From 833d4e7f84f59099ee66eabfa3457ebb7d37eaa8 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 3 Nov 2010 02:38:31 +0100 Subject: rename archival/libunarchive -> archival/libarchive; move bz/ into it Signed-off-by: Denys Vlasenko --- archival/libunarchive/unxz/README | 135 -------------------------------------- 1 file changed, 135 deletions(-) delete mode 100644 archival/libunarchive/unxz/README (limited to 'archival/libunarchive/unxz/README') diff --git a/archival/libunarchive/unxz/README b/archival/libunarchive/unxz/README deleted file mode 100644 index c5972f6b8..000000000 --- a/archival/libunarchive/unxz/README +++ /dev/null @@ -1,135 +0,0 @@ - -XZ Embedded -=========== - - XZ Embedded is a relatively small, limited implementation of the .xz - file format. Currently only decoding is implemented. - - XZ Embedded was written for use in the Linux kernel, but the code can - be easily used in other environments too, including regular userspace - applications. - - This README contains information that is useful only when the copy - of XZ Embedded isn't part of the Linux kernel tree. You should also - read linux/Documentation/xz.txt even if you aren't using XZ Embedded - as part of Linux; information in that file is not repeated in this - README. - -Compiling the Linux kernel module - - The xz_dec module depends on crc32 module, so make sure that you have - it enabled (CONFIG_CRC32). - - Building the xz_dec and xz_dec_test modules without support for BCJ - filters: - - cd linux/lib/xz - make -C /path/to/kernel/source \ - KCPPFLAGS=-I"$(pwd)/../../include" M="$(pwd)" \ - CONFIG_XZ_DEC=m CONFIG_XZ_DEC_TEST=m - - Building the xz_dec and xz_dec_test modules with support for BCJ - filters: - - cd linux/lib/xz - make -C /path/to/kernel/source \ - KCPPFLAGS=-I"$(pwd)/../../include" M="$(pwd)" \ - CONFIG_XZ_DEC=m CONFIG_XZ_DEC_TEST=m CONFIG_XZ_DEC_BCJ=y \ - CONFIG_XZ_DEC_X86=y CONFIG_XZ_DEC_POWERPC=y \ - CONFIG_XZ_DEC_IA64=y CONFIG_XZ_DEC_ARM=y \ - CONFIG_XZ_DEC_ARMTHUMB=y CONFIG_XZ_DEC_SPARC=y - - If you want only one or a few of the BCJ filters, omit the appropriate - variables. CONFIG_XZ_DEC_BCJ=y is always required to build the support - code shared between all BCJ filters. - - Most people don't need the xz_dec_test module. You can skip building - it by omitting CONFIG_XZ_DEC_TEST=m from the make command line. - -Compiler requirements - - XZ Embedded should compile as either GNU-C89 (used in the Linux - kernel) or with any C99 compiler. Getting the code to compile with - non-GNU C89 compiler or a C++ compiler should be quite easy as - long as there is a data type for unsigned 64-bit integer (or the - code is modified not to support large files, which needs some more - care than just using 32-bit integer instead of 64-bit). - - If you use GCC, try to use a recent version. For example, on x86, - xz_dec_lzma2.c compiled with GCC 3.3.6 is 15-25 % slower than when - compiled with GCC 4.3.3. - -Embedding into userspace applications - - To embed the XZ decoder, copy the following files into a single - directory in your source code tree: - - linux/include/linux/xz.h - linux/lib/xz/xz_crc32.c - linux/lib/xz/xz_dec_lzma2.c - linux/lib/xz/xz_dec_stream.c - linux/lib/xz/xz_lzma2.h - linux/lib/xz/xz_private.h - linux/lib/xz/xz_stream.h - userspace/xz_config.h - - Alternatively, xz.h may be placed into a different directory but then - that directory must be in the compiler include path when compiling - the .c files. - - Your code should use only the functions declared in xz.h. The rest of - the .h files are meant only for internal use in XZ Embedded. - - You may want to modify xz_config.h to be more suitable for your build - environment. Probably you should at least skim through it even if the - default file works as is. - -BCJ filter support - - If you want support for one or more BCJ filters, you need to copy also - linux/lib/xz/xz_dec_bcj.c into your application, and use appropriate - #defines in xz_config.h or in compiler flags. You don't need these - #defines in the code that just uses XZ Embedded via xz.h, but having - them always #defined doesn't hurt either. - - #define Instruction set BCJ filter endianness - XZ_DEC_X86 x86 or x86-64 Little endian only - XZ_DEC_POWERPC PowerPC Big endian only - XZ_DEC_IA64 Itanium (IA-64) Big or little endian - XZ_DEC_ARM ARM Little endian only - XZ_DEC_ARMTHUMB ARM-Thumb Little endian only - XZ_DEC_SPARC SPARC Big or little endian - - While some architectures are (partially) bi-endian, the endianness - setting doesn't change the endianness of the instructions on all - architectures. That's why Itanium and SPARC filters work for both big - and little endian executables (Itanium has little endian instructions - and SPARC has big endian instructions). - - There currently is no filter for little endian PowerPC or big endian - ARM or ARM-Thumb. Implementing filters for them can be considered if - there is a need for such filters in real-world applications. - -Notes about shared libraries - - If you are including XZ Embedded into a shared library, you very - probably should rename the xz_* functions to prevent symbol - conflicts in case your library is linked against some other library - or application that also has XZ Embedded in it (which may even be - a different version of XZ Embedded). TODO: Provide an easy way - to do this. - - Please don't create a shared library of XZ Embedded itself unless - it is fine to rebuild everything depending on that shared library - everytime you upgrade to a newer version of XZ Embedded. There are - no API or ABI stability guarantees between different versions of - XZ Embedded. - -Specifying the calling convention - - XZ_FUNC macro was included to support declaring functions with __init - in Linux. Outside Linux, it can be used to specify the calling - convention on systems that support multiple calling conventions. - For example, on Windows, you may make all functions use the stdcall - calling convention by defining XZ_FUNC=__stdcall when building and - using the functions from XZ Embedded. -- cgit v1.2.3