1 files changed, 78 insertions, 30 deletions
diff --git a/src/Common/zlib/deflate.c b/src/Common/zlib/deflate.c
index 1ec76144..799fb93c 100644
--- a/src/Common/zlib/deflate.c
+++ b/src/Common/zlib/deflate.c
@@ -1,90 +1,90 @@
 /* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
+ * Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler
  * 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 http://tools.ietf.org/html/rfc1951
  *
  *      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
  *
  */
 
 /* @(#) $Id$ */
 
 #include "deflate.h"
 
 const char deflate_copyright[] =
-   " deflate 1.2.11 Copyright 1995-2017 Jean-loup Gailly and Mark Adler ";
+   " deflate 1.2.12 Copyright 1995-2022 Jean-loup Gailly and Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
   include such an acknowledgment, I would appreciate that you keep this
   copyright string in the executable of your product.
  */
 
 /* ===========================================================================
  *  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) OF((deflate_state *s, int flush));
 /* Compression function. Returns the block state after the call. */
 
 local int deflateStateCheck      OF((z_streamp strm));
 local void slide_hash     OF((deflate_state *s));
 local void fill_window    OF((deflate_state *s));
 local block_state deflate_stored OF((deflate_state *s, int flush));
 local block_state deflate_fast   OF((deflate_state *s, int flush));
 #ifndef FASTEST
 local block_state deflate_slow   OF((deflate_state *s, int flush));
 #endif
 local block_state deflate_rle    OF((deflate_state *s, int flush));
 local block_state deflate_huff   OF((deflate_state *s, int flush));
 local void lm_init        OF((deflate_state *s));
 local void putShortMSB    OF((deflate_state *s, uInt b));
 local void flush_pending  OF((z_streamp strm));
 local unsigned read_buf   OF((z_streamp strm, Bytef *buf, unsigned size));
 #ifdef ASMV
@@ -158,219 +158,259 @@ local const config configuration_table[10] = {
  * Update a hash value with the given input byte
  * IN  assertion: all calls 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.
  * If this file is compiled with -DFASTEST, the compression level is forced
  * to 1, and no hash chains are maintained.
  * IN  assertion: all calls 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).
  */
 #ifdef FASTEST
 #define INSERT_STRING(s, str, match_head) \
    (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
     match_head = s->head[s->ins_h], \
     s->head[s->ins_h] = (Pos)(str))
 #else
 #define INSERT_STRING(s, str, match_head) \
    (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
     match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \
     s->head[s->ins_h] = (Pos)(str))
 #endif
 
 /* ===========================================================================
  * 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; \
-    zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
+    do { \
+        s->head[s->hash_size-1] = NIL; \
+        zmemzero((Bytef *)s->head, \
+                 (unsigned)(s->hash_size-1)*sizeof(*s->head)); \
+    } while (0)
 
 /* ===========================================================================
  * Slide the hash table when sliding the window down (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.
  */
 local void slide_hash(s)
     deflate_state *s;
 {
     unsigned n, m;
     Posf *p;
     uInt wsize = s->w_size;
 
     n = s->hash_size;
     p = &s->head[n];
     do {
         m = *--p;
         *p = (Pos)(m >= wsize ? m - wsize : NIL);
     } while (--n);
     n = wsize;
 #ifndef FASTEST
     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);
 #endif
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateInit_(strm, level, version, stream_size)
     z_streamp strm;
     int level;
     const char *version;
     int stream_size;
 {
     return 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 ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
                   version, stream_size)
     z_streamp strm;
     int  level;
     int  method;
     int  windowBits;
     int  memLevel;
     int  strategy;
     const char *version;
     int stream_size;
 {
     deflate_state *s;
     int wrap = 1;
     static const char my_version[] = ZLIB_VERSION;
 
-    ushf *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 == Z_NULL || version[0] != my_version[0] ||
         stream_size != sizeof(z_stream)) {
         return Z_VERSION_ERROR;
     }
     if (strm == Z_NULL) return Z_STREAM_ERROR;
 
     strm->msg = Z_NULL;
     if (strm->zalloc == (alloc_func)0) {
 #ifdef Z_SOLO
         return Z_STREAM_ERROR;
 #else
         strm->zalloc = zcalloc;
         strm->opaque = (voidpf)0;
 #endif
     }
     if (strm->zfree == (free_func)0)
 #ifdef Z_SOLO
         return Z_STREAM_ERROR;
 #else
         strm->zfree = zcfree;
 #endif
 
