| /* xdelta 3 - delta compression tools and library |
| * Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, |
| * 2008, 2009, 2010. Joshua P. MacDonald |
| * |
| * This program 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 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program 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, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| /* To know more about Xdelta, start by reading xdelta3.c. If you are |
| * ready to use the API, continue reading here. There are two |
| * interfaces -- xd3_encode_input and xd3_decode_input -- plus a dozen |
| * or so related calls. This interface is styled after Zlib. */ |
| |
| #ifndef _XDELTA3_H_ |
| #define _XDELTA3_H_ |
| |
| #define _POSIX_SOURCE |
| #define _ISOC99_SOURCE |
| #define _C99_SOURCE |
| |
| #if HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <errno.h> |
| #include <stdarg.h> |
| #include <stddef.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/types.h> |
| |
| /****************************************************************/ |
| |
| /* Default configured value of stream->winsize. If the program |
| * supplies xd3_encode_input() with data smaller than winsize the |
| * stream will automatically buffer the input, otherwise the input |
| * buffer is used directly. |
| */ |
| #ifndef XD3_DEFAULT_WINSIZE |
| #define XD3_DEFAULT_WINSIZE (1U << 23) |
| #endif |
| |
| /* Default total size of the source window used in xdelta3-main.h */ |
| #ifndef XD3_DEFAULT_SRCWINSZ |
| #define XD3_DEFAULT_SRCWINSZ (1U << 26) |
| #endif |
| |
| /* When Xdelta requests a memory allocation for certain buffers, it |
| * rounds up to units of at least this size. The code assumes (and |
| * asserts) that this is a power-of-two. */ |
| #ifndef XD3_ALLOCSIZE |
| #define XD3_ALLOCSIZE (1U<<14) |
| #endif |
| |
| /* The XD3_HARDMAXWINSIZE parameter is a safety mechanism to protect |
| * decoders against malicious files. The decoder will never decode a |
| * window larger than this. If the file specifies VCD_TARGET the |
| * decoder may require two buffers of this size. |
| * |
| * 8-16MB is reasonable, probably don't need to go larger. */ |
| #ifndef XD3_HARDMAXWINSIZE |
| #define XD3_HARDMAXWINSIZE (1U<<24) |
| #endif |
| /* The IOPT_SIZE value sets the size of a buffer used to batch |
| * overlapping copy instructions before they are optimized by picking |
| * the best non-overlapping ranges. The larger this buffer, the |
| * longer a forced xd3_srcwin_setup() decision is held off. Setting |
| * this value to 0 causes an unlimited buffer to be used. */ |
| #ifndef XD3_DEFAULT_IOPT_SIZE |
| #define XD3_DEFAULT_IOPT_SIZE (1U<<15) |
| #endif |
| |
| /* The maximum distance backward to search for small matches */ |
| #ifndef XD3_DEFAULT_SPREVSZ |
| #define XD3_DEFAULT_SPREVSZ (1U<<18) |
| #endif |
| |
| /* The default compression level |
| */ |
| #ifndef XD3_DEFAULT_LEVEL |
| #define XD3_DEFAULT_LEVEL 3 |
| #endif |
| |
| #ifndef XD3_DEFAULT_SECONDARY_LEVEL |
| #define XD3_DEFAULT_SECONDARY_LEVEL 6 |
| #endif |
| |
| #ifndef XD3_USE_LARGEFILE64 |
| #define XD3_USE_LARGEFILE64 1 |
| #endif |
| |
| /* Sizes and addresses within VCDIFF windows are represented as usize_t |
| * |
| * For source-file offsets and total file sizes, total input and |
| * output counts, the xoff_t type is used. The decoder and encoder |
| * generally check for overflow of the xoff_t size (this is tested at |
| * the 32bit boundary [xdelta3-test.h]). |
| */ |
| #ifndef _WIN32 |
| #include <stdint.h> |
| #else |
| #define WIN32_LEAN_AND_MEAN |
| #if XD3_USE_LARGEFILE64 |
| /* 64 bit file offsets: uses GetFileSizeEx and SetFilePointerEx. |
| * requires Win2000 or newer version of WinNT */ |
| #define WINVER 0x0500 |
| #define _WIN32_WINNT 0x0500 |
| #else |
| /* 32 bit (DWORD) file offsets: uses GetFileSize and |
| * SetFilePointer. compatible with win9x-me and WinNT4 */ |
| #define WINVER 0x0400 |
| #define _WIN32_WINNT 0x0400 |
| #endif |
| #include <windows.h> |
| #ifdef _MSC_VER |
| #define inline |
| typedef signed int ssize_t; |
| #if _MSC_VER < 1600 |
| typedef unsigned char uint8_t; |
| typedef unsigned short uint16_t; |
| typedef unsigned long uint32_t; |
| typedef ULONGLONG uint64_t; |
| #else |
| /* For MSVC10 and above */ |
| #include <stdint.h> |
| #endif |
| #else |
| /* mingw32, lcc and watcom provide a proper header */ |
| #include <stdint.h> |
| #endif |
| #endif |
| |
| typedef uint32_t usize_t; |
| |
| #if XD3_USE_LARGEFILE64 |
| #define __USE_FILE_OFFSET64 1 /* GLIBC: for 64bit fileops, ... ? */ |
| #ifndef _LARGEFILE_SOURCE |
| #define _LARGEFILE_SOURCE |
| #endif |
| #ifndef _FILE_OFFSET_BITS |
| #define _FILE_OFFSET_BITS 64 |
| #endif |
| |
| typedef uint64_t xoff_t; |
| #define SIZEOF_XOFF_T 8 |
| #define SIZEOF_USIZE_T 4 |
| #ifndef WIN32 |
| #define Q "ll" |
| #else |
| #define Q "I64" |
| #endif |
| #else |
| typedef uint32_t xoff_t; |
| #define SIZEOF_XOFF_T 4 |
| #define SIZEOF_USIZE_T 4 |
| #define Q |
| #endif |
| |
| #define USE_UINT32 (SIZEOF_USIZE_T == 4 || \ |
| SIZEOF_XOFF_T == 4 || REGRESSION_TEST) |
| #define USE_UINT64 (SIZEOF_USIZE_T == 8 || \ |
| SIZEOF_XOFF_T == 8 || REGRESSION_TEST) |
| |
| #ifndef UNALIGNED_OK |
| #ifdef HAVE_ALIGNED_ACCESS_REQUIRED |
| #define UNALIGNED_OK 0 |
| #else |
| /* This generally includes all Windows builds. */ |
| #define UNALIGNED_OK 1 |
| #endif |
| #endif |
| |
| /**********************************************************************/ |
| |
| /* Whether to build the encoder, otherwise only build the decoder. */ |
| #ifndef XD3_ENCODER |
| #define XD3_ENCODER 1 |
| #endif |
| |
