X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=archival%2Fgzip.c;h=43804b2e4060fd2a0cd447e501595e6338d0df51;hb=8b814b4a349e2262c0ad25793b05206a14651ebb;hp=dcbcae0b3191d03c5bae976307690a226cddc8ef;hpb=ed0f6db35e02ccd0d8c22337639463a05e3efea1;p=oweals%2Fbusybox.git diff --git a/archival/gzip.c b/archival/gzip.c index dcbcae0b3..43804b2e4 100644 --- a/archival/gzip.c +++ b/archival/gzip.c @@ -5,9 +5,9 @@ * Based on GNU gzip Copyright (C) 1992-1993 Jean-loup Gailly. * * Originally adjusted for busybox by Charles P. Wright - * "this is a stripped down version of gzip I put into busybox, it does - * only standard in to standard out with -9 compression. It also requires - * the zcat module for some important functions." + * "this is a stripped down version of gzip I put into busybox, it does + * only standard in to standard out with -9 compression. It also requires + * the zcat module for some important functions." * * Adjusted further by Erik Andersen to support * files as well as stdin/stdout, and to generally behave itself wrt @@ -16,23 +16,57 @@ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ +/* big objects in bss: + * 00000020 b bl_count + * 00000074 b base_length + * 00000078 b base_dist + * 00000078 b static_dtree + * 0000009c b bl_tree + * 000000f4 b dyn_dtree + * 00000100 b length_code + * 00000200 b dist_code + * 0000023d b depth + * 00000400 b flag_buf + * 0000047a b heap + * 00000480 b static_ltree + * 000008f4 b dyn_ltree + */ + /* TODO: full support for -v for DESKTOP -/usr/bin/gzip -v a bogus aa + * "/usr/bin/gzip -v a bogus aa" should say: a: 85.1% -- replaced with a.gz gzip: bogus: No such file or directory aa: 85.1% -- replaced with aa.gz */ -#define SMALL_MEM +#include "libbb.h" +#include "unarchive.h" + + +/* =========================================================================== + */ +//#define DEBUG 1 +/* Diagnostic functions */ +#ifdef DEBUG +# define Assert(cond,msg) { if (!(cond)) bb_error_msg(msg); } +# define Trace(x) fprintf x +# define Tracev(x) {if (verbose) fprintf x; } +# define Tracevv(x) {if (verbose > 1) fprintf x; } +# define Tracec(c,x) {if (verbose && (c)) fprintf x; } +# define Tracecv(c,x) {if (verbose > 1 && (c)) fprintf x; } +#else +# define Assert(cond,msg) +# define Trace(x) +# define Tracev(x) +# define Tracevv(x) +# define Tracec(c,x) +# define Tracecv(c,x) +#endif -//#include -#include "busybox.h" -/* Compression methods (see algorithm.doc) */ -/* Only STORED and DEFLATED are supported by this BusyBox module */ -#define STORED 0 -/* methods 4 to 7 reserved */ -#define DEFLATED 8 +/* =========================================================================== + */ +#define SMALL_MEM #ifndef INBUFSIZ # ifdef SMALL_MEM @@ -42,8 +76,6 @@ aa: 85.1% -- replaced with aa.gz # endif #endif -#define INBUF_EXTRA 64 /* required by unlzw() */ - #ifndef OUTBUFSIZ # ifdef SMALL_MEM # define OUTBUFSIZ 8192 /* output buffer size */ @@ -51,7 +83,6 @@ aa: 85.1% -- replaced with aa.gz # define OUTBUFSIZ 16384 /* output buffer size */ # endif #endif -#define OUTBUF_EXTRA 2048 /* required by unlzw() */ #ifndef DIST_BUFSIZE # ifdef SMALL_MEM @@ -61,12 +92,6 @@ aa: 85.1% -- replaced with aa.gz # endif #endif -#define PACK_MAGIC "\037\036" /* Magic header for packed files */ -#define GZIP_MAGIC "\037\213" /* Magic header for gzip files, 1F 8B */ -#define OLD_GZIP_MAGIC "\037\236" /* Magic header for gzip 0.5 = freeze 1.x */ -#define LZH_MAGIC "\037\240" /* Magic header for SCO LZH Compress files */ -#define PKZIP_MAGIC "\120\113\003\004" /* Magic header for pkzip files */ - /* gzip flag byte */ #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ @@ -127,123 +152,200 @@ aa: 85.1% -- replaced with aa.gz #endif -#define DECLARE(type, array, size)\ - static type * array -#define ALLOC(type, array, size) { \ - array = xzalloc((size_t)(((size)+1L)/2) * 2*sizeof(type)); \ -} -#define FREE(array) { \ - free(array); \ - array = NULL; \ -} +/* =========================================================================== + * Compile with MEDIUM_MEM to reduce the memory requirements or + * with SMALL_MEM to use as little memory as possible. Use BIG_MEM if the + * entire input file can be held in memory (not possible on 16 bit systems). + * Warning: defining these symbols affects HASH_BITS (see below) and thus + * affects the compression ratio. The compressed output + * is still correct, and might even be smaller in some cases. + */ -/* Diagnostic functions */ -#ifdef DEBUG -# define Assert(cond,msg) {if(!(cond)) bb_error_msg(msg);} -# define Trace(x) fprintf x -# define Tracev(x) {if (verbose) fprintf x ;} -# define Tracevv(x) {if (verbose>1) fprintf x ;} -# define Tracec(c,x) {if (verbose && (c)) fprintf x ;} -# define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} -#else -# define Assert(cond,msg) -# define Trace(x) -# define Tracev(x) -# define Tracevv(x) -# define Tracec(c,x) -# define Tracecv(c,x) +#ifdef SMALL_MEM +# define HASH_BITS 13 /* Number of bits used to hash strings */ +#endif +#ifdef MEDIUM_MEM +# define HASH_BITS 14 +#endif +#ifndef HASH_BITS +# define HASH_BITS 15 + /* For portability to 16 bit machines, do not use values above 15. */ +#endif + +#define HASH_SIZE (unsigned)(1<= 4. + */ + + max_insert_length = max_lazy_match, +/* Insert new strings in the hash table only if the match length + * is not greater than this length. This saves time but degrades compression. + * max_insert_length is used only for compression levels <= 3. + */ + + good_match = 32, +/* Use a faster search when the previous match is longer than this */ + +/* Values for max_lazy_match, good_match and max_chain_length, depending on + * the desired pack level (0..9). The values given below have been tuned to + * exclude worst case performance for pathological files. Better values may be + * found for specific files. + */ + + nice_match = 258, /* Stop searching when current match exceeds this */ +/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 + * For deflate_fast() (levels <= 3) good is ignored and lazy has a different + * meaning. + */ +}; + + +struct globals { + lng block_start; -/* from zip.c: */ -static int zip(int in, int out); -static unsigned file_read(void *buf, unsigned size); +/* window position at the beginning of the current output block. Gets + * negative when the window is moved backwards. + */ + unsigned ins_h; /* hash index of string to be inserted */ -/* from deflate.c */ -static void lm_init(ush * flags); -static ulg deflate(void); +#define H_SHIFT ((HASH_BITS+MIN_MATCH-1) / MIN_MATCH) +/* Number of bits by which ins_h and del_h must be shifted at each + * input step. It must be such that after MIN_MATCH steps, the oldest + * byte no longer takes part in the hash key, that is: + * H_SHIFT * MIN_MATCH >= HASH_BITS + */ -/* from trees.c */ -static void ct_init(ush * attr, int *methodp); -static int ct_tally(int dist, int lc); -static ulg flush_block(char *buf, ulg stored_len, int eof); + unsigned prev_length; -/* from bits.c */ -static void bi_init(int zipfile); -static void send_bits(int value, int length); -static unsigned bi_reverse(unsigned value, int length); -static void bi_windup(void); -static void copy_block(char *buf, unsigned len, int header); +/* Length of the best match at previous step. Matches not greater than this + * are discarded. This is used in the lazy match evaluation. + */ -/* global buffers */ + unsigned strstart; /* start of string to insert */ + unsigned match_start; /* start of matching string */ + unsigned lookahead; /* number of valid bytes ahead in window */ -/* To save memory for 16 bit systems, some arrays are overlaid between - * the various modules: - * deflate: prev+head window d_buf l_buf outbuf - * unlzw: tab_prefix tab_suffix stack inbuf outbuf - * For compression, input is done in window[]. For decompression, output - * is done in window except for unlzw. +/* =========================================================================== */ +#define DECLARE(type, array, size) \ + type * array +#define ALLOC(type, array, size) \ + array = xzalloc((size_t)(((size)+1L)/2) * 2*sizeof(type)); +#define FREE(array) \ + do { free(array); array = NULL; } while (0) + /* global buffers */ + + /* buffer for literals or lengths */ + /* DECLARE(uch, l_buf, LIT_BUFSIZE); */ + DECLARE(uch, l_buf, INBUFSIZ); + + DECLARE(ush, d_buf, DIST_BUFSIZE); + DECLARE(uch, outbuf, OUTBUFSIZ); + +/* Sliding window. Input bytes are read into the second half of the window, + * and move to the first half later to keep a dictionary of at least WSIZE + * bytes. With this organization, matches are limited to a distance of + * WSIZE-MAX_MATCH bytes, but this ensures that IO is always + * performed with a length multiple of the block size. Also, it limits + * the window size to 64K, which is quite useful on MSDOS. + * To do: limit the window size to WSIZE+BSZ if SMALL_MEM (the code would + * be less efficient). + */ + DECLARE(uch, window, 2L * WSIZE); -#define tab_suffix window -#define tab_prefix prev /* hash link (see deflate.c) */ -#define head (prev+WSIZE) /* hash head (see deflate.c) */ +/* Link to older string with same hash index. To limit the size of this + * array to 64K, this link is maintained only for the last 32K strings. + * An index in this array is thus a window index modulo 32K. + */ + /* DECLARE(Pos, prev, WSIZE); */ + DECLARE(ush, prev, 1L << BITS); -DECLARE(uch, inbuf, INBUFSIZ + INBUF_EXTRA); -DECLARE(uch, outbuf, OUTBUFSIZ + OUTBUF_EXTRA); -DECLARE(ush, d_buf, DIST_BUFSIZE); -DECLARE(uch, window, 2L * WSIZE); -DECLARE(ush, tab_prefix, 1L << BITS); +/* Heads of the hash chains or 0. */ + /* DECLARE(Pos, head, 1<> 8; + if (G1.outcnt < OUTBUFSIZ - 2) { + G1.outbuf[G1.outcnt++] = w; + G1.outbuf[G1.outcnt++] = w >> 8; } else { put_8bit(w); put_8bit(w >> 8); @@ -286,25 +388,16 @@ static void put_32bit(ulg n) put_16bit(n >> 16); } -/* put_header_byte is used for the compressed output - * - for the initial 4 bytes that can't overflow the buffer. - */ -#define put_header_byte(c) \ -{ \ - outbuf[outcnt++] = (c); \ -} - - /* =========================================================================== * Clear input and output buffers */ static void clear_bufs(void) { - outcnt = 0; + G1.outcnt = 0; #ifdef DEBUG - insize = 0; + G1.insize = 0; #endif - isize = 0L; + G1.isize = 0; } @@ -313,21 +406,14 @@ static void clear_bufs(void) * pointer, then initialize the crc shift register contents instead. * Return the current crc in either case. */ -static uint32_t crc = ~0; /* shift register contents */ static uint32_t updcrc(uch * s, unsigned n) { - uint32_t c; /* temporary variable */ - - if (s == NULL) { - c = ~0; - } else { - c = crc; - while (n) { - c = crc_32_tab[(uch)(c ^ *s++)] ^ (c >> 8); - n--; - } + uint32_t c = G1.crc; + while (n) { + c = G1.crc_32_tab[(uch)(c ^ *s++)] ^ (c >> 8); + n--; } - crc = c; + G1.crc = c; return c; } @@ -341,32 +427,18 @@ static unsigned file_read(void *buf, unsigned size) { unsigned