gstreamer/plugins/elements/gstfakesrc.c

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/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstfakesrc.c:
*
* 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 <stdlib.h>
#include <string.h>
#include <gstfakesrc.h>
GstElementDetails gst_fakesrc_details = {
"Fake Source",
"Source",
"Push empty (no data) buffers around",
VERSION,
"Erik Walthinsen <omega@cse.ogi.edu>\n"
"Wim Taymans <wim.taymans@chello.be>",
"(C) 1999",
};
/* FakeSrc signals and args */
enum {
/* FILL ME */
SIGNAL_HANDOFF,
LAST_SIGNAL
};
enum {
ARG_0,
ARG_NUM_SOURCES,
ARG_LOOP_BASED,
ARG_OUTPUT,
ARG_DATA,
ARG_SIZETYPE,
ARG_SIZEMIN,
ARG_SIZEMAX,
ARG_FILLTYPE,
ARG_PATTERN,
ARG_NUM_BUFFERS,
ARG_EOS,
ARG_SILENT,
ARG_DUMP,
ARG_PARENTSIZE
};
GST_PADTEMPLATE_FACTORY (fakesrc_src_factory,
"src%d",
GST_PAD_SRC,
GST_PAD_REQUEST,
NULL /* no caps */
);
#define GST_TYPE_FAKESRC_OUTPUT (gst_fakesrc_output_get_type())
static GType
gst_fakesrc_output_get_type (void)
{
static GType fakesrc_output_type = 0;
static GEnumValue fakesrc_output[] = {
{ FAKESRC_FIRST_LAST_LOOP, "1", "First-Last loop"},
{ FAKESRC_LAST_FIRST_LOOP, "2", "Last-First loop"},
{ FAKESRC_PING_PONG, "3", "Ping-Pong"},
{ FAKESRC_ORDERED_RANDOM, "4", "Ordered Random"},
{ FAKESRC_RANDOM, "5", "Random"},
{ FAKESRC_PATTERN_LOOP, "6", "Patttern loop"},
{ FAKESRC_PING_PONG_PATTERN, "7", "Ping-Pong Pattern"},
{ FAKESRC_GET_ALWAYS_SUCEEDS, "8", "'_get' Always succeeds"},
{0, NULL, NULL},
};
if (!fakesrc_output_type) {
fakesrc_output_type = g_enum_register_static ("GstFakeSrcOutput", fakesrc_output);
}
return fakesrc_output_type;
}
#define GST_TYPE_FAKESRC_DATA (gst_fakesrc_data_get_type())
static GType
gst_fakesrc_data_get_type (void)
{
static GType fakesrc_data_type = 0;
static GEnumValue fakesrc_data[] = {
{ FAKESRC_DATA_ALLOCATE, "2", "Allocate data"},
{ FAKESRC_DATA_SUBBUFFER, "3", "Subbuffer data"},
{0, NULL, NULL},
};
if (!fakesrc_data_type) {
fakesrc_data_type = g_enum_register_static ("GstFakeSrcData", fakesrc_data);
}
return fakesrc_data_type;
}
#define GST_TYPE_FAKESRC_SIZETYPE (gst_fakesrc_sizetype_get_type())
static GType
gst_fakesrc_sizetype_get_type (void)
{
static GType fakesrc_sizetype_type = 0;
static GEnumValue fakesrc_sizetype[] = {
{ FAKESRC_SIZETYPE_NULL, "1", "Send empty buffers"},
{ FAKESRC_SIZETYPE_FIXED, "2", "Fixed size buffers (sizemax sized)"},
{ FAKESRC_SIZETYPE_RANDOM, "3", "Random sized buffers (sizemin <= size <= sizemax)"},
{0, NULL, NULL},
};
if (!fakesrc_sizetype_type) {
fakesrc_sizetype_type = g_enum_register_static ("GstFakeSrcSizeType", fakesrc_sizetype);
