4 files changed, 44 insertions, 35 deletions

diff --git a/include/fstree.h b/include/fstree.h
index 6c2ec0b..ea7cf88 100644
--- a/include/fstree.h
+++ b/include/fstree.h
@@ -265,4 +265,7 @@ tree_node_t *tree_node_list_sort(tree_node_t *head);
 /* ASCIIbetically sort all sub directories recursively */
 void tree_node_sort_recursive(tree_node_t *root);
 
+/* resolve a path to a tree node. Returns NULL on failure and sets errno */
+tree_node_t *fstree_node_from_path(fstree_t *fs, const char *path);
+
 #endif /* FSTREE_H */
diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index 6418568..23ce70d 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -3,7 +3,7 @@ libfstree_a_SOURCES += lib/fstree/fstree_sort.c lib/fstree/fstree_from_dir.c
 libfstree_a_SOURCES += lib/fstree/gen_inode_table.c lib/fstree/get_path.c
 libfstree_a_SOURCES += lib/fstree/node_stat.c lib/fstree/mknode.c
 libfstree_a_SOURCES += lib/fstree/add_by_path.c lib/fstree/xattr.c
-libfstree_a_SOURCES += include/fstree.h
+libfstree_a_SOURCES += lib/fstree/node_from_path.c include/fstree.h
 libfstree_a_CFLAGS = $(AM_CFLAGS)
 libfstree_a_CPPFLAGS = $(AM_CPPFLAGS)
 
diff --git a/lib/fstree/node_from_path.c b/lib/fstree/node_from_path.c
new file mode 100644
index 0000000..e617059
--- /dev/null
+++ b/lib/fstree/node_from_path.c
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+#include "fstree.h"
+
+#include <string.h>
+#include <errno.h>
+
+tree_node_t *fstree_node_from_path(fstree_t *fs, const char *path)
+{
+	tree_node_t *n = fs->root;
+	const char *end;
+	size_t len;
+
+	while (path != NULL && *path != '\0') {
+		if (!S_ISDIR(n->mode)) {
+			errno = ENOTDIR;
+			return NULL;
+		}
+
+		end = strchrnul(path, '/');
+		len = end - path;
+
+		for (n = n->data.dir->children; n != NULL; n = n->next) {
+			if (strncmp(path, n->name, len) != 0)
+				continue;
+			if (n->name[len] != '\0')
+				continue;
+			break;
+		}
+
+		if (n == NULL) {
+			errno = ENOENT;
+			return NULL;
+		}
+
+		path = *end ? (end + 1) : end;
+	}
+
+	return n;
+}
diff --git a/unpack/rdsquashfs.c b/unpack/rdsquashfs.c
index 42bddff..4a0f12b 100644
--- a/unpack/rdsquashfs.c
+++ b/unpack/rdsquashfs.c
@@ -1,39 +1,6 @@
 /* SPDX-License-Identifier: GPL-3.0-or-later */
 #include "rdsquashfs.h"
 
-static tree_node_t *find_node(tree_node_t *n, const char *path)
-{
-	const char *end;
-	size_t len;
-
-	while (path != NULL && *path != '\0') {
-		if (!S_ISDIR(n->mode)) {
-			errno = ENOTDIR;
-			return NULL;
-		}
-
-		end = strchrnul(path, '/');
-		len = end - path;
-
-		for (n = n->data.dir->children; n != NULL; n = n->next) {
-			if (strncmp(path, n->name, len) != 0)
-				continue;
-			if (n->name[len] != '\0')
-				continue;
-			break;
-		}
-
-		if (n == NULL) {
-			errno = ENOENT;
-			return NULL;
-		}
-
-		path = *end ? (end + 1) : end;
-	}
-
-	return n;
-}
-
 int main(int argc, char **argv)
 {
 	int status = EXIT_FAILURE;
@@ -76,7 +43,7 @@ int main(int argc, char **argv)
 		goto out_cmp;
 
 	if (opt.cmdpath != NULL) {
-		n = find_node(fs.root, opt.cmdpath);
+		n = fstree_node_from_path(&fs, opt.cmdpath);
 		if (n == NULL) {
 			perror(opt.cmdpath);
 			goto out_fs;