mirror of
https://github.com/python/cpython.git
synced 2024-11-28 08:20:55 +01:00
b2336529ef
May or may not be related to bug 407680 (obmalloc.c - looks like it's corrupted). This repairs the illegal vrbl names, but leaves a pile of illegal macro names (_THIS_xxx, _SYSTEM_xxx, _SET_HOOKS, _FETCH_HOOKS).
744 lines
22 KiB
C
744 lines
22 KiB
C
/* An object allocator for Python.
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Here is an introduction to the layers of the Python memory architecture,
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showing where the object allocator is actually used (layer +2), It is
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called for every object allocation and deallocation (PyObject_New/Del),
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unless the object-specific allocators implement a proprietary allocation
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scheme (ex.: ints use a simple free list). This is also the place where
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the cyclic garbage collector operates selectively on container objects.
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Object-specific allocators
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_____ ______ ______ ________
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[ int ] [ dict ] [ list ] ... [ string ] Python core |
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+3 | <----- Object-specific memory -----> | <-- Non-object memory --> |
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_______________________________ | |
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[ Python's object allocator ] | |
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+2 | ####### Object memory ####### | <------ Internal buffers ------> |
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______________________________________________________________ |
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[ Python's raw memory allocator (PyMem_ API) ] |
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+1 | <----- Python memory (under PyMem manager's control) ------> | |
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__________________________________________________________________
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[ Underlying general-purpose allocator (ex: C library malloc) ]
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0 | <------ Virtual memory allocated for the python process -------> |
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=========================================================================
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_______________________________________________________________________
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[ OS-specific Virtual Memory Manager (VMM) ]
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-1 | <--- Kernel dynamic storage allocation & management (page-based) ---> |
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__________________________________ __________________________________
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[ ] [ ]
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-2 | <-- Physical memory: ROM/RAM --> | | <-- Secondary storage (swap) --> |
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*/
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/*==========================================================================*/
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/* A fast, special-purpose memory allocator for small blocks, to be used
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on top of a general-purpose malloc -- heavily based on previous art. */
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/* Vladimir Marangozov -- August 2000 */
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/*
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* "Memory management is where the rubber meets the road -- if we do the wrong
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* thing at any level, the results will not be good. And if we don't make the
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* levels work well together, we are in serious trouble." (1)
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*
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* (1) Paul R. Wilson, Mark S. Johnstone, Michael Neely, and David Boles,
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* "Dynamic Storage Allocation: A Survey and Critical Review",
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* in Proc. 1995 Int'l. Workshop on Memory Management, September 1995.
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*/
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/* #undef WITH_MEMORY_LIMITS */ /* disable mem limit checks */
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#define WITH_MALLOC_HOOKS /* for profiling & debugging */
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/*==========================================================================*/
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/*
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* Public functions exported by this allocator.
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*
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* -- Define and use these names in your code to obtain or release memory --
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*/
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#define _THIS_MALLOC PyCore_OBJECT_MALLOC_FUNC
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#define _THIS_CALLOC /* unused */
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#define _THIS_REALLOC PyCore_OBJECT_REALLOC_FUNC
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#define _THIS_FREE PyCore_OBJECT_FREE_FUNC
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/*
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* Underlying allocator's functions called by this allocator.
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* The underlying allocator is usually the one which comes with libc.
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*
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* -- Don't use these functions in your code (to avoid mixing allocators) --
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*
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* Redefine these __only__ if you are using a 3rd party general purpose
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* allocator which exports functions with names _other_ than the standard
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* malloc, calloc, realloc, free.
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*/
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#define _SYSTEM_MALLOC PyCore_MALLOC_FUNC
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#define _SYSTEM_CALLOC /* unused */
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#define _SYSTEM_REALLOC PyCore_REALLOC_FUNC
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#define _SYSTEM_FREE PyCore_FREE_FUNC
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/*
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* If malloc hooks are needed, names of the hooks' set & fetch
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* functions exported by this allocator.