| /* The code returned when main() fails, also defined in system |
| includes. */ |
| #ifndef EXIT_FAILURE |
| #define EXIT_FAILURE 1 |
| #endif |
| |
| /* REGRESSION TEST enables the "xdelta3 test" command, which runs a |
| series of self-tests. */ |
| #ifndef REGRESSION_TEST |
| #define REGRESSION_TEST 0 |
| #endif |
| |
| /* XD3_DEBUG=1 enables assertions and various statistics. Levels > 1 |
| * enable some additional output only useful during development and |
| * debugging. */ |
| #ifndef XD3_DEBUG |
| #define XD3_DEBUG 0 |
| #endif |
| |
| #ifndef PYTHON_MODULE |
| #define PYTHON_MODULE 0 |
| #endif |
| |
| #ifndef SWIG_MODULE |
| #define SWIG_MODULE 0 |
| #endif |
| |
| /* There are three string matching functions supplied: one fast, one |
| * slow (default), and one soft-configurable. To disable any of |
| * these, use the following definitions. */ |
| #ifndef XD3_BUILD_SLOW |
| #define XD3_BUILD_SLOW 1 |
| #endif |
| #ifndef XD3_BUILD_FAST |
| #define XD3_BUILD_FAST 1 |
| #endif |
| #ifndef XD3_BUILD_FASTER |
| #define XD3_BUILD_FASTER 1 |
| #endif |
| #ifndef XD3_BUILD_FASTEST |
| #define XD3_BUILD_FASTEST 1 |
| #endif |
| #ifndef XD3_BUILD_SOFT |
| #define XD3_BUILD_SOFT 1 |
| #endif |
| #ifndef XD3_BUILD_DEFAULT |
| #define XD3_BUILD_DEFAULT 1 |
| #endif |
| |
| #if XD3_DEBUG |
| #include <stdio.h> |
| #endif |
| |
| /* XPRINT. Debug output and VCDIFF_TOOLS functions report to stderr. |
| * I have used an irregular style to abbreviate [fprintf(stderr, "] as |
| * [DP(RINT "]. */ |
| #define DP fprintf |
| #define RINT stderr, |
| |
| typedef struct _xd3_stream xd3_stream; |
| typedef struct _xd3_source xd3_source; |
| typedef struct _xd3_hash_cfg xd3_hash_cfg; |
| typedef struct _xd3_smatcher xd3_smatcher; |
| typedef struct _xd3_rinst xd3_rinst; |
| typedef struct _xd3_dinst xd3_dinst; |
| typedef struct _xd3_hinst xd3_hinst; |
| typedef struct _xd3_winst xd3_winst; |
| typedef struct _xd3_rpage xd3_rpage; |
| typedef struct _xd3_addr_cache xd3_addr_cache; |
| typedef struct _xd3_output xd3_output; |
| typedef struct _xd3_desect xd3_desect; |
| typedef struct _xd3_iopt_buflist xd3_iopt_buflist; |
| typedef struct _xd3_rlist xd3_rlist; |
| typedef struct _xd3_sec_type xd3_sec_type; |
| typedef struct _xd3_sec_cfg xd3_sec_cfg; |
| typedef struct _xd3_sec_stream xd3_sec_stream; |
| typedef struct _xd3_config xd3_config; |
| typedef struct _xd3_code_table_desc xd3_code_table_desc; |
| typedef struct _xd3_code_table_sizes xd3_code_table_sizes; |
| typedef struct _xd3_slist xd3_slist; |
| typedef struct _xd3_whole_state xd3_whole_state; |
| typedef struct _xd3_wininfo xd3_wininfo; |
| |
| /* The stream configuration has three callbacks functions, all of |
| * which may be supplied with NULL values. If config->getblk is |
| * provided as NULL, the stream returns XD3_GETSRCBLK. */ |
| |
| typedef void* (xd3_alloc_func) (void *opaque, |
| size_t items, |
| usize_t size); |
| typedef void (xd3_free_func) (void *opaque, |
| void *address); |
| |
| typedef int (xd3_getblk_func) (xd3_stream *stream, |
| xd3_source *source, |
| xoff_t blkno); |
| |
| /* These are internal functions to delay construction of encoding |
| * tables and support alternate code tables. See the comments & code |
| * enabled by GENERIC_ENCODE_TABLES. */ |
| |
| typedef const xd3_dinst* (xd3_code_table_func) (void); |
| typedef int (xd3_comp_table_func) (xd3_stream *stream, |
| const uint8_t **data, |
| usize_t *size); |
| |
| |
| |
| #if XD3_DEBUG |
| #define XD3_ASSERT(x) \ |
| do { if (! (x)) { DP(RINT "%s:%d: XD3 assertion failed: %s\n", __FILE__, __LINE__, #x); \ |
| abort (); } } while (0) |
| #else |
| #define XD3_ASSERT(x) (void)0 |
| #endif /* XD3_DEBUG */ |
| |
| #ifndef max |
| #define max(x,y) ((x) < (y) ? (y) : (x)) |
| #endif |
| #ifndef min |
| #define min(x,y) ((x) < (y) ? (x) : (y)) |
| #endif |
| |
| /**************************************************************** |
| PUBLIC ENUMS |
| ******************************************************************/ |
| |
| /* These are the five ordinary status codes returned by the |
| * xd3_encode_input() and xd3_decode_input() state machines. */ |
| typedef enum { |
| |
| /* An application must be prepared to handle these five return |
| * values from either xd3_encode_input or xd3_decode_input, except |
| * in the case of no-source compression, in which case XD3_GETSRCBLK |
| * is never returned. More detailed comments for these are given in |
| * xd3_encode_input and xd3_decode_input comments, below. */ |
| XD3_INPUT = -17703, /* need input */ |
| XD3_OUTPUT = -17704, /* have output */ |
| XD3_GETSRCBLK = -17705, /* need a block of source input (with no |
| * xd3_getblk function), a chance to do |
| * non-blocking read. */ |
| XD3_GOTHEADER = -17706, /* (decode-only) after the initial VCDIFF & |
| first window header */ |
| XD3_WINSTART = -17707, /* notification: returned before a window is |
| * processed, giving a chance to |
| * XD3_SKIP_WINDOW or not XD3_SKIP_EMIT that |
| * window. */ |
| XD3_WINFINISH = -17708, /* notification: returned after |
| encode/decode & output for a window */ |
| XD3_TOOFARBACK = -17709, /* (encoder only) may be returned by |
| getblk() if the block is too old */ |
| XD3_INTERNAL = -17710, /* internal error */ |
| XD3_INVALID = -17711, /* invalid config */ |
| XD3_INVALID_INPUT = -17712, /* invalid input/decoder error */ |
| XD3_NOSECOND = -17713, /* when secondary compression finds no |
| improvement. */ |
| XD3_UNIMPLEMENTED = -17714 /* currently VCD_TARGET */ |
| } xd3_rvalues; |
| |
| /* special values in config->flags */ |
| typedef enum |
| { |
