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diff --git a/i/pc104/initrd/conf/busybox/archival/gzip.c b/i/pc104/initrd/conf/busybox/archival/gzip.c
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+++ b/i/pc104/initrd/conf/busybox/archival/gzip.c
@@ -0,0 +1,2085 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Gzip implementation for busybox
+ *
+ * Based on GNU gzip Copyright (C) 1992-1993 Jean-loup Gailly.
+ *
+ * Originally adjusted for busybox by Charles P. Wright <cpw@unix.asb.com>
+ * "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 <andersen@codepoet.org> to support
+ * files as well as stdin/stdout, and to generally behave itself wrt
+ * command line handling.
+ *
+ * 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" should say:
+a: 85.1% -- replaced with a.gz
+gzip: bogus: No such file or directory
+aa: 85.1% -- replaced with aa.gz
+*/
+
+#include "busybox.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
+
+
+/* ===========================================================================
+ */
+#define SMALL_MEM
+
+#ifndef INBUFSIZ
+# ifdef SMALL_MEM
+# define INBUFSIZ 0x2000 /* input buffer size */
+# else
+# define INBUFSIZ 0x8000 /* input buffer size */
+# endif
+#endif
+
+#ifndef OUTBUFSIZ
+# ifdef SMALL_MEM
+# define OUTBUFSIZ 8192 /* output buffer size */
+# else
+# define OUTBUFSIZ 16384 /* output buffer size */
+# endif
+#endif
+
+#ifndef DIST_BUFSIZE
+# ifdef SMALL_MEM
+# define DIST_BUFSIZE 0x2000 /* buffer for distances, see trees.c */
+# else
+# define DIST_BUFSIZE 0x8000 /* buffer for distances, see trees.c */
+# endif
+#endif
+
+/* 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 */
+#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
+#define COMMENT 0x10 /* bit 4 set: file comment present */
+#define RESERVED 0xC0 /* bit 6,7: reserved */
+
+/* internal file attribute */
+#define UNKNOWN 0xffff
+#define BINARY 0
+#define ASCII 1
+
+#ifndef WSIZE
+# define WSIZE 0x8000 /* window size--must be a power of two, and */
+#endif /* at least 32K for zip's deflate method */
+
+#define MIN_MATCH 3
+#define MAX_MATCH 258
+/* The minimum and maximum match lengths */
+
+#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
+/* Minimum amount of lookahead, except at the end of the input file.
+ * See deflate.c for comments about the MIN_MATCH+1.
+ */
+
+#define MAX_DIST (WSIZE-MIN_LOOKAHEAD)
+/* In order to simplify the code, particularly on 16 bit machines, match
+ * distances are limited to MAX_DIST instead of WSIZE.
+ */
+
+#ifndef MAX_PATH_LEN
+# define MAX_PATH_LEN 1024 /* max pathname length */
+#endif
+
+#define seekable() 0 /* force sequential output */
+#define translate_eol 0 /* no option -a yet */
+
+#ifndef BITS
+# define BITS 16
+#endif
+#define INIT_BITS 9 /* Initial number of bits per code */
+
+#define BIT_MASK 0x1f /* Mask for 'number of compression bits' */
+/* Mask 0x20 is reserved to mean a fourth header byte, and 0x40 is free.
+ * It's a pity that old uncompress does not check bit 0x20. That makes
+ * extension of the format actually undesirable because old compress
+ * would just crash on the new format instead of giving a meaningful
+ * error message. It does check the number of bits, but it's more
+ * helpful to say "unsupported format, get a new version" than
+ * "can only handle 16 bits".
+ */
+
+#ifdef MAX_EXT_CHARS
+# define MAX_SUFFIX MAX_EXT_CHARS
+#else
+# define MAX_SUFFIX 30
+#endif
+
+
+/* ===========================================================================
+ * 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.
+ */
+
+#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<<HASH_BITS)
+#define HASH_MASK (HASH_SIZE-1)
+#define WMASK (WSIZE-1)
+/* HASH_SIZE and WSIZE must be powers of two */
+#ifndef TOO_FAR
+# define TOO_FAR 4096
+#endif
+/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
+
+
+/* ===========================================================================
+ * These types are not really 'char', 'short' and 'long'
+ */
+typedef uint8_t uch;
+typedef uint16_t ush;
+typedef uint32_t ulg;
+typedef int32_t lng;
+
+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.
