dtmf: convert to bit accessors

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/949>

gst/dtmf/gstdtmfcommon.h

@@ -34,19 +34,9 @@
 
 typedef struct
 {
-  unsigned event:8;             /* Current DTMF event */
+  guint8 event;             /* Current DTMF event */
-#if G_BYTE_ORDER == G_LITTLE_ENDIAN
+  guint8 volume;            /* power level of the tone, in dBm0 */
-  unsigned volume:6;            /* power level of the tone, in dBm0 */
+  guint16 duration;         /* Duration of digit, in timestamp units */
-  unsigned r:1;                 /* Reserved-bit */
-  unsigned e:1;                 /* End-bit */
-#elif G_BYTE_ORDER == G_BIG_ENDIAN
-  unsigned e:1;                 /* End-bit */
-  unsigned r:1;                 /* Reserved-bit */
-  unsigned volume:6;            /* power level of the tone, in dBm0 */
-#else
-#error "G_BYTE_ORDER should be big or little endian."
-#endif
-  unsigned duration:16;         /* Duration of digit, in timestamp units */
 } GstRTPDTMFPayload;
 
 #endif /* __GST_RTP_DTMF_COMMON_H__ */

gst/dtmf/gstrtpdtmfdepay.c

@@ -54,6 +54,7 @@
 #include <math.h>
 
 #include <gst/audio/audio.h>
+#include <gst/base/gstbitreader.h>
 #include <gst/rtp/gstrtpbuffer.h>
 
 #define DEFAULT_PACKET_INTERVAL  50     /* ms */
@@ -357,7 +358,7 @@ gst_rtp_dtmf_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
 
   GstRtpDTMFDepay *rtpdtmfdepay = NULL;
   GstBuffer *outbuf = NULL;
-  gint payload_len;
+  guint payload_len;
   guint8 *payload = NULL;
   guint32 timestamp;
   GstRTPDTMFPayload dtmf_payload;
@@ -365,6 +366,7 @@ gst_rtp_dtmf_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
   GstStructure *structure = NULL;
   GstMessage *dtmf_message = NULL;
   GstRTPBuffer rtpbuffer = GST_RTP_BUFFER_INIT;
+  GstBitReader bitreader;
 
   rtpdtmfdepay = GST_RTP_DTMF_DEPAY (depayload);
 
@@ -373,10 +375,14 @@ gst_rtp_dtmf_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
   payload_len = gst_rtp_buffer_get_payload_len (&rtpbuffer);
   payload = gst_rtp_buffer_get_payload (&rtpbuffer);
 
-  if (payload_len != sizeof (GstRTPDTMFPayload))
+  if (payload_len != 4)
     goto bad_packet;
 
-  memcpy (&dtmf_payload, payload, sizeof (GstRTPDTMFPayload));
+  gst_bit_reader_init (&bitreader, payload, payload_len);
+  gst_bit_reader_get_bits_uint8 (&bitreader, &dtmf_payload.event, 8);
+  gst_bit_reader_skip (&bitreader, 2);
+  gst_bit_reader_get_bits_uint8 (&bitreader, &dtmf_payload.volume, 6);
+  gst_bit_reader_get_bits_uint16 (&bitreader, &dtmf_payload.duration, 16);
 
   if (dtmf_payload.event > MAX_EVENT)
     goto bad_packet;
@@ -385,8 +391,6 @@ gst_rtp_dtmf_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
 
   timestamp = gst_rtp_buffer_get_timestamp (&rtpbuffer);
 
-  dtmf_payload.duration = g_ntohs (dtmf_payload.duration);
-
   /* clip to whole units of unit_time */
   if (rtpdtmfdepay->unit_time) {
     guint unit_time_clock =

gst/dtmf/gstrtpdtmfsrc.c

@@ -85,6 +85,7 @@
 #include <glib.h>
 
 #include "gstrtpdtmfsrc.h"
+#include <gst/base/gstbitwriter.h>
 
 #define GST_RTP_DTMF_TYPE_EVENT  1
 #define DEFAULT_PTIME            40     /* ms */
@@ -537,8 +538,6 @@ gst_rtp_dtmf_prepare_rtp_headers (GstRTPDTMFSrc * dtmfsrc,
   /* Only the very first packet gets a marker */
   if (dtmfsrc->first_packet) {
     gst_rtp_buffer_set_marker (rtpbuf, TRUE);
-  } else if (dtmfsrc->last_packet) {
-    dtmfsrc->payload->e = 1;
   }
 
   dtmfsrc->seqnum++;
@@ -552,10 +551,12 @@ static GstBuffer *
 gst_rtp_dtmf_src_create_next_rtp_packet (GstRTPDTMFSrc * dtmfsrc)
 {
   GstBuffer *buf;
-  GstRTPDTMFPayload *payload;
   GstRTPBuffer rtpbuffer = GST_RTP_BUFFER_INIT;
+  GstBitWriter bitwriter;
+  guint8 *payload;
+  guint8 end = dtmfsrc->last_packet ? 0x02 : 0;
 
-  buf = gst_rtp_buffer_new_allocate (sizeof (GstRTPDTMFPayload), 0, 0);
+  buf = gst_rtp_buffer_new_allocate (4, 0, 0);
 
   gst_rtp_buffer_map (buf, GST_MAP_READWRITE, &rtpbuffer);
 
@@ -569,12 +570,14 @@ gst_rtp_dtmf_src_create_next_rtp_packet (GstRTPDTMFSrc * dtmfsrc)
     GST_BUFFER_DURATION (buf) = dtmfsrc->ptime * GST_MSECOND;
   GST_BUFFER_PTS (buf) = dtmfsrc->timestamp;
 
-  payload = (GstRTPDTMFPayload *) gst_rtp_buffer_get_payload (&rtpbuffer);
+  payload = gst_rtp_buffer_get_payload (&rtpbuffer);
 
-  /* copy payload and convert to network-byte order */
+  memset (payload, 0, 4);
-  memmove (payload, dtmfsrc->payload, sizeof (GstRTPDTMFPayload));
+  gst_bit_writer_init_with_data (&bitwriter, payload, 4, FALSE);
-
+  gst_bit_writer_put_bits_uint8 (&bitwriter, dtmfsrc->payload->event, 8);
-  payload->duration = g_htons (payload->duration);
+  gst_bit_writer_put_bits_uint8 (&bitwriter, end, 2);
+  gst_bit_writer_put_bits_uint8 (&bitwriter, dtmfsrc->payload->volume, 6);
+  gst_bit_writer_put_bits_uint16 (&bitwriter, dtmfsrc->payload->duration, 16);
 
   if (dtmfsrc->redundancy_count <= 1 && dtmfsrc->last_packet) {
     GstClockTime inter_digit_interval = MIN_INTER_DIGIT_INTERVAL;