| XD3_JUST_HDR = (1 << 1), /* used by VCDIFF tools, see |
| xdelta3-main.h. */ |
| XD3_SKIP_WINDOW = (1 << 2), /* used by VCDIFF tools, see |
| xdelta3-main.h. */ |
| XD3_SKIP_EMIT = (1 << 3), /* used by VCDIFF tools, see |
| xdelta3-main.h. */ |
| XD3_FLUSH = (1 << 4), /* flush the stream buffer to |
| prepare for |
| xd3_stream_close(). */ |
| |
| XD3_SEC_DJW = (1 << 5), /* use DJW static huffman */ |
| XD3_SEC_FGK = (1 << 6), /* use FGK adaptive huffman */ |
| XD3_SEC_LZMA = (1 << 24), /* use LZMA secondary */ |
| |
| XD3_SEC_TYPE = (XD3_SEC_DJW | XD3_SEC_FGK | XD3_SEC_LZMA), |
| |
| XD3_SEC_NODATA = (1 << 7), /* disable secondary compression of |
| the data section. */ |
| XD3_SEC_NOINST = (1 << 8), /* disable secondary compression of |
| the inst section. */ |
| XD3_SEC_NOADDR = (1 << 9), /* disable secondary compression of |
| the addr section. */ |
| |
| XD3_SEC_NOALL = (XD3_SEC_NODATA | XD3_SEC_NOINST | XD3_SEC_NOADDR), |
| |
| XD3_ADLER32 = (1 << 10), /* enable checksum computation in |
| the encoder. */ |
| XD3_ADLER32_NOVER = (1 << 11), /* disable checksum verification in |
| the decoder. */ |
| |
| XD3_ALT_CODE_TABLE = (1 << 12), /* for testing th |
| e alternate code table encoding. */ |
| |
| XD3_NOCOMPRESS = (1 << 13), /* disable ordinary data |
| * compression feature, only search |
| * the source, not the target. */ |
| XD3_BEGREEDY = (1 << 14), /* disable the "1.5-pass |
| * algorithm", instead use greedy |
| * matching. Greedy is off by |
| * default. */ |
| XD3_ADLER32_RECODE = (1 << 15), /* used by "recode". */ |
| |
| /* 4 bits to set the compression level the same as the command-line |
| * setting -1 through -9 (-0 corresponds to the XD3_NOCOMPRESS flag, |
| * and is independent of compression level). This is for |
| * convenience, especially with xd3_encode_memory(). */ |
| |
| XD3_COMPLEVEL_SHIFT = 20, /* 20 - 23 */ |
| XD3_COMPLEVEL_MASK = (0xF << XD3_COMPLEVEL_SHIFT), |
| XD3_COMPLEVEL_1 = (1 << XD3_COMPLEVEL_SHIFT), |
| XD3_COMPLEVEL_2 = (2 << XD3_COMPLEVEL_SHIFT), |
| XD3_COMPLEVEL_3 = (3 << XD3_COMPLEVEL_SHIFT), |
| XD3_COMPLEVEL_6 = (6 << XD3_COMPLEVEL_SHIFT), |
| XD3_COMPLEVEL_9 = (9 << XD3_COMPLEVEL_SHIFT) |
| |
| } xd3_flags; |
| |
| /* The values of this enumeration are set in xd3_config using the |
| * smatch_cfg variable. It can be set to default, slow, fast, etc., |
| * and soft. */ |
| typedef enum |
| { |
| XD3_SMATCH_DEFAULT = 0, /* Flags may contain XD3_COMPLEVEL bits, |
| else default. */ |
| XD3_SMATCH_SLOW = 1, |
| XD3_SMATCH_FAST = 2, |
| XD3_SMATCH_FASTER = 3, |
| XD3_SMATCH_FASTEST = 4, |
| XD3_SMATCH_SOFT = 5 |
| } xd3_smatch_cfg; |
| |
| /********************************************************************* |
| PRIVATE ENUMS |
| **********************************************************************/ |
| |
| /* stream->match_state is part of the xd3_encode_input state machine |
| * for source matching: |
| * |
| * 1. the XD3_GETSRCBLK block-read mechanism means reentrant matching |
| * 2. this state spans encoder windows: a match and end-of-window |
| * will continue in the next 3. the initial target byte and source |
| * byte are a presumed match, to avoid some computation in case the |
| * inputs are identical. |
| */ |
| typedef enum { |
| |
| MATCH_TARGET = 0, /* in this state, attempt to match the start of |
| * the target with the previously set source |
| * address (initially 0). */ |
| MATCH_BACKWARD = 1, /* currently expanding a match backward in the |
| source/target. */ |
| MATCH_FORWARD = 2, /* currently expanding a match forward in the |
| source/target. */ |
| MATCH_SEARCHING = 3 /* currently searching for a match. */ |
| |
| } xd3_match_state; |
| |
| /* The xd3_encode_input state machine steps through these states in |
| * the following order. The matcher is reentrant and returns |
| * XD3_INPUT whenever it requires more data. After receiving |
| * XD3_INPUT, if the application reads EOF it should call |
| * xd3_stream_close(). |
| */ |
| typedef enum { |
| |
| ENC_INIT = 0, /* xd3_encode_input has never been called. */ |
| ENC_INPUT = 1, /* waiting for xd3_avail_input () to be called. */ |
| ENC_SEARCH = 2, /* currently searching for matches. */ |
| ENC_INSTR = 3, /* currently formatting output. */ |
| ENC_FLUSH = 4, /* currently emitting output. */ |
| ENC_POSTOUT = 5, /* after an output section. */ |
| ENC_POSTWIN = 6, /* after all output sections. */ |
| ENC_ABORTED = 7 /* abort. */ |
| } xd3_encode_state; |
| |
| /* The xd3_decode_input state machine steps through these states in |
| * the following order. The matcher is reentrant and returns |
| * XD3_INPUT whenever it requires more data. After receiving |
| * XD3_INPUT, if the application reads EOF it should call |
| * xd3_stream_close(). |
| * |
| * 0-8: the VCDIFF header |
| * 9-18: the VCDIFF window header |
| * 19-21: the three primary sections: data, inst, addr |
| * 22: producing output: returns XD3_OUTPUT, possibly XD3_GETSRCBLK, |
| * 23: return XD3_WINFINISH, set state=9 to decode more input |
| */ |
| typedef enum { |
| |
| DEC_VCHEAD = 0, /* VCDIFF header */ |
| DEC_HDRIND = 1, /* header indicator */ |
| |
| DEC_SECONDID = 2, /* secondary compressor ID */ |
| |
| DEC_TABLEN = 3, /* code table length */ |
| DEC_NEAR = 4, /* code table near */ |
| DEC_SAME = 5, /* code table same */ |
| DEC_TABDAT = 6, /* code table data */ |
| |
| DEC_APPLEN = 7, /* application data length */ |
| DEC_APPDAT = 8, /* application data */ |
| |
| DEC_WININD = 9, /* window indicator */ |
| |
| DEC_CPYLEN = 10, /* copy window length */ |
| DEC_CPYOFF = 11, /* copy window offset */ |
| |
| DEC_ENCLEN = 12, /* length of delta encoding */ |
