[svn-r9598] Purpose:

    New internal feature

Description:
    Add a "release" routine to the skip lists, which releases all the nodes
in the skip list, but keeps the skip list active.

Platforms tested:
    FreeBSD 4.10 (sleipnir)
    Linux 2.4 (verbena)
    Too minor to require h5committest

4 files changed, 82 insertions, 16 deletions

diff --git a/src/H5C.c b/src/H5C.c
index 120e2c1..af96125 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -2486,15 +2486,9 @@ H5C_flush_cache(H5F_t *  f,
 
         if(cache_ptr->slist_ptr) {
 
-            /* XXX: Replace this with call to H5SL_free() when its implemented... */
-            H5SL_close(cache_ptr->slist_ptr);
+            /* Release all nodes from skip list, but keep list active */
+            H5SL_release(cache_ptr->slist_ptr);
 
-            /* XXX: ...and remove this call */
-            if ( (cache_ptr->slist_ptr = H5SL_create(H5SL_TYPE_HADDR,0.5,16)) 
-                 == NULL ) {
-
-                HGOTO_ERROR(H5E_CACHE, H5E_CANTCREATE, FAIL, "can't create skip list.")
-            }
         }
         cache_ptr->slist_len = 0;
         cache_ptr->slist_size = 0;
diff --git a/src/H5SL.c b/src/H5SL.c
index 9370ba7..eea4cdc 100644
--- a/src/H5SL.c
+++ b/src/H5SL.c
@@ -673,6 +673,59 @@ H5SL_item(H5SL_node_t *slist_node)
 
 /*--------------------------------------------------------------------------
  NAME
+    H5SL_release
+ PURPOSE
+    Release all nodes from a skip list
+ USAGE
+    herr_t H5SL_release(slist)
+        H5SL_t *slist;            IN/OUT: Pointer to skip list to release nodes
+
+ RETURNS
+    Returns non-negative on success, negative on failure.
+ DESCRIPTION
+    Release all the nodes in a skip list.  Any objects left in the skip list
+    nodes are not deallocated.
+ GLOBAL VARIABLES
+ COMMENTS, BUGS, ASSUMPTIONS
+ EXAMPLES
+ REVISION LOG
+--------------------------------------------------------------------------*/
+herr_t
+H5SL_release(H5SL_t *slist)
+{
+    H5SL_node_t *node, *next_node;      /* Pointers to skip list nodes */
+    size_t u;                   /* Local index variable */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SL_release);
+
+    /* Check args */
+    assert(slist);
+
+    /* Check internal consistency */
+    /* (Pre-condition) */
+
+    /* Free skip list nodes */
+    node=slist->header->forward[0];
+    while(node!=NULL) {
+        next_node=node->forward[0];
+        H5MM_xfree(node);
+        node=next_node;
+    } /* end while */
+
+    /* Reset the header pointers */
+    for(u=0; u<slist->max_level; u++)
+        slist->header->forward[u]=NULL;
+
+    /* Reset the dynamic internal fields */
+    slist->curr_level=-1;
+    slist->nobjs=0;
+
+    FUNC_LEAVE_NOAPI(SUCCEED);
+} /* end H5SL_release() */
+
+
+/*--------------------------------------------------------------------------
+ NAME
     H5SL_close
  PURPOSE
     Close a skip list, deallocating it.
@@ -693,8 +746,6 @@ H5SL_item(H5SL_node_t *slist_node)
 herr_t
 H5SL_close(H5SL_t *slist)
 {
-    H5SL_node_t *node, *next_node;      /* Pointers to skip list nodes */
-
     FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SL_close);
 
     /* Check args */
@@ -704,12 +755,10 @@ H5SL_close(H5SL_t *slist)
     /* (Pre-condition) */
 
     /* Free skip list nodes */
-    node=slist->header;
-    while(node!=NULL) {
-        next_node=node->forward[0];
-        H5MM_xfree(node);
-        node=next_node;
-    } /* end while */
+    H5SL_release(slist);        /* always succeeds */
+
+    /* Release header node */
+    H5MM_xfree(slist->header);
 
     /* Free skip list object */
     H5FL_FREE(H5SL_t,slist);
diff --git a/src/H5SLprivate.h b/src/H5SLprivate.h
index 94e2b4d..e6f64d8 100644
--- a/src/H5SLprivate.h
+++ b/src/H5SLprivate.h
@@ -60,6 +60,7 @@ H5_DLL void *H5SL_search(H5SL_t *slist, void *key);
 H5_DLL H5SL_node_t *H5SL_first(H5SL_t *slist);
 H5_DLL H5SL_node_t *H5SL_next(H5SL_node_t *slist_node);
 H5_DLL void *H5SL_item(H5SL_node_t *slist_node);
+H5_DLL herr_t H5SL_release(H5SL_t *slist);
 H5_DLL herr_t H5SL_close(H5SL_t *slist);
 
 #endif /* _H5HPprivate_H */
diff --git a/test/tskiplist.c b/test/tskiplist.c
index cf88daf..dfd73a9 100644
--- a/test/tskiplist.c
+++ b/test/tskiplist.c
@@ -235,6 +235,28 @@ test_skiplist_insert_many(void)
         VERIFY(*found_item,rand_num[u],"H5SL_search");
     } /* end for */
 
+    /* Release all the items from the list */
+    ret=H5SL_release(slist);
+    CHECK(ret, FAIL, "H5SL_release");
+
+    /* Check that the skip list has no elements */
+    num=H5SL_count(slist);
+    VERIFY(num, 0, "H5SL_count");
+
+    /* Insert many objects into the skip list */
+    for(u=0; u<NUM_ELEMS; u++) {
+        ret=H5SL_insert(slist,&rand_num[u],&rand_num[u]);
+        CHECK(ret, FAIL, "H5SL_insert");
+    } /* end for */
+
+    /* Check that the skip list has correct # of elements */
+    num=H5SL_count(slist);
+    VERIFY(num, NUM_ELEMS, "H5SL_count");
+
+    /* Release all the items from the list */
+    ret=H5SL_release(slist);
+    CHECK(ret, FAIL, "H5SL_release");
+
     /* Close the skip list */
     ret=H5SL_close(slist);
     CHECK(ret, FAIL, "H5SL_close");