 #ifdef FASTEST
     if (level != 0) level = 1;
 #else
     if (level == Z_DEFAULT_COMPRESSION) level = 6;
 #endif
 
     if (windowBits < 0) { /* suppress zlib wrapper */
         wrap = 0;
         windowBits = -windowBits;
     }
 #ifdef GZIP
     else if (windowBits > 15) {
         wrap = 2;       /* write gzip wrapper instead */
         windowBits -= 16;
     }
 #endif
     if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||
         windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||
         strategy < 0 || strategy > Z_FIXED || (windowBits == 8 && wrap != 1)) {
         return Z_STREAM_ERROR;
     }
     if (windowBits == 8) windowBits = 9;  /* until 256-byte window bug fixed */
     s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));
     if (s == Z_NULL) return Z_MEM_ERROR;
     strm->state = (struct internal_state FAR *)s;
     s->strm = strm;
     s->status = INIT_STATE;     /* to pass state test in deflateReset() */
 
     s->wrap = wrap;
     s->gzhead = Z_NULL;
     s->w_bits = (uInt)windowBits;
     s->w_size = 1 << s->w_bits;
     s->w_mask = s->w_size - 1;
 
     s->hash_bits = (uInt)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 = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));
     s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));
     s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));
 
     s->high_water = 0;      /* nothing written to s->window yet */
 
     s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
 
-    overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
-    s->pending_buf = (uchf *) overlay;
-    s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);
+    /* We overlay pending_buf and sym_buf. This works since the average size
+     * for length/distance pairs over any compressed block is assured to be 31
+     * bits or less.
+     *
+     * Analysis: The longest fixed codes are a length code of 8 bits plus 5
+     * extra bits, for lengths 131 to 257. The longest fixed distance codes are
+     * 5 bits plus 13 extra bits, for distances 16385 to 32768. The longest
+     * possible fixed-codes length/distance pair is then 31 bits total.
+     *
+     * sym_buf starts one-fourth of the way into pending_buf. So there are
+     * three bytes in sym_buf for every four bytes in pending_buf. Each symbol
+     * in sym_buf is three bytes -- two for the distance and one for the
+     * literal/length. As each symbol is consumed, the pointer to the next
+     * sym_buf value to read moves forward three bytes. From that symbol, up to
+     * 31 bits are written to pending_buf. The closest the written pending_buf
+     * bits gets to the next sym_buf symbol to read is just before the last
+     * code is written. At that time, 31*(n-2) bits have been written, just
+     * after 24*(n-2) bits have been consumed from sym_buf. sym_buf starts at
+     * 8*n bits into pending_buf. (Note that the symbol buffer fills when n-1
+     * symbols are written.) The closest the writing gets to what is unread is
+     * then n+14 bits. Here n is lit_bufsize, which is 16384 by default, and
+     * can range from 128 to 32768.
+     *
+     * Therefore, at a minimum, there are 142 bits of space between what is
+     * written and what is read in the overlain buffers, so the symbols cannot
+     * be overwritten by the compressed data. That space is actually 139 bits,
+     * due to the three-bit fixed-code block header.
+     *
+     * That covers the case where either Z_FIXED is specified, forcing fixed
+     * codes, or when the use of fixed codes is chosen, because that choice
+     * results in a smaller compressed block than dynamic codes. That latter
+     * condition then assures that the above analysis also covers all dynamic
+     * blocks. A dynamic-code block will only be chosen to be emitted if it has
+     * fewer bits than a fixed-code block would for the same set of symbols.
+     * Therefore its average symbol length is assured to be less than 31. So
+     * the compressed data for a dynamic block also cannot overwrite the
+     * symbols from which it is being constructed.
+     */
+
+    s->pending_buf = (uchf *) ZALLOC(strm, s->lit_bufsize, 4);
+    s->pending_buf_size = (ulg)s->lit_bufsize * 4;
 
