/****************************************************************************
* sched/sig_procmask.c
*
* Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <unistd.h>
#include <signal.h>
#include <time.h>
#include <wdog.h>
#include <assert.h>
#include <debug.h>
#include <sched.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include "os_internal.h"
#include "sig_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Type Declarations
****************************************************************************/
/****************************************************************************
* Global Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sigprocmask
*
* Description:
* This function allows the calling process to examine and/or change its
* signal mask. If the 'set' is not NULL, then it points to a set of
* signals to be used to change the currently blocked set. The value of
* 'how' indicates the manner in which the set is changed.
*
* If there any pending unblocked signals after the call to sigprocmask(),
* those signals will be delivered before sigprocmask() returns.
*
* If sigprocmask() fails, the signal mask of the process is not changed
* by this function call.
*
* Parameters:
* how - How the signal mast will be changed:
* SIG_BLOCK - The resulting set is the union of the current set
* and the signal set pointed to by 'set'.
* SIG_UNBLOCK - The resulting set is the intersection of the current
* set and the complement of the signal set pointed to
* by 'set'.
* SIG_SETMASK - The resulting set is the signal set pointed to by
* 'set'.
* set - Location of the new signal mask
* oset - Location to store the old signal mask
*
* Return Value:
* 0 (OK), or -1 (ERROR) if how is invalid.
*
* Assumptions:
*
****************************************************************************/
int sigprocmask(int how, FAR const sigset_t *set, FAR sigset_t *oset)
{
FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head;
sigset_t oldsigprocmask;
irqstate_t saved_state;
int ret = OK;
sched_lock();
/* Return the old signal mask if requested */
oldsigprocmask = rtcb->sigprocmask;
if (oset)
{
*oset = oldsigprocmask;
}
/* Modify the current signal mask if so requested */
if (set)
{
/* Some of these operations are non-atomic. We need to protect
* ourselves from attempts to process signals from interrupts
*/
saved_state = irqsave();
/* Okay, determine what we are supposed to do */
switch (how)
{
/* The resulting set is the union of the current set and the
* signal set pointed to by set.
*/
case SIG_BLOCK:
rtcb->sigprocmask |= *set;
break;
/* The resulting set is the intersection of the current set and
* the complement of the signal set pointed to by _set.
*/
case SIG_UNBLOCK:
rtcb->sigprocmask &= ~(*set);
break;
/* The resulting set is the signal set pointed to by set. */
case SIG_SETMASK:
rtcb->sigprocmask = *set;
break;
default:
ret = ERROR;
break;
}
irqrestore(saved_state);
/* Now, process any pending signals that were just unmasked */
sig_unmaskpendingsignal();
}
sched_unlock();
return ret;
}
