Multicast socket API

net/udp/udp_socket_libevent.cc

Index: net/udp/udp_socket_libevent.cc
diff --git a/net/udp/udp_socket_libevent.cc b/net/udp/udp_socket_libevent.cc
index 063da08c387963b60066b3d1459aa82b9703a970..91dec1ec10ef6f21efae6f34ddb309e5d65c565b 100644
--- a/net/udp/udp_socket_libevent.cc
+++ b/net/udp/udp_socket_libevent.cc
@@ -41,7 +41,9 @@ UDPSocketLibevent::UDPSocketLibevent(
     net::NetLog* net_log,
     const net::NetLog::Source& source)
         : socket_(kInvalidSocket),
-          socket_options_(0),
+          addr_family_(0),
+          socket_options_(SOCKET_OPTION_MULTICAST_LOOP),
+          multicast_time_to_live_(1),
           bind_type_(bind_type),
           rand_int_cb_(rand_int_cb),
           read_watcher_(this),
@@ -363,7 +365,8 @@ void UDPSocketLibevent::LogRead(int result,
 }
 
 int UDPSocketLibevent::CreateSocket(const IPEndPoint& address) {
-  socket_ = socket(address.GetSockAddrFamily(), SOCK_DGRAM, 0);
+  addr_family_ = address.GetSockAddrFamily();
+  socket_ = socket(addr_family_, SOCK_DGRAM, 0);
   if (socket_ == kInvalidSocket)
     return MapSystemError(errno);
   if (SetNonBlocking(socket_)) {
@@ -476,11 +479,40 @@ int UDPSocketLibevent::SetSocketOptions() {
     // port.
     rv = setsockopt(socket_, SOL_SOCKET, SO_REUSEPORT, &true_value,
                     sizeof(true_value));
-    if (rv < 0)
-      return MapSystemError(errno);
-#endif  // defined(OS_MACOSX)
+#else
     rv = setsockopt(socket_, SOL_SOCKET, SO_BROADCAST, &true_value,
                     sizeof(true_value));
+#endif  // defined(OS_MACOSX)
+    if (rv < 0)
+      return MapSystemError(errno);
+  }
+
+  if (!(socket_options_ & SOCKET_OPTION_MULTICAST_LOOP)) {
+    int rv;
+    if (addr_family_ == AF_INET) {
+      u_char loop = 0;
+      rv = setsockopt(socket_, IPPROTO_IP, IP_MULTICAST_LOOP,
+                      &loop, sizeof(loop));
+    } else {
+      u_int loop = 0;
+      rv = setsockopt(socket_, IPPROTO_IPV6, IPV6_MULTICAST_LOOP,
+                      &loop, sizeof(loop));
+    }
+    if (rv < 0)
+      return MapSystemError(errno);
+  }
+  if (multicast_time_to_live_ != IP_DEFAULT_MULTICAST_TTL) {
+    int rv;
+    if (addr_family_ == AF_INET) {
+      u_char ttl = multicast_time_to_live_;
+      rv = setsockopt(socket_, IPPROTO_IP, IP_MULTICAST_TTL,
+                      &ttl, sizeof(ttl));
+    } else {
+      // Signed interger. -1 to use route default.
+      int ttl = multicast_time_to_live_;
+      rv = setsockopt(socket_, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
+                      &ttl, sizeof(ttl));
+    }
     if (rv < 0)
       return MapSystemError(errno);
   }
@@ -509,4 +541,99 @@ int UDPSocketLibevent::RandomBind(const IPEndPoint& address) {
   return DoBind(IPEndPoint(ip, 0));
 }
 
+int UDPSocketLibevent::JoinGroup(const IPAddressNumber& group_address) const {
+  DCHECK(CalledOnValidThread());
+  if(!is_connected())

[wtc, 2013/04/23 22:15:26]

Add a space between "if" and the opening parenthesis "(".
This is recommended by the Style Guide.

Make the same change to the other three if statements you
added, and also to udp_socket_win.cc.

[Bei Zhang, 2013/04/24 16:50:50]

Done.

