ref: 5e7ad208e35643e18deb505465604e2ed3b149cf
parent: 38b272ffbbdaae276d636aec4ef84af407d16181
author: suzuki toshiya <[email protected]>
date: Sun Jan 9 18:09:36 EST 2011
[cache] Fix Savannah bug #31923, patch drafted by Harsha. When a node comparator changes the cached nodes during the search of a node matching with queried properties, the pointers obtained before the functon should be updated to prevent the dereference to freed or reallocated nodes. To minimize the rescan of the linked list, the update is executed when the comparator notifies the change of cached nodes. This change depends previous change: 38b272ffbbdaae276d636aec4ef84af407d16181 * src/cache/ftccache.h (FTC_CACHE_LOOKUP_CMP): Rescan the top node if the cached nodes are changed. * src/cache/ftccache.c (FTC_Cache_Lookup): Ditto.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,22 @@
2010-01-09 suzuki toshiya <[email protected]>
+ [cache] Fix Savannah bug #31923, patch drafted by Harsha.
+
+ When a node comparator changes the cached nodes during the
+ search of a node matching with queried properties, the
+ pointers obtained before the functon should be updated to
+ prevent the dereference to freed or reallocated nodes.
+ To minimize the rescan of the linked list, the update is
+ executed when the comparator notifies the change of cached
+ nodes. This change depends previous change:
+ 38b272ffbbdaae276d636aec4ef84af407d16181
+
+ * src/cache/ftccache.h (FTC_CACHE_LOOKUP_CMP): Rescan the
+ top node if the cached nodes are changed.
+ * src/cache/ftccache.c (FTC_Cache_Lookup): Ditto.
+
+2010-01-09 suzuki toshiya <[email protected]>
+
[cache] Notice if a cache query induced the node list change.
Some node comparators (comparing the cache node content and
--- a/src/cache/ftccache.c
+++ b/src/cache/ftccache.c
@@ -498,7 +498,11 @@
if ( cache == NULL || anode == NULL )
return FTC_Err_Invalid_Argument;
+ /* Go to the `top' node of the list sharing same masked hash */
bucket = pnode = FTC_NODE__TOP_FOR_HASH( cache, hash );
+
+ /* Lookup a node with exactly same hash and queried properties. */
+ /* NOTE: _nodcomp() may change the linked list to reduce memory. */
for (;;)
{node = *pnode;
@@ -512,6 +516,25 @@
pnode = &node->link;
}
+ if ( list_changed )
+ {+ /* Update bucket by modified linked list */
+ bucket = pnode = FTC_NODE__TOP_FOR_HASH( cache, hash );
+
+ /* Update pnode by modified linked list */
+ while ( *pnode != node )
+ {+ if ( *pnode == NULL )
+ {+ FT_ERROR(("oops!!! node missing"));+ goto NewNode;
+ }
+ else
+ pnode = &((*pnode)->link);
+ }
+ }
+
+ /* Reorder the list to move the found node to the `top' */
if ( node != *bucket )
{*pnode = node->link;
--- a/src/cache/ftccache.h
+++ b/src/cache/ftccache.h
@@ -224,8 +224,12 @@
\
error = FTC_Err_Ok; \
node = NULL; \
+ \
+ /* Go to the `top' node of the list sharing same masked hash */ \
_bucket = _pnode = FTC_NODE__TOP_FOR_HASH( _cache, _hash ); \
\
+ /* Lookup a node with exactly same hash and queried properties. */ \
+ /* NOTE: _nodcomp() may change the linked list to reduce memory. */ \
for (;;) \
{ \_node = *_pnode; \
@@ -239,6 +243,25 @@
_pnode = &_node->link; \
} \
\
+ if ( _list_changed ) \
+ { \+ /* Update _bucket by possibly modified linked list */ \
+ _bucket = _pnode = FTC_NODE__TOP_FOR_HASH( _cache, _hash ); \
+ \
+ /* Update _pnode by possibly modified linked list */ \
+ while ( *_pnode != _node ) \
+ { \+ if ( *_pnode == NULL ) \
+ { \+ FT_ERROR(("oops!!! node missing")); \+ goto _NewNode; \
+ } \
+ else \
+ _pnode = &((*_pnode)->link); \
+ } \
+ } \
+ \
+ /* Reorder the list to move the found node to the `top' */ \
if ( _node != *_bucket ) \
{ \*_pnode = _node->link; \
@@ -246,6 +269,7 @@
*_bucket = _node; \
} \
\
+ /* Update MRU list */ \
{ \FTC_Manager _manager = _cache->manager; \
void* _nl = &_manager->nodes_list; \