}
return fakesrc_sizetype_type;
}
#define GST_TYPE_FAKESRC_FILLTYPE (gst_fakesrc_filltype_get_type())
static GType
gst_fakesrc_filltype_get_type (void)
{
static GType fakesrc_filltype_type = 0;
static GEnumValue fakesrc_filltype[] = {
{ FAKESRC_FILLTYPE_NOTHING, "1", "Leave data as malloced"},
{ FAKESRC_FILLTYPE_NULL, "2", "Fill buffers with zeros"},
{ FAKESRC_FILLTYPE_RANDOM, "3", "Fill buffers with random crap"},
{ FAKESRC_FILLTYPE_PATTERN, "4", "Fill buffers with pattern 0x00 -> 0xff"},
{ FAKESRC_FILLTYPE_PATTERN_CONT, "5", "Fill buffers with pattern 0x00 -> 0xff that spans buffers"},
{0, NULL, NULL},
};
if (!fakesrc_filltype_type) {
fakesrc_filltype_type = g_enum_register_static ("GstFakeSrcFillType", fakesrc_filltype);
}
return fakesrc_filltype_type;
}
static void gst_fakesrc_class_init (GstFakeSrcClass *klass);
static void gst_fakesrc_init (GstFakeSrc *fakesrc);
static GstPad* gst_fakesrc_request_new_pad (GstElement *element, GstPadTemplate *templ);
static void gst_fakesrc_update_functions (GstFakeSrc *src);
static void gst_fakesrc_set_property (GObject *object, guint prop_id,
const GValue *value, GParamSpec *pspec);
static void gst_fakesrc_get_property (GObject *object, guint prop_id,
GValue *value, GParamSpec *pspec);
static GstElementStateReturn gst_fakesrc_change_state (GstElement *element);
static GstBuffer* gst_fakesrc_get (GstPad *pad);
static void gst_fakesrc_loop (GstElement *element);
static GstElementClass *parent_class = NULL;
static guint gst_fakesrc_signals[LAST_SIGNAL] = { 0 };
GType
gst_fakesrc_get_type (void)
{
static GType fakesrc_type = 0;
if (!fakesrc_type) {
static const GTypeInfo fakesrc_info = {
sizeof(GstFakeSrcClass),
NULL,
NULL,
(GClassInitFunc)gst_fakesrc_class_init,
NULL,
NULL,
sizeof(GstFakeSrc),
0,
(GInstanceInitFunc)gst_fakesrc_init,
};
fakesrc_type = g_type_register_static (GST_TYPE_ELEMENT, "GstFakeSrc", &fakesrc_info, 0);
}
return fakesrc_type;
}
static void
gst_fakesrc_class_init (GstFakeSrcClass *klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass*)klass;
gstelement_class = (GstElementClass*)klass;
parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_NUM_SOURCES,
g_param_spec_int ("num_sources", "num_sources", "num_sources",
1, G_MAXINT, 1, G_PARAM_READABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_LOOP_BASED,
g_param_spec_boolean("loop_based","loop_based","loop_based",
FALSE, G_PARAM_READWRITE)); // CHECKME
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_OUTPUT,
g_param_spec_enum("output","output","output",
GST_TYPE_FAKESRC_OUTPUT,FAKESRC_FIRST_LAST_LOOP,G_PARAM_READWRITE)); // CHECKME!
