1*4882a593Smuzhiyun /* 2*4882a593Smuzhiyun * Definitions for handling the .xz file format 3*4882a593Smuzhiyun * 4*4882a593Smuzhiyun * Author: Lasse Collin <lasse.collin@tukaani.org> 5*4882a593Smuzhiyun * 6*4882a593Smuzhiyun * This file has been put into the public domain. 7*4882a593Smuzhiyun * You can do whatever you want with this file. 8*4882a593Smuzhiyun */ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #ifndef XZ_STREAM_H 11*4882a593Smuzhiyun #define XZ_STREAM_H 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun #if defined(__KERNEL__) && !XZ_INTERNAL_CRC32 14*4882a593Smuzhiyun # include <linux/crc32.h> 15*4882a593Smuzhiyun # undef crc32 16*4882a593Smuzhiyun # define xz_crc32(buf, size, crc) \ 17*4882a593Smuzhiyun (~crc32_le(~(uint32_t)(crc), buf, size)) 18*4882a593Smuzhiyun #endif 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun /* 21*4882a593Smuzhiyun * See the .xz file format specification at 22*4882a593Smuzhiyun * https://tukaani.org/xz/xz-file-format.txt 23*4882a593Smuzhiyun * to understand the container format. 24*4882a593Smuzhiyun */ 25*4882a593Smuzhiyun 26*4882a593Smuzhiyun #define STREAM_HEADER_SIZE 12 27*4882a593Smuzhiyun 28*4882a593Smuzhiyun #define HEADER_MAGIC "\3757zXZ" 29*4882a593Smuzhiyun #define HEADER_MAGIC_SIZE 6 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun #define FOOTER_MAGIC "YZ" 32*4882a593Smuzhiyun #define FOOTER_MAGIC_SIZE 2 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun /* 35*4882a593Smuzhiyun * Variable-length integer can hold a 63-bit unsigned integer or a special 36*4882a593Smuzhiyun * value indicating that the value is unknown. 37*4882a593Smuzhiyun * 38*4882a593Smuzhiyun * Experimental: vli_type can be defined to uint32_t to save a few bytes 39*4882a593Smuzhiyun * in code size (no effect on speed). Doing so limits the uncompressed and 40*4882a593Smuzhiyun * compressed size of the file to less than 256 MiB and may also weaken 41*4882a593Smuzhiyun * error detection slightly. 42*4882a593Smuzhiyun */ 43*4882a593Smuzhiyun typedef uint64_t vli_type; 44*4882a593Smuzhiyun 45*4882a593Smuzhiyun #define VLI_MAX ((vli_type)-1 / 2) 46*4882a593Smuzhiyun #define VLI_UNKNOWN ((vli_type)-1) 47*4882a593Smuzhiyun 48*4882a593Smuzhiyun /* Maximum encoded size of a VLI */ 49*4882a593Smuzhiyun #define VLI_BYTES_MAX (sizeof(vli_type) * 8 / 7) 50*4882a593Smuzhiyun 51*4882a593Smuzhiyun /* Integrity Check types */ 52*4882a593Smuzhiyun enum xz_check { 53*4882a593Smuzhiyun XZ_CHECK_NONE = 0, 54*4882a593Smuzhiyun XZ_CHECK_CRC32 = 1, 55*4882a593Smuzhiyun XZ_CHECK_CRC64 = 4, 56*4882a593Smuzhiyun XZ_CHECK_SHA256 = 10 57*4882a593Smuzhiyun }; 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun /* Maximum possible Check ID */ 60*4882a593Smuzhiyun #define XZ_CHECK_MAX 15 61*4882a593Smuzhiyun 62*4882a593Smuzhiyun #endif 63