On Tue, Jun 27, 2006 at 01:30:06PM +0200, [EMAIL PROTECTED] wrote:
> Hi,
>
> the attached patch against CVS saves around 2,5 MB of allocated ac-trie
> heap memory with a recent database. It does two things:
>
> - dont allocate a trans[256] array for last nodes, since those transitions
> are never used.
>
> - dont use the cli_ac_node->islast flag in each node, since it is redundant
> to the
> cli_ac_node->list pointer, instead check for a set cli_ac_node->list
> pointer
> to find out about a last node
Hi,
the proposed patch caused a segfault on program termination. Please use instead
the attached patch for testing. Sorry for the inconvenience ...
Best Regards
Peter
--
Peter Vollmer
Software Engineer
Innominate Security Technologies AG /device attached security/
tel: +49.30.6392-3687
fax: +49.30.6392-3307
Albert-Einstein-Str. 14
D-12489 Berlin, Germany
www.innominate.com
? -p0
? patch_ac_lastnodes
Index: libclamav/clamav.h
===================================================================
RCS file: /cvsroot/clamav/clamav-devel/libclamav/clamav.h,v
retrieving revision 1.62
diff -b -w -u -r1.62 clamav.h
--- libclamav/clamav.h 26 Jun 2006 18:26:32 -0000 1.62
+++ libclamav/clamav.h 30 Jun 2006 13:52:48 -0000
@@ -121,9 +121,9 @@
};
struct cli_ac_node {
- char islast;
struct cli_ac_patt *list;
- struct cli_ac_node *trans[256], *fail;
+ struct cli_ac_node **trans;
+ struct cli_ac_node*fail;
};
struct cli_md5_node {
Index: libclamav/matcher-ac.c
===================================================================
RCS file: /cvsroot/clamav/clamav-devel/libclamav/matcher-ac.c,v
retrieving revision 1.20
diff -b -w -u -r1.20 matcher-ac.c
--- libclamav/matcher-ac.c 26 Jun 2006 18:26:32 -0000 1.20
+++ libclamav/matcher-ac.c 30 Jun 2006 13:52:48 -0000
@@ -64,7 +64,13 @@
cli_dbgmsg("Unable to allocate pattern node (%d)\n",
sizeof(struct cli_matcher));
return CL_EMEM;
}
-
+ if (i < ac_depth-1) {
+ next->trans = (struct cli_ac_node **) cli_calloc(256,
sizeof(struct cli_ac_node*));
+ if(!next->trans) {
+ cli_dbgmsg("Unable to allocate pattern node trans array\n");
+ return CL_EMEM;
+ }
+ }
root->ac_nodes++;
root->ac_nodetable = (struct cli_ac_node **)
cli_realloc(root->ac_nodetable, (root->ac_nodes) * sizeof(struct cli_ac_node
*));
if(root->ac_nodetable == NULL) {
@@ -79,9 +85,8 @@
pos = next;
}
- pos->islast = 1;
-
pattern->next = pos->list;
+ /* list pointer !=NULL also defines a last node */
pos->list = pattern;
return CL_SUCCESS;
@@ -142,7 +147,8 @@
}
while((node = cli_dequeue(&bfs))) {
- if(node->islast)
+ /* last node ? */
+ if(node->list)
continue;
for(i = 0; i < 256; i++) {
@@ -216,15 +222,19 @@
for(i = 0; i < root->ac_nodes; i++) {
cli_freepatt(root->ac_nodetable[i]->list);
+ if (root->ac_nodetable[i]->trans)
+ free(root->ac_nodetable[i]->trans);
free(root->ac_nodetable[i]);
}
if(root->ac_nodetable)
free(root->ac_nodetable);
- if(root->ac_root)
+ if(root->ac_root) {
+ free(root->ac_root->trans);
free(root->ac_root);
}
+}
inline static int cli_findpos(const char *buffer, unsigned int depth, unsigned
int offset, unsigned int length, const struct cli_ac_patt *pattern)
{
@@ -313,8 +323,8 @@
for(i = 0; i < length; i++) {
current = current->trans[(unsigned char) buffer[i] & 0xff];
-
- if(current->islast) {
+ /* last node ? */
+ if(current->list) {
position = i - ac_depth + 1;
pt = current->list;
Index: libclamav/readdb.c
===================================================================
RCS file: /cvsroot/clamav/clamav-devel/libclamav/readdb.c,v
retrieving revision 1.78
diff -b -w -u -r1.78 readdb.c
--- libclamav/readdb.c 26 Jun 2006 18:26:32 -0000 1.78
+++ libclamav/readdb.c 30 Jun 2006 13:52:48 -0000
@@ -513,7 +513,11 @@
cli_errmsg("Can't initialise AC pattern matcher\n");
return CL_EMEM;
}
-
+ root->ac_root->trans = (struct cli_ac_node **) cli_calloc(256,
sizeof(struct cli_ac_node*));
+ if(!root->ac_root->trans) {
+ cli_errmsg("Can't initialise AC trans array\n");
+ return CL_EMEM;
+ }
if(!root->ac_only) {
cli_dbgmsg("Initializing BM tables of root[%d]\n", i);
if((ret = cli_bm_init(root))) {
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