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#include "threadimpl.h"
#undef pipe
#undef wait
static int sigpid;
static int threadpassfd;
static void
child(void)
{
int status;
if(wait(&status) == sigpid)
if(WIFEXITED(status))
_exit(WEXITSTATUS(status));
_exit(97);
}
static void
sigpass(int sig)
{
if(sig == SIGCHLD)
child();
else
kill(sigpid, sig);
}
void
_threadsetupdaemonize(void)
{
int i, n, pid;
int p[2];
char buf[20];
sigpid = 1;
threadlinklibrary();
if(pipe(p) < 0)
sysfatal("passer pipe: %r");
/* hide these somewhere they won't cause harm */
if(dup(p[0], 98) < 0 || dup(p[1], 99) < 0)
sysfatal("passer pipe dup: %r");
close(p[0]);
close(p[1]);
p[0] = 98;
p[1] = 99;
/* close on exec */
if(fcntl(p[0], F_SETFD, 1) < 0 || fcntl(p[1], F_SETFD, 1) < 0)
sysfatal("passer pipe pipe fcntl: %r");
switch(pid = fork()){
case -1:
sysfatal("passer fork: %r");
default:
close(p[1]);
break;
case 0:
rfork(RFNOTEG);
close(p[0]);
threadpassfd = p[1];
return;
}
sigpid = pid;
for(i=0; i<NSIG; i++){
struct sigaction sa;
memset(&sa, 0, sizeof sa);
sa.sa_handler = sigpass;
sa.sa_flags |= SA_RESTART;
sigaction(i, &sa, nil);
}
for(;;){
n = read(p[0], buf, sizeof buf-1);
if(n == 0) /* program exited */
child();
if(n > 0)
break;
print("passer read: %r\n");
}
buf[n] = 0;
_exit(atoi(buf));
}
void
threaddaemonize(void)
{
write(threadpassfd, "0", 1);
close(threadpassfd);
threadpassfd = -1;
}
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