Net2/usr/src/sys/kern/kern_sig.c
/*
* Copyright (c) 1982, 1986, 1989, 1991 Regents of the University of California.
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)kern_sig.c 7.35 (Berkeley) 6/28/91
*/
#define SIGPROP /* include signal properties table */
#include "param.h"
#include "signalvar.h"
#include "resourcevar.h"
#include "namei.h"
#include "vnode.h"
#include "proc.h"
#include "systm.h"
#include "timeb.h"
#include "times.h"
#include "buf.h"
#include "seg.h"
#include "acct.h"
#include "file.h"
#include "kernel.h"
#include "wait.h"
#include "ktrace.h"
#include "machine/cpu.h"
#include "vm/vm.h"
#include "kinfo_proc.h"
#include "user.h" /* for coredump */
/*
* Can process p, with pcred pc, send the signal signo to process q?
*/
#define CANSIGNAL(p, pc, q, signo) \
((pc)->pc_ucred->cr_uid == 0 || \
(pc)->p_ruid == (q)->p_cred->p_ruid || \
(pc)->pc_ucred->cr_uid == (q)->p_cred->p_ruid || \
(pc)->p_ruid == (q)->p_ucred->cr_uid || \
(pc)->pc_ucred->cr_uid == (q)->p_ucred->cr_uid || \
((signo) == SIGCONT && (q)->p_session == (p)->p_session))
/* ARGSUSED */
sigaction(p, uap, retval)
struct proc *p;
register struct args {
int signo;
struct sigaction *nsa;
struct sigaction *osa;
} *uap;
int *retval;
{
struct sigaction vec;
register struct sigaction *sa;
register struct sigacts *ps = p->p_sigacts;
register int sig;
int bit, error;
sig = uap->signo;
if (sig <= 0 || sig >= NSIG || sig == SIGKILL || sig == SIGSTOP)
return (EINVAL);
sa = &vec;
if (uap->osa) {
sa->sa_handler = ps->ps_sigact[sig];
sa->sa_mask = ps->ps_catchmask[sig];
bit = sigmask(sig);
sa->sa_flags = 0;
if ((ps->ps_sigonstack & bit) != 0)
sa->sa_flags |= SA_ONSTACK;
if ((ps->ps_sigintr & bit) == 0)
sa->sa_flags |= SA_RESTART;
if (p->p_flag & SNOCLDSTOP)
sa->sa_flags |= SA_NOCLDSTOP;
if (error = copyout((caddr_t)sa, (caddr_t)uap->osa,
sizeof (vec)))
return (error);
}
if (uap->nsa) {
if (error = copyin((caddr_t)uap->nsa, (caddr_t)sa,
sizeof (vec)))
return (error);
setsigvec(p, sig, sa);
}
return (0);
}
setsigvec(p, sig, sa)
register struct proc *p;
int sig;
register struct sigaction *sa;
{
register struct sigacts *ps = p->p_sigacts;
register int bit;
bit = sigmask(sig);
/*
* Change setting atomically.
*/
(void) splhigh();
ps->ps_sigact[sig] = sa->sa_handler;
ps->ps_catchmask[sig] = sa->sa_mask &~ sigcantmask;
if ((sa->sa_flags & SA_RESTART) == 0)
ps->ps_sigintr |= bit;
else
ps->ps_sigintr &= ~bit;
if (sa->sa_flags & SA_ONSTACK)
ps->ps_sigonstack |= bit;
else
ps->ps_sigonstack &= ~bit;
if (sig == SIGCHLD) {
if (sa->sa_flags & SA_NOCLDSTOP)
p->p_flag |= SNOCLDSTOP;
else
p->p_flag &= ~SNOCLDSTOP;
}
/*
* Set bit in p_sigignore for signals that are set to SIG_IGN,
* and for signals set to SIG_DFL where the default is to ignore.
* However, don't put SIGCONT in p_sigignore,
* as we have to restart the process.
