Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/lib/zlib_deflate/Makefile b/lib/zlib_deflate/Makefile
new file mode 100644
index 0000000..86275e3
--- /dev/null
+++ b/lib/zlib_deflate/Makefile
@@ -0,0 +1,11 @@
+#
+# This is a modified version of zlib, which does all memory
+# allocation ahead of time.
+#
+# This is the compression code, see zlib_inflate for the
+# decompression code.
+#
+
+obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate.o
+
+zlib_deflate-objs := deflate.o deftree.o deflate_syms.o
diff --git a/lib/zlib_deflate/deflate.c b/lib/zlib_deflate/deflate.c
new file mode 100644
index 0000000..ad9a1bf
--- /dev/null
+++ b/lib/zlib_deflate/deflate.c
@@ -0,0 +1,1268 @@
+/* +++ deflate.c */
+/* deflate.c -- compress data using the deflation algorithm
+ * Copyright (C) 1995-1996 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * ALGORITHM
+ *
+ * The "deflation" process depends on being able to identify portions
+ * of the input text which are identical to earlier input (within a
+ * sliding window trailing behind the input currently being processed).
+ *
+ * The most straightforward technique turns out to be the fastest for
+ * most input files: try all possible matches and select the longest.
+ * The key feature of this algorithm is that insertions into the string
+ * dictionary are very simple and thus fast, and deletions are avoided
+ * completely. Insertions are performed at each input character, whereas
+ * string matches are performed only when the previous match ends. So it
+ * is preferable to spend more time in matches to allow very fast string
+ * insertions and avoid deletions. The matching algorithm for small
+ * strings is inspired from that of Rabin & Karp. A brute force approach
+ * is used to find longer strings when a small match has been found.
+ * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze
+ * (by Leonid Broukhis).
+ * A previous version of this file used a more sophisticated algorithm
+ * (by Fiala and Greene) which is guaranteed to run in linear amortized
+ * time, but has a larger average cost, uses more memory and is patented.
+ * However the F&G algorithm may be faster for some highly redundant
+ * files if the parameter max_chain_length (described below) is too large.
+ *
+ * ACKNOWLEDGEMENTS
+ *
+ * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and
+ * I found it in 'freeze' written by Leonid Broukhis.
+ * Thanks to many people for bug reports and testing.
+ *
+ * REFERENCES
+ *
+ * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".
+ * Available in ftp://ds.internic.net/rfc/rfc1951.txt
+ *
+ * A description of the Rabin and Karp algorithm is given in the book
+ * "Algorithms" by R. Sedgewick, Addison-Wesley, p252.
+ *
+ * Fiala,E.R., and Greene,D.H.
+ * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/zutil.h>
+#include "defutil.h"
+
+
+/* ===========================================================================
+ * Function prototypes.
+ */
+typedef enum {
+ need_more, /* block not completed, need more input or more output */
+ block_done, /* block flush performed */
+ finish_started, /* finish started, need only more output at next deflate */
+ finish_done /* finish done, accept no more input or output */
+} block_state;
+
+typedef block_state (*compress_func) (deflate_state *s, int flush);
+/* Compression function. Returns the block state after the call. */
+
+static void fill_window (deflate_state *s);
+static block_state deflate_stored (deflate_state *s, int flush);
+static block_state deflate_fast (deflate_state *s, int flush);
+static block_state deflate_slow (deflate_state *s, int flush);
+static void lm_init (deflate_state *s);
+static void putShortMSB (deflate_state *s, uInt b);
+static void flush_pending (z_streamp strm);
+static int read_buf (z_streamp strm, Byte *buf, unsigned size);
+static uInt longest_match (deflate_state *s, IPos cur_match);
+
+#ifdef DEBUG_ZLIB
+static void check_match (deflate_state *s, IPos start, IPos match,
+ int length);
+#endif
+
+/* ===========================================================================
+ * Local data
+ */
+
+#define NIL 0
+/* Tail of hash chains */
+
+#ifndef TOO_FAR
+# define TOO_FAR 4096
+#endif
+/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
+
+#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.
+ */
+
+/* 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.
+ */
+typedef struct config_s {
+ ush good_length; /* reduce lazy search above this match length */
+ ush max_lazy; /* do not perform lazy search above this match length */
+ ush nice_length; /* quit search above this match length */
+ ush max_chain;
+ compress_func func;
+} config;
+
+static const config configuration_table[10] = {
+/* good lazy nice chain */
+/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */
+/* 1 */ {4, 4, 8, 4, deflate_fast}, /* maximum speed, no lazy matches */
+/* 2 */ {4, 5, 16, 8, deflate_fast},
+/* 3 */ {4, 6, 32, 32, deflate_fast},
+
+/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */
+/* 5 */ {8, 16, 32, 32, deflate_slow},
+/* 6 */ {8, 16, 128, 128, deflate_slow},
+/* 7 */ {8, 32, 128, 256, deflate_slow},
+/* 8 */ {32, 128, 258, 1024, deflate_slow},
+/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* maximum compression */
+
+/* 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 */
+
+/* ===========================================================================
+ * 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(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)
+
+
+/* ===========================================================================
+ * Insert string str 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 str are valid
+ * (except for the last MIN_MATCH-1 bytes of the input file).
+ */
+#define INSERT_STRING(s, str, match_head) \
+ (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
+ s->prev[(str) & s->w_mask] = match_head = s->head[s->ins_h], \
+ s->head[s->ins_h] = (Pos)(str))
+
+/* ===========================================================================
+ * Initialize the hash table (avoiding 64K overflow for 16 bit systems).
+ * prev[] will be initialized on the fly.
+ */
+#define CLEAR_HASH(s) \
+ s->head[s->hash_size-1] = NIL; \
+ memset((char *)s->head, 0, (unsigned)(s->hash_size-1)*sizeof(*s->head));
+
+/* ========================================================================= */
+int zlib_deflateInit_(
+ z_streamp strm,
+ int level,
+ const char *version,
+ int stream_size
+)
+{
+ return zlib_deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS,
+ DEF_MEM_LEVEL,
+ Z_DEFAULT_STRATEGY, version, stream_size);
+ /* To do: ignore strm->next_in if we use it as window */
+}
+
+/* ========================================================================= */
+int zlib_deflateInit2_(
+ z_streamp strm,
+ int level,
+ int method,
+ int windowBits,
+ int memLevel,
+ int strategy,
+ const char *version,
+ int stream_size
+)
+{
+ deflate_state *s;
+ int noheader = 0;
+ static char* my_version = ZLIB_VERSION;
+ deflate_workspace *mem;
+
+ ush *overlay;
+ /* We overlay pending_buf and d_buf+l_buf. This works since the average
+ * output size for (length,distance) codes is <= 24 bits.
+ */
+
+ if (version == NULL || version[0] != my_version[0] ||
+ stream_size != sizeof(z_stream)) {
+ return Z_VERSION_ERROR;
+ }
+ if (strm == NULL) return Z_STREAM_ERROR;
+
+ strm->msg = NULL;
+
+ if (level == Z_DEFAULT_COMPRESSION) level = 6;
+
+ mem = (deflate_workspace *) strm->workspace;
+
+ if (windowBits < 0) { /* undocumented feature: suppress zlib header */
+ noheader = 1;
+ windowBits = -windowBits;
+ }
+ if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
+ windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
+ strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
+ return Z_STREAM_ERROR;
+ }
+ s = (deflate_state *) &(mem->deflate_memory);
+ strm->state = (struct internal_state *)s;
+ s->strm = strm;
+
+ s->noheader = noheader;
+ s->w_bits = windowBits;
+ s->w_size = 1 << s->w_bits;
+ s->w_mask = s->w_size - 1;
+
+ s->hash_bits = memLevel + 7;
+ s->hash_size = 1 << s->hash_bits;
+ s->hash_mask = s->hash_size - 1;
+ s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
+
+ s->window = (Byte *) mem->window_memory;
+ s->prev = (Pos *) mem->prev_memory;
+ s->head = (Pos *) mem->head_memory;
+
+ s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
+
+ overlay = (ush *) mem->overlay_memory;
+ s->pending_buf = (uch *) overlay;
+ s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
+
+ s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
+ s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
+
+ s->level = level;
+ s->strategy = strategy;
+ s->method = (Byte)method;
+
+ return zlib_deflateReset(strm);
+}
+
+/* ========================================================================= */
+int zlib_deflateSetDictionary(
+ z_streamp strm,
+ const Byte *dictionary,
+ uInt dictLength
+)
+{
+ deflate_state *s;
+ uInt length = dictLength;
+ uInt n;
+ IPos hash_head = 0;
+
+ if (strm == NULL || strm->state == NULL || dictionary == NULL)
+ return Z_STREAM_ERROR;
+
+ s = (deflate_state *) strm->state;
+ if (s->status != INIT_STATE) return Z_STREAM_ERROR;
+
+ strm->adler = zlib_adler32(strm->adler, dictionary, dictLength);
+
+ if (length < MIN_MATCH) return Z_OK;
+ if (length > MAX_DIST(s)) {
+ length = MAX_DIST(s);
+#ifndef USE_DICT_HEAD
+ dictionary += dictLength - length; /* use the tail of the dictionary */
+#endif
+ }
+ memcpy((char *)s->window, dictionary, length);
+ s->strstart = length;
+ s->block_start = (long)length;
+
+ /* Insert all strings in the hash table (except for the last two bytes).
