Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 140 insertions, 0 deletions

diff --git a/REORG.TODO/login/openpty.c b/REORG.TODO/login/openpty.c
new file mode 100644
index 0000000000..41ab0483e2
--- /dev/null
+++ b/REORG.TODO/login/openpty.c
@@ -0,0 +1,140 @@
+/* Copyright (C) 1998-2017 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <pty.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+
+/* Return the result of ptsname_r in the buffer pointed to by PTS,
+   which should be of length BUF_LEN.  If it is too long to fit in
+   this buffer, a sufficiently long buffer is allocated using malloc,
+   and returned in PTS.  0 is returned upon success, -1 otherwise.  */
+static int
+pts_name (int fd, char **pts, size_t buf_len)
+{
+  int rv;
+  char *buf = *pts;
+
+  for (;;)
+    {
+      char *new_buf;
+
+      if (buf_len)
+	{
+	  rv = ptsname_r (fd, buf, buf_len);
+
+	  if (rv != 0 || memchr (buf, '\0', buf_len))
+	    /* We either got an error, or we succeeded and the
+	       returned name fit in the buffer.  */
+	    break;
+
+	  /* Try again with a longer buffer.  */
+	  buf_len += buf_len;	/* Double it */
+	}
+      else
+	/* No initial buffer; start out by mallocing one.  */
+	buf_len = 128;		/* First time guess.  */
+
+      if (buf != *pts)
+	/* We've already malloced another buffer at least once.  */
+	new_buf = realloc (buf, buf_len);
+      else
+	new_buf = malloc (buf_len);
+      if (! new_buf)
+	{
+	  rv = -1;
+	  __set_errno (ENOMEM);
+	  break;
+	}
+      buf = new_buf;
+    }
+
+  if (rv == 0)
+    *pts = buf;		/* Return buffer to the user.  */
+  else if (buf != *pts)
+    free (buf);		/* Free what we malloced when returning an error.  */
+
+  return rv;
+}
+
+/* Create pseudo tty master slave pair and set terminal attributes
+   according to TERMP and WINP.  Return handles for both ends in
+   AMASTER and ASLAVE, and return the name of the slave end in NAME.  */
+int
+openpty (int *amaster, int *aslave, char *name,
+	 const struct termios *termp, const struct winsize *winp)
+{
+#ifdef PATH_MAX
+  char _buf[PATH_MAX];
+#else
+  char _buf[512];
+#endif
+  char *buf = _buf;
+  int master, slave;
+
+  master = getpt ();
+  if (master == -1)
+    return -1;
+
+  if (grantpt (master))
+    goto fail;
+
+  if (unlockpt (master))
+    goto fail;
+
+  if (pts_name (master, &buf, sizeof (_buf)))
+    goto fail;
+
+  slave = open (buf, O_RDWR | O_NOCTTY);
+  if (slave == -1)
+    {
+      if (buf != _buf)
+	free (buf);
+
+      goto fail;
+    }
+
+  /* XXX Should we ignore errors here?  */
+  if (termp)
+    tcsetattr (slave, TCSAFLUSH, termp);
+#ifdef TIOCSWINSZ
+  if (winp)
+    ioctl (slave, TIOCSWINSZ, winp);
+#endif
+
+  *amaster = master;
+  *aslave = slave;
+  if (name != NULL)
+    strcpy (name, buf);
+
+  if (buf != _buf)
+    free (buf);
+  return 0;
+
+ fail:
+  close (master);
+  return -1;
+}
+libutil_hidden_def (openpty)