| DEC_TGTLEN = 13, /* length of target window */ |
| DEC_DELIND = 14, /* delta indicator */ |
| |
| DEC_DATALEN = 15, /* length of ADD+RUN data */ |
| DEC_INSTLEN = 16, /* length of instruction data */ |
| DEC_ADDRLEN = 17, /* length of address data */ |
| |
| DEC_CKSUM = 18, /* window checksum */ |
| |
| DEC_DATA = 19, /* data section */ |
| DEC_INST = 20, /* instruction section */ |
| DEC_ADDR = 21, /* address section */ |
| |
| DEC_EMIT = 22, /* producing data */ |
| |
| DEC_FINISH = 23, /* window finished */ |
| |
| DEC_ABORTED = 24 /* xd3_abort_stream */ |
| } xd3_decode_state; |
| |
| /************************************************************ |
| internal types |
| ************************************************************/ |
| |
| /* instruction lists used in the IOPT buffer */ |
| struct _xd3_rlist |
| { |
| xd3_rlist *next; |
| xd3_rlist *prev; |
| }; |
| |
| /* the raw encoding of an instruction used in the IOPT buffer */ |
| struct _xd3_rinst |
| { |
| uint8_t type; |
| uint8_t xtra; |
| uint8_t code1; |
| uint8_t code2; |
| usize_t pos; |
| usize_t size; |
| xoff_t addr; |
| xd3_rlist link; |
| }; |
| |
| /* the code-table form of an single- or double-instruction */ |
| struct _xd3_dinst |
| { |
| uint8_t type1; |
| uint8_t size1; |
| uint8_t type2; |
| uint8_t size2; |
| }; |
| |
| /* the decoded form of a single (half) instruction. */ |
| struct _xd3_hinst |
| { |
| uint8_t type; |
| uint32_t size; /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t addr; /* TODO: why decode breaks if this is usize_t? */ |
| }; |
| |
| /* the form of a whole-file instruction */ |
| struct _xd3_winst |
| { |
| uint8_t type; /* RUN, ADD, COPY */ |
| uint8_t mode; /* 0, VCD_SOURCE, VCD_TARGET */ |
| usize_t size; |
| xoff_t addr; |
| xoff_t position; /* absolute position of this inst */ |
| }; |
| |
| /* used by the encoder to buffer output in sections. list of blocks. */ |
| struct _xd3_output |
| { |
| uint8_t *base; |
| usize_t next; |
| usize_t avail; |
| xd3_output *next_page; |
| }; |
| |
| /* used by the decoder to buffer input in sections. */ |
| struct _xd3_desect |
| { |
| const uint8_t *buf; |
| const uint8_t *buf_max; |
| uint32_t size; /* TODO: why decode breaks if this is usize_t? */ |
| usize_t pos; |
| |
| /* used in xdelta3-decode.h */ |
| uint8_t *copied1; |
| usize_t alloc1; |
| |
| /* used in xdelta3-second.h */ |
| uint8_t *copied2; |
| usize_t alloc2; |
| }; |
| |
| /* the VCDIFF address cache, see the RFC */ |
| struct _xd3_addr_cache |
| { |
| usize_t s_near; |
| usize_t s_same; |
| usize_t next_slot; /* the circular index for near */ |
| usize_t *near_array; /* array of size s_near */ |
| usize_t *same_array; /* array of size s_same*256 */ |
| }; |
| |
| /* the IOPT buffer list is just a list of buffers, which may be allocated |
| * during encode when using an unlimited buffer. */ |
| struct _xd3_iopt_buflist |
| { |
| xd3_rinst *buffer; |
| xd3_iopt_buflist *next; |
| }; |
| |
| /* This is the record of a pre-compiled configuration, a subset of |
| xd3_config. */ |
| struct _xd3_smatcher |
| { |
| const char *name; |
| int (*string_match) (xd3_stream *stream); |
| usize_t large_look; |
| usize_t large_step; |
| usize_t small_look; |
| usize_t small_chain; |
| usize_t small_lchain; |
| usize_t max_lazy; |
| usize_t long_enough; |
| }; |
| |
| /* hash table size & power-of-two hash function. */ |
| struct _xd3_hash_cfg |
| { |
| usize_t size; |
| usize_t shift; |
| usize_t mask; |
| }; |
| |
| /* the sprev list */ |
| struct _xd3_slist |
| { |
| usize_t last_pos; |
| }; |
| |
| /* window info (for whole state) */ |
| struct _xd3_wininfo { |
| xoff_t offset; |
| usize_t length; |
| uint32_t adler32; |
| }; |
| |
| /* whole state for, e.g., merge */ |
| struct _xd3_whole_state { |
| usize_t addslen; |
| uint8_t *adds; |
| usize_t adds_alloc; |
| |
| usize_t instlen; |
| xd3_winst *inst; |
| usize_t inst_alloc; |
| |
| usize_t wininfolen; |
| xd3_wininfo *wininfo; |
| usize_t wininfo_alloc; |
| |
| xoff_t length; |
| }; |
| |
| /******************************************************************** |
| public types |
| *******************************************************************/ |
| |
| /* Settings for the secondary compressor. */ |
| struct _xd3_sec_cfg |
| { |
| int data_type; /* Which section. (set automatically) */ |
| usize_t ngroups; /* Number of DJW Huffman groups. */ |
| usize_t sector_size; /* Sector size. */ |
| int inefficient; /* If true, ignore efficiency check [avoid XD3_NOSECOND]. */ |
| }; |
| |
| /* This is the user-visible stream configuration. */ |
| struct _xd3_config |
| { |
| usize_t winsize; /* The encoder window size. */ |
| usize_t sprevsz; /* How far back small string |
| matching goes */ |
| usize_t iopt_size; /* entries in the |
| instruction-optimizing |
| buffer */ |
| |
| xd3_getblk_func *getblk; /* The three callbacks. */ |
| xd3_alloc_func *alloc; |
| xd3_free_func *freef; |
| void *opaque; /* Not used. */ |
| int flags; /* stream->flags are initialized |
| * from xd3_config & never |
| * modified by the library. Use |
| * xd3_set_flags to modify flags |
| * settings mid-stream. */ |
| |
| xd3_sec_cfg sec_data; /* Secondary compressor config: data */ |
| xd3_sec_cfg sec_inst; /* Secondary compressor config: inst */ |
| xd3_sec_cfg sec_addr; /* Secondary compressor config: addr */ |
| |
| xd3_smatch_cfg smatch_cfg; /* See enum: use fields below for |
| soft config */ |
| xd3_smatcher smatcher_soft; |
| }; |
| |
| /* The primary source file object. You create one of these objects and |
| * initialize the first four fields. This library maintains the next |
