/*
* get_pty - get a pty master/slave pair and chown the slave side
- * to the uid given. Assumes slave_name points to >= 12 bytes of space.
+ * to the uid given. Assumes slave_name points to >= 16 bytes of space.
*/
int
get_pty(master_fdp, slave_fdp, slave_name, uid)
char *slave_name;
int uid;
{
- int i, mfd, sfd;
- char pty_name[12];
+ int i, mfd, sfd = -1;
+ char pty_name[16];
struct termios tios;
- sfd = -1;
- for (i = 0; i < 64; ++i) {
- slprintf(pty_name, sizeof(pty_name), "/dev/pty%c%x",
- 'p' + i / 16, i % 16);
- mfd = open(pty_name, O_RDWR, 0);
- if (mfd >= 0) {
- pty_name[5] = 't';
- sfd = open(pty_name, O_RDWR | O_NOCTTY, 0);
- if (sfd >= 0)
- break;
- close(mfd);
+#ifdef TIOCGPTN
+ /*
+ * Try the unix98 way first.
+ */
+ mfd = open("/dev/ptmx", O_RDWR);
+ if (mfd >= 0) {
+ int ptn;
+ if (ioctl(mfd, TIOCGPTN, &ptn) >= 0) {
+ slprintf(pty_name, sizeof(pty_name), "/dev/pts/%d", ptn);
+ chmod(pty_name, S_IRUSR | S_IWUSR);
+#ifdef TIOCSPTLCK
+ ptn = 0;
+ if (ioctl(mfd, TIOCSPTLCK, &ptn) < 0)
+ warn("Couldn't unlock pty slave %s: %m", pty_name);
+#endif
+ if ((sfd = open(pty_name, O_RDWR)) < 0)
+ warn("Couldn't open pty slave %s: %m", pty_name);
}
}
+#endif /* TIOCGPTN */
+
+ if (sfd < 0) {
+ /* the old way - scan through the pty name space */
+ for (i = 0; i < 64; ++i) {
+ slprintf(pty_name, sizeof(pty_name), "/dev/pty%c%x",
+ 'p' + i / 16, i % 16);
+ mfd = open(pty_name, O_RDWR, 0);
+ if (mfd >= 0) {
+ pty_name[5] = 't';
+ sfd = open(pty_name, O_RDWR | O_NOCTTY, 0);
+ if (sfd >= 0) {
+ fchown(sfd, uid, -1);
+ fchmod(sfd, S_IRUSR | S_IWUSR);
+ break;
+ }
+ close(mfd);
+ }
+ }
+ }
+
if (sfd < 0)
return 0;
- strlcpy(slave_name, pty_name, 12);
+ strlcpy(slave_name, pty_name, 16);
*master_fdp = mfd;
*slave_fdp = sfd;
- fchown(sfd, uid, -1);
- fchmod(sfd, S_IRUSR | S_IWUSR);
if (tcgetattr(sfd, &tios) == 0) {
tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB);
tios.c_cflag |= CS8 | CREAD;