win: Implement CrashpadClient::StartHandler()

util/win/exception_handler_server.cc

 // Copyright 2015 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 216 matching lines @@
   WinVMAddress debug_critical_section_address_;
 
   DISALLOW_COPY_AND_ASSIGN(ClientData);
 };
 
 }  // namespace internal
 
 ExceptionHandlerServer::Delegate::~Delegate() {
 }
 
-ExceptionHandlerServer::ExceptionHandlerServer(const std::string& pipe_name)
+ExceptionHandlerServer::ExceptionHandlerServer(const std::string& pipe_name,
+                                               bool persistent)
     : pipe_name_(pipe_name),
       port_(CreateIoCompletionPort(INVALID_HANDLE_VALUE, nullptr, 0, 1)),
       clients_lock_(),
-      clients_() {
+      clients_(),
+      persistent_(persistent) {
 }
 
 ExceptionHandlerServer::~ExceptionHandlerServer() {
 }
 
 void ExceptionHandlerServer::Run(Delegate* delegate) {
   uint64_t shutdown_token = base::RandUint64();
   // We create two pipe instances, so that there's one listening while the
   // PipeServiceProc is processing a registration.
   ScopedKernelHANDLE thread_handles[2];
@@ skipping 38 matching lines @@
     if (!key) {
       // Shutting down.
       break;
     }
 
     // Otherwise, this is a request to unregister and destroy the given client.
     // delete'ing the ClientData blocks in UnregisterWaitEx to ensure all
     // outstanding threadpool waits are complete. This is important because the
     // process handle can be signalled *before* the dump request is signalled.
     internal::ClientData* client = reinterpret_cast<internal::ClientData*>(key);
-    {
-      base::AutoLock lock(clients_lock_);
-      clients_.erase(client);
-    }
+    base::AutoLock lock(clients_lock_);
+    clients_.erase(client);
     delete client;
+    if (!persistent_ && clients_.empty())
+      break;
   }
 
   // Signal to the named pipe instances that they should terminate.
   for (int i = 0; i < arraysize(thread_handles); ++i) {
     ClientToServerMessage message;
     memset(&message, 0, sizeof(message));
     message.type = ClientToServerMessage::kShutdown;
     message.shutdown.token = shutdown_token;
     ServerToClientMessage response;
     SendToCrashHandlerServer(pipe_name_16,
@@ skipping 184 matching lines @@
 void __stdcall ExceptionHandlerServer::OnProcessEnd(void* ctx, BOOLEAN) {
   // This function is executed on the thread pool.
   internal::ClientData* client = reinterpret_cast<internal::ClientData*>(ctx);
   base::AutoLock lock(*client->lock());
 
   // Post back to the main thread to have it delete this client record.
   PostQueuedCompletionStatus(client->port(), 0, ULONG_PTR(client), nullptr);
 }
 
 }  // namespace crashpad