gstreamer/gst/gstbuffer.c
Wim Taymans bf8c785fb0 Documentation updates. All standard library objects and standard elements are documented. Modified some of the elemen...
Original commit message from CVS:
Documentation updates. All standard library objects and standard
elements are documented. Modified some of the elements to more
accuratly report about their arguments so the documentation builds
more reasonable output.
Added aviencoder and jpegencoder elements (not working yet)
2000-03-27 19:53:43 +00:00

298 lines
7.2 KiB
C

/* Gnome-Streamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <gst/gstbuffer.h>
//#define DEBUG(format,args...) g_print("DEBUG: " format, ##args)
#define DEBUG(format,args...)
GMemChunk *_gst_buffer_chunk;
void _gst_buffer_initialize() {
_gst_buffer_chunk = g_mem_chunk_new("GstBuffer",sizeof(GstBuffer),
sizeof(GstBuffer)*16,G_ALLOC_AND_FREE);
}
/**
* gst_buffer_new:
*
* Create a new buffer.
*
* Returns: new buffer
*/
GstBuffer *gst_buffer_new() {
GstBuffer *buffer;
buffer = g_mem_chunk_alloc(_gst_buffer_chunk);
DEBUG("BUF: allocating new buffer %p\n",buffer);
// g_print("allocating new mutex\n");
buffer->lock = g_mutex_new();
#ifdef HAVE_ATOMIC_H
atomic_set(&buffer->refcount,1);
#else
buffer->refcount = 1;
#endif
buffer->flags = 0;
buffer->type = 0;
buffer->data = NULL;
buffer->size = 0;
buffer->maxsize = 0;
buffer->offset = 0;
buffer->timestamp = 0;
buffer->metas = NULL;
buffer->parent = NULL;
return buffer;
}
/**
* gst_buffer_create_sub:
* @parent: parent buffer
* @offset: offset into parent buffer
* @size: size of new subbuffer
*
* Creates a sub-buffer from the parent at a given offset.
*
* Returns: new buffer
*/
GstBuffer *gst_buffer_create_sub(GstBuffer *parent,guint32 offset,guint32 size) {
GstBuffer *buffer;
g_return_val_if_fail(parent != NULL, NULL);
g_return_val_if_fail(size > 0, NULL);
g_return_val_if_fail((offset+size) <= parent->size, NULL);
buffer = g_mem_chunk_alloc(_gst_buffer_chunk);
DEBUG("BUF: allocating new subbuffer %p, parent %p\n",buffer,parent);
buffer->lock = g_mutex_new();
#ifdef HAVE_ATOMIC_H
atomic_set(&buffer->refcount,1);
#else
buffer->refcount = 1;
#endif
// copy flags and type from parent, for lack of better
buffer->flags = parent->flags;
buffer->type = parent->type;
// set the data pointer, size, offset, and maxsize
buffer->data = parent->data + offset;
buffer->size = size;
buffer->offset = offset;
buffer->maxsize = parent->size - offset;
// again, for lack of better, copy parent's timestamp
buffer->timestamp = parent->timestamp;
// no metas, this is sane I think
buffer->metas = NULL;
// set parentage and reference the parent
buffer->parent = parent;
gst_buffer_ref(parent);
// return the new subbuffer
return buffer;
}
/**
* gst_buffer_destroy:
* @buffer: the GstBuffer to destroy
*
* destroy the buffer
*/
void gst_buffer_destroy(GstBuffer *buffer) {
GSList *metas;
g_return_if_fail(buffer != NULL);
if (buffer->parent != NULL) {
DEBUG("BUF: freeing subbuffer %p\n",buffer);
}
else {
DEBUG("BUF: freeing buffer %p\n",buffer);
}
// free the data only if there is some, DONTFREE isn't set, and not sub
if (GST_BUFFER_DATA(buffer) &&
!GST_BUFFER_FLAG_IS_SET(buffer,GST_BUFFER_DONTFREE) &&
(buffer->parent == NULL)) {
g_free(GST_BUFFER_DATA(buffer));
// g_print("freed data in buffer\n");
}
// unreference any metadata attached to this buffer
metas = buffer->metas;
