| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <sys/ioctl.h> |
| #include <linux/kd.h> |
| #include "nls.h" |
| #include "getfd.h" |
| |
| static char *conspath[] = { |
| "/proc/self/fd/0", |
| "/dev/tty", |
| "/dev/tty0", |
| "/dev/vc/0", |
| "/dev/systty", |
| "/dev/console", |
| NULL |
| }; |
| |
| /* |
| * getfd.c |
| * |
| * Get an fd for use with kbd/console ioctls. |
| * We try several things because opening /dev/console will fail |
| * if someone else used X (which does a chown on /dev/console). |
| */ |
| |
| static int |
| is_a_console(int fd) { |
| char arg; |
| |
| arg = 0; |
| return (isatty (fd) |
| && ioctl(fd, KDGKBTYPE, &arg) == 0 |
| && ((arg == KB_101) || (arg == KB_84))); |
| } |
| |
| static int |
| open_a_console(const char *fnam) { |
| int fd; |
| |
| /* |
| * For ioctl purposes we only need some fd and permissions |
| * do not matter. But setfont:activatemap() does a write. |
| */ |
| fd = open(fnam, O_RDWR); |
| if (fd < 0) |
| fd = open(fnam, O_WRONLY); |
| if (fd < 0) |
| fd = open(fnam, O_RDONLY); |
| if (fd < 0) |
| return -1; |
| return fd; |
| } |
| |
| int |
| getfd(const char *fnam) { |
| int fd, i; |
| |
| if (fnam) { |
| if ((fd = open_a_console(fnam)) >= 0) { |
| if (is_a_console(fd)) |
| return fd; |
| close(fd); |
| } |
| fprintf(stderr, _("Couldn't open %s\n"), fnam); |
| exit(1); |
| } |
| |
| for (i = 0; conspath[i]; i++) { |
| if ((fd = open_a_console(conspath[i])) >= 0) { |
| if (is_a_console(fd)) |
| return fd; |
| close(fd); |
| } |
| } |
| |
| for (fd = 0; fd < 3; fd++) |
| if (is_a_console(fd)) |
| return fd; |
| |
| fprintf(stderr, |
| _("Couldn't get a file descriptor referring to the console\n")); |
| |
| /* total failure */ |
| exit(1); |
| } |