--- a/zlib/deflate.c	Sun Jun 15 15:39:16 2025 -0700
+++ b/zlib/deflate.c	Sun Jun 15 15:39:33 2025 -0700
@@ -1,5 +1,5 @@
 /* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler
+ * Copyright (C) 1995-2024 Jean-loup Gailly and Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -52,7 +52,7 @@
 #include "deflate.h"
 
 const char deflate_copyright[] =
-   " deflate 1.2.11 Copyright 1995-2017 Jean-loup Gailly and Mark Adler ";
+   " deflate 1.3.1 Copyright 1995-2024 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
@@ -60,9 +60,6 @@
   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 */
@@ -70,35 +67,16 @@
     finish_done     /* finish done, accept no more input or output */
 } block_state;
 
-typedef block_state (*compress_func) OF((deflate_state *s, int flush));
+typedef block_state (*compress_func)(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));
+local block_state deflate_stored(deflate_state *s, int flush);
+local block_state deflate_fast(deflate_state *s, int flush);
 #ifndef FASTEST
-local block_state deflate_slow   OF((deflate_state *s, int flush));
+local block_state deflate_slow(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
-#  pragma message("Assembler code may have bugs -- use at your own risk")
-      void match_init OF((void)); /* asm code initialization */
-      uInt longest_match  OF((deflate_state *s, IPos cur_match));
-#else
-local uInt longest_match  OF((deflate_state *s, IPos cur_match));
-#endif
-
-#ifdef ZLIB_DEBUG
-local  void check_match OF((deflate_state *s, IPos start, IPos match,
-                            int length));
-#endif
+local block_state deflate_rle(deflate_state *s, int flush);
+local block_state deflate_huff(deflate_state *s, int flush);
 
 /* ===========================================================================
  * Local data
@@ -160,7 +138,7 @@
  *    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)
+#define UPDATE_HASH(s,h,c) (h = (((h) << s->hash_shift) ^ (c)) & s->hash_mask)
 
 
 /* ===========================================================================
@@ -190,17 +168,23 @@
  * 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;
-{
+#if defined(__has_feature)
+#  if __has_feature(memory_sanitizer)
+     __attribute__((no_sanitize("memory")))
+#  endif
+#endif
+local void slide_hash(deflate_state *s) {
     unsigned n, m;
     Posf *p;
     uInt wsize = s->w_size;
@@ -224,39 +208,181 @@
 #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()).
+ */
+local unsigned read_buf(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);
+    }
+#endif
+    strm->next_in  += len;
+    strm->total_in += len;
+
+    return len;
+}
+
+/* ===========================================================================
+ * 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).
+ */
+local void fill_window(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;
+                str++;
+                s->insert--;
+                if (s->lookahead + s->insert < MIN_MATCH)
+                    break;
+            }
+        }
+        /* 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);
+
+    /* If the WIN_INIT bytes after the end of the current data have never been
+     * written, then zero those bytes in order to avoid memory check reports of
+     * the use of uninitialized (or uninitialised as Julian writes) bytes by
+     * the longest match routines.  Update the high water mark for the next
+     * time through here.  WIN_INIT is set to MAX_MATCH since the longest match
+     * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
+     */
+    if (s->high_water < s->window_size) {
+        ulg curr = s->strstart + (ulg)(s->lookahead);
+        ulg init;
+
+        if (s->high_water < curr) {
+            /* Previous high water mark below current data -- zero WIN_INIT
+             * bytes or up to end of window, whichever is less.
+             */
+            init = s->window_size - curr;
+            if (init > WIN_INIT)
+                init = WIN_INIT;
+            zmemzero(s->window + curr, (unsigned)init);
+            s->high_water = curr + init;
+        }
+        else if (s->high_water < (ulg)curr + WIN_INIT) {
+            /* High water mark at or above current data, but below current data
+             * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
+             * to end of window, whichever is less.
+             */
+            init = (ulg)curr + WIN_INIT - s->high_water;
+            if (init > s->window_size - s->high_water)
+                init = s->window_size - s->high_water;
+            zmemzero(s->window + s->high_water, (unsigned)init);
+            s->high_water += init;
+        }
+    }
+
+    Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
+           "not enough room for search");
+}
+
 /* ========================================================================= */
-int ZEXPORT deflateInit_(strm, level, version, stream_size)
-    z_streamp strm;
-    int level;
-    const char *version;
-    int stream_size;
-{
+int ZEXPORT deflateInit_(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;
-{
+int ZEXPORT deflateInit2_(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;
@@ -287,6 +413,8 @@
 
