Add and document ffsl(), fls() and flsl().

include/strings.h

@@ -42,6 +42,9 @@ int	 bcmp(const void *, const void *, size_t);	/* LEGACY */
 void	 bcopy(const void *, void *, size_t);		/* LEGACY */
 void	 bzero(void *, size_t);				/* LEGACY */
 int	 ffs(int);
+int	 ffsl(long);
+int	 fls(int);
+int	 flsl(long);
 char	*index(const char *, int);			/* LEGACY */
 char	*rindex(const char *, int);			/* LEGACY */
 int	 strcasecmp(const char *, const char *);

lib/libc/Makefile

@@ -83,8 +83,8 @@ SRCS+=	${_src}
 KQSRCS=	adddi3.c anddi3.c ashldi3.c ashrdi3.c cmpdi2.c divdi3.c iordi3.c \
 	lshldi3.c lshrdi3.c moddi3.c muldi3.c negdi2.c notdi2.c qdivrem.c \
 	subdi3.c ucmpdi2.c udivdi3.c umoddi3.c xordi3.c
-KSRCS=	bcmp.c ffs.c index.c mcount.c rindex.c strcat.c strcmp.c strcpy.c \
+KSRCS=	bcmp.c ffs.c ffsl.c fls.c flsl.c index.c mcount.c rindex.c \
-	strlen.c strncpy.c
+	strcat.c strcmp.c strcpy.c strlen.c strncpy.c
 
 libkern: libkern.gen libkern.${MACHINE_ARCH}
 

lib/libc/string/Makefile.inc

@@ -6,7 +6,8 @@
 CFLAGS+= -I${.CURDIR}/locale
 
 # machine-independent string sources
-MISRCS+=bcmp.c bcopy.c bzero.c ffs.c index.c memccpy.c memchr.c memcmp.c \
+MISRCS+=bcmp.c bcopy.c bzero.c ffs.c ffsl.c fls.c flsl.c index.c memccpy.c \
+	memchr.c memcmp.c \
 	memcpy.c memmove.c memset.c rindex.c stpcpy.c strcasecmp.c strcat.c \
 	strchr.c strcmp.c strcoll.c strcpy.c strcspn.c strdup.c strerror.c \
 	strlcat.c strlcpy.c strlen.c strmode.c strncat.c strncmp.c strncpy.c \
@@ -32,6 +33,9 @@ MAN+=	bcmp.3 bcopy.3 bstring.3 bzero.3 ffs.3 index.3 memccpy.3 memchr.3 \
 	strspn.3 strstr.3 strtok.3 strxfrm.3 swab.3 wcscoll.3 wcstok.3 \
 	wcswidth.3 wcsxfrm.3 wmemchr.3
 
+MLINKS+=ffs.3 ffsl.3
+MLINKS+=ffs.3 fls.3
+MLINKS+=ffs.3 flsl.3
 MLINKS+=index.3 rindex.3
 MLINKS+=strcasecmp.3 strncasecmp.3
 MLINKS+=strcat.3 strncat.3

lib/libc/string/ffs.3

@@ -38,23 +38,44 @@
 .Dt FFS 3
 .Os
 .Sh NAME
-.Nm ffs
+.Nm ffs ,
-.Nd find first bit set in a bit string
+.Nm ffsl ,
+.Nm fls ,
+.Nm flsl
+.Nd find first or last bit set in a bit string
 .Sh LIBRARY
 .Lb libc
 .Sh SYNOPSIS
 .In strings.h
 .Ft int
 .Fn ffs "int value"
+.Ft int
+.Fn ffsl "long value"
+.Ft int
+.Fn fls "int value"
+.Ft int
+.Fn flsl "long value"
 .Sh DESCRIPTION
 The
 .Fn ffs
-function finds the first bit set in
+and
+.Fn ffsl
+functions find the first bit set in
 .Fa value
-and returns the index of that bit.
+and return the index of that bit.
+.Pp
+The
+.Fn fls
+and
+.Fn flsl
+functions find the last bit set in
+.Fa value
+and return the index of that bit.
+.Pp
 Bits are numbered starting from 1, starting at the right-most
-bit.
+(least significant) bit.
-A return value of 0 means that the argument was zero.
+A return value of zero from any of these functions means that the
+argument was zero.
 .Sh SEE ALSO
 .Xr bitstring 3
 .Sh HISTORY
@@ -69,3 +90,11 @@ before it was moved to
 for
 .St -p1003.1-2001
 compliance.
+.Pp
+The
+.Fn ffsl ,
+.Fn fls
+and
+.Fn flsl
+functions appeared in
+.Fx 5.3 .

lib/libc/string/ffs.c

@@ -40,7 +40,7 @@ __FBSDID("$FreeBSD$");
 #include <strings.h>
 
 /*
- * ffs -- vax ffs instruction
+ * Find First Set bit
  */
 int
 ffs(int mask)
@@ -50,6 +50,6 @@ ffs(int mask)
 	if (mask == 0)
 		return(0);
 	for (bit = 1; !(mask & 1); bit++)
-		mask >>= 1;
+		(unsigned int)mask >>= 1;
-	return(bit);
+	return (bit);
 }

lib/libc/string/ffsl.c

@@ -0,0 +1,52 @@
+/*-
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <strings.h>
+
+/*
+ * Find First Set bit
+ */
+int
+ffsl(long mask)
+{
+	int bit;
+
+	if (mask == 0)
+		return(0);
+	for (bit = 1; !(mask & 1); bit++)
+		(unsigned long)mask >>= 1;
+	return (bit);
+}

lib/libc/string/fls.c

@@ -0,0 +1,52 @@
+/*-
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <strings.h>
+
+/*
+ * Find Last Set bit
+ */
+int
+fls(int mask)
+{
+	int bit;
+
+	if (mask == 0)
+		return (0);
+	for (bit = 1; mask != 1; bit++)
+		(unsigned int)mask >>= 1;
+	return (bit);
+}

lib/libc/string/flsl.c

@@ -0,0 +1,52 @@
+/*-
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <strings.h>
+
+/*
+ * Find Last Set bit
+ */
+int
+flsl(long mask)
+{
+	int bit;
+
+	if (mask == 0)
+		return (0);
+	for (bit = 1; mask != 1; bit++)
+		(unsigned long)mask >>= 1;
+	return (bit);
+}