From 6d5c85576cb7ed198952f79fc908b10d775170fe Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Wed, 2 Oct 2024 00:04:01 +0200 Subject: [PATCH 4/4] reflink: add unit tests Add two tests for the --reflink option. reflink.at: - creates an archive with --reflink, with member sizes and a deep member name chosen to exercise the pad record sizing - checks that the archive contains one comment pad record per non-empty regular member - extracts the archive with --reflink and verifies the contents byte for byte, also to stdout and from a non-aligned archive, which must fall back to a regular copy reflink01.at: - on a filesystem supporting copy-on-write clones, verifies with filefrag that the extracted members really share extents with the archive; skipped elsewhere - with a small record size, verifies that the last member, whose rounded-up range would poke past the archive end, is cloned up to the archive EOF and still shares its extents * tests/reflink.at: New file. * tests/reflink01.at: New file. * tests/Makefile.am (TESTSUITE_AT): Add them. * tests/testsuite.at: Include them. --- tests/Makefile.am | 2 ++ tests/reflink.at | 80 ++++++++++++++++++++++++++++++++++++++++++++++ tests/reflink01.at | 73 ++++++++++++++++++++++++++++++++++++++++++ tests/testsuite.at | 4 +++ 4 files changed, 159 insertions(+) create mode 100644 tests/reflink.at create mode 100644 tests/reflink01.at diff --git a/tests/Makefile.am b/tests/Makefile.am index 4f666b09..843c6fbd 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -216,6 +216,8 @@ TESTSUITE_AT = \ positional03.at\ recurs02.at\ recurse.at\ + reflink.at\ + reflink01.at\ remfiles01.at\ remfiles02.at\ remfiles03.at\ diff --git a/tests/reflink.at b/tests/reflink.at new file mode 100644 index 00000000..e21b67b2 --- /dev/null +++ b/tests/reflink.at @@ -0,0 +1,80 @@ +# Process this file with autom4te to create testsuite. -*- Autotest -*- +# Test suite for GNU tar. +# Copyright 2013-2025 Free Software Foundation, Inc. +# +# GNU tar is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# GNU tar is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# Description: ensure tar can create archives with the data alignment +# padding used by reflinks, due option --reflink, and extract them +# correctly both with and without reflinks. +# + +AT_SETUP([reflink archive]) +AT_KEYWORDS([create extract reflink archive]) + +AT_TAR_CHECK([ +mkdir dir +: > dir/0k +genfile --length 1 --file dir/1b +genfile --length 3070 --file dir/3k +genfile --length 4096 --file dir/4k +genfile --length 5000 --file dir/5k +genfile --length 9216 --file dir/9k + +# A deep member name grows the extended header past the size of the +# pad record, exercising the comment sizing logic. +d=@S|@(awk 'BEGIN { s = "dir" + for (i = 0; i < 50; i++) + s = s "/looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong" i + print s }') +mkdir -p @S|@d || exit 77 +genfile --length 2000 --file @S|@d/deep + +tar -cf foo.tar --reflink --sort=name dir + +# each non-empty regular member carries a comment pad record +LC_ALL=C tr -c '@<:@:print:@:>@' '@<:@\n*@:>@' < foo.tar | + LC_ALL=C grep -c ' comment=' + +# extract using reflinks and verify contents +mkdir out +(cd out && tar -xf ../foo.tar --reflink) +cmp dir/1b out/dir/1b +cmp dir/3k out/dir/3k +cmp dir/4k out/dir/4k +cmp dir/5k out/dir/5k +cmp dir/9k out/dir/9k +cmp @S|@d/deep out/@S|@d/deep +echo reflink-ok + +# extraction to stdout must not use reflinks +tar -xOf foo.tar --reflink dir/3k dir/5k > cat.out +cat dir/3k dir/5k | cmp - cat.out +echo stdout-ok + +# extracting a non-aligned archive falls back to a regular copy +tar -cf plain.tar dir +mkdir out2 +(cd out2 && tar -xf ../plain.tar --reflink) +cmp dir/9k out2/dir/9k +echo fallback-ok +], +[0], +[6 +reflink-ok +stdout-ok +fallback-ok +],[],[],[],[pax]) + +AT_CLEANUP diff --git a/tests/reflink01.at b/tests/reflink01.at new file mode 100644 index 00000000..68735d1e --- /dev/null +++ b/tests/reflink01.at @@ -0,0 +1,73 @@ +# Process this file with autom4te to create testsuite. -*- Autotest -*- +# Test suite for GNU tar. +# Copyright 2013-2025 Free Software Foundation, Inc. +# +# GNU tar is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# GNU tar is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# Description: on a filesystem supporting copy-on-write clones, ensure +# that extracting with --reflink really shares blocks with the archive +# instead of silently falling back to a copy. This catches alignment +# regressions on the create side, which would otherwise only show up +# as a performance loss. The test is skipped when the filesystem or +# the required tools do not support reflinks. +# + +AT_SETUP([reflink clone sharing]) +AT_KEYWORDS([create extract reflink reflink01]) + +AT_TAR_CHECK([ +# require a filesystem with working reflinks and a filefrag that +# reports shared extents +genfile --length 100000 --file probe.src +cp --reflink=always probe.src probe 2>/dev/null || exit 77 +sync +filefrag -v probe 2>/dev/null | grep -qi shared || exit 77 + +mkdir dir +genfile --length 50000 --file dir/a +genfile --length 4096 --file dir/b +genfile --length 5001 --file dir/c + +tar -cf foo.tar --reflink --sort=name dir + +mkdir out +(cd out && tar -xf ../foo.tar --reflink) +cmp dir/a out/dir/a +cmp dir/b out/dir/b +cmp dir/c out/dir/c + +# every extracted member must share extents with the archive +sync +filefrag -v out/dir/a | grep -qi shared || echo a not shared +filefrag -v out/dir/b | grep -qi shared || echo b not shared +filefrag -v out/dir/c | grep -qi shared || echo c not shared +echo shared-ok + +# with a small record size the rounded-up range of the last member +# pokes past the end of the archive: it must be cloned up to the +# archive EOF and still share its extents +tar -cf small.tar --reflink --sort=name -b 1 dir +mkdir out2 +(cd out2 && tar -xf ../small.tar --reflink) +cmp dir/c out2/dir/c +sync +filefrag -v out2/dir/c | grep -qi shared || echo tail not shared +echo eof-clone-ok +], +[0], +[shared-ok +eof-clone-ok +],[],[],[],[pax]) + +AT_CLEANUP diff --git a/tests/testsuite.at b/tests/testsuite.at index ab30c2ab..2df1aeea 100644 --- a/tests/testsuite.at +++ b/tests/testsuite.at @@ -548,3 +548,7 @@ m4_include([star/ustar-big-2g.at]) m4_include([star/ustar-big-8g.at]) m4_include([star/pax-big-10g.at]) + +AT_BANNER([Reflinks]) +m4_include([reflink.at]) +m4_include([reflink01.at]) -- 2.50.1