Adds some error handling to the socket implementation.

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 295072836b7d7662bda38ec18450d33425100479..e3d3103eebeb52606d01940d5136e971e0b1feb9 100644
--- a/runtime/bin/socket_linux.cc
+++ b/runtime/bin/socket_linux.cc
@@ -28,6 +28,13 @@
 namespace dart {
 namespace bin {
 
+static void SaveErrorAndClose(intptr_t fd) {
+  int err = errno;
+  VOID_TEMP_FAILURE_RETRY(close(fd));
+  errno = err;
+}
+
+
 SocketAddress::SocketAddress(struct sockaddr* sa) {
   ASSERT(INET6_ADDRSTRLEN >= INET_ADDRSTRLEN);
   if (!Socket::FormatNumericAddress(*reinterpret_cast<RawAddr*>(sa), as_string_,
@@ -69,7 +76,7 @@ static intptr_t Connect(intptr_t fd, const RawAddr& addr) {
   if ((result == 0) || (errno == EINPROGRESS)) {
     return fd;
   }
-  VOID_TEMP_FAILURE_RETRY(close(fd));
+  SaveErrorAndClose(fd);
   return -1;
 }
 
@@ -93,7 +100,7 @@ intptr_t Socket::CreateBindConnect(const RawAddr& addr,
   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));
+    SaveErrorAndClose(fd);
     return -1;
   }
 
@@ -322,7 +329,7 @@ intptr_t Socket::CreateBindDatagram(const RawAddr& addr, bool reuseAddress) {
 
   if (NO_RETRY_EXPECTED(
           bind(fd, &addr.addr, SocketAddress::GetAddrLength(addr))) < 0) {
-    VOID_TEMP_FAILURE_RETRY(close(fd));
+    SaveErrorAndClose(fd);
     return -1;
   }
   return fd;
@@ -408,7 +415,7 @@ intptr_t ServerSocket::CreateBindListen(const RawAddr& addr,
 
   if (NO_RETRY_EXPECTED(
           bind(fd, &addr.addr, SocketAddress::GetAddrLength(addr))) < 0) {
-    VOID_TEMP_FAILURE_RETRY(close(fd));
+    SaveErrorAndClose(fd);
     return -1;
   }
 
@@ -418,14 +425,12 @@ intptr_t ServerSocket::CreateBindListen(const RawAddr& addr,
     // Don't close the socket until we have created a new socket, ensuring
     // that we do not get the bad port number again.
     intptr_t new_fd = CreateBindListen(addr, backlog, v6_only);
-    int err = errno;
-    VOID_TEMP_FAILURE_RETRY(close(fd));
-    errno = err;
+    SaveErrorAndClose(fd);
     return new_fd;
   }
 
   if (NO_RETRY_EXPECTED(listen(fd, backlog > 0 ? backlog : SOMAXCONN)) != 0) {
-    VOID_TEMP_FAILURE_RETRY(close(fd));
+    SaveErrorAndClose(fd);
     return -1;
   }
 
@@ -463,8 +468,14 @@ intptr_t ServerSocket::Accept(intptr_t fd) {
       socket = kTemporaryFailure;
     }
   } else {
-    FDUtils::SetCloseOnExec(socket);
-    FDUtils::SetNonBlocking(socket);
+    if (!FDUtils::SetCloseOnExec(socket)) {
+      SaveErrorAndClose(socket);
+      return -1;
+    }
+    if (!FDUtils::SetNonBlocking(socket)) {
+      SaveErrorAndClose(socket);
+      return -1;
+    }
   }
   return socket;
 }