| * 5 fields. The configured getblk implementation is responsible for |
| * setting the final 3 fields when called (and/or when XD3_GETSRCBLK |
| * is returned). |
| */ |
| struct _xd3_source |
| { |
| /* you set */ |
| usize_t blksize; /* block size */ |
| const char *name; /* its name, for debug/print |
| purposes */ |
| void *ioh; /* opaque handle */ |
| xoff_t max_winsize; /* maximum visible buffer */ |
| |
| /* getblk sets */ |
| xoff_t curblkno; /* current block number: client |
| sets after getblk request */ |
| usize_t onblk; /* number of bytes on current |
| block: client sets, must be >= 0 |
| and <= blksize */ |
| const uint8_t *curblk; /* current block array: client |
| sets after getblk request */ |
| |
| /* xd3 sets */ |
| usize_t srclen; /* length of this source window */ |
| xoff_t srcbase; /* offset of this source window |
| in the source itself */ |
| int shiftby; /* for power-of-two blocksizes */ |
| int maskby; /* for power-of-two blocksizes */ |
| xoff_t cpyoff_blocks; /* offset of dec_cpyoff in blocks */ |
| usize_t cpyoff_blkoff; /* offset of copy window in |
| blocks, remainder */ |
| xoff_t getblkno; /* request block number: xd3 sets |
| current getblk request */ |
| |
| /* See xd3_getblk() */ |
| xoff_t max_blkno; /* Maximum block, if eof is known, |
| * otherwise, equals frontier_blkno |
| * (initially 0). */ |
| xoff_t frontier_blkno; /* If eof is unknown, the next |
| * source position to be read. |
| * Otherwise, equal to |
| * max_blkno. */ |
| usize_t onlastblk; /* Number of bytes on max_blkno */ |
| int eof_known; /* Set to true when the first |
| * partial block is read. */ |
| }; |
| |
| /* The primary xd3_stream object, used for encoding and decoding. You |
| * may access only two fields: avail_out, next_out. Use the methods |
| * above to operate on xd3_stream. */ |
| struct _xd3_stream |
| { |
| /* input state */ |
| const uint8_t *next_in; /* next input byte */ |
| usize_t avail_in; /* number of bytes available at |
| next_in */ |
| xoff_t total_in; /* how many bytes in */ |
| |
| /* output state */ |
| uint8_t *next_out; /* next output byte */ |
| usize_t avail_out; /* number of bytes available at |
| next_out */ |
| usize_t space_out; /* total out space */ |
| xoff_t current_window; /* number of windows encoded/decoded */ |
| xoff_t total_out; /* how many bytes out */ |
| |
| /* to indicate an error, xd3 sets */ |
| const char *msg; /* last error message, NULL if |
| no error */ |
| |
| /* source configuration */ |
| xd3_source *src; /* source array */ |
| |
| /* encoder memory configuration */ |
| usize_t winsize; /* suggested window size */ |
| usize_t sprevsz; /* small string, previous window |
| size (power of 2) */ |
| usize_t sprevmask; /* small string, previous window |
| size mask */ |
| usize_t iopt_size; |
| usize_t iopt_unlimited; |
| |
| /* general configuration */ |
| xd3_getblk_func *getblk; /* set nxtblk, nxtblkno to scanblkno */ |
| xd3_alloc_func *alloc; /* malloc function */ |
| xd3_free_func *free; /* free function */ |
| void* opaque; /* private data object passed to |
| alloc, free, and getblk */ |
| int flags; /* various options */ |
| |
| /* secondary compressor configuration */ |
| xd3_sec_cfg sec_data; /* Secondary compressor config: data */ |
| xd3_sec_cfg sec_inst; /* Secondary compressor config: inst */ |
| xd3_sec_cfg sec_addr; /* Secondary compressor config: addr */ |
| |
| xd3_smatcher smatcher; |
| |
| usize_t *large_table; /* table of large checksums */ |
| xd3_hash_cfg large_hash; /* large hash config */ |
| |
| usize_t *small_table; /* table of small checksums */ |
| xd3_slist *small_prev; /* table of previous offsets, |
| circular linked list */ |
| int small_reset; /* true if small table should |
| be reset */ |
| |
| xd3_hash_cfg small_hash; /* small hash config */ |
| xd3_addr_cache acache; /* the vcdiff address cache */ |
| xd3_encode_state enc_state; /* state of the encoder */ |
| |
| usize_t taroff; /* base offset of the target input */ |
| usize_t input_position; /* current input position */ |
| usize_t min_match; /* current minimum match |
| length, avoids redundent |
| matches */ |
| usize_t unencoded_offset; /* current input, first |
| * unencoded offset. this value |
| * is <= the first instruction's |
| * position in the iopt buffer, |
| * if there is at least one |
| * match in the buffer. */ |
| |
| /* SRCWIN */ |
| int srcwin_decided; /* boolean: true if srclen and |
| srcbase have been |
| decided. */ |
| int srcwin_decided_early; /* boolean: true if srclen |
| and srcbase were |
| decided early. */ |
| xoff_t srcwin_cksum_pos; /* Source checksum position */ |
| |
| /* MATCH */ |
| xd3_match_state match_state; /* encoder match state */ |
| xoff_t match_srcpos; /* current match source |
| position relative to |
| srcbase */ |
| xoff_t match_last_srcpos; /* previously attempted |
| * srcpos, to avoid loops. */ |
| xoff_t match_minaddr; /* smallest matching address to |
| * set window params (reset each |
| * window xd3_encode_reset) */ |
| xoff_t match_maxaddr; /* largest matching address to |
| * set window params (reset each |
| * window xd3_encode_reset) */ |
| usize_t match_back; /* match extends back so far */ |
| usize_t match_maxback; /* match extends back maximum */ |
| usize_t match_fwd; /* match extends forward so far */ |
| usize_t match_maxfwd; /* match extends forward maximum */ |
| |
| xoff_t maxsrcaddr; /* address of the last source |
| match (across windows) */ |
| |
| uint8_t *buf_in; /* for saving buffered input */ |
| usize_t buf_avail; /* amount of saved input */ |
| const uint8_t *buf_leftover; /* leftover content of next_in |