len; - Assert(insize == 0, "inbuf not empty"); + Assert(G1.insize == 0, "l_buf not empty"); len = safe_read(ifd, buf, size); if (len == (unsigned)(-1) || len == 0) return len; updcrc(buf, len); - isize += len; + G1.isize += len; return len; } -/* =========================================================================== - * Initialize the bit string routines. - */ -static void bi_init(int zipfile) -{ - zfile = zipfile; - bi_buf = 0; - bi_valid = 0; -#ifdef DEBUG - bits_sent = 0L; -#endif -} - - /* =========================================================================== * Send a value on a given number of bits. * IN assertion: length <= 16 and value fits in length bits. @@ -376,23 +448,24 @@ static void send_bits(int value, int length) #ifdef DEBUG Tracev((stderr, " l %2d v %4x ", length, value)); Assert(length > 0 && length <= 15, "invalid length"); - bits_sent += length; + G1.bits_sent += length; #endif /* If not enough room in bi_buf, use (valid) bits from bi_buf and * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) * unused bits in value. */ - if (bi_valid > (int) BUF_SIZE - length) { - bi_buf |= (value << bi_valid); - put_16bit(bi_buf); - bi_buf = (ush) value >> (BUF_SIZE - bi_valid); - bi_valid += length - BUF_SIZE; + if (G1.bi_valid > (int) BUF_SIZE - length) { + G1.bi_buf |= (value << G1.bi_valid); + put_16bit(G1.bi_buf); + G1.bi_buf = (ush) value >> (BUF_SIZE - G1.bi_valid); + G1.bi_valid += length - BUF_SIZE; } else { - bi_buf |= value << bi_valid; - bi_valid += length; + G1.bi_buf |= value << G1.bi_valid; + G1.bi_valid += length; } } + /* =========================================================================== * Reverse the first len bits of a code, using straightforward code (a faster * method would use a table) @@ -402,30 +475,33 @@ static unsigned bi_reverse(unsigned code, int len) { unsigned res = 0; - do { + while (1) { res |= code & 1; - code >>= 1, res <<= 1; - } while (--len > 0); - return res >> 1; + if (--len <= 0) return res; + code >>= 1; + res <<= 1; + } } + /* =========================================================================== * Write out any remaining bits in an incomplete byte. */ static void bi_windup(void) { - if (bi_valid > 8) { - put_16bit(bi_buf); - } else if (bi_valid > 0) { - put_8bit(bi_buf); + if (G1.bi_valid > 8) { + put_16bit(G1.bi_buf); + } else if (G1.bi_valid > 0) { + put_8bit(G1.bi_buf); } - bi_buf = 0; - bi_valid = 0; + G1.bi_buf = 0; + G1.bi_valid = 0; #ifdef DEBUG - bits_sent = (bits_sent + 7) & ~7; + G1.bits_sent = (G1.bits_sent + 7) & ~7; #endif } + /* =========================================================================== * Copy a stored block to the zip file, storing first the length and its * one's complement if requested. @@ -438,261 +514,101 @@ static void copy_block(char *buf, unsigned len, int header) put_16bit(len); put_16bit(~len); #ifdef DEBUG - bits_sent += 2 * 16; + G1.bits_sent += 2 * 16; #endif } #ifdef DEBUG - bits_sent += (ulg) len << 3; + G1.bits_sent += (ulg) len << 3; #endif while (len--) { put_8bit(*buf++); } } + /* =========================================================================== - * Configuration parameters + * Fill the window when the lookahead becomes insufficient. + * Updates strstart and lookahead, and sets eofile if end of input file. + * IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0 + * OUT assertions: at least one byte has been read, or eofile is set; + * file reads are performed for at least two bytes (required for the + * translate_eol option). */ +static void fill_window(void) +{ + unsigned n, m; + unsigned more = WINDOW_SIZE - G1.lookahead - G1.strstart; + /* Amount of free space at the end of the window. */ -/* Compile with MEDIUM_MEM to reduce the memory requirements or - * with SMALL_MEM to use as little memory as possible. Use BIG_MEM if the - * entire input file can be held in memory (not possible on 16 bit systems). - * Warning: defining these symbols affects HASH_BITS (see below) and thus - * affects the compression ratio. The compressed output - * is still correct, and might even be smaller in some cases. - */ + /* If the window is almost full and there is insufficient lookahead, + * move the upper half to the lower one to make room in the upper half. + */ + if (more == (unsigned) -1) { + /* Very unlikely, but possible on 16 bit machine if strstart == 0 + * and lookahead == 1 (input done one byte at time) + */ + more--; + } else if (G1.strstart >= WSIZE + MAX_DIST) { + /* By the IN assertion, the window is not empty so we can't confuse + * more == 0 with more == 64K on a 16 bit machine. + */ + Assert(WINDOW_SIZE == 2 * WSIZE, "no sliding with BIG_MEM"); + + memcpy(G1.window, G1.window + WSIZE, WSIZE); + G1.match_start -= WSIZE; + G1.strstart -= WSIZE; /* we now have strstart >= MAX_DIST: */ + + G1.block_start -= WSIZE; + + for (n = 0; n < HASH_SIZE; n++) { + m = head[n]; + head[n] = (Pos) (m >= WSIZE ? m - WSIZE : 0); + } + for (n = 0; n < WSIZE; n++) { + m = G1.prev[n]; + G1.prev[n] = (Pos) (m >= WSIZE ? m - WSIZE : 0); + /* If n is not on any hash chain, prev[n] is garbage but + * its value will never be used. + */ + } + more += WSIZE; + } + /* At this point, more >= 2 */ + if (!G1.eofile) { + n = file_read(G1.window + G1.strstart + G1.lookahead, more); + if (n == 0 || n == (unsigned) -1) { + G1.eofile = 1; + } else { + G1.lookahead += n; + } + } +} -#ifdef SMALL_MEM -# define HASH_BITS 13 /* Number of bits used to hash strings */ -#endif -#ifdef MEDIUM_MEM -# define HASH_BITS 14 -#endif -#ifndef HASH_BITS -# define HASH_BITS 15 - /* For portability to 16 bit machines, do not use values above 15. */ -#endif -/* To save space (see unlzw.c), we overlay prev+head with tab_prefix and - * window with tab_suffix. Check that we can do this: - */ -#if (WSIZE<<1) > (1< BITS-1 -# error cannot overlay head with tab_prefix1 -#endif -#define HASH_SIZE (unsigned)(1<= 1 */ -typedef ush Pos; -typedef unsigned IPos; -/* A Pos is an index in the character window. We use short instead of int to - * save space in the various tables. IPos is used only for parameter passing. +/* For MSDOS, OS/2 and 386 Unix, an optimized version is in match.asm or + * match.s. The code is functionally equivalent, so you can use the C version + * if desired. */ - -/* DECLARE(uch, window, 2L*WSIZE); */ -/* Sliding window. Input bytes are read into the second half of the window, - * and move to the first half later to keep a dictionary of at least WSIZE - * bytes. With this organization, matches are limited to a distance of - * WSIZE-MAX_MATCH bytes, but this ensures that IO is always - * performed with a length multiple of the block size. Also, it limits - * the window size to 64K, which is quite useful on MSDOS. - * To do: limit the window size to WSIZE+BSZ if SMALL_MEM (the code would - * be less efficient). - */ - -/* DECLARE(Pos, prev, WSIZE); */ -/* Link to older string with same hash index. To limit the size of this - * array to 64K, this link is maintained only for the last 32K strings. - * An index in this array is thus a window index modulo 32K. - */ - -/* DECLARE(Pos, head, 1<= HASH_BITS - */ - -static unsigned int prev_length; - -/* Length of the best match at previous step. Matches not greater than this - * are discarded. This is used in the lazy match evaluation. - */ - -static unsigned strstart; /* start of string to insert */ -static unsigned match_start; /* start of matching string */ -static int eofile; /* flag set at end of input file */ -static unsigned lookahead; /* number of valid bytes ahead in window */ - -enum { - max_chain_length = 4096, - -/* To speed up deflation, hash chains are never searched beyond this length. - * A higher limit improves compression ratio but degrades the speed. - */ - - max_lazy_match = 258, - -/* Attempt to find a better match only when the current match is strictly - * smaller than this value. This mechanism is used only for compression - * levels >= 4. - */ - max_insert_length = max_lazy_match, -/* Insert new strings in the hash table only if the match length - * is not greater than this length. This saves time but degrades compression. - * max_insert_length is used only for compression levels <= 3. - */ - - good_match = 32, - -/* Use a faster search when the previous match is longer than this */ - - -/* Values for max_lazy_match, good_match and max_chain_length, depending on - * the desired pack level (0..9). The values given below have been tuned to - * exclude worst case performance for pathological files. Better values may be - * found for specific files. - */ - - nice_match = 258 /* Stop searching when current match exceeds this */ - -/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 - * For deflate_fast() (levels <= 3) good is ignored and lazy has a different - * meaning. - */ -}; - -#define EQUAL 0 -/* result of memcmp for equal strings */ - -/* =========================================================================== - * Prototypes for local functions. - */ -static void fill_window(void); - -static int longest_match(IPos cur_match); - -#ifdef DEBUG -static void check_match(IPos start, IPos match, int length); -#endif - -/* =========================================================================== - * Update a hash value with the given input byte - * IN assertion: all calls to to UPDATE_HASH are made with consecutive - * input characters, so that a running hash key can be computed from the - * previous key instead of complete recalculation each time. - */ -#define UPDATE_HASH(h,c) (h = (((h)<= 1 - */ - -/* For MSDOS, OS/2 and 386 Unix, an optimized version is in match.asm or - * match.s. The code is functionally equivalent, so you can use the C version - * if desired. - */ -static int longest_match(IPos cur_match) -{ - unsigned chain_length = max_chain_length; /* max hash chain length */ - uch *scan = window + strstart; /* current string */ - uch *match; /* matched string */ - int len; /* length of current match */ - int best_len = prev_length; /* best match length so far */ - IPos limit = strstart > (IPos) MAX_DIST ? strstart - (IPos) MAX_DIST : 0; - /* Stop when cur_match becomes <= limit. To simplify the code, - * we prevent matches with the string of window index 0. - */ +static int longest_match(IPos cur_match) +{ + unsigned chain_length = max_chain_length; /* max hash chain length */ + uch *scan = G1.window + G1.strstart; /* current string */ + uch *match; /* matched string */ + int len; /* length of current match */ + int best_len = G1.prev_length; /* best match length so far */ + IPos limit = G1.strstart > (IPos) MAX_DIST ? G1.strstart - (IPos) MAX_DIST : 0; + /* Stop when cur_match becomes <= limit. To simplify the code, + * we prevent matches with the string of window index 0. + */ /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. * It is easy to get rid of this optimization if necessary. @@ -700,19 +616,19 @@ static int longest_match(IPos cur_match) #if HASH_BITS < 8 || MAX_MATCH != 258 # error Code