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*/
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#ifdef WITH_MALLOC_HOOKS
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#define _SET_HOOKS _PyCore_ObjectMalloc_SetHooks
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#define _FETCH_HOOKS _PyCore_ObjectMalloc_FetchHooks
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#endif
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/*==========================================================================*/
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/*
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* Allocation strategy abstract:
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*
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* For small requests, the allocator sub-allocates <Big> blocks of memory.
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* Requests greater than 256 bytes are routed to the system's allocator.
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*
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* Small requests are grouped in size classes spaced 8 bytes apart, due
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* to the required valid alignment of the returned address. Requests of
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* a particular size are serviced from memory pools of 4K (one VMM page).
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* Pools are fragmented on demand and contain free lists of blocks of one
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* particular size class. In other words, there is a fixed-size allocator
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* for each size class. Free pools are shared by the different allocators
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* thus minimizing the space reserved for a particular size class.
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*
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* This allocation strategy is a variant of what is known as "simple
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* segregated storage based on array of free lists". The main drawback of
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* simple segregated storage is that we might end up with lot of reserved
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* memory for the different free lists, which degenerate in time. To avoid
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* this, we partition each free list in pools and we share dynamically the
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* reserved space between all free lists. This technique is quite efficient
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* for memory intensive programs which allocate mainly small-sized blocks.
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*
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* For small requests we have the following table:
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*
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* Request in bytes Size of allocated block Size class idx
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* ----------------------------------------------------------------
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* 1-8 8 0
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* 9-16 16 1
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* 17-24 24 2
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* 25-32 32 3
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* 33-40 40 4
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* 41-48 48 5
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* 49-56 56 6
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* 57-64 64 7
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* 65-72 72 8
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* ... ... ...
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* 241-248 248 30
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* 249-256 256 31
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*
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* 0, 257 and up: routed to the underlying allocator.
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*/
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/*==========================================================================*/
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/*
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* -- Main tunable settings section --
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*/
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/*
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* Alignment of addresses returned to the user. 8-bytes alignment works
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* on most current architectures (with 32-bit or 64-bit address busses).
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* The alignment value is also used for grouping small requests in size
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* classes spaced ALIGNMENT bytes apart.
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*
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* You shouldn't change this unless you know what you are doing.
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*/
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#define ALIGNMENT 8 /* must be 2^N */
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#define ALIGNMENT_SHIFT 3
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#define ALIGNMENT_MASK (ALIGNMENT - 1)
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/*
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* Max size threshold below which malloc requests are considered to be
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* small enough in order to use preallocated memory pools. You can tune
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* this value according to your application behaviour and memory needs.
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*
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* The following invariants must hold:
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* 1) ALIGNMENT <= SMALL_REQUEST_THRESHOLD <= 256
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* 2) SMALL_REQUEST_THRESHOLD == N * ALIGNMENT
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*
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* Although not required, for better performance and space efficiency,
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* it is recommended that SMALL_REQUEST_THRESHOLD is set to a power of 2.
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*/
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/*
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* For Python compiled on systems with 32 bit pointers and integers,
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* a value of 64 (= 8 * 8) is a reasonable speed/space tradeoff for
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* the object allocator. To adjust automatically this threshold for
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* systems with 64 bit pointers, we make this setting depend on a
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* Python-specific slot size unit = sizeof(long) + sizeof(void *),
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* which is expected to be 8, 12 or 16 bytes.
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*/
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#define _PYOBJECT_THRESHOLD ((SIZEOF_LONG + SIZEOF_VOID_P) * ALIGNMENT)
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#define SMALL_REQUEST_THRESHOLD _PYOBJECT_THRESHOLD /* must be N * ALIGNMENT */
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#define NB_SMALL_SIZE_CLASSES (SMALL_REQUEST_THRESHOLD / ALIGNMENT)
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/*
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* The system's VMM page size can be obtained on most unices with a
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* getpagesize() call or deduced from various header files. To make
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* things simpler, we assume that it is 4K, which is OK for most systems.
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* It is probably better if this is the native page size, but it doesn't
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* have to be.
