libc: add mempcpy(3) and wmempcpy(3)

Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D31180

include/string.h

@@ -66,6 +66,9 @@ void	*memcpy(void * __restrict, const void * __restrict, size_t);
 void	*memmem(const void *, size_t, const void *, size_t) __pure;
 #endif
 void	*memmove(void *, const void *, size_t);
+#if __BSD_VISIBLE
+void	*mempcpy(void * __restrict, const void * __restrict, size_t);
+#endif
 void	*memset(void *, int, size_t);
 #if __POSIX_VISIBLE >= 200809
 char	*stpcpy(char * __restrict, const char * __restrict);

include/wchar.h

@@ -172,6 +172,9 @@ wchar_t	*wmemchr(const wchar_t *, wchar_t, size_t) __pure;
 int	wmemcmp(const wchar_t *, const wchar_t *, size_t) __pure;
 wchar_t	*wmemcpy(wchar_t * __restrict, const wchar_t * __restrict, size_t);
 wchar_t	*wmemmove(wchar_t *, const wchar_t *, size_t);
+#if __BSD_VISIBLE
+wchar_t	*wmempcpy(wchar_t * __restrict, const wchar_t * __restrict, size_t);
+#endif
 wchar_t	*wmemset(wchar_t *, wchar_t, size_t);
 int	wprintf(const wchar_t * __restrict, ...);
 int	wscanf(const wchar_t * __restrict, ...);

lib/libc/string/Makefile.inc

@@ -10,7 +10,7 @@ CFLAGS+= -I${LIBC_SRCTOP}/locale
 MISRCS+=bcmp.c bcopy.c bzero.c explicit_bzero.c \
 	ffs.c ffsl.c ffsll.c fls.c flsl.c flsll.c \
 	memccpy.c memchr.c memrchr.c memcmp.c \
-	memcpy.c memmem.c memmove.c memset.c memset_s.c \
+	memcpy.c memmem.c memmove.c mempcpy.c memset.c memset_s.c \
 	stpcpy.c stpncpy.c strcasecmp.c \
 	strcat.c strcasestr.c strchr.c strchrnul.c strcmp.c strcoll.c strcpy.c\
 	strcspn.c strdup.c strerror.c strlcat.c strlcpy.c strlen.c strmode.c \
@@ -25,7 +25,7 @@ MISRCS+=bcmp.c bcopy.c bzero.c explicit_bzero.c \
 	wcsncpy.c wcsnlen.c wcspbrk.c \
 	wcsrchr.c wcsspn.c wcsstr.c wcstok.c wcswidth.c wcsxfrm.c wmemchr.c \
 	wmemcmp.c \
-	wmemcpy.c wmemmove.c wmemset.c
+	wmemcpy.c wmemmove.c wmempcpy.c wmemset.c
 
 SYM_MAPS+=	${LIBC_SRCTOP}/string/Symbol.map
 
@@ -50,6 +50,7 @@ MLINKS+=ffs.3 ffsl.3 \
 	ffs.3 flsll.3
 MLINKS+=index.3 rindex.3
 MLINKS+=memchr.3 memrchr.3
+MLINKS+=memcpy.3 mempcpy.3
 MLINKS+=memset.3 memset_s.3
 MLINKS+=strcasecmp.3 strncasecmp.3 \
 	strcasecmp.3 strcasecmp_l.3 \
@@ -101,4 +102,5 @@ MLINKS+=wmemchr.3 wcpcpy.3 \
 	wmemchr.3 wmemcmp.3 \
 	wmemchr.3 wmemcpy.3 \
 	wmemchr.3 wmemmove.3 \
+	wmemchr.3 wmempcpy.3 \
 	wmemchr.3 wmemset.3

lib/libc/string/Symbol.map

@@ -114,6 +114,11 @@ FBSD_1.6 {
 	strerror_l;
 };
 
+FBSD_1.7 {
+	mempcpy;
+	wmempcpy;
+};
+
 FBSDprivate_1.0 {
 	__strtok_r;
 };

lib/libc/string/memcpy.3

@@ -32,7 +32,7 @@
 .\"     @(#)memcpy.3	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd June 4, 1993
+.Dd July 14, 2021
 .Dt MEMCPY 3
 .Os
 .Sh NAME
@@ -44,11 +44,15 @@
 .In string.h
 .Ft void *
 .Fn memcpy "void *dst" "const void *src" "size_t len"
+.Ft void *
+.Fn mempcpy "void *dst" "const void *src" "size_t len"
 .Sh DESCRIPTION
 The
 .Fn memcpy
-function
+and
-copies
+.Fn mempcpy
+functions
+copy
 .Fa len
 bytes from string
 .Fa src
@@ -65,12 +69,17 @@ The
 function
 returns the original value of
 .Fa dst .
+.Pp
+The
+.Fn mempcpy
+function returns a pointer to the byte after the last written byte.
 .Sh SEE ALSO
 .Xr bcopy 3 ,
 .Xr memccpy 3 ,
 .Xr memmove 3 ,
 .Xr strcpy 3 ,
 .Xr wmemcpy 3
+.Xr wmempcpy 3
 .Sh STANDARDS
 The
 .Fn memcpy
@@ -80,7 +89,9 @@ conforms to
 .Sh BUGS
 In this implementation
 .Fn memcpy
-is implemented using
+and
+.Fn mempcpy
+are implemented using
 .Xr bcopy 3 ,
 and therefore the strings may overlap.
 On other systems, copying overlapping strings may produce surprises.

lib/libc/string/mempcpy.c

@@ -0,0 +1,41 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2021 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <string.h>
+
+void *
+mempcpy(void *__restrict dst, const void *__restrict src, size_t len)
+{
+	return ((char *)memcpy(dst, src, len) + len);
+}

lib/libc/string/wmemchr.3

@@ -35,7 +35,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd March 4, 2009
+.Dd July 14, 2021
 .Dt WMEMCHR 3
 .Os
 .Sh NAME
@@ -43,6 +43,7 @@
 .Nm wmemcmp ,
 .Nm wmemcpy ,
 .Nm wmemmove ,
+.Nm wmempcpy ,
 .Nm wmemset ,
 .Nm wcpcpy ,
 .Nm wcpncpy ,
@@ -79,6 +80,8 @@
 .Ft wchar_t *
 .Fn wmemmove "wchar_t *s1" "const wchar_t *s2" "size_t n"
 .Ft wchar_t *
+.Fn wmempcpy "wchar_t * restrict s1" "const wchar_t * restrict s2" "size_t n"
+.Ft wchar_t *
 .Fn wmemset "wchar_t *s" "wchar_t c" "size_t n"
 .Ft wchar_t *
 .Fn wcpcpy "wchar_t *s1" "wchar_t *s2"
@@ -168,7 +171,8 @@ and
 which conform to
 .St -p1003.1-2008 ;
 and
-.Fn wcslcat
+.Fn wcslcat ,
-and
 .Fn wcslcpy ,
+and
+.Fn wmempcpy ,
 which are extensions.

lib/libc/string/wmempcpy.c

@@ -0,0 +1,42 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2021 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <string.h>
+#include <wchar.h>
+
+wchar_t *
+wmempcpy(wchar_t *__restrict dst, const wchar_t *__restrict src, size_t len)
+{
+	return (wmemcpy(dst, src, len) + len);
+}