     if (windowBits < 0) { /* suppress zlib wrapper */
         wrap = 0;
+        if (windowBits < -15)
+            return Z_STREAM_ERROR;
         windowBits = -windowBits;
     }
 #ifdef GZIP
@@ -316,7 +444,7 @@
     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->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));
@@ -326,9 +454,47 @@
 
     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, LIT_BUFS);
+    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) {
@@ -337,8 +503,18 @@
         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;
+#ifdef LIT_MEM
+    s->d_buf = (ushf *)(s->pending_buf + (s->lit_bufsize << 1));
+    s->l_buf = s->pending_buf + (s->lit_bufsize << 2);
+    s->sym_end = s->lit_bufsize - 1;
+#else
+    s->sym_buf = s->pending_buf + s->lit_bufsize;
+    s->sym_end = (s->lit_bufsize - 1) * 3;
+#endif
+    /* 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;
@@ -350,9 +526,7 @@
 /* =========================================================================
  * Check for a valid deflate stream state. Return 0 if ok, 1 if not.
  */
-local int deflateStateCheck (strm)
-    z_streamp strm;
-{
+local int deflateStateCheck(z_streamp strm) {
     deflate_state *s;
     if (strm == Z_NULL ||
         strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
@@ -373,11 +547,8 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
-    z_streamp strm;
-    const Bytef *dictionary;
-    uInt  dictLength;
-{
+int ZEXPORT deflateSetDictionary(z_streamp strm, const Bytef *dictionary,
+                                 uInt  dictLength) {
     deflate_state *s;
     uInt str, n;
     int wrap;
@@ -442,11 +613,8 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateGetDictionary (strm, dictionary, dictLength)
-    z_streamp strm;
-    Bytef *dictionary;
-    uInt  *dictLength;
-{
+int ZEXPORT deflateGetDictionary(z_streamp strm, Bytef *dictionary,
+                                 uInt *dictLength) {
     deflate_state *s;
     uInt len;
 
@@ -464,9 +632,7 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateResetKeep (strm)
-    z_streamp strm;
-{
+int ZEXPORT deflateResetKeep(z_streamp strm) {
     deflate_state *s;
 
     if (deflateStateCheck(strm)) {
@@ -488,23 +654,45 @@
 #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;
 }
 
+/* ===========================================================================
+ * Initialize the "longest match" routines for a new zlib stream
+ */
+local 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->insert = 0;
+    s->match_length = s->prev_length = MIN_MATCH-1;
+    s->match_available = 0;
+    s->ins_h = 0;
+}
+
 /* ========================================================================= */
-int ZEXPORT deflateReset (strm)
-    z_streamp strm;
-{
+int ZEXPORT deflateReset(z_streamp strm) {
     int ret;
 
