/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


#include "system.h"

#include "pipeimpl.h"

#include <osl/pipe.h>
#include <osl/diagnose.h>
#include <osl/thread.h>
#include <osl/mutex.h>
#include <osl/semaphor.h>
#include <osl/conditn.h>
#include <osl/interlck.h>
#include <osl/process.h>

#include <rtl/alloc.h>
#include <rtl/memory.h>

#define PIPESYSTEM    	"\\\\.\\pipe\\"
#define PIPEPREFIX    "OSL_PIPE_"

typedef struct
{
	sal_uInt32 m_Size;
	sal_uInt32 m_ReadPos;
	sal_uInt32 m_WritePos;
	BYTE   m_Data[1];
	
} oslPipeBuffer;

/*****************************************************************************/
/* oslPipeImpl */
/*****************************************************************************/

struct oslPipeImpl {
	oslInterlockedCount  m_Reference;
	HANDLE		 		 m_File;
	HANDLE				 m_NamedObject;
	PSECURITY_ATTRIBUTES m_Security;
	HANDLE				 m_ReadEvent;
	HANDLE				 m_WriteEvent;
	HANDLE				 m_AcceptEvent;
	rtl_uString*         m_Name;
	oslPipeError 		 m_Error;
	sal_Bool             m_bClosed;
};


/*****************************************************************************/
/* osl_create/destroy-PipeImpl */
/*****************************************************************************/

static oslInterlockedCount nPipes = 0;

oslPipe __osl_createPipeImpl(void)
{
	oslPipe pPipe;

	pPipe = (oslPipe) rtl_allocateZeroMemory(sizeof(struct oslPipeImpl));

	pPipe->m_bClosed = sal_False;
	pPipe->m_Reference = 0;
	pPipe->m_Name = NULL;
	pPipe->m_File = INVALID_HANDLE_VALUE;
	pPipe->m_NamedObject = INVALID_HANDLE_VALUE;

	pPipe->m_ReadEvent = CreateEvent(NULL, TRUE, FALSE, NULL); 
	pPipe->m_WriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL); 
	pPipe->m_AcceptEvent = CreateEvent(NULL, TRUE, FALSE, NULL); 

	return pPipe;
}

void __osl_destroyPipeImpl(oslPipe pPipe)
{
	if (pPipe != NULL)
	{
		if ( pPipe->m_NamedObject != INVALID_HANDLE_VALUE && pPipe->m_NamedObject != NULL )
			CloseHandle( pPipe->m_NamedObject );

		if (pPipe->m_Security != NULL)
		{
			rtl_freeMemory(pPipe->m_Security->lpSecurityDescriptor);
			rtl_freeMemory(pPipe->m_Security);
		}

		CloseHandle(pPipe->m_ReadEvent);
		CloseHandle(pPipe->m_WriteEvent);
		CloseHandle(pPipe->m_AcceptEvent);

		if (pPipe->m_Name)
			rtl_uString_release(pPipe->m_Name);

		rtl_freeMemory(pPipe);
	}
}


/*****************************************************************************/
/* osl_createPipe  */
/*****************************************************************************/
oslPipe SAL_CALL osl_createPipe(rtl_uString *strPipeName, oslPipeOptions Options, 
					   oslSecurity Security)
{
	rtl_uString* name = NULL;
	rtl_uString* path = NULL;
	rtl_uString* temp = NULL;
	oslPipe pPipe;

   	PSECURITY_ATTRIBUTES  pSecAttr = NULL;

	rtl_uString_newFromAscii(&path, PIPESYSTEM);
	rtl_uString_newFromAscii(&name, PIPEPREFIX);

	if ( /*IS_NT &&*/ Security)
	{
		rtl_uString *Ident = NULL;
		rtl_uString *Delim = NULL;