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_DATA,
g_param_spec_enum ("data", "data", "data",
GST_TYPE_FAKESRC_DATA, FAKESRC_DATA_ALLOCATE, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_SIZETYPE,
g_param_spec_enum ("sizetype", "sizetype", "sizetype",
GST_TYPE_FAKESRC_SIZETYPE, FAKESRC_SIZETYPE_NULL, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_SIZEMIN,
g_param_spec_int ("sizemin","sizemin","sizemin",
0, G_MAXINT, 0, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_SIZEMAX,
g_param_spec_int ("sizemax","sizemax","sizemax",
0, G_MAXINT, 4096, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_PARENTSIZE,
g_param_spec_int ("parentsize","parentsize","parentsize",
0, G_MAXINT, 4096 * 10, G_PARAM_READWRITE));
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_FILLTYPE,
g_param_spec_enum ("filltype", "filltype", "filltype",
GST_TYPE_FAKESRC_FILLTYPE, FAKESRC_FILLTYPE_NULL, G_PARAM_READWRITE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_PATTERN,
g_param_spec_string("pattern","pattern","pattern",
NULL, G_PARAM_READWRITE)); // CHECKME
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_NUM_BUFFERS,
g_param_spec_int("num_buffers","num_buffers","num_buffers",
G_MININT,G_MAXINT,0,G_PARAM_READWRITE)); // CHECKME
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_EOS,
g_param_spec_boolean("eos","eos","eos",
TRUE,G_PARAM_READWRITE)); // CHECKME
gst_element_install_std_props (
GST_ELEMENT_CLASS (klass),
"silent", ARG_SILENT, G_PARAM_READWRITE,
"dump", ARG_DUMP, G_PARAM_READWRITE,
NULL);
gst_fakesrc_signals[SIGNAL_HANDOFF] =
g_signal_new ("handoff", G_TYPE_FROM_CLASS(klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstFakeSrcClass, handoff), NULL, NULL,
g_cclosure_marshal_VOID__POINTER, G_TYPE_NONE, 1,
G_TYPE_POINTER);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_fakesrc_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_fakesrc_get_property);
gstelement_class->request_new_pad = GST_DEBUG_FUNCPTR (gst_fakesrc_request_new_pad);
gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_fakesrc_change_state);
}
static void
gst_fakesrc_init (GstFakeSrc *fakesrc)
{
GstPad *pad;
// set the default number of
fakesrc->numsrcpads = 1;
// create our first output pad
pad = gst_pad_new ("src", GST_PAD_SRC);
gst_element_add_pad (GST_ELEMENT (fakesrc), pad);
fakesrc->srcpads = g_slist_append (NULL, pad);
fakesrc->loop_based = FALSE;
gst_fakesrc_update_functions (fakesrc);
fakesrc->num_buffers = -1;
fakesrc->buffer_count = 0;
fakesrc->silent = FALSE;
fakesrc->dump = FALSE;
fakesrc->pattern_byte = 0x00;
fakesrc->need_flush = FALSE;
fakesrc->data = FAKESRC_DATA_ALLOCATE;
fakesrc->sizetype = FAKESRC_SIZETYPE_NULL;
fakesrc->filltype = FAKESRC_FILLTYPE_NOTHING;
fakesrc->sizemin = 0;
fakesrc->sizemax = 4096;
fakesrc->parent = NULL;
fakesrc->parentsize = 4096 * 10;
}
static GstPad*
gst_fakesrc_request_new_pad (GstElement *element, GstPadTemplate *templ)
{
gchar *name;
GstPad *srcpad;
GstFakeSrc *fakesrc;
g_return_val_if_fail (GST_IS_FAKESRC (element), NULL);
if (templ->direction != GST_PAD_SRC) {
g_warning ("gstfakesrc: request new pad that is not a SRC pad\n");
return NULL;
}
fakesrc = GST_FAKESRC (element);
name = g_strdup_printf ("src%d", fakesrc->numsrcpads);
srcpad = gst_pad_new_from_template (templ, name);
gst_element_add_pad (GST_ELEMENT (fakesrc), srcpad);
fakesrc->srcpads = g_slist_prepend (fakesrc->srcpads, srcpad);
fakesrc->numsrcpads++;
return srcpad;
}
static gboolean
gst_fakesrc_event_handler (GstPad *pad, GstEvent *event)
{
GstFakeSrc *src;
src = GST_FAKESRC (gst_pad_get_parent (pad));
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_SEEK:
g_print("fakesrc: have seek event\n");
src->buffer_count = GST_EVENT_SEEK_OFFSET (event);
if (!GST_EVENT_SEEK_FLUSH (event)) {
gst_event_free (event);
break;
}
// else we do a flush too
case GST_EVENT_FLUSH:
g_print("fakesrc: have flush event\n");
src->need_flush = TRUE;
break;
default:
g_print("fakesrc: have unhandled event\n");
break;
}
return TRUE;
}
static void
gst_fakesrc_update_functions (GstFakeSrc *src)
{
GSList *pads;
if (src->loop_based) {
gst_element_set_loop_function (GST_ELEMENT (src), GST_DEBUG_FUNCPTR (gst_fakesrc_loop));
}