+ * s->lookahead stays null, so s->ins_h will be recomputed at the next
+ * call of fill_window.
+ */
+ s->ins_h = s->window[0];
+ UPDATE_HASH(s, s->ins_h, s->window[1]);
+ for (n = 0; n <= length - MIN_MATCH; n++) {
+ INSERT_STRING(s, n, hash_head);
+ }
+ if (hash_head) hash_head = 0; /* to make compiler happy */
+ return Z_OK;
+}
+
+/* ========================================================================= */
+int zlib_deflateReset(
+ z_streamp strm
+)
+{
+ deflate_state *s;
+
+ if (strm == NULL || strm->state == NULL)
+ return Z_STREAM_ERROR;
+
+ strm->total_in = strm->total_out = 0;
+ strm->msg = NULL;
+ strm->data_type = Z_UNKNOWN;
+
+ s = (deflate_state *)strm->state;
+ s->pending = 0;
+ s->pending_out = s->pending_buf;
+
+ if (s->noheader < 0) {
+ s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */
+ }
+ s->status = s->noheader ? BUSY_STATE : INIT_STATE;
+ strm->adler = 1;
+ s->last_flush = Z_NO_FLUSH;
+
+ zlib_tr_init(s);
+ lm_init(s);
+
+ return Z_OK;
+}
+
+/* ========================================================================= */
+int zlib_deflateParams(
+ z_streamp strm,
+ int level,
+ int strategy
+)
+{
+ deflate_state *s;
+ compress_func func;
+ int err = Z_OK;
+
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ s = (deflate_state *) strm->state;
+
+ if (level == Z_DEFAULT_COMPRESSION) {
+ level = 6;
+ }
+ if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
+ return Z_STREAM_ERROR;
+ }
+ func = configuration_table[s->level].func;
+
+ if (func != configuration_table[level].func && strm->total_in != 0) {
+ /* Flush the last buffer: */
+ err = zlib_deflate(strm, Z_PARTIAL_FLUSH);
+ }
+ if (s->level != level) {
+ s->level = level;
+ s->max_lazy_match = configuration_table[level].max_lazy;
+ s->good_match = configuration_table[level].good_length;
+ s->nice_match = configuration_table[level].nice_length;
+ s->max_chain_length = configuration_table[level].max_chain;
+ }
+ s->strategy = strategy;
+ return err;
+}
+
+/* =========================================================================
+ * Put a short in the pending buffer. The 16-bit value is put in MSB order.
+ * IN assertion: the stream state is correct and there is enough room in
+ * pending_buf.
+ */
+static void putShortMSB(
+ deflate_state *s,
+ uInt b
+)
+{
+ put_byte(s, (Byte)(b >> 8));
+ put_byte(s, (Byte)(b & 0xff));
+}
+
+/* =========================================================================
+ * Flush as much pending output as possible. All deflate() output goes
+ * through this function so some applications may wish to modify it
+ * to avoid allocating a large strm->next_out buffer and copying into it.
+ * (See also read_buf()).
+ */
+static void flush_pending(
+ z_streamp strm
+)
+{
+ deflate_state *s = (deflate_state *) strm->state;
+ unsigned len = s->pending;
+
+ if (len > strm->avail_out) len = strm->avail_out;
+ if (len == 0) return;
+
+ if (strm->next_out != NULL) {
+ memcpy(strm->next_out, s->pending_out, len);
+ strm->next_out += len;
+ }
+ s->pending_out += len;
+ strm->total_out += len;
+ strm->avail_out -= len;
+ s->pending -= len;
+ if (s->pending == 0) {
+ s->pending_out = s->pending_buf;
+ }
+}
+
+/* ========================================================================= */
+int zlib_deflate(
+ z_streamp strm,
+ int flush
+)
+{
+ int old_flush; /* value of flush param for previous deflate call */
+ deflate_state *s;
+
+ if (strm == NULL || strm->state == NULL ||
+ flush > Z_FINISH || flush < 0) {
+ return Z_STREAM_ERROR;
+ }
+ s = (deflate_state *) strm->state;
+
+ if ((strm->next_in == NULL && strm->avail_in != 0) ||
+ (s->status == FINISH_STATE && flush != Z_FINISH)) {
+ return Z_STREAM_ERROR;
+ }
+ if (strm->avail_out == 0) return Z_BUF_ERROR;
+
+ s->strm = strm; /* just in case */
+ old_flush = s->last_flush;
+ s->last_flush = flush;
+
+ /* Write the zlib header */
+ if (s->status == INIT_STATE) {
+
+ uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
+ uInt level_flags = (s->level-1) >> 1;
+
+ if (level_flags > 3) level_flags = 3;
+ header |= (level_flags << 6);
+ if (s->strstart != 0) header |= PRESET_DICT;
+ header += 31 - (header % 31);
+
+ s->status = BUSY_STATE;
+ putShortMSB(s, header);
+
+ /* Save the adler32 of the preset dictionary: */
+ if (s->strstart != 0) {
+ putShortMSB(s, (uInt)(strm->adler >> 16));
+ putShortMSB(s, (uInt)(strm->adler & 0xffff));
+ }
+ strm->adler = 1L;
+ }
+
+ /* Flush as much pending output as possible */
+ if (s->pending != 0) {
+ flush_pending(strm);
+ if (strm->avail_out == 0) {
+ /* Since avail_out is 0, deflate will be called again with
+ * more output space, but possibly with both pending and
+ * avail_in equal to zero. There won't be anything to do,
+ * but this is not an error situation so make sure we
+ * return OK instead of BUF_ERROR at next call of deflate:
+ */
+ s->last_flush = -1;
+ return Z_OK;
+ }
+
+ /* Make sure there is something to do and avoid duplicate consecutive
+ * flushes. For repeated and useless calls with Z_FINISH, we keep
+ * returning Z_STREAM_END instead of Z_BUFF_ERROR.
+ */
+ } else if (strm->avail_in == 0 && flush <= old_flush &&
+ flush != Z_FINISH) {
+ return Z_BUF_ERROR;
+ }
+
+ /* User must not provide more input after the first FINISH: */
+ if (s->status == FINISH_STATE && strm->avail_in != 0) {
+ return Z_BUF_ERROR;
+ }
+
+ /* Start a new block or continue the current one.
+ */
+ if (strm->avail_in != 0 || s->lookahead != 0 ||
+ (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
+ block_state bstate;
+
+ bstate = (*(configuration_table[s->level].func))(s, flush);
+
+ if (bstate == finish_started || bstate == finish_done) {
+ s->status = FINISH_STATE;
+ }
+ if (bstate == need_more || bstate == finish_started) {
+ if (strm->avail_out == 0) {
+ s->last_flush = -1; /* avoid BUF_ERROR next call, see above */
+ }
+ return Z_OK;
+ /* If flush != Z_NO_FLUSH && avail_out == 0, the next call
+ * of deflate should use the same flush parameter to make sure
+ * that the flush is complete. So we don't have to output an
+ * empty block here, this will be done at next call. This also
+ * ensures that for a very small output buffer, we emit at most
+ * one empty block.
+ */
+ }
+ if (bstate == block_done) {
+ if (flush == Z_PARTIAL_FLUSH) {
+ zlib_tr_align(s);
+ } else if (flush == Z_PACKET_FLUSH) {
+ /* Output just the 3-bit `stored' block type value,
+ but not a zero length. */
+ zlib_tr_stored_type_only(s);
+ } else { /* FULL_FLUSH or SYNC_FLUSH */
+ zlib_tr_stored_block(s, (char*)0, 0L, 0);
+ /* For a full flush, this empty block will be recognized
+ * as a special marker by inflate_sync().
+ */
+ if (flush == Z_FULL_FLUSH) {
+ CLEAR_HASH(s); /* forget history */
+ }
+ }
+ flush_pending(strm);
+ if (strm->avail_out == 0) {
+ s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */
+ return Z_OK;
+ }
+ }
+ }
+ Assert(strm->avail_out > 0, "bug2");
+
+ if (flush != Z_FINISH) return Z_OK;
+ if (s->noheader) return Z_STREAM_END;
+
+ /* Write the zlib trailer (adler32) */
+ putShortMSB(s, (uInt)(strm->adler >> 16));
+ putShortMSB(s, (uInt)(strm->adler & 0xffff));
+ flush_pending(strm);
+ /* If avail_out is zero, the application will call deflate again
+ * to flush the rest.
+ */
+ s->noheader = -1; /* write the trailer only once! */
+ return s->pending != 0 ? Z_OK : Z_STREAM_END;
+}
+
+/* ========================================================================= */
+int zlib_deflateEnd(
+ z_streamp strm
+)
+{
+ int status;
+ deflate_state *s;
+
+ if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
+ s = (deflate_state *) strm->state;
+
+ status = s->status;
+ if (status != INIT_STATE && status != BUSY_STATE &&
+ status != FINISH_STATE) {
+ return Z_STREAM_ERROR;
+ }
+
+ strm->state = NULL;
+
+ return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
+}
+
+/* =========================================================================
+ * Copy the source state to the destination state.
