scheduler/critsection.c

   1 /*
   2  * Win32 critical sections
   3  *
   4  * Copyright 1998 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <sys/types.h>
  11 #include "debug.h"
  12 #include "winerror.h"
  13 #include "winbase.h"
  14 #include "heap.h"
  15 #include "debug.h"
  16 #include "thread.h"
  17
  18
  19 /***********************************************************************
  20  *           InitializeCriticalSection   (KERNEL32.472) (NTDLL.406)
  21  */
  22 void WINAPI InitializeCriticalSection( CRITICAL_SECTION *crit )
  23 {
  24     crit->LockCount      = -1;
  25     crit->RecursionCount = 0;
  26     crit->OwningThread   = 0;
  27     crit->LockSemaphore  = 0;
  28     crit->LockSemaphore  = CreateSemaphoreA( NULL, 0, 1, NULL );
  29     crit->Reserved       = (DWORD)-1;
  30 }
  31
  32
  33 /***********************************************************************
  34  *           DeleteCriticalSection   (KERNEL32.185) (NTDLL.327)
  35  */
  36 void WINAPI DeleteCriticalSection( CRITICAL_SECTION *crit )
  37 {
  38     if (crit->LockSemaphore)
  39     {
  40         if (crit->RecursionCount)  /* Should not happen */
  41             MSG("Deleting owned critical section (%p)\n", crit );
  42         crit->LockCount      = -1;
  43         crit->RecursionCount = 0;
  44         crit->OwningThread   = 0;
  45         CloseHandle( crit->LockSemaphore );
  46         crit->LockSemaphore  = 0;
  47     }
  48 }
  49
  50
  51 /***********************************************************************
  52  *           EnterCriticalSection   (KERNEL32.195) (NTDLL.344)
  53  */
  54 void WINAPI EnterCriticalSection( CRITICAL_SECTION *crit )
  55 {
  56     if (!crit->LockSemaphore)
  57     {
  58         FIXME(win32,"entering uninitialized section(%p)?\n",crit);
  59         InitializeCriticalSection(crit);
  60     }
  61     if (InterlockedIncrement( &crit->LockCount ))
  62     {
  63         if (crit->OwningThread == GetCurrentThreadId())
  64         {
  65             crit->RecursionCount++;
  66             return;
  67         }
  68         /* Now wait for it */
  69         /* FIXME: should set a timeout and raise an exception */
  70         WaitForSingleObject( crit->LockSemaphore, INFINITE );
  71     }
  72     crit->OwningThread   = GetCurrentThreadId();
  73     crit->RecursionCount = 1;
  74 }
  75
  76
  77 /***********************************************************************
  78  *           TryEnterCriticalSection   (KERNEL32.898) (NTDLL.969)
  79  */
  80 BOOL WINAPI TryEnterCriticalSection( CRITICAL_SECTION *crit )
  81 {
  82     if (InterlockedIncrement( &crit->LockCount ))
  83     {
  84         if (crit->OwningThread == GetCurrentThreadId())
  85         {
  86             crit->RecursionCount++;
  87             return TRUE;
  88         }
  89         /* FIXME: this doesn't work */
  90         InterlockedDecrement( &crit->LockCount );
  91         return FALSE;
  92     }
  93     crit->OwningThread   = GetCurrentThreadId();
  94     crit->RecursionCount = 1;
  95     return TRUE;
  96 }
  97
  98
  99 /***********************************************************************
 100  *           LeaveCriticalSection   (KERNEL32.494) (NTDLL.426)
 101  */
 102 void WINAPI LeaveCriticalSection( CRITICAL_SECTION *crit )
 103 {
 104     if (crit->OwningThread != GetCurrentThreadId()) return;
 105
 106     if (--crit->RecursionCount)
 107     {
 108         InterlockedDecrement( &crit->LockCount );
 109         return;
 110     }
 111     crit->OwningThread = 0;
 112     if (InterlockedDecrement( &crit->LockCount ) >= 0)
 113     {
 114         /* Someone is waiting */
 115         ReleaseSemaphore( crit->LockSemaphore, 1, NULL );
 116     }
 117 }
 118
 119
 120 /***********************************************************************
 121  *           MakeCriticalSectionGlobal   (KERNEL32.515)
 122  */
 123 void WINAPI MakeCriticalSectionGlobal( CRITICAL_SECTION *crit )
 124 {
 125     crit->LockSemaphore = ConvertToGlobalHandle( crit->LockSemaphore );
 126 }
 127
 128
 129 /***********************************************************************
 130  *           ReinitializeCriticalSection   (KERNEL32.581)
 131  */
 132 void WINAPI ReinitializeCriticalSection( CRITICAL_SECTION *crit )
 133 {
 134     DeleteCriticalSection( crit );
 135     InitializeCriticalSection( crit );
 136 }