--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/sipdroid/net/RtpPacket.java Sat Jan 23 22:19:43 2010 +0100
@@ -0,0 +1,318 @@
+/*
+ * Copyright (C) 2009 The Sipdroid Open Source Project
+ * Copyright (C) 2005 Luca Veltri - University of Parma - Italy
+ *
+ * This file is part of Sipdroid (http://www.sipdroid.org)
+ *
+ * Sipdroid is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This source code 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this source code; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+package src.org.sipdroid.net;
+
+import org.zoolu.tools.Random;
+
+/**
+ * RtpPacket implements a RTP packet.
+ */
+public class RtpPacket {
+ /* RTP packet buffer containing both the RTP header and payload */
+ byte[] packet;
+
+ /* RTP packet length */
+ int packet_len;
+
+ /* RTP header length */
+ // int header_len;
+ /** Gets the RTP packet */
+ public byte[] getPacket() {
+ return packet;
+ }
+
+ /** Gets the RTP packet length */
+ public int getLength() {
+ return packet_len;
+ }
+
+ /** Gets the RTP header length */
+ public int getHeaderLength() {
+ if (packet_len >= 12)
+ return 12 + 4 * getCscrCount();
+ else
+ return packet_len; // broken packet
+ }
+
+ /** Gets the RTP header length */
+ public int getPayloadLength() {
+ if (packet_len >= 12)
+ return packet_len - getHeaderLength();
+ else
+ return 0; // broken packet
+ }
+
+ /** Sets the RTP payload length */
+ public void setPayloadLength(int len) {
+ packet_len = getHeaderLength() + len;
+ }
+
+ // version (V): 2 bits
+ // padding (P): 1 bit
+ // extension (X): 1 bit
+ // CSRC count (CC): 4 bits
+ // marker (M): 1 bit
+ // payload type (PT): 7 bits
+ // sequence number: 16 bits
+ // timestamp: 32 bits
+ // SSRC: 32 bits
+ // CSRC list: 0 to 15 items, 32 bits each
+
+ /** Gets the version (V) */
+ public int getVersion() {
+ if (packet_len >= 12)
+ return (packet[0] >> 6 & 0x03);
+ else
+ return 0; // broken packet
+ }
+
+ /** Sets the version (V) */
+ public void setVersion(int v) {
+ if (packet_len >= 12)
+ packet[0] = (byte) ((packet[0] & 0x3F) | ((v & 0x03) << 6));
+ }
+
+ /** Whether has padding (P) */
+ public boolean hasPadding() {
+ if (packet_len >= 12)
+ return getBit(packet[0], 5);
+ else
+ return false; // broken packet
+ }
+
+ /** Set padding (P) */
+ public void setPadding(boolean p) {
+ if (packet_len >= 12)
+ packet[0] = setBit(p, packet[0], 5);
+ }
+
+ /** Whether has extension (X) */
+ public boolean hasExtension() {
+ if (packet_len >= 12)
+ return getBit(packet[0], 4);
+ else
+ return false; // broken packet
+ }
+
+ /** Set extension (X) */
+ public void setExtension(boolean x) {
+ if (packet_len >= 12)
+ packet[0] = setBit(x, packet[0], 4);
+ }
+
+ /** Gets the CSCR count (CC) */
+ public int getCscrCount() {
+ if (packet_len >= 12)
+ return (packet[0] & 0x0F);
+ else
+ return 0; // broken packet
+ }
+
+ /** Whether has marker (M) */
+ public boolean hasMarker() {
+ if (packet_len >= 12)
+ return getBit(packet[1], 7);
+ else
+ return false; // broken packet
+ }
+
+ /** Set marker (M) */
+ public void setMarker(boolean m) {
+ if (packet_len >= 12)
+ packet[1] = setBit(m, packet[1], 7);
+ }
+
+ /** Gets the payload type (PT) */
+ public int getPayloadType() {
+ if (packet_len >= 12)
+ return (packet[1] & 0x7F);
+ else
+ return -1; // broken packet
+ }
+
+ /** Sets the payload type (PT) */
+ public void setPayloadType(int pt) {
+ if (packet_len >= 12)
+ packet[1] = (byte) ((packet[1] & 0x80) | (pt & 0x7F));
+ }
+
+ /** Gets the sequence number */
+ public int getSequenceNumber() {
+ if (packet_len >= 12)
+ return getInt(packet, 2, 4);
+ else
+ return 0; // broken packet
