1 files changed, 97 insertions, 0 deletions
diff --git a/code/jasmine/udp-common.c b/code/jasmine/udp-common.c
new file mode 100755
index 00000000..c7314226
--- /dev/null
+++ b/code/jasmine/udp-common.c
@@ -0,0 +1,97 @@
+/*##############################################################################
+# Copyright (c) 2017 ZTE Coreporation and others.
+# hu.zhijiang@zte.com.cn
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Apache License, Version 2.0
+# which accompanies this distribution, and is available at
+# http://www.apache.org/licenses/LICENSE-2.0
+##############################################################################*/
+
+#include <fcntl.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+
+#include "buffer.h"
+#include "udp-common.h"
+#include "misc.h"
+
+struct mc_info mcinfo;
+
+int init_mcast_socket(struct in_addr *local_addr,
+                      struct sockaddr_in *maddr)
+{
+    struct ip_mreqn mreqn;  /* multicast request new */
+    int ms;  /* multicast socket */
+    u_short msock_port;
+    struct sockaddr_in bind_addr;
+
+    int msock_reuse = MCAST_REUSE;
+    u_char msock_loop = MCAST_LOOP;
+    u_char msock_ttl = MCAST_TTL;
+
+    if ((ms = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
+        crit("socket() failed, error allocating multicast socket");
+    }
+
+    // In order to let client and server on same host to use same port
+    if (setsockopt(ms, SOL_SOCKET, SO_REUSEADDR,
+        &msock_reuse, sizeof(msock_reuse)) < 0) {
+        crit("setsockopt() failed, can't set reuse flag");
+    }
+
+    if (setsockopt(ms, IPPROTO_IP, IP_MULTICAST_TTL,
+        &msock_ttl,sizeof(msock_ttl)) < 0) {
+        crit("setsockopt() failed, can't set ttl value");
+    }
+
+    if (setsockopt(ms, IPPROTO_IP, IP_MULTICAST_LOOP,
+        &msock_loop, sizeof(msock_loop)) < 0) {
+        crit("setsockopt() failed, can't set multicast packet looping");
+    }
+
+    /* TODO: Do we neet non-block? */
+
+    log(4, "Using multicast address: %s:%d",
+        inet_ntoa(maddr->sin_addr), ntohs(maddr->sin_port));
+
+    mreqn.imr_multiaddr = maddr->sin_addr;
+    mreqn.imr_address = *local_addr;
+    mreqn.imr_ifindex = 0;
+
+    /* Interface and remote mcast address choosing */
+
+    /* This tell interface which has mreqn.imr_address to join
+       mreqn.imr_multiaddr group, it has nothing to do with socket, port, and
+       mreqn.imr_address. */
+    if (setsockopt(ms, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+        &mreqn, sizeof(mreqn)) < 0) {
+        crit("setsockopt() failed, %s can't join multicast group",
+             inet_ntoa(*local_addr));
+    }
+
+    /* local address choosing */
+
+    /* This tell kernel to use interface which has mreqn.imr_address as device
+       and mreqn.imr_address as source addr when sending any multicast through
+       socket. */
+    if (setsockopt(ms, IPPROTO_IP, IP_MULTICAST_IF,
+        &mreqn, sizeof(mreqn)) < 0) {
+        crit("setsockopt() failed to IP_MULTICAST_IF.\n");
+    }
+
+    /* Local port choosing, remote port is choosed when calling sendto()! */
+
+    /* This let us uses specific udp port number as source port when sending
+       any multicast datagrams. So ip in maddr is useless here and should be
+       INADDR_ANY, otherwise, bind will return Invalid argument. */
+    msock_port = ntohs(maddr->sin_port);
+    bind_addr = make_addr(0, msock_port);
+    if (bind(ms, (struct sockaddr *)&bind_addr, sizeof(bind_addr)) < 0) {
+        crit("bind() error, can't bind mcast port");
+    }
+
+    return ms;
+}