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/*
* Copyright (C) 2008 Julian Scheel
*
* This file is part of xine, a free video player.
*
* xine is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* xine 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
*
* nal.c: nal-structure utility functions
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "nal.h"
#include <xine/xine_internal.h>
struct nal_buffer* create_nal_buffer(uint8_t max_size)
{
struct nal_buffer *nal_buffer = calloc(1, sizeof(struct nal_buffer));
nal_buffer->max_size = max_size;
return nal_buffer;
}
/**
* destroys a nal buffer. all referenced nals are released
*/
void free_nal_buffer(struct nal_buffer *nal_buffer)
{
struct nal_unit *nal = nal_buffer->first;
while (nal) {
struct nal_unit *delete = nal;
nal = nal->next;
release_nal_unit(delete);
}
free(nal_buffer);
}
/**
* appends a nal unit to the end of the buffer
*/
void nal_buffer_append(struct nal_buffer *nal_buffer, struct nal_unit *nal)
{
if(nal_buffer->used == nal_buffer->max_size) {
nal_buffer_remove(nal_buffer, nal_buffer->first);
}
if (nal_buffer->first == NULL) {
nal_buffer->first = nal_buffer->last = nal;
nal->prev = nal->next = NULL;
lock_nal_unit(nal);
nal_buffer->used++;
} else if (nal_buffer->last != NULL) {
nal_buffer->last->next = nal;
nal->prev = nal_buffer->last;
nal_buffer->last = nal;
lock_nal_unit(nal);
nal_buffer->used++;
} else {
lprintf("ERR: nal_buffer is in a broken state\n");
}
}
void nal_buffer_remove(struct nal_buffer *nal_buffer, struct nal_unit *nal)
{
if (nal == nal_buffer->first && nal == nal_buffer->last) {
nal_buffer->first = nal_buffer->last = NULL;
} else {
if (nal == nal_buffer->first) {
nal_buffer->first = nal->next;
nal_buffer->first->prev = NULL;
} else {
nal->prev->next = nal->next;
}
if (nal == nal_buffer->last) {
nal_buffer->last = nal->prev;
nal_buffer->last->next = NULL;
} else {
nal->next->prev = nal->prev;
}
}
nal->next = nal->prev = NULL;
release_nal_unit(nal);
nal_buffer->used--;
}
void nal_buffer_flush(struct nal_buffer *nal_buffer)
{
while(nal_buffer->used > 0) {
nal_buffer_remove(nal_buffer, nal_buffer->first);
}
}
/**
* returns the last element in the buffer
*/
struct nal_unit *nal_buffer_get_last(struct nal_buffer *nal_buffer)
{
return nal_buffer->last;
}
/**
* get a nal unit from a nal_buffer from it's
* seq parameter_set_id
*/
struct nal_unit* nal_buffer_get_by_sps_id(struct nal_buffer *nal_buffer,
uint32_t seq_parameter_set_id)
{
struct nal_unit *nal = nal_buffer->last;
if (nal != NULL) {
do {
if(nal->nal_unit_type == NAL_SPS) {
if(nal->sps.seq_parameter_set_id == seq_parameter_set_id) {
return nal;
}
}
nal = nal->prev;
} while(nal != NULL);
}
return NULL;
}
/**
* get a nal unit from a nal_buffer from it's
* pic parameter_set_id
*/
struct nal_unit* nal_buffer_get_by_pps_id(struct nal_buffer *nal_buffer,
uint32_t pic_parameter_set_id)
{
struct nal_unit *nal = nal_buffer->last;
if (nal != NULL) {
do {
if(nal->nal_unit_type == NAL_PPS) {
if(nal->pps.pic_parameter_set_id == pic_parameter_set_id) {
return nal;
}
}
nal = nal->prev;
} while(nal != NULL);
}
return NULL;
}
/**
* create a new nal unit, with a lock_counter of 1
*/
struct nal_unit* create_nal_unit()
{
struct nal_unit *nal = calloc(1, sizeof(struct nal_unit));
nal->lock_counter = 1;
return nal;
}
void lock_nal_unit(struct nal_unit *nal)
{
nal->lock_counter++;
}
void release_nal_unit(struct nal_unit *nal)
{
if(!nal)
return;
nal->lock_counter--;
if(nal->lock_counter <= 0) {
free(nal);
}
}
/**
* creates a copy of a nal unit with a single lock
*/
void copy_nal_unit(struct nal_unit *dest, struct nal_unit *src)
{
/* size without pps, sps and slc units: */
int size = sizeof(struct nal_unit);
xine_fast_memcpy(dest, src, size);
dest->lock_counter = 1;
dest->prev = dest->next = NULL;
}