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>

3 files changed, 25 insertions, 25 deletions

diff --git a/lib/common/comp_lzo.c b/lib/common/comp_lzo.c
index f371fb6..a0c838a 100644
--- a/lib/common/comp_lzo.c
+++ b/lib/common/comp_lzo.c
@@ -195,7 +195,7 @@ static sqfs_compressor_t *lzo_create_copy(sqfs_compressor_t *cmp)
 	return (sqfs_compressor_t *)lzo;
 }
 
-static void lzo_destroy(sqfs_compressor_t *base)
+static void lzo_destroy(sqfs_object_t *base)
 {
 	free(base);
 }
@@ -247,11 +247,11 @@ sqfs_compressor_t *lzo_compressor_create(const sqfs_compressor_config_t *cfg)
 	lzo->buf_size = scratch_size;
 	lzo->work_size = lzo_algs[cfg->opt.lzo.algorithm].bufsize;
 
-	base->destroy = lzo_destroy;
 	base->do_block = (cfg->flags & SQFS_COMP_FLAG_UNCOMPRESS) ?
 		lzo_uncomp_block : lzo_comp_block;
 	base->write_options = lzo_write_options;
 	base->read_options = lzo_read_options;
 	base->create_copy = lzo_create_copy;
+	((sqfs_object_t *)base)->destroy = lzo_destroy;
 	return base;
 }
diff --git a/lib/common/io_stdin.c b/lib/common/io_stdin.c
index ca6bf49..469e300 100644
--- a/lib/common/io_stdin.c
+++ b/lib/common/io_stdin.c
@@ -21,7 +21,7 @@ typedef struct {
 } sqfs_file_stdinout_t;
 
 
-static void stdinout_destroy(sqfs_file_t *base)
+static void stdinout_destroy(sqfs_object_t *base)
 {
 	free(base);
 }
@@ -159,7 +159,7 @@ sqfs_file_t *sqfs_get_stdin_file(FILE *fp, const sparse_map_t *map,
 	file->map = map;
 	file->fp = fp;
 
-	base->destroy = stdinout_destroy;
+	((sqfs_object_t *)base)->destroy = stdinout_destroy;
 	base->write_at = stdin_write_at;
 	base->get_size = stdinout_get_size;
 	base->truncate = stdinout_truncate;
diff --git a/lib/common/writer.c b/lib/common/writer.c
index 84a40d2..4762b82 100644
--- a/lib/common/writer.c
+++ b/lib/common/writer.c
@@ -90,7 +90,7 @@ int sqfs_writer_init(sqfs_writer_t *sqfs, const sqfs_writer_cfg_t *wrcfg)
 #ifdef WITH_LZO
 	if (cfg.id == SQFS_COMP_LZO) {
 		if (sqfs->cmp != NULL)
-			sqfs->cmp->destroy(sqfs->cmp);
+			sqfs_destroy(sqfs->cmp);
 
 		sqfs->cmp = lzo_compressor_create(&cfg);
 	}
@@ -187,26 +187,26 @@ int sqfs_writer_init(sqfs_writer_t *sqfs, const sqfs_writer_cfg_t *wrcfg)
 
 	return 0;
 fail_dm:
-	sqfs_meta_writer_destroy(sqfs->dm);
+	sqfs_destroy(sqfs->dm);
 fail_im:
-	sqfs_meta_writer_destroy(sqfs->im);
+	sqfs_destroy(sqfs->im);
 fail_xwr:
 	if (sqfs->xwr != NULL)
-		sqfs_xattr_writer_destroy(sqfs->xwr);
+		sqfs_destroy(sqfs->xwr);
 fail_id:
-	sqfs_id_table_destroy(sqfs->idtbl);
+	sqfs_destroy(sqfs->idtbl);
 fail_data:
-	sqfs_block_processor_destroy(sqfs->data);
+	sqfs_destroy(sqfs->data);
 fail_fragtbl:
-	sqfs_frag_table_destroy(sqfs->fragtbl);
+	sqfs_destroy(sqfs->fragtbl);
 fail_blkwr:
-	sqfs_block_writer_destroy(sqfs->blkwr);
+	sqfs_destroy(sqfs->blkwr);
 fail_cmp:
-	sqfs->cmp->destroy(sqfs->cmp);
+	sqfs_destroy(sqfs->cmp);
 fail_fs:
 	fstree_cleanup(&sqfs->fs);
 fail_file:
-	sqfs->outfile->destroy(sqfs->outfile);
+	sqfs_destroy(sqfs->outfile);
 	return -1;
 }
 
@@ -299,16 +299,16 @@ int sqfs_writer_finish(sqfs_writer_t *sqfs, const sqfs_writer_cfg_t *cfg)
 void sqfs_writer_cleanup(sqfs_writer_t *sqfs)
 {
 	if (sqfs->xwr != NULL)
-		sqfs_xattr_writer_destroy(sqfs->xwr);
-
-	sqfs_dir_writer_destroy(sqfs->dirwr);
-	sqfs_meta_writer_destroy(sqfs->dm);
-	sqfs_meta_writer_destroy(sqfs->im);
-	sqfs_id_table_destroy(sqfs->idtbl);
-	sqfs_block_processor_destroy(sqfs->data);
-	sqfs_block_writer_destroy(sqfs->blkwr);
-	sqfs_frag_table_destroy(sqfs->fragtbl);
-	sqfs->cmp->destroy(sqfs->cmp);
+		sqfs_destroy(sqfs->xwr);
+
+	sqfs_destroy(sqfs->dirwr);
+	sqfs_destroy(sqfs->dm);
+	sqfs_destroy(sqfs->im);
+	sqfs_destroy(sqfs->idtbl);
+	sqfs_destroy(sqfs->data);
+	sqfs_destroy(sqfs->blkwr);
+	sqfs_destroy(sqfs->fragtbl);
+	sqfs_destroy(sqfs->cmp);
 	fstree_cleanup(&sqfs->fs);
-	sqfs->outfile->destroy(sqfs->outfile);
+	sqfs_destroy(sqfs->outfile);
 }