src/TGitCache/FolderCrawler.h

   1 // TortoiseGit - a Windows shell extension for easy version control
   2
   3 // External Cache Copyright (C) 2005 - 2006 - Will Dean, Stefan Kueng
   4 // Copyright (C) 2008-2011 - 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 #pragma once
  21
  22 #include "TGitPath.h"
  23 #include "CacheInterface.h"
  24 #include <set>
  25 //////////////////////////////////////////////////////////////////////////
  26
  27
  28
  29 #pragma pack(push, r1, 16)
  30
  31 /**
  32  * \ingroup TSVNCache
  33  * Helper class to crawl folders in the background (in a separate thread)
  34  * so that the main cache isn't blocked until all the status are fetched.
  35  */
  36 class CFolderCrawler
  37 {
  38 public:
  39         CFolderCrawler(void);
  40         ~CFolderCrawler(void);
  41
  42 public:
  43         void Initialise();
  44         void AddDirectoryForUpdate(const CTGitPath& path);
  45         void AddPathForUpdate(const CTGitPath& path);
  46         void Stop();
  47         bool SetHoldoff(DWORD milliseconds = 100);
  48         void BlockPath(const CTGitPath& path, DWORD ticks = 0);
  49 private:
  50         static unsigned int __stdcall ThreadEntry(void* pContext);
  51         void WorkerThread();
  52
  53 private:
  54         CComAutoCriticalSection m_critSec;
  55         HANDLE m_hThread;
  56         std::deque<CTGitPath> m_foldersToUpdate;
  57         std::deque<CTGitPath> m_pathsToUpdate;
  58
  59         void RemoveDuplicate(std::deque<CTGitPath> &list,const CTGitPath &path);
  60
  61         HANDLE m_hTerminationEvent;
  62         HANDLE m_hWakeEvent;
  63
  64         // This will be *asynchronously* modified by CCrawlInhibitor.
  65         // So, we have to mark it volatile, preparing compiler and
  66         // optimizer for the "worst".
  67         volatile LONG m_lCrawlInhibitSet;
  68
  69         // While the shell is still asking for items, we don't
  70         // want to start crawling.  This timer is pushed-out for
  71         // every shell request, and stops us crawling until
  72         // a bit of quiet time has elapsed
  73         long m_crawlHoldoffReleasesAt;
  74         bool m_bItemsAddedSinceLastCrawl;
  75         bool m_bPathsAddedSinceLastCrawl;
  76
  77         CTGitPath m_blockedPath;
  78         DWORD m_blockReleasesAt;
  79         bool m_bRun;
  80
  81
  82         friend class CCrawlInhibitor;
  83 };
  84
  85
  86 //////////////////////////////////////////////////////////////////////////
  87
  88
  89 class CCrawlInhibitor
  90 {
  91 private:
  92         CCrawlInhibitor(); // Not defined
  93 public:
  94         explicit CCrawlInhibitor(CFolderCrawler* pCrawler)
  95         {
  96                 m_pCrawler = pCrawler;
  97
  98                 // Count locks instead of a mere flag toggle (exchange)
  99                 // to allow for multiple, concurrent locks.
 100                 ::InterlockedIncrement(&m_pCrawler->m_lCrawlInhibitSet);
 101         }
 102         ~CCrawlInhibitor()
 103         {
 104                 ::InterlockedDecrement(&m_pCrawler->m_lCrawlInhibitSet);
 105                 m_pCrawler->SetHoldoff();
 106         }
 107 private:
 108         CFolderCrawler* m_pCrawler;
 109 };
 110
 111 #pragma pack(pop, r1)