Some tweaks from jmc@ and describe better what recallocarray does;

help and ok from tom@ and deraadt@
author: otto <> 2017-03-07 06:07:50 +0000
committer: otto <> 2017-03-07 06:07:50 +0000
commit: 3c4f58bea7403d47518cc64d65cd733d3c607f8b (patch)
tree: 3d6e5d44117b13cf7f479d92d38c5aa2ad971117 /src/lib
parent: deb5b03f7173c1875345c8fd248a85078c16dc9f (diff)
download: openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.tar.gz
openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.tar.bz2
openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.zip
1 files changed, 16 insertions, 7 deletions
diff --git a/src/lib/libc/stdlib/malloc.3 b/src/lib/libc/stdlib/malloc.3
index 66de428cb0..e24a811bec 100644
--- a/src/lib/libc/stdlib/malloc.3
+++ b/src/lib/libc/stdlib/malloc.3
@@ -30,15 +30,16 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: malloc.3,v 1.102 2017/03/06 18:44:21 otto Exp $
+.\"     $OpenBSD: malloc.3,v 1.103 2017/03/07 06:07:50 otto Exp $
 .\"
-.Dd $Mdocdate: March 6 2017 $
+.Dd $Mdocdate: March 7 2017 $
 .Dt MALLOC 3
 .Os
 .Sh NAME
 .Nm malloc ,
 .Nm calloc ,
 .Nm reallocarray ,
+.Nm recallocarray ,
 .Nm realloc ,
 .Nm free
 .Nd memory allocation and deallocation
@@ -118,7 +119,9 @@ The
 .Fn recallocarray
 function is similar to
 .Fn reallocarray
-except that it takes care of clearing newly allocated and freed memory.
+except that it takes care of clearing newly allocated memory.
+Additionally, the memory that becomes unallocated while shrinking
+or moving existing allocations is erased.
 If
 .Fa ptr
 is a
@@ -135,9 +138,9 @@ pointer,
 .Fa oldnmemb
 must be a value such that
 .Fa oldnmemb
-* 
+*
 .Fa size
-is the size of an earlier allocation that returned
+is the size of the earlier allocation that returned
 .Fa ptr ,
 otherwise the behaviour is undefined.
 .Pp
@@ -204,7 +207,7 @@ to
 .Er ENOMEM .
 .Pp
 If
-.Fa ptr 
+.Fa ptr
 is not NULL and multiplying
 .Fa oldnmemb
 and
@@ -220,8 +223,10 @@ to
 .Sh IDIOMS
 Consider
 .Fn calloc
-or the extension
+or the extensions
 .Fn reallocarray
+and
+.Fn recallocarray
 when there is multiplication in the
 .Fa size
 argument of
@@ -547,6 +552,10 @@ The
 .Fn reallocarray
 function appeared in
 .Ox 5.6 .
+The
+.Fn recallocarray
+function appeared in
+.Ox 6.1 .
 .Sh CAVEATS
 When using
 .Fn malloc ,
author	otto <>	2017-03-07 06:07:50 +0000
committer	otto <>	2017-03-07 06:07:50 +0000
commit	3c4f58bea7403d47518cc64d65cd733d3c607f8b (patch)
tree	3d6e5d44117b13cf7f479d92d38c5aa2ad971117 /src/lib
parent	deb5b03f7173c1875345c8fd248a85078c16dc9f (diff)
download	openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.tar.gz openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.tar.bz2 openbsd-3c4f58bea7403d47518cc64d65cd733d3c607f8b.zip

diff --git a/src/lib/libc/stdlib/malloc.3 b/src/lib/libc/stdlib/malloc.3 index 66de428cb0..e24a811bec 100644 --- a/src/lib/libc/stdlib/malloc.3 +++ b/src/lib/libc/stdlib/malloc.3
@@ -30,15 +30,16 @@
30	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF	30	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31	.\" SUCH DAMAGE.	31	.\" SUCH DAMAGE.
32	.\"	32	.\"
33	.\" $OpenBSD: malloc.3,v 1.102 2017/03/06 18:44:21 otto Exp $	33	.\" $OpenBSD: malloc.3,v 1.103 2017/03/07 06:07:50 otto Exp $
34	.\"	34	.\"
35	.Dd $Mdocdate: March 6 2017 $	35	.Dd $Mdocdate: March 7 2017 $
36	.Dt MALLOC 3	36	.Dt MALLOC 3
37	.Os	37	.Os
38	.Sh NAME	38	.Sh NAME
39	.Nm malloc ,	39	.Nm malloc ,
40	.Nm calloc ,	40	.Nm calloc ,
41	.Nm reallocarray ,	41	.Nm reallocarray ,
		42	.Nm recallocarray ,
42	.Nm realloc ,	43	.Nm realloc ,
43	.Nm free	44	.Nm free
44	.Nd memory allocation and deallocation	45	.Nd memory allocation and deallocation
@@ -118,7 +119,9 @@ The
118	.Fn recallocarray	119	.Fn recallocarray
119	function is similar to	120	function is similar to
120	.Fn reallocarray	121	.Fn reallocarray
121	except that it takes care of clearing newly allocated and freed memory.	122	except that it takes care of clearing newly allocated memory.
		123	Additionally, the memory that becomes unallocated while shrinking
		124	or moving existing allocations is erased.
122	If	125	If
123	.Fa ptr	126	.Fa ptr
124	is a	127	is a
@@ -135,9 +138,9 @@ pointer,
135	.Fa oldnmemb	138	.Fa oldnmemb
136	must be a value such that	139	must be a value such that
137	.Fa oldnmemb	140	.Fa oldnmemb
138	*	141	*
139	.Fa size	142	.Fa size
140	is the size of an earlier allocation that returned	143	is the size of the earlier allocation that returned
141	.Fa ptr ,	144	.Fa ptr ,
142	otherwise the behaviour is undefined.	145	otherwise the behaviour is undefined.
143	.Pp	146	.Pp
@@ -204,7 +207,7 @@ to
204	.Er ENOMEM .	207	.Er ENOMEM .
205	.Pp	208	.Pp
206	If	209	If
207	.Fa ptr	210	.Fa ptr
208	is not NULL and multiplying	211	is not NULL and multiplying
209	.Fa oldnmemb	212	.Fa oldnmemb
210	and	213	and
@@ -220,8 +223,10 @@ to
220	.Sh IDIOMS	223	.Sh IDIOMS
221	Consider	224	Consider
222	.Fn calloc	225	.Fn calloc
223	or the extension	226	or the extensions
224	.Fn reallocarray	227	.Fn reallocarray
		228	and
		229	.Fn recallocarray
225	when there is multiplication in the	230	when there is multiplication in the
226	.Fa size	231	.Fa size
227	argument of	232	argument of
@@ -547,6 +552,10 @@ The
547	.Fn reallocarray	552	.Fn reallocarray
548	function appeared in	553	function appeared in
549	.Ox 5.6 .	554	.Ox 5.6 .
		555	The
		556	.Fn recallocarray
		557	function appeared in
		558	.Ox 6.1 .
550	.Sh CAVEATS	559	.Sh CAVEATS
551	When using	560	When using
552	.Fn malloc ,	561	.Fn malloc ,