/* Execute actor for each item (or unit, depending on @through_units_p),
starting from @coord, right-ward, until either:
- end of the tree is reached
- unformatted node is met
- error occurred
- @actor returns 0 or less
Error code, or last actor return value is returned.
This is used by plugin/dir/hashe_dir.c:reiser4_find_entry() to move through
sequence of entries with identical keys and alikes.
*/
int reiser4_iterate_tree(reiser4_tree * tree /* tree to scan */ ,
coord_t *coord /* coord to start from */ ,
lock_handle * lh /* lock handle to start with and to
* update along the way */ ,
tree_iterate_actor_t actor /* function to call on each
* item/unit */ ,
void *arg /* argument to pass to @actor */ ,
znode_lock_mode mode /* lock mode on scanned nodes */ ,
int through_units_p /* call @actor on each item or on
* each unit */ )
{
int result;
assert("nikita-1143", tree != NULL);
assert("nikita-1145", coord != NULL);
assert("nikita-1146", lh != NULL);
assert("nikita-1147", actor != NULL);
result = zload(coord->node);
coord_clear_iplug(coord);
if (result != 0)
return result;
if (!coord_is_existing_unit(coord)) {
zrelse(coord->node);
return -ENOENT;
}
while ((result = actor(tree, coord, lh, arg)) > 0) {
/* move further */
if ((through_units_p && coord_next_unit(coord)) ||
(!through_units_p && coord_next_item(coord))) {
do {
lock_handle couple;
/* move to the next node */
init_lh(&couple);
result =
reiser4_get_right_neighbor(&couple,
coord->node,
(int)mode,
GN_CAN_USE_UPPER_LEVELS);
zrelse(coord->node);
if (result == 0) {
result = zload(couple.node);
if (result != 0) {
done_lh(&couple);
return result;
}
coord_init_first_unit(coord,
couple.node);
done_lh(lh);
move_lh(lh, &couple);
} else
return result;
} while (node_is_empty(coord->node));
}
assert("nikita-1149", coord_is_existing_unit(coord));
}
zrelse(coord->node);
return result;
}
/**
* reiser4_replace_extent - replace extent and paste 1 or 2 after it
* @un_extent: coordinate of extent to be overwritten
* @lh: need better comment
* @key: need better comment
* @exts_to_add: data prepared for insertion into tree
* @replace: need better comment
* @flags: need better comment
* @return_insert_position: need better comment
*
* Overwrites one extent, pastes 1 or 2 more ones after overwritten one. If
* @return_inserted_position is 1 - @un_extent and @lh are returned set to
* first of newly inserted units, if it is 0 - @un_extent and @lh are returned
* set to extent which was overwritten.
*/
int reiser4_replace_extent(struct replace_handle *h,
int return_inserted_position)
{
int result;
znode *orig_znode;
/*ON_DEBUG(reiser4_extent orig_ext);*/ /* this is for debugging */
assert("vs-990", coord_is_existing_unit(h->coord));
assert("vs-1375", znode_is_write_locked(h->coord->node));
assert("vs-1426", extent_get_width(&h->overwrite) != 0);
assert("vs-1427", extent_get_width(&h->new_extents[0]) != 0);
assert("vs-1427", ergo(h->nr_new_extents == 2,
extent_get_width(&h->new_extents[1]) != 0));
/* compose structure for paste */
init_new_extent(&h->item, &h->new_extents[0], h->nr_new_extents);
coord_dup(&h->coord_after, h->coord);
init_lh(&h->lh_after);
copy_lh(&h->lh_after, h->lh);
reiser4_tap_init(&h->watch, &h->coord_after, &h->lh_after, ZNODE_WRITE_LOCK);
reiser4_tap_monitor(&h->watch);
ON_DEBUG(h->orig_ext = *extent_by_coord(h->coord));
orig_znode = h->coord->node;
#if REISER4_DEBUG
/* make sure that key is set properly */
unit_key_by_coord(h->coord, &h->tmp);
set_key_offset(&h->tmp,
get_key_offset(&h->tmp) +
extent_get_width(&h->overwrite) * current_blocksize);
assert("vs-1080", keyeq(&h->tmp, &h->paste_key));
#endif
/* set insert point after unit to be replaced */
h->coord->between = AFTER_UNIT;
result = insert_into_item(h->coord, return_inserted_position ? h->lh : NULL,
&h->paste_key, &h->item, h->flags);
if (!result) {
/* now we have to replace the unit after which new units were
inserted. Its position is tracked by @watch */
reiser4_extent *ext;
znode *node;
node = h->coord_after.node;
if (node != orig_znode) {
coord_clear_iplug(&h->coord_after);
result = zload(node);
}
if (likely(!result)) {
ext = extent_by_coord(&h->coord_after);
assert("vs-987", znode_is_loaded(node));
assert("vs-988", !memcmp(ext, &h->orig_ext, sizeof(*ext)));
/* overwrite extent unit */
memcpy(ext, &h->overwrite, sizeof(reiser4_extent));
znode_make_dirty(node);
if (node != orig_znode)
zrelse(node);
if (return_inserted_position == 0) {
/* coord and lh are to be set to overwritten
extent */
assert("vs-1662",
WITH_DATA(node, !memcmp(&h->overwrite,
extent_by_coord(
&h->coord_after),
sizeof(reiser4_extent))));
*h->coord = h->coord_after;
done_lh(h->lh);
copy_lh(h->lh, &h->lh_after);
} else {
/* h->coord and h->lh are to be set to first of
inserted units */
assert("vs-1663",
WITH_DATA(h->coord->node,
!memcmp(&h->new_extents[0],
extent_by_coord(h->coord),
sizeof(reiser4_extent))));
assert("vs-1664", h->lh->node == h->coord->node);
}
}
}
reiser4_tap_done(&h->watch);
return result;
}