move reallocarray() to a seperate file so that -portable applications

can avoid reinventing the wheel
ok guenther schwarze

src/lib/libc/stdlib/Makefile.inc

@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.52 2014/04/22 14:26:26 tedu Exp $
+#	$OpenBSD: Makefile.inc,v 1.53 2014/05/08 21:43:49 deraadt Exp $
 
 # stdlib sources
 .PATH: ${LIBCSRCDIR}/arch/${MACHINE_CPU}/stdlib ${LIBCSRCDIR}/stdlib
@@ -6,11 +6,12 @@
 SRCS+=	a64l.c abort.c atexit.c atoi.c atof.c atol.c atoll.c bsearch.c \
 	cfree.c exit.c ecvt.c gcvt.c getenv.c getopt_long.c \
 	getsubopt.c hcreate.c heapsort.c imaxabs.c imaxdiv.c l64a.c llabs.c \
-	lldiv.c lsearch.c malloc.c merge.c posix_pty.c qsort.c radixsort.c \
-	rand.c random.c realpath.c setenv.c strtoimax.c strtol.c \
-	strtoll.c strtonum.c strtoul.c strtoull.c strtoumax.c system.c \
-	tfind.c tsearch.c _rand48.c drand48.c erand48.c jrand48.c lcong48.c \
-	lrand48.c mrand48.c nrand48.c seed48.c srand48.c qabs.c qdiv.c _Exit.c
+	lldiv.c lsearch.c malloc.c reallocarray.c merge.c posix_pty.c \
+	qsort.c radixsort.c rand.c random.c realpath.c setenv.c strtoimax.c \
+	strtol.c strtoll.c strtonum.c strtoul.c strtoull.c strtoumax.c \
+	system.c tfind.c tsearch.c _rand48.c drand48.c erand48.c jrand48.c \
+	lcong48.c lrand48.c mrand48.c nrand48.c seed48.c srand48.c qabs.c \
+	qdiv.c _Exit.c
 
 .if (${MACHINE_CPU} == "i386")
 SRCS+=	abs.S div.S labs.S ldiv.S

src/lib/libc/stdlib/malloc.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: malloc.c,v 1.160 2014/05/07 20:07:59 halex Exp $	*/
+/*	$OpenBSD: malloc.c,v 1.161 2014/05/08 21:43:49 deraadt Exp $	*/
 /*
  * Copyright (c) 2008, 2010, 2011 Otto Moerbeek <otto@drijf.net>
  * Copyright (c) 2012 Matthew Dempsky <matthew@openbsd.org>
@@ -1424,17 +1424,6 @@ calloc(size_t nmemb, size_t size)
 	return r;
 }
 
-void *
-reallocarray(void *optr, size_t nmemb, size_t size)
-{
-	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
-	    nmemb > 0 && SIZE_MAX / nmemb < size) {
-		errno = ENOMEM;
-		return NULL;
-	}
-	return realloc(optr, size * nmemb);
-}
-
 static void *
 mapalign(struct dir_info *d, size_t alignment, size_t sz, int zero_fill)
 {

src/lib/libc/stdlib/reallocarray.c

@@ -0,0 +1,38 @@
+/*	$OpenBSD: reallocarray.c,v 1.1 2014/05/08 21:43:49 deraadt Exp $	*/
+/*
+ * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+/*
+ * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
+ * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
+ */
+#define MUL_NO_OVERFLOW	(1UL << (sizeof(size_t) * 4))
+
+void *
+reallocarray(void *optr, size_t nmemb, size_t size)
+{
+	if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+	    nmemb > 0 && SIZE_MAX / nmemb < size) {
+		errno = ENOMEM;
+		return NULL;
+	}
+	return realloc(optr, size * nmemb);
+}