else {
gst_element_set_loop_function (GST_ELEMENT (src), NULL);
}
pads = src->srcpads;
while (pads) {
GstPad *pad = GST_PAD (pads->data);
if (src->loop_based) {
gst_pad_set_get_function (pad, NULL);
}
else {
gst_pad_set_get_function (pad, GST_DEBUG_FUNCPTR (gst_fakesrc_get));
}
gst_pad_set_event_function (pad, gst_fakesrc_event_handler);
pads = g_slist_next (pads);
}
}
static void
gst_fakesrc_alloc_parent (GstFakeSrc *src)
{
GstBuffer *buf;
buf = gst_buffer_new ();
GST_BUFFER_DATA (buf) = g_malloc (src->parentsize);
GST_BUFFER_SIZE (buf) = src->parentsize;
src->parent = buf;
src->parentoffset = 0;
}
static void
gst_fakesrc_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
GstFakeSrc *src;
/* it's not null if we got it, but it might not be ours */
src = GST_FAKESRC (object);
switch (prop_id) {
case ARG_LOOP_BASED:
src->loop_based = g_value_get_boolean (value);
gst_fakesrc_update_functions (src);
break;
case ARG_OUTPUT:
break;
case ARG_DATA:
src->data = g_value_get_int (value);
switch (src->data) {
case FAKESRC_DATA_ALLOCATE:
if (src->parent) {
gst_buffer_unref (src->parent);
src->parent = NULL;
}
break;
case FAKESRC_DATA_SUBBUFFER:
if (!src->parent)
gst_fakesrc_alloc_parent (src);
default:
break;
}
break;
case ARG_SIZETYPE:
src->sizetype = g_value_get_int (value);
break;
case ARG_SIZEMIN:
src->sizemin = g_value_get_int (value);
break;
case ARG_SIZEMAX:
src->sizemax = g_value_get_int (value);
break;
case ARG_PARENTSIZE:
src->parentsize = g_value_get_int (value);
break;
case ARG_FILLTYPE:
src->filltype = g_value_get_int (value);
break;
case ARG_PATTERN:
break;
case ARG_NUM_BUFFERS:
src->num_buffers = g_value_get_int (value);
break;
case ARG_EOS:
src->eos = g_value_get_boolean (value);
GST_INFO (0, "will EOS on next buffer");
break;
case ARG_SILENT:
src->silent = g_value_get_boolean (value);
break;
case ARG_DUMP:
src->dump = g_value_get_boolean (value);
break;
default:
break;
}
}
static void
gst_fakesrc_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
{
GstFakeSrc *src;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail (GST_IS_FAKESRC (object));
src = GST_FAKESRC (object);
switch (prop_id) {
case ARG_NUM_SOURCES:
g_value_set_int (value, src->numsrcpads);
break;
case ARG_LOOP_BASED:
g_value_set_boolean (value, src->loop_based);
break;
case ARG_OUTPUT:
g_value_set_int (value, src->output);
break;
case ARG_DATA:
g_value_set_int (value, src->data);
break;
case ARG_SIZETYPE:
g_value_set_int (value, src->sizetype);
break;
case ARG_SIZEMIN:
g_value_set_int (value, src->sizemin);
break;
case ARG_SIZEMAX:
g_value_set_int (value, src->sizemax);
break;
case ARG_PARENTSIZE:
g_value_set_int (value, src->parentsize);
break;
case ARG_FILLTYPE:
g_value_set_int (value, src->filltype);
break;
case ARG_PATTERN:
g_value_set_string (value, src->pattern);
break;
case ARG_NUM_BUFFERS:
g_value_set_int (value, src->num_buffers);
break;
case ARG_EOS:
g_value_set_boolean (value, src->eos);
break;
case ARG_SILENT:
g_value_set_boolean (value, src->silent);
break;
case ARG_DUMP:
g_value_set_boolean (value, src->dump);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
Changed the way things are scheduled, especially sources. A Src used to have a push() function, and optionally a pus... Original commit message from CVS: Changed the way things are scheduled, especially sources. A Src used to have a push() function, and optionally a pushregion() to deal with async reads, etc. That whole thing has gone away, in favor of providing a pull() function for the output (Src) pad instead, ala chain functions. This makes constructing cothreaded schedules out of non-loop elements somewhat easier. Basically there was always a question as to which pad was being dealt with. In the pullregion case, cothread-specific data was used to try to pass the region struct to the right place, which is a slow hack. And in general, the push function severely limited the kind of tricks that could be played when there's more than one output pad, such as a multi-out file reader with async capabilities on each pad independently. This changes the way cothread scheduling occurs. Instead of the hack to deal with Src's by calling their push() function (or optionally the