aboutsummaryrefslogtreecommitdiff
path: root/src/liblzma/Makefile.am (follow)
AgeCommit message (Collapse)AuthorFilesLines
2022-12-13Bump version to 5.4.0 and soname to 5.4.0.larhzu/v5.4.0Lasse Collin1-1/+1
2022-09-08liblzma: Vaccinate against an ill patch from RHEL/CentOS 7.Lasse Collin1-3/+7
RHEL/CentOS 7 shipped with 5.1.2alpha, including the threaded encoder that is behind #ifdef LZMA_UNSTABLE in the API headers. In 5.1.2alpha these symbols are under XZ_5.1.2alpha in liblzma.map. API/ABI compatibility tracking isn't done between development releases so newer releases didn't have XZ_5.1.2alpha anymore. Later RHEL/CentOS 7 updated xz to 5.2.2 but they wanted to keep the exported symbols compatible with 5.1.2alpha. After checking the ABI changes it turned out that >= 5.2.0 ABI is backward compatible with the threaded encoder functions from 5.1.2alpha (but not vice versa as fixes and extensions to these functions were made between 5.1.2alpha and 5.2.0). In RHEL/CentOS 7, XZ Utils 5.2.2 was patched with xz-5.2.2-compat-libs.patch to modify liblzma.map: - XZ_5.1.2alpha was added with lzma_stream_encoder_mt and lzma_stream_encoder_mt_memusage. This matched XZ Utils 5.1.2alpha. - XZ_5.2 was replaced with XZ_5.2.2. It is clear that this was an error; the intention was to keep using XZ_5.2 (XZ_5.2.2 has never been used in XZ Utils). So XZ_5.2.2 lists all symbols that were listed under XZ_5.2 before the patch. lzma_stream_encoder_mt and _mt_memusage are included too so they are listed both here and under XZ_5.1.2alpha. The patch didn't add any __asm__(".symver ...") lines to the .c files. Thus the resulting liblzma.so exports the threaded encoder functions under XZ_5.1.2alpha only. Listing the two functions also under XZ_5.2.2 in liblzma.map has no effect without matching .symver lines. The lack of XZ_5.2 in RHEL/CentOS 7 means that binaries linked against unpatched XZ Utils 5.2.x won't run on RHEL/CentOS 7. This is unfortunate but this alone isn't too bad as the problem is contained within RHEL/CentOS 7 and doesn't affect users of other distributions. It could also be fixed internally in RHEL/CentOS 7. The second problem is more serious: In XZ Utils 5.2.2 the API headers don't have #ifdef LZMA_UNSTABLE for obvious reasons. This is true in RHEL/CentOS 7 version too. Thus now programs using new APIs can be compiled without an extra #define. However, the programs end up depending on symbol version XZ_5.1.2alpha (and possibly also XZ_5.2.2) instead of XZ_5.2 as they would with an unpatched XZ Utils 5.2.2. This means that such binaries won't run on other distributions shipping XZ Utils >= 5.2.0 as they don't provide XZ_5.1.2alpha or XZ_5.2.2; they only provide XZ_5.2 (and XZ_5.0). (This includes RHEL/CentOS 8 as the patch luckily isn't included there anymore with XZ Utils 5.2.4.) Binaries built by RHEL/CentOS 7 users get distributed and then people wonder why they don't run on some other distribution. Seems that people have found out about the patch and been copying it to some build scripts, seemingly curing the symptoms but actually spreading the illness further and outside RHEL/CentOS 7. The ill patch seems to be from late 2016 (RHEL 7.3) and in 2017 it had spread at least to EasyBuild. I heard about the events only recently. :-( This commit splits liblzma.map into two versions: one for GNU/Linux and another for other OSes that can use symbol versioning (FreeBSD, Solaris, maybe others). The Linux-specific file and the matching additions to .c files add full compatibility with binaries that have been built against a RHEL/CentOS-patched liblzma. Builds for OSes other than GNU/Linux won't get the vaccine as they should be immune to the problem (I really hope that no build script uses the RHEL/CentOS 7 patch outside GNU/Linux). The RHEL/CentOS compatibility symbols XZ_5.1.2alpha and XZ_5.2.2 are intentionally put *after* XZ_5.2 in liblzma_linux.map. This way if one forgets to #define HAVE_SYMBOL_VERSIONS_LINUX when building, the resulting liblzma.so.5 will have lzma_stream_encoder_mt@@XZ_5.2 since XZ_5.2 {...