src/TortoiseShell/PreserveChdir.cpp

   1 // TortoiseGit - a Windows shell extension for easy version control
   2
   3 // Copyright (C) 2016 - TortoiseGit
   4 // Copyright (C) 2003-2007 - TortoiseSVN
   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 #include "stdafx.h"
  21 #include "PreserveChdir.h"
  22
  23 PreserveChdir::PreserveChdir()
  24 {
  25         DWORD len = GetCurrentDirectory(0, nullptr);
  26         if (!len)
  27                 return;
  28
  29         m_originalCurrentDirectory = std::make_unique<TCHAR[]>(len);
  30         if (GetCurrentDirectory(len, m_originalCurrentDirectory.get()) == 0)
  31                 m_originalCurrentDirectory.reset();
  32 }
  33
  34 PreserveChdir::~PreserveChdir()
  35 {
  36         if (!m_originalCurrentDirectory)
  37                 return;
  38
  39         DWORD len = GetCurrentDirectory(0, nullptr);
  40         auto currentDirectory = std::make_unique<TCHAR[]>(len);
  41
  42         // _tchdir is an expensive function - don't call it unless we really have to
  43         GetCurrentDirectory(len, currentDirectory.get());
  44         if (wcscmp(currentDirectory.get(), m_originalCurrentDirectory.get()) != 0)
  45                 SetCurrentDirectory(m_originalCurrentDirectory.get());
  46 }