*/
if (sa->sa_handler == SIG_IGN ||
(sigprop[sig] & SA_IGNORE && sa->sa_handler == SIG_DFL)) {
p->p_sig &= ~bit; /* never to be seen again */
if (sig != SIGCONT)
p->p_sigignore |= bit; /* easier in psignal */
p->p_sigcatch &= ~bit;
} else {
p->p_sigignore &= ~bit;
if (sa->sa_handler == SIG_DFL)
p->p_sigcatch &= ~bit;
else
p->p_sigcatch |= bit;
}
(void) spl0();
}
/*
* Initialize signal state for process 0;
* set to ignore signals that are ignored by default.
*/
void
siginit(p)
struct proc *p;
{
register int i;
for (i = 0; i < NSIG; i++)
if (sigprop[i] & SA_IGNORE && i != SIGCONT)
p->p_sigignore |= sigmask(i);
}
/*
* Reset signals for an exec of the specified process.
*/
void
execsigs(p)
register struct proc *p;
{
register struct sigacts *ps = p->p_sigacts;
register int nc, mask;
/*
* Reset caught signals. Held signals remain held
* through p_sigmask (unless they were caught,
* and are now ignored by default).
*/
while (p->p_sigcatch) {
nc = ffs((long)p->p_sigcatch);
mask = sigmask(nc);
p->p_sigcatch &= ~mask;
if (sigprop[nc] & SA_IGNORE) {
if (nc != SIGCONT)
p->p_sigignore |= mask;
p->p_sig &= ~mask;
}
ps->ps_sigact[nc] = SIG_DFL;
}
/*
* Reset stack state to the user stack.
* Clear set of signals caught on the signal stack.
*/
ps->ps_onstack = 0;
ps->ps_sigsp = 0;
ps->ps_sigonstack = 0;
}
/*
* Manipulate signal mask.
* Note that we receive new mask, not pointer,
* and return old mask as return value;
* the library stub does the rest.
*/
sigprocmask(p, uap, retval)
register struct proc *p;
struct args {
int how;
sigset_t mask;
} *uap;
int *retval;
{
int error = 0;
*retval = p->p_sigmask;
(void) splhigh();
switch (uap->how) {
case SIG_BLOCK:
p->p_sigmask |= uap->mask &~ sigcantmask;
break;
case SIG_UNBLOCK:
p->p_sigmask &= ~uap->mask;
break;
case SIG_SETMASK:
p->p_sigmask = uap->mask &~ sigcantmask;
break;
default:
error = EINVAL;
break;
}
(void) spl0();
return (error);
}
/* ARGSUSED */
sigpending(p, uap, retval)
struct proc *p;
void *uap;
int *retval;
{
*retval = p->p_sig;
return (0);
}
#ifdef COMPAT_43
/*
* Generalized interface signal handler, 4.3-compatible.
*/
/* ARGSUSED */
osigvec(p, uap, retval)
struct proc *p;
register struct args {
int signo;
struct sigvec *nsv;
struct sigvec *osv;
} *uap;
int *retval;
{
struct sigvec vec;
register struct sigacts *ps = p->p_sigacts;
register struct sigvec *sv;
register int sig;
int bit, error;
sig = uap->signo;
if (sig <= 0 || sig >= NSIG || sig == SIGKILL || sig == SIGSTOP)
return (EINVAL);
sv = &vec;
if (uap->osv) {
*(sig_t *)&sv->sv_handler = ps->ps_sigact[sig];
sv->sv_mask = ps->ps_catchmask[sig];
bit = sigmask(sig);
sv->sv_flags = 0;
if ((ps->ps_sigonstack & bit) != 0)
sv->sv_flags |= SV_ONSTACK;
if ((ps->ps_sigintr & bit) != 0)
sv->sv_flags |= SV_INTERRUPT;
if (p->p_flag & SNOCLDSTOP)
sv->sv_flags |= SA_NOCLDSTOP;
if (error = copyout((caddr_t)sv, (caddr_t)uap->osv,
sizeof (vec)))
return (error);
}
if (uap->nsv) {
if (error = copyin((caddr_t)uap->nsv, (caddr_t)sv,
sizeof (vec)))
return (error);
sv->sv_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
setsigvec(p, sig, (struct sigaction *)sv);
}
return (0);
}
osigblock(p, uap, retval)
register struct proc *p;
struct args {
int mask;
} *uap;
int *retval;
{
(void) splhigh();
*retval = p->p_sigmask;
p->p_sigmask |= uap->mask &~ sigcantmask;
(void) spl0();
return (0);
}
osigsetmask(p, uap, retval)
struct proc *p;
struct args {
int mask;
} *uap;
int *retval;
{
(void) splhigh();
*retval = p->p_sigmask;
p->p_sigmask = uap->mask &~ sigcantmask;
(void) spl0();
return (0);
}
#endif
/*
* Suspend process until signal, providing mask to be set
* in the meantime. Note nonstandard calling convention:
* libc stub passes mask, not pointer, to save a copyin.
