add an RTP sender module

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@712 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/modules/rtp/sap.c

@@ -0,0 +1,107 @@
+/* $Id$ */
+
+/***
+  This file is part of polypaudio.
+ 
+  polypaudio 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 of the License,
+  or (at your option) any later version.
+ 
+  polypaudio 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 Lesser General Public License
+  along with polypaudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+#include <time.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <polypcore/util.h>
+#include <polypcore/log.h>
+#include <polypcore/xmalloc.h>
+
+#include "sap.h"
+
+pa_sap_context* pa_sap_context_init_send(pa_sap_context *c, int fd, char *sdp_data) {
+    assert(c);
+    assert(fd >= 0);
+    assert(sdp_data);
+
+    c->fd = fd;
+    c->sdp_data = sdp_data;
+    c->msg_id_hash = (uint16_t) (rand()*rand());
+    
+    return c;    
+}
+
+void pa_sap_context_destroy(pa_sap_context *c) {
+    assert(c);
+
+    close(c->fd);
+    pa_xfree(c->sdp_data);
+}
+
+int pa_sap_send(pa_sap_context *c, int goodbye) {
+    uint32_t header;
+    const char mime[] = "application/sdp";
+    struct sockaddr_storage sa_buf;
+    struct sockaddr *sa = (struct sockaddr*) &sa_buf;
+    socklen_t salen = sizeof(sa_buf);
+    struct iovec iov[4];
+    struct msghdr m;
+    int k;
+
+    if (getsockname(c->fd, sa, &salen) < 0) {
+        pa_log("getsockname() failed: %s\n", strerror(errno));
+        return -1;
+    }
+
+    assert(sa->sa_family == AF_INET || sa->sa_family == AF_INET6);
+    
+    header = htonl(((uint32_t) 1 << 29) |
+                   (sa->sa_family == AF_INET6 ? (uint32_t) 1 << 28 : 0) |
+                   (goodbye ? (uint32_t) 1 << 26 : 0) |
+                   (c->msg_id_hash));
+
+    iov[0].iov_base = &header;
+    iov[0].iov_len = sizeof(header);
+
+    iov[1].iov_base = sa->sa_family == AF_INET ? (void*) &((struct sockaddr_in*) sa)->sin_addr : (void*) &((struct sockaddr_in6*) sa)->sin6_addr;
+    iov[1].iov_len = sa->sa_family == AF_INET ? 4 : 16;
+
+    iov[2].iov_base = (char*) mime;
+    iov[2].iov_len = sizeof(mime);
+
+    iov[3].iov_base = c->sdp_data;
+    iov[3].iov_len = strlen(c->sdp_data);
+                   
+    m.msg_name = NULL;
+    m.msg_namelen = 0;
+    m.msg_iov = iov;
+    m.msg_iovlen = 4;
+    m.msg_control = NULL;
+    m.msg_controllen = 0;
+    m.msg_flags = 0;
+    
+    if ((k = sendmsg(c->fd, &m, MSG_DONTWAIT)) < 0)
+        pa_log("sendmsg() failed: %s\n", strerror(errno));
+
+    return k;
+}