+ */
+
+enum {
+ WINDOW_SIZE = 2 * WSIZE,
+/* window size, 2*WSIZE except for MMAP or BIG_MEM, where it is the
+ * input file length plus MIN_LOOKAHEAD.
+ */
+
+ 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.
+ */
+};
+
+
+struct globals {
+
+ lng block_start;
+
+/* 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 */
+
+#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
+ */
+
+ unsigned 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.
+ */
+
+ unsigned strstart; /* start of string to insert */
+ unsigned match_start; /* start of matching string */
+ unsigned lookahead; /* number of valid bytes ahead in window */
+
+/* ===========================================================================
+ */
+#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);
+
+/* 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);
+
+/* Heads of the hash chains or 0. */
+ /* DECLARE(Pos, head, 1<<HASH_BITS); */
+#define head (G1.prev + WSIZE) /* hash head (see deflate.c) */
+
+/* number of input bytes */
+ ulg isize; /* only 32 bits stored in .gz file */
+
+/* bbox always use stdin/stdout */
+#define ifd STDIN_FILENO /* input file descriptor */
+#define ofd STDOUT_FILENO /* output file descriptor */
+
+#ifdef DEBUG
+ unsigned insize; /* valid bytes in l_buf */
+#endif
+ unsigned outcnt; /* bytes in output buffer */
+
+ smallint eofile; /* flag set at end of input file */
+
+/* ===========================================================================
+ * Local data used by the "bit string" routines.
+ */
+
+ unsigned short bi_buf;
+
+/* Output buffer. bits are inserted starting at the bottom (least significant
+ * bits).
+ */
+
+#undef BUF_SIZE
+#define BUF_SIZE (8 * sizeof(G1.bi_buf))
+/* Number of bits used within bi_buf. (bi_buf might be implemented on
+ * more than 16 bits on some systems.)
+ */
+
+ int bi_valid;
+
+/* Current input function. Set to mem_read for in-memory compression */
+
+#ifdef DEBUG
+ ulg bits_sent; /* bit length of the compressed data */
+#endif
+
+ uint32_t *crc_32_tab;
+ uint32_t crc; /* shift register contents */
+};
+
+#define G1 (*(ptr_to_globals - 1))
+
+
+/* ===========================================================================
+ * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
+ * (used for the compressed data only)
+ */
+static void flush_outbuf(void)
+{
+ if (G1.outcnt == 0)
+ return;
+
+ xwrite(ofd, (char *) G1.outbuf, G1.outcnt);
+ G1.outcnt = 0;
+}
+
+
+/* ===========================================================================
+ */
+/* put_8bit is used for the compressed output */
+#define put_8bit(c) \
+do { \
+ G1.outbuf[G1.outcnt++] = (c); \
+ if (G1.outcnt == OUTBUFSIZ) flush_outbuf(); \
+} while (0)
+
+/* Output a 16 bit value, lsb first */
+static void put_16bit(ush w)
+{
+ if (G1.outcnt < OUTBUFSIZ - 2) {
+ G1.outbuf[G1.outcnt++] = w;
+ G1.outbuf[G1.outcnt++] = w >> 8;
+ } else {
+ put_8bit(w);
+ put_8bit(w >> 8);
+ }
+}
+
+static void put_32bit(ulg n)
+{
+ put_16bit(n);
+ put_16bit(n >> 16);
+}
+
+/* ===========================================================================
+ * Clear input and output buffers
+ */
+static void clear_bufs(void)
+{
+ G1.outcnt = 0;
+#ifdef DEBUG
+ G1.insize = 0;
+#endif
+ G1.isize = 0;
+}
+
+
+/* ===========================================================================
+ * Run a set of bytes through the crc shift register. If s is a NULL
+ * pointer, then initialize the crc shift register contents instead.
+ * Return the current crc in either case.
+ */
+static uint32_t updcrc(uch * s, unsigned n)
+{
+ uint32_t c = G1.crc;
+ while (n) {
+ c = G1.crc_32_tab[(uch)(c ^ *s++)] ^ (c >> 8);
+ n--;
+ }
+ G1.crc = c;
+ return c;
+}
+
+
+/* ===========================================================================
+ * Read a new buffer from the current input file, perform end-of-line
+ * translation, and update the crc and input file size.