		OSL_VERIFY(osl_getUserIdent(Security, &Ident));
		rtl_uString_newFromAscii(&Delim, "_");

		rtl_uString_newConcat(&temp, name, Ident);
		rtl_uString_newConcat(&name, temp, Delim);

		rtl_uString_release(Ident);
		rtl_uString_release(Delim);
	}
	else
	{
		if (Options & osl_Pipe_CREATE)
		{
	    	PSECURITY_DESCRIPTOR pSecDesc;

	    	pSecDesc = (PSECURITY_DESCRIPTOR) rtl_allocateMemory(SECURITY_DESCRIPTOR_MIN_LENGTH);

	    	/* add a NULL disc. ACL to the security descriptor */
		    OSL_VERIFY(InitializeSecurityDescriptor(pSecDesc, SECURITY_DESCRIPTOR_REVISION));
	    	OSL_VERIFY(SetSecurityDescriptorDacl(pSecDesc, TRUE, (PACL) NULL, FALSE));

			pSecAttr = rtl_allocateMemory(sizeof(SECURITY_ATTRIBUTES));
	    	pSecAttr->nLength = sizeof(SECURITY_ATTRIBUTES);
	    	pSecAttr->lpSecurityDescriptor = pSecDesc;
	    	pSecAttr->bInheritHandle = TRUE;
		}
	}

	rtl_uString_assign(&temp, name);
	rtl_uString_newConcat(&name, temp, strPipeName);

	/* alloc memory */
	pPipe= __osl_createPipeImpl();
	osl_incrementInterlockedCount(&(pPipe->m_Reference));

	/* build system pipe name */
	rtl_uString_assign(&temp, path);
	rtl_uString_newConcat(&path, temp, name);
	rtl_uString_release(temp);
	temp = NULL;

	if (Options & osl_Pipe_CREATE)
	{
		SetLastError( ERROR_SUCCESS );

		if ( IS_NT )
			pPipe->m_NamedObject = CreateMutexW( NULL, FALSE, name->buffer );
		else
		{
			LPSTR	pszTempBuffer = NULL;
			int		nCharsNeeded;

			nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, name->buffer, name->length, NULL, 0, NULL, NULL );
			pszTempBuffer = alloca( nCharsNeeded * sizeof(CHAR) );
			nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, name->buffer, name->length, pszTempBuffer, nCharsNeeded, NULL, NULL );
			pszTempBuffer[nCharsNeeded-1] = 0;

			pPipe->m_NamedObject = CreateMutexA( NULL, FALSE, pszTempBuffer );
		}

		if ( pPipe->m_NamedObject != INVALID_HANDLE_VALUE && pPipe->m_NamedObject != NULL )
		{
			if ( GetLastError() != ERROR_ALREADY_EXISTS )
			{
				pPipe->m_Security = pSecAttr;
				rtl_uString_assign(&pPipe->m_Name, name);

				if (IS_NT)
				{
					/* try to open system pipe */
					pPipe->m_File = CreateNamedPipeW(
						path->buffer, 
						PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
						PIPE_WAIT | PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE,
						PIPE_UNLIMITED_INSTANCES,
						4096, 4096,
						NMPWAIT_WAIT_FOREVER, 
						pPipe->m_Security);

					if (pPipe->m_File != INVALID_HANDLE_VALUE)
					{
						rtl_uString_release( name );
						rtl_uString_release( path );

						return pPipe;
					}
				}
				else /* Win 9x */
				{
					LPSTR	pszTempBuffer = NULL;
					int		nCharsNeeded;

					nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, path->buffer, path->length, NULL, 0, NULL, NULL );
					pszTempBuffer = alloca( nCharsNeeded * sizeof(CHAR) );
					nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, path->buffer, path->length, pszTempBuffer, nCharsNeeded, NULL, NULL );
					pszTempBuffer[nCharsNeeded-1] = 0;

					pPipe->m_File = CreateSimplePipe( pszTempBuffer );

					if ( IsValidHandle(pPipe->m_File) )
					{
						rtl_uString_release( name );
						rtl_uString_release( path );

						return pPipe;
					}
				}
			}
			else
			{
				CloseHandle( pPipe->m_NamedObject );
				pPipe->m_NamedObject = INVALID_HANDLE_VALUE;
			}
		}
	}
	else
	{
		if (IS_NT)
		{
			BOOL	fPipeAvailable;

			do
			{
				/* free instance should be available first */
				fPipeAvailable = WaitNamedPipeW(path->buffer, NMPWAIT_WAIT_FOREVER);