     if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
         s->pending_buf == Z_NULL) {
         s->status = FINISH_STATE;
         strm->msg = ERR_MSG(Z_MEM_ERROR);
         deflateEnd (strm);
         return Z_MEM_ERROR;
     }
-    s->d_buf = overlay + s->lit_bufsize/sizeof(ush);
-    s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;
+    s->sym_buf = s->pending_buf + s->lit_bufsize;
+    s->sym_end = (s->lit_bufsize - 1) * 3;
+    /* We avoid equality with lit_bufsize*3 because of wraparound at 64K
+     * on 16 bit machines and because stored blocks are restricted to
+     * 64K-1 bytes.
+     */
 
     s->level = level;
     s->strategy = strategy;
     s->method = (Byte)method;
 
     return deflateReset(strm);
 }
 
 /* =========================================================================
  * Check for a valid deflate stream state. Return 0 if ok, 1 if not.
  */
 local int deflateStateCheck (strm)
     z_streamp strm;
 {
     deflate_state *s;
     if (strm == Z_NULL ||
         strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
         return 1;
     s = strm->state;
     if (s == Z_NULL || s->strm != strm || (s->status != INIT_STATE &&
 #ifdef GZIP
                                            s->status != GZIP_STATE &&
 #endif
                                            s->status != EXTRA_STATE &&
                                            s->status != NAME_STATE &&
                                            s->status != COMMENT_STATE &&
                                            s->status != HCRC_STATE &&
                                            s->status != BUSY_STATE &&
                                            s->status != FINISH_STATE))
         return 1;
     return 0;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
@@ -456,175 +496,176 @@ int ZEXPORT deflateGetDictionary (strm, dictionary, dictLength)
     len = s->strstart + s->lookahead;
     if (len > s->w_size)
         len = s->w_size;
     if (dictionary != Z_NULL && len)
         zmemcpy(dictionary, s->window + s->strstart + s->lookahead - len, len);
     if (dictLength != Z_NULL)
         *dictLength = len;
     return Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateResetKeep (strm)
     z_streamp strm;
 {
     deflate_state *s;
 
     if (deflateStateCheck(strm)) {
         return Z_STREAM_ERROR;
     }
 
     strm->total_in = strm->total_out = 0;
     strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */
     strm->data_type = Z_UNKNOWN;
 
     s = (deflate_state *)strm->state;
     s->pending = 0;
     s->pending_out = s->pending_buf;
 
     if (s->wrap < 0) {
         s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */
     }
     s->status =
 #ifdef GZIP
         s->wrap == 2 ? GZIP_STATE :
 #endif
-        s->wrap ? INIT_STATE : BUSY_STATE;
+        INIT_STATE;
     strm->adler =
 #ifdef GZIP
         s->wrap == 2 ? crc32(0L, Z_NULL, 0) :
 #endif
         adler32(0L, Z_NULL, 0);
-    s->last_flush = Z_NO_FLUSH;
+    s->last_flush = -2;
 
     _tr_init(s);
 
     return Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateReset (strm)
     z_streamp strm;
 {
     int ret;
 
     ret = deflateResetKeep(strm);
     if (ret == Z_OK)
         lm_init(strm->state);
     return ret;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateSetHeader (strm, head)
     z_streamp strm;
     gz_headerp head;
 {
     if (deflateStateCheck(strm) || strm->state->wrap != 2)
         return Z_STREAM_ERROR;
     strm->state->gzhead = head;
     return Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflatePending (strm, pending, bits)
     unsigned *pending;
     int *bits;
     z_streamp strm;
 {
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
     if (pending != Z_NULL)
         *pending = strm->state->pending;
     if (bits != Z_NULL)
         *bits = strm->state->bi_valid;
     return Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflatePrime (strm, bits, value)
     z_streamp strm;
     int bits;
     int value;
 {
     deflate_state *s;
     int put;
 
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
     s = strm->state;
-    if ((Bytef *)(s->d_buf) < s->pending_out + ((Buf_size + 7) >> 3))
+    if (bits < 0 || bits > 16 ||
+        s->sym_buf < s->pending_out + ((Buf_size + 7) >> 3))
         return Z_BUF_ERROR;
     do {
         put = Buf_size - s->bi_valid;
         if (put > bits)
             put = bits;
         s->bi_buf |= (ush)((value & ((1 << put) - 1)) << s->bi_valid);
         s->bi_valid += put;
         _tr_flush_bits(s);
         value >>= put;
         bits -= put;
     } while (bits);
     return Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateParams(strm, level, strategy)
     z_streamp strm;
     int level;
     int strategy;
 {
     deflate_state *s;
     compress_func func;
 