pushregion(), in certain cases), we now are working towards a general mechanism where pads are the only thing that are dealt with directly. An optimization was made in the process of doing this: the loopfunction actually run as the outer [stack] frame of the cothread is now set more intelligently in create_plan() based on what kind of element it is. We now have: loopfunc_wrapper: used for loop-based elements, it simply calls the loopfunc in a loop, paying attention to COTHREAD_STOPPING (see below). It currently does other, soon to be depracated, stuff. pullsrc_wrapper: wraps a Src that's not loop-based (since your options are now loop- or pull-based) There will be a couple more to deal with other cases, such as Connections and chain-based elements. The general idea is that it's a lot more efficient to make the decisions once in create_plan than to keep doing this huge if/else chain in the wrapper. Just choose the right wrapper up front. It'll be most apparent performance-wise in the case of whichever element context is switched to first for each iteration, since the whole wrapper setup is done for every iteration. The tricky part is that there is now a bit of overloading of the function pointers in a pad. The current meanings (possibly to change a bit more soon) are: chainfunc: as always, chainfunc pointer is mirrored between peer pads (this may change, and the chain func may end up in pushfunc) pushfunc: SrcPad: gst_pad_pushfunc_proxy, cothread_switch to peer SinkPad: none (may take over chainfunc, see below) pullfunc: SrcPad: Src or Connection's function to construct buffers SinkPad: gst_pad_pullfunc_proxy, cothread_switch to peer There are a number of issues remaining with the scheduling, not the least of which is the fact that Connections are still dealt with the old way, with _push() functions and such. I'm trying to figure out a way to unify the system so it makes sense. Following the scheduling system is hard enough, trying to change it is murder. Another useful scheduling addition, mentioned above, is COTHREAD_STOPPING. It's an element flag that's used to signal whatever code is running in cothread context that it should be finishing up and exiting soon. An example of this is in plugins/cobin/spindentity.c. All the loops should now be composed of do/while loops, rather than while(1) loops: do { buf = gst_pad_pull(spindentity->sinkpad); gst_pad_push(spindentity->srcpad,buf); } while (!GST_ELEMENT_IS_COTHREAD_STOPPING(element)); The reason for this is that COTHREAD_STOPPING may be set before the above loop ever gets started. It wouldn't do for the body of the loop to never once get called, that would simply stall the pipeline. Note that only the core library code is ever responsible for setting and unsetting this flag. All elements have to do is respond to it by cleanly exiting the loop and the function holding it. This is needed primarily to allow iterations to occur properly. Basically, there's a single entry point in the cothread scheduling loop, gst_bin_iterate_func() simply switches to this cothread. If the element in this context is allowed to loop infinitely, nothing would even switch back to the context from which the iterate() was originally called. This is a bit of a problem. The solution is for there to be an implicit switch back to the originating context. Now, even I'm not sure exactly how this works, but if the cothread that's switched to actually returns, execution returns back to the calling context, i.e. iterate_func(). COTHREAD_STOPPING is therefore set just before switching into this (currently randomly chosen) context, on the assumption that it will return promptly after finishing its duties. The burden of clearing the flag falls to the various wrapper functions provided by the Bin code, thus element writers don't have to worry about doing that at all (and simply shouldn't). Related changes: All the sources in elements/ have been changed to reflect the new system. FIXMEs: 1) gstpipeline.c calls gst_src_push at some point, dunno why, it's commented out now. 2) any other sources, including vcdsrc, dvdsrc, and v4lsrc will break badly and need to be modified to work as pull-based sources.
