src/TGitCache/ShellUpdater.cpp

   1 // TortoiseGit - a Windows shell extension for easy version control
   2
   3 // External Cache Copyright (C) 2005-2008 - TortoiseSVN
   4 // Copyright (C) 2008-2011,2013,2015-2017 - TortoiseGit
   5
   6 // This program is free software; you can redistribute it and/or
   7 // modify it under the terms of the GNU General Public License
   8 // as published by the Free Software Foundation; either version 2
   9 // of the License, or (at your option) any later version.
  10
  11 // This program is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License
  17 // along with this program; if not, write to the Free Software Foundation,
  18 // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 //
  20
  21 #include "stdafx.h"
  22 #include <ShlObj.h>
  23 #include "GitAdminDir.h"
  24 #include "GitStatusCache.h"
  25
  26 CShellUpdater::CShellUpdater(void)
  27         : m_bRunning(FALSE)
  28         , m_bItemsAddedSinceLastUpdate(false)
  29 {
  30         m_hWakeEvent = CreateEvent(nullptr, FALSE, FALSE, nullptr);
  31         m_hTerminationEvent = CreateEvent(nullptr, TRUE, FALSE, nullptr);
  32 }
  33
  34 CShellUpdater::~CShellUpdater(void)
  35 {
  36         Stop();
  37 }
  38
  39 void CShellUpdater::Stop()
  40 {
  41         InterlockedExchange(&m_bRunning, FALSE);
  42         if (m_hTerminationEvent)
  43         {
  44                 SetEvent(m_hTerminationEvent);
  45                 if(WaitForSingleObject(m_hThread, 200) != WAIT_OBJECT_0)
  46                         CTraceToOutputDebugString::Instance()(__FUNCTION__ ": Error terminating shell updater thread\n");
  47         }
  48         m_hThread.CloseHandle();
  49         m_hTerminationEvent.CloseHandle();
  50         m_hWakeEvent.CloseHandle();
  51 }
  52
  53 void CShellUpdater::Initialise()
  54 {
  55         // Don't call Initialize more than once
  56         ATLASSERT(!m_hThread);
  57
  58         // Just start the worker thread.
  59         // It will wait for event being signaled.
  60         // If m_hWakeEvent is already signaled the worker thread
  61         // will behave properly (with normal priority at worst).
  62
  63         InterlockedExchange(&m_bRunning, TRUE);
  64         unsigned int threadId;
  65         m_hThread = (HANDLE)_beginthreadex(nullptr, 0, ThreadEntry, this, 0, &threadId);
  66         SetThreadPriority(m_hThread, THREAD_PRIORITY_LOWEST);
  67 }
  68
  69 void CShellUpdater::AddPathForUpdate(const CTGitPath& path)
  70 {
  71         {
  72                 AutoLocker lock(m_critSec);
  73
  74                 m_pathsToUpdate.push_back(path);
  75
  76                 // set this flag while we are synced
  77                 // with the worker thread
  78                 m_bItemsAddedSinceLastUpdate = true;
  79         }
  80
  81         SetEvent(m_hWakeEvent);
  82 }
  83
  84
  85 unsigned int CShellUpdater::ThreadEntry(void* pContext)
  86 {
  87         reinterpret_cast<CShellUpdater*>(pContext)->WorkerThread();
  88         return 0;
  89 }
  90
  91 void CShellUpdater::WorkerThread()
  92 {
  93         HANDLE hWaitHandles[2];
  94         hWaitHandles[0] = m_hTerminationEvent;
  95         hWaitHandles[1] = m_hWakeEvent;
  96
  97         for(;;)
  98         {
  99                 DWORD waitResult = WaitForMultipleObjects(_countof(hWaitHandles), hWaitHandles, FALSE, INFINITE);
 100
 101                 // exit event/working loop if the first event (m_hTerminationEvent)
 102                 // has been signaled or if one of the events has been abandoned
 103                 // (i.e. ~CShellUpdater() is being executed)
 104                 if(waitResult == WAIT_OBJECT_0 || waitResult == WAIT_ABANDONED_0 || waitResult == WAIT_ABANDONED_0+1)
 105                 {
 106                         // Termination event
 107                         break;
 108                 }
 109                 // wait some time before we notify the shell
 110                 Sleep(50);
 111                 for(;;)
 112                 {
 113                         CTGitPath workingPath;
 114                         if (!m_bRunning)
 115                                 return;
 116                         Sleep(0);
 117                         {
 118                                 AutoLocker lock(m_critSec);
 119                                 if(m_pathsToUpdate.empty())
 120                                 {
 121                                         // Nothing left to do
 122                                         break;
 123                                 }
 124
 125                                 if(m_bItemsAddedSinceLastUpdate)
 126                                 {
 127                                         m_pathsToUpdate.erase(std::unique(m_pathsToUpdate.begin(), m_pathsToUpdate.end(), &CTGitPath::PredLeftEquivalentToRight), m_pathsToUpdate.end());
 128                                         m_bItemsAddedSinceLastUpdate = false;
 129                                 }
 130
 131                                 workingPath = m_pathsToUpdate.front();
 132                                 m_pathsToUpdate.pop_front();
 133                         }
 134                         if (workingPath.IsEmpty())
 135                                 continue;
 136                         CTraceToOutputDebugString::Instance()(_T(__FUNCTION__) L": shell notification for %s\n", workingPath.GetWinPath());
 137                         if (workingPath.IsDirectory())
 138                         {
 139                                 // first send a notification about a sub folder change, so explorer doesn't discard
 140                                 // the folder notification. Since we only know for sure that the git admin
 141                                 // dir is present, we send a notification for that folder.
 142                                 CString admindir(workingPath.GetWinPathString());
 143                                 admindir += L'\\';
 144                                 admindir += GitAdminDir::GetAdminDirName();
 145                                 if(::PathFileExists(admindir))
 146                                         SHChangeNotify(SHCNE_UPDATEITEM, SHCNF_PATH | SHCNF_FLUSHNOWAIT, (LPCTSTR)admindir, nullptr);
 147
 148                                 SHChangeNotify(SHCNE_UPDATEITEM, SHCNF_PATH | SHCNF_FLUSHNOWAIT, workingPath.GetWinPath(), nullptr);
 149                                 // Sending an UPDATEDIR notification somehow overwrites/deletes the UPDATEITEM message. And without
 150                                 // that message, the folder overlays in the current view don't get updated without hitting F5.
 151                                 // Drawback is, without UPDATEDIR, the left tree view isn't always updated...
 152
 153                                 //SHChangeNotify(SHCNE_UPDATEDIR, SHCNF_PATH | SHCNF_FLUSHNOWAIT, workingPath.GetWinPath(), nullptr);
 154                         }
 155                         else
 156                                 SHChangeNotify(SHCNE_UPDATEITEM, SHCNF_PATH | SHCNF_FLUSHNOWAIT, workingPath.GetWinPath(), nullptr);
 157                 }
 158         }
 159         _endthread();
 160 }
 161