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
     s = strm->state;
 
 #ifdef FASTEST
     if (level != 0) level = 1;
 #else
     if (level == Z_DEFAULT_COMPRESSION) level = 6;
 #endif
     if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) {
         return Z_STREAM_ERROR;
     }
     func = configuration_table[s->level].func;
 
     if ((strategy != s->strategy || func != configuration_table[level].func) &&
-        s->high_water) {
+        s->last_flush != -2) {
         /* Flush the last buffer: */
         int err = deflate(strm, Z_BLOCK);
         if (err == Z_STREAM_ERROR)
             return err;
-        if (strm->avail_out == 0)
+        if (strm->avail_in || (s->strstart - s->block_start) + s->lookahead)
             return Z_BUF_ERROR;
     }
     if (s->level != level) {
         if (s->level == 0 && s->matches != 0) {
             if (s->matches == 1)
                 slide_hash(s);
             else
                 CLEAR_HASH(s);
             s->matches = 0;
         }
         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 Z_OK;
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
     z_streamp strm;
     int good_length;
     int max_lazy;
     int nice_length;
     int max_chain;
 {
     deflate_state *s;
 
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
     s = strm->state;
     s->good_match = (uInt)good_length;
     s->max_lazy_match = (uInt)max_lazy;
     s->nice_match = nice_length;
@@ -779,70 +820,72 @@ int ZEXPORT deflate (strm, flush)
     }
     if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);
 
     old_flush = s->last_flush;
     s->last_flush = flush;
 
     /* 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_BUF_ERROR.
      */
     } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) &&
                flush != Z_FINISH) {
         ERR_RETURN(strm, Z_BUF_ERROR);
     }
 
     /* User must not provide more input after the first FINISH: */
     if (s->status == FINISH_STATE && strm->avail_in != 0) {
         ERR_RETURN(strm, Z_BUF_ERROR);
     }
 
     /* Write the header */
+    if (s->status == INIT_STATE && s->wrap == 0)
+        s->status = BUSY_STATE;
     if (s->status == INIT_STATE) {
         /* zlib header */
         uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;
         uInt level_flags;
 
         if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2)
             level_flags = 0;
         else if (s->level < 6)
             level_flags = 1;
         else if (s->level == 6)
             level_flags = 2;
         else
             level_flags = 3;
         header |= (level_flags << 6);
         if (s->strstart != 0) header |= PRESET_DICT;
         header += 31 - (header % 31);
 
         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 = adler32(0L, Z_NULL, 0);
         s->status = BUSY_STATE;
 
         /* Compression must start with an empty pending buffer */
         flush_pending(strm);
         if (s->pending != 0) {
             s->last_flush = -1;
             return Z_OK;
         }
     }
 #ifdef GZIP
@@ -1076,107 +1119,104 @@ int ZEXPORT deflate (strm, flush)
 int ZEXPORT deflateEnd (strm)
     z_streamp strm;
 {
     int status;
 
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
 
     status = strm->state->status;
 
     /* Deallocate in reverse order of allocations: */
     TRY_FREE(strm, strm->state->pending_buf);
     TRY_FREE(strm, strm->state->head);
     TRY_FREE(strm, strm->state->prev);
     TRY_FREE(strm, strm->state->window);
 
     ZFREE(strm, strm->state);
     strm->state = Z_NULL;
 
     return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
 }
 
 /* =========================================================================
  * Copy the source state to the destination state.
  * To simplify the source, this is not supported for 16-bit MSDOS (which
  * doesn't have enough memory anyway to duplicate compression states).
  */
 int ZEXPORT deflateCopy (dest, source)
     z_streamp dest;
     z_streamp source;
 {
 #ifdef MAXSEG_64K
     return Z_STREAM_ERROR;
 #else
     deflate_state *ds;
     deflate_state *ss;
-    ushf *overlay;
 
 
     if (deflateStateCheck(source) || dest == Z_NULL) {
         return Z_STREAM_ERROR;
     }
 
     ss = source->state;
 
     zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
 
     ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));
     if (ds == Z_NULL) return Z_MEM_ERROR;
     dest->state = (struct internal_state FAR *) ds;
     zmemcpy((voidpf)ds, (voidpf)ss, sizeof(deflate_state));
     ds->strm = dest;
 
     ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
     ds->prev   = (Posf *)  ZALLOC(dest, ds->w_size, sizeof(Pos));
     ds->head   = (Posf *)  ZALLOC(dest, ds->hash_size, sizeof(Pos));
-    overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);
-    ds->pending_buf = (uchf *) overlay;
+    ds->pending_buf = (uchf *) ZALLOC(dest, ds->lit_bufsize, 4);
 
     if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
         ds->pending_buf == Z_NULL) {
         deflateEnd (dest);
         return Z_MEM_ERROR;
     }
     /* following zmemcpy do not work for 16-bit MSDOS */
     zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
     zmemcpy((voidpf)ds->prev, (voidpf)ss->prev, ds->w_size * sizeof(Pos));
     zmemcpy((voidpf)ds->head, (voidpf)ss->head, ds->hash_size * sizeof(Pos));
     zmemcpy(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->sym_buf = ds->pending_buf + 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 /* MAXSEG_64K */
 }
 
 /* ===========================================================================
  * 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()).
  */
 local unsigned read_buf(strm, buf, size)
     z_streamp strm;
     Bytef *buf;
     unsigned size;
 {
     unsigned len = strm->avail_in;
 
     if (len > size) len = size;
     if (len == 0) return 0;
 
     strm->avail_in  -= len;
 
     zmemcpy(buf, strm->next_in, len);
     if (strm->state->wrap == 1) {
         strm->adler = adler32(strm->adler, buf, len);
     }
 #ifdef GZIP
     else if (strm->state->wrap == 2) {
         strm->adler = crc32(strm->adler, buf, len);
@@ -1481,70 +1521,72 @@ local void check_match(s, start, match, length)
  */
 local void fill_window(s)
     deflate_state *s;
 {
     unsigned n;
     unsigned more;    /* Amount of free space at the end of the window. */
     uInt wsize = s->w_size;
 
     Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead");
 
     do {
         more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
 
         /* Deal with !@#$% 64K limit: */
         if (sizeof(int) <= 2) {
             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 && lookahead == 1 (input done a 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.
          */
         if (s->strstart >= wsize+MAX_DIST(s)) {
 
             zmemcpy(s->window, s->window+wsize, (unsigned)wsize - more);
             s->match_start -= wsize;
             s->strstart    -= wsize; /* we now have strstart >= MAX_DIST */
             s->block_start -= (long) wsize;
+            if (s->insert > s->strstart)
+                s->insert = s->strstart;
             slide_hash(s);
             more += wsize;
         }
         if (s->strm->avail_in == 0) break;
 
         /* 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 + s->insert >= MIN_MATCH) {
             uInt str = s->strstart - s->insert;
             s->ins_h = s->window[str];
             UPDATE_HASH(s, s->ins_h, s->window[str + 1]);
 #if MIN_MATCH != 3
             Call UPDATE_HASH() MIN_MATCH-3 more times
 #endif
             while (s->insert) {
                 UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]);
 #ifndef FASTEST
                 s->prev[str & s->w_mask] = s->head[s->ins_h];
 #endif
                 s->head[s->ins_h] = (Pos)str;
@@ -1710,113 +1752,119 @@ local block_state deflate_stored(s, flush)
                 left = len;
             zmemcpy(s->strm->next_out, s->window + s->block_start, left);
             s->strm->next_out += left;
             s->strm->avail_out -= left;
             s->strm->total_out += left;
             s->block_start += left;
             len -= left;
         }
 
         /* Copy uncompressed bytes directly from next_in to next_out, updating
          * the check value.
          */
         if (len) {
             read_buf(s->strm, s->strm->next_out, len);
             s->strm->next_out += len;
             s->strm->avail_out -= len;
             s->strm->total_out += len;
         }
     } while (last == 0);
 
