如何在C或C ++中包装参数并将其传递给系统或exec *

Question

我想写一个包装器，用argv做一些简单的事情并调用一些脚本。我有以下要求：

• 包装器必须是.exe文件
• 包装程序必须能够正确处理空格和引号
• 包装器将在用户端生成
• 生成过程必须很小（例如使用https://bellard.org/tcc）

我最初的方法：

编写c程序首先清除参数，然后将其用引号引起来，然后调用system。不幸的是，我无法从system或exec*函数获得结构良好的行为。我希望以下所有示例输出类似arg1=1; arg2=2; arg3=3; arg4=的内容（在引号中有一些差异），但是在某些示例中它会出错，并在execl处暂停：

输入文件：

@:: test.bat
@echo off

echo arg1=%1; arg2=%2; arg3=%3; arg4=%4

//minimal-example.c
#include <Windows.h>
#include <stdio.h>

int main( int argc, char ** argv ) {
  puts("\nExample 1:");
  system("\"test.bat\" \"1\" \"2\" \"3\" ");

  puts("\nExample 2:");
  system("test.bat \"1\" \"2\" \"3\" ");

  puts("\nExample 3:");
  system("test.bat 1 2 \"3\" ");

  puts("\nExample 4:");
  system("\"test.bat\" 1 \"2\" 3 ");

  puts("\nExample 5:");
  system("\"test.bat\" 1 2 3 ");

  puts("\nExample 6:");
  execl(argv[0], "test.bat", "1", "2", "3", NULL);

  return 0;
}

输出运行：

Example 1:
'test.bat" "1" "2" "3' is not recognized as an internal or external command,
operable program or batch file.

Example 2:
arg1="1"; arg2="2"; arg3="3"; arg4=

Example 3:
arg1=1; arg2=2; arg3="3"; arg4=

Example 4:
'test.bat" 1 "2' is not recognized as an internal or external command,
operable program or batch file.

Example 5:
arg1=1; arg2=2; arg3=3; arg4=

Example 6:
arg1=1; arg2=2; arg3=3; arg4=

（示例6暂停，直到按下Enter为止]

问题：

1. 是否存在以system中允许空格的方式正确包装路径/参数的方法？
2. 我可以在system的参数中转义引号吗？
3. 是否有运行exec*的非阻塞方式？
4. exec*方法是否可以确保包装程序的stdin stdout和stderr行为正确（没有奇怪的溢出或奇怪的阻塞现象？）

Answer 1

类似这样的方法应该起作用：

 string cmd = "test.bat";

 for(int i = 1; i < argc; i++) {
    cmd += " ";
    cmd += argv[i]
 }

 system(cmd.c_str());

当然，其中包含空格的args需要通过添加引号进行进一步处理，带有引号的参数可能需要转义，并且在args包含无法直接处理的内容的情况下，还需要进行许多其他复杂处理）

作为替代，您可以看看Use CreateProcess to Run a Batch File

Answer 2

实施

我最终为两种不同的情况编写了两个包装：一个用于保持终端窗口打开，另一个用于无提示运行。

通过将exe文件重命名为name-of-script.exe，然后包装程序将尝试运行<exedir>\bin\name-of-script.bat并传递所有命令行参数。

我使用程序Resource Hacker在exe中放置漂亮的图标或版本信息，使其看起来像是正确的程序。

代码

tcc.exe -D_UNICODE -DNOSHELL launcher.c -luser32 -lkernel32 -mwindows -o launcher-noshell.exe
tcc.exe -D_UNICODE launcher.c -luser32 -lkernel32 -o launcher.exe

#define _WIN32_WINNT 0x0500
#include <windows.h>
#include <stdbool.h>
#include <tchar.h>

#ifdef NOSHELL
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
#else
int main( int argc, char ** argv ) 
#endif
{
    //*******************************************
    //Get commanline string as a whole
    //*******************************************
    TCHAR* cmdArgs = GetCommandLineW();
    TCHAR* cmdPath;
    cmdPath = (TCHAR*) malloc((_tcslen(cmdArgs)+1)*2);
    _tcscpy(cmdPath, cmdArgs);


    //*******************************************
    //Split filepath, filename, and commandline
    //*******************************************
    bool inQuote = false;
    bool isArgs = false;
    int j = 0;

    for(int i=0; i<_tcslen(cmdArgs)+1; i++){
      //must be easier way to index unicode string
      TCHAR c = *(TCHAR *)(&cmdArgs[i*2]);

      if(c == L'"'){inQuote = !inQuote;}
      if(c == L' ' && !inQuote){ isArgs = true;}

      if(isArgs){
        cmdPath[i*2]   = '\0';
        cmdPath[i*2+1] = '\0';
      }

      //do for both unicode bits
      cmdArgs[j*2  ] = cmdArgs[i*2  ];
      cmdArgs[j*2+1] = cmdArgs[i*2+1];

