base/clipboard_win.cc - chromium/src - Git at Google

 // 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.

 // Many of these functions are based on those found in
 // webkit/port/platform/PasteboardWin.cpp

 #include "base/clipboard.h"

 #include <shlobj.h>
 #include <shellapi.h>

 #include "base/clipboard_util.h"
 #include "base/file_path.h"
 #include "base/gfx/size.h"
 #include "base/lock.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/shared_memory.h"
 #include "base/string_util.h"

 namespace {

 // A scoper to manage acquiring and automatically releasing the clipboard.
 class ScopedClipboard {
  public:
   ScopedClipboard() : opened_(false) { }

   ~ScopedClipboard() {
     if (opened_)
       Release();
   }

   bool Acquire(HWND owner) {
     const int kMaxAttemptsToOpenClipboard = 5;

     if (opened_) {
       NOTREACHED();
       return false;
     }

     // Attempt to open the clipboard, which will acquire the Windows clipboard
     // lock.  This may fail if another process currently holds this 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 contention.

     for (int attempts = 0; attempts < kMaxAttemptsToOpenClipboard; ++attempts) {
       // If we didn't manage to open the clipboard, sleep a bit and be hopeful.
       if (attempts != 0)
         ::Sleep(5);

       if (::OpenClipboard(owner)) {
         opened_ = true;
         return true;
       }
     }

     // We failed to acquire the clipboard.
     return false;
   }

   void Release() {
     if (opened_) {
       ::CloseClipboard();
       opened_ = false;
     } else {
       NOTREACHED();
     }
   }

  private:
   bool opened_;
 };

 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() : create_window_(false) {
   if (MessageLoop::current()->type() == MessageLoop::TYPE_UI) {
     // 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);
     create_window_ = true;
   }

   clipboard_owner_ = NULL;
 }

 Clipboard::~Clipboard() {
   if (clipboard_owner_)
     ::DestroyWindow(clipboard_owner_);
   clipboard_owner_ = NULL;
 }

 void Clipboard::WriteObjects(const ObjectMap& objects) {
   WriteObjects(objects, NULL);
 }

 void Clipboard::WriteObjects(const ObjectMap& objects,
                              base::ProcessHandle process) {
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return;

   ::EmptyClipboard();

   for (ObjectMap::const_iterator iter = objects.begin();
        iter != objects.end(); ++iter) {
     if (iter->first == CBF_SMBITMAP)
       WriteBitmapFromSharedMemory(&(iter->second[0].front()),
                                   &(iter->second[1].front()),
                                   process);
     else
       DispatchObject(static_cast<ObjectType>(iter->first), iter->second);
   }
 }

 void Clipboard::WriteText(const char* text_data, size_t text_len) {
   string16 text;
   UTF8ToUTF16(text_data, text_len, &text);
   HGLOBAL glob = CreateGlobalData(text);

   WriteToClipboard(CF_UNICODETEXT, glob);
 }

 void Clipboard::WriteHTML(const char* markup_data,
                           size_t markup_len,
                           const char* url_data,
                           size_t url_len) {
   std::string markup(markup_data, markup_len);
   std::string url;

   if (url_len > 0)
     url.assign(url_data, url_len);

   std::string html_fragment = ClipboardUtil::HtmlToCFHtml(markup, url);
   HGLOBAL glob = CreateGlobalData(html_fragment);

   WriteToClipboard(StringToInt(GetHtmlFormatType()), glob);
 }

 void Clipboard::WriteBookmark(const char* title_data,
                               size_t title_len,
                               const char* url_data,
                               size_t url_len) {
   std::string bookmark(title_data, title_len);
   bookmark.append(1, L'\n');
   bookmark.append(url_data, url_len);

   string16 wide_bookmark = UTF8ToWide(bookmark);
   HGLOBAL glob = CreateGlobalData(wide_bookmark);

   WriteToClipboard(StringToInt(GetUrlWFormatType()), glob);
 }

 void Clipboard::WriteHyperlink(const char* title_data,
                                size_t title_len,
                                const char* url_data,
                                size_t url_len) {
   // Store as a bookmark.
   WriteBookmark(title_data, title_len, url_data, url_len);

   std::string title(title_data, title_len),
       url(url_data, url_len),
       link("<a href=\"");

   // Construct the hyperlink.
   link.append(url);
   link.append("\">");
   link.append(title);
   link.append("</a>");