while (metas) {
gst_meta_unref((GstMeta *)(metas->data));
metas = g_slist_next(metas);
}
g_slist_free(buffer->metas);
// unreference the parent if there is one
if (buffer->parent != NULL)
gst_buffer_unref(buffer->parent);
g_mutex_free(buffer->lock);
//g_print("freed mutex\n");
// remove it entirely from memory
g_mem_chunk_free(_gst_buffer_chunk,buffer);
}
/**
* gst_buffer_ref:
* @buffer: the GstBuffer to reference
*
* increment the refcount of this buffer
*/
void gst_buffer_ref(GstBuffer *buffer) {
g_return_if_fail(buffer != NULL);
DEBUG("BUF: referencing buffer %p\n",buffer);
#ifdef HAVE_ATOMIC_H
//g_return_if_fail(atomic_read(&(buffer->refcount)) > 0);
atomic_inc(&(buffer->refcount))
#else
g_return_if_fail(buffer->refcount > 0);
GST_BUFFER_LOCK(buffer);
buffer->refcount++;
GST_BUFFER_UNLOCK(buffer);
#endif
}
/**
* gst_buffer_ref_by_count:
* @buffer: the GstBuffer to reference
* @count: a number
*
* increment the refcount of this buffer with count
*/
void gst_buffer_ref_by_count(GstBuffer *buffer,int count) {
g_return_if_fail(buffer != NULL);
g_return_if_fail(count > 0);
#ifdef HAVE_ATOMIC_H
g_return_if_fail(atomic_read(&(buffer->refcount)) > 0);
atomic_add(count,&(buffer->refcount))
#else
g_return_if_fail(buffer->refcount > 0);
GST_BUFFER_LOCK(buffer);
buffer->refcount += count;
GST_BUFFER_UNLOCK(buffer);
#endif
}
/**
* gst_buffer_unref:
* @buffer: the GstBuffer to unref
*
* decrement the refcount of this buffer. If the refcount is
* zero, the buffer will be destroyed.
*/
void gst_buffer_unref(GstBuffer *buffer) {
int zero;
g_return_if_fail(buffer != NULL);
DEBUG("BUF: unreferencing buffer %p\n",buffer);
#ifdef HAVE_ATOMIC_H
g_return_if_fail(atomic_read(&(buffer->refcount)) > 0);
zero = atomic_dec_and_test(&(buffer->refcount))
#else
g_return_if_fail(buffer->refcount > 0);
GST_BUFFER_LOCK(buffer);
buffer->refcount--;
zero = (buffer->refcount == 0);
GST_BUFFER_UNLOCK(buffer);
#endif
/* if we ended up with the refcount at zero, destroy the buffer */
if (zero)
gst_buffer_destroy(buffer);
}
/**
* gst_buffer_add_meta:
* @buffer: the GstBuffer to add the metadata to
* @meta: the metadata to add to this buffer
*
* add the meta data to the buffer
*/
void gst_buffer_add_meta(GstBuffer *buffer,GstMeta *meta) {
g_return_if_fail(buffer != NULL);
g_return_if_fail(meta != NULL);
gst_meta_ref(meta);
buffer->metas = g_slist_append(buffer->metas,meta);
}
/**
* gst_buffer_get_metas:
* @buffer: the GstBuffer to get the metadata from
*
* get the metadatas from the buffer
*
* Returns: a GSList of metadata
*/
GSList *gst_buffer_get_metas(GstBuffer *buffer) {
g_return_val_if_fail(buffer != NULL, NULL);
return buffer->metas;
}
/**
* gst_buffer_get_first_meta:
* @buffer: the GstBuffer to get the metadata from
*
* get the first metadata from the buffer
*
* Returns: the first metadata from the buffer
*/
GstMeta *gst_buffer_get_first_meta(GstBuffer *buffer) {
g_return_val_if_fail(buffer != NULL, NULL);
if (buffer->metas == NULL)
return NULL;
return GST_META(buffer->metas->data);
}
/**
* gst_buffer_remove_meta:
* @buffer: the GstBuffer to remove the metadata from
* @meta: the metadata to remove
*
* remove the given metadata from the buffer
*/
void gst_buffer_remove_meta(GstBuffer *buffer,GstMeta *meta) {
g_return_if_fail(buffer != NULL);
g_return_if_fail(meta != NULL);
buffer->metas = g_slist_remove(buffer->metas,meta);
gst_meta_unref(meta);
}