deskflow/src/lib/platform/MSWindowsClipboardBitmapConverter.cpp

/*
 * Deskflow -- mouse and keyboard sharing utility
 * Copyright (C) 2012-2016 Symless Ltd.
 * Copyright (C) 2004 Chris Schoeneman
 *
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file LICENSE that should have accompanied this file.
 *
 * This package is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "platform/MSWindowsClipboardBitmapConverter.h"

#include "base/Log.h"

//
// MSWindowsClipboardBitmapConverter
//

MSWindowsClipboardBitmapConverter::MSWindowsClipboardBitmapConverter() {
  // do nothing
}

MSWindowsClipboardBitmapConverter::~MSWindowsClipboardBitmapConverter() {
  // do nothing
}

IClipboard::EFormat MSWindowsClipboardBitmapConverter::getFormat() const {
  return IClipboard::kBitmap;
}

UINT MSWindowsClipboardBitmapConverter::getWin32Format() const {
  return CF_DIB;
}

HANDLE
MSWindowsClipboardBitmapConverter::fromIClipboard(const String &data) const {
  // copy to memory handle
  HGLOBAL gData = GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE, data.size());
  if (gData != NULL) {
    // get a pointer to the allocated memory
    char *dst = (char *)GlobalLock(gData);
    if (dst != NULL) {
      memcpy(dst, data.data(), data.size());
      GlobalUnlock(gData);
    } else {
      GlobalFree(gData);
      gData = NULL;
    }
  }

  return gData;
}

String MSWindowsClipboardBitmapConverter::toIClipboard(HANDLE data) const {
  // get datator
  LPVOID src = GlobalLock(data);
  if (src == NULL) {
    return String();
  }
  UInt32 srcSize = (UInt32)GlobalSize(data);

  // check image type
  const BITMAPINFO *bitmap = static_cast<const BITMAPINFO *>(src);
  LOG(
      (CLOG_INFO "bitmap: %dx%d %d", bitmap->bmiHeader.biWidth,
       bitmap->bmiHeader.biHeight, (int)bitmap->bmiHeader.biBitCount));
  if (bitmap->bmiHeader.biPlanes == 1 &&
      (bitmap->bmiHeader.biBitCount == 24 ||
       bitmap->bmiHeader.biBitCount == 32) &&
      bitmap->bmiHeader.biCompression == BI_RGB) {
    // already in canonical form
    String image(static_cast<char const *>(src), srcSize);
    GlobalUnlock(data);
    return image;
  }

  // create a destination DIB section
  LOG(
      (CLOG_INFO "convert image from: depth=%d comp=%d",
       bitmap->bmiHeader.biBitCount, bitmap->bmiHeader.biCompression));
  void *raw;
  BITMAPINFOHEADER info;
  LONG w = bitmap->bmiHeader.biWidth;
  LONG h = bitmap->bmiHeader.biHeight;
  info.biSize = sizeof(BITMAPINFOHEADER);
  info.biWidth = w;
  info.biHeight = h;
  info.biPlanes = 1;
  info.biBitCount = 32;
  info.biCompression = BI_RGB;
  info.biSizeImage = 0;
  info.biXPelsPerMeter = 1000;
  info.biYPelsPerMeter = 1000;
  info.biClrUsed = 0;
  info.biClrImportant = 0;
  HDC dc = GetDC(NULL);
  HBITMAP dst =
      CreateDIBSection(dc, (BITMAPINFO *)&info, DIB_RGB_COLORS, &raw, NULL, 0);

  // find the start of the pixel data
  const char *srcBits = (const char *)bitmap + bitmap->bmiHeader.biSize;
  if (bitmap->bmiHeader.biBitCount >= 16) {
    if (bitmap->bmiHeader.biCompression == BI_BITFIELDS &&
        (bitmap->bmiHeader.biBitCount == 16 ||
         bitmap->bmiHeader.biBitCount == 32)) {
      srcBits += 3 * sizeof(DWORD);
    }
  } else if (bitmap->bmiHeader.biClrUsed != 0) {
    srcBits += bitmap->bmiHeader.biClrUsed * sizeof(RGBQUAD);
  } else {
    // http://msdn.microsoft.com/en-us/library/ke55d167(VS.80).aspx
    srcBits += (1i64 << bitmap->bmiHeader.biBitCount) * sizeof(RGBQUAD);
  }

  // copy source image to destination image
  HDC dstDC = CreateCompatibleDC(dc);
  HGDIOBJ oldBitmap = SelectObject(dstDC, dst);
  SetDIBitsToDevice(
      dstDC, 0, 0, w, h, 0, 0, 0, h, srcBits, bitmap, DIB_RGB_COLORS);
  SelectObject(dstDC, oldBitmap);
  DeleteDC(dstDC);
  GdiFlush();

  // extract data
  String image((const char *)&info, info.biSize);
  image.append((const char *)raw, 4 * w * h);

  // clean up GDI
  DeleteObject(dst);
  ReleaseDC(NULL, dc);

  // release handle
  GlobalUnlock(data);

  return image;
}