2000-12-04 10:52:30 +00:00
}
static void
gst_fakesrc_prepare_buffer (GstFakeSrc *src, GstBuffer *buf)
{
if (GST_BUFFER_SIZE (buf) == 0)
return;
switch (src->filltype) {
case FAKESRC_FILLTYPE_NULL:
memset (GST_BUFFER_DATA (buf), 0, GST_BUFFER_SIZE (buf));
break;
case FAKESRC_FILLTYPE_RANDOM:
{
gint i;
guint8 *ptr = GST_BUFFER_DATA (buf);
for (i = GST_BUFFER_SIZE (buf); i; i--) {
*ptr++ = (gint8)((255.0)*rand()/(RAND_MAX));
}
break;
}
case FAKESRC_FILLTYPE_PATTERN:
src->pattern_byte = 0x00;
case FAKESRC_FILLTYPE_PATTERN_CONT:
{
gint i;
guint8 *ptr = GST_BUFFER_DATA (buf);
for (i = GST_BUFFER_SIZE (buf); i; i--) {
*ptr++ = src->pattern_byte++;
}
break;
}
case FAKESRC_FILLTYPE_NOTHING:
default:
break;
}
}
static GstBuffer*
gst_fakesrc_alloc_buffer (GstFakeSrc *src, guint size)
{
GstBuffer *buf;
buf = gst_buffer_new ();
GST_BUFFER_SIZE(buf) = size;
if (size != 0) {
switch (src->filltype) {
case FAKESRC_FILLTYPE_NOTHING:
GST_BUFFER_DATA(buf) = g_malloc (size);
break;
case FAKESRC_FILLTYPE_NULL:
GST_BUFFER_DATA(buf) = g_malloc0 (size);
break;
case FAKESRC_FILLTYPE_RANDOM:
case FAKESRC_FILLTYPE_PATTERN:
case FAKESRC_FILLTYPE_PATTERN_CONT:
default:
GST_BUFFER_DATA(buf) = g_malloc (size);
gst_fakesrc_prepare_buffer (src, buf);
break;
}
}
return buf;
}
static guint
gst_fakesrc_get_size (GstFakeSrc *src)
{
guint size;
switch (src->sizetype) {
case FAKESRC_SIZETYPE_FIXED:
size = src->sizemax;
break;
case FAKESRC_SIZETYPE_RANDOM:
size = src->sizemin + (guint8)(((gfloat)src->sizemax)*rand()/(RAND_MAX + (gfloat)src->sizemin));
break;
case FAKESRC_SIZETYPE_NULL:
default:
size = 0;
break;
}
return size;
}
static GstBuffer *
gst_fakesrc_create_buffer (GstFakeSrc *src)
{
GstBuffer *buf;
guint size;
gboolean dump = src->dump;
size = gst_fakesrc_get_size (src);
if (size == 0)
return gst_buffer_new();
switch (src->data) {
case FAKESRC_DATA_ALLOCATE:
buf = gst_fakesrc_alloc_buffer (src, size);
break;
case FAKESRC_DATA_SUBBUFFER:
// see if we have a parent to subbuffer
if (!src->parent) {
gst_fakesrc_alloc_parent (src);
g_assert (src->parent);
}
// see if it's large enough
if ((GST_BUFFER_SIZE (src->parent) - src->parentoffset) >= size) {
buf = gst_buffer_create_sub (src->parent, src->parentoffset, size);
src->parentoffset += size;
}
else {
// the parent is useless now
gst_buffer_unref (src->parent);
src->parent = NULL;
// try again (this will allocate a new parent)
return gst_fakesrc_create_buffer (src);
}
gst_fakesrc_prepare_buffer (src, buf);
break;
default:
g_warning ("fakesrc: dunno how to allocate buffers !");
buf = gst_buffer_new();
break;
}
if (dump) {
gst_util_dump_mem (GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf));
}
return buf;
}
static GstBuffer *
gst_fakesrc_get(GstPad *pad)
{
Changed the way things are scheduled, especially sources. A Src used to have a push() function, and optionally a pus... Original commit message from CVS: Changed the way things are scheduled, especially sources. A Src used to have a push() function, and optionally a pushregion() to deal with async reads, etc. That whole thing has gone away, in favor of providing a pull() function for the output (Src) pad instead, ala chain functions. This makes constructing cothreaded schedules out of non-loop elements somewhat easier. Basically there was always a question as to which pad was being dealt with. In the pullregion case, cothread-specific data was used to try to pass the region struct to the right place, which is a slow hack. And in general, the push function severely limited the kind of tricks that could be played when there's more than one output pad, such as a multi-out file reader with async capabilities on each pad independently. This changes the way cothread scheduling occurs. Instead of the hack to deal with Src's by calling their push() function (or optionally the pushregion(), in certain cases), we now are working towards a general mechanism where pads are the only thing that are dealt with directly. An optimization was made in the process of doing