+ }
+
+ /** Sets the sequence number */
+ public void setSequenceNumber(int sn) {
+ if (packet_len >= 12)
+ setInt(sn, packet, 2, 4);
+ }
+
+ /** Gets the timestamp */
+ public long getTimestamp() {
+ if (packet_len >= 12)
+ return getLong(packet, 4, 8);
+ else
+ return 0; // broken packet
+ }
+
+ /** Sets the timestamp */
+ public void setTimestamp(long timestamp) {
+ if (packet_len >= 12)
+ setLong(timestamp, packet, 4, 8);
+ }
+
+ /** Gets the SSCR */
+ public long getSscr() {
+ if (packet_len >= 12)
+ return getLong(packet, 8, 12);
+ else
+ return 0; // broken packet
+ }
+
+ /** Sets the SSCR */
+ public void setSscr(long ssrc) {
+ if (packet_len >= 12)
+ setLong(ssrc, packet, 8, 12);
+ }
+
+ /** Gets the CSCR list */
+ public long[] getCscrList() {
+ int cc = getCscrCount();
+ long[] cscr = new long[cc];
+ for (int i = 0; i < cc; i++)
+ cscr[i] = getLong(packet, 12 + 4 * i, 16 + 4 * i);
+ return cscr;
+ }
+
+ /** Sets the CSCR list */
+ public void setCscrList(long[] cscr) {
+ if (packet_len >= 12) {
+ int cc = cscr.length;
+ if (cc > 15)
+ cc = 15;
+ packet[0] = (byte) (((packet[0] >> 4) << 4) + cc);
+ cscr = new long[cc];
+ for (int i = 0; i < cc; i++)
+ setLong(cscr[i], packet, 12 + 4 * i, 16 + 4 * i);
+ // header_len=12+4*cc;
+ }
+ }
+
+ /** Sets the payload */
+ public void setPayload(byte[] payload, int len) {
+ if (packet_len >= 12) {
+ int header_len = getHeaderLength();
+ for (int i = 0; i < len; i++)
+ packet[header_len + i] = payload[i];
+ packet_len = header_len + len;
+ }
+ }
+
+ /** Gets the payload */
+ public byte[] getPayload() {
+ int header_len = getHeaderLength();
+ int len = packet_len - header_len;
+ byte[] payload = new byte[len];
+ for (int i = 0; i < len; i++)
+ payload[i] = packet[header_len + i];
+ return payload;
+ }
+
+ /** Creates a new RTP packet */
+ public RtpPacket(byte[] buffer, int packet_length) {
+ packet = buffer;
+ packet_len = packet_length;
+ if (packet_len < 12)
+ packet_len = 12;
+ init(0x0F);
+ }
+
+ /** init the RTP packet header (only PT) */
+ public void init(int ptype) {
+ init(ptype, Random.nextLong());
+ }
+
+ /** init the RTP packet header (PT and SSCR) */
+ public void init(int ptype, long sscr) {
+ init(ptype, Random.nextInt(), Random.nextLong(), sscr);
+ }
+
+ /** init the RTP packet header (PT, SQN, TimeStamp, SSCR) */
+ public void init(int ptype, int seqn, long timestamp, long sscr) {
+ setVersion(2);
+ setPayloadType(ptype);
+ setSequenceNumber(seqn);
+ setTimestamp(timestamp);
+ setSscr(sscr);
+ }
+
+ // *********************** Private and Static ***********************
+
+ /** Gets int value */
+ private static int getInt(byte b) {
+ return ((int) b + 256) % 256;
+ }
+
+ /** Gets long value */
+ private static long getLong(byte[] data, int begin, int end) {
+ long n = 0;
+ for (; begin < end; begin++) {
+ n <<= 8;
+ n += data[begin];
+ }
+ return n;
+ }
+
+ /** Sets long value */
+ private static void setLong(long n, byte[] data, int begin, int end) {
+ for (end--; end >= begin; end--) {
+ data[end] = (byte) (n % 256);
+ n >>= 8;
+ }
+ }
+
+ /** Gets Int value */
+ private static int getInt(byte[] data, int begin, int end) {
+ return (int) getLong(data, begin, end);
+ }
+
+ /** Sets Int value */
+ private static void setInt(int n, byte[] data, int begin, int end) {
+ setLong(n, data, begin, end);
+ }
+
+ /** Gets bit value */
+ private static boolean getBit(byte b, int bit) {
+ return (b >> bit) == 1;
+ }
+
+ /** Sets bit value */
+ private static byte setBit(boolean value, byte b, int bit) {
+ if (value)
+ return (byte) (b | (1 << bit));
+ else
+ return (byte) ((b | (1 << bit)) ^ (1 << bit));
+ }
+}