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.h"
  12
  13
  14 /***********************************************************************
  15  *           CreateSemaphore32A   (KERNEL32.174)
  16  */
  17 HANDLE WINAPI CreateSemaphoreA( SECURITY_ATTRIBUTES *sa, LONG initial, LONG max, LPCSTR name )
  18 {
  19     struct create_semaphore_request *req = get_req_buffer();
  20
  21     /* Check parameters */
  22
  23     if ((max <= 0) || (initial < 0) || (initial > max))
  24     {
  25         SetLastError( ERROR_INVALID_PARAMETER );
  26         return 0;
  27     }
  28
  29     req->initial = (unsigned int)initial;
  30     req->max     = (unsigned int)max;
  31     req->inherit = (sa && (sa->nLength>=sizeof(*sa)) && sa->bInheritHandle);
  32     lstrcpynA( req->name, name ? name : "", server_remaining(req->name) );
  33     SetLastError(0);
  34     server_call( REQ_CREATE_SEMAPHORE );
  35     if (req->handle == -1) return 0;
  36     return req->handle;
  37 }
  38
  39
  40 /***********************************************************************
  41  *           CreateSemaphore32W   (KERNEL32.175)
  42  */
  43 HANDLE WINAPI CreateSemaphoreW( SECURITY_ATTRIBUTES *sa, LONG initial,
  44                                     LONG max, LPCWSTR name )
  45 {
  46     LPSTR nameA = HEAP_strdupWtoA( GetProcessHeap(), 0, name );
  47     HANDLE ret = CreateSemaphoreA( sa, initial, max, nameA );
  48     if (nameA) HeapFree( GetProcessHeap(), 0, nameA );
  49     return ret;
  50 }
  51
  52
  53 /***********************************************************************
  54  *           OpenSemaphore32A   (KERNEL32.545)
  55  */
  56 HANDLE WINAPI OpenSemaphoreA( DWORD access, BOOL inherit, LPCSTR name )
  57 {
  58     struct open_semaphore_request *req = get_req_buffer();
  59
  60     req->access  = access;
  61     req->inherit = inherit;
  62     lstrcpynA( req->name, name ? name : "", server_remaining(req->name) );
  63     server_call( REQ_OPEN_SEMAPHORE );
  64     if (req->handle == -1) return 0; /* must return 0 on failure, not -1 */
  65     return req->handle;
  66 }
  67
  68
  69 /***********************************************************************
  70  *           OpenSemaphore32W   (KERNEL32.546)
  71  */
  72 HANDLE WINAPI OpenSemaphoreW( DWORD access, BOOL inherit, LPCWSTR name )
  73 {
  74     LPSTR nameA = HEAP_strdupWtoA( GetProcessHeap(), 0, name );
  75     HANDLE ret = OpenSemaphoreA( access, inherit, nameA );
  76     if (nameA) HeapFree( GetProcessHeap(), 0, nameA );
  77     return ret;
  78 }
  79
  80
  81 /***********************************************************************
  82  *           ReleaseSemaphore   (KERNEL32.583)
  83  */
  84 BOOL WINAPI ReleaseSemaphore( HANDLE handle, LONG count, LONG *previous )
  85 {
  86     struct release_semaphore_request *req = get_req_buffer();
  87
  88     if (count < 0)
  89     {
  90         SetLastError( ERROR_INVALID_PARAMETER );
  91         return FALSE;
  92     }
  93     req->handle = handle;
  94     req->count  = (unsigned int)count;
  95     if (server_call( REQ_RELEASE_SEMAPHORE )) return FALSE;
  96     if (previous) *previous = req->prev_count;
  97     return TRUE;
  98 }