+ * IN assertion: size >= 2 (for end-of-line translation)
+ */
+static unsigned file_read(void *buf, unsigned size)
+{
+ unsigned len;
+
+ 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);
+ G1.isize += len;
+ return len;
+}
+
+
+/* ===========================================================================
+ * Send a value on a given number of bits.
+ * IN assertion: length <= 16 and value fits in length bits.
+ */
+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");
+ 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 (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 {
+ 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)
+ * IN assertion: 1 <= len <= 15
+ */
+static unsigned bi_reverse(unsigned code, int len)
+{
+ unsigned res = 0;
+
+ while (1) {
+ res |= code & 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 (G1.bi_valid > 8) {
+ put_16bit(G1.bi_buf);
+ } else if (G1.bi_valid > 0) {
+ put_8bit(G1.bi_buf);
+ }
+ G1.bi_buf = 0;
+ G1.bi_valid = 0;
+#ifdef DEBUG
+ 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.
+ */
+static void copy_block(char *buf, unsigned len, int header)
+{
+ bi_windup(); /* align on byte boundary */
+
+ if (header) {
+ put_16bit(len);
+ put_16bit(~len);
+#ifdef DEBUG
+ G1.bits_sent += 2 * 16;
+#endif
+ }
+#ifdef DEBUG
+ G1.bits_sent += (ulg) len << 3;
+#endif
+ while (len--) {
+ put_8bit(*buf++);
+ }
+}
+
+
+/* ===========================================================================
+ * 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. */
+
+ /* 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;
+ }
+ }
+}
+
+
+/* ===========================================================================
+ * Set match_start to the longest match starting at the given string and
+ * return its length. Matches shorter or equal to prev_length are discarded,
+ * in which case the result is equal to prev_length and match_start is
+ * garbage.
+ * IN assertions: cur_match is the head of the hash chain for the current
+ * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 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 = 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.
+ */
+#if HASH_BITS < 8 || MAX_MATCH != 258
+# error Code too clever
+#endif
+ 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 (G1.prev_length >= good_match) {
+ chain_length >>= 2;
+ }
+ Assert(G1.strstart <= WINDOW_SIZE - MIN_LOOKAHEAD, "insufficient lookahead");
+
+ do {
+ 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:
+ */
+ if (match[best_len] != scan_end ||
+ match[best_len - 1] != scan_end1 ||
+ *match != *scan || *++match != scan[1])
+ continue;
+
+ /* The check at best_len-1 can be removed because it will be made
+ * again later. (This heuristic is not always a win.)
+ * It is not necessary to compare scan[2] and match[2] since they
+ * are always equal when the other bytes match, given that
+ * the hash keys are equal and that HASH_BITS >= 8.
+ */
+ scan += 2, match++;
+
+ /* We check for insufficient lookahead only every 8th comparison;
+ * the 256th check will be made at strstart+258.
+ */
+ do {
+ } while (*++scan == *++match && *++scan == *++match &&
+ *++scan == *++match && *++scan == *++match &&
+ *++scan == *++match && *++scan == *++match &&
+ *++scan == *++match && *++scan == *++match && scan < strend);
+
+ len = MAX_MATCH - (int) (strend - scan);
+ scan = strend - MAX_MATCH;
+
+ if (len > best_len) {
+ 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 = 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.
+ */
+static void check_match(IPos start, IPos match, int length)
+{
+ /* check that the match is indeed a match */
+ 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(G1.window[start++], stderr);
+ } while (--length != 0);
+ }
+}
+#else
+# define check_match(start, match, length) ((void)0)
+#endif
+
+
+/* trees.c -- output deflated data using Huffman coding
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/* 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.
+ *
+ * Each code tree is stored in the ZIP file in a compressed form
+ * which is itself a Huffman encoding of the lengths of
+ * all the code strings (in ascending order by source values).
+ * The actual code strings are reconstructed from the lengths in
+ * the UNZIP process, as described in the "application note"
+ * (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.
+ *
+ * Storer, James A.
