base/clipboard_util.cc

// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/clipboard_util.h"

#include <shellapi.h>
#include <shlwapi.h>
#include <wininet.h>

#include "base/basictypes.h"
#include "base/logging.h"
#include "base/scoped_handle.h"
#include "base/string_util.h"

namespace {

bool GetUrlFromHDrop(IDataObject* data_object, std::wstring* url,
                     std::wstring* title) {
  DCHECK(data_object && url && title);

  STGMEDIUM medium;
  if (FAILED(data_object->GetData(ClipboardUtil::GetCFHDropFormat(), &medium)))
    return false;

  HDROP hdrop = static_cast<HDROP>(GlobalLock(medium.hGlobal));

  if (!hdrop)
    return false;

  bool success = false;
  wchar_t filename[MAX_PATH];
  if (DragQueryFileW(hdrop, 0, filename, arraysize(filename))) {
    wchar_t url_buffer[INTERNET_MAX_URL_LENGTH];
    if (0 == _wcsicmp(PathFindExtensionW(filename), L".url") &&
        GetPrivateProfileStringW(L"InternetShortcut", L"url", 0, url_buffer,
                                 arraysize(url_buffer), filename)) {
      *url = url_buffer;
      PathRemoveExtension(filename);
      title->assign(PathFindFileName(filename));
      success = true;
    }
  }

  DragFinish(hdrop);
  GlobalUnlock(medium.hGlobal);
  // We don't need to call ReleaseStgMedium here because as far as I can tell,
  // DragFinish frees the hGlobal for us.
  return success;
}

bool SplitUrlAndTitle(const std::wstring& str, std::wstring* url,
    std::wstring* title) {
  DCHECK(url && title);
  size_t newline_pos = str.find('\n');
  bool success = false;
  if (newline_pos != std::string::npos) {
    *url = str.substr(0, newline_pos);
    title->assign(str.substr(newline_pos + 1));
    success = true;
  } else {
    *url = str;
    title->assign(str);
    success = true;
  }
  return success;
}

}  // namespace


FORMATETC* ClipboardUtil::GetUrlFormat() {
  static UINT cf = RegisterClipboardFormat(CFSTR_INETURLA);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetUrlWFormat() {
  static UINT cf = RegisterClipboardFormat(CFSTR_INETURLW);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetMozUrlFormat() {
  // The format is "URL\nTitle"
  static UINT cf = RegisterClipboardFormat(L"text/x-moz-url");
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetPlainTextFormat() {
  // We don't need to register this format since it's a built in format.
  static FORMATETC format = {CF_TEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetPlainTextWFormat() {
  // We don't need to register this format since it's a built in format.
  static FORMATETC format = {CF_UNICODETEXT, 0, DVASPECT_CONTENT, -1,
                             TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetFilenameWFormat() {
  static UINT cf = RegisterClipboardFormat(CFSTR_FILENAMEW);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetFilenameFormat()
{
  static UINT cf = RegisterClipboardFormat(CFSTR_FILENAMEA);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetHtmlFormat() {
  static UINT cf = RegisterClipboardFormat(L"HTML Format");
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetTextHtmlFormat() {
  static UINT cf = RegisterClipboardFormat(L"text/html");
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetCFHDropFormat() {
  // We don't need to register this format since it's a built in format.
  static FORMATETC format = {CF_HDROP, 0, DVASPECT_CONTENT, -1,
                             TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetFileDescriptorFormat() {
  static UINT cf = RegisterClipboardFormat(CFSTR_FILEDESCRIPTOR);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetFileContentFormatZero() {
  static UINT cf = RegisterClipboardFormat(CFSTR_FILECONTENTS);
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, 0, TYMED_HGLOBAL};
  return &format;
}

