Commit Graph

1158 Commits

Author SHA1 Message Date
Jia Tan d4f4a4d040 xz: Detect when all data will be written to standard out earlier.
If the -c, --stdout argument is not used, then we can still detect when
the data will be written to standard out if all of the provided
filenames are "-" (denoting standard in) or if no filenames are
provided.
2023-11-14 20:27:04 +08:00
Jia Tan 2ade7246e7 liblzma: Add missing comments to lz_encoder.h. 2023-11-09 01:21:53 +08:00
Lasse Collin 46007049cd liblzma: Fix compilation of fastpos_tablegen.c.
The macro lzma_attr_visibility_hidden has to be defined to make
fastpos.h usable. The visibility attribute is irrelevant to
fastpos_tablegen.c so simply #define the macro to an empty value.

fastpos_tablegen.c is never built by the included build systems
and so the problem wasn't noticed earlier. It's just a standalone
program for generating fastpos_table.c.

Fixes: https://github.com/tukaani-project/xz/pull/69
Thanks to GitHub user Jamaika1.
2023-10-31 21:41:09 +02:00
Lasse Collin 8c36ab79cb liblzma: Add a note why crc_always_inline exists for now.
Solaris Studio is a possible example (not tested) which
supports the always_inline attribute but might not get
detected by the common.h #ifdefs.
2023-10-30 18:44:32 +02:00
Lasse Collin e7a86b94cd liblzma: Use lzma_always_inline in memcmplen.h. 2023-10-30 18:44:32 +02:00
Lasse Collin dcfe563299 liblzma: #define lzma_always_inline in common.h. 2023-10-30 18:44:32 +02:00
Lasse Collin 41113fe30a liblzma: Use lzma_attr_visibility_hidden on private extern declarations.
These variables are internal to liblzma and not exposed in the API.
2023-10-30 18:06:25 +02:00
Lasse Collin a2f5ca706a liblzma: #define lzma_attr_visibility_hidden in common.h.
In ELF shared libs:

-fvisibility=hidden affects definitions of symbols but not
declarations.[*] This doesn't affect direct calls to functions
inside liblzma as a linker can replace a call to lzma_foo@plt
with a call directly to lzma_foo when -fvisibility=hidden is used.

[*] It has to be like this because otherwise every installed
    header file would need to explictly set the symbol visibility
    to default.

When accessing extern variables that aren't defined in the
same translation unit, compiler assumes that the variable has
the default visibility and thus indirection is needed. Unlike
function calls, linker cannot optimize this.

Using __attribute__((__visibility__("hidden"))) with the extern
variable declarations tells the compiler that indirection isn't
needed because the definition is in the same shared library.

About 15+ years ago, someone told me that it would be good if
the CRC tables would be defined in the same translation unit
as the C code of the CRC functions. While I understood that it
could help a tiny amount, I didn't want to change the code because
a separate translation unit for the CRC tables was needed for the
x86 assembly code anyway. But when visibility attributes are
supported, simply marking the extern declaration with the
hidden attribute will get identical result. When there are only
a few affected variables, this is trivial to do. I wish I had
understood this back then already.
2023-10-30 18:03:39 +02:00
Lasse Collin 2c7ee92e44 liblzma: Refer to MinGW-w64 instead of MinGW in the API headers.
MinGW (formely a MinGW.org Project, later the MinGW.OSDN Project
at <https://osdn.net/projects/mingw/>) has GCC 9.2.0 as the
most recent GCC package (released 2021-02-02). The project might
still be alive but majority of people have switched to MinGW-w64.
Thus it seems clearer to refer to MinGW-w64 in our API headers too.
Building with MinGW is likely to still work but I haven't tested it
in the recent years.
2023-10-26 21:46:06 +03:00
Lasse Collin a7d1b2825c liblzma: Add Cflags.private to liblzma.pc.in for MSYS2.
It properly adds -DLZMA_API_STATIC when compiling code that
will be linked against static liblzma. Having it there on
systems other than Windows does no harm.

See: https://www.msys2.org/docs/pkgconfig/
2023-10-26 21:46:06 +03:00
Lasse Collin 8276c7f41c xz: Support basic sandboxing with Linux Landlock (ABI versions 1-3).
It is enabled only when decompressing one file to stdout,
similar to how Capsicum is used.

Landlock was added in Linux 5.13.
2023-10-22 19:03:52 +03:00
Lasse Collin 2e2cd11535 Simplify detection of Capsicum support.
This removes support for FreeBSD 10.0 and 10.1 which used
<sys/capability.h> instead of <sys/capsicum.h>. Support for
FreeBSD 10.1 ended on 2016-12-31. So now FreeBSD >= 10.2 is
required to enable Capsicum support.