+ */
+int zlib_deflateCopy (
+ z_streamp dest,
+ z_streamp source
+)
+{
+#ifdef MAXSEG_64K
+ return Z_STREAM_ERROR;
+#else
+ deflate_state *ds;
+ deflate_state *ss;
+ ush *overlay;
+ deflate_workspace *mem;
+
+
+ if (source == NULL || dest == NULL || source->state == NULL) {
+ return Z_STREAM_ERROR;
+ }
+
+ ss = (deflate_state *) source->state;
+
+ *dest = *source;
+
+ mem = (deflate_workspace *) dest->workspace;
+
+ ds = &(mem->deflate_memory);
+
+ dest->state = (struct internal_state *) ds;
+ *ds = *ss;
+ ds->strm = dest;
+
+ ds->window = (Byte *) mem->window_memory;
+ ds->prev = (Pos *) mem->prev_memory;
+ ds->head = (Pos *) mem->head_memory;
+ overlay = (ush *) mem->overlay_memory;
+ ds->pending_buf = (uch *) overlay;
+
+ memcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
+ memcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));
+ memcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));
+ memcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
+
+ ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
+ ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);
+ ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;
+
+ ds->l_desc.dyn_tree = ds->dyn_ltree;
+ ds->d_desc.dyn_tree = ds->dyn_dtree;
+ ds->bl_desc.dyn_tree = ds->bl_tree;
+
+ return Z_OK;
+#endif
+}
+
+/* ===========================================================================
+ * Read a new buffer from the current input stream, update the adler32
+ * and total number of bytes read. All deflate() input goes through
+ * this function so some applications may wish to modify it to avoid
+ * allocating a large strm->next_in buffer and copying from it.
+ * (See also flush_pending()).
+ */
+static int read_buf(
+ z_streamp strm,
+ Byte *buf,
+ unsigned size
+)
+{
+ unsigned len = strm->avail_in;
+
+ if (len > size) len = size;
+ if (len == 0) return 0;
+
+ strm->avail_in -= len;
+
+ if (!((deflate_state *)(strm->state))->noheader) {
+ strm->adler = zlib_adler32(strm->adler, strm->next_in, len);
+ }
+ memcpy(buf, strm->next_in, len);
+ strm->next_in += len;
+ strm->total_in += len;
+
+ return (int)len;
+}
+
+/* ===========================================================================
+ * Initialize the "longest match" routines for a new zlib stream
+ */
+static void lm_init(
+ deflate_state *s
+)
+{
+ s->window_size = (ulg)2L*s->w_size;
+
+ CLEAR_HASH(s);
+
+ /* Set the default configuration parameters:
+ */
+ s->max_lazy_match = configuration_table[s->level].max_lazy;
+ s->good_match = configuration_table[s->level].good_length;
+ s->nice_match = configuration_table[s->level].nice_length;
+ s->max_chain_length = configuration_table[s->level].max_chain;
+
+ s->strstart = 0;
+ s->block_start = 0L;
+ s->lookahead = 0;
+ s->match_length = s->prev_length = MIN_MATCH-1;
+ s->match_available = 0;
+ s->ins_h = 0;
+}
+
+/* ===========================================================================
+ * 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
+ * OUT assertion: the match length is not greater than s->lookahead.
+ */
+/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
+ * match.S. The code will be functionally equivalent.
+ */
+static uInt longest_match(
+ deflate_state *s,
+ IPos cur_match /* current match */
+)
+{
+ unsigned chain_length = s->max_chain_length;/* max hash chain length */
+ register Byte *scan = s->window + s->strstart; /* current string */
+ register Byte *match; /* matched string */
+ register int len; /* length of current match */
+ int best_len = s->prev_length; /* best match length so far */
+ int nice_match = s->nice_match; /* stop if match long enough */
+ IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
+ s->strstart - (IPos)MAX_DIST(s) : NIL;
+ /* Stop when cur_match becomes <= limit. To simplify the code,
+ * we prevent matches with the string of window index 0.
+ */
+ Pos *prev = s->prev;
+ uInt wmask = s->w_mask;
+
+#ifdef UNALIGNED_OK
+ /* Compare two bytes at a time. Note: this is not always beneficial.
+ * Try with and without -DUNALIGNED_OK to check.
+ */
+ register Byte *strend = s->window + s->strstart + MAX_MATCH - 1;
+ register ush scan_start = *(ush*)scan;
+ register ush scan_end = *(ush*)(scan+best_len-1);
+#else
+ register Byte *strend = s->window + s->strstart + MAX_MATCH;
+ register Byte scan_end1 = scan[best_len-1];
+ register Byte scan_end = scan[best_len];
+#endif
+
+ /* 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.
+ */
+ Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
+
+ /* Do not waste too much time if we already have a good match: */
+ if (s->prev_length >= s->good_match) {
+ chain_length >>= 2;
+ }
+ /* Do not look for matches beyond the end of the input. This is necessary
+ * to make deflate deterministic.
+ */
+ if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
+
+ Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
+
+ do {
+ Assert(cur_match < s->strstart, "no future");
+ match = s->window + cur_match;
+
+ /* Skip to next match if the match length cannot increase
+ * or if the match length is less than 2:
+ */
+#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)
+ /* This code assumes sizeof(unsigned short) == 2. Do not use
+ * UNALIGNED_OK if your compiler uses a different size.
+ */
+ if (*(ush*)(match+best_len-1) != scan_end ||
+ *(ush*)match != scan_start) continue;
+
+ /* 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. Compare 2 bytes at a time at
+ * strstart+3, +5, ... up to strstart+257. We check for insufficient
+ * lookahead only every 4th comparison; the 128th check will be made
+ * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is
+ * necessary to put more guard bytes at the end of the window, or
+ * to check more often for insufficient lookahead.
+ */
+ Assert(scan[2] == match[2], "scan[2]?");
+ scan++, match++;
+ do {
+ } while (*(ush*)(scan+=2) == *(ush*)(match+=2) &&
+ *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+ *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+ *(ush*)(scan+=2) == *(ush*)(match+=2) &&
+ scan < strend);
+ /* The funny "do {}" generates better code on most compilers */
+
+ /* Here, scan <= window+strstart+257 */
+ Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+ if (*scan == *match) scan++;
+
+ len = (MAX_MATCH - 1) - (int)(strend-scan);
+ scan = strend - (MAX_MATCH-1);
+
+#else /* UNALIGNED_OK */
+
+ 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++;
+ Assert(*scan == *match, "match[2]?");
+
+ /* 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);
+
+ Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+
+ len = MAX_MATCH - (int)(strend - scan);
+ scan = strend - MAX_MATCH;
+
+#endif /* UNALIGNED_OK */
+
+ if (len > best_len) {
+ s->match_start = cur_match;
+ best_len = len;
+ if (len >= nice_match) break;
+#ifdef UNALIGNED_OK
+ scan_end = *(ush*)(scan+best_len-1);
+#else
+ scan_end1 = scan[best_len-1];
+ scan_end = scan[best_len];
+#endif
+ }
+ } while ((cur_match = prev[cur_match & wmask]) > limit
+ && --chain_length != 0);
+
+ if ((uInt)best_len <= s->lookahead) return best_len;
+ return s->lookahead;
+}
+
+#ifdef DEBUG_ZLIB
+/* ===========================================================================
+ * Check that the match at match_start is indeed a match.
+ */
+static void check_match(
+ deflate_state *s,
+ IPos start,
+ IPos match,
+ int length
+)
+{
+ /* check that the match is indeed a match */
+ if (memcmp((char *)s->window + match,
+ (char *)s->window + start, length) != EQUAL) {
+ fprintf(stderr, " start %u, match %u, length %d\n",
+ start, match, length);
+ do {
+ fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
+ } while (--length != 0);
+ z_error("invalid match");
+ }
+ if (z_verbose > 1) {
+ fprintf(stderr,"\\[%d,%d]", start-match, length);
+ do { putc(s->window[start++], stderr); } while (--length != 0);
+ }
+}
+#else
+# define check_match(s, start, match, length)
+#endif
+
+/* ===========================================================================
+ * Fill the window when the lookahead becomes insufficient.
+ * Updates strstart and lookahead.
+ *
+ * IN assertion: lookahead < MIN_LOOKAHEAD
+ * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
+ * At least one byte has been read, or avail_in == 0; reads are
+ * performed for at least two bytes (required for the zip translate_eol
+ * option -- not supported here).
+ */
+static void fill_window(
+ deflate_state *s
+)
+{
+ register unsigned n, m;
+ register Pos *p;
+ unsigned more; /* Amount of free space at the end of the window. */
+ uInt wsize = s->w_size;
+
+ do {
+ more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
+
+ /* Deal with !@#$% 64K limit: */
+ if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
+ more = wsize;
+
+ } else 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--;
+
+ /* 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.
+ */
+ } else if (s->strstart >= wsize+MAX_DIST(s)) {
+
+ memcpy((char *)s->window, (char *)s->window+wsize,
+ (unsigned)wsize);
+ s->match_start -= wsize;
+ s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
+ s->block_start -= (long) wsize;
+
+ /* Slide the hash table (could be avoided with 32 bit values
+ at the expense of memory usage). We slide even when level == 0
+ to keep the hash table consistent if we switch back to level > 0
+ later. (Using level 0 permanently is not an optimal usage of
+ zlib, so we don't care about this pathological case.)
