From fe73fcef979f3928714fe87eb06f6f1892faf915 Mon Sep 17 00:00:00 2001
From: Kartikaya Gupta <kgupta@mozilla.com>
Date: Fri, 2 Aug 2013 17:32:48 -0700
Subject: [PATCH] Bug 901187 - Send printf_stderr output to Visual Studio
 console if it is attached. r=bsmedberg

---
 xpcom/glue/nsCRTGlue.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/xpcom/glue/nsCRTGlue.cpp b/xpcom/glue/nsCRTGlue.cpp
index fd9739e4c36..105aba7cde0 100644
--- a/xpcom/glue/nsCRTGlue.cpp
+++ b/xpcom/glue/nsCRTGlue.cpp
@@ -14,6 +14,7 @@
 
 #ifdef XP_WIN
 #include <io.h>
+#include <windows.h>
 #endif
 
 #ifdef ANDROID
@@ -270,6 +271,16 @@ void NS_MakeRandomString(char *aBuf, int32_t aBufLen)
 void
 printf_stderr(const char *fmt, ...)
 {
+  if (IsDebuggerPresent()) {
+    char buf[2048];
+    va_list args;
+    va_start(args, fmt);
+    vsnprintf(buf, sizeof(buf), fmt, args);
+    buf[sizeof(buf) - 1] = '\0';
+    va_end(args);
+    OutputDebugStringA(buf);
+  }
+
   FILE *fp = _fdopen(_dup(2), "a");
   if (!fp)
       return;