incubator-nuttx/sched/signal/sig_tgkill.c

137 lines
4.1 KiB
C

/****************************************************************************
* sched/signal/sig_tgkill.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <signal.h>
#include <errno.h>
#include <nuttx/sched.h>
#include <nuttx/signal.h>
#include "sched/sched.h"
#include "signal/signal.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tgkill
*
* Description:
* The tgkill() system call can be used to send any signal to a thread.
* See kill() for further information as this is just a simple wrapper
* around the kill() function.
*
* Input Parameters:
* gid - The id of the task to receive the signal.
* tid - The id of the thread to receive the signal. Only positive,
* non-zero values of 'tid' are supported.
* signo - The signal number to send. If 'signo' is zero, no signal is
* sent, but all error checking is performed.
*
* Returned Value:
* On success the signal was send and zero is returned. On error -1 is
* returned, and errno is set one of the following error numbers:
*
* EINVAL An invalid signal was specified.
* EPERM The thread does not have permission to send the
* signal to the target thread.
* ESRCH No thread could be found corresponding to that
* specified by the given thread ID
* ENOSYS Do not support sending signals to process groups.
*
****************************************************************************/
int tgkill(pid_t pid, pid_t tid, int signo)
{
#ifdef HAVE_GROUP_MEMBERS
/* If group members are supported then tgkill() differs from kill().
* kill(), in this case, must follow the POSIX rules for delivery of
* signals in the group environment. Otherwise, kill(), like tgkill()
* will just deliver the signal to the thread ID it is requested to use.
*/
#ifdef CONFIG_SCHED_HAVE_PARENT
FAR struct tcb_s *rtcb = this_task();
#endif
FAR struct tcb_s *stcb;
siginfo_t info;
int ret;
/* Make sure that the signal is valid */
if (!GOOD_SIGNO(signo))
{
ret = -EINVAL;
goto errout;
}
/* Create the siginfo structure */
info.si_signo = signo;
info.si_code = SI_USER;
info.si_errno = EINTR;
info.si_value.sival_ptr = NULL;
#ifdef CONFIG_SCHED_HAVE_PARENT
info.si_pid = rtcb->pid;
info.si_status = OK;
#endif
/* Get the TCB associated with the thread */
stcb = nxsched_get_tcb(tid);
if (!stcb)
{
ret = -ESRCH;
goto errout;
}
/* Dispatch the signal to thread, bypassing normal task group thread
* dispatch rules.
*/
ret = nxsig_tcbdispatch(stcb, &info);
if (ret < 0)
{
goto errout;
}
return OK;
errout:
set_errno(-ret);
return ERROR;
#else
/* If group members are not supported then tgkill is basically the
* same as kill() other than the sign of the returned value.
*/
return kill(tid, signo);
#endif
}