too clever #endif - uch *strend = window + strstart + MAX_MATCH; + uch *strend = G1.window + G1.strstart + MAX_MATCH; uch scan_end1 = scan[best_len - 1]; uch scan_end = scan[best_len]; /* Do not waste too much time if we already have a good match: */ - if (prev_length >= good_match) { + if (G1.prev_length >= good_match) { chain_length >>= 2; } - Assert(strstart <= window_size - MIN_LOOKAHEAD, "insufficient lookahead"); + Assert(G1.strstart <= WINDOW_SIZE - MIN_LOOKAHEAD, "insufficient lookahead"); do { - Assert(cur_match < strstart, "no future"); - match = window + cur_match; + Assert(cur_match < G1.strstart, "no future"); + match = G1.window + cur_match; /* Skip to next match if the match length cannot increase * or if the match length is less than 2: @@ -743,19 +659,20 @@ static int longest_match(IPos cur_match) scan = strend - MAX_MATCH; if (len > best_len) { - match_start = cur_match; + G1.match_start = cur_match; best_len = len; if (len >= nice_match) break; scan_end1 = scan[best_len - 1]; scan_end = scan[best_len]; } - } while ((cur_match = prev[cur_match & WMASK]) > limit + } while ((cur_match = G1.prev[cur_match & WMASK]) > limit && --chain_length != 0); return best_len; } + #ifdef DEBUG /* =========================================================================== * Check that the match at match_start is indeed a match. @@ -763,345 +680,21 @@ static int longest_match(IPos cur_match) static void check_match(IPos start, IPos match, int length) { /* check that the match is indeed a match */ - if (memcmp(window + match, window + start, length) != EQUAL) { + if (memcmp(G1.window + match, G1.window + start, length) != 0) { bb_error_msg(" start %d, match %d, length %d", start, match, length); bb_error_msg("invalid match"); } if (verbose > 1) { bb_error_msg("\\[%d,%d]", start - match, length); do { - putc(window[start++], stderr); + fputc(G1.window[start++], stderr); } while (--length != 0); } } #else -# define check_match(start, match, length) -#endif - -/* =========================================================================== - * Fill the window when the lookahead becomes insufficient. - * Updates strstart and lookahead, and sets eofile if end of input file. - * IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0 - * OUT assertions: at least one byte has been read, or eofile is set; - * file reads are performed for at least two bytes (required for the - * translate_eol option). - */ -static void fill_window(void) -{ - unsigned n, m; - unsigned more = window_size - lookahead - strstart; - /* Amount of free space at the end of the window. */ - - /* If the window is almost full and there is insufficient lookahead, - * move the upper half to the lower one to make room in the upper half. - */ - if (more == (unsigned) -1) { - /* Very unlikely, but possible on 16 bit machine if strstart == 0 - * and lookahead == 1 (input done one byte at time) - */ - more--; - } else if (strstart >= WSIZE + MAX_DIST) { - /* By the IN assertion, the window is not empty so we can't confuse - * more == 0 with more == 64K on a 16 bit machine. - */ - Assert(window_size == (ulg) 2 * WSIZE, "no sliding with BIG_MEM"); - - memcpy(window, window + WSIZE, WSIZE); - match_start -= WSIZE; - strstart -= WSIZE; /* we now have strstart >= MAX_DIST: */ - - block_start -= (long) WSIZE; - - for (n = 0; n < HASH_SIZE; n++) { - m = head[n]; - head[n] = (Pos) (m >= WSIZE ? m - WSIZE : NIL); - } - for (n = 0; n < WSIZE; n++) { - m = prev[n]; - prev[n] = (Pos) (m >= WSIZE ? m - WSIZE : NIL); - /* If n is not on any hash chain, prev[n] is garbage but - * its value will never be used. - */ - } - more += WSIZE; - } - /* At this point, more >= 2 */ - if (!eofile) { - n = file_read(window + strstart + lookahead, more); - if (n == 0 || n == (unsigned) -1) { - eofile = 1; - } else { - lookahead += n; - } - } -} - -/* =========================================================================== - * Flush the current block, with given end-of-file flag. - * IN assertion: strstart is set to the end of the current match. - */ -#define FLUSH_BLOCK(eof) \ - flush_block(block_start >= 0L \ - ? (char*)&window[(unsigned)block_start] \ - : (char*)NULL, \ - (long)strstart - block_start, (eof)) - -/* =========================================================================== - * Same as above, but achieves better compression. We use a lazy - * evaluation for matches: a match is finally adopted only if there is - * no better match at the next window position. - * - * Processes a new input file and return its compressed length. Sets - * the compressed length, crc, deflate flags and internal file - * attributes. - */ -static ulg deflate(void) -{ - IPos hash_head; /* head of hash chain */ - IPos prev_match; /* previous match */ - int flush; /* set if current block must be flushed */ - int match_available = 0; /* set if previous match exists */ - unsigned match_length = MIN_MATCH - 1; /* length of best match */ - - /* Process the input block. */ - while (lookahead != 0) { - /* Insert the string window[strstart .. strstart+2] in the - * dictionary, and set hash_head to the head of the hash chain: - */ - INSERT_STRING(strstart, hash_head); - - /* Find the longest match, discarding those <= prev_length. - */ - prev_length = match_length, prev_match = match_start; - match_length = MIN_MATCH - 1; - - if (hash_head != 0 && prev_length < max_lazy_match - && strstart - hash_head <= MAX_DIST - ) { - /* To simplify the code, we prevent matches with the string - * of window index 0 (in particular we have to avoid a match - * of the string with itself at the start of the input file). - */ - match_length = longest_match(hash_head); - /* longest_match() sets match_start */ - if (match_length > lookahead) - match_length = lookahead; - - /* Ignore a length 3 match if it is too distant: */ - if (match_length == MIN_MATCH && strstart - match_start > TOO_FAR) { - /* If prev_match is also MIN_MATCH, match_start is garbage - * but we will ignore the current match anyway. - */ - match_length--; - } - } - /* If there was a match at the previous step and the current - * match is not better, output the previous match: - */ - if (prev_length >= MIN_MATCH && match_length <= prev_length) { - - check_match(strstart - 1, prev_match, prev_length); - - flush = ct_tally(strstart - 1 - prev_match, prev_length - MIN_MATCH); - - /* Insert in hash table all strings up to the end of the match. - * strstart-1 and strstart are already inserted. - */ - lookahead -= prev_length - 1; - prev_length -= 2; - do { - strstart++; - INSERT_STRING(strstart, hash_head); - /* strstart never exceeds WSIZE-MAX_MATCH, so there are - * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH - * these bytes are garbage, but it does not matter since the - * next lookahead bytes will always be emitted as literals. - */ - } while (--prev_length != 0); - match_available = 0; - match_length = MIN_MATCH - 1; - strstart++; - if (flush) - FLUSH_BLOCK(0), block_start = strstart; - } else if (match_available) { - /* If there was no match at the previous position, output a - * single literal. If there was a match but the current match - * is longer, truncate the previous match to a single literal. - */ - Tracevv((stderr, "%c", window[strstart - 1])); - if (ct_tally(0, window[strstart - 1])) { - FLUSH_BLOCK(0), block_start = strstart; - } - strstart++; - lookahead--; - } else { - /* There is no previous match to compare with, wait for - * the next step to decide. - */ - match_available = 1; - strstart++; - lookahead--; - } - Assert(strstart <= isize && lookahead <= isize, "a bit too far"); - - /* Make sure that we always have enough lookahead, except - * at the end of the input file. We need MAX_MATCH bytes - * for the next match, plus MIN_MATCH bytes to insert the - * string following the next match. - */ - while (lookahead < MIN_LOOKAHEAD && !eofile) - fill_window(); - } - if (match_available) - ct_tally(0, window[strstart - 1]); - - return FLUSH_BLOCK(1); /* eof */ -} - - -/* ======================================================================== */ -static void abort_gzip(int ATTRIBUTE_UNUSED ignored) -{ - exit(1); -} - -int gzip_main(int argc, char **argv) -{ - enum { - OPT_tostdout = 0x1, - OPT_force = 0x2, - }; - - unsigned opt; - int result; - int inFileNum; - int outFileNum; - struct stat statBuf; - char *delFileName; - - opt = getopt32(argc, argv, "cf123456789qv" USE_GUNZIP("d")); - //if (opt & 0x1) // -c - //if (opt & 0x2) // -f - /* Ignore 1-9 (compression level) options */ - //if (opt & 0x4) // -1 - //if (opt & 0x8) // -2 - //if (opt & 0x10) // -3 - //if (opt & 0x20) // -4 - //if (opt & 0x40) // -5 - //if (opt & 0x80) // -6 - //if (opt & 0x100) // -7 - //if (opt & 0x200) // -8 - //if (opt & 0x400) // -9 - //if (opt & 0x800) // -q - //if (opt & 0x1000) // -v -#if ENABLE_GUNZIP /* gunzip_main may not be visible... */ - if (opt & 0x2000) { // -d - /* FIXME: getopt32 should not depend on optind */ - optind = 1; - return gunzip_main(argc, argv); - } -#endif - - foreground = signal(SIGINT, SIG_IGN) != SIG_IGN; - if (foreground) { - (void) signal(SIGINT, abort_gzip); - } -#ifdef SIGTERM - if (signal(SIGTERM, SIG_IGN) != SIG_IGN) { - (void) signal(SIGTERM, abort_gzip); - } -#endif -#ifdef SIGHUP - if (signal(SIGHUP, SIG_IGN) != SIG_IGN) { - (void) signal(SIGHUP, abort_gzip); - } -#endif - - strncpy(z_suffix, ".gz", sizeof(z_suffix) - 1); - - /* Allocate all global buffers (for DYN_ALLOC option) */ - ALLOC(uch, inbuf, INBUFSIZ + INBUF_EXTRA); - ALLOC(uch, outbuf, OUTBUFSIZ + OUTBUF_EXTRA); - ALLOC(ush, d_buf, DIST_BUFSIZE); - ALLOC(uch, window, 2L * WSIZE); - ALLOC(ush, tab_prefix, 1L << BITS); - - /* Initialise the CRC32 table */ - crc_32_tab = crc32_filltable(0); - - clear_bufs(); - - if (optind == argc) { - time_stamp = 0; - zip(STDIN_FILENO, STDOUT_FILENO); - } else { - int i; - - for (i = optind; i < argc; i++) { - char *path = NULL; - - clear_bufs(); - if (LONE_DASH(argv[i])) { - time_stamp = 0; - inFileNum = STDIN_FILENO; - outFileNum = STDOUT_FILENO; - } else { - inFileNum = xopen(argv[i], O_RDONLY); - if (fstat(inFileNum, &statBuf) < 0) - bb_perror_msg_and_die("%s", argv[i]); - time_stamp = statBuf.st_ctime; - - if (!(opt & OPT_tostdout)) { - path = xasprintf("%s.gz", argv[i]); - - /* Open output file */ -#if defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1 && defined(O_NOFOLLOW) - outFileNum = - open(path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW); -#else - outFileNum = open(path, O_RDWR | O_CREAT | O_EXCL); +# define check_match(start, match, length) ((void)0) #endif - if (outFileNum < 0) { - bb_perror_msg("%s", path); - free(path); - continue; - } - - /* Set permissions on the file */ - fchmod(outFileNum, statBuf.st_mode); - } else - outFileNum = STDOUT_FILENO; - } - - if (path == NULL && isatty(outFileNum) && !