diff options
Diffstat (limited to 'sysdeps/posix/ttyname_r.c')
-rw-r--r-- | sysdeps/posix/ttyname_r.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/sysdeps/posix/ttyname_r.c b/sysdeps/posix/ttyname_r.c new file mode 100644 index 0000000..e225da2 --- /dev/null +++ b/sysdeps/posix/ttyname_r.c @@ -0,0 +1,91 @@ +/* Copyright (C) 1991, 1992, 1993, 1995 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <errno.h> +#include <limits.h> +#include <stddef.h> +#include <dirent.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <string.h> +#include <stdlib.h> + +#ifndef MIN +# define MIN(a, b) ((a) < (b) ? (a) : (b)) +#endif + +/* Store at most BUFLEN character of the pathname of the terminal FD is + open on in BUF. Return 0 on success, -1 otherwise. */ +int +ttyname_r (fd, buf, buflen) + int fd; + char *buf; + int buflen; +{ + static const char dev[] = "/dev"; + struct stat st; + dev_t mydev; + ino_t myino; + DIR *dirstream; + struct dirent *d; + int save = errno; + + /* Test for the absolute minimal size. This makes life easier inside + the loop. */ + if (buflen < sizeof (dev) + 2) + { + errno = EINVAL; + return -1; + } + + if (fstat (fd, &st) < 0) + return -1; + mydev = st.st_dev; + myino = st.st_ino; + + dirstream = opendir (dev); + if (dirstream == NULL) + return -1; + + /* Prepare the result buffer. */ + memcpy (buf, dev, sizeof (dev)); + buf[sizeof (dev)] = '/'; + buflen -= sizeof (dev) + 1; + + while ((d = readdir (dirstream)) != NULL) + if (d->d_fileno == myino) + { + char *cp; + + cp = stpncpy (&buf[sizeof (dev) + 1], d->d_name, + MIN (d->d_namlen + 1, buflen)); + cp[0] = '\0'; + + if (stat (buf, &st) == 0 && st.st_dev == mydev) + { + (void) closedir (dirstream); + errno = save; + return 0; + } + } + + (void) closedir (dirstream); + errno = save; + return -1; +} |