Basic implementation of the clipboard on the Mac.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@717 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 658 insertions, 0 deletions

diff --git a/base/clipboard_win.cc b/base/clipboard_win.cc
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+++ b/base/clipboard_win.cc
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+// Copyright 2008, Google 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:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * 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.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "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 THE COPYRIGHT
+// OWNER 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.
+
+// Many of these functions are based on those found in
+// webkit/port/platform/PasteboardWin.cpp
+
+#include <shlobj.h>
+#include <shellapi.h>
+
+#include "base/clipboard.h"
+
+#include "base/clipboard_util.h"
+#include "base/logging.h"
+#include "base/string_util.h"
+
+namespace {
+
+// A small object to ensure we close the clipboard after opening it.
+class ClipboardLock {
+ public:
+  ClipboardLock() : we_own_the_lock_(false) { }
+
+  ~ClipboardLock() {
+    if (we_own_the_lock_)
+      Release();
+  }
+
+  bool Acquire(HWND owner) {
+    // We shouldn't be calling this if we already own the clipbard lock.
+    DCHECK(!we_own_the_lock_);
+
+    // We already have the lock.  We don't want to stomp on the other use.
+    if (we_own_the_lock_)
+      return false;
+
+    const int kMaxAttemptsToOpenClipboard = 5;
+
+    // Attempt to acquire the clipboard lock.  This may fail if another process
+    // currently holds the lock.  We're willing to try a few times in the hopes
+    // of acquiring it.
+    //
+    // This turns out to be an issue when using remote desktop because the
+    // rdpclip.exe process likes to read what we've written to the clipboard and
+    // send it to the RDP client.  If we open and close the clipboard in quick
+    // succession, we might be trying to open it while rdpclip.exe has it open,
+    // See Bug 815425.
+    //
+    // In fact, we believe we'll only spin this loop over remote desktop.  In
+    // normal situations, the user is initiating clipboard operations and there
+    // shouldn't be lock contention.
+
+    for (int attempts = 0; attempts < kMaxAttemptsToOpenClipboard; ++attempts) {
+      if (::OpenClipboard(owner)) {
+        we_own_the_lock_ = true;
+        return we_own_the_lock_;
+      }
+
+      // Having failed, we yeild our timeslice to other processes. ::Yield seems
+      // to be insufficient here, so we sleep for 5 ms.
+      if (attempts < (kMaxAttemptsToOpenClipboard - 1))
+        ::Sleep(5);
+    }
+
+    // We failed to acquire the clipboard.
+    return false;
+  }
+
+  void Release() {
+    // We should only be calling this if we already own the clipbard lock.
+    DCHECK(we_own_the_lock_);
+
+    // We we don't have the lock, there is nothing to release.
+    if (!we_own_the_lock_)
+      return;
+
+    ::CloseClipboard();
+    we_own_the_lock_ = false;
+  }
+
+ private:
+  bool we_own_the_lock_;
+};
+
+LRESULT CALLBACK ClipboardOwnerWndProc(HWND hwnd,
+                                       UINT message,
+                                       WPARAM wparam,
+                                       LPARAM lparam) {
+  LRESULT lresult = 0;
+
+  switch(message) {
+  case WM_RENDERFORMAT:
+    // This message comes when SetClipboardData was sent a null data handle
+    // and now it's come time to put the data on the clipboard.
+    // We always set data, so there isn't a need to actually do anything here.
+    break;
+  case WM_RENDERALLFORMATS:
+    // This message comes when SetClipboardData was sent a null data handle
+    // and now this application is about to quit, so it must put data on
+    // the clipboard before it exits.
+    // We always set data, so there isn't a need to actually do anything here.