     /* Update the sliding window with the last s->w_size bytes of the copied
      * data, or append all of the copied data to the existing window if less
      * than s->w_size bytes were copied. Also update the number of bytes to
      * insert in the hash tables, in the event that deflateParams() switches to
      * a non-zero compression level.
      */
     used -= s->strm->avail_in;      /* number of input bytes directly copied */
     if (used) {
         /* If any input was used, then no unused input remains in the window,
          * therefore s->block_start == s->strstart.
          */
         if (used >= s->w_size) {    /* supplant the previous history */
             s->matches = 2;         /* clear hash */
             zmemcpy(s->window, s->strm->next_in - s->w_size, s->w_size);
             s->strstart = s->w_size;
+            s->insert = s->strstart;
         }
         else {
             if (s->window_size - s->strstart <= used) {
                 /* Slide the window down. */
                 s->strstart -= s->w_size;
                 zmemcpy(s->window, s->window + s->w_size, s->strstart);
                 if (s->matches < 2)
                     s->matches++;   /* add a pending slide_hash() */
+                if (s->insert > s->strstart)
+                    s->insert = s->strstart;
             }
             zmemcpy(s->window + s->strstart, s->strm->next_in - used, used);
             s->strstart += used;
+            s->insert += MIN(used, s->w_size - s->insert);
         }
         s->block_start = s->strstart;
-        s->insert += MIN(used, s->w_size - s->insert);
     }
     if (s->high_water < s->strstart)
         s->high_water = s->strstart;
 
     /* If the last block was written to next_out, then done. */
     if (last)
         return finish_done;
 
     /* If flushing and all input has been consumed, then done. */
     if (flush != Z_NO_FLUSH && flush != Z_FINISH &&
         s->strm->avail_in == 0 && (long)s->strstart == s->block_start)
         return block_done;
 
     /* Fill the window with any remaining input. */
-    have = s->window_size - s->strstart - 1;
+    have = s->window_size - s->strstart;
     if (s->strm->avail_in > have && s->block_start >= (long)s->w_size) {
         /* Slide the window down. */
         s->block_start -= s->w_size;
         s->strstart -= s->w_size;
         zmemcpy(s->window, s->window + s->w_size, s->strstart);
         if (s->matches < 2)
             s->matches++;           /* add a pending slide_hash() */
         have += s->w_size;          /* more space now */
+        if (s->insert > s->strstart)
+            s->insert = s->strstart;
     }
     if (have > s->strm->avail_in)
         have = s->strm->avail_in;
     if (have) {
         read_buf(s->strm, s->window + s->strstart, have);
         s->strstart += have;
+        s->insert += MIN(have, s->w_size - s->insert);
     }
     if (s->high_water < s->strstart)
         s->high_water = s->strstart;
 
     /* There was not enough avail_out to write a complete worthy or flushed
      * stored block to next_out. Write a stored block to pending instead, if we
      * have enough input for a worthy block, or if flushing and there is enough
      * room for the remaining input as a stored block in the pending buffer.
      */
     have = (s->bi_valid + 42) >> 3;         /* number of header bytes */
         /* maximum stored block length that will fit in pending: */
     have = MIN(s->pending_buf_size - have, MAX_STORED);
     min_block = MIN(have, s->w_size);
     left = s->strstart - s->block_start;
     if (left >= min_block ||
         ((left || flush == Z_FINISH) && flush != Z_NO_FLUSH &&
          s->strm->avail_in == 0 && left <= have)) {
         len = MIN(left, have);
         last = flush == Z_FINISH && s->strm->avail_in == 0 &&
                len == left ? 1 : 0;
         _tr_stored_block(s, (charf *)s->window + s->block_start, len, last);
         s->block_start += len;
         flush_pending(s->strm);
     }
 
     /* We've done all we can with the available input and output. */
     return last ? finish_started : need_more;
 }
 
 /* ===========================================================================
  * 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.
@@ -1880,71 +1928,71 @@ local block_state deflate_fast(s, flush)
                     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
 #endif
             {
                 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]));
             _tr_tally_lit (s, s->window[s->strstart], bflush);
             s->lookahead--;
             s->strstart++;
         }
         if (bflush) FLUSH_BLOCK(s, 0);
     }
     s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1;
     if (flush == Z_FINISH) {
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
 
