--- /dev/null
+/* GStreamer
+ * Copyright (C) <2021> Matthew Waters <matthew@centricular.com>
+ *
+ * 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-rtphdrextmid
+ * @title: rtphdrextmid
+ * @short_description: RTP Bundle Media Identification (MID) RTP Header
+ * Extension (RFC8843)
+ * @see_also: #GstRTPHeaderExtension, #GstRTPBasePayload, #GstRTPBaseDepayload, gstrtpbuffer
+ *
+ * Since: 1.22
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/rtp/gstrtpbuffer.h>
+
+#include "gstrtphdrext-mid.h"
+
+GST_DEBUG_CATEGORY_STATIC (rtphdrext_mid_debug);
+#define GST_CAT_DEFAULT (rtphdrext_mid_debug)
+
+#define MID_EXTMAP_STR GST_RTP_HDREXT_BASE "sdes:mid"
+
+enum
+{
+ PROP_0,
+ PROP_MID,
+};
+
+struct _GstRTPHeaderExtensionMid
+{
+ GstRTPHeaderExtension parent;
+
+ char *mid;
+};
+
+#define parent_class gst_rtp_header_extension_mid_parent_class
+G_DEFINE_TYPE_WITH_CODE (GstRTPHeaderExtensionMid,
+ gst_rtp_header_extension_mid, GST_TYPE_RTP_HEADER_EXTENSION,
+ GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "rtphdrext-mid", 0,
+ "RTP BUNDLE MID Header Extensions (RFC8843)")
+ );
+GST_ELEMENT_REGISTER_DEFINE (rtphdrextmid, "rtphdrextmid",
+ GST_RANK_MARGINAL, GST_TYPE_RTP_HEADER_EXTENSION_MID);
+
+static GstRTPHeaderExtensionFlags
+gst_rtp_header_extension_mid_get_supported_flags (GstRTPHeaderExtension * ext)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (ext);
+ GstRTPHeaderExtensionFlags flags =
+ GST_RTP_HEADER_EXTENSION_ONE_BYTE | GST_RTP_HEADER_EXTENSION_TWO_BYTE;
+ gssize mid_len = -1;
+
+ GST_OBJECT_LOCK (ext);
+ if (self->mid)
+ mid_len = strlen (self->mid);
+ GST_OBJECT_UNLOCK (ext);
+ if (mid_len > 16)
+ flags = GST_RTP_HEADER_EXTENSION_TWO_BYTE;
+
+ return flags;
+}
+
+static gsize
+gst_rtp_header_extension_mid_get_max_size (GstRTPHeaderExtension * ext,
+ const GstBuffer * buffer)
+{
+ if (gst_rtp_header_extension_mid_get_supported_flags (ext) &
+ GST_RTP_HEADER_EXTENSION_ONE_BYTE)
+ return 16;
+ else
+ return 255;
+}
+
+static gssize
+gst_rtp_header_extension_mid_write (GstRTPHeaderExtension * ext,
+ const GstBuffer * input_meta, GstRTPHeaderExtensionFlags write_flags,
+ GstBuffer * output, guint8 * data, gsize size)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (ext);
+ gsize len = 0;
+
+ g_return_val_if_fail (size >=
+ gst_rtp_header_extension_mid_get_max_size (ext, NULL), -1);
+ g_return_val_if_fail (write_flags &
+ gst_rtp_header_extension_mid_get_supported_flags (ext), -1);
+
+ GST_OBJECT_LOCK (ext);
+ if (!self->mid) {
+ GST_LOG_OBJECT (self, "no mid to write");
+ goto out;
+ }
+
+ /* TODO: we don't need to always add mid, we can selectively omit it from e.g.
+ * non-video-keyframes or some percentage of the produced frames, e.g. RFC8843
+ * mentions possibly using packet-loss as a indication of how often to add mid
+ * to packets */
+ len = strlen (self->mid);
+ if ((write_flags & GST_RTP_HEADER_EXTENSION_TWO_BYTE) == 0 && len > 16) {
+ GST_DEBUG_OBJECT (self, "cannot write a mid of size %" G_GSIZE_FORMAT
+ " without using the two byte extension format", len);
+ len = 0;
+ goto out;
+ }
+ if (len > 0) {
+ GST_LOG_OBJECT (self, "writing mid \'%s\'", self->mid);
+ memcpy (data, self->mid, len);
+ }
+
+out:
+ GST_OBJECT_UNLOCK (ext);
+ return len;
+}
+
+static gboolean
+gst_rtp_header_extension_mid_read (GstRTPHeaderExtension * ext,
+ GstRTPHeaderExtensionFlags read_flags, const guint8 * data, gsize size,
+ GstBuffer * buffer)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (ext);
+ gboolean notify = FALSE;
+
+ if (!data || size == 0)
+ return TRUE;
+
+ if (read_flags & GST_RTP_HEADER_EXTENSION_ONE_BYTE && (size < 1 || size > 16)) {
+ GST_ERROR_OBJECT (ext,
+ "one-byte header extensions must be between 1 and 16 bytes inculusive");
+ return FALSE;
+ }
+
+ GST_OBJECT_LOCK (self);
+ if (!self->mid || strncmp ((const char *) data, self->mid, size) != 0) {
+ g_clear_pointer (&self->mid, g_free);
+ self->mid = g_strndup ((const char *) data, size);
+ notify = TRUE;
+ }
+ GST_OBJECT_UNLOCK (self);
+
+ if (notify)
+ g_object_notify ((GObject *) self, "mid");
+
+ return TRUE;
+}
+
+static void
+gst_rtp_header_extension_mid_get_property (GObject * object,
+ guint prop_id, GValue * value, GParamSpec * pspec)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (object);
+
+ switch (prop_id) {
+ case PROP_MID:
+ GST_OBJECT_LOCK (self);
+ g_value_set_string (value, self->mid);
+ GST_OBJECT_UNLOCK (self);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static gboolean
+validate_mid (const char *rid)
+{
+ const char *iter;
+
+ /* For avoidance of doubt, the only allowed byte values for
+ * these IDs are decimal 48 through 57, 65 through 90, and 97 through
+ * 122.