FORMATETC* ClipboardUtil::GetWebKitSmartPasteFormat() {
  static UINT cf = RegisterClipboardFormat(L"WebKit Smart Paste Format");
  static FORMATETC format = {cf, 0, DVASPECT_CONTENT, 0, TYMED_HGLOBAL};
  return &format;
}


bool ClipboardUtil::HasUrl(IDataObject* data_object) {
  DCHECK(data_object);
  return SUCCEEDED(data_object->QueryGetData(GetMozUrlFormat())) ||
      SUCCEEDED(data_object->QueryGetData(GetUrlWFormat())) ||
      SUCCEEDED(data_object->QueryGetData(GetUrlFormat())) ||
      SUCCEEDED(data_object->QueryGetData(GetFilenameWFormat())) ||
      SUCCEEDED(data_object->QueryGetData(GetFilenameFormat()));
}

bool ClipboardUtil::HasFilenames(IDataObject* data_object) {
  DCHECK(data_object);
  return SUCCEEDED(data_object->QueryGetData(GetCFHDropFormat()));
}

bool ClipboardUtil::HasPlainText(IDataObject* data_object) {
  DCHECK(data_object);
  return SUCCEEDED(data_object->QueryGetData(GetPlainTextWFormat())) ||
      SUCCEEDED(data_object->QueryGetData(GetPlainTextFormat()));
}


bool ClipboardUtil::GetUrl(IDataObject* data_object,
    std::wstring* url, std::wstring* title) {
  DCHECK(data_object && url && title);
  if (!HasUrl(data_object))
    return false;

  // Try to extract a URL from |data_object| in a variety of formats.
  STGMEDIUM store;
  if (GetUrlFromHDrop(data_object, url, title)) {
    return true;
  }

  if (SUCCEEDED(data_object->GetData(GetMozUrlFormat(), &store)) ||
      SUCCEEDED(data_object->GetData(GetUrlWFormat(), &store))) {
    // Mozilla URL format or unicode URL
    ScopedHGlobal<wchar_t> data(store.hGlobal);
    bool success = SplitUrlAndTitle(data.get(), url, title);
    ReleaseStgMedium(&store);
    if (success)
      return true;
  }

  if (SUCCEEDED(data_object->GetData(GetUrlFormat(), &store))) {
    // URL using ascii
    ScopedHGlobal<char> data(store.hGlobal);
    bool success = SplitUrlAndTitle(UTF8ToWide(data.get()), url, title);
    ReleaseStgMedium(&store);
    if (success)
      return true;
  }

  if (SUCCEEDED(data_object->GetData(GetFilenameWFormat(), &store))) {
    // filename using unicode
    ScopedHGlobal<wchar_t> data(store.hGlobal);
    bool success = false;
    if (data.get() && data.get()[0] && (PathFileExists(data.get()) ||
                                        PathIsUNC(data.get()))) {
      wchar_t file_url[INTERNET_MAX_URL_LENGTH];
      DWORD file_url_len = sizeof(file_url) / sizeof(file_url[0]);
      if (SUCCEEDED(::UrlCreateFromPathW(data.get(), file_url, &file_url_len,
                                         0))) {
        *url = file_url;
        title->assign(file_url);
        success = true;
      }
    }
    ReleaseStgMedium(&store);
    if (success)
      return true;
  }

  if (SUCCEEDED(data_object->GetData(GetFilenameFormat(), &store))) {
    // filename using ascii
    ScopedHGlobal<char> data(store.hGlobal);
    bool success = false;
    if (data.get() && data.get()[0] && (PathFileExistsA(data.get()) ||
                                        PathIsUNCA(data.get()))) {
      char file_url[INTERNET_MAX_URL_LENGTH];
      DWORD file_url_len = sizeof(file_url) / sizeof(file_url[0]);
      if (SUCCEEDED(::UrlCreateFromPathA(data.get(),
                                         file_url,
                                         &file_url_len,
                                         0))) {
        *url = UTF8ToWide(file_url);
        title->assign(*url);
        success = true;
      }
    }
    ReleaseStgMedium(&store);
    if (success)
      return true;
  }

  return false;
}

bool ClipboardUtil::GetFilenames(IDataObject* data_object,
                                 std::vector<std::wstring>* filenames) {
  DCHECK(data_object && filenames);
  if (!HasFilenames(data_object))
    return false;

  STGMEDIUM medium;
  if (FAILED(data_object->GetData(GetCFHDropFormat(), &medium)))
    return false;