+ */
+ n = s->hash_size;
+ p = &s->head[n];
+ do {
+ m = *--p;
+ *p = (Pos)(m >= wsize ? m-wsize : NIL);
+ } while (--n);
+
+ n = wsize;
+ p = &s->prev[n];
+ do {
+ m = *--p;
+ *p = (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.
+ */
+ } while (--n);
+ more += wsize;
+ }
+ if (s->strm->avail_in == 0) return;
+
+ /* If there was no sliding:
+ * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
+ * more == window_size - lookahead - strstart
+ * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
+ * => more >= window_size - 2*WSIZE + 2
+ * In the BIG_MEM or MMAP case (not yet supported),
+ * window_size == input_size + MIN_LOOKAHEAD &&
+ * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
+ * Otherwise, window_size == 2*WSIZE so more >= 2.
+ * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
+ */
+ Assert(more >= 2, "more < 2");
+
+ n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
+ s->lookahead += n;
+
+ /* Initialize the hash value now that we have some input: */
+ if (s->lookahead >= MIN_MATCH) {
+ s->ins_h = s->window[s->strstart];
+ UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
+#if MIN_MATCH != 3
+ Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+ }
+ /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
+ * but this is not important since only literal bytes will be emitted.
+ */
+
+ } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
+}
+
+/* ===========================================================================
+ * 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_ONLY(s, eof) { \
+ zlib_tr_flush_block(s, (s->block_start >= 0L ? \
+ (char *)&s->window[(unsigned)s->block_start] : \
+ NULL), \
+ (ulg)((long)s->strstart - s->block_start), \
+ (eof)); \
+ s->block_start = s->strstart; \
+ flush_pending(s->strm); \
+ Tracev((stderr,"[FLUSH]")); \
+}
+
+/* Same but force premature exit if necessary. */
+#define FLUSH_BLOCK(s, eof) { \
+ FLUSH_BLOCK_ONLY(s, eof); \
+ if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
+}
+
+/* ===========================================================================
+ * Copy without compression as much as possible from the input stream, return
+ * the current block state.
+ * This function does not insert new strings in the dictionary since
+ * uncompressible data is probably not useful. This function is used
+ * only for the level=0 compression option.
+ * NOTE: this function should be optimized to avoid extra copying from
+ * window to pending_buf.
+ */
+static block_state deflate_stored(
+ deflate_state *s,
+ int flush
+)
+{
+ /* Stored blocks are limited to 0xffff bytes, pending_buf is limited
+ * to pending_buf_size, and each stored block has a 5 byte header:
+ */
+ ulg max_block_size = 0xffff;
+ ulg max_start;
+
+ if (max_block_size > s->pending_buf_size - 5) {
+ max_block_size = s->pending_buf_size - 5;
+ }
+
+ /* Copy as much as possible from input to output: */
+ for (;;) {
+ /* Fill the window as much as possible: */
+ if (s->lookahead <= 1) {
+
+ Assert(s->strstart < s->w_size+MAX_DIST(s) ||
+ s->block_start >= (long)s->w_size, "slide too late");
+
+ fill_window(s);
+ if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;
+
+ if (s->lookahead == 0) break; /* flush the current block */
+ }
+ Assert(s->block_start >= 0L, "block gone");
+
+ s->strstart += s->lookahead;
+ s->lookahead = 0;
+
+ /* Emit a stored block if pending_buf will be full: */
+ max_start = s->block_start + max_block_size;
+ if (s->strstart == 0 || (ulg)s->strstart >= max_start) {
+ /* strstart == 0 is possible when wraparound on 16-bit machine */
+ s->lookahead = (uInt)(s->strstart - max_start);
+ s->strstart = (uInt)max_start;
+ FLUSH_BLOCK(s, 0);
+ }
+ /* Flush if we may have to slide, otherwise block_start may become
+ * negative and the data will be gone:
+ */
+ if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {
+ FLUSH_BLOCK(s, 0);
+ }
+ }
+ FLUSH_BLOCK(s, flush == Z_FINISH);
+ return flush == Z_FINISH ? finish_done : block_done;
+}
+
+/* ===========================================================================
+ * Compress as much as possible from the input stream, return the current
+ * block state.
+ * This function does not perform lazy evaluation of matches and inserts
+ * new strings in the dictionary only for unmatched strings or for short
+ * matches. It is used only for the fast compression options.
+ */
+static block_state deflate_fast(
+ deflate_state *s,
+ int flush
+)
+{
+ IPos hash_head = NIL; /* head of the hash chain */
+ int bflush; /* set if current block must be flushed */
+
+ for (;;) {
+ /* 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.
+ */
+ if (s->lookahead < MIN_LOOKAHEAD) {
+ fill_window(s);
+ if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
+ return need_more;
+ }
+ if (s->lookahead == 0) break; /* flush the current block */
+ }
+
+ /* Insert the string window[strstart .. strstart+2] in the
+ * dictionary, and set hash_head to the head of the hash chain:
+ */
+ if (s->lookahead >= MIN_MATCH) {
+ INSERT_STRING(s, s->strstart, hash_head);
+ }
+
+ /* Find the longest match, discarding those <= prev_length.
+ * At this point we have always match_length < MIN_MATCH
+ */
+ if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {
+ /* 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).
+ */
+ if (s->strategy != Z_HUFFMAN_ONLY) {
+ s->match_length = longest_match (s, hash_head);
+ }
+ /* longest_match() sets match_start */
+ }
+ if (s->match_length >= MIN_MATCH) {
+ check_match(s, s->strstart, s->match_start, s->match_length);
+
+ bflush = zlib_tr_tally(s, s->strstart - s->match_start,
+ s->match_length - MIN_MATCH);
+
+ s->lookahead -= s->match_length;
+
+ /* Insert new strings in the hash table only if the match length
+ * is not too large. This saves time but degrades compression.
+ */
+ if (s->match_length <= s->max_insert_length &&
+ s->lookahead >= MIN_MATCH) {
+ s->match_length--; /* string at strstart already in hash table */
+ do {
+ s->strstart++;
+ INSERT_STRING(s, s->strstart, hash_head);
+ /* strstart never exceeds WSIZE-MAX_MATCH, so there are
+ * always MIN_MATCH bytes ahead.
+ */
+ } while (--s->match_length != 0);
+ s->strstart++;
+ } else {
+ s->strstart += s->match_length;
+ s->match_length = 0;
+ s->ins_h = s->window[s->strstart];
+ UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);
+#if MIN_MATCH != 3
+ Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+ /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
+ * matter since it will be recomputed at next deflate call.
+ */
+ }
+ } else {
+ /* No match, output a literal byte */
+ Tracevv((stderr,"%c", s->window[s->strstart]));
+ bflush = zlib_tr_tally (s, 0, s->window[s->strstart]);
+ s->lookahead--;
+ s->strstart++;
+ }
+ if (bflush) FLUSH_BLOCK(s, 0);
+ }
+ FLUSH_BLOCK(s, flush == Z_FINISH);
+ return flush == Z_FINISH ? finish_done : block_done;
+}
+
+/* ===========================================================================
+ * 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.
+ */
+static block_state deflate_slow(
+ deflate_state *s,
+ int flush
+)
+{
+ IPos hash_head = NIL; /* head of hash chain */
+ int bflush; /* set if current block must be flushed */
+
+ /* Process the input block. */
+ for (;;) {
+ /* 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.
+ */
+ if (s->lookahead < MIN_LOOKAHEAD) {
+ fill_window(s);
+ if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
+ return need_more;
+ }
+ if (s->lookahead == 0) break; /* flush the current block */
+ }
+
+ /* Insert the string window[strstart .. strstart+2] in the
+ * dictionary, and set hash_head to the head of the hash chain:
+ */
+ if (s->lookahead >= MIN_MATCH) {
+ INSERT_STRING(s, s->strstart, hash_head);
+ }
+
+ /* Find the longest match, discarding those <= prev_length.
+ */
+ s->prev_length = s->match_length, s->prev_match = s->match_start;
+ s->match_length = MIN_MATCH-1;
+
+ if (hash_head != NIL && s->prev_length < s->max_lazy_match &&
+ s->strstart - hash_head <= MAX_DIST(s)) {
+ /* 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).
+ */
+ if (s->strategy != Z_HUFFMAN_ONLY) {
+ s->match_length = longest_match (s, hash_head);
+ }
+ /* longest_match() sets match_start */
+
+ if (s->match_length <= 5 && (s->strategy == Z_FILTERED ||
+ (s->match_length == MIN_MATCH &&
+ s->strstart - s->match_start > TOO_FAR))) {
+
+ /* If prev_match is also MIN_MATCH, match_start is garbage
+ * but we will ignore the current match anyway.
+ */
+ s->match_length = MIN_MATCH-1;
+ }
+ }
+ /* If there was a match at the previous step and the current
+ * match is not better, output the previous match:
+ */
+ if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
+ uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
+ /* Do not insert strings in hash table beyond this. */
+
+ check_match(s, s->strstart-1, s->prev_match, s->prev_length);
+
+ bflush = zlib_tr_tally(s, s->strstart -1 - s->prev_match,
+ s->prev_length - MIN_MATCH);
+
+ /* Insert in hash table all strings up to the end of the match.