 #ifndef FASTEST
 /* ===========================================================================
  * 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.
  */
 local block_state deflate_slow(s, flush)
     deflate_state *s;
     int flush;
 {
     IPos hash_head;          /* 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:
          */
@@ -2011,71 +2059,71 @@ local block_state deflate_slow(s, flush)
             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]));
             _tr_tally_lit(s, s->window[s->strstart-1], bflush);
             if (bflush) {
                 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]));
         _tr_tally_lit(s, s->window[s->strstart-1], bflush);
         s->match_available = 0;
     }
     s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1;
     if (flush == Z_FINISH) {
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
 #endif /* FASTEST */
 
 /* ===========================================================================
  * For Z_RLE, simply look for runs of bytes, generate matches only of distance
  * one.  Do not maintain a hash table.  (It will be regenerated if this run of
  * deflate switches away from Z_RLE.)
  */
 local block_state deflate_rle(s, flush)
     deflate_state *s;
     int flush;
 {
     int bflush;             /* set if current block must be flushed */
     uInt prev;              /* byte at distance one to match */
     Bytef *scan, *strend;   /* scan goes up to strend for length of run */
 
     for (;;) {
         /* Make sure that we always have enough lookahead, except
          * at the end of the input file. We need MAX_MATCH bytes
          * for the longest run, plus one for the unrolled loop.
          */
         if (s->lookahead <= MAX_MATCH) {
             fill_window(s);
             if (s->lookahead <= MAX_MATCH && flush == Z_NO_FLUSH) {
                 return need_more;
             }
             if (s->lookahead == 0) break; /* flush the current block */
         }
 
         /* See how many times the previous byte repeats */
         s->match_length = 0;
         if (s->lookahead >= MIN_MATCH && s->strstart > 0) {
             scan = s->window + s->strstart - 1;
@@ -2086,78 +2134,78 @@ local block_state deflate_rle(s, flush)
                 } while (prev == *++scan && prev == *++scan &&
                          prev == *++scan && prev == *++scan &&
                          prev == *++scan && prev == *++scan &&
                          prev == *++scan && prev == *++scan &&
                          scan < strend);
                 s->match_length = MAX_MATCH - (uInt)(strend - scan);
                 if (s->match_length > s->lookahead)
                     s->match_length = s->lookahead;
             }
             Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan");
         }
 
         /* Emit match if have run of MIN_MATCH or longer, else emit literal */
         if (s->match_length >= MIN_MATCH) {
             check_match(s, s->strstart, s->strstart - 1, s->match_length);
 
             _tr_tally_dist(s, 1, s->match_length - MIN_MATCH, bflush);
 
             s->lookahead -= s->match_length;
             s->strstart += s->match_length;
             s->match_length = 0;
         } else {
             /* No match, output a literal byte */
             Tracevv((stderr,"%c", s->window[s->strstart]));
             _tr_tally_lit (s, s->window[s->strstart], bflush);
             s->lookahead--;
             s->strstart++;
         }
         if (bflush) FLUSH_BLOCK(s, 0);
     }
     s->insert = 0;
     if (flush == Z_FINISH) {
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
 
 /* ===========================================================================
  * For Z_HUFFMAN_ONLY, do not look for matches.  Do not maintain a hash table.
  * (It will be regenerated if this run of deflate switches away from Huffman.)
  */
 local block_state deflate_huff(s, flush)
     deflate_state *s;
     int flush;
 {
     int bflush;             /* set if current block must be flushed */
 
     for (;;) {
         /* Make sure that we have a literal to write. */
         if (s->lookahead == 0) {
             fill_window(s);
             if (s->lookahead == 0) {
                 if (flush == Z_NO_FLUSH)
                     return need_more;
                 break;      /* flush the current block */
             }
         }
 
         /* Output a literal byte */
         s->match_length = 0;
         Tracevv((stderr,"%c", s->window[s->strstart]));
         _tr_tally_lit (s, s->window[s->strstart], bflush);
         s->lookahead--;
         s->strstart++;
         if (bflush) FLUSH_BLOCK(s, 0);
     }
     s->insert = 0;
     if (flush == Z_FINISH) {
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }