1 76193d7c 2003-09-30 devnull #include "threadimpl.h"
 2 76193d7c 2003-09-30 devnull 
 3 76193d7c 2003-09-30 devnull #define PIPEMNT	"/mnt/temp"
 4 76193d7c 2003-09-30 devnull 
 5 76193d7c 2003-09-30 devnull void
 6 76193d7c 2003-09-30 devnull procexec(Channel *pidc, char *prog, char *args[])
 7 76193d7c 2003-09-30 devnull {
 8 76193d7c 2003-09-30 devnull 	int n;
 9 76193d7c 2003-09-30 devnull 	Proc *p;
10 76193d7c 2003-09-30 devnull 	Thread *t;
11 76193d7c 2003-09-30 devnull 
12 76193d7c 2003-09-30 devnull 	_threaddebug(DBGEXEC, "procexec %s", prog);
13 76193d7c 2003-09-30 devnull 	/* must be only thread in proc */
14 76193d7c 2003-09-30 devnull 	p = _threadgetproc();
15 76193d7c 2003-09-30 devnull 	t = p->thread;
16 76193d7c 2003-09-30 devnull 	if(p->threads.head != t || p->threads.head->nextt != nil){
17 76193d7c 2003-09-30 devnull 		werrstr("not only thread in proc");
18 76193d7c 2003-09-30 devnull 	Bad:
19 76193d7c 2003-09-30 devnull 		if(pidc)
20 76193d7c 2003-09-30 devnull 			sendul(pidc, ~0);
21 76193d7c 2003-09-30 devnull 		return;
22 76193d7c 2003-09-30 devnull 	}
23 76193d7c 2003-09-30 devnull 
24 76193d7c 2003-09-30 devnull 	/*
25 76193d7c 2003-09-30 devnull 	 * We want procexec to behave like exec; if exec succeeds,
26 76193d7c 2003-09-30 devnull 	 * never return, and if it fails, return with errstr set.
27 76193d7c 2003-09-30 devnull 	 * Unfortunately, the exec happens in another proc since
28 76193d7c 2003-09-30 devnull 	 * we have to wait for the exec'ed process to finish.
29 76193d7c 2003-09-30 devnull 	 * To provide the semantics, we open a pipe with the 
30 76193d7c 2003-09-30 devnull 	 * write end close-on-exec and hand it to the proc that
31 76193d7c 2003-09-30 devnull 	 * is doing the exec.  If the exec succeeds, the pipe will
32 76193d7c 2003-09-30 devnull 	 * close so that our read below fails.  If the exec fails,
33 76193d7c 2003-09-30 devnull 	 * then the proc doing the exec sends the errstr down the
34 76193d7c 2003-09-30 devnull 	 * pipe to us.
35 76193d7c 2003-09-30 devnull 	 */
36 76193d7c 2003-09-30 devnull 	if(bind("#|", PIPEMNT, MREPL) < 0)
37 76193d7c 2003-09-30 devnull 		goto Bad;
38 76193d7c 2003-09-30 devnull 	if((p->exec.fd[0] = open(PIPEMNT "/data", OREAD)) < 0){
39 76193d7c 2003-09-30 devnull 		unmount(nil, PIPEMNT);
40 76193d7c 2003-09-30 devnull 		goto Bad;
41 76193d7c 2003-09-30 devnull 	}
42 76193d7c 2003-09-30 devnull 	if((p->exec.fd[1] = open(PIPEMNT "/data1", OWRITE|OCEXEC)) < 0){
43 76193d7c 2003-09-30 devnull 		close(p->exec.fd[0]);
44 76193d7c 2003-09-30 devnull 		unmount(nil, PIPEMNT);
45 76193d7c 2003-09-30 devnull 		goto Bad;
46 76193d7c 2003-09-30 devnull 	}
47 76193d7c 2003-09-30 devnull 	unmount(nil, PIPEMNT);
48 76193d7c 2003-09-30 devnull 
49 76193d7c 2003-09-30 devnull 	/* exec in parallel via the scheduler */
50 76193d7c 2003-09-30 devnull 	assert(p->needexec==0);
51 76193d7c 2003-09-30 devnull 	p->exec.prog = prog;
52 76193d7c 2003-09-30 devnull 	p->exec.args = args;
53 76193d7c 2003-09-30 devnull 	p->needexec = 1;
54 76193d7c 2003-09-30 devnull 	_sched();
55 76193d7c 2003-09-30 devnull 
56 76193d7c 2003-09-30 devnull 	close(p->exec.fd[1]);
57 76193d7c 2003-09-30 devnull 	if((n = read(p->exec.fd[0], p->exitstr, ERRMAX-1)) > 0){	/* exec failed */
58 76193d7c 2003-09-30 devnull 		p->exitstr[n] = '\0';
59 76193d7c 2003-09-30 devnull 		errstr(p->exitstr, ERRMAX);
60 76193d7c 2003-09-30 devnull 		close(p->exec.fd[0]);
61 76193d7c 2003-09-30 devnull 		goto Bad;
62 76193d7c 2003-09-30 devnull 	}
63 76193d7c 2003-09-30 devnull 	close(p->exec.fd[0]);
64 76193d7c 2003-09-30 devnull 
65 76193d7c 2003-09-30 devnull 	if(pidc)
66 76193d7c 2003-09-30 devnull 		sendul(pidc, t->ret);
67 76193d7c 2003-09-30 devnull 
68 76193d7c 2003-09-30 devnull 	/* wait for exec'ed program, then exit */
69 76193d7c 2003-09-30 devnull 	_schedexecwait();
70 76193d7c 2003-09-30 devnull }
71 76193d7c 2003-09-30 devnull 
72 76193d7c 2003-09-30 devnull void
73 76193d7c 2003-09-30 devnull procexecl(Channel *pidc, char *f, ...)
74 76193d7c 2003-09-30 devnull {
75 76193d7c 2003-09-30 devnull 	procexec(pidc, f, &f+1);
76 76193d7c 2003-09-30 devnull }
77 76193d7c 2003-09-30 devnull