+ * strstart-1 and strstart are already inserted. If there is not
+ * enough lookahead, the last two strings are not inserted in
+ * the hash table.
+ */
+ s->lookahead -= s->prev_length-1;
+ s->prev_length -= 2;
+ do {
+ if (++s->strstart <= max_insert) {
+ INSERT_STRING(s, s->strstart, hash_head);
+ }
+ } while (--s->prev_length != 0);
+ s->match_available = 0;
+ s->match_length = MIN_MATCH-1;
+ s->strstart++;
+
+ if (bflush) FLUSH_BLOCK(s, 0);
+
+ } else if (s->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", s->window[s->strstart-1]));
+ if (zlib_tr_tally (s, 0, s->window[s->strstart-1])) {
+ FLUSH_BLOCK_ONLY(s, 0);
+ }
+ s->strstart++;
+ s->lookahead--;
+ if (s->strm->avail_out == 0) return need_more;
+ } else {
+ /* There is no previous match to compare with, wait for
+ * the next step to decide.
+ */
+ s->match_available = 1;
+ s->strstart++;
+ s->lookahead--;
+ }
+ }
+ Assert (flush != Z_NO_FLUSH, "no flush?");
+ if (s->match_available) {
+ Tracevv((stderr,"%c", s->window[s->strstart-1]));
+ zlib_tr_tally (s, 0, s->window[s->strstart-1]);
+ s->match_available = 0;
+ }
+ FLUSH_BLOCK(s, flush == Z_FINISH);
+ return flush == Z_FINISH ? finish_done : block_done;
+}
+
+int zlib_deflate_workspacesize(void)
+{
+ return sizeof(deflate_workspace);
+}
diff --git a/lib/zlib_deflate/deflate_syms.c b/lib/zlib_deflate/deflate_syms.c
new file mode 100644
index 0000000..5985b28
--- /dev/null
+++ b/lib/zlib_deflate/deflate_syms.c
@@ -0,0 +1,21 @@
+/*
+ * linux/lib/zlib_deflate/deflate_syms.c
+ *
+ * Exported symbols for the deflate functionality.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/zlib.h>
+
+EXPORT_SYMBOL(zlib_deflate_workspacesize);
+EXPORT_SYMBOL(zlib_deflate);
+EXPORT_SYMBOL(zlib_deflateInit_);
+EXPORT_SYMBOL(zlib_deflateInit2_);
+EXPORT_SYMBOL(zlib_deflateEnd);
+EXPORT_SYMBOL(zlib_deflateReset);
+EXPORT_SYMBOL(zlib_deflateCopy);
+EXPORT_SYMBOL(zlib_deflateParams);
+MODULE_LICENSE("GPL");
diff --git a/lib/zlib_deflate/deftree.c b/lib/zlib_deflate/deftree.c
new file mode 100644
index 0000000..ddf3482
--- /dev/null
+++ b/lib/zlib_deflate/deftree.c
@@ -0,0 +1,1113 @@
+/* +++ trees.c */
+/* trees.c -- output deflated data using Huffman coding
+ * Copyright (C) 1995-1996 Jean-loup Gailly
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * ALGORITHM
+ *
+ * The "deflation" process uses several Huffman trees. The more
+ * common source values are represented by shorter bit sequences.
+ *
+ * Each code tree is stored 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 inflate process, as described
+ * in the deflate specification.
+ *
+ * REFERENCES
+ *
+ * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification".
+ * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc
+ *
+ * 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.
+ */
+
+/* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */
+
+/* #include "deflate.h" */
+
+#include <linux/zutil.h>
+#include "defutil.h"
+
+#ifdef DEBUG_ZLIB
+# include <ctype.h>
+#endif
+
+/* ===========================================================================
+ * Constants
+ */
+
+#define MAX_BL_BITS 7
+/* Bit length codes must not exceed MAX_BL_BITS bits */
+
+#define END_BLOCK 256
+/* end of block literal code */
+
+#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) */
+
+static const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */
+ = {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};
+
+static const int extra_dbits[D_CODES] /* extra bits for each distance code */
+ = {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};
+
+static const int extra_blbits[BL_CODES]/* extra bits for each bit length code */
+ = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
+
+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};
+/* The lengths of the bit length codes are sent in order of decreasing
+ * probability, to avoid transmitting the lengths for unused bit length codes.
+ */
+
+#define Buf_size (8 * 2*sizeof(char))
+/* Number of bits used within bi_buf. (bi_buf might be implemented on
+ * more than 16 bits on some systems.)
+ */
+
+/* ===========================================================================
+ * Local data. These are initialized only once.
+ */
+
+static 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 zlib_tr_init
+ * below).
+ */
+
+static ct_data static_dtree[D_CODES];
+/* The static distance tree. (Actually a trivial tree since all codes use
+ * 5 bits.)
+ */
+
+static 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 uch length_code[MAX_MATCH-MIN_MATCH+1];
+/* length code for each normalized match length (0 == MIN_MATCH) */
+
+static int base_length[LENGTH_CODES];
+/* First normalized length for each code (0 = MIN_MATCH) */
+
+static int base_dist[D_CODES];
+/* First normalized distance for each code (0 = distance of 1) */
+
+struct static_tree_desc_s {
+ const ct_data *static_tree; /* static tree or NULL */
+ const int *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 */
+};
+
+static static_tree_desc static_l_desc =
+{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS};
+
+static static_tree_desc static_d_desc =
+{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS};
+
+static static_tree_desc static_bl_desc =
+{(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS};
+
+/* ===========================================================================
+ * Local (static) routines in this file.
+ */
+
+static void tr_static_init (void);
+static void init_block (deflate_state *s);
+static void pqdownheap (deflate_state *s, ct_data *tree, int k);
+static void gen_bitlen (deflate_state *s, tree_desc *desc);
+static void gen_codes (ct_data *tree, int max_code, ush *bl_count);
+static void build_tree (deflate_state *s, tree_desc *desc);
+static void scan_tree (deflate_state *s, ct_data *tree, int max_code);
+static void send_tree (deflate_state *s, ct_data *tree, int max_code);
+static int build_bl_tree (deflate_state *s);
+static void send_all_trees (deflate_state *s, int lcodes, int dcodes,
+ int blcodes);
+static void compress_block (deflate_state *s, ct_data *ltree,
+ ct_data *dtree);
+static void set_data_type (deflate_state *s);
+static unsigned bi_reverse (unsigned value, int length);
+static void bi_windup (deflate_state *s);
+static void bi_flush (deflate_state *s);
+static void copy_block (deflate_state *s, char *buf, unsigned len,
+ int header);
+
+#ifndef DEBUG_ZLIB
+# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
+ /* Send a code of the given tree. c and tree must not have side effects */
+
+#else /* DEBUG_ZLIB */
+# define send_code(s, c, tree) \
+ { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \
+ send_bits(s, tree[c].Code, tree[c].Len); }
+#endif
+
+#define d_code(dist) \
+ ((dist) < 256 ? dist_code[dist] : 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.
+ */
+
+/* ===========================================================================
+ * Send a value on a given number of bits.
+ * IN assertion: length <= 16 and value fits in length bits.
+ */
+#ifdef DEBUG_ZLIB
+static void send_bits (deflate_state *s, int value, int length);
+
+static void send_bits(
+ deflate_state *s,
+ int value, /* value to send */
+ int length /* number of bits */
+)
+{
+ Tracevv((stderr," l %2d v %4x ", length, value));
+ Assert(length > 0 && length <= 15, "invalid length");
+ s->bits_sent += (ulg)length;
+
+ /* 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 (s->bi_valid > (int)Buf_size - length) {
+ s->bi_buf |= (value << s->bi_valid);
+ put_short(s, s->bi_buf);
+ s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
+ s->bi_valid += length - Buf_size;
+ } else {
+ s->bi_buf |= value << s->bi_valid;
+ s->bi_valid += length;
+ }
+}
+#else /* !DEBUG_ZLIB */
+
+#define send_bits(s, value, length) \
+{ int len = length;\
+ if (s->bi_valid > (int)Buf_size - len) {\
+ int val = value;\
+ s->bi_buf |= (val << s->bi_valid);\
+ put_short(s, s->bi_buf);\
+ s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
+ s->bi_valid += len - Buf_size;\
+ } else {\
+ s->bi_buf |= (value) << s->bi_valid;\
+ s->bi_valid += len;\
+ }\
+}
+#endif /* DEBUG_ZLIB */
+
+/* ===========================================================================
+ * Initialize the various 'constant' tables. In a multi-threaded environment,
+ * this function may be called by two threads concurrently, but this is
+ * harmless since both invocations do exactly the same thing.