(opt & OPT_force)) { - bb_error_msg - ("compressed data not written to a terminal. Use -f to force compression."); - free(path); - continue; - } - - result = zip(inFileNum, outFileNum); - - if (path != NULL) { - close(inFileNum); - close(outFileNum); - - /* Delete the original file */ - if (result == 0) - delFileName = argv[i]; - else - delFileName = path; - if (unlink(delFileName) < 0) - bb_perror_msg("%s", delFileName); - } - - free(path); - } - } - - return exit_code; -} /* trees.c -- output deflated data using Huffman coding * Copyright (C) 1992-1993 Jean-loup Gailly @@ -1109,14 +702,11 @@ int gzip_main(int argc, char **argv) * terms of the GNU General Public License, see the file COPYING. */ -/* - * PURPOSE - * +/* PURPOSE * Encode various sets of source values using variable-length * binary code trees. * * DISCUSSION - * * The PKZIP "deflation" process uses several Huffman trees. The more * common source values are represented by shorter bit sequences. * @@ -1128,7 +718,6 @@ int gzip_main(int argc, char **argv) * (APPNOTE.TXT) distributed as part of PKWARE's PKZIP program. * * REFERENCES - * * Lynch, Thomas J. * Data Compression: Techniques and Applications, pp. 53-55. * Lifetime Learning Publications, 1985. ISBN 0-534-03418-7. @@ -1142,24 +731,18 @@ int gzip_main(int argc, char **argv) * Addison-Wesley, 1983. ISBN 0-201-06672-6. * * INTERFACE - * - * void ct_init(ush *attr, int *methodp) - * Allocate the match buffer, initialize the various tables and save + * void ct_init() + * Allocate the match buffer, initialize the various tables [and save * the location of the internal file attribute (ascii/binary) and - * method (DEFLATE/STORE) + * method (DEFLATE/STORE) -- deleted in bbox] * * void ct_tally(int dist, int lc); * Save the match info and tally the frequency counts. * - * long flush_block (char *buf, ulg stored_len, int eof) + * ulg flush_block(char *buf, ulg stored_len, int eof) * Determine the best encoding for the current block: dynamic trees, * static trees or store, and output the encoded block to the zip * file. Returns the total compressed length for the file so far. - * - */ - -/* =========================================================================== - * Constants */ #define MAX_BITS 15 @@ -1186,23 +769,25 @@ int gzip_main(int argc, char **argv) #define BL_CODES 19 /* number of codes used to transfer the bit lengths */ -typedef uch extra_bits_t; - /* extra bits for each length code */ -static const extra_bits_t extra_lbits[LENGTH_CODES] - = { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, +static const uint8_t extra_lbits[LENGTH_CODES] ALIGN1 = { + 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0 }; /* extra bits for each distance code */ -static const extra_bits_t extra_dbits[D_CODES] - = { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, +static const uint8_t extra_dbits[D_CODES] ALIGN1 = { + 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13 }; /* extra bits for each bit length code */ -static const extra_bits_t extra_blbits[BL_CODES] -= { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 7 }; +static const uint8_t extra_blbits[BL_CODES] ALIGN1 = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 7 }; + +/* number of codes at each bit length for an optimal tree */ +static const uint8_t bl_order[BL_CODES] ALIGN1 = { + 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 }; #define STORED_BLOCK 0 #define STATIC_TREES 1 @@ -1243,9 +828,6 @@ static const extra_bits_t extra_blbits[BL_CODES] * memory at the expense of compression). Some optimizations would be possible * if we rely on DIST_BUFSIZE == LIT_BUFSIZE. */ -#if LIT_BUFSIZE > INBUFSIZ -#error cannot overlay l_buf and inbuf -#endif #define REP_3_6 16 /* repeat previous bit length 3-6 times (2 bits of repeat count) */ #define REPZ_3_10 17 @@ -1254,9 +836,7 @@ static const extra_bits_t extra_blbits[BL_CODES] /* repeat a zero length 11-138 times (7 bits of repeat count) */ /* =========================================================================== - * Local data - */ - +*/ /* Data structure describing a single value and its code string. */ typedef struct ct_data { union { @@ -1274,13 +854,33 @@ typedef struct ct_data { #define Dad dl.dad #define Len dl.len -#define HEAP_SIZE (2*L_CODES+1) +#define HEAP_SIZE (2*L_CODES + 1) /* maximum heap size */ -static ct_data dyn_ltree[HEAP_SIZE]; /* literal and length tree */ -static ct_data dyn_dtree[2 * D_CODES + 1]; /* distance tree */ +typedef struct tree_desc { + ct_data *dyn_tree; /* the dynamic tree */ + ct_data *static_tree; /* corresponding static tree or NULL */ + const uint8_t *extra_bits; /* extra bits for each code or NULL */ + int extra_base; /* base index for extra_bits */ + int elems; /* max number of elements in the tree */ + int max_length; /* max bit length for the codes */ + int max_code; /* largest code with non zero frequency */ +} tree_desc; + +struct globals2 { + + ush heap[HEAP_SIZE]; /* heap used to build the Huffman trees */ + int heap_len; /* number of elements in the heap */ + int heap_max; /* element of largest frequency */ -static ct_data static_ltree[L_CODES + 2]; +/* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. + * The same heap array is used to build all trees. + */ + + ct_data dyn_ltree[HEAP_SIZE]; /* literal and length tree */ + ct_data dyn_dtree[2 * D_CODES + 1]; /* distance tree */ + + ct_data static_ltree[L_CODES + 2]; /* The static literal tree. Since the bit lengths are imposed, there is no * need for the L_CODES extra codes used during heap construction. However @@ -1288,121 +888,78 @@ static ct_data static_ltree[L_CODES + 2]; * below). */ -static ct_data static_dtree[D_CODES]; + ct_data static_dtree[D_CODES]; /* The static distance tree. (Actually a trivial tree since all codes use * 5 bits.) */ -static ct_data bl_tree[2 * BL_CODES + 1]; + ct_data bl_tree[2 * BL_CODES + 1]; /* Huffman tree for the bit lengths */ -typedef struct tree_desc { - ct_data *dyn_tree; /* the dynamic tree */ - ct_data *static_tree; /* corresponding static tree or NULL */ - const extra_bits_t *extra_bits; /* extra bits for each code or NULL */ - int extra_base; /* base index for extra_bits */ - int elems; /* max number of elements in the tree */ - int max_length; /* max bit length for the codes */ - int max_code; /* largest code with non zero frequency */ -} tree_desc; - -static tree_desc l_desc = { - dyn_ltree, static_ltree, extra_lbits, - LITERALS + 1, L_CODES, MAX_BITS, 0 -}; - -static tree_desc d_desc = { - dyn_dtree, static_dtree, extra_dbits, 0, D_CODES, MAX_BITS, 0 -}; - -static tree_desc bl_desc = { - bl_tree, NULL, extra_blbits, 0, BL_CODES, MAX_BL_BITS, 0 -}; - + tree_desc l_desc; + tree_desc d_desc; + tree_desc bl_desc; -static ush bl_count[MAX_BITS + 1]; - -/* number of codes at each bit length for an optimal tree */ - -static const uch bl_order[BL_CODES] = { - 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 -}; + ush bl_count[MAX_BITS + 1]; /* The lengths of the bit length codes are sent in order of decreasing * probability, to avoid transmitting the lengths for unused bit length codes. */ -static int heap[2 * L_CODES + 1]; /* heap used to build the Huffman trees */ -static int heap_len; /* number of elements in the heap */ -static int heap_max; /* element of largest frequency */ - -/* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used. - * The same heap array is used to build all trees. - */ - -static uch depth[2 * L_CODES + 1]; + uch depth[2 * L_CODES + 1]; /* Depth of each subtree used as tie breaker for trees of equal frequency */ -static uch length_code[MAX_MATCH - MIN_MATCH + 1]; + uch length_code[MAX_MATCH - MIN_MATCH + 1]; /* length code for each normalized match length (0 == MIN_MATCH) */ -static uch dist_code[512]; + uch dist_code[512]; /* distance codes. The first 256 values correspond to the distances * 3 .. 258, the last 256 values correspond to the top 8 bits of * the 15 bit distances. */ -static int base_length[LENGTH_CODES]; + int base_length[LENGTH_CODES]; /* First normalized length for each code (0 = MIN_MATCH) */ -static int base_dist[D_CODES]; + int base_dist[D_CODES]; /* First normalized distance for each code (0 = distance of 1) */ -#define l_buf inbuf -/* DECLARE(uch, l_buf, LIT_BUFSIZE); buffer for literals or lengths */ - -/* DECLARE(ush, d_buf, DIST_BUFSIZE); buffer for distances */ - -static uch flag_buf[(LIT_BUFSIZE / 8)]; + uch flag_buf[LIT_BUFSIZE / 8]; /* flag_buf is a bit array distinguishing literals from lengths in * l_buf, thus indicating the presence or absence of a distance. */ -static unsigned last_lit; /* running index in l_buf */ -static unsigned last_dist; /* running index in d_buf */ -static unsigned last_flags; /* running index in flag_buf */ -static uch flags; /* current flags not yet saved in flag_buf */ -static uch flag_bit; /* current bit used in flags */ + unsigned last_lit; /* running index in l_buf */ + unsigned last_dist; /* running index in d_buf */ + unsigned last_flags; /* running index in flag_buf */ + uch flags; /* current flags not yet saved in flag_buf */ + uch flag_bit; /* current bit used in flags */ /* bits are filled in flags starting at bit 0 (least significant). * Note: these flags are overkill in the current code since we don't * take advantage of DIST_BUFSIZE == LIT_BUFSIZE. */ -static ulg opt_len; /* bit length of current block with optimal trees */ -static ulg static_len; /* bit length of current block with static trees */ + ulg opt_len; /* bit length of current block with optimal trees */ + ulg static_len; /* bit length of current block with static trees */ -static ulg compressed_len; /* total bit length of compressed file */ + ulg compressed_len; /* total bit length of compressed file */ +}; +#define G2ptr ((struct globals2*)(ptr_to_globals)) +#define G2 (*G2ptr) -static ush *file_type; /* pointer to UNKNOWN, BINARY or ASCII */ -static int *file_method; /* pointer to DEFLATE or STORE */ /* =========================================================================== - * Local (static) routines in this file. */ - -static void init_block(void); -static void pqdownheap(ct_data * tree, int k); -static void gen_bitlen(tree_desc * desc); static void gen_codes(ct_data * tree, int max_code); static void build_tree(tree_desc * desc); static void scan_tree(ct_data * tree, int max_code); @@ -1410,153 +967,50 @@ static void send_tree(ct_data * tree, int max_code); static int build_bl_tree(void); static void send_all_trees(int lcodes, int dcodes, int blcodes); static void compress_block(ct_data * ltree, ct_data * dtree); -static void set_file_type(void); #ifndef DEBUG -# define send_code(c, tree) send_bits(tree[c].Code, tree[c].Len) - /* Send a code of the given tree. c and tree must not have side effects */ - -#else /* DEBUG */ -# define send_code(c, tree) \ - { if (verbose>1) bb_error_msg("\ncd %3d ",(c)); \ - send_bits(tree[c].Code, tree[c].Len); } +/* Send a code of the given tree. c and tree must not have side effects */ +# define SEND_CODE(c, tree) send_bits(tree[c].Code, tree[c].Len) +#else +# define SEND_CODE(c, tree) \ +{ \ + if (verbose > 1) bb_error_msg("\ncd %3d ",(c)); \ + send_bits(tree[c].Code, tree[c].Len); \ +} #endif -#define d_code(dist) \ - ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) +#define D_CODE(dist) \ + ((dist) < 256 ? G2.dist_code[dist] : G2.dist_code[256 + ((dist)>>7)]) /* Mapping from a distance to a distance code. dist is the distance - 1 and * must not have side effects. dist_code[256] and dist_code[257] are never * used. + * The arguments must not have side effects. */ -/* the arguments must not have side effects */ - -/* =========================================================================== - * Allocate the match buffer, initialize the various tables and save the - * location of the internal file attribute (ascii/binary) and method - * (DEFLATE/STORE). - */ -static void ct_init(ush * attr, int *methodp) -{ - int n; /* iterates over tree elements */ - int bits; /* bit counter */ - int length; /* length value */ - int code; /* code value */ - int dist; /* distance index */ - - file_type = attr; - file_method = methodp; - compressed_len = 0L; - - if (static_dtree[0].Len != 0) - return; /* ct_init already called */ - - /* Initialize the mapping length (0..255) -> length code (0..28) */ - length = 0; - for (code = 0; code < LENGTH_CODES - 1; code++) { - base_length[code] = length; - for (n = 0; n < (1 << extra_lbits[code]); n++) { - length_code[length++] = (uch) code; - } - } - Assert(length == 256, "ct_init: length != 256"); - /* Note that the length 255 (match length 258) can be represented - * in two different ways: code 284 + 5 bits or code 285, so we - * overwrite length_code[255] to use the best encoding: - */ - length_code[length - 1] = (uch) code; - - /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ - dist = 0; - for (code = 0; code < 16; code++) { - base_dist[code] = dist; - for (n = 0; n < (1 << extra_dbits[code]); n++) { - dist_code[dist++] = (uch) code; - } - } - Assert(dist == 256, "ct_init: dist != 256"); - dist >>= 7; /* from now on, all distances are divided by 128 */ - for (; code < D_CODES; code++) { - base_dist[code] = dist << 7; - for (n = 0; n < (1 << (extra_dbits[code] - 7)); n++) { - dist_code[256 + dist++] = (uch) code; - } - } - Assert(dist == 256, "ct_init: 256+dist != 512"); - - /* Construct the codes of the static literal tree */ - for (bits = 0; bits <= MAX_BITS; bits++) - bl_count[bits] = 0; - n = 0; - while (n <= 143) - static_ltree[n++].Len = 8, bl_count[8]++; - while (n <= 255) - static_ltree[n++].Len = 9, bl_count[9]++; - while (n <= 279) - static_ltree[n++].Len = 7, bl_count[7]++; - while (n <= 287) - static_ltree[n++].Len = 8, bl_count[8]++; - /* Codes 286 and 287 do not exist, but we must include them in the - * tree construction to get a canonical Huffman tree (longest code - * all ones) - */ - gen_codes((ct_data *) static_ltree, L_CODES + 1); - - /* The static distance tree is trivial: */ - for (n = 0; n < D_CODES; n++) { - static_dtree[n].Len = 5; - static_dtree[n].Code = bi_reverse(n, 5); - } - - /* Initialize the first block of the first file: */ - init_block(); -} /* =========================================================================== * Initialize a new block. */ static void init_block(void) { - int n; /* iterates over tree elements */ + int n; /* iterates over tree elements */ /* Initialize the trees. */ for (n = 0; n < L_CODES; n++) - dyn_ltree[n].Freq = 0; + G2.dyn_ltree[n].Freq = 0; for (n = 0; n < D_CODES; n++) - dyn_dtree[n].Freq = 0; + G2.dyn_dtree[n].Freq = 0; for (n = 0; n < BL_CODES; n++) - bl_tree[n].Freq = 0; - - dyn_ltree[END_BLOCK].Freq = 1; - opt_len = static_len = 0L; - last_lit = last_dist = last_flags = 0; - flags = 0; - flag_bit = 1; -} + G2.bl_tree[n].Freq = 0; -#define SMALLEST 1 -/* Index within the heap array of least frequent node in the Huffman tree */ - - -/* =========================================================================== - * Remove the smallest element from the heap and recreate the heap with - * one less element. Updates heap and heap_len. - */ -#define pqremove(tree, top) \ -{\ - top = heap[SMALLEST]; \ - heap[SMALLEST] = heap[heap_len--]; \ - pqdownheap(tree, SMALLEST); \ + G2.dyn_ltree[END_BLOCK].Freq = 1; + G2.opt_len = G2.static_len = 0; + G2.last_lit = G2.last_dist = G2.last_flags = 0; + G2.flags = 0; + G2.flag_bit = 1; } -/* =========================================================================== - * Compares to subtrees, using the tree depth as tie breaker when - * the subtrees have equal frequency. This minimizes the worst case length. - */ -#define smaller(tree, n, m) \ - (tree[n].Freq < tree[m].Freq || \ - (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) /* =========================================================================== * Restore the heap property by moving down the tree starting at node k, @@ -1564,30 +1018,38 @@ static void init_block(void) * when the heap property is re-established (each father smaller than its * two sons). */ + +/* Compares to subtrees, using the tree depth as tie breaker when + * the subtrees have equal frequency. This minimizes the worst case length. */ +#define SMALLER(tree, n, m) \ + (tree[n].Freq < tree[m].Freq \ + || (tree[n].Freq == tree[m].Freq && G2.depth[n] <= G2.depth[m])) + static void pqdownheap(ct_data * tree, int k) { - int v = heap[k]; + int v = G2.heap[k]; int j = k << 1; /* left son of k */ - while (j <= heap_len) { + while (j <= G2.heap_len) { /* Set j to the smallest of the two sons: */ - if (j < heap_len && smaller(tree, heap[j + 1], heap[j])) + if (j < G2.heap_len && SMALLER(tree, G2.heap[j + 1], G2.heap[j])) j++; /* Exit if v is smaller than both sons */ - if (smaller(tree, v, heap[j])) + if (SMALLER(tree, v, G2.heap[j])) break; /* Exchange v with the smallest son */ - heap[k] = heap[j]; + G2.heap[k] = G2.heap[j]; k = j; /* And continue down the tree, setting j to the left son of k */ j <<= 1; } - heap[k] = v; + G2.heap[k] = v; } + /* =========================================================================== * Compute the optimal bit lengths for a tree and update the total bit length * for the current block. @@ -1601,7 +1063,7 @@ static void pqdownheap(ct_data * tree, int k) static void gen_bitlen(tree_desc * desc) { ct_data *tree = desc->dyn_tree; - const extra_bits_t *extra = desc->extra_bits; + const uint8_t *extra = desc->extra_bits; int base = desc->extra_base; int max_code = desc->max_code; int max_length = desc->max_length; @@ -1614,33 +1076,35 @@ static void gen_bitlen(tree_desc * desc) int overflow = 0; /* number of elements with bit length too large */ for (bits = 0; bits <= MAX_BITS; bits++) - bl_count[bits] = 0; + G2.bl_count[bits] = 0; /* In a first pass, compute the optimal bit lengths (which may * overflow in the case of the bit length tree). */ - tree[heap[heap_max]].Len = 0; /* root of the heap */ + tree[G2.heap[G2.heap_max]].Len = 0; /* root of the heap */ - for (h = heap_max + 1; h < HEAP_SIZE; h++) { - n = heap[h]; + for (h = G2.heap_max + 1; h < HEAP_SIZE; h++) { + n = G2.heap[h]; bits = tree[tree[n].Dad].Len + 1; - if (bits > max_length) - bits = max_length, overflow++; + if (bits > max_length) { + bits = max_length; + overflow++; + } tree[n].Len = (ush) bits; /* We overwrite tree[n].Dad which is no longer needed */ if (n > max_code) continue; /* not a leaf node */ - bl_count[bits]++; + G2.bl_count[bits]++; xbits = 0; if (n >= base) xbits = extra[n - base]; f = tree[n].Freq; - opt_len += (ulg) f *(bits + xbits); + G2.opt_len += (ulg) f *(bits + xbits); if (stree) - static_len += (ulg) f *(stree[n].Len + xbits); + G2.static_len += (ulg) f * (stree[n].Len + xbits); } if (overflow == 0) return; @@ -1651,11 +1115,11 @@ static void gen_bitlen(tree_desc * desc) /* Find the first bit length which could increase: */ do { bits = max_length - 1; - while (bl_count[bits] == 0) + while (G2.bl_count[bits] == 0) bits--; - bl_count[bits]--; /* move one leaf down the tree */ - bl_count[bits + 1] += 2; /* move one overflow item as its brother */ - bl_count[max_length]--; + G2.bl_count[bits]--; /* move one leaf down the tree */ + G2.bl_count[bits + 1] += 2; /* move one overflow item as its brother */ + G2.bl_count[max_length]--; /* The brother of the overflow item also moves one step up, * but this does not affect bl_count[max_length] */ @@ -1668,23 +1132,22 @@ static void gen_bitlen(tree_desc * desc) * from 'ar' written by Haruhiko Okumura.) */ for (bits = max_length; bits != 0; bits--) { - n = bl_count[bits]; + n = G2.bl_count[bits]; while (n != 0) { - m = heap[--h]; + m = G2.heap[--h]; if (m > max_code) continue; if (tree[m].Len != (unsigned) bits) { - Trace((stderr, "code %d bits %d->%d\n", m, tree[m].Len, - bits)); - opt_len += - ((long) bits - (long) tree[m].Len) * (long) tree[m].Freq; - tree[m].Len = (ush) bits; + Trace((stderr, "code %d bits %d->%d\n", m, tree[m].Len, bits)); + G2.opt_len += ((int32_t) bits - tree[m].Len) * tree[m].Freq; + tree[m].Len = bits; } n--; } } } + /* =========================================================================== * Generate the codes for a given tree and bit counts (which need not be * optimal). @@ -1704,12 +1167,12 @@ static void gen_codes(ct_data * tree, int max_code) * without bit reversal. */ for (bits = 1; bits <= MAX_BITS; bits++) { - next_code[bits] = code = (code + bl_count[bits - 1]) << 1; + next_code[bits] = code = (code + G2.bl_count[bits - 1]) << 1; } /* Check that the bit counts in bl_count are consistent. The last code * must be all ones. */ - Assert(code + bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1, + Assert(code + G2.bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1, "inconsistent bit counts"); Tracev((stderr, "\ngen_codes: max_code %d ", max_code)); @@ -1721,13 +1184,14 @@ static void gen_codes(ct_data * tree, int max_code) /* Now reverse the bits */ tree[n].Code = bi_reverse(next_code[len]++, len); - Tracec(tree != static_ltree, + Tracec(tree != G2.static_ltree, (stderr, "\nn %3d %c l %2d c %4x (%x) ", n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len] - 1)); } } + /* =========================================================================== * Construct one Huffman tree and assigns the code bit strings and lengths. * Update the total bit length for the current block. @@ -1736,6 +1200,20 @@ static void gen_codes(ct_data * tree, int max_code) * and corresponding code. The length opt_len is updated; static_len is * also updated if stree is not null. The field max_code is set. */ + +/* Remove the smallest element from the heap and recreate the heap with + * one less element. Updates heap and heap_len. */ + +#define SMALLEST 1 +/* Index within the heap array of least frequent node in the Huffman tree */ + +#define PQREMOVE(tree, top) \ +do { \ + top = G2.heap[SMALLEST]; \ + G2.heap[SMALLEST] = G2.heap[G2.heap_len--]; \ + pqdownheap(tree, SMALLEST); \ +} while (0) + static void build_tree(tree_desc * desc) { ct_data *tree = desc->dyn_tree; @@ -1749,12 +1227,13 @@ static void build_tree(tree_desc * desc) * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. * heap[0] is not used. */ - heap_len = 0, heap_max = HEAP_SIZE; + G2.heap_len = 0; + G2.heap_max = HEAP_SIZE; for (n = 0; n < elems; n++) { if (tree[n].Freq != 0) { - heap[++heap_len] = max_code = n; - depth[n] = 0; + G2.heap[++G2.heap_len] = max_code = n; + G2.depth[n] = 0; } else { tree[n].Len = 0; } @@ -1765,14 +1244,14 @@ static void build_tree(tree_desc * desc) * possible code. So to avoid special checks later on we force at least * two codes of non zero frequency. */ - while (heap_len < 2) { - int new = heap[++heap_len] = (max_code < 2 ? ++max_code : 0); + while (G2.heap_len < 2) { + int new = G2.heap[++G2.heap_len] = (max_code < 2 ? ++max_code : 0); tree[new].Freq = 1; - depth[new] = 0; - opt_len--; + G2.depth[new] = 0; + G2.opt_len--; if (stree) - static_len -= stree[new].Len; + G2.static_len -= stree[new].Len; /* new is 0 or 1 so it does not have extra bits */ } desc->max_code = max_code; @@ -1780,36 +1259,36 @@ static void build_tree(tree_desc * desc) /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, * establish sub-heaps of increasing lengths: */ - for (n = heap_len / 2; n >= 1; n--) + for (n = G2.heap_len / 2; n >= 1; n--) pqdownheap(tree, n); /* Construct the Huffman tree by repeatedly combining the least two * frequent nodes. */ do { - pqremove(tree, n); /* n = node of least frequency */ - m = heap[SMALLEST]; /* m = node of next least frequency */ + PQREMOVE(tree, n); /* n = node of least frequency */ + m = G2.heap[SMALLEST]; /* m = node of next least frequency */ - heap[--heap_max] = n; /* keep the nodes sorted by frequency */ - heap[--heap_max] = m; + G2.heap[--G2.heap_max] = n; /* keep the nodes sorted by frequency */ + G2.heap[--G2.heap_max] = m; /* Create a new node father of n and m */ tree[node].Freq = tree[n].Freq + tree[m].Freq; - depth[node] = (uch) (MAX(depth[n], depth[m]) + 1); + G2.depth[node] = MAX(G2.depth[n], G2.depth[m]) + 1; tree[n].Dad = tree[m].Dad = (ush) node; #ifdef DUMP_BL_TREE - if (tree == bl_tree) { + if (tree == G2.bl_tree) { bb_error_msg("\nnode %d(%d), sons %d(%d) %d(%d)", node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); } #endif /* and insert the new node in the heap */ - heap[SMALLEST] = node++; + G2.heap[SMALLEST] = node++; pqdownheap(tree, SMALLEST); - } while (heap_len >= 2); + } while (G2.heap_len >= 2); - heap[--heap_max] = heap[SMALLEST]; + G2.heap[--G2.heap_max] = G2.heap[SMALLEST]; /* At this point, the fields freq and dad are set. We can now * generate the bit lengths. @@ -1820,6 +1299,7 @@ static void build_tree(tree_desc * desc) gen_codes((ct_data *) tree, max_code); } + /* =========================================================================== * Scan a literal or distance tree to determine the frequencies of the codes * in the bit length tree. Updates opt_len to take into account the repeat @@ -1836,38 +1316,45 @@ static void scan_tree(ct_data * tree, int max_code) int max_count = 7; /* max repeat count */ int min_count = 4; /* min repeat count */ - if (nextlen == 0) - max_count = 138, min_count = 3; - tree[max_code + 1].Len = (ush) 0xffff; /* guard */ + if (nextlen == 0) { + max_count = 138; + min_count = 3; + } + tree[max_code + 1].Len = 0xffff; /* guard */ for (n = 0; n <= max_code; n++) { curlen = nextlen; nextlen = tree[n + 1].Len; - if (++count < max_count && curlen == nextlen) { + if (++count < max_count && curlen == nextlen) continue; - } else if (count < min_count) { - bl_tree[curlen].Freq += count; + + if (count < min_count) { + G2.bl_tree[curlen].Freq += count; } else if (curlen != 0) { if (curlen != prevlen) - bl_tree[curlen].Freq++; - bl_tree[REP_3_6].Freq++; + G2.bl_tree[curlen].Freq++; + G2.bl_tree[REP_3_6].Freq++; } else if (count <= 10) { - bl_tree[REPZ_3_10].Freq++; + G2.bl_tree[REPZ_3_10].Freq++; } else { - bl_tree[REPZ_11_138].Freq++; + G2.bl_tree[REPZ_11_138].Freq++; } count = 0; prevlen = curlen; + + max_count = 7; + min_count = 4; if (nextlen == 0) { - max_count = 138, min_count = 3; + max_count = 138; + min_count = 3; } else if (curlen == nextlen) { - max_count = 6, min_count = 3; - } else { - max_count = 7, min_count = 4; + max_count = 6; + min_count = 3; } } } + /* =========================================================================== * Send a literal or distance tree in compressed form, using the codes in * bl_tree. @@ -1893,38 +1380,39 @@ static void send_tree(ct_data * tree, int max_code) continue; } else if (count < min_count) { do { - send_code(curlen, bl_tree); - } while (--count != 0); - + SEND_CODE(curlen, G2.bl_tree); + } while (--count); } else if (curlen != 0) { if (curlen != prevlen) { - send_code(curlen, bl_tree); + SEND_CODE(curlen, G2.bl_tree); count--; } Assert(count >= 3 && count <= 6, " 3_6?"); - send_code(REP_3_6, bl_tree); + SEND_CODE(REP_3_6, G2.bl_tree); send_bits(count - 3, 2); - } else if (count <= 10) { - send_code(REPZ_3_10, bl_tree); + SEND_CODE(REPZ_3_10, G2.bl_tree); send_bits(count - 3, 3); - } else { - send_code(REPZ_11_138, bl_tree); + SEND_CODE(REPZ_11_138, G2.bl_tree); send_bits(count - 11, 7); } count = 0; prevlen = curlen; if (nextlen == 0) { - max_count = 138, min_count = 3; + max_count = 138; + min_count = 3; } else if (curlen == nextlen) { - max_count = 6, min_count = 3; + max_count = 6; + min_count = 3; } else { - max_count = 7, min_count = 4; + max_count = 7; + min_count = 4; } } } + /* =========================================================================== * Construct the Huffman tree for the bit lengths and return the index in * bl_order of the last bit length code to send. @@ -1934,11 +1422,11 @@ static int build_bl_tree(void) int max_blindex; /* index of last bit length code of non zero freq */ /* Determine the bit length frequencies for literal and distance trees */ - scan_tree((ct_data *) dyn_ltree, l_desc.max_code); - scan_tree((ct_data *) dyn_dtree, d_desc.max_code); + scan_tree(G2.dyn_ltree, G2.l_desc.max_code); + scan_tree(G2.dyn_dtree, G2.d_desc.max_code); /* Build the bit length tree: */ - build_tree((tree_desc *) (&bl_desc)); + build_tree(&G2.bl_desc); /* opt_len now includes the length of the tree representations, except * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. */ @@ -1948,16 +1436,17 @@ static int build_bl_tree(void) * 3 but the actual value used is 4.) */ for (max_blindex = BL_CODES - 1; max_blindex >= 3; max_blindex--) { - if (bl_tree[bl_order[max_blindex]].Len != 0) + if (G2.bl_tree[bl_order[max_blindex]].Len != 0) break; } /* Update opt_len to include the bit length tree and counts */ - opt_len += 3 * (max_blindex + 1) + 5 + 5 + 4; - Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", opt_len, static_len)); + G2.opt_len += 3 * (max_blindex + 1) + 5 + 5 + 4; + Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", G2.opt_len, G2.static_len)); return max_blindex; } + /* =========================================================================== * Send the header for a block using dynamic Huffman trees: the counts, the * lengths of the bit length codes, the literal tree and the distance tree. @@ -1976,17 +1465,124 @@ static void send_all_trees(int lcodes, int dcodes, int blcodes) send_bits(blcodes - 4, 4); /* not -3 as stated in appnote.txt */ for (rank = 0; rank < blcodes; rank++) { Tracev((stderr, "\nbl code %2d ", bl_order[rank])); - send_bits(bl_tree[bl_order[rank]].Len, 3); + send_bits(G2.bl_tree[bl_order[rank]].Len, 3); + } + Tracev((stderr, "\nbl tree: sent %ld", G1.bits_sent)); + + send_tree((ct_data *) G2.dyn_ltree, lcodes - 1); /* send the literal tree */ + Tracev((stderr, "\nlit tree: sent %ld", G1.bits_sent)); + + send_tree((ct_data *) G2.dyn_dtree, dcodes - 1); /* send the distance tree */ + Tracev((stderr, "\ndist tree: sent %ld", G1.bits_sent)); +} + + +/* =========================================================================== + * Save the match info and tally the frequency counts. Return true if + * the current block must be flushed. + */ +static int ct_tally(int dist, int lc) +{ + G1.l_buf[G2.last_lit++] = lc; + if (dist == 0) { + /* lc is the unmatched char */ + G2.dyn_ltree[lc].Freq++; + } else { + /* Here, lc is the match length - MIN_MATCH */ + dist--; /* dist = match distance - 1 */ + Assert((ush) dist < (ush) MAX_DIST + && (ush) lc <= (ush) (MAX_MATCH - MIN_MATCH) + && (ush) D_CODE(dist) < (ush) D_CODES, "ct_tally: bad match" + ); + + G2.dyn_ltree[G2.length_code[lc] + LITERALS + 1].Freq++; + G2.dyn_dtree[D_CODE(dist)].Freq++; + + G1.d_buf[G2.last_dist++] = dist; + G2.flags |= G2.flag_bit; + } + G2.flag_bit <<= 1; + + /* Output the flags if they fill a byte: */ + if ((G2.last_lit & 7) == 0) { + G2.flag_buf[G2.last_flags++] = G2.flags; + G2.flags = 0; + G2.flag_bit = 1; + } + /* Try to guess if it is profitable to stop the current block here */ + if ((G2.last_lit & 0xfff) == 0) { + /* Compute an upper bound for the compressed length */ + ulg out_length = G2.last_lit * 8L; + ulg in_length = (ulg) G1.strstart - G1.block_start; + int dcode; + + for (dcode = 0; dcode < D_CODES; dcode++) { + out_length += G2.dyn_dtree[dcode].Freq * (5L + extra_dbits[dcode]); + } + out_length >>= 3; + Trace((stderr, + "\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ", + G2.last_lit, G2.last_dist, in_length, out_length, + 100L - out_length * 100L / in_length)); + if (G2.last_dist < G2.last_lit / 2 && out_length < in_length / 2) + return 1; } - Tracev((stderr, "\nbl tree: sent %ld", bits_sent)); + return (G2.last_lit == LIT_BUFSIZE - 1 || G2.last_dist == DIST_BUFSIZE); + /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K + * on 16 bit machines and because stored blocks are restricted to + * 64K-1 bytes. + */ +} - send_tree((ct_data *) dyn_ltree, lcodes - 1); /* send the literal tree */ - Tracev((stderr, "\nlit tree: sent %ld", bits_sent)); +/* =========================================================================== + * Send the block data compressed using the given Huffman trees + */ +static void compress_block(ct_data * ltree, ct_data * dtree) +{ + unsigned dist; /* distance of matched string */ + int lc; /* match length or unmatched char (if dist == 0) */ + unsigned lx = 0; /* running index in l_buf */ + unsigned dx = 0; /* running index in d_buf */ + unsigned fx = 0; /* running index in flag_buf */ + uch flag = 0; /* current flags */ + unsigned code; /* the code to send */ + int extra; /* number of extra bits to send */ + + if (G2.last_lit != 0) do { + if ((lx & 7) == 0) + flag = G2.flag_buf[fx++]; + lc = G1.l_buf[lx++]; + if ((flag & 1) == 0) { + SEND_CODE(lc, ltree); /* send a literal byte */ + Tracecv(isgraph(lc), (stderr, " '%c' ", lc)); + } else { + /* Here, lc is the match length - MIN_MATCH */ + code = G2.length_code[lc]; + SEND_CODE(code + LITERALS + 1, ltree); /* send the length code */ + extra = extra_lbits[code]; + if (extra != 0) { + lc -= G2.base_length[code]; + send_bits(lc, extra); /* send the extra length bits */ + } + dist = G1.d_buf[dx++]; + /* Here, dist is the match distance - 1 */ + code = D_CODE(dist); + Assert(code < D_CODES, "bad d_code"); + + SEND_CODE(code, dtree); /* send the distance code */ + extra = extra_dbits[code]; + if (extra != 0) { + dist -= G2.base_dist[code]; + send_bits(dist, extra); /* send the extra distance bits */ + } + } /* literal or match pair ? */ + flag >>= 1; + } while (lx < G2.last_lit); - send_tree((ct_data *) dyn_dtree, dcodes - 1); /* send the distance tree */ - Tracev((stderr, "\ndist tree: sent %ld", bits_sent)); + SEND_CODE(END_BLOCK, ltree); } + /* =========================================================================== * Determine the best encoding for the current block: dynamic trees, static * trees or store, and output the encoded block to the zip file. This function @@ -1994,21 +1590,17 @@ static void send_all_trees(int lcodes, int dcodes, int blcodes) */ static ulg flush_block(char *buf, ulg stored_len, int eof) { - ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ - int max_blindex; /* index of last bit length code of non zero freq */ - - flag_buf[last_flags] = flags; /* Save the flags for the last 8 items */ + ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ + int max_blindex; /* index of last bit length code of non zero freq */ - /* Check if the file is ascii or binary */ - if (*file_type == (ush) UNKNOWN) - set_file_type(); + G2.flag_buf[G2.last_flags] = G2.flags; /* Save the flags for the last 8 items */ /* Construct the literal and distance trees */ - build_tree((tree_desc *) (&l_desc)); - Tracev((stderr, "\nlit data: dyn %ld, stat %ld", opt_len, static_len)); + build_tree(&G2.l_desc); + Tracev((stderr, "\nlit data: dyn %ld, stat %ld", G2.opt_len, G2.static_len)); - build_tree((tree_desc *) (&d_desc)); - Tracev((stderr, "\ndist data: dyn %ld, stat %ld", opt_len, static_len)); + build_tree(&G2.d_desc); + Tracev((stderr, "\ndist data: dyn %ld, stat %ld", G2.opt_len, G2.static_len)); /* At this point, opt_len and static_len are the total bit lengths of * the compressed block data, excluding the tree representations. */ @@ -2019,13 +1611,13 @@ static ulg flush_block(char *buf, ulg stored_len, int eof) max_blindex = build_bl_tree(); /* Determine the best encoding. Compute first the block length in bytes */ - opt_lenb = (opt_len + 3 + 7) >> 3; - static_lenb = (static_len + 3 + 7) >> 3; + opt_lenb = (G2.opt_len + 3 + 7) >> 3; + static_lenb = (G2.static_len + 3 + 7) >> 3; Trace((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ", - opt_lenb, opt_len, static_lenb, static_len, stored_len, - last_lit, last_dist)); + opt_lenb, G2.opt_len, static_lenb, G2.static_len, stored_len, + G2.last_lit, G2.last_dist)); if (static_lenb <= opt_lenb) opt_lenb = static_lenb; @@ -2034,16 +1626,15 @@ static ulg flush_block(char *buf, ulg stored_len, int eof) * and if the zip file can be seeked (to rewrite the local header), * the whole file is transformed into a stored file: */ - if (stored_len <= opt_lenb && eof && compressed_len == 0L && seekable()) { + if (stored_len <= opt_lenb && eof && G2.compressed_len == 0L && seekable()) { /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ - if (buf == (char *) 0) + if (buf == NULL) bb_error_msg("block vanished"); copy_block(buf, (unsigned) stored_len, 0); /* without header */ - compressed_len = stored_len << 3; - *file_method = STORED; + G2.compressed_len = stored_len << 3; - } else if (stored_len + 4 <= opt_lenb && buf != (char *) 0) { + } else if (stored_len + 4 <= opt_lenb && buf != NULL) { /* 4: two words for the lengths */ /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. * Otherwise we can't have processed more than WSIZE input bytes since @@ -2052,205 +1643,460 @@ static ulg flush_block(char *buf, ulg stored_len, int eof) * transform a block into a stored block. */ send_bits((STORED_BLOCK << 1) + eof, 3); /* send block type */ - compressed_len = (compressed_len + 3 + 7) & ~7L; - compressed_len += (stored_len + 4) << 3; + G2.compressed_len = (G2.compressed_len + 3 + 7) & ~7L; + G2.compressed_len += (stored_len + 4) << 3; copy_block(buf, (unsigned) stored_len, 1); /* with header */ } else if (static_lenb == opt_lenb) { send_bits((STATIC_TREES << 1) + eof, 3); - compress_block((ct_data *) static_ltree, (ct_data *) static_dtree); - compressed_len += 3 + static_len; + compress_block((ct_data *) G2.static_ltree, (ct_data *) G2.static_dtree); + G2.compressed_len += 3 + G2.static_len; } else { send_bits((DYN_TREES << 1) + eof, 3); - send_all_trees(l_desc.max_code + 1, d_desc.max_code + 1, + send_all_trees(G2.l_desc.max_code + 1, G2.d_desc.max_code + 1, max_blindex + 1); - compress_block((ct_data *) dyn_ltree, (ct_data *) dyn_dtree); - compressed_len += 3 + opt_len; + compress_block((ct_data *) G2.dyn_ltree, (ct_data *) G2.dyn_dtree); + G2.compressed_len += 3 + G2.opt_len; } - Assert(compressed_len == bits_sent, "bad compressed size"); + Assert(G2.compressed_len == G1.bits_sent, "bad compressed size"); init_block(); if (eof) { bi_windup(); - compressed_len += 7; /* align on byte boundary */ + G2.compressed_len += 7; /* align on byte boundary */ } - Tracev((stderr, "\ncomprlen %lu(%lu) ", compressed_len >> 3, - compressed_len - 7 * eof)); + Tracev((stderr, "\ncomprlen %lu(%lu) ", G2.compressed_len >> 3, + G2.compressed_len - 7 * eof)); - return compressed_len >> 3; + return G2.compressed_len >> 3; } + /* =========================================================================== - * Save the match info and tally the frequency counts. Return true if - * the current block must be flushed. + * Update a hash value with the given input byte + * IN assertion: all calls to to UPDATE_HASH are made with consecutive + * input characters, so that a running hash key can be computed from the + * previous key instead of complete recalculation each time. */ -static int ct_tally(int dist, int lc) +#define UPDATE_HASH(h, c) (h = (((h)<= 0L \ + ? (char*)&G1.window[(unsigned)G1.block_start] \ + : (char*)NULL, \ + (ulg)G1.strstart - G1.block_start, \ + (eof) \ + ) + +/* Insert string s in the dictionary and set match_head to the previous head + * of the hash chain (the most recent string with same hash key). Return + * the previous length of the hash chain. + * IN assertion: all calls to to INSERT_STRING are made with consecutive + * input characters and the first MIN_MATCH bytes of s are valid + * (except for the last MIN_MATCH-1 bytes of the input file). */ +#define INSERT_STRING(s, match_head) \ +do { \ + UPDATE_HASH(G1.ins_h, G1.window[(s) + MIN_MATCH-1]); \ + G1.prev[(s) & WMASK] = match_head = head[G1.ins_h]; \ + head[G1.ins_h] = (s); \ +} while (0) + +static ulg deflate(void) { - l_buf[last_lit++] = (uch) lc; - if (dist == 0) { - /* lc is the unmatched char */ - dyn_ltree[lc].Freq++; - } else { - /* Here, lc is the match length - MIN_MATCH */ - dist--; /* dist = match distance - 1 */ - Assert((ush) dist < (ush) MAX_DIST && - (ush) lc <= (ush) (MAX_MATCH - MIN_MATCH) && - (ush) d_code(dist) < (ush) D_CODES, "ct_tally: bad match"); + IPos hash_head; /* head of hash chain */ + IPos prev_match; /* previous match */ + int flush; /* set if current block must be flushed */ + int match_available = 0; /* set if previous match exists */ + unsigned match_length = MIN_MATCH - 1; /* length of best match */ - dyn_ltree[length_code[lc] + LITERALS + 1].Freq++; - dyn_dtree[d_code(dist)].Freq++; + /* Process the input block. */ + while (G1.lookahead != 0) { + /* Insert the string window[strstart .. strstart+2] in the + * dictionary, and set hash_head to the head of the hash chain: + */ + INSERT_STRING(G1.strstart, hash_head); - d_buf[last_dist++] = (ush) dist; - flags |= flag_bit; - } - flag_bit <<= 1; + /* Find the longest match, discarding those <= prev_length. + */ + G1.prev_length = match_length; + prev_match = G1.match_start; + match_length = MIN_MATCH - 1; - /* Output the flags if they fill a byte: */ - if ((last_lit & 7) == 0) { - flag_buf[last_flags++] = flags; - flags = 0, flag_bit = 1; - } - /* Try to guess if it is profitable to stop the current block here */ - if ((last_lit & 0xfff) == 0) { - /* Compute an upper bound for the compressed length */ - ulg out_length = (ulg) last_lit * 8L; - ulg in_length = (ulg) strstart - block_start; - int dcode; + if (hash_head != 0 && G1.prev_length < max_lazy_match + && G1.strstart - hash_head <= MAX_DIST + ) { + /* To simplify the code, we prevent matches with the string + * of window index 0 (in particular we have to avoid a match + * of the string with itself at the start of the input file). + */ + match_length = longest_match(hash_head); + /* longest_match() sets match_start */ + if (match_length > G1.lookahead) + match_length = G1.lookahead; - for (dcode = 0; dcode < D_CODES; dcode++) { - out_length += - (ulg) dyn_dtree[dcode].Freq * (5L + extra_dbits[dcode]); + /* Ignore a length 3 match if it is too distant: */ + if (match_length == MIN_MATCH && G1.strstart - G1.match_start > TOO_FAR) { + /* If prev_match is also MIN_MATCH, G1.match_start is garbage + * but we will ignore the current match anyway. + */ + match_length--; + } } - out_length >>= 3; - Trace((stderr, - "\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ", - last_lit, last_dist, in_length, out_length, - 100L - out_length * 100L / in_length)); - if (last_dist < last_lit / 2 && out_length < in_length / 2) - return 1; + /* If there was a match at the previous step and the current + * match is not better, output the previous match: + */ + if (G1.prev_length >= MIN_MATCH && match_length <= G1.prev_length) { + check_match(G1.strstart - 1, prev_match, G1.prev_length); + flush = ct_tally(G1.strstart - 1 - prev_match, G1.prev_length - MIN_MATCH); + + /* Insert in hash table all strings up to the end of the match. + * strstart-1 and strstart are already inserted. + */ + G1.lookahead -= G1.prev_length - 1; + G1.prev_length -= 2; + do { + G1.strstart++; + INSERT_STRING(G1.strstart, hash_head); + /* strstart never exceeds WSIZE-MAX_MATCH, so there are + * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH + * these bytes are garbage, but it does not matter since the + * next lookahead bytes will always be emitted as literals. + */ + } while (--G1.prev_length != 0); + match_available = 0; + match_length = MIN_MATCH - 1; + G1.strstart++; + if (flush) { + FLUSH_BLOCK(0); + G1.block_start = G1.strstart; + } + } else if (match_available) { + /* If there was no match at the previous position, output a + * single literal. If there was a match but the current match + * is longer, truncate the previous match to a single literal. + */ + Tracevv((stderr, "%c", G1.window[G1.strstart - 1])); + if (ct_tally(0, G1.window[G1.strstart - 1])) { + FLUSH_BLOCK(0); + G1.block_start = G1.strstart; + } + G1.strstart++; + G1.lookahead--; + } else { + /* There is no previous match to compare with, wait for + * the next step to decide. + */ + match_available = 1; + G1.strstart++; + G1.lookahead--; + } + Assert(G1.strstart <= G1.isize && lookahead <= G1.isize, "a bit too far"); + + /* Make sure that we always have enough lookahead, except + * at the end of the input file. We need MAX_MATCH bytes + * for the next match, plus MIN_MATCH bytes to insert the + * string following the next match. + */ + while (G1.lookahead < MIN_LOOKAHEAD && !G1.eofile) + fill_window(); } - return (last_lit == LIT_BUFSIZE - 1 || last_dist == DIST_BUFSIZE); - /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K - * on 16 bit machines and because stored blocks are restricted to - * 64K-1 bytes. - */ + if (match_available) + ct_tally(0, G1.window[G1.strstart - 1]); + + return FLUSH_BLOCK(1); /* eof */ } + /* =========================================================================== - * Send the block data compressed using the given Huffman trees + * Initialize the bit string routines. */ -static void compress_block(ct_data * ltree, ct_data * dtree) +static void bi_init(void) { - unsigned dist; /* distance of matched string */ - int lc; /* match length or unmatched char (if dist == 0) */ - unsigned lx = 0; /* running index in l_buf */ - unsigned dx = 0; /* running index in d_buf */ - unsigned fx = 0; /* running index in flag_buf */ - uch flag = 0; /* current flags */ - unsigned code; /* the code to send */ - int extra; /* number of extra bits to send */ - - if (last_lit != 0) - do { - if ((lx & 7) == 0) - flag = flag_buf[fx++]; - lc = l_buf[lx++]; - if ((flag & 1) == 0) { - send_code(lc, ltree); /* send a literal byte */ - Tracecv(isgraph(lc), (stderr, " '%c' ", lc)); - } else { - /* Here, lc is the match length - MIN_MATCH */ - code = length_code[lc]; - send_code(code + LITERALS + 1, ltree); /* send the length code */ - extra = extra_lbits[code]; - if (extra != 0) { - lc -= base_length[code]; - send_bits(lc, extra); /* send the extra length bits */ - } - dist = d_buf[dx++]; - /* Here, dist is the match distance - 1 */ - code = d_code(dist); - Assert(code < D_CODES, "bad d_code"); - - send_code(code, dtree); /* send the distance code */ - extra = extra_dbits[code]; - if (extra != 0) { - dist -= base_dist[code]; - send_bits(dist, extra); /* send the extra distance bits */ - } - } /* literal or match pair ? */ - flag >>= 1; - } while (lx < last_lit); - - send_code(END_BLOCK, ltree); + G1.bi_buf = 0; + G1.bi_valid = 0; +#ifdef DEBUG + G1.bits_sent = 0L; +#endif +} + + +/* =========================================================================== + * Initialize the "longest match" routines for a new file + */ +static void lm_init(ush * flagsp) +{ + unsigned j; + + /* Initialize the hash table. */ + memset(head, 0, HASH_SIZE * sizeof(*head)); + /* prev will be initialized on the fly */ + + /* speed options for the general purpose bit flag */ + *flagsp |= 2; /* FAST 4, SLOW 2 */ + /* ??? reduce max_chain_length for binary files */ + + G1.strstart = 0; + G1.block_start = 0L; + + G1.lookahead = file_read(G1.window, + sizeof(int) <= 2 ? (unsigned) WSIZE : 2 * WSIZE); + + if (G1.lookahead == 0 || G1.lookahead == (unsigned) -1) { + G1.eofile = 1; + G1.lookahead = 0; + return; + } + G1.eofile = 0; + /* Make sure that we always have enough lookahead. This is important + * if input comes from a device such as a tty. + */ + while (G1.lookahead < MIN_LOOKAHEAD && !G1.eofile) + fill_window(); + + G1.ins_h = 0; + for (j = 0; j < MIN_MATCH - 1; j++) + UPDATE_HASH(G1.ins_h, G1.window[j]); + /* If lookahead < MIN_MATCH, ins_h is garbage, but this is + * not important since only literal bytes will be emitted. + */ } + /* =========================================================================== - * Set the file type to ASCII or BINARY, using a crude approximation: - * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. - * IN assertion: the fields freq of dyn_ltree are set and the total of all - * frequencies does not exceed 64K (to fit in an int on 16 bit machines). + * Allocate the match buffer, initialize the various tables and save the + * location of the internal file attribute (ascii/binary) and method + * (DEFLATE/STORE). + * One callsite in zip() */ -static void set_file_type(void) +static void ct_init(void) { - int n = 0; - unsigned ascii_freq = 0; - unsigned bin_freq = 0; - - while (n < 7) - bin_freq += dyn_ltree[n++].Freq; - while (n < 128) - ascii_freq += dyn_ltree[n++].Freq; - while (n < LITERALS) - bin_freq += dyn_ltree[n++].Freq; - *file_type = bin_freq > (ascii_freq >> 2) ? BINARY : ASCII; - if (*file_type == BINARY && translate_eol) { - bb_error_msg("-l used on binary file"); + int n; /* iterates over tree elements */ + int length; /* length value */ + int code; /* code value */ + int dist; /* distance index */ + + G2.compressed_len = 0L; + +#ifdef NOT_NEEDED + if (G2.static_dtree[0].Len != 0) + return; /* ct_init already called */ +#endif + + /* Initialize the mapping length (0..255) -> length code (0..28) */ + length = 0; + for (code = 0; code < LENGTH_CODES - 1; code++) { + G2.base_length[code] = length; + for (n = 0; n < (1 << extra_lbits[code]); n++) { + G2.length_code[length++] = code; + } + } + Assert(length == 256, "ct_init: length != 256"); + /* Note that the length 255 (match length 258) can be represented + * in two different ways: code 284 + 5 bits or code 285, so we + * overwrite length_code[255] to use the best encoding: + */ + G2.length_code[length - 1] = code; + + /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ + dist = 0; + for (code = 0; code < 16; code++) { + G2.base_dist[code] = dist; + for (n = 0; n < (1 << extra_dbits[code]); n++) { + G2.dist_code[dist++] = code; + } + } + Assert(dist == 256, "ct_init: dist != 256"); + dist >>= 7; /* from now on, all distances are divided by 128 */ + for (; code < D_CODES; code++) { + G2.base_dist[code] = dist << 7; + for (n = 0; n < (1 << (extra_dbits[code] - 7)); n++) { + G2.dist_code[256 + dist++] = code; + } + } + Assert(dist == 256, "ct_init: 256+dist != 512"); + + /* Construct the codes of the static literal tree */ + /* already zeroed - it's in bss + for (n = 0; n <= MAX_BITS; n++) + G2.bl_count[n] = 0; */ + + n = 0; + while (n <= 143) { + G2.static_ltree[n++].Len = 8; + G2.bl_count[8]++; + } + while (n <= 255) { + G2.static_ltree[n++].Len = 9; + G2.bl_count[9]++; + } + while (n <= 279) { + G2.static_ltree[n++].Len = 7; + G2.bl_count[7]++; + } + while (n <= 287) { + G2.static_ltree[n++].Len = 8; + G2.bl_count[8]++; + } + /* Codes 286 and 287 do not exist, but we must include them in the + * tree construction to get a canonical Huffman tree (longest code + * all ones) + */ + gen_codes((ct_data *) G2.static_ltree, L_CODES + 1); + + /* The static distance tree is trivial: */ + for (n = 0; n < D_CODES; n++) { + G2.static_dtree[n].Len = 5; + G2.static_dtree[n].Code = bi_reverse(n, 5); } + + /* Initialize the first block of the first file: */ + init_block(); } + /* =========================================================================== * Deflate in to out. * IN assertions: the input and output buffers are cleared. - * The variables time_stamp and save_orig_name are initialized. */ -static int zip(int in, int out) + +static void zip(ulg time_stamp) { - uch my_flags = 0; /* general purpose bit flags */ - ush attr = 0; /* ascii/binary flag */ - ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */ + ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */ - ifd = in; - ofd = out; - outcnt = 0; + G1.outcnt = 0; /* Write the header to the gzip file. See algorithm.doc for the format */ - - method = DEFLATED; - put_header_byte(GZIP_MAGIC[0]); /* magic header */ - put_header_byte(GZIP_MAGIC[1]); - put_header_byte(DEFLATED); /* compression method */ - - put_header_byte(my_flags); /* general flags */ + /* magic header for gzip files: 1F 8B */ + /* compression method: 8 (DEFLATED) */ + /* general flags: 0 */ + put_32bit(0x00088b1f); put_32bit(time_stamp); /* Write deflated file to zip file */ - crc = ~0; + G1.crc = ~0; - bi_init(out); - ct_init(&attr, &method); + bi_init(); + ct_init(); lm_init(&deflate_flags); - put_8bit((uch) deflate_flags); /* extra flags */ + put_8bit(deflate_flags); /* extra flags */ put_8bit(3); /* OS identifier = 3 (Unix) */ deflate(); /* Write the crc and uncompressed size */ - put_32bit(~crc); - put_32bit(isize); + put_32bit(~G1.crc); + put_32bit(G1.isize); flush_outbuf(); +} + + +/* ======================================================================== */ +static +char* make_new_name_gzip(char *filename) +{ + return xasprintf("%s.gz", filename); +} + +static +USE_DESKTOP(long long) int pack_gzip(unpack_info_t *info UNUSED_PARAM) +{ + struct stat s; + + clear_bufs(); + s.st_ctime = 0; + fstat(STDIN_FILENO, &s); + zip(s.st_ctime); return 0; } + +/* + * Linux kernel build uses gzip -d -n. We accept and ignore it. + * Man page says: + * -n --no-name + * gzip: do not save the original file name and time stamp. + * (The original name is always saved if the name had to be truncated.) + * gunzip: do not restore the original file name/time even if present + * (remove only the gzip suffix from the compressed file name). + * This option is the default when decompressing. + * -N --name + * gzip: always save the original file name and time stamp (this is the default) + * gunzip: restore the original file name and time stamp if present. + */ + +int gzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +#if ENABLE_GUNZIP +int gzip_main(int argc, char **argv) +#else +int gzip_main(int argc UNUSED_PARAM, char **argv) +#endif +{ + unsigned opt; + + /* Must match bbunzip's constants OPT_STDOUT, OPT_FORCE! */ + opt = getopt32(argv, "cfv" USE_GUNZIP("dt") "q123456789n"); +#if ENABLE_GUNZIP /* gunzip_main may not be visible... */ + if (opt & 0x18) // -d and/or -t + return gunzip_main(argc, argv); +#endif + option_mask32 &= 0x7; /* ignore -q, -0..9 */ + //if (opt & 0x1) // -c + //if (opt & 0x2) // -f + //if (opt & 0x4) // -v + argv += optind; + + SET_PTR_TO_GLOBALS(xzalloc(sizeof(struct globals) + sizeof(struct globals2)) + + sizeof(struct globals)); + barrier(); + G2.l_desc.dyn_tree = G2.dyn_ltree; + G2.l_desc.static_tree = G2.static_ltree; + G2.l_desc.extra_bits = extra_lbits; + G2.l_desc.extra_base = LITERALS + 1; + G2.l_desc.elems = L_CODES; + G2.l_desc.max_length = MAX_BITS; + //G2.l_desc.max_code = 0; + + G2.d_desc.dyn_tree = G2.dyn_dtree; + G2.d_desc.static_tree = G2.static_dtree; + G2.d_desc.extra_bits = extra_dbits; + //G2.d_desc.extra_base = 0; + G2.d_desc.elems = D_CODES; + G2.d_desc.max_length = MAX_BITS; + //G2.d_desc.max_code = 0; + + G2.bl_desc.dyn_tree = G2.bl_tree; + //G2.bl_desc.static_tree = NULL; + G2.bl_desc.extra_bits = extra_blbits, + //G2.bl_desc.extra_base = 0; + G2.bl_desc.elems = BL_CODES; + G2.bl_desc.max_length = MAX_BL_BITS; + //G2.bl_desc.max_code = 0; + + /* Allocate all global buffers (for DYN_ALLOC option) */ + ALLOC(uch, G1.l_buf, INBUFSIZ); + ALLOC(uch, G1.outbuf, OUTBUFSIZ); + ALLOC(ush, G1.d_buf, DIST_BUFSIZE); + ALLOC(uch, G1.window, 2L * WSIZE); + ALLOC(ush, G1.prev, 1L << BITS); + + /* Initialise the CRC32 table */ + G1.crc_32_tab = crc32_filltable(NULL, 0); + + return bbunpack(argv, make_new_name_gzip, pack_gzip); +}