   // Store hyperlink as html.
   WriteHTML(link.c_str(), link.size(), NULL, 0);
 }

 void Clipboard::WriteWebSmartPaste() {
   DCHECK(clipboard_owner_);
   ::SetClipboardData(StringToInt(GetWebKitSmartPasteFormatType()), NULL);
 }

 void Clipboard::WriteBitmap(const char* pixel_data, const char* size_data) {
   const gfx::Size* size = reinterpret_cast<const gfx::Size*>(size_data);
   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, pixel_data, 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 char* bitmap_data,
                                             const char* size_data,
                                             base::ProcessHandle process) {
   const gfx::Size* size = reinterpret_cast<const gfx::Size*>(size_data);

   // bitmap_data has an encoded shared memory object. See
   // DuplicateRemoteHandles().
   char* ptr = const_cast<char*>(bitmap_data);
   scoped_ptr<const base::SharedMemory> bitmap(*
       reinterpret_cast<const base::SharedMemory**>(ptr));

   // 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();
   // Sets the vertical orientation.
   bm_info.bmiHeader.biHeight = -size->height();
   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) {
   // 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};
   ::GdiAlphaBlend(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);

   WriteToClipboard(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::WriteFiles(const char* file_data, size_t file_len) {
   // Calculate the amount of space we'll need store the strings and
   // a DROPFILES struct.
   size_t bytes = sizeof(DROPFILES) + file_len;

   HANDLE hdata = ::GlobalAlloc(GMEM_MOVEABLE, bytes);
   if (!hdata)
     return;

   char* data = static_cast<char*>(::GlobalLock(hdata));
   DROPFILES* drop_files = reinterpret_cast<DROPFILES*>(data);
   drop_files->pFiles = sizeof(DROPFILES);
   drop_files->fWide = TRUE;

   memcpy(data + sizeof(DROPFILES), file_data, file_len);

   ::GlobalUnlock(hdata);
   WriteToClipboard(CF_HDROP, hdata);
 }

 void Clipboard::WriteToClipboard(unsigned int format, HANDLE handle) {
   DCHECK(clipboard_owner_);
   if (handle && !::SetClipboardData(format, handle)) {
     DCHECK(ERROR_CLIPBOARD_NOT_OPEN != GetLastError());
     FreeData(format, handle);
   }
 }

 bool Clipboard::IsFormatAvailable(const Clipboard::FormatType& format) const {
   return ::IsClipboardFormatAvailable(StringToInt(format)) != FALSE;
 }

 void Clipboard::ReadText(string16* result) const {
   if (!result) {
     NOTREACHED();
     return;
   }

   result->clear();

   // Acquire the clipboard.
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return;

   HANDLE data = ::GetClipboardData(CF_UNICODETEXT);
   if (!data)
     return;

   result->assign(static_cast<const char16*>(::GlobalLock(data)));
   ::GlobalUnlock(data);
 }

 void Clipboard::ReadAsciiText(std::string* result) const {
   if (!result) {
     NOTREACHED();
     return;
   }

   result->clear();

   // Acquire the clipboard.
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return;

   HANDLE data = ::GetClipboardData(CF_TEXT);
   if (!data)
     return;

   result->assign(static_cast<const char*>(::GlobalLock(data)));
   ::GlobalUnlock(data);
 }

 void Clipboard::ReadHTML(string16* markup, std::string* src_url) const {
   if (markup)
     markup->clear();

   if (src_url)
     src_url->clear();

   // Acquire the clipboard.
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return;

   HANDLE data = ::GetClipboardData(StringToInt(GetHtmlFormatType()));
   if (!data)
     return;

   std::string html_fragment(static_cast<const char*>(::GlobalLock(data)));
   ::GlobalUnlock(data);

   std::string markup_utf8;
   ClipboardUtil::CFHtmlToHtml(html_fragment, &markup_utf8, src_url);
   markup->assign(UTF8ToWide(markup_utf8));
 }

 void Clipboard::ReadBookmark(string16* title, std::string* url) const {
   if (title)
     title->clear();

   if (url)
     url->clear();

   // Acquire the clipboard.
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return;

   HANDLE data = ::GetClipboardData(StringToInt(GetUrlWFormatType()));
   if (!data)
     return;

   string16 bookmark(static_cast<const char16*>(::GlobalLock(data)));
   ::GlobalUnlock(data);