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*/
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#define SYSTEM_PAGE_SIZE (4 * 1024)
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#define SYSTEM_PAGE_SIZE_MASK (SYSTEM_PAGE_SIZE - 1)
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/*
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* Maximum amount of memory managed by the allocator for small requests.
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*/
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#ifdef WITH_MEMORY_LIMITS
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#ifndef SMALL_MEMORY_LIMIT
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#define SMALL_MEMORY_LIMIT (64 * 1024 * 1024) /* 64 MB -- more? */
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#endif
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#endif
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/*
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* The allocator sub-allocates <Big> blocks of memory (called arenas) aligned
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* on a page boundary. This is a reserved virtual address space for the
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* current process (obtained through a malloc call). In no way this means
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* that the memory arenas will be used entirely. A malloc(<Big>) is usually
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* an address range reservation for <Big> bytes, unless all pages within this
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* space are referenced subsequently. So malloc'ing big blocks and not using
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* them does not mean "wasting memory". It's an addressable range wastage...
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*
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* Therefore, allocating arenas with malloc is not optimal, because there is
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* some address space wastage, but this is the most portable way to request
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* memory from the system accross various platforms.
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*/
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#define ARENA_SIZE (256 * 1024 - SYSTEM_PAGE_SIZE) /* 256k - 1p */
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#ifdef WITH_MEMORY_LIMITS
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#define MAX_ARENAS (SMALL_MEMORY_LIMIT / ARENA_SIZE)
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#endif
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/*
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* Size of the pools used for small blocks. Should be a power of 2,
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* between 1K and SYSTEM_PAGE_SIZE, that is: 1k, 2k, 4k, eventually 8k.
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*/
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#define POOL_SIZE SYSTEM_PAGE_SIZE /* must be 2^N */
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#define POOL_SIZE_MASK SYSTEM_PAGE_SIZE_MASK
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#define POOL_MAGIC 0x74D3A651 /* authentication id */
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#define ARENA_NB_POOLS (ARENA_SIZE / POOL_SIZE)
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#define ARENA_NB_PAGES (ARENA_SIZE / SYSTEM_PAGE_SIZE)
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/*
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* -- End of tunable settings section --
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*/
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/*==========================================================================*/
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/*
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* Locking
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*
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* To reduce lock contention, it would probably be better to refine the
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* crude function locking with per size class locking. I'm not positive
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* however, whether it's worth switching to such locking policy because
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* of the performance penalty it might introduce.
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*
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* The following macros describe the simplest (should also be the fastest)
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* lock object on a particular platform and the init/fini/lock/unlock
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* operations on it. The locks defined here are not expected to be recursive
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* because it is assumed that they will always be called in the order:
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* INIT, [LOCK, UNLOCK]*, FINI.
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*/
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/*
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* Python's threads are serialized, so object malloc locking is disabled.
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*/
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#define SIMPLELOCK_DECL(lock) /* simple lock declaration */
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#define SIMPLELOCK_INIT(lock) /* allocate (if needed) and initialize */
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#define SIMPLELOCK_FINI(lock) /* free/destroy an existing lock */
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#define SIMPLELOCK_LOCK(lock) /* acquire released lock */
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#define SIMPLELOCK_UNLOCK(lock) /* release acquired lock */
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/*
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* Basic types
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* I don't care if these are defined in <sys/types.h> or elsewhere. Axiom.
