1 a0a331aa 2005-01-06 devnull #include <u.h>
  2 a0a331aa 2005-01-06 devnull #include <sys/time.h>
  3 a0a331aa 2005-01-06 devnull #include <sys/resource.h>
  4 ddb664da 2004-12-28 devnull #include "threadimpl.h"
  5 ddb664da 2004-12-28 devnull 
  6 230ead2f 2005-01-04 devnull #undef waitpid
  7 ddb664da 2004-12-28 devnull #undef pipe
  8 ddb664da 2004-12-28 devnull #undef wait
  9 ddb664da 2004-12-28 devnull 
 10 ddb664da 2004-12-28 devnull static int sigpid;
 11 ddb664da 2004-12-28 devnull static int threadpassfd;
 12 ddb664da 2004-12-28 devnull 
 13 ddb664da 2004-12-28 devnull static void
 14 ddb664da 2004-12-28 devnull child(void)
 15 ddb664da 2004-12-28 devnull {
 16 1d2533d0 2004-12-28 devnull 	int status, pid;
 17 a0a331aa 2005-01-06 devnull 	struct rlimit rl;
 18 230ead2f 2005-01-04 devnull 
 19 230ead2f 2005-01-04 devnull 	notedisable("sys: child");
 20 230ead2f 2005-01-04 devnull 	pid = waitpid(sigpid, &status, 0);
 21 230ead2f 2005-01-04 devnull 	if(pid < 0){
 22 230ead2f 2005-01-04 devnull 		fprint(2, "%s: wait: %r\n", argv0);
 23 230ead2f 2005-01-04 devnull 		_exit(97);
 24 230ead2f 2005-01-04 devnull 	}
 25 230ead2f 2005-01-04 devnull 	if(WIFEXITED(status))
 26 1d2533d0 2004-12-28 devnull 		 _exit(WEXITSTATUS(status));
 27 230ead2f 2005-01-04 devnull 	if(WIFSIGNALED(status)){
 28 a0a331aa 2005-01-06 devnull 		/*
 29 a0a331aa 2005-01-06 devnull 		 * Make sure we don't scribble over the nice
 30 a0a331aa 2005-01-06 devnull 		 * core file that our child just wrote out.
 31 a0a331aa 2005-01-06 devnull 		 */
 32 a0a331aa 2005-01-06 devnull 		rl.rlim_cur = 0;
 33 a0a331aa 2005-01-06 devnull 		rl.rlim_max = 0;
 34 a0a331aa 2005-01-06 devnull 		setrlimit(RLIMIT_CORE, &rl);
 35 a0a331aa 2005-01-06 devnull 
 36 230ead2f 2005-01-04 devnull 		signal(WTERMSIG(status), SIG_DFL);
 37 230ead2f 2005-01-04 devnull 		raise(WTERMSIG(status));
 38 230ead2f 2005-01-04 devnull 		_exit(98);	/* not reached */
 39 230ead2f 2005-01-04 devnull 	}
 40 230ead2f 2005-01-04 devnull 	fprint(2, "%s: wait pid %d status 0x%ux\n", pid, status);
 41 230ead2f 2005-01-04 devnull 	_exit(99);
 42 ddb664da 2004-12-28 devnull }
 43 ddb664da 2004-12-28 devnull 
 44 ddb664da 2004-12-28 devnull static void
 45 ddb664da 2004-12-28 devnull sigpass(int sig)
 46 ddb664da 2004-12-28 devnull {
 47 ddb664da 2004-12-28 devnull 	if(sig == SIGCHLD)
 48 ddb664da 2004-12-28 devnull 		child();
 49 ddb664da 2004-12-28 devnull 	else
 50 ddb664da 2004-12-28 devnull 		kill(sigpid, sig);
 51 ddb664da 2004-12-28 devnull }
 52 ddb664da 2004-12-28 devnull 
 53 ddb664da 2004-12-28 devnull void
 54 ddb664da 2004-12-28 devnull _threadsetupdaemonize(void)
 55 ddb664da 2004-12-28 devnull {
 56 ddb664da 2004-12-28 devnull 	int i, n, pid;
 57 ddb664da 2004-12-28 devnull 	int p[2];
 58 ddb664da 2004-12-28 devnull 	char buf[20];
 59 ddb664da 2004-12-28 devnull 
 60 ddb664da 2004-12-28 devnull 	sigpid = 1;
 61 ddb664da 2004-12-28 devnull 
 62 ddb664da 2004-12-28 devnull 	threadlinklibrary();
 63 ddb664da 2004-12-28 devnull 
 64 ddb664da 2004-12-28 devnull 	if(pipe(p) < 0)
 65 ddb664da 2004-12-28 devnull 		sysfatal("passer pipe: %r");