     ret = deflateResetKeep(strm);
@@ -514,10 +702,7 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateSetHeader (strm, head)
-    z_streamp strm;
-    gz_headerp head;
-{
+int ZEXPORT deflateSetHeader(z_streamp strm, gz_headerp head) {
     if (deflateStateCheck(strm) || strm->state->wrap != 2)
         return Z_STREAM_ERROR;
     strm->state->gzhead = head;
@@ -525,11 +710,7 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflatePending (strm, pending, bits)
-    unsigned *pending;
-    int *bits;
-    z_streamp strm;
-{
+int ZEXPORT deflatePending(z_streamp strm, unsigned *pending, int *bits) {
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
     if (pending != Z_NULL)
         *pending = strm->state->pending;
@@ -539,18 +720,21 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflatePrime (strm, bits, value)
-    z_streamp strm;
-    int bits;
-    int value;
-{
+int ZEXPORT deflatePrime(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))
+#ifdef LIT_MEM
+    if (bits < 0 || bits > 16 ||
+        (uchf *)s->d_buf < s->pending_out + ((Buf_size + 7) >> 3))
         return Z_BUF_ERROR;
+#else
+    if (bits < 0 || bits > 16 ||
+        s->sym_buf < s->pending_out + ((Buf_size + 7) >> 3))
+        return Z_BUF_ERROR;
+#endif
     do {
         put = Buf_size - s->bi_valid;
         if (put > bits)
@@ -565,11 +749,7 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateParams(strm, level, strategy)
-    z_streamp strm;
-    int level;
-    int strategy;
-{
+int ZEXPORT deflateParams(z_streamp strm, int level, int strategy) {
     deflate_state *s;
     compress_func func;
 
@@ -587,12 +767,12 @@
     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) {
@@ -614,13 +794,8 @@
 }
 
 /* ========================================================================= */
-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;
-{
+int ZEXPORT deflateTune(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;
@@ -633,36 +808,47 @@
 }
 
 /* =========================================================================
- * For the default windowBits of 15 and memLevel of 8, this function returns
- * a close to exact, as well as small, upper bound on the compressed size.
- * They are coded as constants here for a reason--if the #define's are
- * changed, then this function needs to be changed as well.  The return
- * value for 15 and 8 only works for those exact settings.
+ * For the default windowBits of 15 and memLevel of 8, this function returns a
+ * close to exact, as well as small, upper bound on the compressed size. This
+ * is an expansion of ~0.03%, plus a small constant.
+ *
+ * For any setting other than those defaults for windowBits and memLevel, one
+ * of two worst case bounds is returned. This is at most an expansion of ~4% or
+ * ~13%, plus a small constant.
  *
- * For any setting other than those defaults for windowBits and memLevel,
- * the value returned is a conservative worst case for the maximum expansion
- * resulting from using fixed blocks instead of stored blocks, which deflate
- * can emit on compressed data for some combinations of the parameters.
+ * Both the 0.03% and 4% derive from the overhead of stored blocks. The first
+ * one is for stored blocks of 16383 bytes (memLevel == 8), whereas the second
+ * is for stored blocks of 127 bytes (the worst case memLevel == 1). The
+ * expansion results from five bytes of header for each stored block.
+ *
+ * The larger expansion of 13% results from a window size less than or equal to
+ * the symbols buffer size (windowBits <= memLevel + 7). In that case some of
+ * the data being compressed may have slid out of the sliding window, impeding
+ * a stored block from being emitted. Then the only choice is a fixed or
+ * dynamic block, where a fixed block limits the maximum expansion to 9 bits
+ * per 8-bit byte, plus 10 bits for every block. The smallest block size for
+ * which this can occur is 255 (memLevel == 2).
  *
- * This function could be more sophisticated to provide closer upper bounds for
- * every combination of windowBits and memLevel.  But even the conservative
- * upper bound of about 14% expansion does not seem onerous for output buffer
- * allocation.
+ * Shifts are used to approximate divisions, for speed.
  */
-uLong ZEXPORT deflateBound(strm, sourceLen)
-    z_streamp strm;
-    uLong sourceLen;
-{
+uLong ZEXPORT deflateBound(z_streamp strm, uLong sourceLen) {
     deflate_state *s;
-    uLong complen, wraplen;
+    uLong fixedlen, storelen, wraplen;
+
+    /* upper bound for fixed blocks with 9-bit literals and length 255
+       (memLevel == 2, which is the lowest that may not use stored blocks) --
+       ~13% overhead plus a small constant */
+    fixedlen = sourceLen + (sourceLen >> 3) + (sourceLen >> 8) +
+               (sourceLen >> 9) + 4;
 
-    /* conservative upper bound for compressed data */
-    complen = sourceLen +
-              ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 5;
+    /* upper bound for stored blocks with length 127 (memLevel == 1) --
+       ~4% overhead plus a small constant */
+    storelen = sourceLen + (sourceLen >> 5) + (sourceLen >> 7) +
+               (sourceLen >> 11) + 7;
 
