--- /dev/null
+/* GStreamer
+ * Copyright (C) 2003 Christophe Fergeau <teuf@gnome.org>
+ *
+ * gstflactag.c: plug-in for reading/modifying vorbis comments in flac files
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <gst/gsttaginterface.h>
+#include <gst/tags/gsttagediting.h>
+#include <string.h>
+
+#define GST_TYPE_FLAC_TAG (gst_flac_tag_get_type())
+#define GST_FLAC_TAG(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_FLAC_TAG, GstFlacTag))
+#define GST_FLAC_TAG_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_FLAC_TAG, GstFlacTag))
+#define GST_IS_FLAC_TAG(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_FLAC_TAG))
+#define GST_IS_FLAC_TAG_CLASS(obj) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_FLAC_TAG))
+
+typedef struct _GstFlacTag GstFlacTag;
+typedef struct _GstFlacTagClass GstFlacTagClass;
+
+static inline
+gint min (gint a, gint b) {
+ if (a < b) {
+ return a;
+ } else {
+ return b;
+ }
+}
+
+
+typedef enum {
+ GST_FLAC_TAG_STATE_INIT,
+ GST_FLAC_TAG_STATE_METADATA_BLOCKS,
+ GST_FLAC_TAG_STATE_WRITING_METADATA_BLOCK,
+ GST_FLAC_TAG_STATE_SKIP_METADATA_BLOCK,
+ GST_FLAC_TAG_STATE_ADD_VORBIS_COMMENT,
+ GST_FLAC_TAG_STATE_AUDIO_DATA
+} GstFlacTagState;
+
+
+struct _GstFlacTag {
+ GstElement element;
+
+ /* pads */
+ GstPad * sinkpad;
+ GstPad * srcpad;
+
+ GstFlacTagState state;
+
+ GstBuffer * buffer;
+
+ guint metadata_bytes_remaining;
+ gboolean metadata_last_block;
+ gboolean metadata_append_vc_block;
+};
+
+struct _GstFlacTagClass {
+ GstElementClass parent_class;
+};
+
+/* elementfactory information */
+static GstElementDetails gst_flac_tag_details = GST_ELEMENT_DETAILS (
+ "flac rettager",
+ "Tag",
+ "Rewrite tags in a FLAC file",
+ "Christope Fergeau <teuf@gnome.org>"
+);
+
+
+/* signals and args */
+enum {
+ /* FILL ME */
+ LAST_SIGNAL
+};
+
+enum {
+ ARG_0,
+ /* FILL ME */
+};
+
+GST_PAD_TEMPLATE_FACTORY (flac_tag_src_template_factory,
+ "src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_CAPS_NEW (
+ "flac_tag_tag_src",
+ "audio/x-flac",
+ NULL
+ )
+)
+
+GST_PAD_TEMPLATE_FACTORY (flac_tag_sink_template_factory,
+ "sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_CAPS_NEW (
+ "flac_tag_data_sink",
+ "audio/x-flac",
+ NULL
+ )
+)
+
+
+static void gst_flac_tag_base_init (gpointer g_class);
+static void gst_flac_tag_class_init (GstFlacTagClass * klass);
+static void gst_flac_tag_init (GstFlacTag * tag);
+
+static void gst_flac_tag_chain (GstPad * pad,
+ GstData * data);
+
+static GstElementStateReturn gst_flac_tag_change_state (GstElement * element);
+
+
+static GstElementClass *parent_class = NULL;
+/* static guint gst_flac_tag_signals[LAST_SIGNAL] = { 0 }; */
+
+GType
+gst_flac_tag_get_type (void)
+{
+ static GType flac_tag_type = 0;
+
+ if (!flac_tag_type) {
+ static const GTypeInfo flac_tag_info = {
+ sizeof (GstFlacTagClass),
+ gst_flac_tag_base_init,
+ NULL,
+ (GClassInitFunc) gst_flac_tag_class_init,