   ParseBookmarkClipboardFormat(bookmark, title, url);
 }

 // Read a file in HDROP format from the clipboard.
 void Clipboard::ReadFile(FilePath* file) const {
   if (!file) {
     NOTREACHED();
     return;
   }

   *file = FilePath();
   std::vector<FilePath> files;
   ReadFiles(&files);

   // Take the first file, if available.
   if (!files.empty())
     *file = files[0];
 }

 // Read a set of files in HDROP format from the clipboard.
 void Clipboard::ReadFiles(std::vector<FilePath>* files) const {
   if (!files) {
     NOTREACHED();
     return;
   }

   files->clear();

   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     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(FilePath(file));
     }
   }
 }

 // static
 void Clipboard::ParseBookmarkClipboardFormat(const string16& bookmark,
                                              string16* title,
                                              std::string* url) {
   const string16 kDelim = ASCIIToUTF16("\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 != string16::npos)
       *url = UTF16ToUTF8(bookmark.substr(url_start, string16::npos));
   }
 }

 // static
 Clipboard::FormatType Clipboard::GetUrlFormatType() {
   return IntToString(ClipboardUtil::GetUrlFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetUrlWFormatType() {
   return IntToString(ClipboardUtil::GetUrlWFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetMozUrlFormatType() {
   return IntToString(ClipboardUtil::GetMozUrlFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetPlainTextFormatType() {
   return IntToString(ClipboardUtil::GetPlainTextFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetPlainTextWFormatType() {
   return IntToString(ClipboardUtil::GetPlainTextWFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetFilenameFormatType() {
   return IntToString(ClipboardUtil::GetFilenameFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetFilenameWFormatType() {
   return IntToString(ClipboardUtil::GetFilenameWFormat()->cfFormat);
 }

 // MS HTML Format
 // static
 Clipboard::FormatType Clipboard::GetHtmlFormatType() {
   return IntToString(ClipboardUtil::GetHtmlFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetBitmapFormatType() {
   return IntToString(CF_BITMAP);
 }

 // Firefox text/html
 // static
 Clipboard::FormatType Clipboard::GetTextHtmlFormatType() {
   return IntToString(ClipboardUtil::GetTextHtmlFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetCFHDropFormatType() {
   return IntToString(ClipboardUtil::GetCFHDropFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetFileDescriptorFormatType() {
   return IntToString(ClipboardUtil::GetFileDescriptorFormat()->cfFormat);
 }

 // static
 Clipboard::FormatType Clipboard::GetFileContentFormatZeroType() {
   return IntToString(ClipboardUtil::GetFileContentFormatZero()->cfFormat);
 }

 // static
 void Clipboard::DuplicateRemoteHandles(base::ProcessHandle process,
                                        ObjectMap* objects) {
   for (ObjectMap::iterator iter = objects->begin(); iter != objects->end();
        ++iter) {
     if (iter->first == CBF_SMBITMAP) {
       // There is a shared memory handle encoded on the first ObjectMapParam.
       // Use it to open a local handle to the memory.
       char* bitmap_data = &(iter->second[0].front());
       base::SharedMemoryHandle* remote_bitmap_handle =
           reinterpret_cast<base::SharedMemoryHandle*>(bitmap_data);

       base::SharedMemory* bitmap = new base::SharedMemory(*remote_bitmap_handle,
                                                           false, process);

       // We store the object where the remote handle was located so it can
       // be retrieved by the UI thread (see WriteBitmapFromSharedMemory()).
       iter->second[0].clear();
       for (size_t i = 0; i < sizeof(bitmap); i++)
         iter->second[0].push_back(reinterpret_cast<char*>(&bitmap)[i]);
     }
   }
 }

 // static
 Clipboard::FormatType Clipboard::GetWebKitSmartPasteFormatType() {
   return IntToString(ClipboardUtil::GetWebKitSmartPasteFormat()->cfFormat);
 }

 // static
 void Clipboard::FreeData(unsigned int format, HANDLE data) {
   if (format == CF_BITMAP)
     ::DeleteObject(static_cast<HBITMAP>(data));
   else
     ::GlobalFree(data);
 }

 HWND Clipboard::GetClipboardWindow() const {
   if (!clipboard_owner_ && create_window_) {
     clipboard_owner_ = ::CreateWindow(L"ClipboardOwnerWindowClass",
                                       L"ClipboardOwnerWindow",
                                       0, 0, 0, 0, 0,
                                       HWND_MESSAGE,
                                       0, 0, 0);
   }
   return clipboard_owner_;
 }
	// 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.