This also removes support for Capsicum on Linux (libcaprights)
which seems to have been unmaintained since 2017 and Linux 4.11:
https://github.com/google/capsicum-linux
2023-10-22 19:03:52 +03:00
Lasse Collin c57858b60e xz/Windows: Allow clock_gettime with POSIX threads.
If winpthreads are used for threading, it's OK to use clock_gettime()
from winpthreads too.
2023-10-22 18:59:45 +03:00
Lasse Collin dd32f628bb mythread.h: Make MYTHREAD_POSIX compatible with MinGW-w64's winpthreads.
This might be almost useless but it doesn't need much extra code either.
2023-10-22 18:59:45 +03:00
Lasse Collin 46fd991cd2 xz/Windows: Ensure that clock_gettime() isn't used with MinGW-w64.
This commit alone doesn't change anything in the real-world:

  - configure.ac currently checks for clock_gettime() only
    when using pthreads.

  - CMakeLists.txt doesn't check for clock_gettime() on Windows.

So clock_gettime() wasn't used with MinGW-w64 before either.

clock_gettime() provides monotonic time and it's better than
gettimeofday() in this sense. But clock_gettime() is defined
in winpthreads, and liblzma or xz needs nothing else from
winpthreads. By avoiding clock_gettime(), we avoid the dependency on
libwinpthread-1.dll or the need to link against the static version.

As a bonus, GetTickCount64() and MinGW-w64's gettimeofday() can be
faster than clock_gettime(CLOCK_MONOTONIC, &tv). The resolution
is more than good enough for the progress indicator in xz.
2023-10-22 18:59:45 +03:00
Lasse Collin cdb4d91f24 xz/Windows: Use GetTickCount64() with MinGW-w64 if using Vista threads. 2023-10-22 18:59:45 +03:00
Jia Tan 988e09f27b liblzma: Move is_clmul_supported() back to crc_common.h.
This partially reverts creating crc_clmul.c
(8c0f9376f5) where is_clmul_supported()
was moved, extern'ed, and renamed to lzma_is_clmul_supported(). This
caused a problem when the function call to lzma_is_clmul_supported()
results in a call through the PLT. ifunc resolvers run very early in
the dynamic loading sequence, so the PLT may not be setup properly at
this point. Whether the PLT is used or not for
lzma_is_clmul_supported() depened upon the compiler-toolchain used and
flags.

In liblzma compiled with GCC, for instance, GCC will go through the PLT
for function calls internal to liblzma if the version scripts and
symbol visibility hiding are not used. If lazy-binding is disabled,
then it would have made any program linked with liblzma fail during
dynamic loading in the ifunc resolver.
2023-10-21 00:01:29 +08:00
Jia Tan 105c7ca90d Build: Remove check for COND_CHECK_CRC32 in check/Makefile.inc.
Currently crc32 is always enabled, so COND_CHECK_CRC32 must always be
set. Because of this, it makes the recent change to conditionally
compile check/crc_clmul.c appear wrong since that file has CLMUL
implementations for both CRC32 and CRC64.
2023-10-19 16:23:32 +08:00
Jia Tan c60b25569d liblzma: Fix -fsanitize=address failure with crc_clmul functions.
After forcing crc_simd_body() to always be inlined it caused
-fsanitize=address to fail for lzma_crc32_clmul() and
lzma_crc64_clmul(). The __no_sanitize_address__ attribute was added
to lzma_crc32_clmul() and lzma_crc64_clmul(), but not removed from
crc_simd_body(). ASAN and inline functions behavior has changed over
the years for GCC specifically, so while strictly required we will
keep __attribute__((__no_sanitize_address__)) on crc_simd_body() in
case this becomes a requirement in the future.

