gstreamer/gst/icydemux/gsticydemux.c
2012-04-05 17:36:38 +02:00

640 lines
18 KiB
C

/* -*- Mode: C; tab-width: 2; indent-tabs-mode: t; c-basic-offset: 2 -*- */
/* Copyright 2005 Jan Schmidt <thaytan@mad.scientist.com>
* 2006 Michael Smith <msmith@fluendo.com>
* Copyright (C) 2003-2004 Benjamin Otte <otte@gnome.org>
*
* 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.
*/
/**
* SECTION:element-icydemux
*
* icydemux accepts data streams with ICY metadata at known intervals, as
* transmitted from an upstream element (usually read as response headers from
* an HTTP stream). The mime type of the data between the tag blocks is
* detected using typefind functions, and the appropriate output mime type set
* on outgoing buffers.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch souphttpsrc location=http://some.server/ iradio-mode=true ! icydemux ! fakesink -t
* ]| This pipeline should read any available ICY tag information and output it.
* The contents of the stream should be detected, and the appropriate mime
* type set on buffers produced from icydemux. (Using gnomevfssrc, neonhttpsrc
* or giosrc instead of souphttpsrc should also work.)
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/gst-i18n-plugin.h>
#include <gst/tag/tag.h>
#include "gsticydemux.h"
#include <string.h>
#define ICY_TYPE_FIND_MAX_SIZE (40*1024)
GST_DEBUG_CATEGORY_STATIC (icydemux_debug);
#define GST_CAT_DEFAULT (icydemux_debug)
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-icy, metadata-interval = (int)[0, MAX]")
);
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS ("ANY")
);
static void gst_icydemux_dispose (GObject * object);
static GstFlowReturn gst_icydemux_chain (GstPad * pad, GstObject * parent,
GstBuffer * buf);
static gboolean gst_icydemux_handle_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_icydemux_add_srcpad (GstICYDemux * icydemux,
GstCaps * new_caps);
static gboolean gst_icydemux_remove_srcpad (GstICYDemux * icydemux);
static GstStateChangeReturn gst_icydemux_change_state (GstElement * element,
GstStateChange transition);
static gboolean gst_icydemux_sink_setcaps (GstPad * pad, GstCaps * caps);
static gboolean gst_icydemux_send_tag_event (GstICYDemux * icydemux,
GstTagList * taglist);
#define gst_icydemux_parent_class parent_class
G_DEFINE_TYPE (GstICYDemux, gst_icydemux, GST_TYPE_ELEMENT);
static void
gst_icydemux_class_init (GstICYDemuxClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
gobject_class->dispose = gst_icydemux_dispose;
gstelement_class->change_state = gst_icydemux_change_state;
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&src_factory));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&sink_factory));
gst_element_class_set_details_simple (gstelement_class, "ICY tag demuxer",
"Codec/Demuxer/Metadata",
"Read and output ICY tags while demuxing the contents",
"Jan Schmidt <thaytan@mad.scientist.com>, "
"Michael Smith <msmith@fluendo.com>");
}
static void
gst_icydemux_reset (GstICYDemux * icydemux)
{
/* Unknown at the moment (this is a fatal error if don't have a value by the
* time we get to our chain function)
*/
icydemux->meta_interval = -1;
icydemux->remaining = 0;
icydemux->typefinding = TRUE;
gst_caps_replace (&(icydemux->src_caps), NULL);
gst_icydemux_remove_srcpad (icydemux);
if (icydemux->cached_tags) {
gst_tag_list_free (icydemux->cached_tags);
icydemux->cached_tags = NULL;
}
if (icydemux->cached_events) {
g_list_foreach (icydemux->cached_events,
(GFunc) gst_mini_object_unref, NULL);
g_list_free (icydemux->cached_events);
icydemux->cached_events = NULL;
}
if (icydemux->meta_adapter) {
gst_adapter_clear (icydemux->meta_adapter);
g_object_unref (icydemux->meta_adapter);
icydemux->meta_adapter = NULL;
}
if (icydemux->typefind_buf) {
gst_buffer_unref (icydemux->typefind_buf);
icydemux->typefind_buf = NULL;
}
if (icydemux->content_type) {
g_free (icydemux->content_type);
icydemux->content_type = NULL;
}
}
static void
gst_icydemux_init (GstICYDemux * icydemux)
{