+ */
+static void tr_static_init(void)
+{
+ static int static_init_done;
+ int n; /* iterates over tree elements */
+ int bits; /* bit counter */
+ int length; /* length value */
+ int code; /* code value */
+ int dist; /* distance index */
+ ush bl_count[MAX_BITS+1];
+ /* number of codes at each bit length for an optimal tree */
+
+ if (static_init_done) return;
+
+ /* 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, "tr_static_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, "tr_static_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, "tr_static_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, bl_count);
+
+ /* The static distance tree is trivial: */
+ for (n = 0; n < D_CODES; n++) {
+ static_dtree[n].Len = 5;
+ static_dtree[n].Code = bi_reverse((unsigned)n, 5);
+ }
+ static_init_done = 1;
+}
+
+/* ===========================================================================
+ * Initialize the tree data structures for a new zlib stream.
+ */
+void zlib_tr_init(
+ deflate_state *s
+)
+{
+ tr_static_init();
+
+ s->compressed_len = 0L;
+
+ s->l_desc.dyn_tree = s->dyn_ltree;
+ s->l_desc.stat_desc = &static_l_desc;
+
+ s->d_desc.dyn_tree = s->dyn_dtree;
+ s->d_desc.stat_desc = &static_d_desc;
+
+ s->bl_desc.dyn_tree = s->bl_tree;
+ s->bl_desc.stat_desc = &static_bl_desc;
+
+ s->bi_buf = 0;
+ s->bi_valid = 0;
+ s->last_eob_len = 8; /* enough lookahead for inflate */
+#ifdef DEBUG_ZLIB
+ s->bits_sent = 0L;
+#endif
+
+ /* Initialize the first block of the first file: */
+ init_block(s);
+}
+
+/* ===========================================================================
+ * Initialize a new block.
+ */
+static void init_block(
+ deflate_state *s
+)
+{
+ int n; /* iterates over tree elements */
+
+ /* Initialize the trees. */
+ for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0;
+ for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0;
+ for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0;
+
+ s->dyn_ltree[END_BLOCK].Freq = 1;
+ s->opt_len = s->static_len = 0L;
+ s->last_lit = s->matches = 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(s, tree, top) \
+{\
+ top = s->heap[SMALLEST]; \
+ s->heap[SMALLEST] = s->heap[s->heap_len--]; \
+ pqdownheap(s, tree, SMALLEST); \
+}
+
+/* ===========================================================================
+ * 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, depth) \
+ (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,
+ * 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).
+ */
+static void pqdownheap(
+ deflate_state *s,
+ ct_data *tree, /* the tree to restore */
+ int k /* node to move down */
+)
+{
+ int v = s->heap[k];
+ int j = k << 1; /* left son of k */
+ while (j <= s->heap_len) {
+ /* Set j to the smallest of the two sons: */
+ if (j < s->heap_len &&
+ smaller(tree, s->heap[j+1], s->heap[j], s->depth)) {
+ j++;
+ }
+ /* Exit if v is smaller than both sons */
+ if (smaller(tree, v, s->heap[j], s->depth)) break;
+
+ /* Exchange v with the smallest son */
+ s->heap[k] = s->heap[j]; k = j;
+
+ /* And continue down the tree, setting j to the left son of k */
+ j <<= 1;
+ }
+ s->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(
+ deflate_state *s,
+ tree_desc *desc /* the tree descriptor */
+)
+{
+ ct_data *tree = desc->dyn_tree;
+ int max_code = desc->max_code;
+ const ct_data *stree = desc->stat_desc->static_tree;
+ const int *extra = desc->stat_desc->extra_bits;
+ int base = desc->stat_desc->extra_base;
+ int max_length = desc->stat_desc->max_length;
+ 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++) s->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[s->heap[s->heap_max]].Len = 0; /* root of the heap */
+
+ for (h = s->heap_max+1; h < HEAP_SIZE; h++) {
+ n = s->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 */
+
+ s->bl_count[bits]++;
+ xbits = 0;
+ if (n >= base) xbits = extra[n-base];
+ f = tree[n].Freq;
+ s->opt_len += (ulg)f * (bits + xbits);
+ if (stree) s->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 (s->bl_count[bits] == 0) bits--;
+ s->bl_count[bits]--; /* move one leaf down the tree */
+ s->bl_count[bits+1] += 2; /* move one overflow item as its brother */
+ s->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 = s->bl_count[bits];
+ while (n != 0) {
+ m = s->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));
+ s->opt_len += ((long)bits - (long)tree[m].Len)
+ *(long)tree[m].Freq;
+ tree[m].Len = (ush)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, /* the tree to decorate */
+ int max_code, /* largest code with non zero frequency */
+ ush *bl_count /* number of codes at each bit length */
+)
+{
+ 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 + 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,
+ "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);
+
+ Tracecv(tree != 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.
+ */
+static void build_tree(
+ deflate_state *s,
+ tree_desc *desc /* the tree descriptor */
+)
+{
+ ct_data *tree = desc->dyn_tree;
+ const ct_data *stree = desc->stat_desc->static_tree;
+ int elems = desc->stat_desc->elems;
+ int n, m; /* iterate over heap elements */
+ int max_code = -1; /* largest code with non zero frequency */
+ int node; /* new node being created */
+
+ /* 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.
+ */
+ s->heap_len = 0, s->heap_max = HEAP_SIZE;
+
+ for (n = 0; n < elems; n++) {
+ if (tree[n].Freq != 0) {
+ s->heap[++(s->heap_len)] = max_code = n;
+ s->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 (s->heap_len < 2) {
+ node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0);
+ tree[node].Freq = 1;
+ s->depth[node] = 0;
+ s->opt_len--; if (stree) s->static_len -= stree[node].Len;
+ /* node 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 = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n);
+
+ /* Construct the Huffman tree by repeatedly combining the least two
+ * frequent nodes.
+ */
+ node = elems; /* next internal node of the tree */
+ do {
+ pqremove(s, tree, n); /* n = node of least frequency */
+ m = s->heap[SMALLEST]; /* m = node of next least frequency */
+
+ s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */
+ s->heap[--(s->heap_max)] = m;
+
+ /* Create a new node father of n and m */
+ tree[node].Freq = tree[n].Freq + tree[m].Freq;
+ s->depth[node] = (uch) (max(s->depth[n], s->depth[m]) + 1);
+ tree[n].Dad = tree[m].Dad = (ush)node;
+#ifdef DUMP_BL_TREE
+ if (tree == s->bl_tree) {
+ fprintf(stderr,"\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 */
+ s->heap[SMALLEST] = node++;
+ pqdownheap(s, tree, SMALLEST);
+
+ } while (s->heap_len >= 2);
+
+ s->heap[--(s->heap_max)] = s->heap[SMALLEST];
+
+ /* At this point, the fields freq and dad are set. We can now
+ * generate the bit lengths.
+ */
+ gen_bitlen(s, (tree_desc *)desc);
+
+ /* The field len is now set, we can generate the bit codes */
+ gen_codes ((ct_data *)tree, max_code, s->bl_count);
+}
+
+/* ===========================================================================
+ * Scan a literal or distance tree to determine the frequencies of the codes
+ * in the bit length tree.
+ */
+static void scan_tree(
+ deflate_state *s,
+ ct_data *tree, /* the tree to be scanned */
+ int max_code /* and its largest code of non zero frequency */
+)
+{
+ 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 = (ush)0xffff; /* guard */
+
+ 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) {
+ s->bl_tree[curlen].Freq += count;
+ } else if (curlen != 0) {
+ if (curlen != prevlen) s->bl_tree[curlen].Freq++;
+ s->bl_tree[REP_3_6].Freq++;
+ } else if (count <= 10) {
+ s->bl_tree[REPZ_3_10].Freq++;
+ } else {
+ s->bl_tree[REPZ_11_138].Freq++;
+ }
+ 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;
+ }
+ }
+}
+
+/* ===========================================================================
+ * Send a literal or distance tree in compressed form, using the codes in
+ * bl_tree.
+ */
+static void send_tree(
+ deflate_state *s,
+ ct_data *tree, /* the tree to be scanned */
+ int max_code /* and its largest code of non zero frequency */
+)
+{
+ 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(s, curlen, s->bl_tree); } while (--count != 0);
+
+ } else if (curlen != 0) {
+ if (curlen != prevlen) {
+ send_code(s, curlen, s->bl_tree); count--;
+ }
+ Assert(count >= 3 && count <= 6, " 3_6?");
+ send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2);
+
+ } else if (count <= 10) {
+ send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3);
+
+ } else {
+ send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, 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(
+ deflate_state *s
+)
+{
+ 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(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code);
+ scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code);
+
+ /* Build the bit length tree: */
+ build_tree(s, (tree_desc *)(&(s->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 (s->bl_tree[bl_order[max_blindex]].Len != 0) break;
+ }
+ /* Update opt_len to include the bit length tree and counts */
+ s->opt_len += 3*(max_blindex+1) + 5+5+4;
+ Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
+ s->opt_len, s->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(
+ deflate_state *s,
+ int lcodes, /* number of codes for each tree */
+ int dcodes, /* number of codes for each tree */
+ int blcodes /* number of codes for each tree */
+)
+{
+ 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(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */
+ send_bits(s, dcodes-1, 5);
+ send_bits(s, 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(s, s->bl_tree[bl_order[rank]].Len, 3);
+ }
+ Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent));
+
+ send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */
+ Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent));
+
+ send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */
+ Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent));
+}
+
+/* ===========================================================================
+ * Send a stored block
+ */
+void zlib_tr_stored_block(
+ deflate_state *s,
+ char *buf, /* input block */
+ ulg stored_len, /* length of input block */
+ int eof /* true if this is the last block for a file */
+)
+{
+ send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
+ s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
+ s->compressed_len += (stored_len + 4) << 3;
+
+ copy_block(s, buf, (unsigned)stored_len, 1); /* with header */
+}
+
+/* Send just the `stored block' type code without any length bytes or data.
