Avoid recursive DisplayDebugMessageInDialog call when an assert is hit on the IO thread

base/logging.cc

 // Copyright (c) 2010 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/logging.h"
 
 #if defined(OS_WIN)
 #include <io.h>
 #include <windows.h>
 typedef HANDLE FileHandle;
@@ skipping 38 matching lines @@
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/debug/stack_trace.h"
 #include "base/eintr_wrapper.h"
 #include "base/lock_impl.h"
 #if defined(OS_POSIX)
 #include "base/safe_strerror_posix.h"
 #endif
 #include "base/process_util.h"
 #include "base/string_piece.h"
+#include "base/thread_restrictions.h"
 #include "base/utf_string_conversions.h"
 #include "base/vlog.h"
 
 namespace logging {
 
 bool g_enable_dcheck = false;
 VlogInfo* g_vlog_info = NULL;
 
 const char* const log_severity_names[LOG_NUM_SEVERITIES] = {
   "INFO", "WARNING", "ERROR", "ERROR_REPORT", "FATAL" };
@@ skipping 426 matching lines @@
   } else {
     // debug process broken, let's just do a message box
     MessageBoxW(NULL, &cmdline[0], L"Fatal error",
                 MB_OK | MB_ICONHAND | MB_TOPMOST);
   }
 #elif defined(USE_X11) && !defined(OS_CHROMEOS)
   // Shell out to xmessage, which behaves like debug_message.exe, but is
   // way more retro.  We could use zenity/kdialog but then we're starting
   // to get into needing to check the desktop env and this dialog should
   // only be coming up in Very Bad situations.
+  // It is tolerable to allow IO from this function when on any thread, given
+  // we're about to core dump anyway.
+  base::ThreadRestrictions::ScopedAllowIO allow_io;
   std::vector<std::string> argv;
   argv.push_back("xmessage");
   argv.push_back(str);
   base::LaunchApp(argv, base::file_handle_mapping_vector(), true /* wait */,
                   NULL);
 #else
   // http://code.google.com/p/chromium/issues/detail?id=37026
   NOTIMPLEMENTED();
 #endif
 }
@@ skipping 300 matching lines @@
 
   if (level == LOG_FATAL)
     base::debug::BreakDebugger();
 }
 
 }  // namespace logging
 
 std::ostream& operator<<(std::ostream& out, const wchar_t* wstr) {
   return out << WideToUTF8(std::wstring(wstr));
 }