GstElementClass *klass = GST_ELEMENT_GET_CLASS (icydemux);
icydemux->sinkpad =
gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
"sink"), "sink");
gst_pad_set_chain_function (icydemux->sinkpad,
GST_DEBUG_FUNCPTR (gst_icydemux_chain));
gst_pad_set_event_function (icydemux->sinkpad,
GST_DEBUG_FUNCPTR (gst_icydemux_handle_event));
gst_element_add_pad (GST_ELEMENT (icydemux), icydemux->sinkpad);
gst_icydemux_reset (icydemux);
}
static gboolean
gst_icydemux_sink_setcaps (GstPad * pad, GstCaps * caps)
{
GstICYDemux *icydemux = GST_ICYDEMUX (GST_PAD_PARENT (pad));
GstStructure *structure = gst_caps_get_structure (caps, 0);
const gchar *tmp;
if (!gst_structure_get_int (structure, "metadata-interval",
&icydemux->meta_interval))
return FALSE;
/* If incoming caps have the HTTP Content-Type, copy that over */
if ((tmp = gst_structure_get_string (structure, "content-type")))
icydemux->content_type = g_strdup (tmp);
/* We have a meta interval, so initialise the rest */
icydemux->remaining = icydemux->meta_interval;
icydemux->meta_remaining = 0;
return TRUE;
}
static void
gst_icydemux_dispose (GObject * object)
{
GstICYDemux *icydemux = GST_ICYDEMUX (object);
gst_icydemux_reset (icydemux);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static gboolean
gst_icydemux_add_srcpad (GstICYDemux * icydemux, GstCaps * new_caps)
{
if (icydemux->src_caps == NULL ||
!gst_caps_is_equal (new_caps, icydemux->src_caps)) {
gst_caps_replace (&(icydemux->src_caps), new_caps);
if (icydemux->srcpad != NULL) {
GST_DEBUG_OBJECT (icydemux, "Changing src pad caps to %" GST_PTR_FORMAT,
icydemux->src_caps);
gst_pad_set_caps (icydemux->srcpad, icydemux->src_caps);
}
} else {
/* Caps never changed */
gst_caps_unref (new_caps);
}
if (icydemux->srcpad == NULL) {
icydemux->srcpad =
gst_pad_new_from_template (gst_element_class_get_pad_template
(GST_ELEMENT_GET_CLASS (icydemux), "src"), "src");
g_return_val_if_fail (icydemux->srcpad != NULL, FALSE);
gst_pad_use_fixed_caps (icydemux->srcpad);
if (icydemux->src_caps)
gst_pad_set_caps (icydemux->srcpad, icydemux->src_caps);
GST_DEBUG_OBJECT (icydemux, "Adding src pad with caps %" GST_PTR_FORMAT,
icydemux->src_caps);
gst_pad_set_active (icydemux->srcpad, TRUE);
if (!(gst_element_add_pad (GST_ELEMENT (icydemux), icydemux->srcpad)))
return FALSE;
gst_element_no_more_pads (GST_ELEMENT (icydemux));
}
return TRUE;
}
static gboolean
gst_icydemux_remove_srcpad (GstICYDemux * icydemux)
{
gboolean res = TRUE;
if (icydemux->srcpad != NULL) {
res = gst_element_remove_pad (GST_ELEMENT (icydemux), icydemux->srcpad);
g_return_val_if_fail (res != FALSE, FALSE);
icydemux->srcpad = NULL;
}
return res;
};
static gchar *
gst_icydemux_unicodify (const gchar * str)
{
const gchar *env_vars[] = { "GST_ICY_TAG_ENCODING",
"GST_TAG_ENCODING", NULL
};
return gst_tag_freeform_string_to_utf8 (str, -1, env_vars);
}
/* takes ownership of tag list */
static gboolean
gst_icydemux_tag_found (GstICYDemux * icydemux, GstTagList * tags)
{
/* send the tag event if we have finished typefinding and have a src pad */
if (icydemux->srcpad)
return gst_icydemux_send_tag_event (icydemux, tags);
/* if we haven't a source pad yet, cache the tags */
if (!icydemux->cached_tags) {
icydemux->cached_tags = tags;
} else {
gst_tag_list_insert (icydemux->cached_tags, tags,
GST_TAG_MERGE_REPLACE_ALL);
gst_tag_list_free (tags);
}
return TRUE;
}
static void
gst_icydemux_parse_and_send_tags (GstICYDemux * icydemux)
{
GstTagList *tags;
const guint8 *data;
int length, i;
gchar *buffer;
gchar **strings;
length = gst_adapter_available (icydemux->meta_adapter);
data = gst_adapter_map (icydemux->meta_adapter, length);
/* Now, copy this to a buffer where we can NULL-terminate it to make things
* a bit easier, then do that parsing. */
buffer = g_strndup ((const gchar *) data, length);
tags = gst_tag_list_new_empty ();
strings = g_strsplit (buffer, "';", 0);
for (i = 0; strings[i]; i++) {
if (!g_ascii_strncasecmp (strings[i], "StreamTitle=", 12)) {