				/* first try to open system pipe */
				if ( fPipeAvailable )
				{
					pPipe->m_File = CreateFileW(
							path->buffer,
							GENERIC_READ|GENERIC_WRITE, 
							FILE_SHARE_READ | FILE_SHARE_WRITE,
							NULL,
							OPEN_EXISTING, 
							FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, 
							NULL);

					if ( pPipe->m_File != INVALID_HANDLE_VALUE )
					{
						// We got it !
						rtl_uString_release( name );
						rtl_uString_release( path );

						return (pPipe);
					}
					else
					{
						// Pipe instance maybe catched by another client -> try again
					}
				}
			} while ( fPipeAvailable );
		}
		else /* Win 9x */
		{
			LPSTR	pszTempBuffer = NULL;
			int		nCharsNeeded;

			nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, path->buffer, path->length, NULL, 0, NULL, NULL );
			pszTempBuffer = alloca( nCharsNeeded * sizeof(CHAR) );
			nCharsNeeded = WideCharToMultiByte( CP_ACP, 0, path->buffer, path->length, pszTempBuffer, nCharsNeeded, NULL, NULL );
			pszTempBuffer[nCharsNeeded-1] = 0;

			pPipe->m_File = OpenSimplePipe( pszTempBuffer );

			if ( IsValidHandle(pPipe->m_File) )
			{
				// We got it !
				rtl_uString_release( name );
				rtl_uString_release( path );

				return (pPipe);
			}
		}
	}

	/* if we reach here something went wrong */
	__osl_destroyPipeImpl(pPipe);

	return NULL;
}

void SAL_CALL osl_acquirePipe( oslPipe pPipe )
{
	osl_incrementInterlockedCount( &(pPipe->m_Reference) );
}

void SAL_CALL osl_releasePipe( oslPipe pPipe )
{
//  	OSL_ASSERT( pPipe );
	
	if( 0 == pPipe )
		return;
	
	if( 0 == osl_decrementInterlockedCount( &(pPipe->m_Reference) ) )
	{
		if( ! pPipe->m_bClosed )
			osl_closePipe( pPipe );
		
		__osl_destroyPipeImpl( pPipe );
	}
}

void SAL_CALL osl_closePipe( oslPipe pPipe )
{
	if( pPipe && ! pPipe->m_bClosed )
	{
		pPipe->m_bClosed = sal_True;
		if (IS_NT)
		{
			/* if we have a system pipe close it */
			if (pPipe->m_File != INVALID_HANDLE_VALUE)
			{
				/*			FlushFileBuffers(pPipe->m_File); */
				DisconnectNamedPipe(pPipe->m_File);
				CloseHandle(pPipe->m_File);
			}
		}
		else
		{
			CloseSimplePipe( pPipe->m_File );
		}

	}
}

/*****************************************************************************/
/* osl_acceptPipe  */
/*****************************************************************************/
oslPipe SAL_CALL osl_acceptPipe(oslPipe pPipe)
{
	oslPipe  pAcceptedPipe = NULL;
	
	HANDLE		 Event;
    OVERLAPPED   os;

	OSL_ASSERT(pPipe);

	if (IS_NT)
	{
		DWORD nBytesTransfered;
		rtl_uString* path = NULL;
		rtl_uString* temp = NULL;

		OSL_ASSERT (pPipe->m_File != INVALID_HANDLE_VALUE);

