xref: /aosp_15_r20/external/musl/src/misc/openpty.c (revision c9945492fdd68bbe62686c5b452b4dc1be3f8453)
1*c9945492SAndroid Build Coastguard Worker #include <stdlib.h>
2*c9945492SAndroid Build Coastguard Worker #include <fcntl.h>
3*c9945492SAndroid Build Coastguard Worker #include <unistd.h>
4*c9945492SAndroid Build Coastguard Worker #include <pty.h>
5*c9945492SAndroid Build Coastguard Worker #include <stdio.h>
6*c9945492SAndroid Build Coastguard Worker #include <pthread.h>
7*c9945492SAndroid Build Coastguard Worker 
8*c9945492SAndroid Build Coastguard Worker /* Nonstandard, but vastly superior to the standard functions */
9*c9945492SAndroid Build Coastguard Worker 
openpty(int * pm,int * ps,char * name,const struct termios * tio,const struct winsize * ws)10*c9945492SAndroid Build Coastguard Worker int openpty(int *pm, int *ps, char *name, const struct termios *tio, const struct winsize *ws)
11*c9945492SAndroid Build Coastguard Worker {
12*c9945492SAndroid Build Coastguard Worker 	int m, s, n=0, cs;
13*c9945492SAndroid Build Coastguard Worker 	char buf[20];
14*c9945492SAndroid Build Coastguard Worker 
15*c9945492SAndroid Build Coastguard Worker 	m = open("/dev/ptmx", O_RDWR|O_NOCTTY);
16*c9945492SAndroid Build Coastguard Worker 	if (m < 0) return -1;
17*c9945492SAndroid Build Coastguard Worker 
18*c9945492SAndroid Build Coastguard Worker 	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
19*c9945492SAndroid Build Coastguard Worker 
20*c9945492SAndroid Build Coastguard Worker 	if (ioctl(m, TIOCSPTLCK, &n) || ioctl (m, TIOCGPTN, &n))
21*c9945492SAndroid Build Coastguard Worker 		goto fail;
22*c9945492SAndroid Build Coastguard Worker 
23*c9945492SAndroid Build Coastguard Worker 	if (!name) name = buf;
24*c9945492SAndroid Build Coastguard Worker 	snprintf(name, sizeof buf, "/dev/pts/%d", n);
25*c9945492SAndroid Build Coastguard Worker 	if ((s = open(name, O_RDWR|O_NOCTTY)) < 0)
26*c9945492SAndroid Build Coastguard Worker 		goto fail;
27*c9945492SAndroid Build Coastguard Worker 
28*c9945492SAndroid Build Coastguard Worker 	if (tio) tcsetattr(s, TCSANOW, tio);
29*c9945492SAndroid Build Coastguard Worker 	if (ws) ioctl(s, TIOCSWINSZ, ws);
30*c9945492SAndroid Build Coastguard Worker 
31*c9945492SAndroid Build Coastguard Worker 	*pm = m;
32*c9945492SAndroid Build Coastguard Worker 	*ps = s;
33*c9945492SAndroid Build Coastguard Worker 
34*c9945492SAndroid Build Coastguard Worker 	pthread_setcancelstate(cs, 0);
35*c9945492SAndroid Build Coastguard Worker 	return 0;
36*c9945492SAndroid Build Coastguard Worker fail:
37*c9945492SAndroid Build Coastguard Worker 	close(m);
38*c9945492SAndroid Build Coastguard Worker 	pthread_setcancelstate(cs, 0);
39*c9945492SAndroid Build Coastguard Worker 	return -1;
40*c9945492SAndroid Build Coastguard Worker }
41