/* Imported from the dvbstream-0.2 project * * Modified for use with MPlayer, for details see the changelog at * http://svn.mplayerhq.hu/mplayer/trunk/ * $Id$ */ #include <stdlib.h> #include <string.h> #include <unistd.h> #include <stdlib.h> #include <stdio.h> #include <sys/types.h> #include <ctype.h> #include "config.h" #ifndef HAVE_WINSOCK2 #include <netinet/in.h> #include <sys/socket.h> #include <arpa/inet.h> #define closesocket close #else #include <winsock2.h> #include <ws2tcpip.h> #endif #include <errno.h> #include "stream.h" /* MPEG-2 TS RTP stack */ #define DEBUG 1 #include "mp_msg.h" #include "rtp.h" // RTP reorder routines // Also handling of repeated UDP packets (a bug of ExtremeNetworks switches firmware) // rtpreord procedures // write rtp packets in cache // get rtp packets reordered #define MAXRTPPACKETSIN 32 // The number of max packets being reordered struct rtpbits { unsigned int v:2; /* version: 2 */ unsigned int p:1; /* is there padding appended: 0 */ unsigned int x:1; /* number of extension headers: 0 */ unsigned int cc:4; /* number of CSRC identifiers: 0 */ unsigned int m:1; /* marker: 0 */ unsigned int pt:7; /* payload type: 33 for MPEG2 TS - RFC 1890 */ unsigned int sequence:16; /* sequence number: random */ }; struct rtpheader { /* in network byte order */ struct rtpbits b; int timestamp; /* start: random */ int ssrc; /* random */ }; struct rtpbuffer { unsigned char data[MAXRTPPACKETSIN][STREAM_BUFFER_SIZE]; unsigned short seq[MAXRTPPACKETSIN]; unsigned short len[MAXRTPPACKETSIN]; unsigned short first; }; static struct rtpbuffer rtpbuf; static int getrtp2(int fd, struct rtpheader *rh, char** data, int* lengthData); // RTP Reordering functions // Algorithm works as follows: // If next packet is in sequence just copy it to buffer // Otherwise copy it in cache according to its sequence number // Cache is a circular array where "rtpbuf.first" points to next sequence slot // and keeps track of expected sequence // Initialize rtp cache static void rtp_cache_reset(unsigned short seq) { int i; rtpbuf.first = 0; rtpbuf.seq[0] = ++seq; for (i=0; i<MAXRTPPACKETSIN; i++) { rtpbuf.len[i] = 0; } } // Write in a cache the rtp packet in right rtp sequence order static int rtp_cache(int fd, char *buffer, int length) { struct rtpheader rh; int newseq; char *data; unsigned short seq; static int is_first = 1; getrtp2(fd, &rh, &data, &length); if(!length) return 0; seq = rh.b.sequence; newseq = seq - rtpbuf.seq[rtpbuf.first]; if ((newseq == 0) || is_first) { is_first = 0; //mp_msg(MSGT_NETWORK, MSGL_DBG4, "RTP (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq); rtpbuf.first = ( 1 + rtpbuf.first ) % MAXRTPPACKETSIN; rtpbuf.seq[rtpbuf.first] = ++seq; goto feed; } if (newseq > MAXRTPPACKETSIN) { mp_msg(MSGT_NETWORK, MSGL_DBG2, "Overrun(seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq); rtp_cache_reset(seq); goto feed; } if (newseq < 0) { int i; // Is it a stray packet re-sent to network? for (i=0; i<MAXRTPPACKETSIN; i++) { if (rtpbuf.seq[i] == seq) { mp_msg(MSGT_NETWORK, MSGL_ERR, "Stray packet (seq[%d]=%d seq=%d, newseq=%d found at %d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq, i); return 0; // Yes, it is! } } // Some heuristic to decide when to drop packet or to restart everything if (newseq > -(3 * MAXRTPPACKETSIN)) { mp_msg(MSGT_NETWORK, MSGL_ERR, "Too Old packet (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq); return 0; // Yes, it