git.m6w6.name Git - m6w6/libmemcached/blob - docs/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
  14 #include <libmemcached/memcached.h>
  15
  16 .. c: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);
  17
  18 .. c: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);
  19
  20 .. c:function:: void * memcached_get_memory_allocators_context(const memcached_st *ptr);
  21
  22 .. c:function:: void * (*memcached_malloc_fn) (memcached_st *ptr, const size_t size, void *context);
  23
  24 .. c:function:: void * (*memcached_realloc_fn) (memcached_st *ptr, void *mem, const size_t size, void *context);
  25
  26 .. c:function:: void (*memcached_free_fn) (memcached_st *ptr, void *mem, void *context);
  27
  28 .. c:function:: void * (*memcached_calloc_fn) (memcached_st *ptr, size_t nelem, const size_t elsize, void *context);
  29
  30 Compile and link with -lmemcached
  31
  32
  33
  34 -----------
  35 DESCRIPTION
  36 -----------
  37
  38
  39 libmemcached(3) allows you to specify your own memory allocators, optimized
  40 for your application. This enables libmemcached to be used inside of applications that have their own malloc implementation.
  41
  42 :c:func:`memcached_set_memory_allocators()` is used to set the memory
  43 allocators used by the memcached instance specified by ptr. Please note that
  44 you cannot override only one of the memory allocators, you have to specify a
  45 complete new set if you want to override one of them. All of the memory
  46 allocation functions should behave as specified in the C99 standard. Specify
  47 NULL as all functions to reset them to the default values.
  48
  49 :c:func:`memcached_get_memory_allocators()` is used to get the currently used
  50 memory allocators by a mamcached handle.
  51
  52 :c:func:`memcached_get_memory_allocators_context()` returns the void \* that
  53 was passed in during the call to :c:func:`memcached_set_memory_allocators()`.
  54
  55 The first argument to the memory allocator functions is a pointer to a
  56 memcached structure, the is passed as const and you will need to clone
  57 it in order to make use of any operation which would modify it.
  58
  59
  60 -----
  61 NOTES
  62 -----
  63
  64
  65 In version 0.38 all functions were modified to have a context void pointer
  66 passed to them. This was so that customer allocators could have their
  67 own space for memory.
  68
  69
  70 ------
  71 RETURN
  72 ------
  73
  74
  75 :c:func:`memcached_set_memory_allocators()` return :c:type:`MEMCACHED_SUCCESS`
  76 upon success, and :c:type:`MEMCACHED_FAILURE` if you don't pass a complete set
  77 of function pointers.
  78
  79
  80 ----
  81 HOME
  82 ----
  83
  84
  85 To find out more information please check:
  86 `http://libmemcached.org/ <http://libmemcached.org/>`_
  87
  88
  89 --------
  90 SEE ALSO
  91 --------
  92
  93 :manpage:`memcached(1)` :manpage:`libmemcached(3)` :manpage:`memcached_strerror(3)`