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#include "lib.h"
#include "sys9.h"
#include <signal.h>
#include <errno.h>
#include <string.h>
#include <setjmp.h>
extern sigset_t _psigblocked;
static struct {
char *msg; /* just check prefix */
int num;
} sigtab[] = {
{"hangup", SIGHUP},
{"interrupt", SIGINT},
{"quit", SIGQUIT},
{"alarm", SIGALRM},
{"sys: trap: illegal instruction", SIGILL},
{"sys: trap: reserved instruction", SIGILL},
{"sys: trap: reserved", SIGILL},
{"sys: trap: arithmetic overflow", SIGFPE},
{"abort", SIGABRT},
{"sys: fp:", SIGFPE},
{"exit", SIGKILL},
{"die", SIGKILL},
{"kill", SIGKILL},
{"sys: trap: bus error", SIGSEGV},
{"sys: trap: address error", SIGSEGV},
{"sys: trap: TLB", SIGSEGV},
{"sys: write on closed pipe", SIGPIPE},
{"alarm", SIGALRM},
{"term", SIGTERM},
{"usr1", SIGUSR1},
{"usr2", SIGUSR2},
};
#define NSIGTAB ((sizeof sigtab)/(sizeof (sigtab[0])))
void (*_sighdlr[MAXSIG+1])(int, char*, Ureg*); /* 0 initialized: SIG_DFL */
void
(*signal(int sig, void (*func)(int, char*, Ureg*)))(int, char*, Ureg*)
{
void(*oldf)(int, char*, Ureg*);
if(sig <= 0 || sig > MAXSIG){
errno = EINVAL;
return SIG_ERR;
}
oldf = _sighdlr[sig];
if(sig == SIGKILL)
return oldf; /* can't catch or ignore SIGKILL */
_sighdlr[sig] = func;
return oldf;
}
/* BAD CODE - see /sys/src/ape/lib/ap/$objtype/setjmp.s for real code
int
sigsetjmp(sigjmp_buf buf, int savemask)
{
int r;
buf[0] = savemask;
buf[1] = _psigblocked;
return setjmp(&buf[2]);
}
*/
/*
* BUG: improper handling of process signal mask
*/
int
sigaction(int sig, struct sigaction *act, struct sigaction *oact)
{
if(sig <= 0 || sig > MAXSIG || sig == SIGKILL){
errno = EINVAL;
return -1;
}
if(oact){
oact->sa_handler = _sighdlr[sig];
oact->sa_mask = _psigblocked;
oact->sa_flags = 0;
}
if(act){
_sighdlr[sig] = act->sa_handler;
}
return 0;
}
/* this is registered in _envsetup */
int
_notehandler(Ureg *u, char *msg)
{
int i;
void(*f)(int, char*, Ureg*);
extern void _doatexits(void); /* in stdio/exit.c */
if(_finishing)
_finish(0, 0);
for(i = 0; i<NSIGTAB; i++){
if(strncmp(msg, sigtab[i].msg, strlen(sigtab[i].msg)) == 0){
f = _sighdlr[sigtab[i].num];
if(f == SIG_DFL || f == SIG_ERR)
break;
if(f != SIG_IGN) {
_notetramp(sigtab[i].num, f, u);
/* notetramp is machine-dependent; doesn't return to here */
}
_NOTED(0); /* NCONT */
return;
}
}
_doatexits();
_NOTED(1); /* NDFLT */
}
int
_stringsig(char *nam)
{
int i;
for(i = 0; i<NSIGTAB; i++)
if(strncmp(nam, sigtab[i].msg, strlen(sigtab[i].msg)) == 0)
return sigtab[i].num;
return 0;
}
char *
_sigstring(int sig)
{
int i;
for(i=0; i<NSIGTAB; i++)
if(sigtab[i].num == sig)
return sigtab[i].msg;
return "unknown signal";
}
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