+    break;
+  case WM_DRAWCLIPBOARD:
+    break;
+  case WM_DESTROY:
+    break;
+  case WM_CHANGECBCHAIN:
+    break;
+  default:
+    lresult = DefWindowProc(hwnd, message, wparam, lparam);
+    break;
+  }
+  return lresult;
+}
+
+template <typename charT>
+HGLOBAL CreateGlobalData(const std::basic_string<charT>& str) {
+  HGLOBAL data =
+    ::GlobalAlloc(GMEM_MOVEABLE, ((str.size() + 1) * sizeof(charT)));
+  if (data) {
+    charT* raw_data = static_cast<charT*>(::GlobalLock(data));
+    memcpy(raw_data, str.data(), str.size() * sizeof(charT));
+    raw_data[str.size()] = '\0';
+    ::GlobalUnlock(data);
+  }
+  return data;
+};
+
+} // namespace
+
+Clipboard::Clipboard() {
+  // make a dummy HWND to be the clipboard's owner
+  WNDCLASSEX wcex = {0};
+  wcex.cbSize = sizeof(WNDCLASSEX);
+  wcex.lpfnWndProc = ClipboardOwnerWndProc;
+  wcex.hInstance = GetModuleHandle(NULL);
+  wcex.lpszClassName = L"ClipboardOwnerWindowClass";
+  ::RegisterClassEx(&wcex);
+
+  clipboard_owner_ = ::CreateWindow(L"ClipboardOwnerWindowClass",
+                                    L"ClipboardOwnerWindow",
+                                    0, 0, 0, 0, 0,
+                                    HWND_MESSAGE,
+                                    0, 0, 0);
+}
+
+Clipboard::~Clipboard() {
+  ::DestroyWindow(clipboard_owner_);
+  clipboard_owner_ = NULL;
+}
+
+void Clipboard::Clear() {
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  ::EmptyClipboard();
+}
+
+void Clipboard::WriteText(const std::wstring& text) {
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HGLOBAL glob = CreateGlobalData(text);
+  if (glob && !::SetClipboardData(CF_UNICODETEXT, glob))
+    ::GlobalFree(glob);
+}
+
+void Clipboard::WriteHTML(const std::wstring& markup,
+                          const std::string& url) {
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  std::string html_fragment;
+  MarkupToHTMLClipboardFormat(markup, url, &html_fragment);
+  HGLOBAL glob = CreateGlobalData(html_fragment);
+  if (glob && !::SetClipboardData(ClipboardUtil::GetHtmlFormat()->cfFormat,
+                                  glob)) {
+    ::GlobalFree(glob);
+  }
+}
+
+void Clipboard::WriteBookmark(const std::wstring& title,
+                              const std::string& url) {
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  std::wstring bookmark(title);
+  bookmark.append(1, L'\n');
+  bookmark.append(UTF8ToWide(url));
+  HGLOBAL glob = CreateGlobalData(bookmark);
+  if (glob && !::SetClipboardData(ClipboardUtil::GetUrlWFormat()->cfFormat,
+                                  glob)) {
+    ::GlobalFree(glob);
+  }
+}
+
+void Clipboard::WriteHyperlink(const std::wstring& title,
+                               const std::string& url) {
+  // Write as a bookmark.
+  WriteBookmark(title, url);
+
+  // Build the HTML link.
+  std::wstring link(L"<a href=\"");
+  link.append(UTF8ToWide(url));
+  link.append(L"\">");
+  link.append(title);
+  link.append(L"</a>");
+
+  // Write as an HTML link.
+  WriteHTML(link, std::string());
+}
+
+void Clipboard::WriteWebSmartPaste() {
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  SetClipboardData(ClipboardUtil::GetWebKitSmartPasteFormat()->cfFormat, NULL);
+}
+
+void Clipboard::WriteBitmap(const void* pixels, const gfx::Size& size) {
+  HDC dc = ::GetDC(NULL);
+
+  // This doesn't actually cost us a memcpy when the bitmap comes from the
+  // renderer as we load it into the bitmap using setPixels which just sets a
+  // pointer.  Someone has to memcpy it into GDI, it might as well be us here.
+
+  // TODO(darin): share data in gfx/bitmap_header.cc somehow
+  BITMAPINFO bm_info = {0};
+  bm_info.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
+  bm_info.bmiHeader.biWidth = size.width();
+  bm_info.bmiHeader.biHeight = -size.height();  // sets vertical orientation
+  bm_info.bmiHeader.biPlanes = 1;
+  bm_info.bmiHeader.biBitCount = 32;
+  bm_info.bmiHeader.biCompression = BI_RGB;
+
+  // ::CreateDIBSection allocates memory for us to copy our bitmap into.