| (i.e., user's buffer) */ |
| usize_t buf_leftavail; /* amount of leftover content */ |
| |
| xd3_output *enc_current; /* current output buffer */ |
| xd3_output *enc_free; /* free output buffers */ |
| xd3_output *enc_heads[4]; /* array of encoded outputs: |
| head of chain */ |
| xd3_output *enc_tails[4]; /* array of encoded outputs: |
| tail of chain */ |
| uint32_t recode_adler32; /* set the adler32 checksum |
| * during "recode". */ |
| |
| xd3_rlist iopt_used; /* instruction optimizing buffer */ |
| xd3_rlist iopt_free; |
| xd3_rinst *iout; /* next single instruction */ |
| xd3_iopt_buflist *iopt_alloc; |
| |
| const uint8_t *enc_appheader; /* application header to encode */ |
| usize_t enc_appheadsz; /* application header size */ |
| |
| /* decoder stuff */ |
| xd3_decode_state dec_state; /* current DEC_XXX value */ |
| usize_t dec_hdr_ind; /* VCDIFF header indicator */ |
| usize_t dec_win_ind; /* VCDIFF window indicator */ |
| usize_t dec_del_ind; /* VCDIFF delta indicator */ |
| |
| uint8_t dec_magic[4]; /* First four bytes */ |
| usize_t dec_magicbytes; /* Magic position. */ |
| |
| usize_t dec_secondid; /* Optional secondary compressor ID. */ |
| |
| /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t dec_codetblsz; /* Optional code table: length. */ |
| uint8_t *dec_codetbl; /* Optional code table: storage. */ |
| usize_t dec_codetblbytes; /* Optional code table: position. */ |
| |
| /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t dec_appheadsz; /* Optional application header: |
| size. */ |
| uint8_t *dec_appheader; /* Optional application header: |
| storage */ |
| usize_t dec_appheadbytes; /* Optional application header: |
| position. */ |
| |
| usize_t dec_cksumbytes; /* Optional checksum: position. */ |
| uint8_t dec_cksum[4]; /* Optional checksum: storage. */ |
| uint32_t dec_adler32; /* Optional checksum: value. */ |
| |
| /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t dec_cpylen; /* length of copy window |
| (VCD_SOURCE or VCD_TARGET) */ |
| xoff_t dec_cpyoff; /* offset of copy window |
| (VCD_SOURCE or VCD_TARGET) */ |
| /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t dec_enclen; /* length of delta encoding */ |
| /* TODO: why decode breaks if this is usize_t? */ |
| uint32_t dec_tgtlen; /* length of target window */ |
| |
| #if USE_UINT64 |
| uint64_t dec_64part; /* part of a decoded uint64_t */ |
| #endif |
| #if USE_UINT32 |
| uint32_t dec_32part; /* part of a decoded uint32_t */ |
| #endif |
| |
| xoff_t dec_winstart; /* offset of the start of |
| current target window */ |
| xoff_t dec_window_count; /* == current_window + 1 in |
| DEC_FINISH */ |
| usize_t dec_winbytes; /* bytes of the three sections |
| so far consumed */ |
| usize_t dec_hdrsize; /* VCDIFF + app header size */ |
| |
| const uint8_t *dec_tgtaddrbase; /* Base of decoded target |
| addresses (addr >= |
| dec_cpylen). */ |
| const uint8_t *dec_cpyaddrbase; /* Base of decoded copy |
| addresses (addr < |
| dec_cpylen). */ |
| |
| usize_t dec_position; /* current decoder position |
| counting the cpylen |
| offset */ |
| usize_t dec_maxpos; /* maximum decoder position |
| counting the cpylen |
| offset */ |
| xd3_hinst dec_current1; /* current instruction */ |
| xd3_hinst dec_current2; /* current instruction */ |
| |
| uint8_t *dec_buffer; /* Decode buffer */ |
| uint8_t *dec_lastwin; /* In case of VCD_TARGET, the |
| last target window. */ |
| usize_t dec_lastlen; /* length of the last target |
| window */ |
| xoff_t dec_laststart; /* offset of the start of last |
| target window */ |
| usize_t dec_lastspace; /* allocated space of last |
| target window, for reuse */ |
| |
| xd3_desect inst_sect; /* staging area for decoding |
| window sections */ |
| xd3_desect addr_sect; |
| xd3_desect data_sect; |
| |
| xd3_code_table_func *code_table_func; |
| xd3_comp_table_func *comp_table_func; |
| const xd3_dinst *code_table; |
| const xd3_code_table_desc *code_table_desc; |
| xd3_dinst *code_table_alloc; |
| |
| /* secondary compression */ |
| const xd3_sec_type *sec_type; |
| xd3_sec_stream *sec_stream_d; |
| xd3_sec_stream *sec_stream_i; |
| xd3_sec_stream *sec_stream_a; |
| |
| /* state for reconstructing whole files (e.g., for merge), this only |
| * supports loading USIZE_T_MAX instructions, adds, etc. */ |
| xd3_whole_state whole_target; |
| |
| /* statistics */ |
| xoff_t n_scpy; |
| xoff_t n_tcpy; |
| xoff_t n_add; |
| xoff_t n_run; |
| |
| xoff_t l_scpy; |
| xoff_t l_tcpy; |
| xoff_t l_add; |
| xoff_t l_run; |
| |
| usize_t i_slots_used; |
| |
| #if XD3_DEBUG |
| usize_t large_ckcnt; |
| |
| /* memory usage */ |
| usize_t alloc_cnt; |
| usize_t free_cnt; |
| #endif |
| }; |
| |
| /************************************************************************** |
| PUBLIC FUNCTIONS |
| **************************************************************************/ |
| |
| /* This function configures an xd3_stream using the provided in-memory |
| * input buffer, source buffer, output buffer, and flags. The output |
| * array must be large enough or else ENOSPC will be returned. This |
| * is the simplest in-memory encoding interface. */ |
| int xd3_encode_memory (const uint8_t *input, |
| usize_t input_size, |
| const uint8_t *source, |
| usize_t source_size, |
| uint8_t *output_buffer, |
| usize_t *output_size, |
| usize_t avail_output, |
| int flags); |
| |
| /* The reverse of xd3_encode_memory. */ |
| int xd3_decode_memory (const uint8_t *input, |
| usize_t input_size, |
| const uint8_t *source, |
| usize_t source_size, |
| uint8_t *output_buf, |
| usize_t *output_size, |
| usize_t avail_output, |
| int flags); |