-    /* if can't get parameters, return conservative bound plus zlib wrapper */
+    /* if can't get parameters, return larger bound plus a zlib wrapper */
     if (deflateStateCheck(strm))
-        return complen + 6;
+        return (fixedlen > storelen ? fixedlen : storelen) + 6;
 
     /* compute wrapper length */
     s = strm->state;
@@ -699,11 +885,13 @@
         wraplen = 6;
     }
 
-    /* if not default parameters, return conservative bound */
+    /* if not default parameters, return one of the conservative bounds */
     if (s->w_bits != 15 || s->hash_bits != 8 + 7)
-        return complen + wraplen;
+        return (s->w_bits <= s->hash_bits && s->level ? fixedlen : storelen) +
+               wraplen;
 
-    /* default settings: return tight bound for that case */
+    /* default settings: return tight bound for that case -- ~0.03% overhead
+       plus a small constant */
     return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
            (sourceLen >> 25) + 13 - 6 + wraplen;
 }
@@ -713,10 +901,7 @@
  * IN assertion: the stream state is correct and there is enough room in
  * pending_buf.
  */
-local void putShortMSB (s, b)
-    deflate_state *s;
-    uInt b;
-{
+local void putShortMSB(deflate_state *s, uInt b) {
     put_byte(s, (Byte)(b >> 8));
     put_byte(s, (Byte)(b & 0xff));
 }
@@ -727,9 +912,7 @@
  * applications may wish to modify it to avoid allocating a large
  * strm->next_out buffer and copying into it. (See also read_buf()).
  */
-local void flush_pending(strm)
-    z_streamp strm;
-{
+local void flush_pending(z_streamp strm) {
     unsigned len;
     deflate_state *s = strm->state;
 
@@ -760,10 +943,7 @@
     } while (0)
 
 /* ========================================================================= */
-int ZEXPORT deflate (strm, flush)
-    z_streamp strm;
-    int flush;
-{
+int ZEXPORT deflate(z_streamp strm, int flush) {
     int old_flush; /* value of flush param for previous deflate call */
     deflate_state *s;
 
@@ -811,9 +991,11 @@
     }
 
     /* 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 header = (Z_DEFLATED + ((s->w_bits - 8) << 4)) << 8;
         uInt level_flags;
 
         if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2)
@@ -1073,9 +1255,7 @@
 }
 
 /* ========================================================================= */
-int ZEXPORT deflateEnd (strm)
-    z_streamp strm;
-{
+int ZEXPORT deflateEnd(z_streamp strm) {
     int status;
 
     if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
@@ -1099,16 +1279,14 @@
  * 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;
-{
+int ZEXPORT deflateCopy(z_streamp dest, z_streamp source) {
 #ifdef MAXSEG_64K
+    (void)dest;
+    (void)source;
     return Z_STREAM_ERROR;
 #else
     deflate_state *ds;
     deflate_state *ss;
-    ushf *overlay;
 
 
     if (deflateStateCheck(source) || dest == Z_NULL) {
@@ -1128,8 +1306,7 @@
     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, LIT_BUFS);
 
     if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
         ds->pending_buf == Z_NULL) {
@@ -1140,11 +1317,15 @@
     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);
+    zmemcpy(ds->pending_buf, ss->pending_buf, ds->lit_bufsize * LIT_BUFS);
 
