Stefan Sperling <stsp_at_elego.de
<mailto:stsp_at_elego.de?Subject=Re:%20svn%20commit:%20r987869%20-%20/subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c>>
wrote:
On Sun, Aug 22, 2010 at 11:37:38AM -0000, stefan2_at_apache.org wrote:
/> Author: stefan2 /
/> Date: Sun Aug 22 11:37:38 2010 /
/> New Revision: 987869 /
/> /
/> URL: http://svn.apache.org/viewvc?rev=987869&view=rev
<http://svn.apache.org/viewvc?rev=987869&view=rev> /
/> Log: /
/> Fix VisualStudio build: memory size calculation for variable size /
/> arrays is not portable. /
/> /
/> * subversion/libsvn_fs_fs/temp_serializer.c /
/> (serialize_dir, serialize_txdelta_ops): fix array size calculation /
/> /
/> Modified: /
/>
subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c
/
/> /
/> Modified:
subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c
/
/> URL:
http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c?rev=987869&r1=987868&r2=987869&view=diff
<http://svn.apache.org/viewvc/subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c?rev=987869&r1=987868&r2=987869&view=diff>
/
/>
==============================================================================
/
/> ---
subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c
(original) /
/> +++
subversion/branches/performance/subversion/libsvn_fs_fs/temp_serializer.c
Sun Aug 22 11:37:38 2010 /
/> @@ -272,7 +272,7 @@ serialize_dir(apr_hash_t *entries, apr_p /
/> /
/> /* calculate sizes */ /
/> apr_size_t count = apr_hash_count(entries); /
/> - apr_size_t entries_len = sizeof(svn_fs_dirent_t*[count]); /
/> + apr_size_t entries_len = count * sizeof(svn_fs_dirent_t*[1]); /
Do you really want the second asterisk in that line?
It looks like you really want this:
+ apr_size_t entries_len = count * sizeof(svn_fs_dirent_t[1]);
No, it actually is an array of pointers. So, every element can be
serialized along with all its sub-elements as a single, contiguous
chunk of memory.
/> /
/> /* copy the hash entries to an auxilliary struct of known layout */ /
/> hash_data.count = count; /
/> @@ -422,7 +422,7 @@ serialize_txdelta_ops(svn_temp_serialize /
/> /* the ops form a simple chunk of memory with no further references
*/ /
/> svn_temp_serializer__push(context, /
/> (const void * const *)ops, /
/> - sizeof(svn_txdelta_op_t[count])); /
/> + count * sizeof(svn_txdelta_op_t[1])); /
Because you're not using the extra asterisk here, either.
I picked up the count*sizeof(T[1]) idiom from come STL implementations.
They were probably working around some non-standard compiler behavior
somewhere. Since that turned out to be unnecessary, I dropped the confusing
[1] in r988898.
-- Stefan^2.
