handler: Add crash report upload. Almost

handler/mac/crash_report_upload_thread.h

+// 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_HANDLER_MAC_CRASH_REPORT_UPLOAD_THREAD_H_
+#define CRASHPAD_HANDLER_MAC_CRASH_REPORT_UPLOAD_THREAD_H_
+
+#include "base/basictypes.h"
+
+#include <pthread.h>
+
+#include "client/crash_report_database.h"
+#include "util/synchronization/semaphore.h"
+
+namespace crashpad {
+
+//! \brief A thread that processes pending crash reports in a
+//!     CrashReportDatabase by uploading them or marking them as completed
+//!     without upload, as desired.
+//!
+//! A producer of crash reports should notify an object of this class that a new
+//! report has been added to the database by calling ReportPending().
+//!
+//! Independently of being triggered by ReportPending(), objects of this class
+//! periodically examine the database for pending reports. This allows failed
+//! upload attempts for reports left in the pending state to be retried. It also
+//! catches reports that are added without a ReportPending() signal being
+//! caught. This may happen if crash reports are added to the database by other
+//! processes.
+class CrashReportUploadThread {
+ public:
+  explicit CrashReportUploadThread(CrashReportDatabase* database);
+  ~CrashReportUploadThread();
+
+  //! \brief Starts a dedicated upload thread, which executes ThreadMain().
+  //!
+  //! This method may only be be called on a newly-constructed object or after
+  //! a call to Stop().
+  void Start();
+
+  //! \brief Stops the upload thread.
+  //!
+  //! The upload thread will terminate after completing whatever task it is
+  //! performing. If it is not performing any task, it will terminate
+  //! immediately. This method blocks while waiting for the upload thread to
+  //! terminate.
+  //!
+  //! This method must only be called after Start(). If Start() has been called,
+  //! this method must be called before destroying an object of this class.
+  //!
+  //! This method may be called from any thread other than the upload thread.
+  //! It is expected to only be called from the same thread that called Start().
+  void Stop();
+
+  //! \brief Informs the upload thread that a new pending report has been added
+  //!     to the database.
+  //!
+  //! This method may be called from any thread.
+  void ReportPending();
+
+ private:
+  //! \brief Calls ProcessPendingReports() in response to ReportPending() having
+  //!     been called on any thread, as well as periodically on a timer.
+  void ThreadMain();
+
+  //! \brief Obtains all pending reports from the database, and calls
+  //!     ProcessPendingReport() to process each one.
+  void ProcessPendingReports();
+
+  //! \brief Processes a single pending report from the database.
+  //!
+  //! \param[in] report The crash report to process.
+  //!
+  //! If report upload is enabled, this method attempts to upload \a report. If
+  //! the upload is successful, the report will be marked as “completed” in the
+  //! database. If the upload fails and more retries are desired, the report’s
+  //! upload-attempt count and last-upload-attempt time will be updated in the
+  //! database and it will remain in the “pending” state. If the upload fails
+  //! and no more retries are desired, or report upload is disabled, it will be
+  //! marked as “completed” in the database without ever having been uploaded.
+  void ProcessPendingReport(const CrashReportDatabase::Report& report);
+
+  //! \brief Cals ThreadMain().
+  //!
+  //! \param[in] arg A pointer to the object on which to invoke ThreadMain().
+  //!
+  //! \return `nullptr`.
+  static void* RunThreadMain(void* arg);
+
+  CrashReportDatabase* database_;  // weak
+  Semaphore semaphore_;  // TODO(mark): Use a condition variable instead?
+  pthread_t thread_;
+  bool running_;
+};
+
+}  // namespace crashpad
+
+#endif  // CRASHPAD_HANDLER_MAC_CRASH_REPORT_UPLOAD_THREAD_H_