} is the first one that lists that function. Without HAVE_SYMBOL_VERSIONS_LINUX @XZ_5.1.2alpha and @XZ_5.2.2 will be missing but that's still a minor problem compared to only having lzma_stream_encoder_mt@@XZ_5.1.2alpha! The "local: *;" line was moved to XZ_5.0 so that it doesn't need to be moved around. It doesn't matter where it is put. Having two similar liblzma_*.map files is a bit silly as it is, at least for now, easily possible to generate the generic one from the Linux-specific file. But that adds extra steps and increases the risk of mistakes when supporting more than one build system. So I rather maintain two files in parallel and let validate_map.sh check that they are in sync when "make mydist" is run. This adds .symver lines for lzma_stream_encoder_mt@XZ_5.2.2 and lzma_stream_encoder_mt_memusage@XZ_5.2.2 even though these weren't exported by RHEL/CentOS 7 (only @@XZ_5.1.2alpha was for these two). I added these anyway because someone might misunderstand the RHEL/CentOS 7 patch and think that @XZ_5.2.2 (@@XZ_5.2.2) versions were exported too. At glance one could suggest using __typeof__ to copy the function prototypes when making aliases. However, this doesn't work trivially because __typeof__ won't copy attributes (lzma_nothrow, lzma_pure) and it won't change symbol visibility from hidden to default (done by LZMA_API()). Attributes could be copied with __copy__ attribute but that needs GCC 9 and a fallback method would be needed anyway. This uses __symver__ attribute with GCC >= 10 and __asm__(".symver ...") with everything else. The attribute method is required for LTO (-flto) support with GCC. Using -flto with GCC older than 10 is now broken on GNU/Linux and will not be fixed (can silently result in a broken liblzma build that has dangerously incorrect symbol versions). LTO builds with Clang seem to work with the traditional __asm__(".symver ...") method. Thanks to Boud Roukema for reporting the problem and discussing the details and testing the fix.
2015-03-30Bump version to 5.3.0alpha and soname to 5.3.99.Lasse Collin1-1/+1
The idea of 99 is that it looks a bit weird in this context. For new features there's no API/ABI stability in devel versions.
2015-02-26Bump version and soname for 5.2.1.larhzu/v5.2.1Lasse Collin1-1/+1
2014-12-21Bump version and soname for 5.2.0.Lasse Collin1-1/+1
I know that soname != app version, but I skip AGE=1 in -version-info to make the soname match the liblzma version anyway. It doesn't hurt anything as long as it doesn't conflict with library versioning rules.
2014-10-29Build: Prepare to support Automake's subdir-objects.Lasse Collin1-2/+2
Due to a bug in Automake, subdir-objects won't be enabled for now. http://debbugs.gnu.org/cgi/bugreport.cgi?bug=17354 Thanks to Daniel Richard G. for the original patches.
2014-09-20liblzma: Fix a portability problem in Makefile.am.Lasse Collin1-1/+1
POSIX supports $< only in inference rules (suffix rules). Using it elsewhere is a GNU make extension and doesn't work e.g. with OpenBSD make. Thanks to Christian Weisgerber for the patch.
2014-06-18liblzma: Add lzma_cputhreads().Lasse Collin1-1/+7
2013-09-09Build: Create liblzma.pc in a src/liblzma/Makefile.am.Lasse Collin1-0/+20
Previously it was done in configure, but doing that goes against the Autoconf manual. Autoconf requires that it is possible to override e.g. prefix after running configure and that doesn't work correctly if liblzma.pc is created by configure. A potential downside of this change is that now e.g. libdir in liblzma.pc is a standalone string instead of being defined via ${prefix}, so if one overrides prefix when running pkg-config the libdir won't get the new value. I don't know if this matters in practice. Thanks to Vincent Torri.
