Add strtok_r() for reentrant (thread-aware) programs

lib/libc/string/Makefile.inc

@@ -1,11 +1,11 @@
 #	from: @(#)Makefile.inc	5.6 (Berkeley) 3/5/91
-#	$Id: Makefile.inc,v 1.36 1996/09/24 09:14:18 matthias Exp $
+#	$Id: Makefile.inc,v 1.37 1996/11/12 02:03:13 jtc Exp $
 
 # string sources
 .PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/string ${.CURDIR}/string
 
 SRCS+=	bm.c strcasecmp.c strcoll.c strdup.c strerror.c \
-	strftime.c strmode.c strsignal.c strtok.c strxfrm.c \
+	strftime.c strmode.c strsignal.c strtok.c strtok_r.c strxfrm.c \
 	__strerror.c __strsignal.c
 
 # machine-dependent net sources

lib/libc/string/strtok.3

@@ -34,7 +34,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     from: @(#)strtok.3	5.8 (Berkeley) 6/29/91
-.\"	$Id: strtok.3,v 1.3 1995/05/13 07:41:35 jtc Exp $
+.\"	$Id: strtok.3,v 1.4 1996/11/12 02:03:14 jtc Exp $
 .\"
 .Dd June 29, 1991
 .Dt STRTOK 3
@@ -47,6 +47,8 @@
 .Fd #include <string.h>
 .Ft char *
 .Fn strtok "char *str" "const char *sep"
+.Ft char *
+.Fn strtok_r "char *str" "const char *sep" "char **lasts"
 .Sh DESCRIPTION
 .Bf -symbolic
 This interface is obsoleted by strsep(3).

lib/libc/string/strtok_r.c

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 1988 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 = "from: @(#)strtok.c	5.8 (Berkeley) 2/24/91";*/
+static char *rcsid = "$Id: strtok_r.c,v 1.1 1996/11/12 02:03:14 jtc Exp $";
+#endif /* LIBC_SCCS and not lint */
+
+#include <string.h>
+
+char *
+strtok_r(s, delim, lasts)
+	register char *s;
+	register const char *delim;
+	register char **lasts;
+{
+	register char *spanp;
+	register int c, sc;
+	char *tok;
+
+	if (s == NULL && (s = *lasts) == NULL)
+		return (NULL);
+
+	/*
+	 * Skip (span) leading delimiters (s += strspn(s, delim), sort of).
+	 */
+cont:
+	c = *s++;
+	for (spanp = (char *)delim; (sc = *spanp++) != 0;) {
+		if (c == sc)
+			goto cont;
+	}
+
+	if (c == 0) {		/* no non-delimiter characters */
+		*lasts = NULL;
+		return (NULL);
+	}
+	tok = s - 1;
+
+	/*
+	 * Scan token (scan for delimiters: s += strcspn(s, delim), sort of).
+	 * Note that delim must have one NUL; we stop if we see that, too.
+	 */
+	for (;;) {
+		c = *s++;
+		spanp = (char *)delim;
+		do {
+			if ((sc = *spanp++) == c) {
+				if (c == 0)
+					s = NULL;
+				else
+					s[-1] = 0;
+				*lasts = s;
+				return (tok);
+			}
+		} while (sc != 0);
+	}
+	/* NOTREACHED */
+}