Older GCC versions refuse to inline a function with ASAN if the
caller and callee do not agree on sanitization flags
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89124#c3). If the
function was forced to be inlined, it will not compile if the callee
function has __no_sanitize_address__ but the caller doesn't.
2023-10-19 01:15:20 +08:00
Lasse Collin c8f715f1bc tuklib_integer: Revise unaligned reads and writes on strict-align archs.
In XZ Utils context this doesn't matter much because
unaligned reads and writes aren't used in hot code
when TUKLIB_FAST_UNALIGNED_ACCESS isn't #defined.
2023-10-18 19:02:45 +03:00
Lasse Collin 6828242735 tuklib_integer: Add missing write64be and write64le fallback functions. 2023-10-18 19:02:45 +03:00
Jia Tan 1c8884f0af liblzma: Set the MSVC optimization fix to only cover lzma_crc64_clmul().
After testing a 32-bit Release build on MSVC, only lzma_crc64_clmul()
has the bug. crc_simd_body() and lzma_crc32_clmul() do not need the
optimizations disabled.
2023-10-18 23:54:41 +08:00
Lasse Collin 5ce0f7a48b liblzma: CRC_USE_GENERIC_FOR_SMALL_INPUTS cannot be used with ifunc. 2023-10-18 23:54:41 +08:00
Lasse Collin 2773538049 liblzma: Include common.h in crc_common.h.
crc_common.h depends on common.h. The headers include common.h except
when there is a reason to not do so.
2023-10-18 23:54:41 +08:00
Jia Tan e13b7947b9 liblzma: Add include guards to crc_common.h. 2023-10-18 23:54:41 +08:00
Jia Tan 40abd88afc liblzma: Add the crc_always_inline macro to crc_simd_body().
Forcing this to be inline has a significant speed improvement at the
cost of a few repeated instructions. The compilers tested on did not
inline this function since it is large and is used twice in the same
translation unit.
2023-10-18 23:54:41 +08:00
Jia Tan a5966c276b liblzma: Create crc_always_inline macro.
This macro must be used instead of the inline keyword. On MSVC, it is
a replacement for __forceinline which is an MSVC specific keyword that
should not be used with inline (it will issue a warning if it is).

It does not use a build system check to determine if
__attribute__((__always_inline__)) since all compilers that can use
CLMUL extensions (except the special case for MSVC) should support this
attribute. If this assumption is incorrect then it will result in a bug
report instead of silently producing slow code.
2023-10-18 23:54:41 +08:00
Jia Tan 96b663f67c liblzma: Refactor CRC comments.
A detailed description of the three dispatch methods was added. Also,
duplicated comments now only appear in crc32_fast.c or were removed from
both crc32_fast.c and crc64_fast.c if they appeared in crc_clmul.c.
2023-10-18 23:54:41 +08:00
Jia Tan 8c0f9376f5 liblzma: Create crc_clmul.c.
Both crc32_clmul() and crc64_clmul() are now exported from
crc32_clmul.c as lzma_crc32_clmul() and lzma_crc64_clmul(). This
ensures that is_clmul_supported() (now lzma_is_clmul_supported()) is
not duplicated between crc32_fast.c and crc64_fast.c.

Also, it encapsulates the complexity of the CLMUL implementations into a
single file and reduces the complexity of crc32_fast.c and crc64_fast.c.
Before, CLMUL code was present in crc32_fast.c, crc64_fast.c, and
crc_common.h.

During the conversion, various cleanups were applied to code (thanks to
Lasse Collin) including:

- Require using semicolons with MASK_/L/H/LH macros.
- Variable typing and const handling improvements.
- Improvements to comments.
- Fixes to the pragmas used.
- Removed unneeded variables.
- Whitespace improvements.
- Fixed CRC_USE_GENERIC_FOR_SMALL_INPUTS handling.
- Silenced warnings and removed the need for some #pragmas
2023-10-18 23:54:36 +08:00
Jia Tan a3ebc2c516 liblzma: Define CRC_USE_IFUNC in crc_common.h.
When ifunc is supported, we can define a simpler macro instead of
repeating the more complex check in both crc32_fast.c and crc64_fast.c.
2023-10-18 20:41:11 +08:00
Hans Jansen f1cd9d7194 liblzma: Added crc32_clmul to crc32_fast.c. 2023-10-13 20:54:05 +08:00
Hans Jansen 93e6fb08b2 liblzma: Moved CLMUL CRC logic to crc_common.h.
crc64_fast.c was updated to use the code from crc_common.h instead.
2023-10-13 20:54:05 +08:00
Hans Jansen 233885a437 liblzma: Rename crc_macros.h to crc_common.h. 2023-10-13 20:54:05 +08:00
Lasse Collin 5a9af95f85 liblzma: Update a comment.
The C standards don't allow an empty translation unit which can be
avoided by declaring something, without exporting any symbols.

