Make Crashpad start asynchronous, and move back to chrome_elf

components/crash/content/app/crashpad_win.cc

 // Copyright 2015 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 "components/crash/content/app/crashpad.h"
 
 #include <memory>
 
 #include "base/debug/crash_logging.h"
 #include "base/environment.h"
@@ skipping 100 matching lines @@
       arguments.push_back(std::string("--type=") + switches::kCrashpadHandler);
       // The prefetch argument added here has to be documented in
       // chrome_switches.cc, below the kPrefetchArgument* constants. A constant
       // can't be used here because crashpad can't depend on Chrome.
       arguments.push_back("/prefetch:7");
     } else {
       base::FilePath exe_dir = exe_file.DirName();
       exe_file = exe_dir.Append(FILE_PATH_LITERAL("crashpad_handler.exe"));
     }
 
-    g_crashpad_client.Get().StartHandler(
-        exe_file, database_path, metrics_path, url, process_annotations,
-        arguments, false, false);
+    if (!g_crashpad_client.Get().StartHandler(
+            exe_file, database_path, metrics_path, url, process_annotations,
+            arguments, false, true)) {
+      // This means that CreateThread() failed, so this process is very messed
+      // up. This should be effectively unreachable. Note that if this is
+      // converted to non-fatal, calls to BlockUntilHandlerStarted() will have

[robertshield, 2016/12/15 20:06:30]

nit: consider updating the comment about "if this is converted to non-fatal". As
discussed we probably don't ever want to do this conversion.

[scottmg, 2016/12/16 17:16:51]

Done.

+      // to be amended.
+      LOG(FATAL) << "synchronous part of handler startup failed";
+    }
 
     // If we're the browser, push the pipe name into the environment so child
     // processes can connect to it. If we inherited another crashpad_handler's
     // pipe name, we'll overwrite it here.
     env->SetVar(kPipeNameVar,
                 base::UTF16ToUTF8(g_crashpad_client.Get().GetHandlerIPCPipe()));
   } else {
     std::string pipe_name_utf8;
     if (env->GetVar(kPipeNameVar, &pipe_name_utf8)) {
       g_crashpad_client.Get().SetHandlerIPCPipe(
@@ skipping 67 matching lines @@
   VLOG(1) << "dumped for hang debugging";
   return 0;
 }
 
 MSVC_POP_WARNING()
 MSVC_ENABLE_OPTIMIZE()
 
 }  // namespace
 
 }  // namespace internal
+
+void BlockUntilHandlerStarted() {
+  // We know that the StartHandler() at least started asynchronous startup if
+  // we're here, as if it doesn't, we abort.
+  const unsigned int kTimeoutMS = 5000;
+  if (!internal::g_crashpad_client.Get().WaitForHandlerStart(kTimeoutMS)) {
+    LOG(ERROR) << "Crashpad handler failed to start, crash reporting disabled";
+  }
+}
+
 }  // namespace crash_reporter
 
 extern "C" {
 
 // Crashes the process after generating a dump for the provided exception. Note
 // that the crash reporter should be initialized before calling this function
 // for it to do anything.
 // NOTE: This function is used by SyzyASAN to invoke a crash. If you change the
 // the name or signature of this function you will break SyzyASAN instrumented
 // releases of Chrome. Please contact syzygy-team@chromium.org before doing so!
@@ skipping 122 matching lines @@
 void __declspec(dllexport) __cdecl UnregisterNonABICompliantCodeRange(
     void* start) {
   ExceptionHandlerRecord* record =
       reinterpret_cast<ExceptionHandlerRecord*>(start);
 
   CHECK(RtlDeleteFunctionTable(&record->runtime_function));
 }
 #endif  // ARCH_CPU_X86_64
 
 }  // extern "C"