5 files changed, 13 insertions, 6 deletions
diff --git a/net/base/net_error_list.h b/net/base/net_error_list.h
index ff6e347..5afb522 100644
--- a/net/base/net_error_list.h
+++ b/net/base/net_error_list.h
@@ -91,6 +91,9 @@ NET_ERROR(NETWORK_CHANGED, -21)
 // administrator.
 NET_ERROR(BLOCKED_BY_ADMINISTRATOR, -22)
 
+// The socket is already connected.
+NET_ERROR(SOCKET_IS_CONNECTED, -23)
+
 // A connection was closed (corresponding to a TCP FIN).
 NET_ERROR(CONNECTION_CLOSED, -100)
 
diff --git a/net/base/net_errors_posix.cc b/net/base/net_errors_posix.cc
index 8e9c7d5..3491b11 100644
--- a/net/base/net_errors_posix.cc
+++ b/net/base/net_errors_posix.cc
@@ -51,6 +51,8 @@ Error MapSystemError(int os_error) {
       return ERR_MSG_TOO_BIG;
     case ENOTCONN:
       return ERR_SOCKET_NOT_CONNECTED;
+    case EISCONN:
+      return ERR_SOCKET_IS_CONNECTED;
     case EINVAL:
       return ERR_INVALID_ARGUMENT;
     case EADDRINUSE:
diff --git a/net/base/net_errors_win.cc b/net/base/net_errors_win.cc
index c56225f..2cde82f4d 100644
--- a/net/base/net_errors_win.cc
+++ b/net/base/net_errors_win.cc
@@ -37,6 +37,8 @@ Error MapSystemError(int os_error) {
     case WSA_IO_INCOMPLETE:
     case WSAEDISCON:
       return ERR_CONNECTION_CLOSED;
+    case WSAEISCONN:
+      return ERR_SOCKET_IS_CONNECTED;
     case WSAEHOSTUNREACH:
     case WSAENETUNREACH:
       return ERR_ADDRESS_UNREACHABLE;
diff --git a/net/udp/udp_socket_libevent.cc b/net/udp/udp_socket_libevent.cc
index f713786..4520c47 100644
--- a/net/udp/udp_socket_libevent.cc
+++ b/net/udp/udp_socket_libevent.cc
@@ -522,7 +522,7 @@ int UDPSocketLibevent::SetSocketOptions() {
 int UDPSocketLibevent::DoBind(const IPEndPoint& address) {
   SockaddrStorage storage;
   if (!address.ToSockAddr(storage.addr, &storage.addr_len))
-    return ERR_UNEXPECTED;
+    return ERR_ADDRESS_INVALID;
   int rv = bind(socket_, storage.addr, storage.addr_len);
   return rv < 0 ? MapSystemError(errno) : rv;
 }
@@ -617,7 +617,7 @@ int UDPSocketLibevent::LeaveGroup(const IPAddressNumber& group_address) const {
 int UDPSocketLibevent::SetMulticastTimeToLive(int time_to_live) {
   DCHECK(CalledOnValidThread());
   if (is_connected())
-    return ERR_UNEXPECTED;
+    return ERR_SOCKET_IS_CONNECTED;
 
   if (time_to_live < 0 || time_to_live > 255)
     return ERR_INVALID_ARGUMENT;
@@ -628,7 +628,7 @@ int UDPSocketLibevent::SetMulticastTimeToLive(int time_to_live) {
 int UDPSocketLibevent::SetMulticastLoopbackMode(bool loopback) {
   DCHECK(CalledOnValidThread());
   if (is_connected())
-    return ERR_UNEXPECTED;
+    return ERR_SOCKET_IS_CONNECTED;
 
   if (loopback)
     socket_options_ |= SOCKET_OPTION_MULTICAST_LOOP;
diff --git a/net/udp/udp_socket_win.cc b/net/udp/udp_socket_win.cc
index b1c5846..c3fd561 100644
--- a/net/udp/udp_socket_win.cc
+++ b/net/udp/udp_socket_win.cc
@@ -615,7 +615,7 @@ int UDPSocketWin::SetSocketOptions() {
 int UDPSocketWin::DoBind(const IPEndPoint& address) {
   SockaddrStorage storage;
   if (!address.ToSockAddr(storage.addr, &storage.addr_len))
-    return ERR_UNEXPECTED;
+    return ERR_ADDRESS_INVALID;
   int rv = bind(socket_, storage.addr, storage.addr_len);
   return rv < 0 ? MapSystemError(WSAGetLastError()) : rv;
 }
@@ -720,7 +720,7 @@ int UDPSocketWin::LeaveGroup(
 int UDPSocketWin::SetMulticastTimeToLive(int time_to_live) {
   DCHECK(CalledOnValidThread());
   if (is_connected())
-    return ERR_UNEXPECTED;
+    return ERR_SOCKET_IS_CONNECTED;
 
   if (time_to_live < 0 || time_to_live > 255)
     return ERR_INVALID_ARGUMENT;
@@ -731,7 +731,7 @@ int UDPSocketWin::SetMulticastTimeToLive(int time_to_live) {
 int UDPSocketWin::SetMulticastLoopbackMode(bool loopback) {
   DCHECK(CalledOnValidThread());
   if (is_connected())
-    return ERR_UNEXPECTED;
+    return ERR_SOCKET_IS_CONNECTED;
 
   if (loopback)
     socket_options_ |= SOCKET_OPTION_MULTICAST_LOOP;