+    return ERR_SOCKET_NOT_CONNECTED;
+
+  switch (group_address.size()) {
+    case kIPv4AddressSize: {
+      if (addr_family_ != AF_INET)
+        return ERR_ADDRESS_INVALID;
+      ip_mreq mreq;
+      mreq.imr_interface.s_addr = INADDR_ANY;
+      memcpy(&mreq.imr_multiaddr, &group_address[0], kIPv4AddressSize);
+      int rv = setsockopt(socket_, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+                          &mreq, sizeof(mreq));
+      if (rv < 0)
+        return MapSystemError(errno);
+      return OK;
+    }
+    case kIPv6AddressSize: {
+      if (addr_family_ != AF_INET6)
+        return ERR_ADDRESS_INVALID;
+      ipv6_mreq mreq;
+      mreq.ipv6mr_interface = 0;  // 0 indicates default multicast interface.
+      memcpy(&mreq.ipv6mr_multiaddr, &group_address[0], kIPv6AddressSize);
+      int rv = setsockopt(socket_, IPPROTO_IPV6, IPV6_JOIN_GROUP,
+                          &mreq, sizeof(mreq));
+      if (rv < 0)
+        return MapSystemError(errno);
+      return OK;
+    }
+    default:
+      NOTREACHED() << "Invalid address family";
+      return ERR_ADDRESS_INVALID;
+  }
+}
+
+int UDPSocketLibevent::LeaveGroup(const IPAddressNumber& group_address) const {
+  DCHECK(CalledOnValidThread());
+
+  if(!is_connected())
+    return ERR_SOCKET_NOT_CONNECTED;
+
+  switch (group_address.size()) {
+    case kIPv4AddressSize: {
+      if (addr_family_ != AF_INET)
+        return ERR_ADDRESS_INVALID;
+      ip_mreq mreq;
+      mreq.imr_interface.s_addr = INADDR_ANY;
+      memcpy(&mreq.imr_multiaddr, &group_address[0], kIPv4AddressSize);
+      int rv = setsockopt(socket_, IPPROTO_IP, IP_DROP_MEMBERSHIP,
+                          &mreq, sizeof(mreq));
+      if (rv < 0)
+        return MapSystemError(errno);
+      return OK;
+    }
+    case kIPv6AddressSize: {
+      if (addr_family_ != AF_INET6)
+        return ERR_ADDRESS_INVALID;
+      ipv6_mreq mreq;
+      mreq.ipv6mr_interface = 0;  // 0 indicates default multicast interface.
+      memcpy(&mreq.ipv6mr_multiaddr, &group_address[0], kIPv6AddressSize);
+      int rv = setsockopt(socket_, IPPROTO_IPV6, IPV6_LEAVE_GROUP,
+                          &mreq, sizeof(mreq));
+      if (rv < 0)
+        return MapSystemError(errno);
+      return OK;
+    }
+    default:
+      NOTREACHED() << "Invalid address family";
+      return ERR_ADDRESS_INVALID;
+  }
+}
+
+int UDPSocketLibevent::SetMulticastTimeToLive(int time_to_live) {
+  DCHECK(CalledOnValidThread());
+  if(is_connected())
+    return ERR_UNEXPECTED;

[wtc, 2013/04/23 22:15:26]

We should add a new error code ERR_SOCKET_IS_CONNECTED.
Let's do that in a separate CL.

[Bei Zhang, 2013/04/24 16:50:50]

Created a bug at http://crbug.com/235066 .

On 2013/04/23 22:15:26, wtc wrote:

+
+  if (time_to_live < 0 || time_to_live > 255)
+    return ERR_INVALID_ARGUMENT;
+  multicast_time_to_live_ = time_to_live;
+  return OK;
+}
+
+int UDPSocketLibevent::SetMulticastLoopbackMode(bool loopback) {
+  DCHECK(CalledOnValidThread());
+  if(is_connected())
+    return ERR_UNEXPECTED;
+
+  if (loopback)
+    socket_options_ |= SOCKET_OPTION_MULTICAST_LOOP;
+  else
+    socket_options_ &= ~SOCKET_OPTION_MULTICAST_LOOP;
+  return OK;
+}
 }  // namespace net