Factor out dirtree_comeagain() callback, setting up depth-first search with open filehandle in node->extra.

3 files changed, 23 insertions, 12 deletions

diff --git a/lib/dirtree.c b/lib/dirtree.c
index 418e8eb1..01e0ea8c 100644
--- a/lib/dirtree.c
+++ b/lib/dirtree.c
@@ -78,6 +78,23 @@ int dirtree_notdotdot(struct dirtree *catch)
 	return DIRTREE_SAVE|DIRTREE_RECURSE;
 }
 
+// depth first recursion
+int dirtree_comeagain(struct dirtree *try, int recurse)
+{
+	int ret = dirtree_notdotdot(try);
+	if (ret) {
+		if (S_ISDIR(try->st.st_mode)) {
+			if (!try->extra) {
+				try->extra = xdup(try->data);
+				if (recurse) return DIRTREE_COMEAGAIN;
+			}
+		} else try->extra = openat(try->parent ? try->parent->data : AT_FDCWD,
+			try->name, 0);
+	}
+
+	return ret;
+}
+
 // 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
diff --git a/lib/lib.h b/lib/lib.h
index 5a184ccf..88810b1f 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -74,6 +74,7 @@ struct dirtree {
 struct dirtree *dirtree_add_node(int dirfd, char *name);
 char *dirtree_path(struct dirtree *node, int *plen);
 int dirtree_notdotdot(struct dirtree *catch);
+int dirtree_comeagain(struct dirtree *try, int recurse);
 struct dirtree *handle_callback(struct dirtree *new,
 	int (*callback)(struct dirtree *node));
 void dirtree_recurse(struct dirtree *node,
diff --git a/toys/chgrp.c b/toys/chgrp.c
index 5cf43896..935e1781 100644
--- a/toys/chgrp.c
+++ b/toys/chgrp.c
@@ -40,19 +40,12 @@ DEFINE_GLOBALS(
 
 static int do_chgrp(struct dirtree *node)
 {
-	int fd, ret = 1, flags = toys.optflags;
+	int ret, flags = toys.optflags;
 
-	if (!dirtree_notdotdot(node)) return 0;
+	ret = dirtree_comeagain(node, flags & FLAG_R);
+	if (!ret || ret == DIRTREE_COMEAGAIN) return ret;
 
-	// Handle recursion, and make it depth first
-	if (S_ISDIR(node->st.st_mode)) {
-		if (!node->extra) node->extra = dup(node->data);
-		if ((flags & FLAG_R) && node->data != -1) return DIRTREE_COMEAGAIN;
-		fd = node->extra;
-	} else fd = openat(node->parent ? node->parent->data : AT_FDCWD,
-		node->name, 0);
-
-	if (fd != -1) ret = fchown(fd, -1, TT.group);
+	if (node->extra != -1) ret = fchown(node->extra, -1, TT.group);
 
 	if (ret || (flags & FLAG_v)) {
 		char *path = dirtree_path(node, 0);
@@ -62,7 +55,7 @@ static int do_chgrp(struct dirtree *node)
 			perror_msg("changing group of '%s' to '%s'", path, TT.group_name);
 		free(path);
 	}
-	close(fd);
+	close(node->extra);
 	toys.exitval |= ret;
 
 	return 0;