#include <sicstus/sicstus.h> typedef int SP_InitAllocHook(size_t alignment, void *cookie); typedef void SP_DeinitAllocHook(void *cookie); typedef void * SP_AllocHook(size_t size, size_t *actual_sizep, void *cookie); typedef int SP_FreeHook(void *ptr, size_t size, int force, void *cookie); int SP_set_memalloc_hooks(int hint, SP_InitAllocHook *init_alloc_hook, SP_DeinitAllocHook *deinit_alloc_hook, SP_AllocHook *alloc_hook, SP_FreeHook *free_hook, void *cookie);
Defines the Prolog memory manager's bottom layer.
Must be called before
malloc()et al. will be used for all allocations. This is useful, e.g. in combination with tools like valgrind.
In this case all the other arguments must be
When this option is used some memory statistics, e.g.
statistics/[0,2], may be unavailable or misleading.
On some systems,
SP_SET_MEMALLOC_HOOKS_HINT_USE_MALLOC will be
used automatically when the SICStus runtime detects that it is being
run within valgrind (http://www.valgrind.org/). This
behavior can be disabled by explicitly setting the system property (or environment
(see System Properties and Environment Variables). This feature is
currently (4.0.8) available on x86 and x86_64 Linux.
Please note: SICStus can only use
platforms where it is guaranteed to return sufficiently aligned memory
2 * sizeof(void*)). This is true at least on Linux, Mac OS X
and Windows (on Windows
_aligned_malloc() is used instead of
malloc()). On platforms where alignment cannot be ensured
SICStus will not be able to allocate memory and initialization will
SP_SET_MEMALLOC_HOOKS_HINT_USE_MALLOC is used.
Please note: When
SP_SET_MEMALLOC_HOOKS_HINT_USE_MALLOC is used
SP_deinitialize() may not be able to reclaim all memory. This
is mainly a problem when SICstus is embedded into some other
application that continues to run after calling
SP_deinitialize(). This limitations also means that leak
detecton tools like valgrind will report large amounts of
alignmentis guaranteed to be a power of 2, and is used by
latest_end(exclusive) are the bounds within which address-constrained memory blocks must fit. Both are aligned according to
alignmentand non-zero. The function can do whatever initialization that this layer of memory management wants to do. It should return non-zero if it succeeds, zero if the memory manager bottom layer could not be initialized, in which case initialization of the SICStus runtime will fail.
SP_deinitialize()when the Prolog engine shuts down. The function can do any necessary cleaning up.
sizebytes aligned at a multiple of
alignment. The actual size of the piece of memory should be returned in
*actual_sizep. Should return
NULLif it cannot allocate a suitable piece of memory. Note that the memory returned need not be aligned as long as there is room for an aligned block of at least
free_hookmust accept the piece of memory; otherwise, it only accepts it if it is able to return it to the operating system.
free_hookshould return non-zero iff it accepts the piece of memory. Otherwise, the upper layer will keep using the memory as if it were not freed.
SP_set_memalloc_hooks()is passed to each hook function. One possible use is to keep track of multiple SICStus runtimes within the same process.
Non-zero on success, Zero on error, e.g. if called after
The default bottom layers look at the system properties PROLOGINITSIZE, PROLOGINCSIZE, PROLOGKEEPSIZE and PROLOGMAXSIZE. They are useful for customizing the default memory manager. If you redefine the bottom layer, you can choose to ignore these system properties.
Initializing the Prolog Engine. System Properties and Environment Variables.