		Event = pPipe->m_AcceptEvent;
		rtl_zeroMemory(&os, sizeof(OVERLAPPED));
		os.hEvent = pPipe->m_AcceptEvent;
		ResetEvent(pPipe->m_AcceptEvent);

		if ( !ConnectNamedPipe(pPipe->m_File, &os))
		{
			switch ( GetLastError() )
			{
			case ERROR_PIPE_CONNECTED:	// Client already connected to pipe
			case ERROR_NO_DATA:			// Client was connected but has already closed pipe end
										// should only appear in nonblocking mode but in fact does
										// in blocking asynchronous mode.
				break;
			case ERROR_PIPE_LISTENING:	// Only for nonblocking mode but see ERROR_NO_DATA
			case ERROR_IO_PENDING:		// This is normal if not client is connected yet
			case ERROR_MORE_DATA:		// Should not happen
				// blocking call to accept
				if( !GetOverlappedResult( pPipe->m_File, &os, &nBytesTransfered, TRUE ) )
				{
					// Possible error could be that between ConnectNamedPipe and GetOverlappedResult a connect
					// took place.

					switch ( GetLastError() )
					{
					case ERROR_PIPE_CONNECTED:	// Pipe was already connected
					case ERROR_NO_DATA:			// Pipe was connected but client has already closed -> ver fast client ;-)
						break;					// Everything's fine !!!
					default:
						// Something went wrong
						return 0;
					}
				}
				break;
			default:					// All other error say that somethings going wrong.
				return 0;
			}
		}

		
		pAcceptedPipe = __osl_createPipeImpl();
		OSL_ASSERT(pAcceptedPipe);

		osl_incrementInterlockedCount(&(pAcceptedPipe->m_Reference));
		rtl_uString_assign(&pAcceptedPipe->m_Name, pPipe->m_Name);
		pAcceptedPipe->m_File = pPipe->m_File;

		rtl_uString_newFromAscii(&temp, PIPESYSTEM);
		rtl_uString_newConcat(&path, temp, pPipe->m_Name);
		rtl_uString_release(temp);

		// prepare for next accept
		pPipe->m_File = 
        	CreateNamedPipeW(path->buffer, 
				PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED,
				PIPE_WAIT | PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE,
				PIPE_UNLIMITED_INSTANCES,
				4096, 4096,
				NMPWAIT_WAIT_FOREVER, 
				pAcceptedPipe->m_Security);
		rtl_uString_release( path );
	}
	else /* Win9x */
	{
		pAcceptedPipe = __osl_createPipeImpl();
		OSL_ASSERT(pAcceptedPipe);

		osl_incrementInterlockedCount(&(pAcceptedPipe->m_Reference));
		rtl_uString_assign(&pAcceptedPipe->m_Name, pPipe->m_Name);
		pAcceptedPipe->m_File = pPipe->m_File;

		pAcceptedPipe->m_File = AcceptSimplePipeConnection( pPipe->m_File );
	}

	return pAcceptedPipe;
}

/*****************************************************************************/
/* osl_receivePipe  */
/*****************************************************************************/
sal_Int32 SAL_CALL osl_receivePipe(oslPipe pPipe,
						void* pBuffer,
						sal_Int32 BytesToRead)
{
    DWORD nBytes;

	OSL_ASSERT(pPipe);

	/* if we have a system pipe use it */
	if ( IS_NT /*pPipe->m_File != INVALID_HANDLE_VALUE*/)
	{
		OVERLAPPED   os;
		rtl_zeroMemory(&os,sizeof(OVERLAPPED));
		os.hEvent = pPipe->m_ReadEvent;

		ResetEvent(pPipe->m_ReadEvent);
			
		if (! ReadFile(pPipe->m_File, pBuffer, BytesToRead, &nBytes, &os) &&
			((GetLastError() != ERROR_IO_PENDING) ||
			 ! GetOverlappedResult(pPipe->m_File, &os, &nBytes, TRUE)))
		{
			DWORD lastError = GetLastError();

			if (lastError == ERROR_MORE_DATA)
				nBytes = BytesToRead;
	  		else 
	  		{
	  			if (lastError == ERROR_PIPE_NOT_CONNECTED)
					nBytes = 0;
				else			
					nBytes = (DWORD) -1;

			 	pPipe->m_Error = osl_Pipe_E_ConnectionAbort;
			}
		}
	}			
	else
	{
		BOOL fSuccess = ReadSimplePipe( pPipe->m_File, pBuffer, BytesToRead, &nBytes, TRUE );

		if ( !fSuccess )
		{
			nBytes = 0;
		 	pPipe->m_Error = osl_Pipe_E_ConnectionAbort;
		}