+ */
+void zlib_tr_stored_type_only(
+ deflate_state *s
+)
+{
+ send_bits(s, (STORED_BLOCK << 1), 3);
+ bi_windup(s);
+ s->compressed_len = (s->compressed_len + 3) & ~7L;
+}
+
+
+/* ===========================================================================
+ * Send one empty static block to give enough lookahead for inflate.
+ * This takes 10 bits, of which 7 may remain in the bit buffer.
+ * The current inflate code requires 9 bits of lookahead. If the
+ * last two codes for the previous block (real code plus EOB) were coded
+ * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
+ * the last real code. In this case we send two empty static blocks instead
+ * of one. (There are no problems if the previous block is stored or fixed.)
+ * To simplify the code, we assume the worst case of last real code encoded
+ * on one bit only.
+ */
+void zlib_tr_align(
+ deflate_state *s
+)
+{
+ send_bits(s, STATIC_TREES<<1, 3);
+ send_code(s, END_BLOCK, static_ltree);
+ s->compressed_len += 10L; /* 3 for block type, 7 for EOB */
+ bi_flush(s);
+ /* Of the 10 bits for the empty block, we have already sent
+ * (10 - bi_valid) bits. The lookahead for the last real code (before
+ * the EOB of the previous block) was thus at least one plus the length
+ * of the EOB plus what we have just sent of the empty static block.
+ */
+ if (1 + s->last_eob_len + 10 - s->bi_valid < 9) {
+ send_bits(s, STATIC_TREES<<1, 3);
+ send_code(s, END_BLOCK, static_ltree);
+ s->compressed_len += 10L;
+ bi_flush(s);
+ }
+ s->last_eob_len = 7;
+}
+
+/* ===========================================================================
+ * 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.
+ */
+ulg zlib_tr_flush_block(
+ deflate_state *s,
+ char *buf, /* input block, or NULL if too old */
+ ulg stored_len, /* length of input block */
+ int eof /* true if this is the last block for a file */
+)
+{
+ ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
+ int max_blindex = 0; /* index of last bit length code of non zero freq */
+
+ /* Build the Huffman trees unless a stored block is forced */
+ if (s->level > 0) {
+
+ /* Check if the file is ascii or binary */
+ if (s->data_type == Z_UNKNOWN) set_data_type(s);
+
+ /* Construct the literal and distance trees */
+ build_tree(s, (tree_desc *)(&(s->l_desc)));
+ Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len,
+ s->static_len));
+
+ build_tree(s, (tree_desc *)(&(s->d_desc)));
+ Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len,
+ s->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(s);
+
+ /* Determine the best encoding. Compute first the block length in bytes*/
+ opt_lenb = (s->opt_len+3+7)>>3;
+ static_lenb = (s->static_len+3+7)>>3;
+
+ Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ",
+ opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len,
+ s->last_lit));
+
+ if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+
+ } else {
+ Assert(buf != (char*)0, "lost buf");
+ opt_lenb = static_lenb = stored_len + 5; /* force a stored block */
+ }
+
+ /* 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:
+ */
+#ifdef STORED_FILE_OK
+# ifdef FORCE_STORED_FILE
+ if (eof && s->compressed_len == 0L) { /* force stored file */
+# else
+ if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) {
+# endif
+ /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
+ if (buf == (char*)0) error ("block vanished");
+
+ copy_block(s, buf, (unsigned)stored_len, 0); /* without header */
+ s->compressed_len = stored_len << 3;
+ s->method = STORED;
+ } else
+#endif /* STORED_FILE_OK */
+
+#ifdef FORCE_STORED
+ if (buf != (char*)0) { /* force stored block */
+#else
+ if (stored_len+4 <= opt_lenb && buf != (char*)0) {
+ /* 4: two words for the lengths */
+#endif
+ /* 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.
+ */
+ zlib_tr_stored_block(s, buf, stored_len, eof);
+
+#ifdef FORCE_STATIC
+ } else if (static_lenb >= 0) { /* force static trees */
+#else
+ } else if (static_lenb == opt_lenb) {
+#endif
+ send_bits(s, (STATIC_TREES<<1)+eof, 3);
+ compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
+ s->compressed_len += 3 + s->static_len;
+ } else {
+ send_bits(s, (DYN_TREES<<1)+eof, 3);
+ send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
+ max_blindex+1);
+ compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
+ s->compressed_len += 3 + s->opt_len;
+ }
+ Assert (s->compressed_len == s->bits_sent, "bad compressed size");
+ init_block(s);
+
+ if (eof) {
+ bi_windup(s);
+ s->compressed_len += 7; /* align on byte boundary */
+ }
+ Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
+ s->compressed_len-7*eof));
+
+ return s->compressed_len >> 3;
+}
+
+/* ===========================================================================
+ * Save the match info and tally the frequency counts. Return true if
+ * the current block must be flushed.
+ */
+int zlib_tr_tally(
+ deflate_state *s,
+ unsigned dist, /* distance of matched string */
+ unsigned lc /* match length-MIN_MATCH or unmatched char (if dist==0) */
+)
+{
+ s->d_buf[s->last_lit] = (ush)dist;
+ s->l_buf[s->last_lit++] = (uch)lc;
+ if (dist == 0) {
+ /* lc is the unmatched char */
+ s->dyn_ltree[lc].Freq++;
+ } else {
+ s->matches++;
+ /* Here, lc is the match length - MIN_MATCH */
+ dist--; /* dist = match distance - 1 */
+ Assert((ush)dist < (ush)MAX_DIST(s) &&
+ (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
+ (ush)d_code(dist) < (ush)D_CODES, "zlib_tr_tally: bad match");
+
+ s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
+ s->dyn_dtree[d_code(dist)].Freq++;
+ }
+
+ /* Try to guess if it is profitable to stop the current block here */
+ if ((s->last_lit & 0xfff) == 0 && s->level > 2) {
+ /* Compute an upper bound for the compressed length */
+ ulg out_length = (ulg)s->last_lit*8L;
+ ulg in_length = (ulg)((long)s->strstart - s->block_start);
+ int dcode;
+ for (dcode = 0; dcode < D_CODES; dcode++) {
+ out_length += (ulg)s->dyn_dtree[dcode].Freq *
+ (5L+extra_dbits[dcode]);
+ }
+ out_length >>= 3;
+ Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ",
+ s->last_lit, in_length, out_length,
+ 100L - out_length*100L/in_length));
+ if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1;
+ }
+ return (s->last_lit == s->lit_bufsize-1);
+ /* 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(
+ deflate_state *s,
+ ct_data *ltree, /* literal tree */
+ ct_data *dtree /* distance tree */
+)
+{
+ 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 code; /* the code to send */
+ int extra; /* number of extra bits to send */
+
+ if (s->last_lit != 0) do {
+ dist = s->d_buf[lx];
+ lc = s->l_buf[lx++];
+ if (dist == 0) {
+ send_code(s, 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(s, code+LITERALS+1, ltree); /* send the length code */
+ extra = extra_lbits[code];
+ if (extra != 0) {
+ lc -= base_length[code];
+ send_bits(s, lc, extra); /* send the extra length bits */
+ }
+ dist--; /* dist is now the match distance - 1 */
+ code = d_code(dist);
+ Assert (code < D_CODES, "bad d_code");
+
+ send_code(s, code, dtree); /* send the distance code */
+ extra = extra_dbits[code];
+ if (extra != 0) {
+ dist -= base_dist[code];
+ send_bits(s, dist, extra); /* send the extra distance bits */
+ }
+ } /* literal or match pair ? */
+
+ /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */
+ Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow");
+
+ } while (lx < s->last_lit);
+
+ send_code(s, END_BLOCK, ltree);
+ s->last_eob_len = ltree[END_BLOCK].Len;
+}
+
+/* ===========================================================================
+ * Set the data 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).
+ */
+static void set_data_type(
+ deflate_state *s
+)
+{
+ int n = 0;
+ unsigned ascii_freq = 0;
+ unsigned bin_freq = 0;
+ while (n < 7) bin_freq += s->dyn_ltree[n++].Freq;
+ while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq;
+ while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq;
+ s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII);
+}
+
+/* ===========================================================================
+ * Copy a stored block, storing first the length and its
+ * one's complement if requested.
