diff --git a/src/libostree/ostree-repo-static-delta-core.c b/src/libostree/ostree-repo-static-delta-core.c index 0669f691..d84f0019 100644 --- a/src/libostree/ostree-repo-static-delta-core.c +++ b/src/libostree/ostree-repo-static-delta-core.c @@ -705,6 +705,7 @@ _ostree_delta_get_endianness (GVariant *superblock, { g_autoptr(GVariant) meta_entries = NULL; guint n_parts; guint i; + gboolean is_byteswapped = FALSE; g_variant_get_child (superblock, 6, "@a" OSTREE_STATIC_DELTA_META_ENTRY_FORMAT, &meta_entries); n_parts = g_variant_n_children (meta_entries); @@ -721,15 +722,36 @@ _ostree_delta_get_endianness (GVariant *superblock, total_objects += n_objects; total_size += size; total_usize += usize; + + if (size > usize) + { + double ratio = ((double)size)/((double)usize); + + /* This should really never happen where compressing things makes it more than 50% bigger. + */ + if (ratio > 1.2) + { + is_byteswapped = TRUE; + break; + } + } } - /* If the average object size is greater than 4GiB, let's assume - * we're dealing with opposite endianness. I'm fairly confident - * no one is going to be shipping peta- or exa- byte size ostree - * deltas, period. Past the gigabyte scale you really want - * bittorrent or something. - */ - if ((total_size / total_objects) > G_MAXUINT32) + if (!is_byteswapped) + { + /* If the average object size is greater than 4GiB, let's assume + * we're dealing with opposite endianness. I'm fairly confident + * no one is going to be shipping peta- or exa- byte size ostree + * deltas, period. Past the gigabyte scale you really want + * bittorrent or something. + */ + if ((total_size / total_objects) > G_MAXUINT32) + { + is_byteswapped = TRUE; + } + } + + if (is_byteswapped) { switch (G_BYTE_ORDER) {