*/
/* ARGSUSED */
sigsuspend(p, uap, retval)
register struct proc *p;
struct args {
sigset_t mask;
} *uap;
int *retval;
{
register struct sigacts *ps = p->p_sigacts;
/*
* When returning from sigpause, we want
* the old mask to be restored after the
* signal handler has finished. Thus, we
* save it here and mark the proc structure
* to indicate this (should be in sigacts).
*/
ps->ps_oldmask = p->p_sigmask;
ps->ps_flags |= SA_OLDMASK;
p->p_sigmask = uap->mask &~ sigcantmask;
(void) tsleep((caddr_t) ps, PPAUSE|PCATCH, "pause", 0);
/* always return EINTR rather than ERESTART... */
return (EINTR);
}
/* ARGSUSED */
sigstack(p, uap, retval)
struct proc *p;
register struct args {
struct sigstack *nss;
struct sigstack *oss;
} *uap;
int *retval;
{
struct sigstack ss;
int error = 0;
if (uap->oss && (error = copyout((caddr_t)&p->p_sigacts->ps_sigstack,
(caddr_t)uap->oss, sizeof (struct sigstack))))
return (error);
if (uap->nss && (error = copyin((caddr_t)uap->nss, (caddr_t)&ss,
sizeof (ss))) == 0)
p->p_sigacts->ps_sigstack = ss;
return (error);
}
/* ARGSUSED */
kill(cp, uap, retval)
register struct proc *cp;
register struct args {
int pid;
int signo;
} *uap;
int *retval;
{
register struct proc *p;
register struct pcred *pc = cp->p_cred;
if ((unsigned) uap->signo >= NSIG)
return (EINVAL);
if (uap->pid > 0) {
/* kill single process */
p = pfind(uap->pid);
if (p == 0)
return (ESRCH);
if (!CANSIGNAL(cp, pc, p, uap->signo))
return (EPERM);
if (uap->signo)
psignal(p, uap->signo);
return (0);
}
switch (uap->pid) {
case -1: /* broadcast signal */
return (killpg1(cp, uap->signo, 0, 1));
case 0: /* signal own process group */
return (killpg1(cp, uap->signo, 0, 0));
default: /* negative explicit process group */
return (killpg1(cp, uap->signo, -uap->pid, 0));
}
/* NOTREACHED */
}
#ifdef COMPAT_43
/* ARGSUSED */
okillpg(p, uap, retval)
struct proc *p;
register struct args {
int pgid;
int signo;
} *uap;
int *retval;
{
if ((unsigned) uap->signo >= NSIG)
return (EINVAL);
return (killpg1(p, uap->signo, uap->pgid, 0));
}
#endif
/*
* Common code for kill process group/broadcast kill.
* cp is calling process.
*/
killpg1(cp, signo, pgid, all)
register struct proc *cp;
int signo, pgid, all;
{
register struct proc *p;
register struct pcred *pc = cp->p_cred;
struct pgrp *pgrp;
int nfound = 0;
if (all)
/*
* broadcast
*/
for (p = allproc; p != NULL; p = p->p_nxt) {
if (p->p_pid <= 1 || p->p_flag&SSYS ||
p == cp || !CANSIGNAL(cp, pc, p, signo))
continue;
nfound++;
if (signo)
psignal(p, signo);
}
else {
if (pgid == 0)
/*
* zero pgid means send to my process group.
