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/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley Software License Agreement
* specifies the terms and conditions for redistribution.
*/
/*
* 4.3BSD signal compatibility functions
*
* the implementation interprets signal masks equal to -1 as "all of the
* signals in the signal set", thereby allowing signals with numbers
* above 32 to be blocked when referenced in code such as:
*
* for (i = 0; i < NSIG; i++)
* mask |= sigmask(i)
*/
#include <sys/types.h>
#include <sys/siginfo.h>
#include <ucontext.h>
#include <signal.h>
#include "signal.h"
#include <errno.h>
#include <stdio.h>
#define set2mask(setp) ((setp)->__sigbits[0])
#define mask2set(mask, setp) \
((mask) == -1 ? sigfillset(setp) : sigemptyset(setp), (((setp)->__sigbits[0]) = (mask)))
void (*_siguhandler[NSIG])() = { 0 };
/*
* sigstack is emulated with sigaltstack by guessing an appropriate
* value for the stack size - on machines that have stacks that grow
* upwards, the ss_sp arguments for both functions mean the same thing,
* (the initial stack pointer sigstack() is also the stack base
* sigaltstack()), so a "very large" value should be chosen for the
* stack size - on machines that have stacks that grow downwards, the
* ss_sp arguments mean opposite things, so 0 should be used (hopefully
* these machines don't have hardware stack bounds registers that pay
* attention to sigaltstack()'s size argument.
*/
#ifdef sun
#define SIGSTACKSIZE 0
#endif
/*
* sigvechandler is the real signal handler installed for all
* signals handled in the 4.3BSD compatibility interface - it translates
* SVR4 signal hander arguments into 4.3BSD signal handler arguments
* and then calls the real handler
*/
static void
sigvechandler(int sig, siginfo_t *sip, ucontext_t *ucp)
{
struct sigcontext sc;
int code;
char *addr;
int i, j;
int gwinswitch = 0;
sc.sc_onstack = ((ucp->uc_stack.ss_flags & SS_ONSTACK) != 0);
sc.sc_mask = set2mask(&ucp->uc_sigmask);
/*
* Machine dependent code begins
*/
sc.sc_sp = (int) ucp->uc_mcontext.gregs[UESP];
sc.sc_pc = (int) ucp->uc_mcontext.gregs[EIP];
sc.sc_ps = (int) ucp->uc_mcontext.gregs[EFL];
sc.sc_eax = (int) ucp->uc_mcontext.gregs[EAX];
sc.sc_edx = (int) ucp->uc_mcontext.gregs[EDX];
/*
* Machine dependent code ends
*/
if (sip != NULL)
if ((code = sip->si_code) == BUS_OBJERR)
code = SEGV_MAKE_ERR(sip->si_errno);
if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS)
if (sip != NULL)
addr = (char *)sip->si_addr;
else
addr = SIG_NOADDR;
(*_siguhandler[sig])(sig, code, &sc, addr);
if (sc.sc_onstack)
ucp->uc_stack.ss_flags |= SS_ONSTACK;
else
ucp->uc_stack.ss_flags &= ~SS_ONSTACK;
mask2set(sc.sc_mask, &ucp->uc_sigmask);
/*
* Machine dependent code begins
*/
ucp->uc_mcontext.gregs[UESP] = (int) sc.sc_sp;
ucp->uc_mcontext.gregs[EIP] = (int) sc.sc_pc;
ucp->uc_mcontext.gregs[EFL] = (int) sc.sc_ps;
ucp->uc_mcontext.gregs[EAX] = (int) sc.sc_eax;
ucp->uc_mcontext.gregs[EDX] = (int) sc.sc_edx;
/*
* Machine dependent code ends
*/
setcontext (ucp);
}
int
sigsetmask(int mask)
{
sigset_t oset;
sigset_t nset;
(void) sigprocmask(0, (sigset_t *)0, &nset);
mask2set(mask, &nset);
(void) sigprocmask(SIG_SETMASK, &nset, &oset);
return set2mask(&oset);
}
int
sigblock(int mask)
{
sigset_t oset;
sigset_t nset;
(void) sigprocmask(0, (sigset_t *)0, &nset);
mask2set(mask, &nset);
(void) sigprocmask(SIG_BLOCK, &nset, &oset);
return set2mask(&oset);
}
int
sigpause(int mask)
{
sigset_t set;
(void) sigprocmask(0, (sigset_t *)0, &set);
mask2set(mask, &set);
return (sigsuspend(&set));
}
int
sigvec(int sig, struct sigvec *nvec, struct sigvec *ovec)
{
struct sigaction nact;
struct sigaction oact;
struct sigaction *nactp;
void (*ohandler)(), (*nhandler)();
if (sig <= 0 || sig >= NSIG) {
errno = EINVAL;
return -1;
}
ohandler = _siguhandler[sig];
if (nvec) {
_sigaction(sig, (struct sigaction *)0, &nact);
nhandler = nvec->sv_handler;
_siguhandler[sig] = nhandler;
if (nhandler != SIG_DFL && nhandler != SIG_IGN)
nact.sa_handler = (void (*)())sigvechandler;
else
nact.sa_handler = nhandler;
mask2set(nvec->sv_mask, &nact.sa_mask);
/*
if ( sig == SIGTSTP || sig == SIGSTOP )
nact.sa_handler = SIG_DFL; */
nact.sa_flags = SA_SIGINFO;
if (!(nvec->sv_flags & SV_INTERRUPT))
nact.sa_flags |= SA_RESTART;
if (nvec->sv_flags & SV_RESETHAND)
nact.sa_flags |= SA_RESETHAND;
if (nvec->sv_flags & SV_ONSTACK)
nact.sa_flags |= SA_ONSTACK;
nactp = &nact;
} else
nactp = (struct sigaction *)0;
if (_sigaction(sig, nactp, &oact) < 0) {
_siguhandler[sig] = ohandler;
return -1;
}
if (ovec) {
if (oact.sa_handler == SIG_DFL || oact.sa_handler == SIG_IGN)
ovec->sv_handler = oact.sa_handler;
else
ovec->sv_handler = ohandler;
ovec->sv_mask = set2mask(&oact.sa_mask);
ovec->sv_flags = 0;
if (oact.sa_flags & SA_ONSTACK)
ovec->sv_flags |= SV_ONSTACK;
if (oact.sa_flags & SA_RESETHAND)
ovec->sv_flags |= SV_RESETHAND;
if (!(oact.sa_flags & SA_RESTART))
ovec->sv_flags |= SV_INTERRUPT;
}
return 0;
}
void (*
signal(int s, void (*a)()))()
{
struct sigvec osv;
struct sigvec nsv;
static int mask[NSIG];
static int flags[NSIG];
nsv.sv_handler = a;
nsv.sv_mask = mask[s];
nsv.sv_flags = flags[s];
if (sigvec(s, &nsv, &osv) < 0)
return (SIG_ERR);
if (nsv.sv_mask != osv.sv_mask || nsv.sv_flags != osv.sv_flags) {
mask[s] = nsv.sv_mask = osv.sv_mask;
flags[s] = nsv.sv_flags = osv.sv_flags & ~SV_RESETHAND;
if (sigvec(s, &nsv, (struct sigvec *)0) < 0)
return (SIG_ERR);
}
return (osv.sv_handler);
}
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