+ NULL,
+ NULL,
+ sizeof (GstFlacTag),
+ 0,
+ (GInstanceInitFunc) gst_flac_tag_init,
+ };
+ static const GInterfaceInfo tag_setter_info = {
+ NULL,
+ NULL,
+ NULL
+ };
+
+ flac_tag_type = g_type_register_static(GST_TYPE_ELEMENT, "GstFlacTag", &flac_tag_info, 0);
+
+ g_type_add_interface_static (flac_tag_type, GST_TYPE_TAG_SETTER, &tag_setter_info);
+
+ }
+ return flac_tag_type;
+}
+
+
+static void
+gst_flac_tag_base_init (gpointer g_class)
+{
+ GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+ gst_element_class_set_details (element_class, &gst_flac_tag_details);
+
+ gst_element_class_add_pad_template (element_class,
+ GST_PAD_TEMPLATE_GET (flac_tag_sink_template_factory));
+ gst_element_class_add_pad_template (element_class,
+ GST_PAD_TEMPLATE_GET (flac_tag_src_template_factory));
+}
+
+
+static void
+gst_flac_tag_class_init (GstFlacTagClass *klass)
+{
+ GstElementClass *gstelement_class;
+ GObjectClass *gobject_class;
+
+ gstelement_class = (GstElementClass*) klass;
+ gobject_class = (GObjectClass*) klass;
+
+ parent_class = g_type_class_ref(GST_TYPE_ELEMENT);
+
+ gstelement_class->change_state = gst_flac_tag_change_state;
+}
+
+
+static void
+gst_flac_tag_init (GstFlacTag *tag)
+{
+ /* create the sink and src pads */
+ tag->sinkpad = gst_pad_new_from_template(
+ GST_PAD_TEMPLATE_GET (flac_tag_sink_template_factory), "sink");
+ gst_element_add_pad (GST_ELEMENT (tag), tag->sinkpad);
+ gst_pad_set_chain_function (tag->sinkpad, GST_DEBUG_FUNCPTR (gst_flac_tag_chain));
+
+ tag->srcpad = gst_pad_new_from_template(
+ GST_PAD_TEMPLATE_GET (flac_tag_src_template_factory), "src");
+ gst_element_add_pad (GST_ELEMENT (tag), tag->srcpad);
+
+ tag->buffer = NULL;
+}
+
+#define FLAC_MAGIC "fLaC"
+#define FLAC_MAGIC_SIZE (sizeof (FLAC_MAGIC) - 1)
+
+static void
+gst_flac_tag_chain (GstPad *pad, GstData *data)
+{
+ GstBuffer *buffer;
+ GstFlacTag *tag;
+
+ if (GST_IS_EVENT (data)) {
+ g_print ("Unhandled event\n");
+ return;
+ }
+
+ buffer = GST_BUFFER (data);
+ tag = GST_FLAC_TAG (gst_pad_get_parent (pad));
+
+ if (tag->buffer) {
+ tag->buffer = gst_buffer_merge (tag->buffer, buffer);
+ } else {
+ tag->buffer = buffer;
+ }
+
+
+ /* Initial state, we don't even know if we are dealing with a flac file */
+ if (tag->state == GST_FLAC_TAG_STATE_INIT) {
+ if (GST_BUFFER_SIZE (tag->buffer) < sizeof (FLAC_MAGIC)) {
+ return;
+ }
+
+ if (strncmp (GST_BUFFER_DATA (tag->buffer), FLAC_MAGIC, FLAC_MAGIC_SIZE) == 0) {
+ GstBuffer *sub;
+ tag->state = GST_FLAC_TAG_STATE_METADATA_BLOCKS;
+ sub = gst_buffer_create_sub (tag->buffer, 0, FLAC_MAGIC_SIZE);
+
+ gst_pad_push (tag->srcpad, GST_DATA (sub));
+ sub = gst_buffer_create_sub (tag->buffer, FLAC_MAGIC_SIZE, GST_BUFFER_SIZE (tag->buffer) - FLAC_MAGIC_SIZE);
+ gst_buffer_unref (tag->buffer);
+ /* We do a copy because we need a writable buffer, and _create_sub
+ * sets the buffer it uses to read-only
+ */