char *title = gst_icydemux_unicodify (strings[i] + 13);
if (title && *title) {
gst_tag_list_add (tags, GST_TAG_MERGE_REPLACE, GST_TAG_TITLE,
title, NULL);
g_free (title);
}
} else if (!g_ascii_strncasecmp (strings[i], "StreamUrl=", 10)) {
char *url = gst_icydemux_unicodify (strings[i] + 11);
if (url && *url) {
gst_tag_list_add (tags, GST_TAG_MERGE_REPLACE, GST_TAG_HOMEPAGE,
url, NULL);
g_free (url);
}
}
}
g_strfreev (strings);
g_free (buffer);
gst_adapter_unmap (icydemux->meta_adapter);
gst_adapter_flush (icydemux->meta_adapter, length);
if (!gst_tag_list_is_empty (tags))
gst_icydemux_tag_found (icydemux, tags);
else
gst_tag_list_free (tags);
}
static gboolean
gst_icydemux_handle_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstICYDemux *icydemux = GST_ICYDEMUX (parent);
gboolean result;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_TAG:
{
GstTagList *tags;
gst_event_parse_tag (event, &tags);
result = gst_icydemux_tag_found (icydemux, gst_tag_list_copy (tags));
gst_event_unref (event);
return result;
}
case GST_EVENT_CAPS:
{
GstCaps *caps;
gst_event_parse_caps (event, &caps);
result = gst_icydemux_sink_setcaps (pad, caps);
gst_event_unref (event);
return result;
}
default:
break;
}
if (icydemux->typefinding) {
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_STOP:
g_list_foreach (icydemux->cached_events,
(GFunc) gst_mini_object_unref, NULL);
g_list_free (icydemux->cached_events);
icydemux->cached_events = NULL;
return gst_pad_event_default (pad, parent, event);
default:
icydemux->cached_events = g_list_append (icydemux->cached_events,
event);
return TRUE;
}
} else {
return gst_pad_event_default (pad, parent, event);
}
}
static void
gst_icydemux_send_cached_events (GstICYDemux * icydemux)
{
GList *l;
for (l = icydemux->cached_events; l != NULL; l = l->next) {
GstEvent *event = GST_EVENT (l->data);
gst_pad_push_event (icydemux->srcpad, event);
}
g_list_free (icydemux->cached_events);
icydemux->cached_events = NULL;
}
static GstFlowReturn
gst_icydemux_typefind_or_forward (GstICYDemux * icydemux, GstBuffer * buf)
{
if (icydemux->typefinding) {
GstBuffer *tf_buf;
GstCaps *caps = NULL;
GstTypeFindProbability prob;
/* If we have a content-type from upstream, let's see if we can shortcut
* typefinding */
if (G_UNLIKELY (icydemux->content_type)) {
if (!g_ascii_strcasecmp (icydemux->content_type, "video/nsv")) {
GST_DEBUG ("We have a NSV stream");
caps = gst_caps_new_empty_simple ("video/x-nsv");
} else {
GST_DEBUG ("Upstream Content-Type isn't supported");
g_free (icydemux->content_type);
icydemux->content_type = NULL;
}
}
if (icydemux->typefind_buf) {
icydemux->typefind_buf = gst_buffer_append (icydemux->typefind_buf, buf);
} else {
icydemux->typefind_buf = buf;
}
/* Only typefind if we haven't already got some caps */
if (caps == NULL) {
caps = gst_type_find_helper_for_buffer (GST_OBJECT (icydemux),
icydemux->typefind_buf, &prob);
if (caps == NULL) {
if (gst_buffer_get_size (icydemux->typefind_buf) <
ICY_TYPE_FIND_MAX_SIZE) {
/* Just break for more data */
return GST_FLOW_OK;
}
/* We failed typefind */
GST_ELEMENT_ERROR (icydemux, STREAM, TYPE_NOT_FOUND, (NULL),
("No caps found for contents within an ICY stream"));
gst_buffer_unref (icydemux->typefind_buf);
icydemux->typefind_buf = NULL;
return GST_FLOW_ERROR;
}
}
if (!gst_icydemux_add_srcpad (icydemux, caps)) {
GST_DEBUG_OBJECT (icydemux, "Failed to add srcpad");
gst_caps_unref (caps);
gst_buffer_unref (icydemux->typefind_buf);
icydemux->typefind_buf = NULL;
return GST_FLOW_ERROR;
}
gst_caps_unref (caps);
if (icydemux->cached_events) {
gst_icydemux_send_cached_events (icydemux);
}
if (icydemux->cached_tags) {
gst_icydemux_send_tag_event (icydemux, icydemux->cached_tags);
icydemux->cached_tags = NULL;
}
/* Move onto streaming: call ourselves recursively with the typefind buffer
* to get that forwarded. */
icydemux->typefinding = FALSE;
tf_buf = icydemux->typefind_buf;
icydemux->typefind_buf = NULL;
return gst_icydemux_typefind_or_forward (icydemux, tf_buf);
