busybox/libbb/getpty.c
Denis Vlasenko defc1ea340 *: introduce and use FAST_FUNC: regparm on i386, otherwise no-on
text    data     bss     dec     hex filename
 808035     611    6868  815514   c719a busybox_old
 804472     611    6868  811951   c63af busybox_unstripped
2008-06-27 02:52:20 +00:00

61 lines
1.1 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini getpty implementation for busybox
* Bjorn Wesen, Axis Communications AB (bjornw@axis.com)
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#define DEBUG 0
int FAST_FUNC xgetpty(char *line)
{
int p;
#if ENABLE_FEATURE_DEVPTS
p = open("/dev/ptmx", O_RDWR);
if (p > 0) {
const char *name;
grantpt(p);
unlockpt(p);
name = ptsname(p);
if (!name) {
bb_perror_msg("ptsname error (is /dev/pts mounted?)");
goto fail;
}
safe_strncpy(line, name, GETPTY_BUFSIZE);
return p;
}
#else
struct stat stb;
int i;
int j;
strcpy(line, "/dev/ptyXX");
for (i = 0; i < 16; i++) {
line[8] = "pqrstuvwxyzabcde"[i];
line[9] = '0';
if (stat(line, &stb) < 0) {
continue;
}
for (j = 0; j < 16; j++) {
line[9] = j < 10 ? j + '0' : j - 10 + 'a';
if (DEBUG)
fprintf(stderr, "Trying to open device: %s\n", line);
p = open(line, O_RDWR | O_NOCTTY);
if (p >= 0) {
line[5] = 't';
return p;
}
}
}
#endif /* FEATURE_DEVPTS */
USE_FEATURE_DEVPTS( fail:)
bb_error_msg_and_die("open pty");
return -1; /* never get here */
}