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authorEric Andersen <andersen@codepoet.org>2001-05-08 19:58:20 +0000
committerEric Andersen <andersen@codepoet.org>2001-05-08 19:58:20 +0000
commita3e03be058a9b9a2caf36c5b18f66c0fc3df3bf0 (patch)
tree2ad333bd1e56590e981eba3c54f6057cbf5758bb /libutil/openpty.c
parent6c0899094d50e0d35d699594bfcd9cae4164abe2 (diff)
Add in libutil, based on Cory Visi's variant of Michael Shmulevich's libutil
port. I have reworked the code quite a bit so that the stuff that is supposed to be in libc is in libc, and I added a bunch of missing stuff so the libutil interface matches that of glibc's libutil. The only caveat is that libutil/login.c is currently a stub. -Erik
Diffstat (limited to 'libutil/openpty.c')
-rw-r--r--libutil/openpty.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/libutil/openpty.c b/libutil/openpty.c
new file mode 100644
index 000000000..1c2adbf6a
--- /dev/null
+++ b/libutil/openpty.c
@@ -0,0 +1,142 @@
+/* Copyright (C) 1998, 1999 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 <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>
+
+extern int getpt (void);
+extern int grantpt (int fd);
+extern int ptsname_r (int fd, char *buf, size_t buflen);
+extern int unlockpt (int fd);
+
+/* 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;
+ 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, struct termios *termp,
+ 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);
+ if (winp)
+ ioctl (slave, TIOCSWINSZ, winp);
+
+ *amaster = master;
+ *aslave = slave;
+ if (name != NULL)
+ strcpy (name, buf);
+
+ if (buf != _buf)
+ free (buf);
+ return 0;
+
+ fail:
+ close (master);
+ return -1;
+}