+ tag->buffer = gst_buffer_copy (sub);
+ gst_buffer_unref (sub);
+ } else {
+ /* FIXME: does that work well with FLAC files containing ID3v2 tags ? */
+ gst_element_error (GST_ELEMENT (tag), "Not a flac stream\n");
+ }
+
+ /* We must know if we'll add a vorbiscomment block as the last metadata
+ * block as soon as possible: if we won't add a block by ourselves,
+ * we must keep the current vorbiscomment block, and don't change
+ * the "last block" flag when we read it
+ */
+ tag->metadata_append_vc_block = (gst_tag_setter_get_list (GST_TAG_SETTER (tag)) != NULL);
+ }
+
+ /* The fLaC magic string has been skipped, try to detect the beginning
+ * of a metadata block
+ */
+ if (tag->state == GST_FLAC_TAG_STATE_METADATA_BLOCKS) {
+ guint size;
+ guint type;
+ gboolean is_last;
+
+ g_assert (tag->metadata_bytes_remaining == 0);
+ g_assert (tag->metadata_last_block == FALSE);
+
+ /* The header of a flac metadata block is 4 bytes long:
+ * 1st bit: indicates whether this is the last metadata info block
+ * 7 next bits: 4 if vorbis comment block
+ * 24 next bits: size of the metadata to follow (big endian)
+ */
+ if (GST_BUFFER_SIZE (tag->buffer) < 4) {
+ return;
+ }
+ is_last = (((GST_BUFFER_DATA (tag->buffer)[0]) & 0x80) == 0x80);
+ /* If we have metadata set on the element, the last metadata block
+ * will be the vorbis comment block which we will build ourselves
+ */
+ if ((is_last) && (tag->metadata_append_vc_block)) {
+ (GST_BUFFER_DATA (tag->buffer)[0]) &= (~0x80);
+ }
+
+ type = (GST_BUFFER_DATA (tag->buffer)[0]) & 0x7F;
+ size =
+ ((GST_BUFFER_DATA (tag->buffer)[1]) << 16)
+ | ((GST_BUFFER_DATA (tag->buffer)[2]) << 8)
+ | (GST_BUFFER_DATA (tag->buffer)[3]);
+
+ /* The 4 bytes long header isn't included in the metadata size */
+ tag->metadata_bytes_remaining = size + 4;
+ tag->metadata_last_block = is_last;
+
+ /* Metadata blocks of type 4 are vorbis comment blocks */
+ if ((type == 0x04) && (tag->metadata_append_vc_block)) {
+ tag->state = GST_FLAC_TAG_STATE_SKIP_METADATA_BLOCK;
+ } else {
+ tag->state = GST_FLAC_TAG_STATE_WRITING_METADATA_BLOCK;
+ }
+ }
+
+ /* Reads a metadata block */
+ if ((tag->state == GST_FLAC_TAG_STATE_WRITING_METADATA_BLOCK) ||
+ (tag->state == GST_FLAC_TAG_STATE_SKIP_METADATA_BLOCK)) {
+ guint bytes_to_push;
+
+ g_assert (tag->metadata_bytes_remaining != 0);
+
+ bytes_to_push = min (tag->metadata_bytes_remaining,
+ GST_BUFFER_SIZE (tag->buffer));
+
+ if (tag->state == GST_FLAC_TAG_STATE_WRITING_METADATA_BLOCK) {
+ GstBuffer *sub;
+ sub = gst_buffer_create_sub (tag->buffer, 0, bytes_to_push);
+ gst_pad_push (tag->srcpad, GST_DATA (sub));
+ }
+ tag->metadata_bytes_remaining -= (bytes_to_push);
+
+ if (GST_BUFFER_SIZE (tag->buffer) > bytes_to_push) {
+ GstBuffer *sub;
+
+ sub = gst_buffer_create_sub (tag->buffer, bytes_to_push,
+ GST_BUFFER_SIZE (tag->buffer) - bytes_to_push);
+ gst_buffer_unref (tag->buffer);
+