 66 ddb664da 2004-12-28 devnull 
 67 ddb664da 2004-12-28 devnull 	/* hide these somewhere they won't cause harm */
 68 ddb664da 2004-12-28 devnull 	if(dup(p[0], 98) < 0 || dup(p[1], 99) < 0)
 69 ddb664da 2004-12-28 devnull 		sysfatal("passer pipe dup: %r");
 70 ddb664da 2004-12-28 devnull 	close(p[0]);
 71 ddb664da 2004-12-28 devnull 	close(p[1]);
 72 ddb664da 2004-12-28 devnull 	p[0] = 98;
 73 ddb664da 2004-12-28 devnull 	p[1] = 99;
 74 ddb664da 2004-12-28 devnull 
 75 ddb664da 2004-12-28 devnull 	/* close on exec */
 76 ddb664da 2004-12-28 devnull 	if(fcntl(p[0], F_SETFD, 1) < 0 || fcntl(p[1], F_SETFD, 1) < 0)
 77 ddb664da 2004-12-28 devnull 		sysfatal("passer pipe pipe fcntl: %r");
 78 ddb664da 2004-12-28 devnull 
 79 230ead2f 2005-01-04 devnull 	noteenable("sys: child");
 80 1d2533d0 2004-12-28 devnull 	signal(SIGCHLD, sigpass);
 81 ddb664da 2004-12-28 devnull 	switch(pid = fork()){
 82 ddb664da 2004-12-28 devnull 	case -1:
 83 ddb664da 2004-12-28 devnull 		sysfatal("passer fork: %r");
 84 ddb664da 2004-12-28 devnull 	default:
 85 ddb664da 2004-12-28 devnull 		close(p[1]);
 86 ddb664da 2004-12-28 devnull 		break;
 87 ddb664da 2004-12-28 devnull 	case 0:
 88 230ead2f 2005-01-04 devnull 		for(i=0; i<100; i++) sched_yield();
 89 230ead2f 2005-01-04 devnull 		notedisable("sys: child");
 90 1d2533d0 2004-12-28 devnull 		signal(SIGCHLD, SIG_DFL);
 91 ddb664da 2004-12-28 devnull 		rfork(RFNOTEG);
 92 ddb664da 2004-12-28 devnull 		close(p[0]);
 93 ddb664da 2004-12-28 devnull 		threadpassfd = p[1];
 94 ddb664da 2004-12-28 devnull 		return;
 95 ddb664da 2004-12-28 devnull 	}
 96 ddb664da 2004-12-28 devnull 
 97 ddb664da 2004-12-28 devnull 	sigpid = pid;
 98 ddb664da 2004-12-28 devnull 	for(i=0; i<NSIG; i++){
 99 ddb664da 2004-12-28 devnull 		struct sigaction sa;
100 ddb664da 2004-12-28 devnull 
101 ddb664da 2004-12-28 devnull 		memset(&sa, 0, sizeof sa);
102 ddb664da 2004-12-28 devnull 		sa.sa_handler = sigpass;
103 ddb664da 2004-12-28 devnull 		sa.sa_flags |= SA_RESTART;
104 ddb664da 2004-12-28 devnull 		sigaction(i, &sa, nil);
105 ddb664da 2004-12-28 devnull 	}
106 ddb664da 2004-12-28 devnull 
107 ddb664da 2004-12-28 devnull 	for(;;){
108 ddb664da 2004-12-28 devnull 		n = read(p[0], buf, sizeof buf-1);
109 230ead2f 2005-01-04 devnull 		if(n == 0){	/* program exited */
110 ddb664da 2004-12-28 devnull 			child();
111 230ead2f 2005-01-04 devnull 		}
112 ddb664da 2004-12-28 devnull 		if(n > 0)
113 ddb664da 2004-12-28 devnull 			break;
114 d54ead7f 2004-12-28 devnull 		print("passer read: %r\n");
115 ddb664da 2004-12-28 devnull 	}
116 ddb664da 2004-12-28 devnull 	buf[n] = 0;
117 ddb664da 2004-12-28 devnull 	_exit(atoi(buf));
118 ddb664da 2004-12-28 devnull }
119 ddb664da 2004-12-28 devnull 
120 ddb664da 2004-12-28 devnull void
121 230ead2f 2005-01-04 devnull _threaddaemonize(void)
122 ddb664da 2004-12-28 devnull {
123 1d2533d0 2004-12-28 devnull 	if(threadpassfd >= 0){
124 1d2533d0 2004-12-28 devnull 		write(threadpassfd, "0", 1);
125 1d2533d0 2004-12-28 devnull 		close(threadpassfd);
126 1d2533d0 2004-12-28 devnull 		threadpassfd = -1;
127 1d2533d0 2004-12-28 devnull 	}
128 ddb664da 2004-12-28 devnull }