*/
pgrp = cp->p_pgrp;
else {
pgrp = pgfind(pgid);
if (pgrp == NULL)
return (ESRCH);
}
for (p = pgrp->pg_mem; p != NULL; p = p->p_pgrpnxt) {
if (p->p_pid <= 1 || p->p_flag&SSYS ||
p->p_stat == SZOMB || !CANSIGNAL(cp, pc, p, signo))
continue;
nfound++;
if (signo)
psignal(p, signo);
}
}
return (nfound ? 0 : ESRCH);
}
/*
* Send the specified signal to
* all processes with 'pgid' as
* process group.
*/
void
gsignal(pgid, sig)
int pgid, sig;
{
struct pgrp *pgrp;
if (pgid && (pgrp = pgfind(pgid)))
pgsignal(pgrp, sig, 0);
}
/*
* Send sig to every member of a process group.
* If checktty is 1, limit to members which have a controlling
* terminal.
*/
void
pgsignal(pgrp, sig, checkctty)
struct pgrp *pgrp;
int sig, checkctty;
{
register struct proc *p;
if (pgrp)
for (p = pgrp->pg_mem; p != NULL; p = p->p_pgrpnxt)
if (checkctty == 0 || p->p_flag&SCTTY)
psignal(p, sig);
}
/*
* Send a signal caused by a trap to the current process.
* If it will be caught immediately, deliver it with correct code.
* Otherwise, post it normally.
*/
void
trapsignal(p, sig, code)
struct proc *p;
register int sig;
unsigned code;
{
register struct sigacts *ps = p->p_sigacts;
int mask;
mask = sigmask(sig);
if ((p->p_flag & STRC) == 0 && (p->p_sigcatch & mask) != 0 &&
(p->p_sigmask & mask) == 0) {
p->p_stats->p_ru.ru_nsignals++;
#ifdef KTRACE
if (KTRPOINT(p, KTR_PSIG))
ktrpsig(p->p_tracep, sig, ps->ps_sigact[sig],
p->p_sigmask, code);
#endif
sendsig(ps->ps_sigact[sig], sig, p->p_sigmask, code);
p->p_sigmask |= ps->ps_catchmask[sig] | mask;
} else {
ps->ps_code = code; /* XXX for core dump/debugger */
psignal(p, sig);
}
}
/*
* Send the specified signal to the specified process.
* If the signal has an action, the action is usually performed
* by the target process rather than the caller; we simply add
* the signal to the set of pending signals for the process.
* Exceptions:
* o When a stop signal is sent to a sleeping process that takes the default
* action, the process is stopped without awakening it.
* o SIGCONT restarts stopped processes (or puts them back to sleep)
* regardless of the signal action (eg, blocked or ignored).
* Other ignored signals are discarded immediately.
*/
void
psignal(p, sig)
register struct proc *p;
register int sig;
{
register int s, prop;
register sig_t action;
int mask;
if ((unsigned)sig >= NSIG || sig == 0)
panic("psignal sig");
mask = sigmask(sig);
prop = sigprop[sig];
/*
* If proc is traced, always give parent a chance.
*/
if (p->p_flag & STRC)
action = SIG_DFL;
else {
/*
* If the signal is being ignored,
* then we forget about it immediately.
* (Note: we don't set SIGCONT in p_sigignore,
* and if it is set to SIG_IGN,
* action will be SIG_DFL here.)
*/
if (p->p_sigignore & mask)
return;
if (p->p_sigmask & mask)
action = SIG_HOLD;
else if (p->p_sigcatch & mask)
action = SIG_CATCH;
else
action = SIG_DFL;
}
if (p->p_nice > NZERO && (sig == SIGKILL ||
sig == SIGTERM && (p->p_flag&STRC || action != SIG_DFL)))
p->p_nice = NZERO;
if (prop & SA_CONT)
p->p_sig &= ~stopsigmask;
if (prop & SA_STOP) {
/*
* If sending a tty stop signal to a member of an orphaned
* process group, discard the signal here if the action
* is default; don't stop the process below if sleeping,
* and don't clear any pending SIGCONT.
*/
if (prop & SA_TTYSTOP && p->p_pgrp->pg_jobc == 0 &&
action == SIG_DFL)
return;
p->p_sig &= ~contsigmask;
}
p->p_sig |= mask;
/*
* Defer further processing for signals which are held,
* except that stopped processes must be continued by SIGCONT.
