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diff --git a/gst/apetag/gstapedemux.c b/gst/apetag/gstapedemux.c
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+/* GStreamer APEv1/2 tag reader
+ * Copyright (C) 2004 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ * Copyright (C) 2006 Tim-Philipp Müller <tim centricular net>
+ *
+ * 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-apedemux
+ * @short_description: reads tag information from APE tag data blocks and
+ * outputs them as GStreamer tag messages and events.
+ *
+ * <refsect2>
+ * <para>
+ * apedemux accepts data streams with APE tags at the start or at the end
+ * (or both). 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.
+ * </para>
+ * <para>
+ * The element is only able to read APE tags at the end of a stream from
+ * a seekable stream, ie. when get_range mode is supported by the upstream
+ * elements. If get_range operation is available, apedemux makes it available
+ * downstream. This means that elements which require get_range mode, such as
+ * wavparse or musepackdec, can operate on files containing APE tag
+ * information.
+ * </para>
+ * <title>Example launch line</title>
+ * <para>
+ * <programlisting>
+ * gst-launch -t filesrc location=file.mpc ! apedemux ! fakesink
+ * </programlisting>
+ * This pipeline should read any available APE tag information and output it.
+ * The contents of the file inside the APE tag regions should be detected, and
+ * the appropriate mime type set on buffers produced from apedemux.
+ * </para>
+ * </refsect2>
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/gst-i18n-plugin.h>
+
+#include "gstapedemux.h"
+
+#include <string.h>
+
+#define APE_VERSION_MAJOR(ver) ((ver)/1000)
+
+GST_DEBUG_CATEGORY (apedemux_debug);
+#define GST_CAT_DEFAULT (apedemux_debug)
+
+static GstElementDetails gst_ape_demux_details =
+GST_ELEMENT_DETAILS ("APE tag demuxer",
+ "Codec/Demuxer/Metadata",
+ "Read and output APE tags while demuxing the contents",
+ "Ronald Bultje <rbultje@ronald.bitfreak.net>, "
+ "Tim-Philipp Müller <tim centricular net>");
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("application/x-apetag")
+ );
+
+static gboolean gst_ape_demux_identify_tag (GstTagDemux * demux,
+ GstBuffer * buffer, gboolean start_tag, guint * tag_size);
+static GstTagDemuxResult gst_ape_demux_parse_tag (GstTagDemux * demux,
+ GstBuffer * buffer, gboolean start_tag, guint * tag_size,
+ GstTagList ** tags);
+
+GST_BOILERPLATE (GstApeDemux, gst_ape_demux, GstTagDemux, GST_TYPE_TAG_DEMUX)
+
+ static void gst_ape_demux_base_init (gpointer klass)
+{
+ GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+
+ gst_element_class_add_pad_template (element_class,
+ gst_static_pad_template_get (&sink_factory));
+
+ gst_element_class_set_details (element_class, &gst_ape_demux_details);
+
+ GST_DEBUG_CATEGORY_INIT (apedemux_debug, "apedemux", 0,
+ "GStreamer APE tag demuxer");
+}
+
+static void
+gst_ape_demux_class_init (GstApeDemuxClass * klass)
+{
+ GstTagDemuxClass *tagdemux_class;
+
+ tagdemux_class = GST_TAG_DEMUX_CLASS (klass);
+
+ tagdemux_class->identify_tag = GST_DEBUG_FUNCPTR (gst_ape_demux_identify_tag);
+ tagdemux_class->parse_tag = GST_DEBUG_FUNCPTR (gst_ape_demux_parse_tag);
+}
+
+static void
