NaCl: Split the debug exception handler thread into a separate file

chrome/common/nacl_debug_exception_handler_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 "chrome/common/nacl_debug_exception_handler_win.h"
+
+#include "base/process_util.h"
+#include "base/threading/platform_thread.h"
+#include "native_client/src/trusted/service_runtime/win/debug_exception_handler.h"
+
+namespace {
+
+class DebugExceptionHandler : public base::PlatformThread::Delegate {
+ public:
+  DebugExceptionHandler(int32 pid,
+                        base::MessageLoopProxy* message_loop,
+                        base::Closure& on_connected)
+      : pid_(pid), message_loop_(message_loop), on_connected_(on_connected) {
+  }
+
+  virtual void ThreadMain() OVERRIDE {
+    // In the Windows API, the set of processes being debugged is
+    // thread-local, so we have to attach to the process (using
+    // DebugActiveProcess()) on the same thread on which
+    // NaClDebugLoop() receives debug events for the process.
+    BOOL attached = false;
+    base::ProcessHandle process_handle = base::kNullProcessHandle;
+    if (!base::OpenProcessHandleWithAccess(
+             pid_,
+             base::kProcessAccessQueryInformation |
+             base::kProcessAccessSuspendResume |
+             base::kProcessAccessTerminate |
+             base::kProcessAccessVMOperation |
+             base::kProcessAccessVMRead |
+             base::kProcessAccessVMWrite |
+             base::kProcessAccessWaitForTermination,
+             &process_handle)) {
+      LOG(ERROR) << "Failed to get process handle";
+    } else {
+      attached = DebugActiveProcess(pid_);
+      if (!attached) {
+        LOG(ERROR) << "Failed to connect to the process";
+      }
+    }
+    // At the moment we do not say in the reply whether attaching as a
+    // debugger succeeded.  In the future, when we attach on demand
+    // when an exception handler is first registered, we can make the
+    // NaCl syscall indicate whether attaching succeeded.
+    message_loop_->PostTask(FROM_HERE, on_connected_);
+
+    if (attached) {
+      DWORD exit_code;
+      NaClDebugLoop(process_handle, &exit_code);
+    }
+    if (process_handle != base::kNullProcessHandle) {
+      base::CloseProcessHandle(process_handle);
+    }
+    delete this;
+  }
+
+ private:
+  int32 pid_;
+  base::MessageLoopProxy* message_loop_;
+  base::Closure on_connected_;
+
+  DISALLOW_COPY_AND_ASSIGN(DebugExceptionHandler);
+};
+
+}  // namespace
+
+void NaClStartDebugExceptionHandlerThread(int32 nacl_process_id,
+                                          base::MessageLoopProxy* message_loop,
+                                          base::Closure& on_connected) {
+  // The new PlatformThread will take ownership of the
+  // DebugExceptionHandler object, which will delete itself on exit.
+  DebugExceptionHandler* handler = new DebugExceptionHandler(
+      nacl_process_id, message_loop, on_connected);
+  if (!base::PlatformThread::CreateNonJoinable(0, handler)) {
+    on_connected.Run();
+    delete handler;
+  }
+}