xClip (Reverse Clip) for Windows - Simulate reverse process of the clip command on Windows

xclip.cpp

/**
 * xClip (Reverse Clip) for Windows
 * Author: Abhishek Bhattacharya <[email protected]>
 *
 * Build Environment:
 *   Windows 10 Version 1607 (Windows 7 or above should work fine)
 *   MinGW g++ (GCC) 5.3.0 or above (with flag --std=c++11)
 *   UPX x3.91 or above
 * Runtime Environment:
 *   Windows 7 or above
 * Build Commands:
 *   g++ -std=c++11 -Os -s xclip.cpp -o xclip.exe
 *   upx xclip.exe
 *
 * Usage: xclip [OPTION]
 * Redirects text contents of Windows Clipboard to the standard output.
 * This is essentially a "paste" replacement to the Windows CLIP command.
 *
 *   -h, --help          Displays this help message.
 *
 * Examples:
 *   xclip | type        View the text contents from Windows clipboard.
 *   xclip > readme.txt  Appends a copy of the text from Windows clipboard to the file readme.txt.
 */

//////////////////////////////////////
// xClip (Reverse Clip) for Windows //
//////////////////////////////////////

#include <windows.h>
#include <string>
#include <iostream>
using namespace std;

string getClipTextData();
inline bool isArgHelp(const char *arg);
void displayHelpContents();

int main(int argc, const char *argv[]) {
  if(argc > 1 && isArgHelp(argv[1])) {
    displayHelpContents();
    return 0;
  }

  cout << getClipTextData() << endl;
  return 0;
}

string getClipTextData() {
  if (!IsClipboardFormatAvailable(CF_TEXT))
    return string(); // error
  if(!OpenClipboard(nullptr))
    return string(); // error

  HANDLE hData = GetClipboardData(CF_TEXT);
  if(hData == nullptr)
    return string(); // error

  const char *ptrTxt = static_cast<const char *>(GlobalLock(hData));
  string retVal(ptrTxt);

  GlobalUnlock(hData);

  CloseClipboard();

  return retVal;
}

///////////
// Utils //
///////////

inline bool isArgHelp(const char *arg) {
  return (string(arg) == "-h" || string(arg) == "--help");
}

void displayHelpContents() {
  cout << "Usage: xclip [OPTION]"
          "\nRedirects text contents of Windows Clipboard to the standard output."
          "\nThis is essentially a \"paste\" replacement to the Windows CLIP command."
          "\n\n   -h, --help          Displays this help message."
          "\n\n Examples:"
          "\n   xclip | type        View the text contents from Windows clipboard."
          "\n   xclip > readme.txt  Appends a copy of the text from"
          "\n                       Windows clipboard to the file readme.txt."
          "\n\nCreated by Abhishek Bhattacharya. Report issues to: <[email protected]>"
          "\nLicensed under The MIT License (MIT). More information at: <https://opensource.org/licenses/MIT>";
}