Add a generic copying mechanism to sqfs_object_t

This patch adds a deep-copy callback to sqfs_object_t and removes the
copying mechanism from sqfs_compressor_t. This is also interesting for
other types.

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

1 files changed, 59 insertions, 0 deletions

diff --git a/lib/sqfs/xattr_writer.c b/lib/sqfs/xattr_writer.c
index 827d0c5..488fd43 100644
--- a/lib/sqfs/xattr_writer.c
+++ b/lib/sqfs/xattr_writer.c
@@ -115,6 +115,64 @@ struct sqfs_xattr_writer_t {
 };
 
 
+static sqfs_object_t *xattr_writer_copy(const sqfs_object_t *obj)
+{
+	const sqfs_xattr_writer_t *xwr = (const sqfs_xattr_writer_t *)obj;
+	kv_block_desc_t *blk, *it, **next;
+	sqfs_xattr_writer_t *copy;
+
+	copy = calloc(1, sizeof(*copy));
+	if (copy == NULL)
+		return NULL;
+
+	memcpy(copy, xwr, sizeof(*xwr));
+
+	if (str_table_copy(&copy->keys, &xwr->keys))
+		goto fail_keys;
+
+	if (str_table_copy(&copy->values, &xwr->values))
+		goto fail_values;
+
+	copy->max_pairs = xwr->num_pairs;
+	copy->num_pairs = xwr->num_pairs;
+
+	copy->kv_pairs = malloc(sizeof(copy->kv_pairs[0]) * xwr->num_pairs);
+	if (copy->kv_pairs == NULL)
+		goto fail_pairs;
+
+	memcpy(copy->kv_pairs, xwr->kv_pairs,
+	       sizeof(copy->kv_pairs[0]) * xwr->num_pairs);
+
+	next = &(copy->kv_blocks);
+
+	for (it = xwr->kv_blocks; it != NULL; it = it->next) {
+		blk = malloc(sizeof(*blk));
+		if (blk == NULL)
+			goto fail_blk;
+
+		memcpy(blk, it, sizeof(*it));
+		blk->next = NULL;
+
+		*next = blk;
+		next = &(blk->next);
+	}
+
+	return (sqfs_object_t *)copy;
+fail_blk:
+	while (copy->kv_blocks != NULL) {
+		blk = copy->kv_blocks;
+		copy->kv_blocks = copy->kv_blocks->next;
+		free(blk);
+	}
+fail_pairs:
+	str_table_cleanup(&copy->values);
+fail_values:
+	str_table_cleanup(&copy->keys);
+fail_keys:
+	free(copy);
+	return NULL;
+}
+
 static void xattr_writer_destroy(sqfs_object_t *obj)
 {
 	sqfs_xattr_writer_t *xwr = (sqfs_xattr_writer_t *)obj;
@@ -148,6 +206,7 @@ sqfs_xattr_writer_t *sqfs_xattr_writer_create(void)
 	if (xwr->kv_pairs == NULL)
 		goto fail_pairs;
 
+	((sqfs_object_t *)xwr)->copy = xattr_writer_copy;
 	((sqfs_object_t *)xwr)->destroy = xattr_writer_destroy;
 	return xwr;
 fail_pairs: