cpukit/posix/src/sigsuspend.c


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/*
 *  3.3.7 Wait for a Signal, P1003.1b-1993, p. 75
 *
 *  COPYRIGHT (c) 1989-2004.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.com/license/LICENSE.
 */

#if HAVE_CONFIG_H
#include "config.h"
#endif

#include <assert.h>
#include <signal.h>
#include <errno.h>

#include <rtems/system.h>
#include <rtems/posix/pthread.h>
#include <rtems/posix/psignal.h>
#include <rtems/seterr.h>

int sigsuspend(
  const sigset_t  *sigmask
)
{
  sigset_t            saved_signals_blocked;
  sigset_t            current_unblocked_signals;
  int                 status;
  POSIX_API_Control  *api;

  api = _Thread_Executing->API_Extensions[ THREAD_API_POSIX ];

  /*
   *  We use SIG_BLOCK and not SIG_SETMASK because there may be
   *  signals which might be pending, which might get caught here.
   *  We want the signals to be caught inside sigtimedwait.
   */
  status = sigprocmask( SIG_BLOCK, sigmask, &saved_signals_blocked );

  current_unblocked_signals = ~(*sigmask);
  status = sigtimedwait( &current_unblocked_signals, NULL, NULL );

  (void) sigprocmask( SIG_SETMASK, &saved_signals_blocked, NULL );

  /*
   * sigtimedwait() returns the signal number while sigsuspend()
   * is supposed to return -1 and EINTR when a signal is caught.
   */
  #if defined(RTEMS_DEBUG)
    assert( status != -1 );
  #endif

  rtems_set_errno_and_return_minus_one( EINTR );
}