     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;
+#ifdef LIT_MEM
+    ds->d_buf = (ushf *)(ds->pending_buf + (ds->lit_bufsize << 1));
+    ds->l_buf = ds->pending_buf + (ds->lit_bufsize << 2);
+#else
+    ds->sym_buf = ds->pending_buf + ds->lit_bufsize;
+#endif
 
     ds->l_desc.dyn_tree = ds->dyn_ltree;
     ds->d_desc.dyn_tree = ds->dyn_dtree;
@@ -1154,71 +1335,6 @@
 #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);
-    }
-#endif
-    strm->next_in  += len;
-    strm->total_in += len;
-
-    return len;
-}
-
-/* ===========================================================================
- * Initialize the "longest match" routines for a new zlib stream
- */
-local void lm_init (s)
-    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->insert = 0;
-    s->match_length = s->prev_length = MIN_MATCH-1;
-    s->match_available = 0;
-    s->ins_h = 0;
-#ifndef FASTEST
-#ifdef ASMV
-    match_init(); /* initialize the asm code */
-#endif
-#endif
-}
-
 #ifndef FASTEST
 /* ===========================================================================
  * Set match_start to the longest match starting at the given string and
@@ -1229,14 +1345,7 @@
  *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
  * OUT assertion: the match length is not greater than s->lookahead.
  */
-#ifndef ASMV
-/* For 80x86 and 680x0, an optimized version will be provided in match.asm or
- * match.S. The code will be functionally equivalent.
- */
-local uInt longest_match(s, cur_match)
-    deflate_state *s;
-    IPos cur_match;                             /* current match */
-{
+local uInt longest_match(deflate_state *s, IPos cur_match) {
     unsigned chain_length = s->max_chain_length;/* max hash chain length */
     register Bytef *scan = s->window + s->strstart; /* current string */
     register Bytef *match;                      /* matched string */
@@ -1257,10 +1366,10 @@
      */
     register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;
     register ush scan_start = *(ushf*)scan;
-    register ush scan_end   = *(ushf*)(scan+best_len-1);
+    register ush scan_end   = *(ushf*)(scan + best_len - 1);
 #else
     register Bytef *strend = s->window + s->strstart + MAX_MATCH;
-    register Byte scan_end1  = scan[best_len-1];
+    register Byte scan_end1  = scan[best_len - 1];
     register Byte scan_end   = scan[best_len];
 #endif
 
@@ -1278,7 +1387,8 @@
      */
     if ((uInt)nice_match > s->lookahead) nice_match = (int)s->lookahead;
 
-    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
+    Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
+           "need lookahead");
 
     do {
         Assert(cur_match < s->strstart, "no future");
@@ -1296,43 +1406,44 @@
         /* This code assumes sizeof(unsigned short) == 2. Do not use
          * UNALIGNED_OK if your compiler uses a different size.
          */
-        if (*(ushf*)(match+best_len-1) != scan_end ||
+        if (*(ushf*)(match + best_len - 1) != scan_end ||
             *(ushf*)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
+         * 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
+         * 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 (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
-                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
-                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
-                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&
+        } while (*(ushf*)(scan += 2) == *(ushf*)(match += 2) &&
+                 *(ushf*)(scan += 2) == *(ushf*)(match += 2) &&
+                 *(ushf*)(scan += 2) == *(ushf*)(match += 2) &&
+                 *(ushf*)(scan += 2) == *(ushf*)(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");
+        /* 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);
+        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;
+        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
+        /* 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
@@ -1342,7 +1453,7 @@
         Assert(*scan == *match, "match[2]?");
 
         /* We check for insufficient lookahead only every 8th comparison;
-         * the 256th check will be made at strstart+258.
+         * the 256th check will be made at strstart + 258.
          */
         do {
         } while (*++scan == *++match && *++scan == *++match &&
@@ -1351,7 +1462,8 @@
                  *++scan == *++match && *++scan == *++match &&
                  scan < strend);
 
-        Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+        Assert(scan <= s->window + (unsigned)(s->window_size - 1),
+               "wild scan");
 
         len = MAX_MATCH - (int)(strend - scan);
         scan = strend - MAX_MATCH;
@@ -1363,9 +1475,9 @@
             best_len = len;
             if (len >= nice_match) break;
 #ifdef UNALIGNED_OK
-            scan_end = *(ushf*)(scan+best_len-1);
+            scan_end = *(ushf*)(scan + best_len - 1);
 #else
-            scan_end1  = scan[best_len-1];
+            scan_end1  = scan[best_len - 1];
             scan_end   = scan[best_len];
 #endif
         }
@@ -1375,17 +1487,13 @@
     if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
     return s->lookahead;
 }
-#endif /* ASMV */
 