	}

	return (nBytes);    
}

/*****************************************************************************/
/* osl_sendPipe  */
/*****************************************************************************/
sal_Int32 SAL_CALL osl_sendPipe(oslPipe pPipe,
					   const void* pBuffer,
					   sal_Int32 BytesToSend)
{
    DWORD nBytes;
	OSL_ASSERT(pPipe);

	if (IS_NT/*pPipe->m_File != INVALID_HANDLE_VALUE*/)
	{
		OVERLAPPED   os;
		rtl_zeroMemory(&os, sizeof(OVERLAPPED));
		os.hEvent = pPipe->m_WriteEvent;
		ResetEvent(pPipe->m_WriteEvent);

		if (! WriteFile(pPipe->m_File, pBuffer, BytesToSend, &nBytes, &os) &&
			((GetLastError() != ERROR_IO_PENDING) ||
			  ! GetOverlappedResult(pPipe->m_File, &os, &nBytes, TRUE)))
		{
		  	if (GetLastError() == ERROR_PIPE_NOT_CONNECTED)
				nBytes = 0;
			else			
				nBytes = (DWORD) -1;

		 	pPipe->m_Error = osl_Pipe_E_ConnectionAbort;
		}
	}			
	else
	{
		BOOL fSuccess = WriteSimplePipe( pPipe->m_File, pBuffer, BytesToSend, &nBytes, TRUE );

		if ( !fSuccess )
		{
			nBytes = 0;
		 	pPipe->m_Error = osl_Pipe_E_ConnectionAbort;
		}
	}
			
	return (nBytes);
}

sal_Int32 SAL_CALL osl_writePipe( oslPipe pPipe, const void *pBuffer , sal_Int32 n )
{
	/* loop until all desired bytes were send or an error occurred */
	sal_Int32 BytesSend= 0;
	sal_Int32 BytesToSend= n;

	OSL_ASSERT(pPipe);
	while (BytesToSend > 0) 
	{
		sal_Int32 RetVal;

		RetVal= osl_sendPipe(pPipe, pBuffer, BytesToSend);

		/* error occurred? */
		if(RetVal <= 0)
		{
			break;
		}

		BytesToSend -= RetVal;
		BytesSend += RetVal;
		pBuffer= (sal_Char*)pBuffer + RetVal;
	}

	return BytesSend;   
}

sal_Int32 SAL_CALL osl_readPipe( oslPipe pPipe, void *pBuffer , sal_Int32 n )
{
	/* loop until all desired bytes were read or an error occurred */
	sal_Int32 BytesRead= 0;
	sal_Int32 BytesToRead= n;

	OSL_ASSERT( pPipe );
	while (BytesToRead > 0) 
	{
		sal_Int32 RetVal;
		RetVal= osl_receivePipe(pPipe, pBuffer, BytesToRead);

		/* error occurred? */
		if(RetVal <= 0)
		{
			break;
		}

		BytesToRead -= RetVal;
		BytesRead += RetVal;
		pBuffer= (sal_Char*)pBuffer + RetVal;
	}
	return BytesRead;
}


/*****************************************************************************/
/* osl_getLastPipeError  */
/*****************************************************************************/
oslPipeError SAL_CALL osl_getLastPipeError(oslPipe pPipe)
{
	oslPipeError Error;

	if (pPipe != NULL)
	{
		Error = pPipe->m_Error;
		pPipe->m_Error = osl_Pipe_E_None;
	}
	else
		Error = osl_Pipe_E_NotFound;

	return (Error);
}