From: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
Given a 'struct cache_tree', it may be beneficial to navigate directly
to a node within that corresponds to a given path name. Create
cache_tree_find_path() for this function. It returns NULL when no such
path exists.
The implementation is adapted from do_invalidate_path() which does a
similar search but also modifies the nodes it finds along the way. The
method could be implemented simply using tail-recursion, but this while
loop does the same thing.
This new method is not currently used, but will be in an upcoming
change.
Helped-by: Junio C Hamano <gitster@xxxxxxxxx>
Signed-off-by: Derrick Stolee <derrickstolee@xxxxxxxxxx>
---
cache-tree.c | 27 +++++++++++++++++++++++++++
cache-tree.h | 2 ++
2 files changed, 29 insertions(+)
diff --git a/cache-tree.c b/cache-tree.c
index 6752f69d515..f42db920d10 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -100,6 +100,33 @@ struct cache_tree_sub *cache_tree_sub(struct cache_tree *it, const char *path)
return find_subtree(it, path, pathlen, 1);
}
+struct cache_tree *cache_tree_find_path(struct cache_tree *it, const char *path)
+{
+ const char *slash;
+ int namelen;
+ struct cache_tree_sub it_sub = {
+ .cache_tree = it,
+ };
+ struct cache_tree_sub *down = &it_sub;
+
+ while (down) {
+ slash = strchrnul(path, '/');
+ namelen = slash - path;
+ down->cache_tree->entry_count = -1;
+ if (!*slash) {
+ int pos;
+ pos = cache_tree_subtree_pos(down->cache_tree, path, namelen);
+ if (0 <= pos)
+ return down->cache_tree->down[pos]->cache_tree;
+ return NULL;
+ }
+ down = find_subtree(it, path, namelen, 0);
+ path = slash + 1;
+ }
+
+ return NULL;
+}
+
static int do_invalidate_path(struct cache_tree *it, const char *path)
{
/* a/b/c
diff --git a/cache-tree.h b/cache-tree.h
index 8efeccebfc9..f75f8e74dcd 100644
--- a/cache-tree.h
+++ b/cache-tree.h
@@ -29,6 +29,8 @@ struct cache_tree_sub *cache_tree_sub(struct cache_tree *, const char *);
int cache_tree_subtree_pos(struct cache_tree *it, const char *path, int pathlen);
+struct cache_tree *cache_tree_find_path(struct cache_tree *it, const char *path);
+
void cache_tree_write(struct strbuf *, struct cache_tree *root);
struct cache_tree *cache_tree_read(const char *buffer, unsigned long size);
--
gitgitgadget