+  // Unfortunately, we can't write the created bitmap to the clipboard,
+  // (see http://msdn2.microsoft.com/en-us/library/ms532292.aspx)
+  void *bits;
+  HBITMAP source_hbitmap =
+      ::CreateDIBSection(dc, &bm_info, DIB_RGB_COLORS, &bits, NULL, 0);
+
+  if (bits && source_hbitmap) {
+    // Copy the bitmap out of shared memory and into GDI
+    memcpy(bits, pixels, 4 * size.width() * size.height());
+
+    // Now we have an HBITMAP, we can write it to the clipboard
+    WriteBitmapFromHandle(source_hbitmap, size);
+  }
+
+  ::DeleteObject(source_hbitmap);
+  ::ReleaseDC(NULL, dc);
+}
+
+void Clipboard::WriteBitmapFromSharedMemory(const SharedMemory& bitmap,
+                                            const gfx::Size& size) {
+  // TODO(darin): share data in gfx/bitmap_header.cc somehow
+  BITMAPINFO bm_info = {0};
+  bm_info.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
+  bm_info.bmiHeader.biWidth = size.width();
+  bm_info.bmiHeader.biHeight = -size.height();  // Sets the vertical orientation
+  bm_info.bmiHeader.biPlanes = 1;
+  bm_info.bmiHeader.biBitCount = 32;
+  bm_info.bmiHeader.biCompression = BI_RGB;
+
+  HDC dc = ::GetDC(NULL);
+
+  // We can create an HBITMAP directly using the shared memory handle, saving
+  // a memcpy.
+  HBITMAP source_hbitmap =
+      ::CreateDIBSection(dc, &bm_info, DIB_RGB_COLORS, NULL, bitmap.handle(), 0);
+
+  if (source_hbitmap) {
+    // Now we can write the HBITMAP to the clipboard
+    WriteBitmapFromHandle(source_hbitmap, size);
+  }
+
+  ::DeleteObject(source_hbitmap);
+  ::ReleaseDC(NULL, dc);
+}
+
+void Clipboard::WriteBitmapFromHandle(HBITMAP source_hbitmap,
+                                      const gfx::Size& size) {
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  // We would like to just call ::SetClipboardData on the source_hbitmap,
+  // but that bitmap might not be of a sort we can write to the clipboard.
+  // For this reason, we create a new bitmap, copy the bits over, and then
+  // write that to the clipboard.
+
+  HDC dc = ::GetDC(NULL);
+  HDC compatible_dc = ::CreateCompatibleDC(NULL);
+  HDC source_dc = ::CreateCompatibleDC(NULL);
+
+  // This is the HBITMAP we will eventually write to the clipboard
+  HBITMAP hbitmap = ::CreateCompatibleBitmap(dc, size.width(), size.height());
+  if (!hbitmap) {
+    // Failed to create the bitmap
+    ::DeleteDC(compatible_dc);
+    ::DeleteDC(source_dc);
+    ::ReleaseDC(NULL, dc);
+    return;
+  }
+
+  HBITMAP old_hbitmap = (HBITMAP)SelectObject(compatible_dc, hbitmap);
+  HBITMAP old_source = (HBITMAP)SelectObject(source_dc, source_hbitmap);
+
+  // Now we need to blend it into an HBITMAP we can place on the clipboard
+  BLENDFUNCTION bf = {AC_SRC_OVER, 0, 255, AC_SRC_ALPHA};
+  ::AlphaBlend(compatible_dc, 0, 0, size.width(), size.height(),
+               source_dc, 0, 0, size.width(), size.height(), bf);
+
+  // Clean up all the handles we just opened
+  ::SelectObject(compatible_dc, old_hbitmap);
+  ::SelectObject(source_dc, old_source);
+  ::DeleteObject(old_hbitmap);
+  ::DeleteObject(old_source);
+  ::DeleteDC(compatible_dc);
+  ::DeleteDC(source_dc);
+  ::ReleaseDC(NULL, dc);
+
+  // Actually write the bitmap to the clipboard
+  ::SetClipboardData(CF_BITMAP, hbitmap);
+}
+
+// Write a file or set of files to the clipboard in HDROP format. When the user
+// invokes a paste command (in a Windows explorer shell, for example), the files
+// will be copied to the paste location.
+void Clipboard::WriteFile(const std::wstring& file) {
+  std::vector<std::wstring> files;
+  files.push_back(file);
+  WriteFiles(files);
+}
+
+void Clipboard::WriteFiles(const std::vector<std::wstring>& files) {
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  // Calculate the amount of space we'll need store the strings: require
+  // NULL terminator between strings, and double null terminator at the end.
+  size_t bytes = sizeof(DROPFILES);
+  for (size_t i = 0; i < files.size(); ++i)
+    bytes += (files[i].length() + 1) * sizeof(wchar_t);
+  bytes += sizeof(wchar_t);
+
+  HANDLE hdata = ::GlobalAlloc(GMEM_MOVEABLE, bytes);
+  if (!hdata)
+    return;
+
+  DROPFILES* drop_files = static_cast<DROPFILES*>(::GlobalLock(hdata));
+  drop_files->pFiles = sizeof(DROPFILES);
+  drop_files->fWide = TRUE;
+  BYTE* data = reinterpret_cast<BYTE*>(drop_files) + sizeof(DROPFILES);
+
+  // Copy the strings stored in 'files' with proper NULL separation.
