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/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
#ifndef APR_SHMEM_H
#define APR_SHMEM_H
/**
* @package Shared Memory library
*/
#include "apr.h"
#include "apr_pools.h"
#include "apr_errno.h"
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#if APR_USES_FILEBASED_SHM
typedef char * apr_shm_name_t;
#elif APR_USES_KEYBASED_SHM
typedef key_t apr_shm_name_t;
#else
/* If APR_USES_ANONYMOUS_SHM or any other case...
* we can't leave apr_shm_name_t entirely undefined.
*/
typedef void apr_shm_name_t;
#endif
typedef struct shmem_t apr_shmem_t;
/**
* Create a pool of shared memory for use later.
* @param m The shared memory block.
* @param reqsize The size of the shared memory pool.
* @param file The file to use for the shared memory on platforms
* that require it.
* @param cont The pool to use
*/
apr_status_t apr_shm_init(apr_shmem_t **m, apr_size_t reqsize, const char *file, apr_pool_t *cont);
/**
* Destroy the shared memory block.
* @param m The shared memory block to destroy.
*/
apr_status_t apr_shm_destroy(apr_shmem_t *m);
/**
* allocate memory from the block of shared memory.
* @param c The shared memory block to destroy.
* @param reqsize How much memory to allocate
*/
void *apr_shm_malloc(apr_shmem_t *c, apr_size_t reqsize);
/**
* allocate memory from the block of shared memory and initialize it to zero.
* @param shared The shared memory block to destroy.
* @param size How much memory to allocate
*/
void *apr_shm_calloc(apr_shmem_t *shared, apr_size_t size);
/**
* free shared memory previously allocated.
* @param shared The shared memory block to destroy.
* @param entity The actual data to free.
*/
apr_status_t apr_shm_free(apr_shmem_t *shared, void *entity);
/**
* Get the name of the shared memory segment if not using anonymous
* shared memory.
* @param c The shared memory block to destroy.
* @param name The name of the shared memory block, NULL if anonymous
* shared memory.
* @return APR_USES_ANONYMOUS_SHM if we are using anonymous shared
* memory. APR_USES_FILEBASED_SHM if our shared memory is
* based on file access. APR_USES_KEYBASED_SHM if shared
* memory is based on a key value such as shmctl. If the
* shared memory is anonymous, the name is NULL.
*/
apr_status_t apr_get_shm_name(apr_shmem_t *c, apr_shm_name_t **name);
/**
* Set the name of the shared memory segment if not using anonymous
* shared memory. This is to allow processes to open shared memory
* created by another process.
* @param c The shared memory block to destroy.
* @param name The name of the shared memory block, NULL if anonymous
* shared memory.
* @return APR_USES_ANONYMOUS_SHM if we are using anonymous shared
* memory. APR_SUCCESS if we are using named shared memory
* and we were able to assign the name correctly.
*/
apr_status_t apr_set_shm_name(apr_shmem_t *c, apr_shm_name_t *name);
/**
* Open the shared memory block in a child process.
* @param The shared memory block to open in the child.
*/
apr_status_t apr_open_shmem(apr_shmem_t *c);
/**
* Determine how much memory is available in the specified shared memory block
* @param c The shared memory block to open in the child.
* @param avail The amount of space available in the shared memory block.
*/
apr_status_t apr_shm_avail(apr_shmem_t *c, apr_size_t *avail);
#ifdef __cplusplus
}
#endif
#endif /* ! APR_SHMEM_H */
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