1 files changed, 136 insertions, 0 deletions
diff --git a/bin/sh/mystring.c b/bin/sh/mystring.c
new file mode 100644
index 0000000..1b9eeea
--- /dev/null
+++ b/bin/sh/mystring.c
@@ -0,0 +1,136 @@
+/*-
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * 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.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)mystring.c	8.1 (Berkeley) 5/31/93";
+#endif /* not lint */
+
+/*
+ * String functions.
+ *
+ *	equal(s1, s2)		Return true if strings are equal.
+ *	scopy(from, to)		Copy a string.
+ *	scopyn(from, to, n)	Like scopy, but checks for overflow.
+ *	number(s)		Convert a string of digits to an integer.
+ *	is_number(s)		Return true if s is a string of digits.
+ */
+
+#include "shell.h"
+#include "syntax.h"
+#include "error.h"
+#include "mystring.h"
+
+
+char nullstr[1];		/* zero length string */
+
+/*
+ * equal - #defined in mystring.h
+ */
+
+/*
+ * scopy - #defined in mystring.h
+ */
+
+
+/*
+ * scopyn - copy a string from "from" to "to", truncating the string
+ *		if necessary.  "To" is always nul terminated, even if
+ *		truncation is performed.  "Size" is the size of "to".
+ */
+
+void
+scopyn(from, to, size)
+	register char const *from;
+	register char *to;
+	register int size;
+	{
+
+	while (--size > 0) {
+		if ((*to++ = *from++) == '\0')
+			return;
+	}
+	*to = '\0';
+}
+
+
+/*
+ * prefix -- see if pfx is a prefix of string.
+ */
+
+int
+prefix(pfx, string)
+	register char const *pfx;
+	register char const *string;
+	{
+	while (*pfx) {
+		if (*pfx++ != *string++)
+			return 0;
+	}
+	return 1;
+}
+
+
+/*
+ * Convert a string of digits to an integer, printing an error message on
+ * failure.
+ */
+
+int
+number(s)
+	const char *s;
+	{
+
+	if (! is_number(s))
+		error2("Illegal number", (char *)s);
+	return atoi(s);
+}
+
+
+
+/*
+ * Check for a valid number.  This should be elsewhere.
+ */
+
+int
+is_number(p)
+	register const char *p;
+	{
+	do {
+		if (! is_digit(*p))
+			return 0;
+	} while (*++p != '\0');
+	return 1;
+}