is! } mp_msg(MSGT_NETWORK, MSGL_ERR, "Underrun(seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq); rtp_cache_reset(seq); goto feed; } mp_msg(MSGT_NETWORK, MSGL_DBG4, "Out of Seq (seq[%d]=%d seq=%d, newseq=%d)\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first], seq, newseq); newseq = ( newseq + rtpbuf.first ) % MAXRTPPACKETSIN; memcpy (rtpbuf.data[newseq], data, length); rtpbuf.len[newseq] = length; rtpbuf.seq[newseq] = seq; return 0; feed: memcpy (buffer, data, length); return length; } // Get next packet in cache // Look in cache to get first packet in sequence static int rtp_get_next(int fd, char *buffer, int length) { int i; unsigned short nextseq; // If we have empty buffer we loop to fill it for (i=0; i < MAXRTPPACKETSIN -3; i++) { if (rtpbuf.len[rtpbuf.first] != 0) break; length = rtp_cache(fd, buffer, length) ; // returns on first packet in sequence if (length > 0) { //mp_msg(MSGT_NETWORK, MSGL_DBG4, "Getting rtp [%d] %hu\n", i, rtpbuf.first); return length; } else if (length < 0) break; // Only if length == 0 loop continues! } i = rtpbuf.first; while (rtpbuf.len[i] == 0) { mp_msg(MSGT_NETWORK, MSGL_ERR, "Lost packet %hu\n", rtpbuf.seq[i]); i = ( 1 + i ) % MAXRTPPACKETSIN; if (rtpbuf.first == i) break; } rtpbuf.first = i; // Copy next non empty packet from cache mp_msg(MSGT_NETWORK, MSGL_DBG4, "Getting rtp from cache [%d] %hu\n", rtpbuf.first, rtpbuf.seq[rtpbuf.first]); memcpy (buffer, rtpbuf.data[rtpbuf.first], rtpbuf.len[rtpbuf.first]); length = rtpbuf.len[rtpbuf.first]; // can be zero? // Reset fisrt slot and go next in cache rtpbuf.len[rtpbuf.first] = 0; nextseq = rtpbuf.seq[rtpbuf.first]; rtpbuf.first = ( 1 + rtpbuf.first ) % MAXRTPPACKETSIN; rtpbuf.seq[rtpbuf.first] = nextseq + 1; return length; } // Read next rtp packet using cache int read_rtp_from_server(int fd, char *buffer, int length) { // Following test is ASSERT (i.e. uneuseful if code is correct) if(buffer==NULL || length<STREAM_BUFFER_SIZE) { mp_msg(MSGT_NETWORK, MSGL_ERR, "RTP buffer invalid; no data return from network\n"); return 0; } // loop just to skip empty packets while ((length = rtp_get_next(fd, buffer, length)) == 0) { mp_msg(MSGT_NETWORK, MSGL_ERR, "Got empty packet from RTP cache!?\n"); } return length; } static int getrtp2(int fd, struct rtpheader *rh, char** data, int* lengthData) { static char buf[1600]; unsigned int intP; char* charP = (char*) &intP; int headerSize; int lengthPacket; lengthPacket=recv(fd,buf,1590,0); if (lengthPacket<0) mp_msg(MSGT_NETWORK,MSGL_ERR,"rtp: socket read error\n"); else if (lengthPacket<12) mp_msg(MSGT_NETWORK,MSGL_ERR,"rtp: packet too small (%d) to be an rtp frame (>12bytes)\n", lengthPacket); if(lengthPacket<12) { *lengthData = 0; return 0; } rh->b.v = (unsigned int) ((buf[0]>>6)&0x03); rh->b.p = (unsigned int) ((buf[0]>>5)&0x01); rh->b.x = (unsigned int) ((buf[0]>>4)&0x01); rh->b.cc = (unsigned int) ((buf[0]>>0)&0x0f); rh->b.m = (unsigned int) ((buf[1]>>7)&0x01); rh->b.pt = (unsigned int) ((buf[1]>>0)&0x7f); intP = 0; memcpy(charP+2,&buf[2],2); rh->b.sequence = ntohl(intP); intP = 0; memcpy(charP,&buf[4],4); rh->timestamp = ntohl(intP); headerSize = 12 + 4*rh->b.cc; /* in bytes */ *lengthData = lengthPacket - headerSize; *data = (char*) buf + headerSize; // mp_msg(MSGT_NETWORK,MSGL_DBG2,"Reading rtp: v=%x p=%x x=%x cc=%x m=%x pt=%x seq=%x ts=%x lgth=%d\n",rh->b.v,rh->b.p,rh->b.x,rh->b.cc,rh->b.m,rh->b.pt,rh->b.sequence,rh->timestamp,lengthPacket); return 0; }