define wcsdup_impl  mozmem_dup_impl(wcsdup)

 #endif

 /* String functions */

 #ifdef ANDROID

 /* Bug 801571 and Bug 879668, libstagefright uses vasprintf, causing malloc()/

  * free() to be mismatched between bionic and mozglue implementation.

  */

 #define vasprintf_impl  mozmem_dup_impl(vasprintf)

 #define asprintf_impl   mozmem_dup_impl(asprintf)

 #endif

 /* Jemalloc specific function */

 #define jemalloc_stats_impl              mozmem_jemalloc_impl(jemalloc_stats)

 #define jemalloc_purge_freed_pages_impl  mozmem_jemalloc_impl(jemalloc_purge_freed_pages)

 #define jemalloc_free_dirty_pages_impl   mozmem_jemalloc_impl(jemalloc_free_dirty_pages)

 #endif /* mozmemory_wrap_h */