+ * Data Compression: Methods and Theory, pp. 49-50.
+ * Computer Science Press, 1988. ISBN 0-7167-8156-5.
+ *
+ * Sedgewick, R.
+ * Algorithms, p290.
+ * Addison-Wesley, 1983. ISBN 0-201-06672-6.
+ *
+ * INTERFACE
+ * 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) -- deleted in bbox]
+ *
+ * void ct_tally(int dist, int lc);
+ * Save the match info and tally the frequency counts.
+ *
+ * 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.
+ */
+
+#define MAX_BITS 15
+/* All codes must not exceed MAX_BITS bits */
+
+#define MAX_BL_BITS 7
+/* Bit length codes must not exceed MAX_BL_BITS bits */
+
+#define LENGTH_CODES 29
+/* number of length codes, not counting the special END_BLOCK code */
+
+#define LITERALS 256
+/* number of literal bytes 0..255 */
+
+#define END_BLOCK 256
+/* end of block literal code */
+
+#define L_CODES (LITERALS+1+LENGTH_CODES)
+/* number of Literal or Length codes, including the END_BLOCK code */
+
+#define D_CODES 30
+/* number of distance codes */
+
+#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,
+ 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,
+ 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 };
+
+/* 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 };
+
+#define STORED_BLOCK 0
+#define STATIC_TREES 1
+#define DYN_TREES 2
+/* The three kinds of block type */
+
+#ifndef LIT_BUFSIZE
+# ifdef SMALL_MEM
+# define LIT_BUFSIZE 0x2000
+# else
+# ifdef MEDIUM_MEM
+# define LIT_BUFSIZE 0x4000
+# else
+# define LIT_BUFSIZE 0x8000
+# endif
+# endif
+#endif
+#ifndef DIST_BUFSIZE
+# define DIST_BUFSIZE LIT_BUFSIZE
+#endif
+/* Sizes of match buffers for literals/lengths and distances. There are
+ * 4 reasons for limiting LIT_BUFSIZE to 64K:
+ * - frequencies can be kept in 16 bit counters
+ * - if compression is not successful for the first block, all input data is
+ * still in the window so we can still emit a stored block even when input
+ * comes from standard input. (This can also be done for all blocks if
+ * LIT_BUFSIZE is not greater than 32K.)
+ * - if compression is not successful for a file smaller than 64K, we can
+ * even emit a stored file instead of a stored block (saving 5 bytes).
+ * - creating new Huffman trees less frequently may not provide fast
+ * adaptation to changes in the input data statistics. (Take for
+ * example a binary file with poorly compressible code followed by
+ * a highly compressible string table.) Smaller buffer sizes give
+ * fast adaptation but have of course the overhead of transmitting trees
+ * more frequently.
+ * - I can't count above 4
+ * The current code is general and allows DIST_BUFSIZE < LIT_BUFSIZE (to save
+ * memory at the expense of compression). Some optimizations would be possible
+ * if we rely on DIST_BUFSIZE == LIT_BUFSIZE.
+ */
+#define REP_3_6 16
+/* repeat previous bit length 3-6 times (2 bits of repeat count) */
+#define REPZ_3_10 17
+/* repeat a zero length 3-10 times (3 bits of repeat count) */
+#define REPZ_11_138 18
+/* repeat a zero length 11-138 times (7 bits of repeat count) */
+
+/* ===========================================================================
+*/
+/* Data structure describing a single value and its code string. */
+typedef struct ct_data {
+ union {
+ ush freq; /* frequency count */
+ ush code; /* bit string */
+ } fc;
+ union {
+ ush dad; /* father node in Huffman tree */
+ ush len; /* length of bit string */
+ } dl;
+} ct_data;
+
+#define Freq fc.freq
+#define Code fc.code
+#define Dad dl.dad
+#define Len dl.len
+
+#define HEAP_SIZE (2*L_CODES + 1)
+/* maximum heap size */
+
+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;
+
+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 */
+
+/* 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
+ * The codes 286 and 287 are needed to build a canonical tree (see ct_init
+ * below).
+ */
+
+ ct_data static_dtree[D_CODES];
+
+/* The static distance tree. (Actually a trivial tree since all codes use
+ * 5 bits.)