} else {
if (G_UNLIKELY (icydemux->srcpad == NULL)) {
gst_buffer_unref (buf);
return GST_FLOW_ERROR;
}
buf = gst_buffer_make_writable (buf);
/* Most things don't care, and it's a pain to track (we should preserve a
* 0 offset on the first buffer though if it's there, for id3demux etc.) */
if (GST_BUFFER_OFFSET (buf) != 0) {
GST_BUFFER_OFFSET (buf) = GST_BUFFER_OFFSET_NONE;
}
return gst_pad_push (icydemux->srcpad, buf);
}
}
static void
gst_icydemux_add_meta (GstICYDemux * icydemux, GstBuffer * buf)
{
if (!icydemux->meta_adapter)
icydemux->meta_adapter = gst_adapter_new ();
gst_adapter_push (icydemux->meta_adapter, buf);
}
static GstFlowReturn
gst_icydemux_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
{
GstICYDemux *icydemux;
guint size, chunk, offset;
GstBuffer *sub;
GstFlowReturn ret = GST_FLOW_OK;
icydemux = GST_ICYDEMUX (parent);
if (G_UNLIKELY (icydemux->meta_interval < 0))
goto not_negotiated;
if (icydemux->meta_interval == 0) {
ret = gst_icydemux_typefind_or_forward (icydemux, buf);
goto done;
}
/* Go through the buffer, chopping it into appropriate chunks. Forward as
* tags or buffers, as appropriate
*/
size = gst_buffer_get_size (buf);
offset = 0;
while (size) {
if (icydemux->remaining) {
chunk = (size <= icydemux->remaining) ? size : icydemux->remaining;
sub = gst_buffer_copy_region (buf, GST_BUFFER_COPY_ALL, offset, chunk);
offset += chunk;
icydemux->remaining -= chunk;
size -= chunk;
/* This buffer goes onto typefinding, and/or directly pushed out */
ret = gst_icydemux_typefind_or_forward (icydemux, sub);
if (ret != GST_FLOW_OK)
goto done;
} else if (icydemux->meta_remaining) {
chunk = (size <= icydemux->meta_remaining) ?
size : icydemux->meta_remaining;
sub = gst_buffer_copy_region (buf, GST_BUFFER_COPY_ALL, offset, chunk);
gst_icydemux_add_meta (icydemux, sub);
offset += chunk;
icydemux->meta_remaining -= chunk;
size -= chunk;
if (icydemux->meta_remaining == 0) {
/* Parse tags from meta_adapter, send off as tag messages */
GST_DEBUG_OBJECT (icydemux, "No remaining metadata, parsing for tags");
gst_icydemux_parse_and_send_tags (icydemux);
icydemux->remaining = icydemux->meta_interval;
}
} else {
guint8 byte;
/* We need to read a single byte (always safe at this point in the loop)
* to figure out how many bytes of metadata exist.
* The 'spec' tells us to read 16 * (byte_value) bytes of metadata after
* this (zero is common, and means the metadata hasn't changed).
*/
gst_buffer_extract (buf, offset, &byte, 1);
icydemux->meta_remaining = 16 * byte;
if (icydemux->meta_remaining == 0)
icydemux->remaining = icydemux->meta_interval;
offset += 1;
size -= 1;
}
}
done:
gst_buffer_unref (buf);
return ret;
/* ERRORS */
not_negotiated:
{
GST_WARNING_OBJECT (icydemux, "meta_interval not set, buffer probably had "
"no caps set. Try enabling iradio-mode on the http source element");
gst_buffer_unref (buf);
return GST_FLOW_NOT_NEGOTIATED;
}
}
static GstStateChangeReturn
gst_icydemux_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstICYDemux *icydemux = GST_ICYDEMUX (element);
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_icydemux_reset (icydemux);
break;
default:
break;
}
return ret;
}
/* takes ownership of tag list */
static gboolean
gst_icydemux_send_tag_event (GstICYDemux * icydemux, GstTagList * tags)
{
GstEvent *event;
gst_element_post_message (GST_ELEMENT (icydemux),
gst_message_new_tag (GST_OBJECT (icydemux), gst_tag_list_copy (tags)));
event = gst_event_new_tag (tags);
GST_EVENT_TIMESTAMP (event) = 0;
GST_DEBUG_OBJECT (icydemux, "Sending tag event on src pad");
return gst_pad_push_event (icydemux->srcpad, event);
}
static gboolean
plugin_init (GstPlugin * plugin)
{
GST_DEBUG_CATEGORY_INIT (icydemux_debug, "icydemux", 0,
"GStreamer ICY tag demuxer");
return gst_element_register (plugin, "icydemux",
GST_RANK_PRIMARY, GST_TYPE_ICYDEMUX);
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
icydemux,
"Demux ICY tags from a stream",
plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)