/* * 
 * This file is part of bufferpool
 *
 * Copyright (C) 2007 by LScube team <team@streaming.polito.it>
 * See AUTHORS for more details
 * 
 * bufferpool is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * bufferpool is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with bufferpool; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 
 *
 */

#include <sys/mman.h>
#include <errno.h>

#include <bufferpool.h>


/*! @brief This function destroys the shared memory object.
 * Firstly it unlinks the shm objects referenced in buffer and
 * then unlink them thus removing them from system.
 * It doesn't stop on the first error, but completes all operations
 * and returns the code of first error.
 * @return 0 on succes or the number of the first error occurred.
 * */
int bp_shm_destroy(BPBuffer * buffer)
{
    int unmap_err, shm_unlink_err = 0;
    char *shm_file_name;

    unmap_err = bp_shm_unmap(buffer);

    if (!
        (shm_file_name =
         bp_ipc_name(buffer->filename, BPBUFF_SHM_CTRLNAME)))
        return 1;
    if (shm_unlink(shm_file_name)) {
        switch (errno) {
        case ENOENT:
            bp_log(FNC_LOG_ERR, "SHM Object %s doesn't exists\n");
            break;
        case EACCES:
            bp_log(FNC_LOG_ERR,
                "Permission denied on SHM Object %s\n");
            break;
        default:
            bp_log(FNC_LOG_ERR,
                "Could not unlink SHM Object %s\n");
            break;
        }
        shm_unlink_err = errno;
    }
    free(shm_file_name);

    if (!
        (shm_file_name =
         bp_ipc_name(buffer->filename, BPBUFF_SHM_SLOTSNAME)))
        return 1;
    if (shm_unlink(shm_file_name)) {
        switch (errno) {
        case ENOENT:
            bp_log(FNC_LOG_ERR, "SHM Object %s doesn't exists\n");
            break;
        case EACCES:
            bp_log(FNC_LOG_ERR,
                "Permission denied on SHM Object %s\n");
            break;
        default:
            bp_log(FNC_LOG_ERR,
                "Could not unlink SHM Object %s\n");
            break;
        }
        shm_unlink_err = shm_unlink_err ? shm_unlink_err : errno;
    }
    free(shm_file_name);

    return unmap_err ? unmap_err : shm_unlink_err;
}