+ */
+
+ ct_data bl_tree[2 * BL_CODES + 1];
+
+/* Huffman tree for the bit lengths */
+
+ tree_desc l_desc;
+ tree_desc d_desc;
+ tree_desc bl_desc;
+
+ 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.
+ */
+
+ uch depth[2 * L_CODES + 1];
+
+/* Depth of each subtree used as tie breaker for trees of equal frequency */
+
+ uch length_code[MAX_MATCH - MIN_MATCH + 1];
+
+/* length code for each normalized match length (0 == MIN_MATCH) */
+
+ 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.
+ */
+
+ int base_length[LENGTH_CODES];
+
+/* First normalized length for each code (0 = MIN_MATCH) */
+
+ int base_dist[D_CODES];
+
+/* First normalized distance for each code (0 = distance of 1) */
+
+ 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.
+ */
+
+ 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.
+ */
+
+ ulg opt_len; /* bit length of current block with optimal trees */
+ ulg static_len; /* bit length of current block with static trees */
+
+ ulg compressed_len; /* total bit length of compressed file */
+};
+
+#define G2ptr ((struct globals2*)(ptr_to_globals))
+#define G2 (*G2ptr)
+
+
+/* ===========================================================================
+ */
+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);
+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);
+
+
+#ifndef DEBUG
+/* 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 ? 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.
+ */
+
+
+/* ===========================================================================
+ * Initialize a new block.
+ */
+static void init_block(void)
+{
+ int n; /* iterates over tree elements */
+
+ /* Initialize the trees. */
+ for (n = 0; n < L_CODES; n++)
+ G2.dyn_ltree[n].Freq = 0;
+ for (n = 0; n < D_CODES; n++)
+ G2.dyn_dtree[n].Freq = 0;
+ for (n = 0; n < BL_CODES; n++)
+ G2.bl_tree[n].Freq = 0;
+
+ 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;
+}
+
+
+/* ===========================================================================
+ * Restore the heap property by moving down the tree starting at node k,
+ * exchanging a node with the smallest of its two sons if necessary, stopping
+ * 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 = G2.heap[k];
+ int j = k << 1; /* left son of k */
+
+ while (j <= G2.heap_len) {
+ /* Set j to the smallest of the two sons: */
+ 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, G2.heap[j]))
+ break;
+
+ /* Exchange v with the smallest son */
+ G2.heap[k] = G2.heap[j];
+ k = j;
+
+ /* And continue down the tree, setting j to the left son of k */
+ j <<= 1;
+ }
+ G2.heap[k] = v;
+}
+
+
+/* ===========================================================================
+ * Compute the optimal bit lengths for a tree and update the total bit length
+ * for the current block.
+ * IN assertion: the fields freq and dad are set, heap[heap_max] and
+ * above are the tree nodes sorted by increasing frequency.
+ * OUT assertions: the field len is set to the optimal bit length, the
+ * array bl_count contains the frequencies for each bit length.
+ * The length opt_len is updated; static_len is also updated if stree is
+ * not null.
+ */
+static void gen_bitlen(tree_desc * desc)
+{
+ ct_data *tree = desc->dyn_tree;
+ const extra_bits_t *extra = desc->extra_bits;
+ int base = desc->extra_base;
+ int max_code = desc->max_code;
+ int max_length = desc->max_length;
+ ct_data *stree = desc->static_tree;
+ int h; /* heap index */
+ int n, m; /* iterate over the tree elements */
+ int bits; /* bit length */
+ int xbits; /* extra bits */
+ ush f; /* frequency */
+ int overflow = 0; /* number of elements with bit length too large */
+
+ for (bits = 0; bits <= MAX_BITS; bits++)
+ 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[G2.heap[G2.heap_max]].Len = 0; /* root of the heap */
+
+ 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++;
+ }
+ tree[n].Len = (ush) bits;
+ /* We overwrite tree[n].Dad which is no longer needed */
+
+ if (n > max_code)
+ continue; /* not a leaf node */
+
+ G2.bl_count[bits]++;
+ xbits = 0;
+ if (n >= base)
+ xbits = extra[n - base];
+ f = tree[n].Freq;
+ G2.opt_len += (ulg) f *(bits + xbits);
+
+ if (stree)
+ G2.static_len += (ulg) f * (stree[n].Len + xbits);
+ }
+ if (overflow == 0)
+ return;
+
+ Trace((stderr, "\nbit length overflow\n"));
+ /* This happens for example on obj2 and pic of the Calgary corpus */
+
+ /* Find the first bit length which could increase: */
+ do {
+ bits = max_length - 1;
+ while (G2.bl_count[bits] == 0)
+ bits--;
+ 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]
+ */
+ overflow -= 2;
+ } while (overflow > 0);
+
+ /* Now recompute all bit lengths, scanning in increasing frequency.
+ * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
+ * lengths instead of fixing only the wrong ones. This idea is taken
+ * from 'ar' written by Haruhiko Okumura.)
+ */
+ for (bits = max_length; bits != 0; bits--) {
+ n = G2.bl_count[bits];
+ while (n != 0) {
+ 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));
+ 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).
+ * IN assertion: the array bl_count contains the bit length statistics for
+ * the given tree and the field len is set for all tree elements.
+ * OUT assertion: the field code is set for all tree elements of non
+ * zero code length.
+ */
+static void gen_codes(ct_data * tree, int max_code)
+{
+ ush next_code[MAX_BITS + 1]; /* next code value for each bit length */
+ ush code = 0; /* running code value */
+ int bits; /* bit index */
+ int n; /* code index */
+
+ /* The distribution counts are first used to generate the code values
+ * without bit reversal.
+ */
+ for (bits = 1; bits <= MAX_BITS; bits++) {
+ 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 + G2.bl_count[MAX_BITS] - 1 == (1 << MAX_BITS) - 1,
+ "inconsistent bit counts");
+ Tracev((stderr, "\ngen_codes: max_code %d ", max_code));
+
+ for (n = 0; n <= max_code; n++) {
+ int len = tree[n].Len;
+
+ if (len == 0)
+ continue;
+ /* Now reverse the bits */
+ tree[n].Code = bi_reverse(next_code[len]++, len);
+
+ 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.
+ * IN assertion: the field freq is set for all tree elements.
+ * OUT assertions: the fields len and code are set to the optimal bit length
+ * 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;
+ ct_data *stree = desc->static_tree;
+ int elems = desc->elems;
+ int n, m; /* iterate over heap elements */
+ int max_code = -1; /* largest code with non zero frequency */
+ int node = elems; /* next internal node of the tree */
+
+ /* Construct the initial heap, with least frequent element in
+ * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
+ * heap[0] is not used.
+ */
+ G2.heap_len = 0;
+ G2.heap_max = HEAP_SIZE;
+
+ for (n = 0; n < elems; n++) {
+ if (tree[n].Freq != 0) {
+ G2.heap[++G2.heap_len] = max_code = n;
+ G2.depth[n] = 0;
+ } else {
+ tree[n].Len = 0;
+ }
+ }
+
+ /* The pkzip format requires that at least one distance code exists,
+ * and that at least one bit should be sent even if there is only one
+ * possible code. So to avoid special checks later on we force at least
+ * two codes of non zero frequency.
+ */
+ while (G2.heap_len < 2) {
+ int new = G2.heap[++G2.heap_len] = (max_code < 2 ? ++max_code : 0);
+
+ tree[new].Freq = 1;
+ G2.depth[new] = 0;
+ G2.opt_len--;
+ if (stree)
+ G2.static_len -= stree[new].Len;
+ /* new is 0 or 1 so it does not have extra bits */
+ }
+ desc->max_code = max_code;
+
+ /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
+ * establish sub-heaps of increasing lengths:
+ */
+ 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 = G2.heap[SMALLEST]; /* m = node of next least frequency */
+
+ 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;
+ 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 == 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 */
+ G2.heap[SMALLEST] = node++;
+ pqdownheap(tree, SMALLEST);
+
+ } while (G2.heap_len >= 2);
+
+ 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.
+ */
+ gen_bitlen((tree_desc *) desc);
+
+ /* The field len is now set, we can generate the bit codes */
+ 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
+ * counts. (The contribution of the bit length codes will be added later
+ * during the construction of bl_tree.)
