gears/localserver/firefox/update_task_ff.cc

   1 // Copyright 2006, Google Inc.
   2 //
   3 // Redistribution and use in source and binary forms, with or without
   4 // modification, are permitted provided that the following conditions are met:
   5 //
   6 //  1. Redistributions of source code must retain the above copyright notice,
   7 //     this list of conditions and the following disclaimer.
   8 //  2. Redistributions in binary form must reproduce the above copyright notice,
   9 //     this list of conditions and the following disclaimer in the documentation
  10 //     and/or other materials provided with the distribution.
  11 //  3. Neither the name of Google Inc. nor the names of its contributors may be
  12 //     used to endorse or promote products derived from this software without
  13 //     specific prior written permission.
  14 //
  15 // THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  16 // WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  17 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
  18 // EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  19 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20 // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  21 // OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  22 // WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  23 // OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  24 // ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25
  26 #include <assert.h>
  27 #include <map>
  28 #include "gears/base/common/mutex.h"
  29 #include "gears/localserver/firefox/update_task_ff.h"
  30
  31 // We use a global map to ensure that only one update task per captured
  32 // application executes at a time. Since Firefox only runs in a single
  33 // process, this mutual exclusion only needs to work across threads rather
  34 // than across processes.
  35 typedef std::map< int64, FFUpdateTask* > UpdateTaskMap;
  36 static Mutex running_tasks_mutex;
  37 static UpdateTaskMap running_tasks;
  38
  39 void FFUpdateTask::Run() {
  40   if (SetRunningTask(this)) {
  41     UpdateTask::Run();
  42     ClearRunningTask(this);
  43   } else {
  44     LOG(("FFUpdateTask - not running, another task is already running\n"));
  45     NotifyTaskComplete(false);
  46   }
  47 }
  48
  49 // static
  50 bool FFUpdateTask::SetRunningTask(FFUpdateTask *task) {
  51   MutexLock lock(&running_tasks_mutex);
  52   int64 key = task->store_.GetServerID();
  53   UpdateTaskMap::iterator found = running_tasks.find(key);
  54   if (found != running_tasks.end()) {
  55     // An existing entry indicates another task is running, return false
  56     // to prevent Run from proceeding.
  57     return false;
  58   } else {
  59     running_tasks[key] = task;
  60     return true;
  61   }
  62 }
  63
  64 // static
  65 void FFUpdateTask::ClearRunningTask(FFUpdateTask *task) {
  66   MutexLock lock(&running_tasks_mutex);
  67   int64 key = task->store_.GetServerID();
  68   UpdateTaskMap::iterator found = running_tasks.find(key);
  69   if (found != running_tasks.end()) {
  70     assert(found->second == task);
  71     running_tasks.erase(found);
  72   }
  73 }
  74
  75 // Platform-specific implementation. See declaration in update_task.h.
  76 // Returns true if an UpdateTask for the given store is running
  77 bool UpdateTask::IsUpdateTaskForStoreRunning(int64 store_server_id) {
  78   MutexLock lock(&running_tasks_mutex);
  79   UpdateTaskMap::iterator found = running_tasks.find(store_server_id);
  80   return (found != running_tasks.end());
  81 }
  82
  83 // Platform-specific implementation. See declaration in update_task.h.
  84 UpdateTask *UpdateTask::CreateUpdateTask() {
  85   return new FFUpdateTask();
  86 }