      //sync j with i after filepath
      if(isArgs){ j++; }
    }


    //*******************************************
    //Remove quotes around filepath
    //*******************************************
    if(*(TCHAR *)(&cmdPath[0]) == L'"'){
      cmdPath = &cmdPath[2];
    }
    int cmdPathEnd = _tcslen(cmdPath);
    if(*(TCHAR *)(&cmdPath[(cmdPathEnd-1)*2]) == L'"'){
      cmdPath[(cmdPathEnd-1)*2]='\0';
      cmdPath[(cmdPathEnd-1)*2+1]='\0';
    }


    //*******************************************
    //Find basedir of cmdPath
    //*******************************************
    TCHAR* cmdBaseDir;
    cmdBaseDir = (TCHAR*) malloc((_tcslen(cmdPath)+1)*2);
    _tcscpy(cmdBaseDir, cmdPath);


    int nrOfSlashed = 0;
    int slashLoc = 0;
    for(int i=0; i<_tcslen(cmdBaseDir); i++){
      //must be easier way to index unicode string
      TCHAR c = *(TCHAR *)(&cmdBaseDir[i*2]);
      if(c == L'\\' || c == L'//'){
        nrOfSlashed+=1;
        slashLoc=i;
      }
    }

    if(nrOfSlashed==0){
      _tcscpy(cmdBaseDir, L".");
    }else{
      cmdBaseDir[2*slashLoc] = '\0';
      cmdBaseDir[2*slashLoc+1] = '\0';  
    }


    //*******************************************
    //Find filename without .exe
    //*******************************************
    TCHAR* cmdName;
    cmdName = (TCHAR*) malloc((_tcslen(cmdPath)+1)*2);
    _tcscpy(cmdName, cmdPath);

    cmdName = &cmdPath[slashLoc==0?0:slashLoc*2+2];
    int fnameend = _tcslen(cmdName);
    if(0 < fnameend-4){
        cmdName[(fnameend-4)*2]   = '\0';
        cmdName[(fnameend-4)*2+1] = '\0';
    }

    //_tprintf(L"%s\n", cmdName);

    //********************************************
    //Bat name to be checked
    //********************************************
    int totlen;

    TCHAR* batFile1  = cmdBaseDir;
    TCHAR* batFile2  = L"\\bin\\";
    TCHAR* batFile3  = cmdName;
    TCHAR* batFile4  = L".bat";

    totlen = (_tcslen(batFile1)+ _tcslen(batFile2)+ _tcslen(batFile3)+ _tcslen(batFile4));

    TCHAR* batFile;
    batFile = (TCHAR*) malloc((totlen+1)*2);
    _tcscpy(batFile, batFile1);
    _tcscat(batFile, batFile2);
    _tcscat(batFile, batFile3);
    _tcscat(batFile, batFile4);

    if(0 != _waccess(batFile, 0)){
        system("powershell -command \"[reflection.assembly]::LoadWithPartialName('System.Windows.Forms')|out-null;[windows.forms.messagebox]::Show('Could not find the launcher .bat in bin directory.', 'Execution error')\" ");
    };

    //_tprintf(L"%s\n", batFile);

    //*******************************************
    //Get into this form: cmd.exe /c ""c:\path\...bat" arg1 arg2 ... "
    //*******************************************
    TCHAR* cmdLine1  = L"cmd.exe /c \"";
    TCHAR* cmdLine2  = L"\"";
    TCHAR* cmdLine3  = batFile;
    TCHAR* cmdLine4  = L"\" "; 
    TCHAR* cmdLine5  = cmdArgs;
    TCHAR* cmdLine6 = L"\"";

    totlen = (_tcslen(cmdLine1)+_tcslen(cmdLine2)+_tcslen(cmdLine3)+_tcslen(cmdLine4)+_tcslen(cmdLine5)+_tcslen(cmdLine6));

    TCHAR* cmdLine;
    cmdLine = (TCHAR*) malloc((totlen+1)*2);

    _tcscpy(cmdLine, cmdLine1);
    _tcscat(cmdLine, cmdLine2);
    _tcscat(cmdLine, cmdLine3);
    _tcscat(cmdLine, cmdLine4);
    _tcscat(cmdLine, cmdLine5);
    _tcscat(cmdLine, cmdLine6);

    //_tprintf(L"%s\n", cmdLine);

    //************************************
    //Prepare and run CreateProcessW
    //************************************
    PROCESS_INFORMATION pi;
    STARTUPINFO si;

    memset(&si, 0, sizeof(si));
    si.cb = sizeof(si);

    #ifdef NOSHELL
    CreateProcessW(NULL, cmdLine, NULL, NULL, TRUE, CREATE_NO_WINDOW, NULL, NULL, &si, &pi);
    #else
    CreateProcessW(NULL, cmdLine, NULL, NULL, TRUE, NULL,             NULL, NULL, &si, &pi);
    #endif

    //************************************
    //Return ErrorLevel
    //************************************
    DWORD result = WaitForSingleObject(pi.hProcess,15000);

    if(result == WAIT_TIMEOUT){return -2;} //Timeout error

    DWORD exitCode=0;
    if(!GetExitCodeProcess(pi.hProcess, &exitCode) ){return -1;} //Cannot get exitcode

    return exitCode; //Correct exitcode
}