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Diffstat (limited to 'sysdeps/posix/ttyname_r.c')
-rw-r--r--sysdeps/posix/ttyname_r.c91
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 0000000000..e225da2be2
--- /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;
+}