*/
if (action == SIG_HOLD && ((prop & SA_CONT) == 0 || p->p_stat != SSTOP))
return;
s = splhigh();
switch (p->p_stat) {
case SSLEEP:
/*
* If process is sleeping uninterruptibly
* we can't interrupt the sleep... the signal will
* be noticed when the process returns through
* trap() or syscall().
*/
if ((p->p_flag & SSINTR) == 0)
goto out;
/*
* Process is sleeping and traced... make it runnable
* so it can discover the signal in issig() and stop
* for the parent.
*/
if (p->p_flag&STRC)
goto run;
/*
* When a sleeping process receives a stop
* signal, process immediately if possible.
* All other (caught or default) signals
* cause the process to run.
*/
if (prop & SA_STOP) {
if (action != SIG_DFL)
goto runfast;
/*
* If a child holding parent blocked,
* stopping could cause deadlock.
*/
if (p->p_flag&SPPWAIT)
goto out;
p->p_sig &= ~mask;
p->p_xstat = sig;
if ((p->p_pptr->p_flag & SNOCLDSTOP) == 0)
psignal(p->p_pptr, SIGCHLD);
stop(p);
goto out;
} else
goto runfast;
/*NOTREACHED*/
case SSTOP:
/*
* If traced process is already stopped,
* then no further action is necessary.
*/
if (p->p_flag&STRC)
goto out;
/*
* Kill signal always sets processes running.
*/
if (sig == SIGKILL)
goto runfast;
if (prop & SA_CONT) {
/*
* If SIGCONT is default (or ignored), we continue
* the process but don't leave the signal in p_sig,
* as it has no further action. If SIGCONT is held,
* continue the process and leave the signal in p_sig.
* If the process catches SIGCONT, let it handle
* the signal itself. If it isn't waiting on
* an event, then it goes back to run state.
* Otherwise, process goes back to sleep state.
*/
if (action == SIG_DFL)
p->p_sig &= ~mask;
if (action == SIG_CATCH)
goto runfast;
if (p->p_wchan == 0)
goto run;
p->p_stat = SSLEEP;
goto out;
}
if (prop & SA_STOP) {
/*
* Already stopped, don't need to stop again.
* (If we did the shell could get confused.)
*/
p->p_sig &= ~mask; /* take it away */
goto out;
}
/*
* If process is sleeping interruptibly, then
* simulate a wakeup so that when it is continued,
* it will be made runnable and can look at the signal.
* But don't setrun the process, leave it stopped.
*/
if (p->p_wchan && p->p_flag & SSINTR)
unsleep(p);
goto out;
default:
/*
* SRUN, SIDL, SZOMB do nothing with the signal,
* other than kicking ourselves if we are running.
* It will either never be noticed, or noticed very soon.
*/
if (p == curproc)
signotify(p);
goto out;
}
/*NOTREACHED*/
runfast:
/*
* Raise priority to at least PUSER.
*/
if (p->p_pri > PUSER)
p->p_pri = PUSER;
run:
setrun(p);
out:
splx(s);
}
/*
* If the current process has a signal to process (should be caught
* or cause termination, should interrupt current syscall),
* return the signal number. Stop signals with default action
* are processed immediately, then cleared; they aren't returned.
* This is checked after each entry to the system for a syscall
* or trap (though this can usually be done without actually calling
* issig by checking the pending signal masks in the CURSIG macro.)
* The normal call sequence is
*
* while (sig = CURSIG(curproc))
* psig(sig);
*/
issig(p)
register struct proc *p;
{
register int sig, mask, prop;
for (;;) {
mask = p->p_sig &~ p->p_sigmask;
if (p->p_flag&SPPWAIT)
mask &= ~stopsigmask;
if (mask == 0) /* no signal to send */
return (0);
sig = ffs((long)mask);
mask = sigmask(sig);
prop = sigprop[sig];
/*
* We should see pending but ignored signals
* only if STRC was on when they were posted.
*/
if (mask & p->p_sigignore && (p->p_flag&STRC) == 0) {
p->p_sig &= ~mask;
continue;
}
if (p->p_flag&STRC && (p->p_flag&SPPWAIT) == 0) {
/*
* If traced, always stop, and stay
* stopped until released by the parent.
