git.m6w6.name Git - awesomized/libmemcached/blob - docs/source/libmemcached/memcached_memory_allocators.rst

   1 ========================================
   2 Use custom allocators for embedded usage
   3 ========================================
   4
   5 .. index:: object: memcached_st
   6
   7 Manage memory allocator functions
   8
   9 --------
  10 SYNOPSIS
  11 --------
  12
  13 #include <libmemcached/memcached.h>
  14
  15 .. function:: memcached_return_t memcached_set_memory_allocators (memcached_st *ptr, memcached_malloc_fn mem_malloc, memcached_free_fn mem_free, memcached_realloc_fn mem_realloc, memcached_calloc_fn mem_calloc, void *context)
  16
  17 .. function:: void memcached_get_memory_allocators (memcached_st *ptr, memcached_malloc_fn *mem_malloc, memcached_free_fn *mem_free, memcached_realloc_fn *mem_realloc, memcached_calloc_fn *mem_calloc)
  18
  19 .. function:: void * memcached_get_memory_allocators_context(const memcached_st *ptr)
  20
  21 .. function:: void * (*memcached_malloc_fn) (memcached_st *ptr, const size_t size, void *context)
  22
  23 .. function:: void * (*memcached_realloc_fn) (memcached_st *ptr, void *mem, const size_t size, void *context)
  24
  25 .. function:: void (*memcached_free_fn) (memcached_st *ptr, void *mem, void *context)
  26
  27 .. function:: void * (*memcached_calloc_fn) (memcached_st *ptr, size_t nelem, const size_t elsize, void *context)
  28
  29 Compile and link with -lmemcached
  30
  31 -----------
  32 DESCRIPTION
  33 -----------
  34
  35 libmemcached(3) allows you to specify your own memory allocators, optimized
  36 for your application. This enables libmemcached to be used inside of applications that have their own malloc implementation.
  37
  38 :func:`memcached_set_memory_allocators` is used to set the memory
  39 allocators used by the memcached instance specified by ptr. Please note that
  40 you cannot override only one of the memory allocators, you have to specify a
  41 complete new set if you want to override one of them. All of the memory
  42 allocation functions should behave as specified in the C99 standard. Specify
  43 NULL as all functions to reset them to the default values.
  44
  45 :func:`memcached_get_memory_allocators` is used to get the currently used
  46 memory allocators by a memcached handle.
  47
  48 :func:`memcached_get_memory_allocators_context` returns the void \* that
  49 was passed in during the call to :func:`memcached_set_memory_allocators`.
  50
  51 The first argument to the memory allocator functions is a pointer to a
  52 memcached structure, the is passed as const and you will need to clone
  53 it in order to make use of any operation which would modify it.
  54
  55 -----
  56 NOTES
  57 -----
  58
  59 In version 0.38 all functions were modified to have a context void pointer
  60 passed to them. This was so that customer allocators could have their
  61 own space for memory.
  62
  63 ------
  64 RETURN
  65 ------
  66
  67 :func:`memcached_set_memory_allocators` return `MEMCACHED_SUCCESS`
  68 upon success, and `MEMCACHED_FAILURE` if you don't pass a complete set
  69 of function pointers.
  70
  71 --------
  72 SEE ALSO
  73 --------
  74
  75 .. only:: man
  76
  77   :manpage:`memcached(1)` :manpage:`libmemcached(3)` :manpage:`memcached_strerror(3)`