Sweden-Number/scheduler/critsection.c

199 lines
5.3 KiB
C

/*
* Win32 critical sections
*
* Copyright 1998 Alexandre Julliard
*/
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/sem.h>
#include "debug.h"
#include "winerror.h"
#include "winbase.h"
#include "heap.h"
#include "k32obj.h"
#include "debug.h"
#include "thread.h"
/* On some systems this is supposed to be defined in the program */
#ifndef HAVE_UNION_SEMUN
union semun {
int val;
struct semid_ds *buf;
ushort *array;
};
#endif
/***********************************************************************
* InitializeCriticalSection (KERNEL32.472) (NTDLL.406)
*/
void WINAPI InitializeCriticalSection( CRITICAL_SECTION *crit )
{
crit->LockCount = -1;
crit->RecursionCount = 0;
crit->OwningThread = 0;
crit->LockSemaphore = 0;
if (SystemHeap)
{
crit->LockSemaphore = CreateSemaphoreA( NULL, 0, 1, NULL );
crit->Reserved = (DWORD)-1;
}
else
{
union semun val;
crit->Reserved = (DWORD)semget( IPC_PRIVATE, 1, IPC_CREAT | 0777 );
if (crit->Reserved == (DWORD)-1)
{
perror( "semget" );
return;
}
val.val = 0;
semctl( (int)crit->Reserved, 0, SETVAL, val );
}
}
/***********************************************************************
* DeleteCriticalSection (KERNEL32.185) (NTDLL.327)
*/
void WINAPI DeleteCriticalSection( CRITICAL_SECTION *crit )
{
if (crit->LockSemaphore)
{
if (crit->RecursionCount) /* Should not happen */
MSG("Deleting owned critical section (%p)\n", crit );
crit->LockCount = -1;
crit->RecursionCount = 0;
crit->OwningThread = 0;
CloseHandle( crit->LockSemaphore );
crit->LockSemaphore = 0;
}
else if (crit->Reserved != (DWORD)-1)
{
semctl( (int)crit->Reserved, 0, IPC_RMID, (union semun)0 );
}
}
/***********************************************************************
* EnterCriticalSection (KERNEL32.195) (NTDLL.344)
*/
void WINAPI EnterCriticalSection( CRITICAL_SECTION *crit )
{
if ( (crit->Reserved==-1) && !(crit->LockSemaphore) &&
(crit!=HEAP_SystemLock)
) {
FIXME(win32,"entering uninitialized section(%p)?\n",crit);
InitializeCriticalSection(crit);
}
if (InterlockedIncrement( &crit->LockCount ))
{
if (crit->OwningThread == GetCurrentThreadId())
{
crit->RecursionCount++;
return;
}
/* Now wait for it */
if (crit->LockSemaphore)
{
/* FIXME: should set a timeout and raise an exception */
WaitForSingleObject( crit->LockSemaphore, INFINITE );
}
else if (crit->Reserved != (DWORD)-1)
{
int ret;
struct sembuf sop;
sop.sem_num = 0;
sop.sem_op = -1;
sop.sem_flg = 0/*SEM_UNDO*/;
do
{
ret = semop( (int)crit->Reserved, &sop, 1 );
} while ((ret == -1) && (errno == EINTR));
}
else
{
MSG( "Uninitialized critical section (%p)\n", crit );
return;
}
}
crit->OwningThread = GetCurrentThreadId();
crit->RecursionCount = 1;
}
/***********************************************************************
* TryEnterCriticalSection (KERNEL32.898) (NTDLL.969)
*/
BOOL WINAPI TryEnterCriticalSection( CRITICAL_SECTION *crit )
{
if (InterlockedIncrement( &crit->LockCount ))
{
if (crit->OwningThread == GetCurrentThreadId())
{
crit->RecursionCount++;
return TRUE;
}
/* FIXME: this doesn't work */
InterlockedDecrement( &crit->LockCount );
return FALSE;
}
crit->OwningThread = GetCurrentThreadId();
crit->RecursionCount = 1;
return TRUE;
}
/***********************************************************************
* LeaveCriticalSection (KERNEL32.494) (NTDLL.426)
*/
void WINAPI LeaveCriticalSection( CRITICAL_SECTION *crit )
{
if (crit->OwningThread != GetCurrentThreadId()) return;
if (--crit->RecursionCount)
{
InterlockedDecrement( &crit->LockCount );
return;
}
crit->OwningThread = 0;
if (InterlockedDecrement( &crit->LockCount ) >= 0)
{
/* Someone is waiting */
if (crit->LockSemaphore)
{
ReleaseSemaphore( crit->LockSemaphore, 1, NULL );
}
else if (crit->Reserved != (DWORD)-1)
{
struct sembuf sop;
sop.sem_num = 0;
sop.sem_op = 1;
sop.sem_flg = 0/*SEM_UNDO*/;
semop( (int)crit->Reserved, &sop, 1 );
}
}
}
/***********************************************************************
* MakeCriticalSectionGlobal (KERNEL32.515)
*/
void WINAPI MakeCriticalSectionGlobal( CRITICAL_SECTION *crit )
{
crit->LockSemaphore = ConvertToGlobalHandle( crit->LockSemaphore );
}
/***********************************************************************
* ReinitializeCriticalSection (KERNEL32.581)
*/
void WINAPI ReinitializeCriticalSection( CRITICAL_SECTION *crit )
{
DeleteCriticalSection( crit );
InitializeCriticalSection( crit );
}