+  wchar_t* data_pos = reinterpret_cast<wchar_t*>(data);
+  for (size_t i = 0; i < files.size(); ++i) {
+    size_t offset = files[i].length() + 1;
+    memcpy(data_pos, files[i].c_str(), offset * sizeof(wchar_t));
+    data_pos += offset;
+  }
+  data_pos[0] = L'\0';  // Double NULL termination after the last string.
+
+  ::GlobalUnlock(hdata);
+  if (!::SetClipboardData(CF_HDROP, hdata))
+    ::GlobalFree(hdata);
+}
+
+bool Clipboard::IsFormatAvailable(unsigned int format) const {
+  return ::IsClipboardFormatAvailable(format) != FALSE;
+}
+
+void Clipboard::ReadText(std::wstring* result) const {
+  if (!result) {
+    NOTREACHED();
+    return;
+  }
+
+  result->clear();
+
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HANDLE data = ::GetClipboardData(CF_UNICODETEXT);
+  if (!data)
+    return;
+
+  result->assign(static_cast<const wchar_t*>(::GlobalLock(data)));
+  ::GlobalUnlock(data);
+}
+
+void Clipboard::ReadAsciiText(std::string* result) const {
+  if (!result) {
+    NOTREACHED();
+    return;
+  }
+
+  result->clear();
+
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HANDLE data = ::GetClipboardData(CF_TEXT);
+  if (!data)
+    return;
+
+  result->assign(static_cast<const char*>(::GlobalLock(data)));
+  ::GlobalUnlock(data);
+}
+
+void Clipboard::ReadHTML(std::wstring* markup, std::string* src_url) const {
+  if (markup)
+    markup->clear();
+
+  if (src_url)
+    src_url->clear();
+
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HANDLE data = ::GetClipboardData(ClipboardUtil::GetHtmlFormat()->cfFormat);
+  if (!data)
+    return;
+
+  std::string html_fragment(static_cast<const char*>(::GlobalLock(data)));
+  ::GlobalUnlock(data);
+
+  ParseHTMLClipboardFormat(html_fragment, markup, src_url);
+}
+
+void Clipboard::ReadBookmark(std::wstring* title, std::string* url) const {
+  if (title)
+    title->clear();
+
+  if (url)
+    url->clear();
+
+  // Acquire the clipboard.
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HANDLE data = ::GetClipboardData(ClipboardUtil::GetUrlWFormat()->cfFormat);
+  if (!data)
+    return;
+
+  std::wstring bookmark(static_cast<const wchar_t*>(::GlobalLock(data)));
+  ::GlobalUnlock(data);
+
+  ParseBookmarkClipboardFormat(bookmark, title, url);
+}
+
+// Read a file in HDROP format from the clipboard.
+void Clipboard::ReadFile(std::wstring* file) const {
+  if (!file) {
+    NOTREACHED();
+    return;
+  }
+
+  file->clear();
+  std::vector<std::wstring> files;
+  ReadFiles(&files);
+
+  // Take the first file, if available.
+  if (!files.empty())
+    file->assign(files[0]);
+}
+
+// Read a set of files in HDROP format from the clipboard.
+void Clipboard::ReadFiles(std::vector<std::wstring>* files) const {
+  if (!files) {
+    NOTREACHED();
+    return;
+  }
+
+  files->clear();
+
+  ClipboardLock lock;
+  if (!lock.Acquire(clipboard_owner_))
+    return;
+
+  HDROP drop = static_cast<HDROP>(::GetClipboardData(CF_HDROP));
+  if (!drop)
+    return;
+
+  // Count of files in the HDROP.