this: the loopfunction actually run as the outer [stack] frame of the cothread is now set more intelligently in create_plan() based on what kind of element it is. We now have: loopfunc_wrapper: used for loop-based elements, it simply calls the loopfunc in a loop, paying attention to COTHREAD_STOPPING (see below). It currently does other, soon to be depracated, stuff. pullsrc_wrapper: wraps a Src that's not loop-based (since your options are now loop- or pull-based) There will be a couple more to deal with other cases, such as Connections and chain-based elements. The general idea is that it's a lot more efficient to make the decisions once in create_plan than to keep doing this huge if/else chain in the wrapper. Just choose the right wrapper up front. It'll be most apparent performance-wise in the case of whichever element context is switched to first for each iteration, since the whole wrapper setup is done for every iteration. The tricky part is that there is now a bit of overloading of the function pointers in a pad. The current meanings (possibly to change a bit more soon) are: chainfunc: as always, chainfunc pointer is mirrored between peer pads (this may change, and the chain func may end up in pushfunc) pushfunc: SrcPad: gst_pad_pushfunc_proxy, cothread_switch to peer SinkPad: none (may take over chainfunc, see below) pullfunc: SrcPad: Src or Connection's function to construct buffers SinkPad: gst_pad_pullfunc_proxy, cothread_switch to peer There are a number of issues remaining with the scheduling, not the least of which is the fact that Connections are still dealt with the old way, with _push() functions and such. I'm trying to figure out a way to unify the system so it makes sense. Following the scheduling system is hard enough, trying to change it is murder. Another useful scheduling addition, mentioned above, is COTHREAD_STOPPING. It's an element flag that's used to signal whatever code is running in cothread context that it should be finishing up and exiting soon. An example of this is in plugins/cobin/spindentity.c. All the loops should now be composed of do/while loops, rather than while(1) loops: do { buf = gst_pad_pull(spindentity->sinkpad); gst_pad_push(spindentity->srcpad,buf); } while (!GST_ELEMENT_IS_COTHREAD_STOPPING(element)); The reason for this is that COTHREAD_STOPPING may be set before the above loop ever gets started. It wouldn't do for the body of the loop to never once get called, that would simply stall the pipeline. Note that only the core library code is ever responsible for setting and unsetting this flag. All elements have to do is respond to it by cleanly exiting the loop and the function holding it. This is needed primarily to allow iterations to occur properly. Basically, there's a single entry point in the cothread scheduling loop, gst_bin_iterate_func() simply switches to this cothread. If the element in this context is allowed to loop infinitely, nothing would even switch back to the context from which the iterate() was originally called. This is a bit of a problem. The solution is for there to be an implicit switch back to the originating context. Now, even I'm not sure exactly how this works, but if the cothread that's switched to actually returns, execution returns back to the calling context, i.e. iterate_func(). COTHREAD_STOPPING is therefore set just before switching into this (currently randomly chosen) context, on the assumption that it will return promptly after finishing its duties. The burden of clearing the flag falls to the various wrapper functions provided by the Bin code, thus element writers don't have to worry about doing that at all (and simply shouldn't). Related changes: All the sources in elements/ have been changed to reflect the new system. FIXMEs: 1) gstpipeline.c calls gst_src_push at some point, dunno why, it's commented out now. 2) any other sources, including vcdsrc, dvdsrc, and v4lsrc will break badly and need to be modified to work as pull-based sources.