When I committed f644473a21 I had
a feeling that some specific toolchain somewhere didn't like
empty object files (assembler or maybe "ar" complained) but
I cannot find anything to confirm this now. Quite likely I
remembered nonsense. I leave this here as a note to my future self. :-)
2023-09-26 21:47:13 +03:00
Jia Tan 8ebaf3f665 liblzma: Avoid compiler warning without creating extra symbol.
When the generic fast crc64 method is used, then we omit
lzma_crc64_table[][]. Similar to
d9166b52cf, we can avoid compiler warnings
with -Wempty-translation-unit (Clang) or -pedantic (GCC) by creating a
never used typedef instead of an extra symbol.
2023-09-27 00:04:40 +08:00
Jia Tan 9fb5de41f2 Scripts: Change quoting style from `...' to '...'. 2023-09-24 22:10:41 +08:00
Jia Tan eaebdef4d4 xz: Change quoting style from `...' to '...'. 2023-09-24 22:10:18 +08:00
Jia Tan f6667702bf liblzma: Change quoting style from `...' to '...'.
This was done for both internal and API headers.
2023-09-24 22:09:47 +08:00
Lasse Collin e582f8e0fe tuklib_physmem: Comment out support for Windows versions older than 2000. 2023-09-24 17:48:13 +03:00
Lasse Collin 7d73d1f0e0 sysdefs.h: Update the comment about __USE_MINGW_ANSI_STDIO. 2023-09-24 16:32:32 +03:00
Lasse Collin 2a9929af0a xz: Windows: Don't (de)compress to special files like "con" or "nul".
Before this commit, the following writes "foo" to the
console and deletes the input file:

    echo foo | xz > con_xz
    xz --suffix=_xz --decompress con_xz

It cannot happen without --suffix because names like con.xz
are also special and so attempting to decompress con.xz
(or compress con to con.xz) will already fail when opening
the input file.

Similar thing is possible when compressing. The following
writes to "nul" and the input file "n" is deleted.

    echo foo | xz > n
    xz --suffix=ul n

Now xz checks if the destination is a special file before
continuing. DOS/DJGPP version had a check for this but
Windows (and OS/2) didn't.
2023-09-22 20:16:40 +03:00
Lasse Collin 8c2d197c94 MSVC: #define inline and restrict only when needed.
This also drops the check for _WIN32 as that shouldn't be needed.
2023-09-22 20:06:27 +03:00
Lasse Collin ee7709bae5 liblzma: Move a few __attribute__ uses in function declarations.
The API headers have many attributes but these were left
as is for now.
2023-09-22 20:06:27 +03:00
Lasse Collin 217958d887 xz, xzdec, lzmainfo: Use tuklib_attr_noreturn.
For compatibility with C23's [[noreturn]], tuklib_attr_noreturn
must be at the beginning of declaration (before "extern" or
"static", and even before any GNU C's __attribute__).

This commit also moves all other function attributes to
the beginning of function declarations. "extern" is kept
at the beginning of a line so the attributes are listed on
separate lines before "extern" or "static".
2023-09-22 20:06:27 +03:00
Lasse Collin 18a66fbac0 Remove incorrect uses of __attribute__((__malloc__)).
xrealloc() is obviously incorrect, modern GCC docs even
mention realloc() as an example where this attribute
cannot be used.

liblzma's lzma_alloc() and lzma_alloc_zero() would be
correct uses most of the time but custom allocators
may use a memory pool or otherwise hold the pointer
so aliasing issues could happen in theory.

The xstrdup() case likely was correct but I removed it anyway.
Now there are no __malloc__ attributes left in the code.
The allocations aren't in hot paths so this should make
no practical difference.
2023-09-22 20:06:27 +03:00
Lasse Collin 90c94dddfd tuklib: Update tuklib_attr_noreturn for C11/C17 and C23.
This makes no difference for GCC or Clang as they support
GNU C's __attribute__((__noreturn__)) but this helps with MSVC:

  - VS 2019 version 16.7 and later support _Noreturn if the
    options /std:c11 or /std:c17 are used. This gets handled
    with the check for __STDC_VERSION__ >= 201112.

  - When MSVC isn't in C11/C17 mode, __declspec(noreturn) is used.

C23 will deprecate _Noreturn (and <stdnoreturn.h>)
for [[noreturn]]. This commit anticipates that but
the final __STDC_VERSION__ value isn't known yet.
2023-09-22 20:06:21 +03:00
Lasse Collin 79334e7f20 MSVC: xz: Make file_io.c and file_io.h compatible with MSVC.
Thanks to Kelvin Lee for the original patches
and testing the modifications I made.
2023-09-22 20:00:38 +03:00
Lasse Collin c660b8d78b MSVC: xz: Use GetTickCount64() to implement mytime_now().
It's available since Windows Vista.
2023-09-22 20:00:38 +03:00
Kelvin Lee 5c6f892d41 MSVC: xz: Use _stricmp() instead of strcasecmp() in suffix.c. 2023-09-22 20:00:38 +03:00
Kelvin Lee e241051f50 MSVC: xz: Use _isatty() from <io.h> to implement isatty(). 2023-09-22 20:00:38 +03:00