/* ====================================================================
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#ifndef APR_SHMEM_H
#define APR_SHMEM_H

#include "apr.h"
#include "apr_general.h"
#include "apr_errno.h"

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

#if APR_USES_ANONYMOUS_SHM
typedef   void           ap_shm_name_t;
#elif APR_USES_FILEBASED_SHM
typedef   char *         ap_shm_name_t;
#elif APR_USES_KEYBASED_SHM
typedef   key_t          ap_shm_name_t;
#endif

typedef   struct shmem_t ap_shmem_t;

/*

=head1 ap_status_t ap_shm_init(ap_shmem_t *m, ap_size_t reqsize, char *file)

B<Create a pool of shared memory for use later.>

    arg 1) The shared memory block.
    arg 2) The size of the shared memory pool.
    arg 3) The file to use for the shared memory on platforms that
           require it.
    arg 4) The pool to use

=cut
 */
ap_status_t ap_shm_init(ap_shmem_t **m, ap_size_t reqsize, const char *file, ap_pool_t *cont);

/*

=head1 ap_status_t ap_shm_destroy(ap_shmem_t *m)

B<Destroy the shared memory block.>

    arg 1) The shared memory block to destroy. 

=cut
 */
ap_status_t ap_shm_destroy(ap_shmem_t *m);

/*

=head1 ap_status_t ap_shm_malloc(ap_shmem_t *c, ap_size_t reqsize)

B<allocate memory from the block of shared memory.>

    arg 1) The shared memory block to destroy. 
    arg 2) How much memory to allocate

=cut
 */
void *ap_shm_malloc(ap_shmem_t *c, ap_size_t reqsize);

/*

=head1 void *ap_shm_calloc(ap_shmem_t *shared, ap_size_t size)

B<allocate memory from the block of shared memory and initialize it to zero.>

    arg 1) The shared memory block to destroy. 
    arg 2) How much memory to allocate

=cut
 */
void *ap_shm_calloc(ap_shmem_t *shared, ap_size_t size);

/*

=head1 ap_status_t ap_shm_free(ap_shmem_t *shared, void *entity)

B<free shared memory previously allocated.>

    arg 1) The shared memory block to destroy. 

=cut
 */
ap_status_t ap_shm_free(ap_shmem_t *shared, void *free);

/*

=head1 ap_status_t ap_get_shm_name(ap_shmem_t *c, ap_shm_name_t **name)

B<Get the name of the shared memory segment if not using anonymous shared memory.>

    arg 1)  The shared memory block to destroy. 
    arg 2)  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.

=cut
 */
ap_status_t ap_get_shm_name(ap_shmem_t *c, ap_shm_name_t **name);

/*

=head1 ap_status_t ap_set_shm_name(ap_shmem_t *c, ap_shm_name_t *name)

B<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.

    arg 1)  The shared memory block to destroy. 
    arg 2)  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. 

=cut
 */
ap_status_t ap_set_shm_name(ap_shmem_t *c, ap_shm_name_t *name);

/*

=head1 ap_status_t ap_open_shmem(ap_shmem_t *c)

B<Open the shared memory block in a child process.> 

    arg 1)  The shared memory block to open in the child. 
   return) This should be called after ap_set_shm_name.  The ap_shmem_t 
           variable must refer to the memory segment to open.

=cut
 */
ap_status_t ap_open_shmem(ap_shmem_t *c);

/*

=head1 ap_status_t ap_shm_avail(ap_shmem_t *c, ap_size_t *size)

B<Determine how much memory is available in the specified shared memory block>

    arg 1)  The shared memory block to open in the child. 
    arg 2)  The amount of space available in the shared memory block.

=cut
 */
ap_status_t ap_shm_avail(ap_shmem_t *c, ap_size_t *avail);

#ifdef __cplusplus
}
#endif

#endif  /* ! APR_FILE_IO_H */