  HDROP hdrop = static_cast<HDROP>(GlobalLock(medium.hGlobal));
  if (!hdrop)
    return false;

  const int kMaxFilenameLen = 4096;
  const unsigned num_files = DragQueryFileW(hdrop, 0xffffffff, 0, 0);
  for (unsigned int i = 0; i < num_files; ++i) {
    wchar_t filename[kMaxFilenameLen];
    if (!DragQueryFileW(hdrop, i, filename, kMaxFilenameLen))
      continue;
    filenames->push_back(filename);
  }

  DragFinish(hdrop);
  GlobalUnlock(medium.hGlobal);
  // We don't need to call ReleaseStgMedium here because as far as I can tell,
  // DragFinish frees the hGlobal for us.
  return true;
}

bool ClipboardUtil::GetPlainText(IDataObject* data_object,
                                 std::wstring* plain_text) {
  DCHECK(data_object && plain_text);
  if (!HasPlainText(data_object))
    return false;

  STGMEDIUM store;
  bool success = false;
  if (SUCCEEDED(data_object->GetData(GetPlainTextWFormat(), &store))) {
    // Unicode text
    ScopedHGlobal<wchar_t> data(store.hGlobal);
    plain_text->assign(data.get());
    ReleaseStgMedium(&store);
    success = true;
  } else if (SUCCEEDED(data_object->GetData(GetPlainTextFormat(), &store))) {
    // ascii text
    ScopedHGlobal<char> data(store.hGlobal);
    plain_text->assign(UTF8ToWide(data.get()));
    ReleaseStgMedium(&store);
    success = true;
  } else {
    //If a file is dropped on the window, it does not provide either of the
    //plain text formats, so here we try to forcibly get a url.
    std::wstring title;
    success = GetUrl(data_object, plain_text, &title);
  }

  return success;
}

bool ClipboardUtil::GetHtml(IDataObject* data_object,
                            std::wstring* html, std::string* base_url) {
  DCHECK(data_object && html && base_url);

  if (SUCCEEDED(data_object->QueryGetData(GetHtmlFormat()))) {
    STGMEDIUM store;
    if (SUCCEEDED(data_object->GetData(GetHtmlFormat(), &store))) {
      // MS CF html
      ScopedHGlobal<char> data(store.hGlobal);

      std::string html_utf8;
      CFHtmlToHtml(std::string(data.get(), data.Size()), &html_utf8, base_url);
      html->assign(UTF8ToWide(html_utf8));

      ReleaseStgMedium(&store);
      return true;
    }
  }

  if (FAILED(data_object->QueryGetData(GetTextHtmlFormat())))
    return false;

  STGMEDIUM store;
  if (FAILED(data_object->GetData(GetTextHtmlFormat(), &store)))
    return false;

  // text/html
  ScopedHGlobal<wchar_t> data(store.hGlobal);
  html->assign(data.get());
  ReleaseStgMedium(&store);
  return true;
}

bool ClipboardUtil::GetFileContents(IDataObject* data_object,
    std::wstring* filename, std::string* file_contents) {
  DCHECK(data_object && filename && file_contents);
  bool has_data =
      SUCCEEDED(data_object->QueryGetData(GetFileContentFormatZero())) ||
      SUCCEEDED(data_object->QueryGetData(GetFileDescriptorFormat()));

  if (!has_data)
    return false;

  STGMEDIUM content;
  // The call to GetData can be very slow depending on what is in
  // |data_object|.
  if (SUCCEEDED(data_object->GetData(GetFileContentFormatZero(), &content))) {
    if (TYMED_HGLOBAL == content.tymed) {
      ScopedHGlobal<char> data(content.hGlobal);
      file_contents->assign(data.get(), data.Size());
    }
    ReleaseStgMedium(&content);
  }

  STGMEDIUM description;
  if (SUCCEEDED(data_object->GetData(GetFileDescriptorFormat(),
                                     &description))) {
    ScopedHGlobal<FILEGROUPDESCRIPTOR> fgd(description.hGlobal);
    // We expect there to be at least one file in here.
    DCHECK(fgd->cItems >= 1);
    filename->assign(fgd->fgd[0].cFileName);
    ReleaseStgMedium(&description);
  }
  return true;
}

