windows-nt/Source/XPSP1/NT/multimedia/media/dplayx/dplay/wsock/helpcli.c
2020-09-26 16:20:57 +08:00

217 lines
5.4 KiB
C

/*==========================================================================
*
* Copyright (C) 1994-1997 Microsoft Corporation. All Rights Reserved.
*
* File: helpcli.c
* Content: client code to talk to dplaysvr.exe
* allows multiple dplay winscock clients to share
* a single port. see %manroot%\dplay\dplaysvr\dphelp.c
* History:
* Date By Reason
* ==== == ======
* 2/15/97 andyco created from w95help.h
*
***************************************************************************/
#include "helpcli.h"
extern DWORD dwHelperPid;
/*
* sendRequest
*
* communicate a request to DPHELP
*/
static BOOL sendRequest( LPDPHELPDATA req_phd )
{
LPDPHELPDATA phd;
HANDLE hmem;
HANDLE hmutex;
HANDLE hackevent;
HANDLE hstartevent;
BOOL rc;
/*
* get events start/ack events
*/
hstartevent = CreateEvent( NULL, FALSE, FALSE, DPHELP_EVENT_NAME );
if( hstartevent == NULL )
{
return FALSE;
}
hackevent = CreateEvent( NULL, FALSE, FALSE, DPHELP_ACK_EVENT_NAME );
if( hackevent == NULL )
{
CloseHandle( hstartevent );
return FALSE;
}
/*
* create shared memory area
*/
hmem = CreateFileMapping( INVALID_HANDLE_VALUE, NULL,
PAGE_READWRITE, 0, sizeof( DPHELPDATA ),
DPHELP_SHARED_NAME );
if( hmem == NULL )
{
DPF( 1, "Could not create file mapping!" );
CloseHandle( hstartevent );
CloseHandle( hackevent );
return FALSE;
}
phd = (LPDPHELPDATA) MapViewOfFile( hmem, FILE_MAP_ALL_ACCESS, 0, 0, 0 );
if( phd == NULL )
{
DPF( 1, "Could not create view of file!" );
CloseHandle( hmem );
CloseHandle( hstartevent );
CloseHandle( hackevent );
return FALSE;
}
/*
* wait for access to the shared memory
*/
hmutex = OpenMutex( SYNCHRONIZE, FALSE, DPHELP_MUTEX_NAME );
if( hmutex == NULL )
{
DPF( 1, "Could not create mutex!" );
UnmapViewOfFile( phd );
CloseHandle( hmem );
CloseHandle( hstartevent );
CloseHandle( hackevent );
return FALSE;
}
WaitForSingleObject( hmutex, INFINITE );
/*
* wake up DPHELP with our request
*/
memcpy( phd, req_phd, sizeof( DPHELPDATA ) );
if( SetEvent( hstartevent ) )
{
WaitForSingleObject( hackevent, INFINITE );
memcpy( req_phd, phd, sizeof( DPHELPDATA ) );
rc = TRUE;
}
else
{
DPF( 1, "Could not signal event to notify DPHELP" );
rc = FALSE;
}
/*
* done with things
*/
ReleaseMutex( hmutex );
CloseHandle( hmutex );
CloseHandle( hstartevent );
CloseHandle( hackevent );
UnmapViewOfFile( phd );
CloseHandle( hmem );
return rc;
} /* sendRequest */
/*
* WaitForHelperStartup
*/
BOOL WaitForHelperStartup( void )
{
HANDLE hevent;
DWORD rc;
hevent = CreateEvent( NULL, TRUE, FALSE, DPHELP_STARTUP_EVENT_NAME );
if( hevent == NULL )
{
return FALSE;
}
DPF( 3, "Wait DPHELP startup event to be triggered" );
rc = WaitForSingleObject( hevent, INFINITE );
CloseHandle( hevent );
return TRUE;
} /* WaitForHelperStartup */
/*
* CreateHelperProcess
*/
BOOL CreateHelperProcess( LPDWORD ppid )
{
if( dwHelperPid == 0 )
{
STARTUPINFO si;
PROCESS_INFORMATION pi;
HANDLE h;
h = OpenEvent( SYNCHRONIZE, FALSE, DPHELP_STARTUP_EVENT_NAME );
if( h == NULL )
{
si.cb = sizeof(STARTUPINFO);
si.lpReserved = NULL;
si.lpDesktop = NULL;
si.lpTitle = NULL;
si.dwFlags = 0;
si.cbReserved2 = 0;
si.lpReserved2 = NULL;
DPF( 3, "Creating helper process dplaysvr.exe now" );
if( !CreateProcess(NULL, "dplaysvr.exe", NULL, NULL, FALSE,
NORMAL_PRIORITY_CLASS,
NULL, NULL, &si, &pi) )
{
DPF( 2, "Could not create DPHELP.EXE" );
return FALSE;
}
dwHelperPid = pi.dwProcessId;
DPF( 3, "Helper Process created" );
}
else
{
DPHELPDATA hd;
DPF( 3, "dplaysvr already exists, waiting for dplaysvr event" );
WaitForSingleObject( h, INFINITE );
CloseHandle( h );
DPF( 3, "Asking for DPHELP pid" );
hd.req = DPHELPREQ_RETURNHELPERPID;
sendRequest( &hd );
dwHelperPid = hd.pid;
DPF( 3, "DPHELP pid = %08lx", dwHelperPid );
}
*ppid = dwHelperPid;
return TRUE;
}
*ppid = dwHelperPid;
return FALSE;
} /* CreateHelperProcess */
// notify dphelp.c that we have a new server on this system
HRESULT HelperAddDPlayServer(USHORT port)
{
DPHELPDATA hd;
DWORD pid = GetCurrentProcessId();
memset(&hd, 0, sizeof(DPHELPDATA));
hd.req = DPHELPREQ_DPLAYADDSERVER;
hd.pid = pid;
hd.port = port;
if (sendRequest(&hd)) return hd.hr;
else return E_FAIL;
} // HelperAddDPlayServer
// server is going away
BOOL HelperDeleteDPlayServer(USHORT port)
{
DPHELPDATA hd;
DWORD pid = GetCurrentProcessId();
memset(&hd, 0, sizeof(DPHELPDATA));
hd.req = DPHELPREQ_DPLAYDELETESERVER;
hd.pid = pid;
hd.port = port;
return sendRequest(&hd);
} // HelperDeleteDPlayServer