| |
| /* This function encodes an in-memory input using a pre-configured |
| * xd3_stream. This allows the caller to set a variety of options |
| * which are not available in the xd3_encode/decode_memory() |
| * functions. |
| * |
| * The output array must be large enough to hold the output or else |
| * ENOSPC is returned. The source (if any) should be set using |
| * xd3_set_source_and_size() with a single-block xd3_source. This |
| * calls the underlying non-blocking interfaces, |
| * xd3_encode/decode_input(), handling the necessary input/output |
| * states. This method may be considered a reference for any |
| * application using xd3_encode_input() directly. |
| * |
| * xd3_stream stream; |
| * xd3_config config; |
| * xd3_source src; |
| * |
| * memset (& src, 0, sizeof (src)); |
| * memset (& stream, 0, sizeof (stream)); |
| * memset (& config, 0, sizeof (config)); |
| * |
| * if (source != NULL) |
| * { |
| * src.size = source_size; |
| * src.blksize = source_size; |
| * src.curblkno = 0; |
| * src.onblk = source_size; |
| * src.curblk = source; |
| * src.max_winsize = source_size; |
| * xd3_set_source(&stream, &src); |
| * } |
| * |
| * config.flags = flags; |
| * config.winsize = input_size; |
| * |
| * ... set smatcher, appheader, encoding-table, compression-level, etc. |
| * |
| * xd3_config_stream(&stream, &config); |
| * xd3_encode_stream(&stream, ...); |
| * xd3_free_stream(&stream); |
| */ |
| int xd3_encode_stream (xd3_stream *stream, |
| const uint8_t *input, |
| usize_t input_size, |
| uint8_t *output, |
| usize_t *output_size, |
| usize_t avail_output); |
| |
| /* The reverse of xd3_encode_stream. */ |
| int xd3_decode_stream (xd3_stream *stream, |
| const uint8_t *input, |
| usize_t input_size, |
| uint8_t *output, |
| usize_t *output_size, |
| usize_t avail_size); |
| |
| /* This is the non-blocking interface. |
| * |
| * Handling input and output states is the same for encoding or |
| * decoding using the xd3_avail_input() and xd3_consume_output() |
| * routines, inlined below. |
| * |
| * Return values: |
| * |
| * XD3_INPUT: the process requires more input: call |
| * xd3_avail_input() then repeat |
| * |
| * XD3_OUTPUT: the process has more output: read stream->next_out, |
| * stream->avail_out, then call xd3_consume_output(), |
| * then repeat |
| * |
| * XD3_GOTHEADER: (decoder-only) notification returned following the |
| * VCDIFF header and first window header. the decoder |
| * may use the header to configure itself. |
| * |
| * XD3_WINSTART: a general notification returned once for each |
| * window except the 0-th window, which is implied by |
| * XD3_GOTHEADER. It is recommended to use a |
| * switch-stmt such as: |
| * |
| * ... |
| * again: |
| * switch ((ret = xd3_decode_input (stream))) { |
| * case XD3_GOTHEADER: { |
| * assert(stream->current_window == 0); |
| * stuff; |
| * } |
| * // fallthrough |
| * case XD3_WINSTART: { |
| * something(stream->current_window); |
| * goto again; |
| * } |
| * ... |
| * |
| * XD3_WINFINISH: a general notification, following the complete |
| * input & output of a window. at this point, |
| * stream->total_in and stream->total_out are consistent |
| * for either encoding or decoding. |
| * |
| * XD3_GETSRCBLK: If the xd3_getblk() callback is NULL, this value |
| * is returned to initiate a non-blocking source read. |
| */ |
| int xd3_decode_input (xd3_stream *stream); |
| int xd3_encode_input (xd3_stream *stream); |
| |
| /* The xd3_config structure is used to initialize a stream - all data |
| * is copied into stream so config may be a temporary variable. See |
| * the [documentation] or comments on the xd3_config structure. */ |
| int xd3_config_stream (xd3_stream *stream, |
| xd3_config *config); |
| |
| /* Since Xdelta3 doesn't open any files, xd3_close_stream is just an |
| * error check that the stream is in a proper state to be closed: this |
| * means the encoder is flushed and the decoder is at a window |
| * boundary. The application is responsible for freeing any of the |
| * resources it supplied. */ |
| int xd3_close_stream (xd3_stream *stream); |
| |
| /* This arranges for closes the stream to succeed. Does not free the |
| * stream.*/ |
| void xd3_abort_stream (xd3_stream *stream); |
| |
| /* xd3_free_stream frees all memory allocated for the stream. The |
| * application is responsible for freeing any of the resources it |
| * supplied. */ |
| void xd3_free_stream (xd3_stream *stream); |
| |
| /* This function informs the encoder or decoder that source matching |
| * (i.e., delta-compression) is possible. For encoding, this should |
| * be called before the first xd3_encode_input. A NULL source is |
| * ignored. For decoding, this should be called before the first |
| * window is decoded, but the appheader may be read first |
| * (XD3_GOTHEADER). After decoding the header, call xd3_set_source() |
| * if you have a source file. Note: if (stream->dec_win_ind & VCD_SOURCE) |
| * is true, it means the first window expects there to be a source file. |
| */ |
| int xd3_set_source (xd3_stream *stream, |
| xd3_source *source); |
| |
| /* If the source size is known, call this instead of xd3_set_source(). |
| * to avoid having stream->getblk called (and/or to avoid XD3_GETSRCBLK). |
| * |
| * Follow these steps: |
| xd3_source source; |
| memset(&source, 0, sizeof(source)); |
| source.blksize = size; |
| source.onblk = size; |
| source.curblk = buf; |
| source.curblkno = 0; |
| int ret = xd3_set_source_and_size(&stream, &source, size); |
| ... |
| */ |
| int xd3_set_source_and_size (xd3_stream *stream, |
| xd3_source *source, |
| xoff_t source_size); |