*/
p->p_xstat = sig;
psignal(p->p_pptr, SIGCHLD);
do {
stop(p);
swtch();
} while (!procxmt(p) && p->p_flag&STRC);
/*
* If the traced bit got turned off,
* go back up to the top to rescan signals.
* This ensures that p_sig* and ps_sigact
* are consistent.
*/
if ((p->p_flag&STRC) == 0)
continue;
/*
* If parent wants us to take the signal,
* then it will leave it in p->p_xstat;
* otherwise we just look for signals again.
*/
p->p_sig &= ~mask; /* clear the old signal */
sig = p->p_xstat;
if (sig == 0)
continue;
/*
* Put the new signal into p_sig.
* If signal is being masked,
* look for other signals.
*/
mask = sigmask(sig);
p->p_sig |= mask;
if (p->p_sigmask & mask)
continue;
}
/*
* Decide whether the signal should be returned.
* Return the signal's number, or fall through
* to clear it from the pending mask.
*/
switch ((int)p->p_sigacts->ps_sigact[sig]) {
case SIG_DFL:
/*
* Don't take default actions on system processes.
*/
if (p->p_pid <= 1)
break; /* == ignore */
/*
* If there is a pending stop signal to process
* with default action, stop here,
* then clear the signal. However,
* if process is member of an orphaned
* process group, ignore tty stop signals.
*/
if (prop & SA_STOP) {
if (p->p_flag&STRC ||
(p->p_pgrp->pg_jobc == 0 &&
prop & SA_TTYSTOP))
break; /* == ignore */
p->p_xstat = sig;
stop(p);
if ((p->p_pptr->p_flag & SNOCLDSTOP) == 0)
psignal(p->p_pptr, SIGCHLD);
swtch();
break;
} else if (prop & SA_IGNORE) {
/*
* Except for SIGCONT, shouldn't get here.
* Default action is to ignore; drop it.
*/
break; /* == ignore */
} else
return (sig);
/*NOTREACHED*/
case SIG_IGN:
/*
* Masking above should prevent us ever trying
* to take action on an ignored signal other
* than SIGCONT, unless process is traced.
*/
if ((prop & SA_CONT) == 0 && (p->p_flag&STRC) == 0)
printf("issig\n");
break; /* == ignore */
default:
/*
* This signal has an action, let
* psig process it.
*/
return (sig);
}
p->p_sig &= ~mask; /* take the signal! */
}
/* NOTREACHED */
}
/*
* Put the argument process into the stopped
* state and notify the parent via wakeup.
* Signals are handled elsewhere.
* The process must not be on the run queue.
*/
stop(p)
register struct proc *p;
{
p->p_stat = SSTOP;
p->p_flag &= ~SWTED;
wakeup((caddr_t)p->p_pptr);
}
/*
* Take the action for the specified signal
* from the current set of pending signals.
*/
void
psig(sig)
register int sig;
{
register struct proc *p = curproc;
register struct sigacts *ps = p->p_sigacts;
register sig_t action;
int mask, returnmask;
#ifdef DIAGNOSTIC
if (sig == 0)
panic("psig");
#endif
mask = sigmask(sig);
p->p_sig &= ~mask;
action = ps->ps_sigact[sig];
#ifdef KTRACE
if (KTRPOINT(p, KTR_PSIG))
ktrpsig(p->p_tracep, sig, action, ps->ps_flags & SA_OLDMASK ?
ps->ps_oldmask : p->p_sigmask, 0);
#endif
if (action == SIG_DFL) {
/*
* Default action, where the default is to kill
* the process. (Other cases were ignored above.)
*/
sigexit(p, sig);
/* NOTREACHED */
} else {
/*
* If we get here, the signal must be caught.
*/
#ifdef DIAGNOSTIC
if (action == SIG_IGN || (p->p_sigmask & mask))
panic("psig action");
#endif
/*
* Set the new mask value and also defer further
* occurences of this signal.
*
* Special case: user has done a sigpause. Here the
* current mask is not of interest, but rather the
* mask from before the sigpause is what we want
* restored after the signal processing is completed.
