haiku-beta6/src/kits/app/Clipboard.cpp

//------------------------------------------------------------------------------
//	Copyright (c) 2001-2004, Haiku
//
//	Permission is hereby granted, free of charge, to any person obtaining a
//	copy of this software and associated documentation files (the "Software"),
//	to deal in the Software without restriction, including without limitation
//	the rights to use, copy, modify, merge, publish, distribute, sublicense,
//	and/or sell copies of the Software, and to permit persons to whom the
//	Software is furnished to do so, subject to the following conditions:
//
//	The above copyright notice and this permission notice shall be included in
//	all copies or substantial portions of the Software.
//
//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//	FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
//	DEALINGS IN THE SOFTWARE.
//
//	File Name:		Clipboard.cpp
//	Author:			Gabe Yoder ([email protected])
//	Description:	BClipboard provides an interface to a system-wide clipboard
//                  storage area.
//------------------------------------------------------------------------------

// Standard Includes -----------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// System Includes -------------------------------------------------------------
#include <Clipboard.h>
#include <Application.h>
#include <RegistrarDefs.h>
#include <RosterPrivate.h>

// Globals ---------------------------------------------------------------------
BClipboard *be_clipboard;
	// ToDo: this has to be initialized!


BClipboard::BClipboard(const char *name, bool transient)
{
	if (name != NULL)
		fName = strdup(name);
	else
		fName = strdup("system");

	fData = new BMessage();
	fCount = 0;
	fSystemCount = 0;

	BMessage message(B_REG_GET_CLIPBOARD_MESSENGER), reply;
	if (BRoster::Private().SendTo(&message, &reply, false) == B_OK
		&& reply.what == B_REG_SUCCESS
		&& reply.FindMessenger("messenger", &fClipHandler) == B_OK) {
		BMessage handlerMessage(B_REG_ADD_CLIPBOARD), handlerReply;
		int32 result;
		if (handlerMessage.AddString("name", fName) == B_OK
			&& fClipHandler.SendMessage(&handlerMessage, &handlerReply) == B_OK)
			handlerReply.FindInt32("result", &result);
	}
}


BClipboard::~BClipboard()
{
	free(fName);
	delete fData;
}


const char *
BClipboard::Name() const
{
	return (const char *)fName;
}


uint32
BClipboard::LocalCount() const
{
	/* fSystemCount contains the total number of writes to the clipboard.
	 * fCount contains the number of writes to the clipboard done by this
	 * BClipboard.
	 */
	return fSystemCount;
}


uint32
BClipboard::SystemCount() const
{
	int32 value;
	BMessage message(B_REG_GET_CLIPBOARD_COUNT), reply;
	if (message.AddString("name", fName) == B_OK
		&& fClipHandler.SendMessage(&message, &reply) == B_OK
		&& reply.FindInt32("count", &value) == B_OK)
		return (uint32)value;

	return 0;
}


status_t
BClipboard::StartWatching(BMessenger target)
{
	BMessage message(B_REG_CLIPBOARD_START_WATCHING), reply;
	if (message.AddString("name", fName) == B_OK
		&& message.AddMessenger("target", target) == B_OK
		&& fClipHandler.SendMessage(&message, &reply) == B_OK) {
		int32 result;
		reply.FindInt32("result", &result);
		return result;
	}
	return B_ERROR;
}


status_t
BClipboard::StopWatching(BMessenger target)
{
	BMessage message(B_REG_CLIPBOARD_STOP_WATCHING), reply;
	if (message.AddString("name", fName) == B_OK
		&& message.AddMessenger("target", target) == B_OK
		&& fClipHandler.SendMessage(&message, &reply) == B_OK) {
		int32 result;
		reply.FindInt32("result", &result);
		return result;
	}
	return B_ERROR;
}


bool
BClipboard::Lock()
{
	// Will this work correctly if clipboard is deleted while still waiting on
	// fLock.Lock() ?
	bool locked = fLock.Lock();
	if (locked && DownloadFromSystem() != B_OK) {
		locked = false;
		fLock.Unlock();
	}

	return locked;
}


void
BClipboard::Unlock()
{
	fLock.Unlock();
}


bool
BClipboard::IsLocked() const
{
	return fLock.IsLocked();
}


status_t
BClipboard::Clear()
{
	if (!AssertLocked())
		return B_NOT_ALLOWED;

	return fData->MakeEmpty();
}


status_t
BClipboard::Commit()
{
	if (!AssertLocked())
		return B_NOT_ALLOWED;

	return UploadToSystem();
}


status_t
BClipboard::Revert()
{
	if (!AssertLocked())
		return B_NOT_ALLOWED;
		
	status_t status = fData->MakeEmpty();
	if (status == B_OK)
		status = DownloadFromSystem();

	return status;
}


BMessenger
BClipboard::DataSource() const
{
	return fDataSource;
}


BMessage *
BClipboard::Data() const
{
	if (!AssertLocked())
		return NULL;

    return fData;
}


//	#pragma mark -
//	Private methods


BClipboard::BClipboard(const BClipboard &)
{
	// This is private, and I don't use it, so I'm not going to implement it
}


BClipboard & BClipboard::operator=(const BClipboard &)
{
	// This is private, and I don't use it, so I'm not going to implement it
	return *this;
}


void BClipboard::_ReservedClipboard1() {}
void BClipboard::_ReservedClipboard2() {}
void BClipboard::_ReservedClipboard3() {}


bool
BClipboard::AssertLocked() const
{
	// This function is for jumping to the debugger if not locked
	if (!fLock.IsLocked()) {
		debugger("The clipboard must be locked before proceeding.");
		return false;
	}
	return true;
}


status_t
BClipboard::DownloadFromSystem(bool force)
{
	// Apparently, the force paramater was used in some sort of
	// optimization in R5. Currently, we ignore it.
	BMessage message(B_REG_DOWNLOAD_CLIPBOARD), reply;
	if (message.AddString("name", fName) == B_OK
		&& fClipHandler.SendMessage(&message, &reply) == B_OK
		&& reply.FindMessage("data", fData) == B_OK
		&& reply.FindMessenger("data source", &fDataSource) == B_OK
		&& reply.FindInt32("count", (int32 *)&fSystemCount) == B_OK)
		return B_OK;

	return B_ERROR;
}


status_t
BClipboard::UploadToSystem()
{
	BMessage message(B_REG_UPLOAD_CLIPBOARD), reply;
	if (message.AddString("name", fName) == B_OK
		&& message.AddMessage("data", fData) == B_OK
		&& message.AddMessenger("data source", be_app_messenger) == B_OK
		&& fClipHandler.SendMessage(&message, &reply) == B_OK
		&& reply.FindInt32("count", (int32 *)&fSystemCount) == B_OK) {
		fCount++;
		return B_OK;
	}
	return B_ERROR;
}