diff options
Diffstat (limited to 'lib/util')
| -rw-r--r-- | lib/util/Makemodule.am | 1 | ||||
| -rw-r--r-- | lib/util/file_cmp.c | 41 |
2 files changed, 42 insertions, 0 deletions
diff --git a/lib/util/Makemodule.am b/lib/util/Makemodule.am index b65ebda..830a338 100644 --- a/lib/util/Makemodule.am +++ b/lib/util/Makemodule.am @@ -13,6 +13,7 @@ libutil_a_SOURCES += lib/util/mkdir_p.c libutil_a_SOURCES += lib/util/canonicalize_name.c libutil_a_SOURCES += lib/util/filename_sane.c libutil_a_SOURCES += lib/util/source_date_epoch.c +libutil_a_SOURCES += lib/util/file_cmp.c libutil_a_CFLAGS = $(AM_CFLAGS) libutil_a_CPPFLAGS = $(AM_CPPFLAGS) diff --git a/lib/util/file_cmp.c b/lib/util/file_cmp.c new file mode 100644 index 0000000..2aa0cc2 --- /dev/null +++ b/lib/util/file_cmp.c @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: LGPL-3.0-or-later */ +/* + * file_cmp.c + * + * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at> + */ +#include "config.h" + +#include "util/util.h" +#include "sqfs/io.h" + +#include <string.h> + +int check_file_range_equal(sqfs_file_t *file, void *scratch, size_t scratch_sz, + sqfs_u64 loc_a, sqfs_u64 loc_b, sqfs_u64 size) +{ + sqfs_u8 *ptr_a = scratch, *ptr_b = ptr_a + scratch_sz / 2; + int ret; + + while (size > 0) { + size_t diff = scratch_sz / 2; + diff = (sqfs_u64)diff > size ? size : diff; + + ret = file->read_at(file, loc_a, ptr_a, diff); + if (ret != 0) + return ret; + + ret = file->read_at(file, loc_b, ptr_b, diff); + if (ret != 0) + return ret; + + if (memcmp(ptr_a, ptr_b, diff) != 0) + return 1; + + size -= diff; + loc_a += diff; + loc_b += diff; + } + + return 0; +} |