rom/exec/addsemaphore.c

   1 /*
   2     Copyright © 1995-2017, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Add a semaphore to the public list of semaphores.
   6     Lang: english
   7 */
   8
   9 #include <exec/semaphores.h>
  10 #include <proto/exec.h>
  11
  12 #include "exec_intern.h"
  13 #include "exec_debug.h"
  14
  15 /*****************************************************************************
  16
  17     NAME */
  18
  19         AROS_LH1(void, AddSemaphore,
  20
  21 /*  SYNOPSIS */
  22         AROS_LHA(struct SignalSemaphore *, sigSem, A1),
  23
  24 /*  LOCATION */
  25         struct ExecBase *, SysBase, 100, Exec)
  26
  27 /*  FUNCTION
  28         Adds a semaphore to the system public semaphore list. Since the
  29         semaphore gets initialized by this function it must be free at
  30         this time. Also the ln_Name field must be set.
  31
  32     INPUTS
  33         sigSem - Pointer to semaphore structure
  34
  35     RESULT
  36
  37     NOTES
  38         Semaphores are shared between the tasks that use them and must
  39         therefore lie in public (or at least shared) memory.
  40
  41     EXAMPLE
  42
  43     BUGS
  44
  45     SEE ALSO
  46
  47     INTERNALS
  48
  49 *****************************************************************************/
  50 {
  51     AROS_LIBFUNC_INIT
  52
  53     /* Initialize semaphore */
  54     InitSemaphore(sigSem);
  55
  56     /* Arbitrate for the semaphore list */
  57     Forbid();
  58 #if defined(__AROSEXEC_SMP__)
  59     EXEC_SPINLOCK_LOCK(&PrivExecBase(SysBase)->SemListSpinLock, NULL, SPINLOCK_MODE_WRITE);
  60 #endif
  61     /* Add the semaphore */
  62     Enqueue(&SysBase->SemaphoreList,&sigSem->ss_Link);
  63 #if defined(__AROSEXEC_SMP__)
  64     EXEC_SPINLOCK_UNLOCK(&PrivExecBase(SysBase)->SemListSpinLock);
  65 #endif
  66     /* All done. */
  67     Permit();
  68
  69     AROS_LIBFUNC_EXIT
  70 } /* AddSemaphore */
  71