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*/
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#undef uchar
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#define uchar unsigned char /* assuming == 8 bits */
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#undef ushort
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#define ushort unsigned short /* assuming >= 16 bits */
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#undef uint
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#define uint unsigned int /* assuming >= 16 bits */
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#undef ulong
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#define ulong unsigned long /* assuming >= 32 bits */
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#undef off_t
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#define off_t uint /* 16 bits <= off_t <= 64 bits */
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/* When you say memory, my mind reasons in terms of (pointers to) blocks */
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typedef uchar block;
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/* Pool for small blocks */
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struct pool_header {
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union { block *_padding;
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uint count; } ref; /* number of allocated blocks */
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block *freeblock; /* pool's free list head */
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struct pool_header *nextpool; /* next pool of this size class */
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struct pool_header *prevpool; /* previous pool "" */
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struct pool_header *pooladdr; /* pool address (always aligned) */
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uint magic; /* pool magic number */
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uint szidx; /* block size class index */
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uint capacity; /* pool capacity in # of blocks */
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};
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typedef struct pool_header *poolp;
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#undef ROUNDUP
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#define ROUNDUP(x) (((x) + ALIGNMENT_MASK) & ~ALIGNMENT_MASK)
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#define POOL_OVERHEAD ROUNDUP(sizeof(struct pool_header))
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#define DUMMY_SIZE_IDX 0xffff /* size class of newly cached pools */
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/*==========================================================================*/
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/*
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* This malloc lock
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*/
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SIMPLELOCK_DECL(_malloc_lock);
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#define LOCK() SIMPLELOCK_LOCK(_malloc_lock)
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#define UNLOCK() SIMPLELOCK_UNLOCK(_malloc_lock)
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#define LOCK_INIT() SIMPLELOCK_INIT(_malloc_lock)
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#define LOCK_FINI() SIMPLELOCK_FINI(_malloc_lock)
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/*
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* Pool table -- doubly linked lists of partially used pools
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*/
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#define PTA(x) ((poolp )((uchar *)&(usedpools[2*(x)]) - 2*sizeof(block *)))
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#define PT(x) PTA(x), PTA(x)
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static poolp usedpools[2 * ((NB_SMALL_SIZE_CLASSES + 7) / 8) * 8] = {
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PT(0), PT(1), PT(2), PT(3), PT(4), PT(5), PT(6), PT(7)
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#if NB_SMALL_SIZE_CLASSES > 8
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, PT(8), PT(9), PT(10), PT(11), PT(12), PT(13), PT(14), PT(15)
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#if NB_SMALL_SIZE_CLASSES > 16
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, PT(16), PT(17), PT(18), PT(19), PT(20), PT(21), PT(22), PT(23)
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#if NB_SMALL_SIZE_CLASSES > 24
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, PT(24), PT(25), PT(26), PT(27), PT(28), PT(29), PT(30), PT(31)
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#if NB_SMALL_SIZE_CLASSES > 32
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, PT(32), PT(33), PT(34), PT(35), PT(36), PT(37), PT(38), PT(39)
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#if NB_SMALL_SIZE_CLASSES > 40
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, PT(40), PT(41), PT(42), PT(43), PT(44), PT(45), PT(46), PT(47)
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#if NB_SMALL_SIZE_CLASSES > 48
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, PT(48), PT(49), PT(50), PT(51), PT(52), PT(53), PT(54), PT(55)
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#if NB_SMALL_SIZE_CLASSES > 56
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, PT(56), PT(57), PT(58), PT(59), PT(60), PT(61), PT(62), PT(63)
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#endif /* NB_SMALL_SIZE_CLASSES > 56 */
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#endif /* NB_SMALL_SIZE_CLASSES > 48 */
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#endif /* NB_SMALL_SIZE_CLASSES > 40 */
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#endif /* NB_SMALL_SIZE_CLASSES > 32 */
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#endif /* NB_SMALL_SIZE_CLASSES > 24 */
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#endif /* NB_SMALL_SIZE_CLASSES > 16 */
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#endif /* NB_SMALL_SIZE_CLASSES > 8 */
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};
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/*
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* Free (cached) pools
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*/
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static poolp freepools = NULL; /* free list for cached pools */
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/*
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* Arenas
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*/
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static uint arenacnt = 0; /* number of allocated arenas */
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static uint watermark = ARENA_NB_POOLS; /* number of pools allocated from
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the current arena */
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static block *arenalist = NULL; /* list of allocated arenas */
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static block *arenabase = NULL; /* free space start address in
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current arena */
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/*
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* Hooks
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*/
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#ifdef WITH_MALLOC_HOOKS
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static void *(*malloc_hook)(size_t) = NULL;
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static void *(*calloc_hook)(size_t, size_t) = NULL;
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static void *(*realloc_hook)(void *, size_t) = NULL;
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static void (*free_hook)(void *) = NULL;
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#endif /* !WITH_MALLOC_HOOKS */
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/*==========================================================================*/
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/* malloc */
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/*
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* The basic blocks are ordered by decreasing execution frequency,
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* which minimizes the number of jumps in the most common cases,
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* improves branching prediction and instruction scheduling (small
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* block allocations typically result in a couple of instructions).