2000-12-04 10:52:30 +00:00
GstFakeSrc *src;
GstBuffer *buf;
g_return_val_if_fail (pad != NULL, NULL);
src = GST_FAKESRC (gst_pad_get_parent (pad));
g_return_val_if_fail (GST_IS_FAKESRC (src), NULL);
if (src->need_flush) {
src->need_flush = FALSE;
g_print("fakesrc: sending FLUSH\n");
return GST_BUFFER(gst_event_new (GST_EVENT_FLUSH));
}
if (src->num_buffers == 0) {
g_print("fakesrc: sending EOS\n");
gst_element_set_state (GST_ELEMENT (src), GST_STATE_PAUSED);
return GST_BUFFER(gst_event_new (GST_EVENT_EOS));
}
else {
if (src->num_buffers > 0)
src->num_buffers--;
}
if (src->eos) {
GST_INFO (0, "fakesrc is setting eos on pad");
g_print("fakesrc: sending EOS\n");
return GST_BUFFER(gst_event_new (GST_EVENT_EOS));
}
buf = gst_fakesrc_create_buffer (src);
GST_BUFFER_TIMESTAMP (buf) = src->buffer_count++;
if (!src->silent)
g_print("fakesrc: get ******* (%s:%s)> (%d bytes, %llu) \n",
GST_DEBUG_PAD_NAME (pad), GST_BUFFER_SIZE (buf), GST_BUFFER_TIMESTAMP (buf));
GST_DEBUG_ELEMENT (GST_CAT_DATAFLOW, src, "pre handoff emit\n");
g_signal_emit (G_OBJECT (src), gst_fakesrc_signals[SIGNAL_HANDOFF], 0,
buf, pad);
GST_DEBUG_ELEMENT (GST_CAT_DATAFLOW, src, "post handoff emit\n");
return buf;
}
/**
* gst_fakesrc_loop:
* @element: the faksesrc to loop
*
* generate an empty buffer and push it to the next element.
*/
static void
gst_fakesrc_loop(GstElement *element)
{
GstFakeSrc *src;
g_return_if_fail(element != NULL);
g_return_if_fail(GST_IS_FAKESRC(element));
src = GST_FAKESRC (element);
do {
GSList *pads;
pads = src->srcpads;
while (pads) {
GstPad *pad = GST_PAD (pads->data);
GstBuffer *buf;
if (src->num_buffers == 0) {
src->eos = TRUE;
}
else {
if (src->num_buffers > 0)
src->num_buffers--;
}
if (src->eos) {
GST_INFO (0, "fakesrc is setting eos on pad");
gst_pad_push(pad, GST_BUFFER(gst_event_new (GST_EVENT_EOS)));
return;
}
buf = gst_fakesrc_create_buffer (src);
GST_BUFFER_TIMESTAMP (buf) = src->buffer_count++;
if (!src->silent)
g_print("fakesrc: loop ******* (%s:%s) > (%d bytes, %llu) \n",
GST_DEBUG_PAD_NAME (pad), GST_BUFFER_SIZE (buf), GST_BUFFER_TIMESTAMP (buf));
g_signal_emit (G_OBJECT (src), gst_fakesrc_signals[SIGNAL_HANDOFF], 0,
buf, pad);
gst_pad_push (pad, buf);
pads = g_slist_next (pads);
}
} while (!GST_ELEMENT_IS_COTHREAD_STOPPING (element));
}
static GstElementStateReturn
gst_fakesrc_change_state (GstElement *element)
{
GstFakeSrc *fakesrc;
g_return_val_if_fail (GST_IS_FAKESRC (element), GST_STATE_FAILURE);
fakesrc = GST_FAKESRC (element);
if (GST_STATE_PENDING (element) == GST_STATE_READY) {
fakesrc->buffer_count = 0;
fakesrc->pattern_byte = 0x00;
fakesrc->need_flush = FALSE;
if (fakesrc->parent) {
gst_buffer_unref (fakesrc->parent);
fakesrc->parent = NULL;
}
}
if (GST_ELEMENT_CLASS (parent_class)->change_state)
return GST_ELEMENT_CLASS (parent_class)->change_state (element);
return GST_STATE_SUCCESS;
}
gboolean
gst_fakesrc_factory_init (GstElementFactory *factory)
{
gst_elementfactory_add_padtemplate (factory, GST_PADTEMPLATE_GET (fakesrc_src_factory));
return TRUE;
}