+ */
+static void scan_tree(ct_data * tree, int max_code)
+{
+ int n; /* iterates over all tree elements */
+ int prevlen = -1; /* last emitted length */
+ int curlen; /* length of current code */
+ int nextlen = tree[0].Len; /* length of next code */
+ int count = 0; /* repeat count of the current 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 = 0xffff; /* guard */
+
+ for (n = 0; n <= max_code; n++) {
+ curlen = nextlen;
+ nextlen = tree[n + 1].Len;
+ if (++count < max_count && curlen == nextlen)
+ continue;
+
+ if (count < min_count) {
+ G2.bl_tree[curlen].Freq += count;
+ } else if (curlen != 0) {
+ if (curlen != prevlen)
+ G2.bl_tree[curlen].Freq++;
+ G2.bl_tree[REP_3_6].Freq++;
+ } else if (count <= 10) {
+ G2.bl_tree[REPZ_3_10].Freq++;
+ } else {
+ 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;
+ } else if (curlen == nextlen) {
+ max_count = 6;
+ min_count = 3;
+ }
+ }
+}
+
+
+/* ===========================================================================
+ * Send a literal or distance tree in compressed form, using the codes in
+ * bl_tree.
+ */
+static void send_tree(ct_data * tree, int max_code)
+{
+ int n; /* iterates over all tree elements */
+ int prevlen = -1; /* last emitted length */
+ int curlen; /* length of current code */
+ int nextlen = tree[0].Len; /* length of next code */
+ int count = 0; /* repeat count of the current code */
+ int max_count = 7; /* max repeat count */
+ int min_count = 4; /* min repeat count */
+
+/* tree[max_code+1].Len = -1; *//* guard already set */
+ if (nextlen == 0)
+ max_count = 138, min_count = 3;
+
+ for (n = 0; n <= max_code; n++) {
+ curlen = nextlen;
+ nextlen = tree[n + 1].Len;
+ if (++count < max_count && curlen == nextlen) {
+ continue;
+ } else if (count < min_count) {
+ do {
+ SEND_CODE(curlen, G2.bl_tree);
+ } while (--count);
+ } else if (curlen != 0) {
+ if (curlen != prevlen) {
+ SEND_CODE(curlen, G2.bl_tree);
+ count--;
+ }
+ Assert(count >= 3 && count <= 6, " 3_6?");
+ SEND_CODE(REP_3_6, G2.bl_tree);
+ send_bits(count - 3, 2);
+ } else if (count <= 10) {
+ SEND_CODE(REPZ_3_10, G2.bl_tree);
+ send_bits(count - 3, 3);
+ } else {
+ 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;
+ } else if (curlen == nextlen) {
+ max_count = 6;
+ min_count = 3;
+ } else {
+ 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.
+ */
+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(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(&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.
+ */
+
+ /* Determine the number of bit length codes to send. The pkzip format
+ * requires that at least 4 bit length codes be sent. (appnote.txt says
+ * 3 but the actual value used is 4.)
+ */
+ for (max_blindex = BL_CODES - 1; max_blindex >= 3; max_blindex--) {
+ if (G2.bl_tree[bl_order[max_blindex]].Len != 0)
+ break;
+ }
+ /* Update opt_len to include the bit length tree and counts */
+ 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.
+ * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
+ */
+static void send_all_trees(int lcodes, int dcodes, int blcodes)
+{
+ int rank; /* index in bl_order */
+
+ Assert(lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
+ Assert(lcodes <= L_CODES && dcodes <= D_CODES
+ && blcodes <= BL_CODES, "too many codes");
+ Tracev((stderr, "\nbl counts: "));
+ send_bits(lcodes - 257, 5); /* not +255 as stated in appnote.txt */
+ send_bits(dcodes - 1, 5);
+ 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(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;
+ }
+ 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 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_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
+ * returns the total compressed length for the file so far.
+ */
+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 */
+
+ G2.flag_buf[G2.last_flags] = G2.flags; /* Save the flags for the last 8 items */
+
+ /* Construct the literal and distance trees */
+ build_tree(&G2.l_desc);
+ Tracev((stderr, "\nlit data: dyn %ld, stat %ld", G2.opt_len, G2.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.
+ */
+
+ /* Build the bit length tree for the above two trees, and get the index
+ * in bl_order of the last bit length code to send.