*/
(void) splhigh();
if (ps->ps_flags & SA_OLDMASK) {
returnmask = ps->ps_oldmask;
ps->ps_flags &= ~SA_OLDMASK;
} else
returnmask = p->p_sigmask;
p->p_sigmask |= ps->ps_catchmask[sig] | mask;
(void) spl0();
p->p_stats->p_ru.ru_nsignals++;
sendsig(action, sig, returnmask, 0);
}
}
/*
* Force the current process to exit with the specified
* signal, dumping core if appropriate. We bypass the normal
* tests for masked and caught signals, allowing unrecoverable
* failures to terminate the process without changing signal state.
* Mark the accounting record with the signal termination.
* If dumping core, save the signal number for the debugger.
* Calls exit and does not return.
*/
sigexit(p, sig)
register struct proc *p;
int sig;
{
p->p_acflag |= AXSIG;
if (sigprop[sig] & SA_CORE) {
p->p_sigacts->ps_sig = sig;
if (coredump(p) == 0)
sig |= WCOREFLAG;
}
exit(p, W_EXITCODE(0, sig));
/* NOTREACHED */
}
/*
* Create a core dump.
* The file name is "core.progname".
* Core dumps are not created if the process is setuid.
*/
coredump(p)
register struct proc *p;
{
register struct vnode *vp;
register struct pcred *pcred = p->p_cred;
register struct ucred *cred = pcred->pc_ucred;
register struct vmspace *vm = p->p_vmspace;
struct vattr vattr;
int error, error1;
struct nameidata nd;
char name[MAXCOMLEN+6]; /* core.progname */
if (pcred->p_svuid != pcred->p_ruid ||
pcred->p_svgid != pcred->p_rgid)
return (EFAULT);
if (ctob(UPAGES + vm->vm_dsize + vm->vm_ssize) >=
p->p_rlimit[RLIMIT_CORE].rlim_cur)
return (EFAULT);
sprintf(name, "core.%s", p->p_comm);
nd.ni_dirp = name;
nd.ni_segflg = UIO_SYSSPACE;
if (error = vn_open(&nd, p, O_CREAT|FWRITE, 0644))
return (error);
vp = nd.ni_vp;
if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred, p) ||
vattr.va_nlink != 1) {
error = EFAULT;
goto out;
}
VATTR_NULL(&vattr);
vattr.va_size = 0;
VOP_SETATTR(vp, &vattr, cred, p);
p->p_acflag |= ACORE;
bcopy(p, &p->p_addr->u_kproc.kp_proc, sizeof(struct proc));
fill_eproc(p, &p->p_addr->u_kproc.kp_eproc);
#ifdef HPUXCOMPAT
/*
* BLETCH! If we loaded from an HPUX format binary file
* we have to dump an HPUX style user struct so that the
* HPUX debuggers can grok it.
*/
if (p->p_addr->u_pcb.pcb_flags & PCB_HPUXBIN)
error = hpuxdumpu(vp, cred);
else
#endif
error = vn_rdwr(UIO_WRITE, vp, (caddr_t) p->p_addr, ctob(UPAGES),
(off_t)0, UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *) NULL,
p);
if (error == 0)
error = vn_rdwr(UIO_WRITE, vp, vm->vm_daddr,
(int)ctob(vm->vm_dsize), (off_t)ctob(UPAGES), UIO_USERSPACE,
IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p);
if (error == 0)
error = vn_rdwr(UIO_WRITE, vp,
(caddr_t) trunc_page(USRSTACK - ctob(vm->vm_ssize)),
round_page(ctob(vm->vm_ssize)),
(off_t)ctob(UPAGES) + ctob(vm->vm_dsize), UIO_USERSPACE,
IO_NODELOCKED|IO_UNIT, cred, (int *) NULL, p);
out:
VOP_UNLOCK(vp);
error1 = vn_close(vp, FWRITE, cred, p);
if (error == 0)
error = error1;
return (error);
}
/*
* Nonexistent system call-- signal process (may want to handle it).
* Flag error in case process won't see signal immediately (blocked or ignored).
*/
/* ARGSUSED */
nosys(p, args, retval)
struct proc *p;
void *args;
int *retval;
{
psignal(p, SIGSYS);
return (EINVAL);
}