Add support to specify the source address for socket connect

runtime/bin/socket_linux.cc

Index: runtime/bin/socket_linux.cc
diff --git a/runtime/bin/socket_linux.cc b/runtime/bin/socket_linux.cc
index c6e1fe1a885298ce14ab11e6416deb64d4c82ecd..74f7fbb3a9a58e11e41f7dbfa7c105e83298838a 100644
--- a/runtime/bin/socket_linux.cc
+++ b/runtime/bin/socket_linux.cc
@@ -52,7 +52,7 @@ bool Socket::Initialize() {
 }
 
 
-intptr_t Socket::Create(RawAddr addr) {
+static intptr_t Create(RawAddr addr) {
   intptr_t fd;
   fd = NO_RETRY_EXPECTED(
       socket(addr.ss.ss_family, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0));
@@ -63,7 +63,7 @@ intptr_t Socket::Create(RawAddr addr) {
 }
 
 
-intptr_t Socket::Connect(intptr_t fd, RawAddr addr, const intptr_t port) {
+static intptr_t Connect(intptr_t fd, RawAddr addr, const intptr_t port) {
   SocketAddress::SetAddrPort(&addr, port);
   intptr_t result = TEMP_FAILURE_RETRY(
       connect(fd, &addr.addr, SocketAddress::GetAddrLength(&addr)));
@@ -76,11 +76,30 @@ intptr_t Socket::Connect(intptr_t fd, RawAddr addr, const intptr_t port) {
 
 
 intptr_t Socket::CreateConnect(RawAddr addr, const intptr_t port) {
-  intptr_t fd = Socket::Create(addr);
+  intptr_t fd = Create(addr);
   if (fd < 0) {
     return fd;
   }
-  return Socket::Connect(fd, addr, port);
+  return Connect(fd, addr, port);
+}
+
+
+intptr_t Socket::CreateBindConnect(RawAddr addr,
+                                   const intptr_t port,
+                                   RawAddr source_addr) {
+  intptr_t fd = Create(addr);
+  if (fd < 0) {
+    return fd;
+  }
+
+  intptr_t result = TEMP_FAILURE_RETRY(
+      bind(fd, &source_addr.addr, SocketAddress::GetAddrLength(&source_addr)));
+  if (result != 0 && errno != EINPROGRESS) {
+    VOID_TEMP_FAILURE_RETRY(close(fd));
+    return -1;
+  }
+
+  return Connect(fd, addr, port);
 }