befs_btree_find(), the only caller of befs_find_key(), only cares about if
the return from that function is BEFS_BT_MATCH or not. It never uses the
partial match given with BEFS_BT_PARMATCH. Make the overflow return clearer
by having BEFS_BT_OVERFLOW instead of BEFS_BT_PARMATCH.
Signed-off-by: Luis de Bethencourt <lui...@osg.samsung.com>
---
v3: check for BEFS_BT_OVERFLOW instead of value == 0
Hi,
Switching to using BEFS_BT_OVERFLOW. This makes logic of befs_find_key()
clearer.
Thanks,
Luis
fs/befs/befs.h | 2 +-
fs/befs/btree.c | 38 ++++++++++++++++----------------------
2 files changed, 17 insertions(+), 23 deletions(-)
diff --git a/fs/befs/befs.h b/fs/befs/befs.h
index c5c6cd1..a8ca7fc 100644
--- a/fs/befs/befs.h
+++ b/fs/befs/befs.h
@@ -79,7 +79,7 @@ enum befs_err {
BEFS_BT_END,
BEFS_BT_EMPTY,
BEFS_BT_MATCH,
- BEFS_BT_PARMATCH,
+ BEFS_BT_OVERFLOW,
BEFS_BT_NOT_FOUND
};
diff --git a/fs/befs/btree.c b/fs/befs/btree.c
index 3f1a391..27b0336 100644
--- a/fs/befs/btree.c
+++ b/fs/befs/btree.c
@@ -281,9 +281,9 @@ befs_btree_find(struct super_block *sb, const
befs_data_stream *ds,
while (!befs_leafnode(this_node)) {
res = befs_find_key(sb, this_node, key, &node_off);
- if (res == BEFS_BT_NOT_FOUND)
+ /* if no key set, try the overflow node */
+ if (res == BEFS_BT_OVERFLOW)
node_off = this_node->head.overflow;
- /* if no match, go to overflow node */
if (befs_bt_read_node(sb, ds, this_node, node_off) != BEFS_OK) {
befs_error(sb, "befs_btree_find() failed to read "
"node at %llu", node_off);
@@ -291,8 +291,7 @@ befs_btree_find(struct super_block *sb, const
befs_data_stream *ds,
}
}
- /* at the correct leaf node now */
-
+ /* at a leaf node now, check if it is correct */
res = befs_find_key(sb, this_node, key, value);
brelse(this_node->bh);
@@ -323,16 +322,12 @@ befs_btree_find(struct super_block *sb, const
befs_data_stream *ds,
* @findkey: Keystring to search for
* @value: If key is found, the value stored with the key is put here
*
- * finds exact match if one exists, and returns BEFS_BT_MATCH
- * If no exact match, finds first key in node that is greater
- * (alphabetically) than the search key and returns BEFS_BT_PARMATCH
- * (for partial match, I guess). Can you think of something better to
- * call it?
- *
- * If no key was a match or greater than the search key, return
- * BEFS_BT_NOT_FOUND.
+ * Finds exact match if one exists, and returns BEFS_BT_MATCH.
+ * If there is no match and node's value array is too small for key, return
+ * BEFS_BT_OVERFLOW.
+ * If no match and node should countain this key, return BEFS_BT_NOT_FOUND.
*
- * Use binary search instead of a linear.
+ * Uses binary search instead of a linear.
*/
static int
befs_find_key(struct super_block *sb, struct befs_btree_node *node,
@@ -355,9 +350,8 @@ befs_find_key(struct super_block *sb, struct
befs_btree_node *node,
eq = befs_compare_strings(thiskey, keylen, findkey, findkey_len);
if (eq < 0) {
- befs_error(sb, "<--- %s %s not found", __func__, findkey);
- befs_debug(sb, "<--- %s ERROR", __func__);
- return BEFS_BT_NOT_FOUND;
+ befs_debug(sb, "<--- node can't contain %s", findkey);
+ return BEFS_BT_OVERFLOW;
}
valarray = befs_bt_valarray(node);
@@ -385,12 +379,12 @@ befs_find_key(struct super_block *sb, struct
befs_btree_node *node,
else
first = mid + 1;
}
- if (eq < 0)
- *value = fs64_to_cpu(sb, valarray[mid + 1]);
- else
- *value = fs64_to_cpu(sb, valarray[mid]);
- befs_debug(sb, "<--- %s found %s at %d", __func__, thiskey, mid);
- return BEFS_BT_PARMATCH;
+
+ /* return an existing value so caller can arrive to a leaf node */
+ *value = fs64_to_cpu(sb, valarray[mid]);
+ befs_error(sb, "<--- %s %s not found", __func__, findkey);
+ befs_debug(sb, "<--- %s ERROR", __func__);
+ return BEFS_BT_NOT_FOUND;
}
/**
--
2.5.1
