Add support to specify the source address for socket connect

runtime/bin/socket_macos.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_MACOS)
 
 #include <errno.h>  // NOLINT
 #include <stdio.h>  // NOLINT
 #include <stdlib.h>  // NOLINT
@@ skipping 39 matching lines @@
   return true;
 }
 
 
 bool Socket::Initialize() {
   // Nothing to do on Mac OS.
   return true;
 }
 
 
-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, 0));
   if (fd < 0) {
     return -1;
   }
   FDUtils::SetCloseOnExec(fd);
   return fd;
 }
 
 
-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)));
   if (result == 0 || errno == EINPROGRESS) {
     return fd;
   }
   VOID_TEMP_FAILURE_RETRY(close(fd));
   return -1;
 }
 
 
-intptr_t Socket::CreateConnect(RawAddr addr, const intptr_t port) {
-  intptr_t fd = Socket::Create(addr);
+intptr_t Socket::CreateConnect(const RawAddr& addr, const intptr_t port) {
+  intptr_t fd = Create(addr);
   if (fd < 0) {
     return fd;
   }
 
   FDUtils::SetNonBlocking(fd);
 
-  return Socket::Connect(fd, addr, port);
+  return Connect(fd, addr, port);
 }
 
 
+intptr_t Socket::CreateBindConnect(const RawAddr& addr,
+                                   const intptr_t port,
+                                   const 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);
+}
+
+
 intptr_t Socket::Available(intptr_t fd) {
   return FDUtils::AvailableBytes(fd);
 }
 
 
 intptr_t Socket::Read(intptr_t fd, void* buffer, intptr_t num_bytes) {
   ASSERT(fd >= 0);
   ssize_t read_bytes = TEMP_FAILURE_RETRY(read(fd, buffer, num_bytes));
   ASSERT(EAGAIN == EWOULDBLOCK);
   if (read_bytes == -1 && errno == EWOULDBLOCK) {
@@ skipping 489 matching lines @@
 
 bool Socket::LeaveMulticast(
     intptr_t fd, RawAddr* addr, RawAddr* interface, int interfaceIndex) {
   return JoinOrLeaveMulticast(fd, addr, interface, interfaceIndex, false);
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)