Make printf and LOG output to cmd console for Windows

base/process_util_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/process_util.h"
 
 #include <fcntl.h>
 #include <io.h>
 #include <windows.h>
 #include <userenv.h>
@@ skipping 51 matching lines @@
 
 // Prints the exception call stack.
 // This is the unit tests exception filter.
 long WINAPI StackDumpExceptionFilter(EXCEPTION_POINTERS* info) {
   debug::StackTrace(info).PrintBacktrace();
   if (g_previous_filter)
     return g_previous_filter(info);
   return EXCEPTION_CONTINUE_SEARCH;
 }
 
-// Connects back to a console if available.
-void AttachToConsole() {
-  if (!AttachConsole(ATTACH_PARENT_PROCESS)) {
-    unsigned int result = GetLastError();
-    // Was probably already attached.
-    if (result == ERROR_ACCESS_DENIED)
-      return;
-
-    if (result == ERROR_INVALID_HANDLE || result == ERROR_INVALID_HANDLE) {
-      // TODO(maruel): Walk up the process chain if deemed necessary.
-    }
-    // Continue even if the function call fails.
-    AllocConsole();
-  }
-  // http://support.microsoft.com/kb/105305
-  int raw_out = _open_osfhandle(
-      reinterpret_cast<intptr_t>(GetStdHandle(STD_OUTPUT_HANDLE)), _O_TEXT);
-  *stdout = *_fdopen(raw_out, "w");
-  setvbuf(stdout, NULL, _IONBF, 0);
-
-  int raw_err = _open_osfhandle(
-      reinterpret_cast<intptr_t>(GetStdHandle(STD_ERROR_HANDLE)), _O_TEXT);
-  *stderr = *_fdopen(raw_err, "w");
-  setvbuf(stderr, NULL, _IONBF, 0);
-
-  int raw_in = _open_osfhandle(
-      reinterpret_cast<intptr_t>(GetStdHandle(STD_INPUT_HANDLE)), _O_TEXT);
-  *stdin = *_fdopen(raw_in, "r");
-  setvbuf(stdin, NULL, _IONBF, 0);
-  // Fix all cout, wcout, cin, wcin, cerr, wcerr, clog and wclog.
-  std::ios::sync_with_stdio();
-}
-
 void OnNoMemory() {
   // Kill the process. This is important for security, since WebKit doesn't
   // NULL-check many memory allocations. If a malloc fails, returns NULL, and
   // the buffer is then used, it provides a handy mapping of memory starting at
   // address 0 for an attacker to utilize.
   __debugbreak();
   _exit(1);
 }
 
 class TimerExpiredTask : public win::ObjectWatcher::Delegate {
@@ skipping 45 matching lines @@
   // TerminateProcess should do for us. Don't check for the result code since
   // it fails quite often. This should be investigated eventually.
   base::KillProcess(process_, kProcessKilledExitCode, false);
 
   // Now, just cleanup as if the process exited normally.
   OnObjectSignaled(process_);
 }
 
 }  // namespace
 
+void RouteStdioToConsole() {
+  if (!AttachConsole(ATTACH_PARENT_PROCESS)) {
+    unsigned int result = GetLastError();
+    // Was probably already attached.
+    if (result == ERROR_ACCESS_DENIED)
+      return;
+    // Don't bother creating a new console for each child process if the
+    // parent process is invalid (eg: crashed).
+    if (result == ERROR_GEN_FAILURE)
+      return;
+    // Make a new console if attaching to parent fails with any other error.
+    // It should be ERROR_INVALID_HANDLE at this point, which means the browser
+    // was likely not started from a console.
+    AllocConsole();
+  }
+
+  if (freopen("CONOUT$", "w", stdout))
+    setvbuf(stdout, NULL, _IONBF, 0);
+  if (freopen("CONERR$", "w", stderr))
+    setvbuf(stderr, NULL, _IONBF, 0);
+
+  // Fix all cout, wcout, cin, wcin, cerr, wcerr, clog and wclog.
+  std::ios::sync_with_stdio();
+}
+
 ProcessId GetCurrentProcId() {
   return ::GetCurrentProcessId();
 }
 
 ProcessHandle GetCurrentProcessHandle() {
   return ::GetCurrentProcess();
 }
 
 HMODULE GetModuleFromAddress(void* address) {
   HMODULE instance = NULL;
@@ skipping 767 matching lines @@
 }
 
 void EnableTerminationOnOutOfMemory() {
   std::set_new_handler(&OnNoMemory);
 }
 
 bool EnableInProcessStackDumping() {
   // Add stack dumping support on exception on windows. Similar to OS_POSIX
   // signal() handling in process_util_posix.cc.
   g_previous_filter = SetUnhandledExceptionFilter(&StackDumpExceptionFilter);
-  AttachToConsole();
+  RouteStdioToConsole();
   return true;
 }
 
 void RaiseProcessToHighPriority() {
   SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS);
 }
 
 // GetPerformanceInfo is not available on WIN2K.  So we'll
 // load it on-the-fly.
 const wchar_t kPsapiDllName[] = L"psapi.dll";
@@ skipping 27 matching lines @@
 
   PERFORMANCE_INFORMATION info;
   if (!InternalGetPerformanceInfo(&info, sizeof(info))) {
     DLOG(ERROR) << "Failed to fetch internal performance info.";
     return 0;
   }
   return (info.CommitTotal * system_info.dwPageSize) / 1024;
 }
 
 }  // namespace base