Cleanup pass on the dirtree infrastructure, in preparation for making rm -r

handle infinite depth. Fix docs, tweak dirtree_handle_callback() semantics,
remove dirtree_start() and don't export dirtree_handle_callback(), instead
offer dirtree_flagread(). (dirtree_read() is a wrapper around dirtree_flagread
passing 0 for flags.)

2 files changed, 23 insertions, 23 deletions

diff --git a/lib/dirtree.c b/lib/dirtree.c
index 8b9f2993..cc1ab90c 100644
--- a/lib/dirtree.c
+++ b/lib/dirtree.c
@@ -17,7 +17,7 @@ static int notdotdot(char *name)
 int dirtree_notdotdot(struct dirtree *catch)
 {
   // Should we skip "." and ".."?
-  return notdotdot(catch->name) ? DIRTREE_SAVE|DIRTREE_RECURSE : 0;
+  return notdotdot(catch->name)*(DIRTREE_SAVE|DIRTREE_RECURSE);
 }
 
 // Create a dirtree node from a path, with stat and symlink info.
@@ -96,21 +96,18 @@ int dirtree_parentfd(struct dirtree *node)
   return node->parent ? node->parent->dirfd : AT_FDCWD;
 }
 
-// Handle callback for a node in the tree. Returns saved node(s) or NULL.
-//
-// By default, allocates a tree of struct dirtree, not following symlinks
-// If callback==NULL, or callback always returns 0, allocate tree of struct
-// dirtree and return root of tree.  Otherwise call callback(node) on each
-// hit, free structures after use, and return NULL.
-//
+// Handle callback for a node in the tree. Returns saved node(s) if
+// callback returns DIRTREE_SAVE, otherwise frees consumed nodes and
+// returns NULL. If !callback return top node unchanged.
+// If !new return DIRTREE_ABORTVAL
 
 struct dirtree *dirtree_handle_callback(struct dirtree *new,
           int (*callback)(struct dirtree *node))
 {
   int flags;
 
-  if (!new) return 0;
-  if (!callback) callback = dirtree_notdotdot;
+  if (!new) return DIRTREE_ABORTVAL;
+  if (!callback) return new;
   flags = callback(new);
 
   if (S_ISDIR(new->st.st_mode)) {
@@ -176,19 +173,21 @@ int dirtree_recurse(struct dirtree *node,
   return flags;
 }
 
-// Create dirtree root
-struct dirtree *dirtree_start(char *name, int symfollow)
+// Create dirtree from path, using callback to filter nodes. If !callback
+// return just the top node. Use dirtree_notdotdot callback to allocate a
+// tree of struct dirtree nodes and return pointer to root node for later
+// processing.
+// Returns DIRTREE_ABORTVAL if path didn't exist (use DIRTREE_SHUTUP to handle
+// error message yourself).
+
+struct dirtree *dirtree_flagread(char *path, int flags,
+  int (*callback)(struct dirtree *node))
 {
-  return dirtree_add_node(0, name, DIRTREE_SYMFOLLOW*!!symfollow);
+  return dirtree_handle_callback(dirtree_add_node(0, path, flags), callback);
 }
 
-// Create dirtree from path, using callback to filter nodes.
-// If callback == NULL allocate a tree of struct dirtree nodes and return
-// pointer to root node.
-
+// Common case
 struct dirtree *dirtree_read(char *path, int (*callback)(struct dirtree *node))
 {
-  struct dirtree *root = dirtree_start(path, 0);
-
-  return root ? dirtree_handle_callback(root, callback) : DIRTREE_ABORTVAL;
+  return dirtree_flagread(path, 0, callback);
 }
diff --git a/lib/lib.h b/lib/lib.h
index c8cff6ef..917be0c1 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -62,6 +62,8 @@ void get_optflags(void);
 #define DIRTREE_SYMFOLLOW    8
 // Don't warn about failure to stat
 #define DIRTREE_SHUTUP      16
+// Breadth first traversal, conserves filehandles at the expense of memory
+#define DIRTREE_BREADTH     32
 // Don't look at any more files in this directory.
 #define DIRTREE_ABORT      256
 
@@ -77,15 +79,14 @@ struct dirtree {
   char name[];
 };
 
-struct dirtree *dirtree_start(char *name, int symfollow);
 struct dirtree *dirtree_add_node(struct dirtree *p, char *name, int flags);
 char *dirtree_path(struct dirtree *node, int *plen);
 int dirtree_notdotdot(struct dirtree *catch);
 int dirtree_parentfd(struct dirtree *node);
-struct dirtree *dirtree_handle_callback(struct dirtree *new,
-  int (*callback)(struct dirtree *node));
 int dirtree_recurse(struct dirtree *node, int (*callback)(struct dirtree *node),
   int symfollow);
+struct dirtree *dirtree_flagread(char *path, int flags,
+  int (*callback)(struct dirtree *node));
 struct dirtree *dirtree_read(char *path, int (*callback)(struct dirtree *node));
 
 // help.c