/* * RTP network protocol * Copyright (c) 2002 Fabrice Bellard * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * RTP protocol */ #include "libavutil/parseutils.h" #include "libavutil/avstring.h" #include "avformat.h" #include "avio_internal.h" #include "rtpdec.h" #include "url.h" #include <unistd.h> #include <stdarg.h> #include "internal.h" #include "network.h" #include "os_support.h" #include <fcntl.h> #if HAVE_POLL_H #include <sys/poll.h> #endif #include <sys/time.h> #define RTP_TX_BUF_SIZE (64 * 1024) #define RTP_RX_BUF_SIZE (128 * 1024) typedef struct RTPContext { URLContext *rtp_hd, *rtcp_hd; int rtp_fd, rtcp_fd; } RTPContext; /** * If no filename is given to av_open_input_file because you want to * get the local port first, then you must call this function to set * the remote server address. * * @param h media file context * @param uri of the remote server * @return zero if no error. */ int rtp_set_remote_url(URLContext *h, const char *uri) { RTPContext *s = h->priv_data; char hostname[256]; int port; char buf[1024]; char path[1024]; av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, path, sizeof(path), uri); ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port, "%s", path); ff_udp_set_remote_url(s->rtp_hd, buf); ff_url_join(buf, sizeof(buf), "udp", NULL, hostname, port + 1, "%s", path); ff_udp_set_remote_url(s->rtcp_hd, buf); return 0; } /** * add option to url of the form: * "http://host:port/path?option1=val1&option2=val2... */ static av_printf_format(3, 4) void url_add_option(char *buf, int buf_size, const char *fmt, ...) { char buf1[1024]; va_list ap; va_start(ap, fmt); if (strchr(buf, '?')) av_strlcat(buf, "&", buf_size); else av_strlcat(buf, "?", buf_size); vsnprintf(buf1, sizeof(buf1), fmt, ap); av_strlcat(buf, buf1, buf_size); va_end(ap); } static void build_udp_url(char *buf, int buf_size, const char *hostname, int port, int local_port, int ttl, int max_packet_size, int connect) { ff_url_join(buf, buf_size, "udp", NULL, hostname, port, NULL); if (local_port >= 0) url_add_option(buf, buf_size, "localport=%d", local_port); if (ttl >= 0) url_add_option(buf, buf_size, "ttl=%d", ttl); if (max_packet_size >=0) url_add_option(buf, buf_size, "pkt_size=%d", max_packet_size); if (connect) url_add_option(buf, buf_size, "connect=1"); } /** * url syntax: rtp://host:port[?option=val...] * option: 'ttl=n' : set the ttl value (for multicast only) * 'rtcpport=n' : set the remote rtcp port to n * 'localrtpport=n' : set the local rtp port to n * 'localrtcpport=n' : set the local rtcp port to n * 'pkt_size=n' : set max packet size * 'connect=0/1' : do a connect() on the UDP socket * deprecated option: * 'localport=n' : set the local port to n * * if rtcpport isn't set the rtcp port will be the rtp port + 1 * if local rtp port isn't set any available port will be used for the local * rtp and rtcp ports * if the local rtcp port is not set it will be the local rtp port + 1 */ static int rtp_open(URLContext *h, const char *uri, int flags) { RTPContext *s; int rtp_port, rtcp_port, ttl, connect, local_rtp_port, local_rtcp_port, max_packet_size; char hostname[256]; char buf[1024]; char path[1024]; const char *p; s = av_mallocz(sizeof(RTPContext)); if (!s) return AVERROR(ENOMEM); h->priv_data = s; av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &rtp_port, path, sizeof(path), uri); /* extract parameters */ ttl = -1; rtcp_port = rtp_port+1; local_rtp_port = -1; local_rtcp_port = -1; max_packet_size = -1; connect = 0; p = strchr(uri, '?'); if (p) { if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) { ttl = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "rtcpport", p)) { rtcp_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localport", p)) { local_rtp_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localrtpport", p)) { local_rtp_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "localrtcpport", p)) { local_rtcp_port = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) { max_packet_size = strtol(buf, NULL, 10); } if (av_find_info_tag(buf, sizeof(buf), "connect", p)) { connect = strtol(buf, NULL, 10); } } build_udp_url(buf, sizeof(buf), hostname, rtp_port, local_rtp_port, ttl, max_packet_size, connect); if (ffurl_open(&s->rtp_hd, buf, flags) < 0) goto fail; if (local_rtp_port>=0 && local_rtcp_port<0) local_rtcp_port = ff_udp_get_local_port(s->rtp_hd) + 1; build_udp_url(buf, sizeof(buf), hostname, rtcp_port, local_rtcp_port, ttl, max_packet_size, connect); if (ffurl_open(&s->rtcp_hd, buf, flags) < 0) goto fail; /* just to ease handle access. XXX: need to suppress direct handle access */ s->rtp_fd = ffurl_get_file_handle(s->rtp_hd); s->rtcp_fd = ffurl_get_file_handle(s->rtcp_hd); h->max_packet_size = s->rtp_hd->max_packet_size; h->is_streamed = 1; return 0; fail: if (s->rtp_hd) ffurl_close(s->rtp_hd); if (s->rtcp_hd) ffurl_close(s->rtcp_hd); av_free(s); return AVERROR(EIO); } static int rtp_read(URLContext *h, uint8_t *buf, int size) { RTPContext *s = h->priv_data; struct sockaddr_storage from; socklen_t from_len; int len, n; struct pollfd p[2] = {{s->rtp_fd, POLLIN, 0}, {s->rtcp_fd, POLLIN, 0}}; for(;;) { if (url_interrupt_cb()) return AVERROR_EXIT; /* build fdset to listen to RTP and RTCP packets */ n = poll(p, 2, 100); if (n > 0) { /* first try RTCP */ if (p[1].revents & POLLIN) { from_len = sizeof(from); len = recvfrom (s->rtcp_fd, buf, size, 0, (struct sockaddr *)&from, &from_len); if (len < 0) { if (ff_neterrno() == AVERROR(EAGAIN) || ff_neterrno() == AVERROR(EINTR)) continue; return AVERROR(EIO); } break; } /* then RTP */ if (p[0].revents & POLLIN) { from_len = sizeof(from); len = recvfrom (s->rtp_fd, buf, size, 0, (struct sockaddr *)&from, &from_len); if (len < 0) { if (ff_neterrno() == AVERROR(EAGAIN) || ff_neterrno() == AVERROR(EINTR)) continue; return AVERROR(EIO); } break; } } else if (n < 0) { if (ff_neterrno() == AVERROR(EINTR)) continue; return AVERROR(EIO); } } return len; } static int rtp_write(URLContext *h, const uint8_t *buf, int size) { RTPContext *s = h->priv_data; int ret; URLContext *hd; if (buf[1] >= RTCP_SR && buf[1] <= RTCP_APP) { /* RTCP payload type */ hd = s->rtcp_hd; } else { /* RTP payload type */ hd = s->rtp_hd; } ret = ffurl_write(hd, buf, size); return ret; } static int rtp_close(URLContext *h) { RTPContext *s = h->priv_data; ffurl_close(s->rtp_hd); ffurl_close(s->rtcp_hd); av_free(s); return 0; } /** * Return the local rtp port used by the RTP connection * @param h media file context * @return the local port number */ int rtp_get_local_rtp_port(URLContext *h) { RTPContext *s = h->priv_data; return ff_udp_get_local_port(s->rtp_hd); } /** * Return the local rtcp port used by the RTP connection * @param h media file context * @return the local port number */ int rtp_get_local_rtcp_port(URLContext *h) { RTPContext *s = h->priv_data; return ff_udp_get_local_port(s->rtcp_hd); } static int rtp_get_file_handle(URLContext *h) { RTPContext *s = h->priv_data; return s->rtp_fd; } int rtp_get_rtcp_file_handle(URLContext *h) { RTPContext *s = h->priv_data; return s->rtcp_fd; } URLProtocol ff_rtp_protocol = { .name = "rtp", .url_open = rtp_open, .url_read = rtp_read, .url_write = rtp_write, .url_close = rtp_close, .url_get_file_handle = rtp_get_file_handle, };