+gst_ape_demux_init (GstApeDemux * apedemux, GstApeDemuxClass * gclass)
+{
+ GstTagDemux *tagdemux = GST_TAG_DEMUX (apedemux);
+
+ tagdemux->min_start_size = 32;
+ tagdemux->min_end_size = 32;
+
+ tagdemux->prefer_start_tag = TRUE;
+}
+
+static const struct _GstApeDemuxTagTableEntry
+{
+ const gchar *ape_tag;
+ const gchar *gst_tag;
+} tag_table[] = {
+ {
+ "replaygain_track_gain", GST_TAG_TRACK_GAIN}, {
+ "replaygain_track_peak", GST_TAG_TRACK_PEAK}, {
+ "replaygain_album_gain", GST_TAG_ALBUM_GAIN}, {
+ "replaygain_album_peak", GST_TAG_ALBUM_PEAK}, {
+ "title", GST_TAG_TITLE}, {
+ "artist", GST_TAG_ARTIST}, {
+ "album", GST_TAG_ALBUM}, {
+ "comment", GST_TAG_COMMENT}, {
+ "comments", GST_TAG_COMMENT}, {
+ "copyright", GST_TAG_COPYRIGHT}, {
+ "genre", GST_TAG_GENRE}, {
+ "isrc", GST_TAG_ISRC}, {
+ "track", GST_TAG_TRACK_NUMBER}, {
+ "year", GST_TAG_DATE}
+};
+
+static gboolean
+ape_demux_get_gst_tag_from_tag (const gchar * ape_tag,
+ const gchar ** gst_tag, GType * gst_tag_type)
+{
+ gint i;
+
+ for (i = 0; i < G_N_ELEMENTS (tag_table); ++i) {
+ if (g_ascii_strcasecmp (tag_table[i].ape_tag, ape_tag) == 0) {
+ *gst_tag = tag_table[i].gst_tag;
+ *gst_tag_type = gst_tag_get_type (tag_table[i].gst_tag);
+ return TRUE;
+ }
+ }
+
+ GST_WARNING ("Could not map APE tag '%s' to a GStreamer tag", ape_tag);
+ return FALSE;
+}
+
+static GstTagList *
+ape_demux_parse_tags (const guint8 * data, gint size)
+{
+ GstTagList *taglist = gst_tag_list_new ();
+ gboolean have_tag = FALSE;
+
+ GST_LOG ("Reading tags from chunk of size %u bytes", size);
+
+ /* get rid of header/footer */
+ if (size >= 32 && memcmp (data, "APETAGEX", 8) == 0) {
+ data += 32;
+ size -= 32;
+ }
+ if (size > 32 && memcmp (data + size - 32, "APETAGEX", 8) == 0) {
+ size -= 32;
+ }
+
+ /* read actual tags - at least 10 bytes for tag header */
+ while (size >= 10) {
+ guint len, n = 8;
+ gchar *tag, *val;
+ const gchar *gst_tag;
+ GType gst_tag_type;
+
+ /* find tag type and size */
+ len = GST_READ_UINT32_LE (data);
+ while (n < size && data[n] != 0x0)
+ n++;
+ if (n == size)
+ break;
+ g_assert (data[n] == 0x0);
+ n++;
+ if (size - n < len)
+ break;
+
+ /* read */
+ tag = g_strndup ((gchar *) data + 8, n - 9);
+ val = g_strndup ((gchar *) data + n, len);
+
+ if (ape_demux_get_gst_tag_from_tag (tag, &gst_tag, &gst_tag_type)) {
+ GValue v = { 0, };
+
+ switch (gst_tag_type) {
+ case G_TYPE_INT:
+ g_value_init (&v, G_TYPE_INT);
+ g_value_set_int (&v, atoi (val));
+ break;
+ case G_TYPE_UINT:
+ g_value_init (&v, G_TYPE_UINT);
+ g_value_set_uint (&v, (guint) atof (val)); /* hmmm */
+ break;
+ case G_TYPE_STRING:
+ g_value_init (&v, G_TYPE_STRING);
+ g_value_set_string (&v, val);
+ break;
+ case G_TYPE_DOUBLE:
+ g_value_init (&v, G_TYPE_DOUBLE);
+ g_value_set_double (&v, atof (val));
+ break;
+ default:{
+ if (gst_tag_type == GST_TYPE_DATE) {
+ GDate *date = g_date_new_dmy (1, 1, atoi (val));
+
+ g_value_init (&v, GST_TYPE_DATE);
+ gst_value_set_date (&v, date);
+ g_date_free (date);
+ } else {
+ GST_WARNING ("Unhandled tag type '%s' for tag '%s'",
+ g_type_name (gst_tag_type), gst_tag);
+ }
+ break;
+ }
+ }
+ if (G_VALUE_TYPE (&v) != 0) {
+ gst_tag_list_add_values (taglist, GST_TAG_MERGE_APPEND,
+ gst_tag, &v, NULL);
+ g_value_unset (&v);
