incubator-nuttx/sched/signal/sig_queue.c

196 lines
6.5 KiB
C

/****************************************************************************
* sched/signal/sig_queue.c
*
* Copyright (C) 2007-2009, 2013, 2017 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 <nuttx/compiler.h>
#include <signal.h>
#include <debug.h>
#include <sched.h>
#include <errno.h>
#include <nuttx/signal.h>
#include "sched/sched.h"
#include "signal/signal.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxsig_queue
*
* Description:
* This function sends the signal specified by signo with the signal
* parameter value to the process specified by pid.
*
* If the receiving process has the signal blocked via the sigprocmask,
* the signal will pend until it is unmasked. Only one pending signal (per
* signo) is retained. This is consistent with POSIX which states, "If
* a subsequent occurrence of a pending signal is generated, it is
* implementation defined as to whether the signal is delivered more than
* once.
*
* This is an internal OS interface. It is functionally equivalent to
* sigqueue() except that it does not modify the errno value.
*
* Input Parameters:
* pid - Process ID of task to receive signal
* signo - Signal number
* value - Value to pass to task with signal
*
* Returned Value:
* This is an internal OS interface and should not be used by applications.
* It follows the NuttX internal error return policy: Zero (OK) is
* returned on success. A negated errno value is returned on failure.
*
* EGAIN - The limit of signals which may be queued has been reached.
* EINVAL - sig was invalid.
* EPERM - The process does not have permission to send the
* signal to the receiving process.
* ESRCH - No process has a PID matching pid.
*
****************************************************************************/
#ifdef CONFIG_CAN_PASS_STRUCTS
int nxsig_queue (int pid, int signo, union sigval value)
#else
int nxsig_queue(int pid, int signo, void *sival_ptr)
#endif
{
#ifdef CONFIG_SCHED_HAVE_PARENT
FAR struct tcb_s *rtcb = this_task();
#endif
siginfo_t info;
int ret;
#ifdef CONFIG_CAN_PASS_STRUCTS
sinfo("pid=0x%08x signo=%d value=%d\n", pid, signo, value.sival_int);
#else
sinfo("pid=0x%08x signo=%d value=%p\n", pid, signo, sival_ptr);
#endif
/* Sanity checks */
if (!GOOD_SIGNO(signo))
{
return -EINVAL;
}
/* Create the siginfo structure */
info.si_signo = signo;
info.si_code = SI_QUEUE;
info.si_errno = OK;
#ifdef CONFIG_CAN_PASS_STRUCTS
info.si_value = value;
#else
info.si_value.sival_ptr = sival_ptr;
#endif
#ifdef CONFIG_SCHED_HAVE_PARENT
info.si_pid = rtcb->pid;
info.si_status = OK;
#endif
/* Send the signal */
sched_lock();
ret = nxsig_dispatch(pid, &info);
sched_unlock();
return ret;
}
/****************************************************************************
* Name: sigqueue
*
* Description:
* This function sends the signal specified by signo with the signal
* parameter value to the process specified by pid.
*
* If the receiving process has the signal blocked via the sigprocmask,
* the signal will pend until it is unmasked. Only one pending signal (per
* signo) is retained. This is consistent with POSIX which states, "If
* a subsequent occurrence of a pending signal is generated, it is
* implementation defined as to whether the signal is delivered more than
* once."
*
* Input Parameters:
* pid - Process ID of task to receive signal
* signo - Signal number
* value - Value to pass to task with signal
*
* Returned Value:
* On success (at least one signal was sent), zero (OK) is returned. On
* any failure, -1 (ERROR) is returned and errno varaible is set
* appropriately:
*
* EGAIN - The limit of signals which may be queued has been reached.
* EINVAL - sig was invalid.
* EPERM - The process does not have permission to send the
* signal to the receiving process.
* ESRCH - No process has a PID matching pid.
*
****************************************************************************/
#ifdef CONFIG_CAN_PASS_STRUCTS
int sigqueue (int pid, int signo, union sigval value)
#else
int sigqueue(int pid, int signo, void *sival_ptr)
#endif
{
int ret;
/* Let nxsig_queue() do all of the real work */
#ifdef CONFIG_CAN_PASS_STRUCTS
ret = nxsig_queue(pid, signo, value);
#else
ret = nxsig_queue(pid, signo, sival_ptr);
#endif
if (ret < 0)
{
set_errno(-ret);
ret = ERROR;
}
return ret;
}