/**************************************************************************** * sched/signal/sig_procmask.c * * Copyright (C) 2007-2009, 2014, 2016-2017 Gregory Nutt. All rights * reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include "sched/sched.h" #include "signal/signal.h" /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: nxsig_procmask * * 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 * nxsig_procmask(), those signals will be delivered before * nxsig_procmask() returns. * * If nxsig_procmask() fails, the signal mask of the process is not changed * by this function call. * * This is an internal OS interface. It is functionally equivalent to * sigprocmask() except that it does not modify the errno value. * * 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: * 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. * * EINVAL - The 'how' argument is invalid. * ****************************************************************************/ int nxsig_procmask(int how, FAR const sigset_t *set, FAR sigset_t *oset) { FAR struct tcb_s *rtcb = this_task(); sigset_t oldsigprocmask; irqstate_t flags; 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 != NULL) { /* Some of these operations are non-atomic. We need to protect * ourselves from attempts to process signals from interrupts */ flags = enter_critical_section(); /* 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 = -EINVAL; break; } leave_critical_section(flags); /* Now, process any pending signals that were just unmasked */ nxsig_unmask_pendingsignal(); } sched_unlock(); return ret; } /**************************************************************************** * 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: * This function will return 0 (OK) on success or -1 (ERROR) if how is * invalid. In the latter case, the errno variable will be set to EINVAL. * ****************************************************************************/ int sigprocmask(int how, FAR const sigset_t *set, FAR sigset_t *oset) { int ret; /* Let nxsig_procmask do all of the work */ ret = nxsig_procmask(how, set, oset); if (ret < 0) { set_errno(-ret); ret = ERROR; } return ret; }