src/Utils/CreateProcessHelper.h

   1 // TortoiseGit - a Windows shell extension for easy version control
   2
   3 // Copyright (C) 2016 - TortoiseGit
   4 // Copyright (C) 2009-2010 - 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 #pragma once
  21 #include "scope_exit_noexcept.h"
  22
  23 /**
  24  * A helper class for invoking CreateProcess(). The lpProcessInformation
  25  * can point to an uninitialized struct - it's memset to all zeroes inside.
  26  */
  27
  28 class CCreateProcessHelper
  29 {
  30 public:
  31     static bool CreateProcess(LPCTSTR lpApplicationName,
  32                     LPTSTR lpCommandLine,
  33                     LPCTSTR lpCurrentDirectory,
  34                     LPPROCESS_INFORMATION lpProcessInformation);
  35     static bool CreateProcess(LPCTSTR lpApplicationName,
  36                     LPTSTR lpCommandLine,
  37                     LPPROCESS_INFORMATION lpProcessInformation);
  38
  39     static bool CreateProcessDetached(LPCTSTR lpApplicationName,
  40                     LPTSTR lpCommandLine,
  41                     LPCTSTR lpCurrentDirectory);
  42     static bool CreateProcessDetached(LPCTSTR lpApplicationName,
  43                     LPTSTR lpCommandLine);
  44     static bool CreateProcessDetached(LPCTSTR lpApplicationName, LPCTSTR lpCommandLine);
  45 };
  46
  47 inline bool CCreateProcessHelper::CreateProcess(LPCTSTR applicationName,
  48     LPTSTR commandLine, LPCTSTR currentDirectory,
  49     LPPROCESS_INFORMATION processInfo)
  50 {
  51         STARTUPINFO startupInfo = { 0 };
  52     startupInfo.cb = sizeof(STARTUPINFO);
  53
  54     memset(processInfo, 0, sizeof(PROCESS_INFORMATION));
  55     const BOOL result = ::CreateProcess(applicationName, commandLine, nullptr, nullptr, FALSE, CREATE_UNICODE_ENVIRONMENT, nullptr, currentDirectory, &startupInfo, processInfo);
  56     return result != 0;
  57 }
  58
  59 inline bool CCreateProcessHelper::CreateProcess(LPCTSTR applicationName,
  60     LPTSTR commandLine, LPPROCESS_INFORMATION processInformation)
  61 {
  62     return CreateProcess( applicationName, commandLine, nullptr, processInformation );
  63 }
  64
  65 inline bool CCreateProcessHelper::CreateProcessDetached(LPCTSTR lpApplicationName,
  66     LPTSTR lpCommandLine, LPCTSTR lpCurrentDirectory)
  67 {
  68     PROCESS_INFORMATION process;
  69     if (!CreateProcess(lpApplicationName, lpCommandLine, lpCurrentDirectory, &process))
  70         return false;
  71
  72     CloseHandle(process.hThread);
  73     CloseHandle(process.hProcess);
  74     return true;
  75 }
  76
  77 inline bool CCreateProcessHelper::CreateProcessDetached(LPCTSTR lpApplicationName,
  78     LPTSTR lpCommandLine)
  79 {
  80     return CreateProcessDetached(lpApplicationName, lpCommandLine, nullptr);
  81 }
  82
  83 inline bool CCreateProcessHelper::CreateProcessDetached(LPCTSTR lpApplicationName, LPCTSTR lpCommandLine)
  84 {
  85         // CreateProcess may modify buffer specified by lpCommandLine:
  86         // https://msdn.microsoft.com/en-us/library/windows/desktop/ms682425
  87         // [[
  88         // The Unicode version of this function, CreateProcessW, can modify
  89         // the contents of this string. Therefore, this parameter cannot be a
  90         // pointer to read - only memory(such as a const variable or a literal
  91         // string).If this parameter is a constant string, the function may
  92         // cause an access violation.
  93         // ]]
  94         LPWSTR commandLineBuf = nullptr;
  95         if (lpCommandLine)
  96                 commandLineBuf = _wcsdup(lpCommandLine);
  97         SCOPE_EXIT { free((void*)commandLineBuf); };
  98
  99         return CreateProcessDetached(lpApplicationName, commandLineBuf, nullptr);
 100 }