+  int count = ::DragQueryFile(drop, 0xffffffff, NULL, 0);
+
+  if (count) {
+    for (int i = 0; i < count; ++i) {
+      int size = ::DragQueryFile(drop, i, NULL, 0) + 1;
+      std::wstring file;
+      ::DragQueryFile(drop, i, WriteInto(&file, size), size);
+      files->push_back(file);
+    }
+  }
+}
+
+// static
+void Clipboard::MarkupToHTMLClipboardFormat(const std::wstring& markup,
+                                            const std::string& src_url,
+                                            std::string* html_fragment) {
+  DCHECK(html_fragment);
+  // Documentation for the CF_HTML format is available at
+  // http://msdn.microsoft.com/workshop/networking/clipboard/htmlclipboard.asp
+
+  if (markup.empty()) {
+    html_fragment->clear();
+    return;
+  }
+
+  std::string markup_utf8 = WideToUTF8(markup);
+
+  html_fragment->assign("Version:0.9");
+
+  std::string start_html("\nStartHTML:");
+  std::string end_html("\nEndHTML:");
+  std::string start_fragment("\nStartFragment:");
+  std::string end_fragment("\nEndFragment:");
+  std::string source_url("\nSourceURL:");
+
+  bool has_source_url = !src_url.empty() &&
+                        !StartsWithASCII(src_url, "about:", false);
+  if (has_source_url)
+    source_url.append(src_url);
+
+  std::string start_markup("\n<HTML>\n<BODY>\n<!--StartFragment-->\n");
+  std::string end_markup("\n<!--EndFragment-->\n</BODY>\n</HTML>");
+
+  // calculate offsets
+  const size_t kMaxDigits = 10; // number of digits in UINT_MAX in base 10
+
+  size_t start_html_offset, start_fragment_offset;
+  size_t end_fragment_offset, end_html_offset;
+
+  start_html_offset = html_fragment->length() +
+                      start_html.length() + end_html.length() +
+                      start_fragment.length() + end_fragment.length() +
+                      (has_source_url ? source_url.length() : 0) +
+                      (4*kMaxDigits);
+
+  start_fragment_offset = start_html_offset + start_markup.length();
+  end_fragment_offset = start_fragment_offset + markup_utf8.length();
+  end_html_offset = end_fragment_offset + end_markup.length();
+
+  // fill in needed data
+  start_html.append(StringPrintf("%010u", start_html_offset));
+  end_html.append(StringPrintf("%010u", end_html_offset));
+  start_fragment.append(StringPrintf("%010u", start_fragment_offset));
+  end_fragment.append(StringPrintf("%010u", end_fragment_offset));
+  start_markup.append(markup_utf8);
+
+  // create full html_fragment string from the fragments
+  html_fragment->append(start_html);
+  html_fragment->append(end_html);
+  html_fragment->append(start_fragment);
+  html_fragment->append(end_fragment);
+  if (has_source_url)
+    html_fragment->append(source_url);
+  html_fragment->append(start_markup);
+  html_fragment->append(end_markup);
+}
+
+// static
+void Clipboard::ParseHTMLClipboardFormat(const std::string& html_frag,
+                                         std::wstring* markup,
+                                         std::string* src_url) {
+  if (src_url) {
+    // Obtain SourceURL, if present
+    std::string src_url_str("SourceURL:");
+    size_t line_start = html_frag.find(src_url_str, 0);
+    if (line_start != std::string::npos) {
+      size_t src_start = line_start+src_url_str.length();
+      size_t src_end = html_frag.find("\n", line_start);
+
+      if (src_end != std::string::npos)
+        *src_url = html_frag.substr(src_start, src_end - src_start);
+    }
+  }
+
+  if (markup) {
+    // Find the markup between "<!--StartFragment -->" and
+    // "<!--EndFragment -->", accounting for browser quirks
+    size_t markup_start = html_frag.find('<', 0);
+    size_t tag_start = html_frag.find("StartFragment", markup_start);
+    size_t frag_start = html_frag.find('>', tag_start) + 1;
+    // Here we do something slightly differently than WebKit.  Webkit does a
+    // forward find for EndFragment, but that seems to be a bug if the html
+    // fragment actually includes the string "EndFragment"
+    size_t tag_end = html_frag.rfind("EndFragment", std::string::npos);
+    size_t frag_end = html_frag.rfind('<', tag_end);
+
+    TrimWhitespace(UTF8ToWide(html_frag.substr(frag_start,
+                                               frag_end - frag_start)),
+                   TRIM_ALL, markup);
+  }
+}
+
+// static
+void Clipboard::ParseBookmarkClipboardFormat(const std::wstring& bookmark,
+                                             std::wstring* title,
+                                             std::string* url) {
+  const wchar_t* const kDelim = L"\r\n";
+
+  const size_t title_end = bookmark.find_first_of(kDelim);
+  if (title)
+    title->assign(bookmark.substr(0, title_end));
+
+  if (url) {
+    const size_t url_start = bookmark.find_first_not_of(kDelim, title_end);
+    if (url_start != std::wstring::npos)
+      *url = WideToUTF8(bookmark.substr(url_start, std::wstring::npos));
+  }
+}