BSD 4.4 Lite Kernel Sources

1 files changed, 147 insertions, 0 deletions

diff --git a/sys/kern/tty_tty.c b/sys/kern/tty_tty.c
new file mode 100644
index 0000000..964fc6f
--- /dev/null
+++ b/sys/kern/tty_tty.c
@@ -0,0 +1,147 @@
+/*-
+ * Copyright (c) 1982, 1986, 1991, 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.
+ *
+ *	@(#)tty_tty.c	8.2 (Berkeley) 9/23/93
+ */
+
+/*
+ * Indirect driver for controlling tty.
+ */
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/ioctl.h>
+#include <sys/proc.h>
+#include <sys/tty.h>
+#include <sys/vnode.h>
+#include <sys/file.h>
+
+#define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
+
+/*ARGSUSED*/
+cttyopen(dev, flag, mode, p)
+	dev_t dev;
+	int flag, mode;
+	struct proc *p;
+{
+	struct vnode *ttyvp = cttyvp(p);
+	int error;
+
+	if (ttyvp == NULL)
+		return (ENXIO);
+	VOP_LOCK(ttyvp);
+#ifdef PARANOID
+	/*
+	 * Since group is tty and mode is 620 on most terminal lines
+	 * and since sessions protect terminals from processes outside
+	 * your session, this check is probably no longer necessary.
+	 * Since it inhibits setuid root programs that later switch 
+	 * to another user from accessing /dev/tty, we have decided
+	 * to delete this test. (mckusick 5/93)
+	 */
+	error = VOP_ACCESS(ttyvp,
+	  (flag&FREAD ? VREAD : 0) | (flag&FWRITE ? VWRITE : 0), p->p_ucred, p);
+	if (!error)
+#endif /* PARANOID */
+		error = VOP_OPEN(ttyvp, flag, NOCRED, p);
+	VOP_UNLOCK(ttyvp);
+	return (error);
+}
+
+/*ARGSUSED*/
+cttyread(dev, uio, flag)
+	dev_t dev;
+	struct uio *uio;
+	int flag;
+{
+	register struct vnode *ttyvp = cttyvp(uio->uio_procp);
+	int error;
+
+	if (ttyvp == NULL)
+		return (EIO);
+	VOP_LOCK(ttyvp);
+	error = VOP_READ(ttyvp, uio, flag, NOCRED);
+	VOP_UNLOCK(ttyvp);
+	return (error);
+}
+
+/*ARGSUSED*/
+cttywrite(dev, uio, flag)
+	dev_t dev;
+	struct uio *uio;
+	int flag;
+{
+	register struct vnode *ttyvp = cttyvp(uio->uio_procp);
+	int error;
+
+	if (ttyvp == NULL)
+		return (EIO);
+	VOP_LOCK(ttyvp);
+	error = VOP_WRITE(ttyvp, uio, flag, NOCRED);
+	VOP_UNLOCK(ttyvp);
+	return (error);
+}
+
+/*ARGSUSED*/
+cttyioctl(dev, cmd, addr, flag, p)
+	dev_t dev;
+	int cmd;
+	caddr_t addr;
+	int flag;
+	struct proc *p;
+{
+	struct vnode *ttyvp = cttyvp(p);
+
+	if (ttyvp == NULL)
+		return (EIO);
+	if (cmd == TIOCNOTTY) {
+		if (!SESS_LEADER(p)) {
+			p->p_flag &= ~P_CONTROLT;
+			return (0);
+		} else
+			return (EINVAL);
+	}
+	return (VOP_IOCTL(ttyvp, cmd, addr, flag, NOCRED, p));
+}
+
+/*ARGSUSED*/
+cttyselect(dev, flag, p)
+	dev_t dev;
+	int flag;
+	struct proc *p;
+{
+	struct vnode *ttyvp = cttyvp(p);
+
+	if (ttyvp == NULL)
+		return (1);	/* try operation to get EOF/failure */
+	return (VOP_SELECT(ttyvp, flag, FREAD|FWRITE, NOCRED, p));
+}