/* * 
 * 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 <string.h>
#include <bufferpool.h>

/*! @brief Write a new slot in the buffer using the input parameters.
 *
 *  The function writes a new slot according with input parameters. If the
 *  <tt>data</tt> belongs to a slot that was previously requested with
 *  <tt>bp_getslot</tt> then there is not copy of data, just the
 *  parameter setting like a commit of changes done.
 *  @param seq_delta is the difference between sequence number of pkt(slot) and
 *  the expected number. If it's 0, it does mean that the sequence number is
 *  grown by 1.
 *  @return ERR_NOERROR or ERR_ALLOC
 *  */
int bp_write(BPBuffer * buffer, int16_t seq_delta, double timestamp,
                  uint32_t rtp_time, uint8_t marker, uint8_t * data, 
                  uint32_t data_size)
{
    BPSlot *slot; // = &buffer->slots[buffer->control->write_pos];
    uint64_t curr_seq; // = slot->slot_seq;

    bp_lock(buffer);

    if (bp_shm_refresh(buffer))
        return ERR_ALLOC;

    slot = &buffer->slots[buffer->control->write_pos];
    curr_seq = slot->slot_seq;

    if (buffer->slots[slot->next].data == data) {
        slot = &buffer->slots[slot->next];
    } else {
        if (buffer->slots[slot->next].refs > 0) {
            if ((slot = bp_addpage(buffer, slot)) == NULL) {
                bp_unlock(buffer);
                return ERR_ALLOC;
            }
        } else {
            slot = &buffer->slots[slot->next];
        }

        memcpy(slot->data, data, data_size);
    }

    slot->timestamp = timestamp;
    slot->rtp_time = rtp_time;
    slot->marker = marker;
    slot->data_size = data_size;

    slot->refs = buffer->control->refs;
    slot->slot_seq = curr_seq + 1;
    slot->seq_delta = seq_delta + 1;

    buffer->control->write_pos = BPtoSlotPtr(buffer, slot);

    bp_dump(NULL, buffer);

    bp_unlock(buffer);

    return ERR_NOERROR;
}