	// Many of these functions are based on those found in
	// webkit/port/platform/PasteboardWin.cpp

	#include "base/clipboard.h"

	#include <shlobj.h>
	#include <shellapi.h>

	#include "base/clipboard_util.h"
	#include "base/file_path.h"
	#include "base/gfx/size.h"
	#include "base/lock.h"
	#include "base/logging.h"
	#include "base/message_loop.h"
	#include "base/shared_memory.h"
	#include "base/string_util.h"

	namespace {

	// A scoper to manage acquiring and automatically releasing the clipboard.
	class ScopedClipboard {
	public:
	ScopedClipboard() : opened_(false) { }

	~ScopedClipboard() {
	if (opened_)
	Release();
	}

	bool Acquire(HWND owner) {
	const int kMaxAttemptsToOpenClipboard = 5;

	if (opened_) {
	NOTREACHED();
	return false;
	}

	// Attempt to open the clipboard, which will acquire the Windows clipboard
	// lock. This may fail if another process currently holds this 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 contention.

	for (int attempts = 0; attempts < kMaxAttemptsToOpenClipboard; ++attempts) {
	// If we didn't manage to open the clipboard, sleep a bit and be hopeful.
	if (attempts != 0)
	::Sleep(5);

	if (::OpenClipboard(owner)) {
	opened_ = true;
	return true;
	}
	}

	// We failed to acquire the clipboard.
	return false;
	}

	void Release() {
	if (opened_) {
	::CloseClipboard();
	opened_ = false;
	} else {
	NOTREACHED();
	}
	}

	private:
	bool opened_;
	};

	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() : create_window_(false) {
	if (MessageLoop::current()->type() == MessageLoop::TYPE_UI) {
	// 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);
	create_window_ = true;
	}

	clipboard_owner_ = NULL;
	}

	Clipboard::~Clipboard() {
	if (clipboard_owner_)
	::DestroyWindow(clipboard_owner_);
	clipboard_owner_ = NULL;
	}

	void Clipboard::WriteObjects(const ObjectMap& objects) {
	WriteObjects(objects, NULL);
	}

	void Clipboard::WriteObjects(const ObjectMap& objects,
	base::ProcessHandle process) {
	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	return;

	::EmptyClipboard();

	for (ObjectMap::const_iterator iter = objects.begin();
	iter != objects.end(); ++iter) {
	if (iter->first == CBF_SMBITMAP)
	WriteBitmapFromSharedMemory(&(iter->second[0].front()),
	&(iter->second[1].front()),
	process);
	else
	DispatchObject(static_cast<ObjectType>(iter->first), iter->second);
	}
	}

	void Clipboard::WriteText(const char* text_data, size_t text_len) {
	string16 text;
	UTF8ToUTF16(text_data, text_len, &text);
	HGLOBAL glob = CreateGlobalData(text);

	WriteToClipboard(CF_UNICODETEXT, glob);
	}

	void Clipboard::WriteHTML(const char* markup_data,
	size_t markup_len,
	const char* url_data,
	size_t url_len) {
	std::string markup(markup_data, markup_len);
	std::string url;

	if (url_len > 0)
	url.assign(url_data, url_len);

	std::string html_fragment = ClipboardUtil::HtmlToCFHtml(markup, url);
	HGLOBAL glob = CreateGlobalData(html_fragment);

	WriteToClipboard(StringToInt(GetHtmlFormatType()), glob);
	}

	void Clipboard::WriteBookmark(const char* title_data,
	size_t title_len,
	const char* url_data,
	size_t url_len) {
	std::string bookmark(title_data, title_len);
	bookmark.append(1, L'\n');
	bookmark.append(url_data, url_len);

	string16 wide_bookmark = UTF8ToWide(bookmark);
	HGLOBAL glob = CreateGlobalData(wide_bookmark);

	WriteToClipboard(StringToInt(GetUrlWFormatType()), glob);
	}

	void Clipboard::WriteHyperlink(const char* title_data,
	size_t title_len,
	const char* url_data,
	size_t url_len) {
	// Store as a bookmark.
	WriteBookmark(title_data, title_len, url_data, url_len);

	std::string title(title_data, title_len),
	url(url_data, url_len),
	link("<a href=\"");

	// Construct the hyperlink.
	link.append(url);
	link.append("\">");
	link.append(title);
	link.append("</a>");