| |
| /* This should be called before the first call to xd3_encode_input() |
| * to include application-specific data in the VCDIFF header. */ |
| void xd3_set_appheader (xd3_stream *stream, |
| const uint8_t *data, |
| usize_t size); |
| |
| /* xd3_get_appheader may be called in the decoder after XD3_GOTHEADER. |
| * For convenience, the decoder always adds a single byte padding to |
| * the end of the application header, which is set to zero in case the |
| * application header is a string. */ |
| int xd3_get_appheader (xd3_stream *stream, |
| uint8_t **data, |
| usize_t *size); |
| |
| /* To generate a VCDIFF encoded delta with xd3_encode_init() from |
| * another format, use: |
| * |
| * xd3_encode_init_partial() -- initialze encoder state (w/o hash tables) |
| * xd3_init_cache() -- reset VCDIFF address cache |
| * xd3_found_match() -- to report a copy instruction |
| * |
| * set stream->enc_state to ENC_INSTR and call xd3_encode_input as usual. |
| */ |
| int xd3_encode_init_partial (xd3_stream *stream); |
| void xd3_init_cache (xd3_addr_cache* acache); |
| int xd3_found_match (xd3_stream *stream, |
| usize_t pos, usize_t size, |
| xoff_t addr, int is_source); |
| |
| /* Gives an error string for xdelta3-speficic errors, returns NULL for |
| system errors */ |
| const char* xd3_strerror (int ret); |
| |
| /* For convenience, zero & initialize the xd3_config structure with |
| specified flags. */ |
| static inline |
| void xd3_init_config (xd3_config *config, |
| int flags) |
| { |
| memset (config, 0, sizeof (*config)); |
| config->flags = flags; |
| } |
| |
| /* This supplies some input to the stream. |
| * |
| * For encoding, if the input is larger than the configured window |
| * size (xd3_config.winsize), the entire input will be consumed and |
| * encoded anyway. If you wish to strictly limit the window size, |
| * limit the buffer passed to xd3_avail_input to the window size. |
| * |
| * For encoding, if the input is smaller than the configured window |
| * size (xd3_config.winsize), the library will create a window-sized |
| * buffer and accumulate input until a full-sized window can be |
| * encoded. XD3_INPUT will be returned. The input must remain valid |
| * until the next time xd3_encode_input() returns XD3_INPUT. |
| * |
| * For decoding, the input will be consumed entirely before XD3_INPUT |
| * is returned again. |
| */ |
| static inline |
| void xd3_avail_input (xd3_stream *stream, |
| const uint8_t *idata, |
| usize_t isize) |
| { |
| /* Even if isize is zero, the code expects a non-NULL idata. Why? |
| * It uses this value to determine whether xd3_avail_input has ever |
| * been called. If xd3_encode_input is called before |
| * xd3_avail_input it will return XD3_INPUT right away without |
| * allocating a stream->winsize buffer. This is to avoid an |
| * unwanted allocation. */ |
| XD3_ASSERT (idata != NULL || isize == 0); |
| |
| stream->next_in = idata; |
| stream->avail_in = isize; |
| } |
| |
| /* This acknowledges receipt of output data, must be called after any |
| * XD3_OUTPUT return. */ |
| static inline |
| void xd3_consume_output (xd3_stream *stream) |
| { |
| stream->avail_out = 0; |
| } |
| |
| /* These are set for each XD3_WINFINISH return. */ |
| static inline |
| int xd3_encoder_used_source (xd3_stream *stream) { |
| return stream->src != NULL && stream->src->srclen > 0; |
| } |
| static inline |
| xoff_t xd3_encoder_srcbase (xd3_stream *stream) { |
| return stream->src->srcbase; |
| } |
| static inline |
| usize_t xd3_encoder_srclen (xd3_stream *stream) { |
| return stream->src->srclen; |
| } |
| |
| /* Checks for legal flag changes. */ |
| static inline |
| void xd3_set_flags (xd3_stream *stream, int flags) |
| { |
| /* The bitwise difference should contain only XD3_FLUSH or |
| XD3_SKIP_WINDOW */ |
| XD3_ASSERT(((flags ^ stream->flags) & ~(XD3_FLUSH | XD3_SKIP_WINDOW)) == 0); |
| stream->flags = flags; |
| } |
| |
| /* Gives some extra information about the latest library error, if any |
| * is known. */ |
| static inline |
| const char* xd3_errstring (xd3_stream *stream) |
| { |
| return stream->msg ? stream->msg : ""; |
| } |
| |
| |
| /* 64-bit divisions are expensive, which is why we require a |
| * power-of-two source->blksize. To relax this restriction is |
| * relatively easy, see the history for xd3_blksize_div(). */ |
| static inline |
| void xd3_blksize_div (const xoff_t offset, |
| const xd3_source *source, |
| xoff_t *blkno, |
| usize_t *blkoff) { |
| *blkno = (xoff_t) (offset >> source->shiftby); |
| *blkoff = (usize_t) (offset & source->maskby); |
| XD3_ASSERT (*blkoff < source->blksize); |
| } |
| |
| static inline |
| void xd3_blksize_add (xoff_t *blkno, |
| usize_t *blkoff, |
| const xd3_source *source, |
| const usize_t add) |
| { |
| usize_t blkdiff; |
| |
| /* Does not check for overflow, checked in xdelta3-decode.h. */ |
| *blkoff += add; |
| blkdiff = *blkoff >> source->shiftby; |
| |
| if (blkdiff) |
| { |
| *blkno += blkdiff; |
| *blkoff &= source->maskby; |
| } |
| |
| XD3_ASSERT (*blkoff < source->blksize); |
| } |
| |
| #define XD3_NOOP 0U |
| #define XD3_ADD 1U |
| #define XD3_RUN 2U |
| #define XD3_CPY 3U /* XD3_CPY rtypes are represented as (XD3_CPY + |
| * copy-mode value) */ |
| |
| #if XD3_DEBUG |
| #define IF_DEBUG(x) x |
| #else |
| #define IF_DEBUG(x) |
| #endif |
| #if XD3_DEBUG > 1 |
| #define IF_DEBUG1(x) x |
| #else |
| #define IF_DEBUG1(x) |
| #endif |
| #if XD3_DEBUG > 2 |
| #define IF_DEBUG2(x) x |
| #else |
| #define IF_DEBUG2(x) |
| #endif |
| |
| #define SIZEOF_ARRAY(x) (sizeof(x) / sizeof(x[0])) |
| |
| #endif /* _XDELTA3_H_ */ |