1 files changed, 127 insertions, 0 deletions

diff --git a/lib/libutil/pty.c b/lib/libutil/pty.c
new file mode 100644
index 000000000000..1644aee39bb0
--- /dev/null
+++ b/lib/libutil/pty.c
@@ -0,0 +1,127 @@
+/*-
+ * Copyright (c) 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)pty.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <grp.h>
+
+openpty(amaster, aslave, name, termp, winp)
+	int *amaster, *aslave;
+	char *name;
+	struct termios *termp;
+	struct winsize *winp;
+{
+	static char line[] = "/dev/ptyXX";
+	register const char *cp1, *cp2;
+	register int master, slave, ttygid;
+	struct group *gr;
+
+	if ((gr = getgrnam("tty")) != NULL)
+		ttygid = gr->gr_gid;
+	else
+		ttygid = -1;
+
+	for (cp1 = "pqrs"; *cp1; cp1++) {
+		line[8] = *cp1;
+		for (cp2 = "0123456789abcdef"; *cp2; cp2++) {
+			line[9] = *cp2;
+			if ((master = open(line, O_RDWR, 0)) == -1) {
+				if (errno == ENOENT)
+					return (-1);	/* out of ptys */
+			} else {
+				line[5] = 't';
+				(void) chown(line, getuid(), ttygid);
+				(void) chmod(line, S_IRUSR|S_IWUSR|S_IWGRP);
+				(void) revoke(line);
+				if ((slave = open(line, O_RDWR, 0)) != -1) {
+					*amaster = master;
+					*aslave = slave;
+					if (name)
+						strcpy(name, line);
+					if (termp)
+						(void) tcsetattr(slave, 
+							TCSAFLUSH, termp);
+					if (winp)
+						(void) ioctl(slave, TIOCSWINSZ, 
+							(char *)winp);
+					return (0);
+				}
+				(void) close(master);
+				line[5] = 'p';
+			}
+		}
+	}
+	errno = ENOENT;	/* out of ptys */
+	return (-1);
+}
+
+forkpty(amaster, name, termp, winp)
+	int *amaster;
+	char *name;
+	struct termios *termp;
+	struct winsize *winp;
+{
+	int master, slave, pid;
+
+	if (openpty(&master, &slave, name, termp, winp) == -1)
+		return (-1);
+	switch (pid = fork()) {
+	case -1:
+		return (-1);
+	case 0:
+		/* 
+		 * child
+		 */
+		(void) close(master);
+		login_tty(slave);
+		return (0);
+	}
+	/*
+	 * parent
+	 */
+	*amaster = master;
+	(void) close(slave);
+	return (pid);
+}