shmem.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

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#include "mm.h"
#include "apr_general.h"
#include "apr_shmem.h"
#include "apr_errno.h"

#if BEOS
#include <kernel/OS.h>
#endif

struct shmem_t {
    MM *mm;
#if BEOS
    area_id id;
#endif
};

apr_status_t apr_shm_init(struct shmem_t **m, apr_size_t reqsize, const char *file, apr_pool_t *cont)
{
    MM *newmm = mm_create(reqsize + sizeof(**m), file, MM_ALLOCATE_ENOUGH);
    if (newmm == NULL) {
        return errno;
    }
    (*m) = mm_malloc(newmm, sizeof(struct shmem_t));
    /* important to check this; we may be locking a lock file for the first
     * time, which won't work if the file is on NFS
     */
    if (!*m) {
        return errno;
    }
    (*m)->mm = newmm;
#if BEOS
    (*m)->id = area_for((*m));
#endif
    return APR_SUCCESS;
}

apr_status_t apr_shm_destroy(struct shmem_t *m)
{
    mm_destroy(m->mm);
    return APR_SUCCESS;
}

void *apr_shm_malloc(struct shmem_t *c, apr_size_t reqsize)
{
    if (c->mm == NULL) {
        return NULL;
    }
    return mm_malloc(c->mm, reqsize);
}

void *apr_shm_calloc(struct shmem_t *shared, apr_size_t size) 
{
    if (shared == NULL) {
        return NULL;
    }
    return mm_calloc(shared->mm, 1, size);
}

apr_status_t apr_shm_free(struct shmem_t *shared, void *entity)
{
    mm_free(shared->mm, entity);
    return APR_SUCCESS;
}

apr_status_t apr_shm_name_get(apr_shmem_t *c, apr_shm_name_t **name)
{
#if APR_USES_ANONYMOUS_SHM
    *name = NULL;
    return APR_ANONYMOUS;
/* Currently, we are not supporting name based shared memory on Unix
 * systems.  This may change in the future however, so I will leave
 * this in here for now.  Plus, this gives other platforms a good idea
 * of how to proceed.
 */
#elif APR_USES_FILEBASED_SHM
#elif APR_USES_KEYBASED_SHM
#endif
}

apr_status_t apr_shm_name_set(apr_shmem_t *c, apr_shm_name_t *name)
{
#if APR_USES_ANONYMOUS_SHM
    return APR_ANONYMOUS;
/* Currently, we are not supporting name based shared memory on Unix
 * systems.  This may change in the future however, so I will leave
 * this in here for now.  Plus, this gives other platforms a good idea
 * of how to proceed.
 */
#elif APR_USES_FILEBASED_SHM
#elif APR_USES_KEYBASED_SHM
#endif
}

apr_status_t apr_shm_open(struct shmem_t *c)
{
#if APR_USES_ANONYMOUS_SHM

#if BEOS
    /* If we've forked we need a clone of the original area or we
     * will only have access to a one time copy of the data made when
     * the fork occurred.  This strange bit of code fixes that problem!
     */
    thread_info ti;
    area_info ai;
    area_id deleteme = area_for(c);
    
    /* we need to check which team we're in, so we need to get
     * the appropriate info structures for the current thread and
     * the area we're using.
     */
    get_area_info(c->id, &ai);   
    get_thread_info(find_thread(NULL), &ti);

    if (ti.team != ai.team){
        area_id nai;
        /* if we are in a child then we need to delete the system
         * created area as it's a one time copy and won't be a clone
         * which is not good.
         */
        delete_area(deleteme);
        /* now we make our own clone and use that from now on! */
        nai = clone_area(ai.name, &(ai.address), B_CLONE_ADDRESS,
            B_READ_AREA | B_WRITE_AREA, ai.area);
        get_area_info(nai, &ai);
        c = ai.address;
    }
#endif
/* When using MM, we don't need to open shared memory segments in child
 * segments, so just return immediately.
 */
    return APR_SUCCESS;
/* Currently, we are not supporting name based shared memory on Unix
 * systems.  This may change in the future however, so I will leave
 * this in here for now.  Plus, this gives other platforms a good idea
 * of how to proceed.
 */
#elif APR_USES_FILEBASED_SHM
#elif APR_USES_KEYBASED_SHM
#endif
}

apr_status_t apr_shm_avail(struct shmem_t *c, apr_size_t *size)
{
    *size = mm_available(c);
    if (*size == 0) {
        return APR_ENOSHMAVAIL;
    }
    return APR_SUCCESS;
}