libsqfs: externalize the dir reader state

Instead of holding the state internally, move it outside and let the
user pass it in. This allows processing multiple directories and going
back and forth between them, while also simplifying the dir reader
internals.

The sqfs_dir_reader_get_inode function can also be made more generic
to accept a reference instead of being fully state dependent.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 16 insertions, 8 deletions

diff --git a/lib/common/src/read_tree.c b/lib/common/src/read_tree.c
index 5d089e5..2879ff4 100644
--- a/lib/common/src/read_tree.c
+++ b/lib/common/src/read_tree.c
@@ -63,6 +63,7 @@ static sqfs_tree_node_t *create_node(sqfs_inode_generic_t *inode,
 }
 
 static int fill_dir(sqfs_dir_reader_t *dr, sqfs_tree_node_t *root,
+		    sqfs_dir_reader_state_t *state,
 		    unsigned int flags)
 {
 	sqfs_tree_node_t *n, *prev, **tail;
@@ -73,7 +74,7 @@ static int fill_dir(sqfs_dir_reader_t *dr, sqfs_tree_node_t *root,
 	tail = &root->children;
 
 	for (;;) {
-		err = sqfs_dir_reader_read(dr, &ent);
+		err = sqfs_dir_reader_read(dr, state, &ent);
 		if (err > 0)
 			break;
 		if (err < 0)
@@ -84,7 +85,7 @@ static int fill_dir(sqfs_dir_reader_t *dr, sqfs_tree_node_t *root,
 			continue;
 		}
 
-		err = sqfs_dir_reader_get_inode(dr, &inode);
+		err = sqfs_dir_reader_get_inode(dr, state->ent_ref, &inode);
 		if (err) {
 			free(ent);
 			return err;
@@ -115,13 +116,16 @@ static int fill_dir(sqfs_dir_reader_t *dr, sqfs_tree_node_t *root,
 	while (n != NULL) {
 		if (n->inode->base.type == SQFS_INODE_DIR ||
 		    n->inode->base.type == SQFS_INODE_EXT_DIR) {
+			sqfs_dir_reader_state_t nstate;
+
 			if (!(flags & SQFS_TREE_NO_RECURSE)) {
 				err = sqfs_dir_reader_open_dir(dr, n->inode,
+					       &nstate,
 					       SQFS_DIR_OPEN_NO_DOT_ENTRIES);
 				if (err)
 					return err;
 
-				err = fill_dir(dr, n, flags);
+				err = fill_dir(dr, n, &nstate, flags);
 				if (err)
 					return err;
 			}
@@ -192,13 +196,15 @@ int sqfs_dir_reader_get_full_hierarchy(sqfs_dir_reader_t *rd,
 	inode = NULL;
 
 	while (path != NULL && *path != '\0') {
+		sqfs_dir_reader_state_t state;
+
 		if (*path == '/') {
 			while (*path == '/')
 				++path;
 			continue;
 		}
 
-		ret = sqfs_dir_reader_open_dir(rd, tail->inode,
+		ret = sqfs_dir_reader_open_dir(rd, tail->inode, &state,
 					       SQFS_DIR_OPEN_NO_DOT_ENTRIES);
 		if (ret)
 			goto fail;
@@ -206,7 +212,7 @@ int sqfs_dir_reader_get_full_hierarchy(sqfs_dir_reader_t *rd,
 		ptr = strchrnul(path, '/');
 
 		for (;;) {
-			ret = sqfs_dir_reader_read(rd, &ent);
+			ret = sqfs_dir_reader_read(rd, &state, &ent);
 			if (ret < 0)
 				goto fail;
 			if (ret > 0) {
@@ -221,7 +227,7 @@ int sqfs_dir_reader_get_full_hierarchy(sqfs_dir_reader_t *rd,
 			free(ent);
 		}
 
-		ret = sqfs_dir_reader_get_inode(rd, &inode);
+		ret = sqfs_dir_reader_get_inode(rd, state.ent_ref, &inode);
 		if (ret) {
 			free(ent);
 			goto fail;
@@ -251,12 +257,14 @@ int sqfs_dir_reader_get_full_hierarchy(sqfs_dir_reader_t *rd,
 
 	if (tail->inode->base.type == SQFS_INODE_DIR ||
 	    tail->inode->base.type == SQFS_INODE_EXT_DIR) {
-		ret = sqfs_dir_reader_open_dir(rd, tail->inode,
+		sqfs_dir_reader_state_t state;
+
+		ret = sqfs_dir_reader_open_dir(rd, tail->inode, &state,
 					       SQFS_DIR_OPEN_NO_DOT_ENTRIES);
 		if (ret)
 			goto fail;
 
-		ret = fill_dir(rd, tail, flags);
+		ret = fill_dir(rd, tail, &state, flags);
 		if (ret)
 			goto fail;
 	}