2012-07-05Build: Include validate_map.sh in the distribution.Lasse Collin1-1/+1
It's required by "make mydist". Fix also the location of EXTRA_DIST+= so that those files get distributed also if symbol versioning isn't enabled.
2011-05-28liblzma: Use symbol versioning.Lasse Collin1-0/+6
Symbol versioning is enabled by default on GNU/Linux, other GNU-based systems, and FreeBSD. I'm not sure how stable this is, so it may need backward-incompatible changes before the next release. The idea is that alpha and beta symbols are considered unstable and require recompiling the applications that use those symbols. Once a symbol is stable, it may get extended with new features in ways that don't break compatibility with older ABI & API. The mydist target runs validate_map.sh which should catch some probable problems in liblzma.map. Otherwise I would forget to update the map file for new releases.
2011-04-12Bump the version number to 5.1.1alpha and liblzma soname to 5.0.99.larhzu/v5.1.1alphaLasse Collin1-1/+1
2010-10-23Bump version to 5.0.0 and liblzma version-info to 5:0:0.Lasse Collin1-1/+1
2010-05-26Remove the Subblock filter code for now.Lasse Collin1-5/+0
The spec isn't finished and the code didn't compile anymore. It won't be included in XZ Utils 5.0.0. It's easy to get it back once the spec is done.
2009-11-15Add lzma_physmem().Lasse Collin1-2/+3
I had hoped to keep liblzma as purely a compression library as possible (e.g. file I/O will go into a different library), but it seems that applications linking agaisnt liblzma need some way to determine the memory usage limit, and knowing the amount of RAM is one reasonable way to help making such decisions. Thanks to Jonathan Nieder for the original patch.
2009-07-06Use sed instead of $(SED) so that we don't need toLasse Collin1-1/+1
use AC_PROG_SED. We don't do anything fancy with sed, so this should work OK. libtool 2.2 sets SED but 1.5 doesn't, so $(SED) happened to work when using libtool 2.2.
2009-06-30Build system fixesLasse Collin1-17/+62
Don't use libtool convenience libraries to avoid recently discovered long-standing subtle but somewhat severe bugs in libtool (at least 1.5.22 and 2.2.6 are affected). It was found when porting XZ Utils to Windows <http://lists.gnu.org/archive/html/libtool/2009-06/msg00070.html> but the problem is significant also e.g. on GNU/Linux. Unless --disable-shared is passed to configure, static library built from a set of convenience libraries will contain PIC objects. That is, while libtool builds non-PIC objects too, only PIC objects will be used from the convenience libraries. On 32-bit x86 (tested on mobile XP2400+), using PIC instead of non-PIC makes the decompressor 10 % slower with the default CFLAGS. So while xz was linked against static liblzma by default, it got the slower PIC objects unless --disable-shared was used. I tend develop and benchmark with --disable-shared due to faster build time, so I hadn't noticed the problem in benchmarks earlier. This commit also adds support for building Windows resources into liblzma and executables.
2009-06-28Add -no-undefined to get shared liblzma on Windows.Lasse Collin1-1/+1
2009-04-13Put the interesting parts of XZ Utils into the public domain.Lasse Collin1-10/+3
Some minor documentation cleanups were made at the same time.
2008-12-31Updated src/liblzma/Makefile.am to use liblzma.pc.in, whichLasse Collin1-2/+2
should have been in the previous commit.
2008-09-27Some API changes, bug fixes, cleanups etc.Lasse Collin1-1/+1
2008-08-28Sort of garbage collection commit. :-| Many things are stillLasse Collin1-4/+13
broken. API has changed a lot and it will still change a little more here and there. The command line tool doesn't have all the required changes to reflect the API changes, so it's easy to get "internal error" or trigger assertions.
2007-12-09Imported to git.Lasse Collin1-0/+47