+ */
+static void copy_block(
+ deflate_state *s,
+ char *buf, /* the input data */
+ unsigned len, /* its length */
+ int header /* true if block header must be written */
+)
+{
+ bi_windup(s); /* align on byte boundary */
+ s->last_eob_len = 8; /* enough lookahead for inflate */
+
+ if (header) {
+ put_short(s, (ush)len);
+ put_short(s, (ush)~len);
+#ifdef DEBUG_ZLIB
+ s->bits_sent += 2*16;
+#endif
+ }
+#ifdef DEBUG_ZLIB
+ s->bits_sent += (ulg)len<<3;
+#endif
+ /* bundle up the put_byte(s, *buf++) calls */
+ memcpy(&s->pending_buf[s->pending], buf, len);
+ s->pending += len;
+}
+
diff --git a/lib/zlib_deflate/defutil.h b/lib/zlib_deflate/defutil.h
new file mode 100644
index 0000000..d9feaf6
--- /dev/null
+++ b/lib/zlib_deflate/defutil.h
@@ -0,0 +1,334 @@
+
+
+
+#define Assert(err, str)
+#define Trace(dummy)
+#define Tracev(dummy)
+#define Tracecv(err, dummy)
+#define Tracevv(dummy)
+
+
+
+#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 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 */
+
+#define HEAP_SIZE (2*L_CODES+1)
+/* maximum heap size */
+
+#define MAX_BITS 15
+/* All codes must not exceed MAX_BITS bits */
+
+#define INIT_STATE 42
+#define BUSY_STATE 113
+#define FINISH_STATE 666
+/* Stream status */
+
+
+/* Data structure describing a single value and its code string. */
+typedef struct ct_data_s {
+ 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
+
+typedef struct static_tree_desc_s static_tree_desc;
+
+typedef struct tree_desc_s {
+ ct_data *dyn_tree; /* the dynamic tree */
+ int max_code; /* largest code with non zero frequency */
+ static_tree_desc *stat_desc; /* the corresponding static tree */
+} tree_desc;
+
+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.
+ */
+
+typedef struct deflate_state {
+ z_streamp strm; /* pointer back to this zlib stream */
+ int status; /* as the name implies */
+ Byte *pending_buf; /* output still pending */
+ ulg pending_buf_size; /* size of pending_buf */
+ Byte *pending_out; /* next pending byte to output to the stream */
+ int pending; /* nb of bytes in the pending buffer */
+ int noheader; /* suppress zlib header and adler32 */
+ Byte data_type; /* UNKNOWN, BINARY or ASCII */
+ Byte method; /* STORED (for zip only) or DEFLATED */
+ int last_flush; /* value of flush param for previous deflate call */
+
+ /* used by deflate.c: */
+
+ uInt w_size; /* LZ77 window size (32K by default) */
+ uInt w_bits; /* log2(w_size) (8..16) */
+ uInt w_mask; /* w_size - 1 */
+
+ Byte *window;
+ /* 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: use the user input buffer as sliding window.
+ */
+
+ ulg window_size;
+ /* Actual size of window: 2*wSize, except when the user input buffer
+ * is directly used as sliding window.
+ */
+
+ Pos *prev;
+ /* 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.
+ */
+
+ Pos *head; /* Heads of the hash chains or NIL. */
+
+ uInt ins_h; /* hash index of string to be inserted */
+ uInt hash_size; /* number of elements in hash table */
+ uInt hash_bits; /* log2(hash_size) */
+ uInt hash_mask; /* hash_size-1 */
+
+ uInt hash_shift;
+ /* Number of bits by which ins_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:
+ * hash_shift * MIN_MATCH >= hash_bits
+ */
+
+ long block_start;
+ /* Window position at the beginning of the current output block. Gets
+ * negative when the window is moved backwards.
+ */
+
+ uInt match_length; /* length of best match */
+ IPos prev_match; /* previous match */
+ int match_available; /* set if previous match exists */
+ uInt strstart; /* start of string to insert */
+ uInt match_start; /* start of matching string */
+ uInt lookahead; /* number of valid bytes ahead in window */
+
+ uInt 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.
+ */
+
+ uInt max_chain_length;
+ /* To speed up deflation, hash chains are never searched beyond this
+ * length. A higher limit improves compression ratio but degrades the
+ * speed.
+ */
+
+ uInt max_lazy_match;
+ /* 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.
+ */
+# define 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.
+ */
+
+ int level; /* compression level (1..9) */
+ int strategy; /* favor or force Huffman coding*/
+
+ uInt good_match;
+ /* Use a faster search when the previous match is longer than this */
+
+ int nice_match; /* Stop searching when current match exceeds this */
+
+ /* used by trees.c: */
+ /* Didn't use ct_data typedef below to supress compiler warning */
+ struct ct_data_s dyn_ltree[HEAP_SIZE]; /* literal and length tree */
+ struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
+ struct ct_data_s bl_tree[2*BL_CODES+1]; /* Huffman tree for bit lengths */
+
+ struct tree_desc_s l_desc; /* desc. for literal tree */
+ struct tree_desc_s d_desc; /* desc. for distance tree */
+ struct tree_desc_s bl_desc; /* desc. for bit length tree */
+
+ ush bl_count[MAX_BITS+1];
+ /* number of codes at each bit length for an optimal tree */
+
+ int heap[2*L_CODES+1]; /* 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.
+ */
+
+ uch depth[2*L_CODES+1];
+ /* Depth of each subtree used as tie breaker for trees of equal frequency
+ */
+
+ uch *l_buf; /* buffer for literals or lengths */
+
+ uInt lit_bufsize;
+ /* Size of match buffer for literals/lengths. 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).
+ * This is applicable only for zip (not gzip or zlib).
+ * - 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
+ */
+
+ uInt last_lit; /* running index in l_buf */
+
+ ush *d_buf;
+ /* Buffer for distances. To simplify the code, d_buf and l_buf have
+ * the same number of elements. To use different lengths, an extra flag
+ * array would be necessary.
+ */
+
+ 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 */
+ uInt matches; /* number of string matches in current block */
+ int last_eob_len; /* bit length of EOB code for last block */
+
+#ifdef DEBUG_ZLIB
+ ulg bits_sent; /* bit length of the compressed data */
+#endif
+
+ ush bi_buf;
+ /* Output buffer. bits are inserted starting at the bottom (least
+ * significant bits).
+ */
+ int bi_valid;
+ /* Number of valid bits in bi_buf. All bits above the last valid bit
+ * are always zero.
+ */
+
+} deflate_state;
+
+typedef struct deflate_workspace {
+ /* State memory for the deflator */
+ deflate_state deflate_memory;
+ Byte window_memory[2 * (1 << MAX_WBITS)];
+ Pos prev_memory[1 << MAX_WBITS];
+ Pos head_memory[1 << (MAX_MEM_LEVEL + 7)];
+ char overlay_memory[(1 << (MAX_MEM_LEVEL + 6)) * (sizeof(ush)+2)];
+} deflate_workspace;
+
+/* Output a byte on the stream.
+ * IN assertion: there is enough room in pending_buf.
+ */
+#define put_byte(s, c) {s->pending_buf[s->pending++] = (c);}
+
+
+#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(s) ((s)->w_size-MIN_LOOKAHEAD)
+/* In order to simplify the code, particularly on 16 bit machines, match
+ * distances are limited to MAX_DIST instead of WSIZE.
+ */
+
+ /* in trees.c */
+void zlib_tr_init (deflate_state *s);
+int zlib_tr_tally (deflate_state *s, unsigned dist, unsigned lc);
+ulg zlib_tr_flush_block (deflate_state *s, char *buf, ulg stored_len,
+ int eof);
+void zlib_tr_align (deflate_state *s);
+void zlib_tr_stored_block (deflate_state *s, char *buf, ulg stored_len,
+ int eof);
+void zlib_tr_stored_type_only (deflate_state *);
+
+
+/* ===========================================================================
+ * Output a short LSB first on the stream.
+ * IN assertion: there is enough room in pendingBuf.
+ */
+#define put_short(s, w) { \
+ put_byte(s, (uch)((w) & 0xff)); \
+ put_byte(s, (uch)((ush)(w) >> 8)); \
+}
+
+/* ===========================================================================
+ * Reverse the first len bits of a code, using straightforward code (a faster
+ * method would use a table)
+ * IN assertion: 1 <= len <= 15
+ */
+static inline unsigned bi_reverse(unsigned code, /* the value to invert */
+ int len) /* its bit length */
+{
+ register unsigned res = 0;
+ do {
+ res |= code & 1;
+ code >>= 1, res <<= 1;
+ } while (--len > 0);
+ return res >> 1;
+}
+
+/* ===========================================================================
+ * Flush the bit buffer, keeping at most 7 bits in it.
+ */
+static inline void bi_flush(deflate_state *s)
+{
+ if (s->bi_valid == 16) {
+ put_short(s, s->bi_buf);
+ s->bi_buf = 0;
+ s->bi_valid = 0;
+ } else if (s->bi_valid >= 8) {
+ put_byte(s, (Byte)s->bi_buf);
+ s->bi_buf >>= 8;
+ s->bi_valid -= 8;
+ }
+}
+
+/* ===========================================================================
+ * Flush the bit buffer and align the output on a byte boundary
+ */
+static inline void bi_windup(deflate_state *s)
+{
+ if (s->bi_valid > 8) {
+ put_short(s, s->bi_buf);
+ } else if (s->bi_valid > 0) {
+ put_byte(s, (Byte)s->bi_buf);
+ }
+ s->bi_buf = 0;
+ s->bi_valid = 0;
+#ifdef DEBUG_ZLIB
+ s->bits_sent = (s->bits_sent+7) & ~7;
+#endif
+}
+