Implement istream decompression support

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

1 files changed, 59 insertions, 0 deletions

diff --git a/lib/fstream/uncompress/istream_compressor.c b/lib/fstream/uncompress/istream_compressor.c
new file mode 100644
index 0000000..924f309
--- /dev/null
+++ b/lib/fstream/uncompress/istream_compressor.c
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * istream_compressor.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "../internal.h"
+
+static const char *comp_get_filename(istream_t *strm)
+{
+	istream_comp_t *comp = (istream_comp_t *)strm;
+
+	return comp->wrapped->get_filename(comp->wrapped);
+}
+
+static void comp_destroy(sqfs_object_t *obj)
+{
+	istream_comp_t *comp = (istream_comp_t *)obj;
+
+	comp->cleanup(comp);
+	sqfs_destroy(comp->wrapped);
+	free(comp);
+}
+
+istream_t *istream_compressor_create(istream_t *strm, int comp_id)
+{
+	istream_comp_t *comp = NULL;
+	sqfs_object_t *obj;
+	istream_t *base;
+
+	switch (comp_id) {
+	case FSTREAM_COMPRESSOR_GZIP:
+#ifdef WITH_GZIP
+		comp = istream_gzip_create(strm->get_filename(strm));
+#endif
+		break;
+	case FSTREAM_COMPRESSOR_XZ:
+#ifdef WITH_XZ
+		comp = istream_xz_create(strm->get_filename(strm));
+#endif
+		break;
+	default:
+		break;
+	}
+
+	if (comp == NULL)
+		return NULL;
+
+	comp->wrapped = strm;
+
+	base = (istream_t *)comp;
+	base->get_filename = comp_get_filename;
+	base->buffer = comp->uncompressed;
+	base->eof = false;
+
+	obj = (sqfs_object_t *)comp;
+	obj->destroy = comp_destroy;
+	return base;
+}