+ have_tag = TRUE;
+ }
+ }
+ GST_DEBUG ("Read tag %s: %s", tag, val);
+ g_free (tag);
+ g_free (val);
+
+ /* move data pointer */
+ size -= len + n;
+ data += len + n;
+ }
+
+ GST_DEBUG ("Taglist: %" GST_PTR_FORMAT, taglist);
+ return taglist;
+}
+
+static gboolean
+gst_ape_demux_identify_tag (GstTagDemux * demux, GstBuffer * buffer,
+ gboolean start_tag, guint * tag_size)
+{
+ if (memcmp (GST_BUFFER_DATA (buffer), "APETAGEX", 8) != 0) {
+ GST_DEBUG_OBJECT (demux, "No APETAGEX marker at %s - not an APE file",
+ (start_tag) ? "start" : "end");
+ return FALSE;
+ }
+
+ *tag_size = GST_READ_UINT32_LE (GST_BUFFER_DATA (buffer) + 12);
+
+ /* size is without header, so add 32 to account for that */
+ *tag_size += 32;
+
+ return TRUE;
+}
+
+static GstTagDemuxResult
+gst_ape_demux_parse_tag (GstTagDemux * demux, GstBuffer * buffer,
+ gboolean start_tag, guint * tag_size, GstTagList ** tags)
+{
+ const guint8 *data;
+ const guint8 *footer;
+ gboolean have_header;
+ gboolean end_tag = !start_tag;
+ guint version, footer_size;
+
+ GST_LOG_OBJECT (demux, "Parsing buffer of size %u", GST_BUFFER_SIZE (buffer));
+
+ data = GST_BUFFER_DATA (buffer);
+ footer = GST_BUFFER_DATA (buffer) + GST_BUFFER_SIZE (buffer) - 32;
+
+ GST_LOG_OBJECT (demux, "Checking for footer at offset 0x%04x",
+ (guint) (footer - data));
+ if (footer > data && memcmp (footer, "APETAGEX", 8) == 0) {
+ GST_DEBUG_OBJECT (demux, "Found footer");
+ footer_size = 32;
+ } else {
+ GST_DEBUG_OBJECT (demux, "No footer");
+ footer_size = 0;
+ }
+
+ /* APE tags at the end must have a footer */
+ if (end_tag && footer_size == 0) {
+ GST_WARNING_OBJECT (demux, "Tag at end of file without footer!");
+ return GST_TAG_DEMUX_RESULT_BROKEN_TAG;
+ }
+
+ /* don't trust the header/footer flags, better detect them ourselves */
+ have_header = (memcmp (data, "APETAGEX", 8) == 0);
+
+ if (start_tag && !have_header) {
+ GST_DEBUG_OBJECT (demux, "Tag at beginning of file without header!");
+ return GST_TAG_DEMUX_RESULT_BROKEN_TAG;
+ }
+
+ if (end_tag && !have_header) {
+ GST_DEBUG_OBJECT (demux, "Tag at end of file has no header (APEv1)");
+ *tag_size -= 32; /* adjust tag size */
+ }
+
+ if (have_header) {
+ version = GST_READ_UINT32_LE (data + 8);
+ } else {
+ version = GST_READ_UINT32_LE (footer + 8);
+ }
+
+ /* skip header */
+ if (have_header) {
+ data += 32;
+ }
+
+ GST_DEBUG_OBJECT (demux, "APE tag with version %u, size %u at offset 0x%08"
+ G_GINT64_MODIFIER "x", version, *tag_size,
+ GST_BUFFER_OFFSET (buffer) + ((have_header) ? 0 : 32));
+
+ if (APE_VERSION_MAJOR (version) != 1 && APE_VERSION_MAJOR (version) != 2) {
+ GST_WARNING ("APE tag is version %u.%03u, but decoder only supports "
+ "v1 or v2. Ignoring.", APE_VERSION_MAJOR (version), version % 1000);
+ return GST_TAG_DEMUX_RESULT_OK;
+ }
+
+ *tags = ape_demux_parse_tags (data, *tag_size - footer_size);
+
+ return GST_TAG_DEMUX_RESULT_OK;
+}
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+ return gst_element_register (plugin, "apedemux",
+ GST_RANK_PRIMARY, GST_TYPE_APE_DEMUX);
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+ GST_VERSION_MINOR,
+ "apetag",
+ "APEv1/2 tag reader",
+ plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)
generated by cgit (git 2.34.1) at 2024-06-23 22:39:41 +0000