+ */
+ max_blindex = build_bl_tree();
+
+ /* Determine the best encoding. Compute first the block length in bytes */
+ 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, 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;
+
+ /* If compression failed and this is the first and last block,
+ * 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 && G2.compressed_len == 0L && seekable()) {
+ /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
+ if (buf == NULL)
+ bb_error_msg("block vanished");
+
+ copy_block(buf, (unsigned) stored_len, 0); /* without header */
+ G2.compressed_len = stored_len << 3;
+
+ } 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
+ * the last block flush, because compression would have been
+ * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
+ * transform a block into a stored block.
+ */
+ send_bits((STORED_BLOCK << 1) + eof, 3); /* send block type */
+ 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 *) 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(G2.l_desc.max_code + 1, G2.d_desc.max_code + 1,
+ max_blindex + 1);
+ compress_block((ct_data *) G2.dyn_ltree, (ct_data *) G2.dyn_dtree);
+ G2.compressed_len += 3 + G2.opt_len;
+ }
+ Assert(G2.compressed_len == G1.bits_sent, "bad compressed size");
+ init_block();
+
+ if (eof) {
+ bi_windup();
+ G2.compressed_len += 7; /* align on byte boundary */
+ }
+ Tracev((stderr, "\ncomprlen %lu(%lu) ", G2.compressed_len >> 3,
+ G2.compressed_len - 7 * eof));
+
+ return G2.compressed_len >> 3;
+}
+
+
+/* ===========================================================================
+ * 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)<<H_SHIFT) ^ (c)) & HASH_MASK)
+
+
+/* ===========================================================================
+ * 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.
+ */
+
+/* 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( \
+ G1.block_start >= 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)
+{
+ 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 (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);
+
+ /* Find the longest match, discarding those <= prev_length.
+ */
+ G1.prev_length = match_length;
+ prev_match = G1.match_start;
+ match_length = MIN_MATCH - 1;
+
+ 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;
+
+ /* 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--;
+ }
+ }
+ /* 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();
+ }
+ if (match_available)
+ ct_tally(0, G1.window[G1.strstart - 1]);
+
+ return FLUSH_BLOCK(1); /* eof */
+}
+
+
+/* ===========================================================================
+ * Initialize the bit string routines.
+ */
+static void bi_init(void)
+{
+ 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.
+ */
+}
+
+
+/* ===========================================================================
+ * 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 ct_init(void)
+{
+ 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.
+ */
+
+static void zip(ulg time_stamp)
+{
+ ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */
+
+ G1.outcnt = 0;
+
+ /* Write the header to the gzip file. See algorithm.doc for the format */
+ /* 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 */
+ G1.crc = ~0;
+
+ bi_init();
+ ct_init();
+ lm_init(&deflate_flags);
+
+ put_8bit(deflate_flags); /* extra flags */
+ put_8bit(3); /* OS identifier = 3 (Unix) */
+
+ deflate();
+
+ /* Write the crc and uncompressed size */
+ 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(void)
+{
+ struct stat s;
+
+ clear_bufs();
+ s.st_ctime = 0;
+ fstat(STDIN_FILENO, &s);
+ zip(s.st_ctime);
+ return 0;
+}
+
+int gzip_main(int argc, char **argv);
+int gzip_main(int argc, char **argv)
+{
+ unsigned opt;
+
+ /* Must match bbunzip's constants OPT_STDOUT, OPT_FORCE! */
+ opt = getopt32(argc, argv, "cfv" USE_GUNZIP("d") "q123456789" );
+ option_mask32 &= 0x7; /* Clear -d, ignore -q, -0..9 */
+ //if (opt & 0x1) // -c
+ //if (opt & 0x2) // -f
+ //if (opt & 0x4) // -v
+#if ENABLE_GUNZIP /* gunzip_main may not be visible... */
+ if (opt & 0x8) { // -d
+ return gunzip_main(argc, argv);
+ }
+#endif
+ argv += optind;
+
+ PTR_TO_GLOBALS = xzalloc(sizeof(struct globals) + sizeof(struct globals2))
+ + sizeof(struct globals);
+ 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(0);
+
+ return bbunpack(argv, make_new_name_gzip, pack_gzip);
+}