Make socket send and receive more robust and return 0 on failure.

R=jkummerow@chromium.org
BUG=15719
TEST=

Review URL: https://chromiumcodereview.appspot.com/10412021

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11601 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/debug-agent.cc

-// Copyright 2009 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -247,7 +247,7 @@ SmartArrayPointer<char> DebuggerAgentUtil::ReceiveMessage(const Socket* conn) {
     while (!(c == '\n' && prev_c == '\r')) {
       prev_c = c;
       received = conn->Receive(&c, 1);
-      if (received <= 0) {
+      if (received == 0) {
         PrintF("Error %d\n", Socket::LastError());
         return SmartArrayPointer<char>();
       }
@@ -454,7 +454,7 @@ int DebuggerAgentUtil::ReceiveAll(const Socket* conn, char* data, int len) {
   int total_received = 0;
   while (total_received < len) {
     int received = conn->Receive(data + total_received, len - total_received);
-    if (received <= 0) {
+    if (received == 0) {
       return total_received;
     }
     total_received += received;

src/platform-posix.cc

-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -467,14 +467,16 @@ bool POSIXSocket::Shutdown() {
 
 
 int POSIXSocket::Send(const char* data, int len) const {
+  if (len <= 0) return 0;
   int status = send(socket_, data, len, 0);
-  return status;
+  return (status < 0) ? 0 : status;
 }
 
 
 int POSIXSocket::Receive(char* data, int len) const {
+  if (len <= 0) return 0;
   int status = recv(socket_, data, len, 0);
-  return status;
+  return (status < 0) ? 0 : status;
 }
 
 

src/platform-win32.cc

@@ -1848,14 +1848,16 @@ bool Win32Socket::Shutdown() {
 
 
 int Win32Socket::Send(const char* data, int len) const {
+  if (len <= 0) return 0;
   int status = send(socket_, data, len, 0);
-  return status;
+  return (status == SOCKET_ERROR) ? 0 : status;
 }
 
 
 int Win32Socket::Receive(char* data, int len) const {
+  if (len <= 0) return 0;
   int status = recv(socket_, data, len, 0);
-  return status;
+  return (status == SOCKET_ERROR) ? 0 : status;
 }
 
 

src/platform.h

-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -653,6 +653,7 @@ class Socket {
   virtual bool Shutdown() = 0;
 
   // Data Transimission
+  // Return 0 on failure.
   virtual int Send(const char* data, int len) const = 0;
   virtual int Receive(char* data, int len) const = 0;