scheduler/semaphore.c

   1 /*
   2  * Win32 semaphores
   3  *
   4  * Copyright 1998 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <string.h>
   9 #include "winerror.h"
  10 #include "heap.h"
  11 #include "server/request.h"
  12 #include "server.h"
  13
  14
  15 /***********************************************************************
  16  *           CreateSemaphore32A   (KERNEL32.174)
  17  */
  18 HANDLE WINAPI CreateSemaphoreA( SECURITY_ATTRIBUTES *sa, LONG initial,
  19                                     LONG max, LPCSTR name )
  20 {
  21     struct create_semaphore_request req;
  22     struct create_semaphore_reply reply;
  23     int len = name ? strlen(name) + 1 : 0;
  24
  25     /* Check parameters */
  26
  27     if ((max <= 0) || (initial < 0) || (initial > max))
  28     {
  29         SetLastError( ERROR_INVALID_PARAMETER );
  30         return 0;
  31     }
  32
  33     req.initial = (unsigned int)initial;
  34     req.max     = (unsigned int)max;
  35     req.inherit = (sa && (sa->nLength>=sizeof(*sa)) && sa->bInheritHandle);
  36
  37     CLIENT_SendRequest( REQ_CREATE_SEMAPHORE, -1, 2, &req, sizeof(req), name, len );
  38     SetLastError(0);
  39     CLIENT_WaitSimpleReply( &reply, sizeof(reply), NULL );
  40     if (reply.handle == -1) return 0;
  41     return reply.handle;
  42 }
  43
  44
  45 /***********************************************************************
  46  *           CreateSemaphore32W   (KERNEL32.175)
  47  */
  48 HANDLE WINAPI CreateSemaphoreW( SECURITY_ATTRIBUTES *sa, LONG initial,
  49                                     LONG max, LPCWSTR name )
  50 {
  51     LPSTR nameA = HEAP_strdupWtoA( GetProcessHeap(), 0, name );
  52     HANDLE ret = CreateSemaphoreA( sa, initial, max, nameA );
  53     if (nameA) HeapFree( GetProcessHeap(), 0, nameA );
  54     return ret;
  55 }
  56
  57
  58 /***********************************************************************
  59  *           OpenSemaphore32A   (KERNEL32.545)
  60  */
  61 HANDLE WINAPI OpenSemaphoreA( DWORD access, BOOL inherit, LPCSTR name )
  62 {
  63     struct open_named_obj_request req;
  64     struct open_named_obj_reply reply;
  65     int len = name ? strlen(name) + 1 : 0;
  66
  67     req.type    = OPEN_SEMAPHORE;
  68     req.access  = access;
  69     req.inherit = inherit;
  70     CLIENT_SendRequest( REQ_OPEN_NAMED_OBJ, -1, 2, &req, sizeof(req), name, len );
  71     CLIENT_WaitSimpleReply( &reply, sizeof(reply), NULL );
  72     if (reply.handle == -1) return 0; /* must return 0 on failure, not -1 */
  73     return reply.handle;
  74 }
  75
  76
  77 /***********************************************************************
  78  *           OpenSemaphore32W   (KERNEL32.546)
  79  */
  80 HANDLE WINAPI OpenSemaphoreW( DWORD access, BOOL inherit, LPCWSTR name )
  81 {
  82     LPSTR nameA = HEAP_strdupWtoA( GetProcessHeap(), 0, name );
  83     HANDLE ret = OpenSemaphoreA( access, inherit, nameA );
  84     if (nameA) HeapFree( GetProcessHeap(), 0, nameA );
  85     return ret;
  86 }
  87
  88
  89 /***********************************************************************
  90  *           ReleaseSemaphore   (KERNEL32.583)
  91  */
  92 BOOL WINAPI ReleaseSemaphore( HANDLE handle, LONG count, LONG *previous )
  93 {
  94     struct release_semaphore_request req;
  95     struct release_semaphore_reply reply;
  96
  97     if (count < 0)
  98     {
  99         SetLastError( ERROR_INVALID_PARAMETER );
 100         return FALSE;
 101     }
 102     req.handle = handle;
 103     req.count  = (unsigned int)count;
 104     CLIENT_SendRequest( REQ_RELEASE_SEMAPHORE, -1, 1, &req, sizeof(req) );
 105     if (CLIENT_WaitSimpleReply( &reply, sizeof(reply), NULL )) return FALSE;
 106     if (previous) *previous = reply.prev_count;
 107     return TRUE;
 108 }