Internal Memory Allocation

Overview

// typedefs

typedef struct apr_allocator_t apr_allocator_t;
typedef struct apr_memnode_t apr_memnode_t;

// structs

struct apr_memnode_t;

// global functions

apr_status_t
apr_allocator_create(apr_allocator_t** allocator);

void
apr_allocator_destroy(apr_allocator_t* allocator);

apr_memnode_t*
apr_allocator_alloc(
    apr_allocator_t* allocator,
    apr_size_t size
);

void
apr_allocator_free(
    apr_allocator_t* allocator,
    apr_memnode_t* memnode
);

void
apr_allocator_owner_set(
    apr_allocator_t* allocator,
    apr_pool_t* pool
);

apr_pool_t*
apr_allocator_owner_get(apr_allocator_t* allocator);

void
apr_allocator_max_free_set(
    apr_allocator_t* allocator,
    apr_size_t size
);

void
apr_allocator_mutex_set(
    apr_allocator_t* allocator,
    apr_thread_mutex_t* mutex
);

apr_thread_mutex_t*
apr_allocator_mutex_get(apr_allocator_t* allocator);

// macros

#define APR_ALLOCATOR_MAX_FREE_UNLIMITED
#define APR_MEMNODE_T_SIZE

Detailed Documentation

Typedefs

typedef struct apr_allocator_t apr_allocator_t

the allocator structure

typedef struct apr_memnode_t apr_memnode_t

the structure which holds information about the allocation

Global Functions

apr_status_t
apr_allocator_create(apr_allocator_t** allocator)

Create a new allocator

Parameters:

allocator

The allocator we have just created.

void
apr_allocator_destroy(apr_allocator_t* allocator)

Destroy an allocator Any memnodes not given back to the allocator prior to destroying will not be free()d.

Parameters:

allocator

The allocator to be destroyed

apr_memnode_t*
apr_allocator_alloc(
    apr_allocator_t* allocator,
    apr_size_t size
)

Allocate a block of mem from the allocator

Parameters:

allocator	The allocator to allocate from
size	The size of the mem to allocate (excluding the memnode structure)

void
apr_allocator_free(
    apr_allocator_t* allocator,
    apr_memnode_t* memnode
)

Free a list of blocks of mem, giving them back to the allocator. The list is typically terminated by a memnode with its next field set to NULL.

Parameters:

allocator	The allocator to give the mem back to
memnode	The memory node to return

void
apr_allocator_owner_set(
    apr_allocator_t* allocator,
    apr_pool_t* pool
)

Set the owner of the allocator Typically pool is the highest level pool using the allocator

Parameters:

allocator	The allocator to set the owner for
pool	The pool that is to own the allocator

apr_pool_t*
apr_allocator_owner_get(apr_allocator_t* allocator)

Get the current owner of the allocator

Parameters:

allocator

The allocator to get the owner from

void
apr_allocator_max_free_set(
    apr_allocator_t* allocator,
    apr_size_t size
)

Set the current threshold at which the allocator should start giving blocks back to the system.

Parameters:

allocator	The allocator to set the threshold on
size	The threshold. 0 == unlimited.

void
apr_allocator_mutex_set(
    apr_allocator_t* allocator,
    apr_thread_mutex_t* mutex
)

Set a mutex for the allocator to use

Parameters:

allocator	The allocator to set the mutex for
mutex	The mutex

apr_thread_mutex_t*
apr_allocator_mutex_get(apr_allocator_t* allocator)

Get the mutex currently set for the allocator

Parameters:

allocator

The allocator

Macros

#define APR_ALLOCATOR_MAX_FREE_UNLIMITED

Symbolic constants

#define APR_MEMNODE_T_SIZE

The base size of a memory node - aligned.