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* Unless the optimizer reorders everything, being too smart...
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*/
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void *
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_THIS_MALLOC(size_t nbytes)
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{
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block *bp;
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poolp pool;
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poolp next;
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uint size;
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#ifdef WITH_MALLOC_HOOKS
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if (malloc_hook != NULL)
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return (*malloc_hook)(nbytes);
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#endif
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/*
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* This implicitly redirects malloc(0)
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*/
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if ((nbytes - 1) < SMALL_REQUEST_THRESHOLD) {
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LOCK();
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/*
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* Most frequent paths first
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*/
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size = (uint )(nbytes - 1) >> ALIGNMENT_SHIFT;
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pool = usedpools[size + size];
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if (pool != pool->nextpool) {
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/*
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* There is a used pool for this size class.
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* Pick up the head block of its free list.
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*/
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++pool->ref.count;
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bp = pool->freeblock;
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if ((pool->freeblock = *(block **)bp) != NULL) {
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UNLOCK();
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return (void *)bp;
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}
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/*
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* Reached the end of the free list, try to extend it
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*/
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if (pool->ref.count < pool->capacity) {
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/*
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* There is room for another block
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*/
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size++;
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size <<= ALIGNMENT_SHIFT; /* block size */
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pool->freeblock = (block *)pool + \
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POOL_OVERHEAD + \
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pool->ref.count * size;
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*(block **)(pool->freeblock) = NULL;
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UNLOCK();
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return (void *)bp;
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}
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/*
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* Pool is full, unlink from used pools
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*/
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next = pool->nextpool;
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pool = pool->prevpool;
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next->prevpool = pool;
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pool->nextpool = next;
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UNLOCK();
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return (void *)bp;
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}
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/*
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* Try to get a cached free pool
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*/
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pool = freepools;
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if (pool != NULL) {
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/*
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* Unlink from cached pools
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*/
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freepools = pool->nextpool;
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init_pool:
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/*
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* Frontlink to used pools
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*/
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next = usedpools[size + size]; /* == prev */
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pool->nextpool = next;
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pool->prevpool = next;
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next->nextpool = pool;
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next->prevpool = pool;
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pool->ref.count = 1;
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if (pool->szidx == size) {
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/*
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* Luckily, this pool last contained blocks
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* of the same size class, so its header
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* and free list are already initialized.
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*/
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bp = pool->freeblock;
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pool->freeblock = *(block **)bp;
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UNLOCK();
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return (void *)bp;
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}
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/*
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* Initialize the pool header and free list
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* then return the first block.
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*/
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pool->szidx = size;
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size++;
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size <<= ALIGNMENT_SHIFT; /* block size */
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bp = (block *)pool + POOL_OVERHEAD;
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pool->freeblock = bp + size;
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*(block **)(pool->freeblock) = NULL;
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pool->capacity = (POOL_SIZE - POOL_OVERHEAD) / size;
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UNLOCK();
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return (void *)bp;
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}
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/*
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* Allocate new pool
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*/
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if (watermark < ARENA_NB_POOLS) {
|
|
/* commit malloc(POOL_SIZE) from the current arena */
|
|
commit_pool:
|
|
watermark++;
|
|
pool = (poolp )arenabase;
|
|
arenabase += POOL_SIZE;
|
|
pool->pooladdr = pool;
|
|
pool->magic = (uint )POOL_MAGIC;
|
|
pool->szidx = DUMMY_SIZE_IDX;
|
|
goto init_pool;
|
|
}
|
|
/*
|
|
* Allocate new arena
|
|
*/
|
|
#ifdef WITH_MEMORY_LIMITS
|
|
if (!(arenacnt < MAX_ARENAS)) {
|
|
UNLOCK();
|
|
goto redirect;
|
|
}
|
|
#endif
|
|
/*
|
|
* With malloc, we can't avoid loosing one page address space
|
|
* per arena due to the required alignment on page boundaries.