 #else /* FASTEST */
 
 /* ---------------------------------------------------------------------------
  * Optimized version for FASTEST only
  */
-local uInt longest_match(s, cur_match)
-    deflate_state *s;
-    IPos cur_match;                             /* current match */
-{
+local uInt longest_match(deflate_state *s, IPos cur_match) {
     register Bytef *scan = s->window + s->strstart; /* current string */
     register Bytef *match;                       /* matched string */
     register int len;                           /* length of current match */
@@ -1396,7 +1504,8 @@
      */
     Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");
 
-    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");
+    Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
+           "need lookahead");
 
     Assert(cur_match < s->strstart, "no future");
 
@@ -1406,7 +1515,7 @@
      */
     if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;
 
-    /* The check at best_len-1 can be removed because it will be made
+    /* 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
@@ -1416,7 +1525,7 @@
     Assert(*scan == *match, "match[2]?");
 
     /* We check for insufficient lookahead only every 8th comparison;
-     * the 256th check will be made at strstart+258.
+     * the 256th check will be made at strstart + 258.
      */
     do {
     } while (*++scan == *++match && *++scan == *++match &&
@@ -1425,7 +1534,7 @@
              *++scan == *++match && *++scan == *++match &&
              scan < strend);
 
-    Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");
+    Assert(scan <= s->window + (unsigned)(s->window_size - 1), "wild scan");
 
     len = MAX_MATCH - (int)(strend - scan);
 
@@ -1445,23 +1554,27 @@
 /* ===========================================================================
  * Check that the match at match_start is indeed a match.
  */
-local void check_match(s, start, match, length)
-    deflate_state *s;
-    IPos start, match;
-    int length;
-{
+local void check_match(deflate_state *s, IPos start, IPos match, int length) {
     /* check that the match is indeed a match */
-    if (zmemcmp(s->window + match,
-                s->window + start, length) != EQUAL) {
-        fprintf(stderr, " start %u, match %u, length %d\n",
-                start, match, length);
+    Bytef *back = s->window + (int)match, *here = s->window + start;
+    IPos len = length;
+    if (match == (IPos)-1) {
+        /* match starts one byte before the current window -- just compare the
+           subsequent length-1 bytes */
+        back++;
+        here++;
+        len--;
+    }
+    if (zmemcmp(back, here, len) != EQUAL) {
+        fprintf(stderr, " start %u, match %d, length %d\n",
+                start, (int)match, length);
         do {
-            fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
-        } while (--length != 0);
+            fprintf(stderr, "(%02x %02x)", *back++, *here++);
+        } while (--len != 0);
         z_error("invalid match");
     }
     if (z_verbose > 1) {
-        fprintf(stderr,"\\[%d,%d]", start-match, length);
+        fprintf(stderr,"\\[%d,%d]", start - match, length);
         do { putc(s->window[start++], stderr); } while (--length != 0);
     }
 }
@@ -1470,135 +1583,6 @@
 #endif /* ZLIB_DEBUG */
 