+ /* We do a copy because we need a writable buffer, and _create_sub
+ * sets the buffer it uses to read-only
+ */
+ tag->buffer = gst_buffer_copy (sub);
+ gst_buffer_unref (sub);
+
+ if (tag->metadata_last_block == FALSE) {
+ tag->state = GST_FLAC_TAG_STATE_METADATA_BLOCKS;
+ } else if (tag->metadata_append_vc_block) {
+ tag->state = GST_FLAC_TAG_STATE_ADD_VORBIS_COMMENT;
+ } else {
+ tag->state = GST_FLAC_TAG_STATE_AUDIO_DATA;
+ }
+ } else if (tag->metadata_bytes_remaining == 0) {
+ tag->state = GST_FLAC_TAG_STATE_METADATA_BLOCKS;
+ tag->buffer = NULL;
+ } else {
+ tag->state = GST_FLAC_TAG_STATE_WRITING_METADATA_BLOCK;
+ tag->buffer = NULL;
+ }
+ }
+
+ /* Creates a vorbis comment block from the metadata which was set
+ * on the gstreamer element, and add it to the flac stream
+ */
+ if (tag->state == GST_FLAC_TAG_STATE_ADD_VORBIS_COMMENT) {
+ guchar header[4];
+ GstBuffer *buffer;
+ gint size;
+ const GstTagList *tags;
+
+ g_assert (tag->metadata_append_vc_block);
+ bzero (header, sizeof (header));
+ header[0] = 0x84; /* 0x80 = Last metadata block,
+ * 0x04 = vorbiscomment block
+ */
+ tags = gst_tag_setter_get_list (GST_TAG_SETTER (tag));
+ buffer = gst_tag_list_to_vorbiscomment_buffer (tags, header,
+ sizeof (header), NULL);
+ if (buffer == NULL) {
+ gst_element_error (GST_ELEMENT (tag), "Error filling vorbis comments\n");
+ return;
+ }
+ size = GST_BUFFER_SIZE (buffer) - sizeof (header);
+ if ((size > 0xFFFFFF) || (size < 4)) {
+ /* FLAC vorbis comment blocks are limited to 2^24 bytes,
+ * while the vorbis specs allow more than that. Shouldn't
+ * be a real world problem though
+ */
+ gst_element_error (GST_ELEMENT (tag), "Vorbis comment too long\n");
+ return;
+ }
+ GST_BUFFER_DATA (buffer)[1] = ((size & 0xFF0000) >> 16);
+ GST_BUFFER_DATA (buffer)[2] = ((size & 0x00FF00) >> 8);
+ GST_BUFFER_DATA (buffer)[3] = (size & 0x0000FF);
+ gst_pad_push (tag->srcpad, GST_DATA (buffer));
+ tag->state = GST_FLAC_TAG_STATE_AUDIO_DATA;
+ }
+
+ /* The metadata blocks have been read, now we are reading audio data */
+ if (tag->state == GST_FLAC_TAG_STATE_AUDIO_DATA) {
+ gst_pad_push (tag->srcpad, GST_DATA (tag->buffer));
+ tag->buffer = NULL;
+ }
+}
+
+
+static GstElementStateReturn
+gst_flac_tag_change_state (GstElement *element)
+{
+ GstFlacTag *tag;
+
+ tag = GST_FLAC_TAG (element);
+
+ switch (GST_STATE_TRANSITION (element)) {
+ case GST_STATE_NULL_TO_READY:
+ break;
+ case GST_STATE_READY_TO_PAUSED:
+ break;
+ case GST_STATE_PAUSED_TO_PLAYING:
+ /* do something to get out of the chain function faster */
+ break;
+ case GST_STATE_PLAYING_TO_PAUSED:
+ break;
+ case GST_STATE_PAUSED_TO_READY:
+ if (tag->buffer) {
+ gst_buffer_unref (tag->buffer);
+ tag->buffer = NULL;
+ }
+ tag->state = GST_FLAC_TAG_STATE_INIT;
+ break;
+ case GST_STATE_READY_TO_NULL:
+ break;
+ }
+
+ return parent_class->change_state (element);
+}
projects / platform / upstream / gst-plugins-good.git / commitdiff