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-rw-r--r--sysdeps/unix/sysv/linux/ptsname.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/ptsname.c b/sysdeps/unix/sysv/linux/ptsname.c
new file mode 100644
index 0000000000..04feadd436
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/ptsname.c
@@ -0,0 +1,108 @@
+/* Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <termios.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "pty-internal.h"
+
+#include <stdio-common/_itoa.h>
+#include <sys/sysmacros.h>
+
+/* Given the file descriptor of a master pty, return the pathname
+   of the associated slave. */
+
+static char namebuf[PTYNAMELEN];
+extern const char __ptyname1[], __ptyname2[]; /* defined in getpt.c */
+
+char *
+ptsname (fd)
+     int fd;
+{
+  return __ptsname_r (fd, namebuf, PTYNAMELEN);
+}
+
+char *
+__ptsname_r (fd, buf, len)
+     int fd;
+     char *buf;
+     unsigned int len;
+{
+  char nbuf[PTYNAMELEN], idbuf[6];
+  int ptyno;
+  struct stat st;
+
+#ifdef TIOCGPTN
+  static int tiocgptn_works = 1;
+  if (tiocgptn_works)
+    {
+      if (!ioctl (fd, TIOCGPTN, &ptyno))
+	goto gotit;
+      else
+	{
+	  if(errno != EINVAL)
+	    return 0;
+	  else
+	    tiocgptn_works = 0;
+	}
+    }
+#endif
+  /* /dev/ptmx will make it into the kernel before 32 bit dev_t, so
+     this should be safe.  */
+  if (fstat (fd, &st))
+    return 0;
+
+  ptyno = minor (st.st_rdev);
+
+#ifdef TIOCGPTN
+gotit:
+#endif
+  /* Two different possible naming schemes for pty slaves:
+     the SVr4 way.  */
+
+  idbuf[5] = '\0';
+  stpcpy (stpcpy (nbuf, "/dev/pts/"),
+	  _itoa_word (ptyno, &idbuf[4], 10, 0));
+  if (!stat (nbuf, &st))
+    {
+      strncpy (buf, nbuf, len);
+      return buf;
+    }
+  else
+    if (errno != ENOENT)
+      return NULL;
+
+  /* ...and the BSD way.  */
+  nbuf[7]  = 'y';
+  nbuf[8]  = __ptyname1[ptyno / 16];
+  nbuf[9]  = __ptyname2[ptyno % 16];
+  nbuf[10] = '\0';
+
+  if (stat (nbuf, &st))
+    return NULL;
+
+  strncpy (buf, nbuf, len);
+  return buf;
+}
+weak_alias (__ptsname_r, ptsname_r)