	// Store hyperlink as html.
	WriteHTML(link.c_str(), link.size(), NULL, 0);
	}

	void Clipboard::WriteWebSmartPaste() {
	DCHECK(clipboard_owner_);
	::SetClipboardData(StringToInt(GetWebKitSmartPasteFormatType()), NULL);
	}

	void Clipboard::WriteBitmap(const char* pixel_data, const char* size_data) {
	const gfx::Size* size = reinterpret_cast<const gfx::Size*>(size_data);
	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, pixel_data, 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 char* bitmap_data,
	const char* size_data,
	base::ProcessHandle process) {
	const gfx::Size* size = reinterpret_cast<const gfx::Size*>(size_data);

	// bitmap_data has an encoded shared memory object. See
	// DuplicateRemoteHandles().
	char* ptr = const_cast<char*>(bitmap_data);
	scoped_ptr<const base::SharedMemory> bitmap(*
	reinterpret_cast<const base::SharedMemory**>(ptr));

	// 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();
	// Sets the vertical orientation.
	bm_info.bmiHeader.biHeight = -size->height();
	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) {
	// 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};
	::GdiAlphaBlend(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);

	WriteToClipboard(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::WriteFiles(const char* file_data, size_t file_len) {
	// Calculate the amount of space we'll need store the strings and
	// a DROPFILES struct.
	size_t bytes = sizeof(DROPFILES) + file_len;

	HANDLE hdata = ::GlobalAlloc(GMEM_MOVEABLE, bytes);
	if (!hdata)
	return;

	char* data = static_cast<char*>(::GlobalLock(hdata));
	DROPFILES* drop_files = reinterpret_cast<DROPFILES*>(data);
	drop_files->pFiles = sizeof(DROPFILES);
	drop_files->fWide = TRUE;

	memcpy(data + sizeof(DROPFILES), file_data, file_len);

	::GlobalUnlock(hdata);
	WriteToClipboard(CF_HDROP, hdata);
	}

	void Clipboard::WriteToClipboard(unsigned int format, HANDLE handle) {
	DCHECK(clipboard_owner_);
	if (handle && !::SetClipboardData(format, handle)) {
	DCHECK(ERROR_CLIPBOARD_NOT_OPEN != GetLastError());
	FreeData(format, handle);
	}
	}

	bool Clipboard::IsFormatAvailable(const Clipboard::FormatType& format) const {
	return ::IsClipboardFormatAvailable(StringToInt(format)) != FALSE;
	}

	void Clipboard::ReadText(string16* result) const {
	if (!result) {
	NOTREACHED();
	return;
	}

	result->clear();

	// Acquire the clipboard.
	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	return;

	HANDLE data = ::GetClipboardData(CF_UNICODETEXT);
	if (!data)
	return;

	result->assign(static_cast<const char16*>(::GlobalLock(data)));
	::GlobalUnlock(data);
	}

	void Clipboard::ReadAsciiText(std::string* result) const {
	if (!result) {
	NOTREACHED();
	return;
	}

	result->clear();

	// Acquire the clipboard.
	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	return;

	HANDLE data = ::GetClipboardData(CF_TEXT);
	if (!data)
	return;

	result->assign(static_cast<const char*>(::GlobalLock(data)));
	::GlobalUnlock(data);
	}

	void Clipboard::ReadHTML(string16* markup, std::string* src_url) const {
	if (markup)
	markup->clear();

	if (src_url)
	src_url->clear();

	// Acquire the clipboard.
	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	return;

	HANDLE data = ::GetClipboardData(StringToInt(GetHtmlFormatType()));
	if (!data)
	return;

	std::string html_fragment(static_cast<const char*>(::GlobalLock(data)));
	::GlobalUnlock(data);

	std::string markup_utf8;
	ClipboardUtil::CFHtmlToHtml(html_fragment, &markup_utf8, src_url);
	markup->assign(UTF8ToWide(markup_utf8));
	}

	void Clipboard::ReadBookmark(string16* title, std::string* url) const {
	if (title)
	title->clear();

	if (url)
	url->clear();

	// Acquire the clipboard.
	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	return;

	HANDLE data = ::GetClipboardData(StringToInt(GetUrlWFormatType()));
	if (!data)
	return;

	string16 bookmark(static_cast<const char16*>(::GlobalLock(data)));
	::GlobalUnlock(data);

	ParseBookmarkClipboardFormat(bookmark, title, url);
	}

	// Read a file in HDROP format from the clipboard.
	void Clipboard::ReadFile(FilePath* file) const {
	if (!file) {
	NOTREACHED();
	return;
	}

