OpenSolaris Launch

1 files changed, 163 insertions, 0 deletions

diff --git a/usr/src/cmd/sh/stak.c b/usr/src/cmd/sh/stak.c
new file mode 100644
index 0000000000..6e1f90eb5f
--- /dev/null
+++ b/usr/src/cmd/sh/stak.c
@@ -0,0 +1,163 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 1992 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
+/*	  All Rights Reserved  	*/
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+/*
+ * UNIX shell
+ */
+
+#include	"defs.h"
+
+
+/* ========	storage allocation	======== */
+
+unsigned char *
+getstak(asize)			/* allocate requested stack */
+int	asize;
+{
+	register unsigned char	*oldstak;
+	register int	size;
+
+	size = round(asize, BYTESPERWORD);
+	oldstak = stakbot;
+	staktop = stakbot += size;
+	if (staktop >= brkend)
+		growstak(staktop);
+	return(oldstak);
+}
+
+/*
+ * set up stack for local use
+ * should be followed by `endstak'
+ */
+unsigned char *
+locstak()
+{
+	if (brkend - stakbot < BRKINCR)
+	{
+		if (setbrk(brkincr) == -1)
+			error(nostack);
+		if (brkincr < BRKMAX)
+			brkincr += 256;
+	}
+	return(stakbot);
+}
+
+void
+growstak(newtop)
+unsigned char	*newtop;
+{
+	register unsigned	incr;
+
+	incr = (unsigned)round(newtop - brkend + 1, BYTESPERWORD);
+	if (brkincr > incr)
+		incr = brkincr;
+	if (setbrk(incr) == -1)
+		error(nospace);
+}
+
+unsigned char *
+savstak()
+{
+	assert(staktop == stakbot);
+	return(stakbot);
+}
+
+unsigned char *
+endstak(argp)		/* tidy up after `locstak' */
+register unsigned char	*argp;
+{
+	register unsigned char	*oldstak;
+
+	if (argp >= brkend)
+		growstak(argp);
+	*argp++ = 0;
+	oldstak = stakbot;
+	stakbot = staktop = (unsigned char *)round(argp, BYTESPERWORD);
+	if (staktop >= brkend)
+		growstak(staktop);
+	return(oldstak);
+}
+
+tdystak(x)		/* try to bring stack back to x */
+register unsigned char	*x;
+{
+	while ((unsigned char *)stakbsy > x)
+	{
+		free(stakbsy);
+		stakbsy = stakbsy->word;
+	}
+	staktop = stakbot = max(x, stakbas);
+	rmtemp(x);
+}
+
+stakchk()
+{
+	if ((brkend - stakbas) > BRKINCR + BRKINCR)
+		setbrk(-BRKINCR);
+}
+
+unsigned char *
+cpystak(x)
+unsigned char	*x;
+{
+	return(endstak(movstrstak(x, locstak())));
+}
+
+unsigned char *
+movstrstak(a, b)
+register unsigned char	*a, *b;
+{
+	do
+	{
+		if (b >= brkend)
+			growstak(b);
+	}
+	while (*b++ = *a++);
+	return(--b);
+}
+
+/*
+ * Copy s2 to s1, always copy n bytes.
+ * Return s1
+ */
+unsigned char *
+memcpystak(s1, s2, n)
+register unsigned char *s1, *s2;
+register int n;
+{
+	register unsigned char *os1 = s1;
+
+	while (--n >= 0) {
+		if (s1 >= brkend)
+			growstak(s1);
+		*s1++ = *s2++;
+	}
+	return (os1);
+}