|
|
*/
|
|
bp = (block *)_SYSTEM_MALLOC(ARENA_SIZE + SYSTEM_PAGE_SIZE);
|
|
if (bp == NULL) {
|
|
UNLOCK();
|
|
goto redirect;
|
|
}
|
|
/*
|
|
* Keep a reference in the list of allocated arenas. We might
|
|
* want to release (some of) them in the future. The first
|
|
* word is never used, no matter whether the returned address
|
|
* is page-aligned or not, so we safely store a pointer in it.
|
|
*/
|
|
*(block **)bp = arenalist;
|
|
arenalist = bp;
|
|
arenacnt++;
|
|
watermark = 0;
|
|
/* Page-round up */
|
|
arenabase = bp + (SYSTEM_PAGE_SIZE -
|
|
((off_t )bp & SYSTEM_PAGE_SIZE_MASK));
|
|
goto commit_pool;
|
|
}
|
|
|
|
/* The small block allocator ends here. */
|
|
|
|
redirect:
|
|
|
|
/*
|
|
* Redirect the original request to the underlying (libc) allocator.
|
|
* We jump here on bigger requests, on error in the code above (as a
|
|
* last chance to serve the request) or when the max memory limit
|
|
* has been reached.
|
|
*/
|
|
return (void *)_SYSTEM_MALLOC(nbytes);
|
|
}
|
|
|
|
/* free */
|
|
|
|
void
|
|
_THIS_FREE(void *p)
|
|
{
|
|
poolp pool;
|
|
poolp next, prev;
|
|
uint size;
|
|
off_t offset;
|
|
|
|
#ifdef WITH_MALLOC_HOOKS
|
|
if (free_hook != NULL) {
|
|
(*free_hook)(p);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
if (p == NULL) /* free(NULL) has no effect */
|
|
return;
|
|
|
|
offset = (off_t )p & POOL_SIZE_MASK;
|
|
pool = (poolp )((block *)p - offset);
|
|
if (pool->pooladdr != pool || pool->magic != (uint )POOL_MAGIC) {
|
|
_SYSTEM_FREE(p);
|
|
return;
|
|
}
|
|
|
|
LOCK();
|
|
/*
|
|
* At this point, the pool is not empty
|
|
*/
|
|
if ((*(block **)p = pool->freeblock) == NULL) {
|
|
/*
|
|
* Pool was full
|
|
*/
|
|
pool->freeblock = (block *)p;
|
|
--pool->ref.count;
|
|
/*
|
|
* Frontlink to used pools
|
|
* This mimics LRU pool usage for new allocations and
|
|
* targets optimal filling when several pools contain
|
|
* blocks of the same size class.
|
|
*/
|
|
size = pool->szidx;
|
|
next = usedpools[size + size];
|
|
prev = next->prevpool;
|
|
pool->nextpool = next;
|
|
pool->prevpool = prev;
|
|
next->prevpool = pool;
|
|
prev->nextpool = pool;
|
|
UNLOCK();
|
|
return;
|
|
}
|
|
/*
|
|
* Pool was not full
|
|
*/
|
|
pool->freeblock = (block *)p;
|
|
if (--pool->ref.count != 0) {
|
|
UNLOCK();
|
|
return;
|
|
}
|
|
/*
|
|
* Pool is now empty, unlink from used pools
|
|
*/
|
|
next = pool->nextpool;
|
|
prev = pool->prevpool;
|
|
next->prevpool = prev;
|
|
prev->nextpool = next;
|
|
/*
|
|
* Frontlink to free pools
|
|
* This ensures that previously freed pools will be allocated
|
|
* later (being not referenced, they are perhaps paged out).
