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#include <u.h>
#include <signal.h>
#define NOPLAN9DEFINES
#include <libc.h>
extern char *_p9sigstr(int, char*);
static struct {
int sig;
int restart;
} sigs[] = {
SIGHUP, 0,
SIGINT, 0,
SIGQUIT, 0,
SIGILL, 0,
SIGTRAP, 0,
/* SIGABRT, */
#ifdef SIGEMT
SIGEMT, 0,
#endif
SIGFPE, 0,
SIGBUS, 0,
/* SIGSEGV, */
SIGCHLD, 1,
SIGSYS, 0,
SIGPIPE, 0,
SIGALRM, 0,
SIGTERM, 0,
SIGTSTP, 1,
SIGTTIN, 1,
SIGTTOU, 1,
SIGXCPU, 0,
SIGXFSZ, 0,
SIGVTALRM, 0,
SIGUSR1, 0,
SIGUSR2, 0,
SIGWINCH, 1,
#ifdef SIGINFO
SIGINFO, 0,
#endif
};
typedef struct Jmp Jmp;
struct Jmp
{
p9jmp_buf b;
};
static Jmp onejmp;
static Jmp*
getonejmp(void)
{
return &onejmp;
}
Jmp *(*_notejmpbuf)(void) = getonejmp;
static void (*notifyf)(void*, char*);
static void
notifysigf(int sig)
{
int v;
char tmp[64];
Jmp *j;
j = (*_notejmpbuf)();
v = p9setjmp(j->b);
if(v == 0 && notifyf)
(*notifyf)(nil, _p9sigstr(sig, tmp));
else if(v == 2){
if(0)print("HANDLED %d\n", sig);
return;
}
if(0)print("DEFAULT %d\n", sig);
signal(sig, SIG_DFL);
raise(sig);
}
int
noted(int v)
{
p9longjmp((*_notejmpbuf)()->b, v==NCONT ? 2 : 1);
abort();
return 0;
}
int
notify(void (*f)(void*, char*))
{
int i;
struct sigaction sa, osa;
memset(&sa, 0, sizeof sa);
if(f == 0)
sa.sa_handler = SIG_DFL;
else{
notifyf = f;
sa.sa_handler = notifysigf;
}
for(i=0; i<nelem(sigs); i++){
/*
* If someone has already installed a handler,
* It's probably some ld preload nonsense,
* like pct (a SIGVTALRM-based profiler).
* Leave it alone.
*/
sigaction(sigs[i].sig, nil, &osa);
if(osa.sa_handler != SIG_DFL)
continue;
/*
* We assume that one jump buffer per thread
* is okay, which means that we can't deal with
* signal handlers called during signal handlers.
*/
sigfillset(&sa.sa_mask);
if(sigs[i].restart)
sa.sa_flags |= SA_RESTART;
else
sa.sa_flags &= ~SA_RESTART;
sigaction(sigs[i].sig, &sa, nil);
}
return 0;
}
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