+ */
+ for (iter = rid; iter && iter[0]; iter++) {
+ if (iter[0] < 48)
+ return FALSE;
+ if (iter[0] > 122)
+ return FALSE;
+ if (iter[0] > 57 && iter[0] < 65)
+ return FALSE;
+ if (iter[0] > 90 && iter[0] < 97)
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static void
+gst_rtp_header_extension_mid_set_property (GObject * object,
+ guint prop_id, const GValue * value, GParamSpec * pspec)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (object);
+
+ switch (prop_id) {
+ case PROP_MID:{
+ const char *mid;
+ GST_OBJECT_LOCK (self);
+ mid = g_value_get_string (value);
+ if (!validate_mid (mid)) {
+ GST_WARNING_OBJECT (self, "Could not set mid \'%s\'. Validation failed",
+ mid);
+ } else {
+ g_clear_pointer (&self->mid, g_free);
+ self->mid = g_strdup (mid);
+ }
+ GST_OBJECT_UNLOCK (self);
+ break;
+ }
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_rtp_header_extension_mid_finalize (GObject * object)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (object);
+
+ g_clear_pointer (&self->mid, g_free);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static gboolean
+gst_rtp_header_extension_mid_set_caps_from_attributes (GstRTPHeaderExtension
+ * ext, GstCaps * caps)
+{
+ GstRTPHeaderExtensionMid *self = GST_RTP_HEADER_EXTENSION_MID (ext);
+ GstStructure *s = gst_caps_get_structure (caps, 0);
+
+ if (!GST_RTP_HEADER_EXTENSION_CLASS (parent_class)->set_caps_from_attributes
+ (ext, caps))
+ return FALSE;
+
+ GST_OBJECT_LOCK (ext);
+ if (self->mid) {
+ if (gst_structure_has_field (s, "a-mid")) {
+ GST_WARNING_OBJECT (ext, "caps already contain the \'a-mid\' field!");
+ goto error;
+ }
+ gst_structure_set (s, "a-mid", G_TYPE_STRING, self->mid, NULL);
+ GST_DEBUG_OBJECT (ext, "set mid \'%s\' on output caps", self->mid);
+ }
+ GST_OBJECT_UNLOCK (ext);
+
+ return TRUE;
+
+error:
+ GST_OBJECT_UNLOCK (ext);
+ return FALSE;
+}
+
+static void
+gst_rtp_header_extension_mid_class_init (GstRTPHeaderExtensionMidClass * klass)
+{
+ GstRTPHeaderExtensionClass *rtp_hdr_class;
+ GstElementClass *gstelement_class;
+ GObjectClass *gobject_class;
+
+ rtp_hdr_class = (GstRTPHeaderExtensionClass *) klass;
+ gobject_class = (GObjectClass *) klass;
+ gstelement_class = (GstElementClass *) klass;
+
+ gobject_class->set_property = gst_rtp_header_extension_mid_set_property;
+ gobject_class->get_property = gst_rtp_header_extension_mid_get_property;
+ gobject_class->finalize = gst_rtp_header_extension_mid_finalize;
+
+ /**
+ * rtphdrextmid:mid:
+ *
+ * The Media Identification (MID) value either last retrieved from the RTP
+ * Header extension, or to set on outgoing RTP packets.
+ *
+ * Since: 1.22
+ */
+ g_object_class_install_property (gobject_class, PROP_MID,
+ g_param_spec_string ("mid", "mid",
+ "The Media Identification (MID) value last read or to write from/to "
+ "RTP buffers", NULL, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ rtp_hdr_class->get_supported_flags =
+ gst_rtp_header_extension_mid_get_supported_flags;
+ rtp_hdr_class->get_max_size = gst_rtp_header_extension_mid_get_max_size;
+ rtp_hdr_class->write = gst_rtp_header_extension_mid_write;
+ rtp_hdr_class->read = gst_rtp_header_extension_mid_read;
+ rtp_hdr_class->set_caps_from_attributes =
+ gst_rtp_header_extension_mid_set_caps_from_attributes;
+
+ gst_element_class_set_static_metadata (gstelement_class,
+ "RTP BUNDLE MID Header Extension", GST_RTP_HDREXT_ELEMENT_CLASS,
+ "Extends RTP packets to add or retrieve a Media Identification (MID) "
+ "value as specified in RFC8843",
+ "Matthew Waters <matthew@centricular.com>");
+ gst_rtp_header_extension_class_set_uri (rtp_hdr_class, MID_EXTMAP_STR);
+}
+
+static void
+gst_rtp_header_extension_mid_init (GstRTPHeaderExtensionMid * self)
+{
+}
projects / platform / upstream / gstreamer.git / commitdiff