Implement a more explicit object system

Make every dynamically allocated, opaque data structure inherit from
a common sqfs_object_t structure with common entry points (e.g. destroy).

This removes tons of public API functions and replaces them with a
simple sqfs_destroy instead. If semantics of the (until now implicit)
object system need to be extended, it can be much more conveniantely
done this way.

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

1 files changed, 18 insertions, 13 deletions

diff --git a/lib/sqfs/xattr_reader.c b/lib/sqfs/xattr_reader.c
index d5b003b..97cf821 100644
--- a/lib/sqfs/xattr_reader.c
+++ b/lib/sqfs/xattr_reader.c
@@ -21,6 +21,8 @@
 #include <errno.h>
 
 struct sqfs_xattr_reader_t {
+	sqfs_object_t base;
+
 	sqfs_u64 xattr_start;
 
 	size_t num_id_blocks;
@@ -34,6 +36,20 @@ struct sqfs_xattr_reader_t {
 	sqfs_file_t *file;
 };
 
+static void xattr_reader_destroy(sqfs_object_t *obj)
+{
+	sqfs_xattr_reader_t *xr = (sqfs_xattr_reader_t *)obj;
+
+	if (xr->kvrd != NULL)
+		sqfs_destroy(xr->kvrd);
+
+	if (xr->idrd != NULL)
+		sqfs_destroy(xr->idrd);
+
+	free(xr->id_block_starts);
+	free(xr);
+}
+
 int sqfs_xattr_reader_load_locations(sqfs_xattr_reader_t *xr)
 {
 	sqfs_xattr_id_table_t idtbl;
@@ -242,18 +258,6 @@ int sqfs_xattr_reader_get_desc(sqfs_xattr_reader_t *xr, sqfs_u32 idx,
 	return 0;
 }
 
-void sqfs_xattr_reader_destroy(sqfs_xattr_reader_t *xr)
-{
-	if (xr->kvrd != NULL)
-		sqfs_meta_reader_destroy(xr->kvrd);
-
-	if (xr->idrd != NULL)
-		sqfs_meta_reader_destroy(xr->idrd);
-
-	free(xr->id_block_starts);
-	free(xr);
-}
-
 sqfs_xattr_reader_t *sqfs_xattr_reader_create(sqfs_file_t *file,
 					      sqfs_super_t *super,
 					      sqfs_compressor_t *cmp)
@@ -263,6 +267,7 @@ sqfs_xattr_reader_t *sqfs_xattr_reader_create(sqfs_file_t *file,
 	if (xr == NULL)
 		return NULL;
 
+	((sqfs_object_t *)xr)->destroy = xattr_reader_destroy;
 	xr->file = file;
 	xr->super = super;
 
@@ -286,6 +291,6 @@ sqfs_xattr_reader_t *sqfs_xattr_reader_create(sqfs_file_t *file,
 
 	return xr;
 fail:
-	sqfs_xattr_reader_destroy(xr);
+	sqfs_destroy(xr);
 	return NULL;
 }