Adding crash utilities to chromecast/crash.

chromecast/crash/minidump_manager.h

+// 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.
+
+#ifndef CHROMECAST_CRASH_MINIDUMP_MANAGER_H_
+#define CHROMECAST_CRASH_MINIDUMP_MANAGER_H_
+
+#include <string>
+
+#include "base/macros.h"
+
+namespace chromecast {
+
+// Abstract class for minidump handling. Ensures synchronized access to
+// minidumps using a file lock.
+class MinidumpManager {
+ public:
+  virtual ~MinidumpManager();
+
+  // Acquires file lock, calls doWork(), then releases file lock.
+  // Returns the status of doWork(), or -1 if the lock could not be acquired.
+  int DoWorkLocked();
+
+  // Returns whether this object's file locking method is nonblocking or not.
+  bool nonblocking() { return nonblocking_; }
+
+  // Sets the file locking mechansim to be nonblocking or not.
+  void SetNonblocking(bool nonblocking) { nonblocking_ = nonblocking; }
+
+ protected:
+  MinidumpManager();
+
+  // Overriden by child classes doing a specific operation to minidumps
+  virtual int DoWork() = 0;
+
+  // Get the number of un-uploaded dumps in the dump_path directory.
+  // If delete_all_dumps is true, also delete all these files, this is used to
+  // clean lingering dump files.
+  int GetNumDumps(bool delete_all_dumps);
+
+  // If true, the flock on the lockfile will be nonblocking
+  bool nonblocking_;
+
+  // cached string storing the dump path directory retrieved from system
+  // properties, or empty string if property does not exist
+  std::string dump_path_;
+
+  // cached string storing the lockfile path
+  std::string lockfile_path_;
+
+ private:
+  // Acquire the lock file. Blocks if another process holds it, or if called
+  // a second time by the same process. Returns the fd of the lockfile if
+  // successful, or -1 if failed.
+  int AcquireLockFile();
+  // Release the lock file with the associated *fd*.
+  void ReleaseLockFile();
+
+  // the lockfile fd, or -1 if not open
+  int lockfile_fd_;
+
+  DISALLOW_COPY_AND_ASSIGN(MinidumpManager);
+};
+
+}  // namespace chromecast
+
+#endif  // CHROMECAST_CRASH_MINIDUMP_MANAGER_H_