	*file = FilePath();
	std::vector<FilePath> files;
	ReadFiles(&files);

	// Take the first file, if available.
	if (!files.empty())
	*file = files[0];
	}

	// Read a set of files in HDROP format from the clipboard.
	void Clipboard::ReadFiles(std::vector<FilePath>* files) const {
	if (!files) {
	NOTREACHED();
	return;
	}

	files->clear();

	ScopedClipboard clipboard;
	if (!clipboard.Acquire(GetClipboardWindow()))
	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(FilePath(file));
	}
	}
	}

	// static
	void Clipboard::ParseBookmarkClipboardFormat(const string16& bookmark,
	string16* title,
	std::string* url) {
	const string16 kDelim = ASCIIToUTF16("\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 != string16::npos)
	*url = UTF16ToUTF8(bookmark.substr(url_start, string16::npos));
	}
	}

	// static
	Clipboard::FormatType Clipboard::GetUrlFormatType() {
	return IntToString(ClipboardUtil::GetUrlFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetUrlWFormatType() {
	return IntToString(ClipboardUtil::GetUrlWFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetMozUrlFormatType() {
	return IntToString(ClipboardUtil::GetMozUrlFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetPlainTextFormatType() {
	return IntToString(ClipboardUtil::GetPlainTextFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetPlainTextWFormatType() {
	return IntToString(ClipboardUtil::GetPlainTextWFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetFilenameFormatType() {
	return IntToString(ClipboardUtil::GetFilenameFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetFilenameWFormatType() {
	return IntToString(ClipboardUtil::GetFilenameWFormat()->cfFormat);
	}

	// MS HTML Format
	// static
	Clipboard::FormatType Clipboard::GetHtmlFormatType() {
	return IntToString(ClipboardUtil::GetHtmlFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetBitmapFormatType() {
	return IntToString(CF_BITMAP);
	}

	// Firefox text/html
	// static
	Clipboard::FormatType Clipboard::GetTextHtmlFormatType() {
	return IntToString(ClipboardUtil::GetTextHtmlFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetCFHDropFormatType() {
	return IntToString(ClipboardUtil::GetCFHDropFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetFileDescriptorFormatType() {
	return IntToString(ClipboardUtil::GetFileDescriptorFormat()->cfFormat);
	}

	// static
	Clipboard::FormatType Clipboard::GetFileContentFormatZeroType() {
	return IntToString(ClipboardUtil::GetFileContentFormatZero()->cfFormat);
	}

	// static
	void Clipboard::DuplicateRemoteHandles(base::ProcessHandle process,
	ObjectMap* objects) {
	for (ObjectMap::iterator iter = objects->begin(); iter != objects->end();
	++iter) {
	if (iter->first == CBF_SMBITMAP) {
	// There is a shared memory handle encoded on the first ObjectMapParam.
	// Use it to open a local handle to the memory.
	char* bitmap_data = &(iter->second[0].front());
	base::SharedMemoryHandle* remote_bitmap_handle =
	reinterpret_cast<base::SharedMemoryHandle*>(bitmap_data);

	base::SharedMemory* bitmap = new base::SharedMemory(*remote_bitmap_handle,
	false, process);

	// We store the object where the remote handle was located so it can
	// be retrieved by the UI thread (see WriteBitmapFromSharedMemory()).
	iter->second[0].clear();
	for (size_t i = 0; i < sizeof(bitmap); i++)
	iter->second[0].push_back(reinterpret_cast<char*>(&bitmap)[i]);
	}
	}
	}

	// static
	Clipboard::FormatType Clipboard::GetWebKitSmartPasteFormatType() {
	return IntToString(ClipboardUtil::GetWebKitSmartPasteFormat()->cfFormat);
	}

	// static
	void Clipboard::FreeData(unsigned int format, HANDLE data) {
	if (format == CF_BITMAP)
	::DeleteObject(static_cast<HBITMAP>(data));
	else
	::GlobalFree(data);
	}

	HWND Clipboard::GetClipboardWindow() const {
	if (!clipboard_owner_ && create_window_) {
	clipboard_owner_ = ::CreateWindow(L"ClipboardOwnerWindowClass",
	L"ClipboardOwnerWindow",
	0, 0, 0, 0, 0,
	HWND_MESSAGE,
	0, 0, 0);
	}
	return clipboard_owner_;
	}