|
|
*/
|
|
pool->nextpool = freepools;
|
|
freepools = pool;
|
|
UNLOCK();
|
|
return;
|
|
}
|
|
|
|
/* realloc */
|
|
|
|
void *
|
|
_THIS_REALLOC(void *p, size_t nbytes)
|
|
{
|
|
block *bp;
|
|
poolp pool;
|
|
uint size;
|
|
|
|
#ifdef WITH_MALLOC_HOOKS
|
|
if (realloc_hook != NULL)
|
|
return (*realloc_hook)(p, nbytes);
|
|
#endif
|
|
|
|
if (p == NULL)
|
|
return _THIS_MALLOC(nbytes);
|
|
|
|
/* realloc(p, 0) on big blocks is redirected. */
|
|
pool = (poolp )((block *)p - ((off_t )p & POOL_SIZE_MASK));
|
|
if (pool->pooladdr != pool || pool->magic != (uint )POOL_MAGIC) {
|
|
/* We haven't allocated this block */
|
|
if (!(nbytes > SMALL_REQUEST_THRESHOLD) && nbytes) {
|
|
/* small request */
|
|
size = nbytes;
|
|
goto malloc_copy_free;
|
|
}
|
|
bp = (block *)_SYSTEM_REALLOC(p, nbytes);
|
|
}
|
|
else {
|
|
/* We're in charge of this block */
|
|
size = (pool->szidx + 1) << ALIGNMENT_SHIFT; /* block size */
|
|
if (size >= nbytes) {
|
|
/* Don't bother if a smaller size was requested
|
|
except for realloc(p, 0) == free(p), ret NULL */
|
|
if (nbytes == 0) {
|
|
_THIS_FREE(p);
|
|
bp = NULL;
|
|
}
|
|
else
|
|
bp = (block *)p;
|
|
}
|
|
else {
|
|
|
|
malloc_copy_free:
|
|
|
|
bp = (block *)_THIS_MALLOC(nbytes);
|
|
if (bp != NULL) {
|
|
memcpy(bp, p, size);
|
|
_THIS_FREE(p);
|
|
}
|
|
}
|
|
}
|
|
return (void *)bp;
|
|
}
|
|
|
|
/* calloc */
|
|
|
|
/* -- unused --
|
|
void *
|
|
_THIS_CALLOC(size_t nbel, size_t elsz)
|
|
{
|
|
void *p;
|
|
size_t nbytes;
|
|
|
|
#ifdef WITH_MALLOC_HOOKS
|
|
if (calloc_hook != NULL)
|
|
return (*calloc_hook)(nbel, elsz);
|
|
#endif
|
|
|
|
nbytes = nbel * elsz;
|
|
p = _THIS_MALLOC(nbytes);
|
|
if (p != NULL)
|
|
memset(p, 0, nbytes);
|
|
return p;
|
|
}
|
|
*/
|
|
|
|
/*==========================================================================*/
|
|
|
|
/*
|
|
* Hooks
|
|
*/
|
|
|
|
#ifdef WITH_MALLOC_HOOKS
|
|
|
|
void
|
|
_SET_HOOKS( void *(*malloc_func)(size_t),
|
|
void *(*calloc_func)(size_t, size_t),
|
|
void *(*realloc_func)(void *, size_t),
|
|
void (*free_func)(void *) )
|
|
{
|
|
LOCK();
|
|
malloc_hook = malloc_func;
|
|
calloc_hook = calloc_func;
|
|
realloc_hook = realloc_func;
|
|
free_hook = free_func;
|
|
UNLOCK();
|
|
}
|
|
|
|
void
|
|
_FETCH_HOOKS( void *(**malloc_funcp)(size_t),
|
|
void *(**calloc_funcp)(size_t, size_t),
|
|
void *(**realloc_funcp)(void *, size_t),
|
|
void (**free_funcp)(void *) )
|
|
{
|
|
LOCK();
|
|
*malloc_funcp = malloc_hook;
|
|
*calloc_funcp = calloc_hook;
|
|
*realloc_funcp = realloc_hook;
|
|
*free_funcp = free_hook;
|
|
UNLOCK();
|
|
}
|
|
#endif /* !WITH_MALLOC_HOOKS */
|