// HtmlToCFHtml and CFHtmlToHtml are based on similar methods in
// WebCore/platform/win/ClipboardUtilitiesWin.cpp.
/*
 * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

// Helper method for converting from text/html to MS CF_HTML.
// Documentation for the CF_HTML format is available at
// http://msdn.microsoft.com/en-us/library/aa767917(VS.85).aspx
std::string ClipboardUtil::HtmlToCFHtml(const std::string& html,
                                        const std::string& base_url) {
  if (html.empty())
    return std::string();

  #define MAX_DIGITS 10
  #define MAKE_NUMBER_FORMAT_1(digits) MAKE_NUMBER_FORMAT_2(digits)
  #define MAKE_NUMBER_FORMAT_2(digits) "%0" #digits "u"
  #define NUMBER_FORMAT MAKE_NUMBER_FORMAT_1(MAX_DIGITS)

  static const char* header = "Version:0.9\r\n"
      "StartHTML:" NUMBER_FORMAT "\r\n"
      "EndHTML:" NUMBER_FORMAT "\r\n"
      "StartFragment:" NUMBER_FORMAT "\r\n"
      "EndFragment:" NUMBER_FORMAT "\r\n";
  static const char* source_url_prefix = "SourceURL:";

  static const char* start_markup =
      "<html>\r\n<body>\r\n<!--StartFragment-->\r\n";
  static const char* end_markup =
      "\r\n<!--EndFragment-->\r\n</body>\r\n</html>";

  // Calculate offsets
  size_t start_html_offset = strlen(header) - strlen(NUMBER_FORMAT) * 4 +
      MAX_DIGITS * 4;
  if (!base_url.empty()) {
    start_html_offset += strlen(source_url_prefix) +
        base_url.length() + 2;  // Add 2 for \r\n.
  }
  size_t start_fragment_offset = start_html_offset + strlen(start_markup);
  size_t end_fragment_offset = start_fragment_offset + html.length();
  size_t end_html_offset = end_fragment_offset + strlen(end_markup);

  std::string result = StringPrintf(header, start_html_offset,
      end_html_offset, start_fragment_offset, end_fragment_offset);
  if (!base_url.empty()) {
    result.append(source_url_prefix);
    result.append(base_url);
    result.append("\r\n");
  }
  result.append(start_markup);
  result.append(html);
  result.append(end_markup);

  #undef MAX_DIGITS
  #undef MAKE_NUMBER_FORMAT_1
  #undef MAKE_NUMBER_FORMAT_2
  #undef NUMBER_FORMAT

  return result;
}

// Helper method for converting from MS CF_HTML to text/html.
void ClipboardUtil::CFHtmlToHtml(const std::string& cf_html,
                                 std::string* html,
                                 std::string* base_url) {
  // Obtain base_url if present.
  static std::string src_url_str("SourceURL:");
  size_t line_start = cf_html.find(src_url_str);
  if (line_start != std::string::npos) {
    size_t src_end = cf_html.find("\n", line_start);
    size_t src_start = line_start + src_url_str.length();
    if (src_end != std::string::npos && src_start != std::string::npos) {
      *base_url = cf_html.substr(src_start, src_end - src_start);
      TrimWhitespace(*base_url, TRIM_ALL, base_url);
    }
  }

  // Find the markup between "<!--StartFragment -->" and "<!--EndFragment-->".
  std::string cf_html_lower = StringToLowerASCII(cf_html);
  size_t markup_start = cf_html_lower.find("<html", 0);
  size_t tag_start = cf_html.find("StartFragment", markup_start);
  size_t fragment_start = cf_html.find('>', tag_start) + 1;
  size_t tag_end = cf_html.rfind("EndFragment", std::string::npos);
  size_t fragment_end = cf_html.rfind('<', tag_end);
  if (fragment_start != std::string::npos &&
      fragment_end != std::string::npos) {
    *html = cf_html.substr(fragment_start, fragment_end - fragment_start);
    TrimWhitespace(*html, TRIM_ALL, html);
  }
}