 /* ===========================================================================
- * 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).
- */
-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;
-            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;
-                str++;
-                s->insert--;
-                if (s->lookahead + s->insert < MIN_MATCH)
-                    break;
-            }
-        }
-        /* 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);
-
-    /* If the WIN_INIT bytes after the end of the current data have never been
-     * written, then zero those bytes in order to avoid memory check reports of
-     * the use of uninitialized (or uninitialised as Julian writes) bytes by
-     * the longest match routines.  Update the high water mark for the next
-     * time through here.  WIN_INIT is set to MAX_MATCH since the longest match
-     * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
-     */
-    if (s->high_water < s->window_size) {
-        ulg curr = s->strstart + (ulg)(s->lookahead);
-        ulg init;
-
-        if (s->high_water < curr) {
-            /* Previous high water mark below current data -- zero WIN_INIT
-             * bytes or up to end of window, whichever is less.
-             */
-            init = s->window_size - curr;
-            if (init > WIN_INIT)
-                init = WIN_INIT;
-            zmemzero(s->window + curr, (unsigned)init);
-            s->high_water = curr + init;
-        }
-        else if (s->high_water < (ulg)curr + WIN_INIT) {
-            /* High water mark at or above current data, but below current data
-             * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
-             * to end of window, whichever is less.
-             */
-            init = (ulg)curr + WIN_INIT - s->high_water;
-            if (init > s->window_size - s->high_water)
-                init = s->window_size - s->high_water;
-            zmemzero(s->window + s->high_water, (unsigned)init);
-            s->high_water += init;
-        }
-    }
-
-    Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
-           "not enough room for search");
-}
-
-/* ===========================================================================
  * Flush the current block, with given end-of-file flag.
  * IN assertion: strstart is set to the end of the current match.
  */
@@ -1638,12 +1622,9 @@
  *
  * deflate_stored() is written to minimize the number of times an input byte is
  * copied. It is most efficient with large input and output buffers, which
- * maximizes the opportunites to have a single copy from next_in to next_out.
+ * maximizes the opportunities to have a single copy from next_in to next_out.
  */
-local block_state deflate_stored(s, flush)
-    deflate_state *s;
-    int flush;
-{
+local block_state deflate_stored(deflate_state *s, int flush) {
     /* Smallest worthy block size when not flushing or finishing. By default
      * this is 32K. This can be as small as 507 bytes for memLevel == 1. For
      * large input and output buffers, the stored block size will be larger.
@@ -1742,6 +1723,7 @@
             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) {
@@ -1750,12 +1732,14 @@
                 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;
@@ -1770,7 +1754,7 @@
         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;
@@ -1779,12 +1763,15 @@
         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;
@@ -1821,10 +1808,7 @@
  * new strings in the dictionary only for unmatched strings or for short
  * matches. It is used only for the fast compression options.
  */
-local block_state deflate_fast(s, flush)
-    deflate_state *s;
-    int flush;
-{
+local block_state deflate_fast(deflate_state *s, int flush) {
     IPos hash_head;       /* head of the hash chain */
     int bflush;           /* set if current block must be flushed */
 
@@ -1842,7 +1826,7 @@
             if (s->lookahead == 0) break; /* flush the current block */
         }
 
-        /* Insert the string window[strstart .. strstart+2] in the
+        /* Insert the string window[strstart .. strstart + 2] in the
          * dictionary, and set hash_head to the head of the hash chain:
          */
         hash_head = NIL;
@@ -1890,7 +1874,7 @@
                 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]);
+                UPDATE_HASH(s, s->ins_h, s->window[s->strstart + 1]);
 #if MIN_MATCH != 3
                 Call UPDATE_HASH() MIN_MATCH-3 more times
 #endif
@@ -1901,7 +1885,7 @@
         } else {
             /* No match, output a literal byte */
             Tracevv((stderr,"%c", s->window[s->strstart]));
-            _tr_tally_lit (s, s->window[s->strstart], bflush);
+            _tr_tally_lit(s, s->window[s->strstart], bflush);
             s->lookahead--;
             s->strstart++;
         }
@@ -1912,7 +1896,7 @@
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
@@ -1923,10 +1907,7 @@
  * 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;
-{
+local block_state deflate_slow(deflate_state *s, int flush) {
     IPos hash_head;          /* head of hash chain */
     int bflush;              /* set if current block must be flushed */
 
@@ -1945,7 +1926,7 @@
             if (s->lookahead == 0) break; /* flush the current block */
         }
 
-        /* Insert the string window[strstart .. strstart+2] in the
+        /* Insert the string window[strstart .. strstart + 2] in the
          * dictionary, and set hash_head to the head of the hash chain:
          */
         hash_head = NIL;
@@ -1987,17 +1968,17 @@
             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);
+            check_match(s, s->strstart - 1, s->prev_match, s->prev_length);
 
-            _tr_tally_dist(s, s->strstart -1 - s->prev_match,
+            _tr_tally_dist(s, s->strstart - 1 - s->prev_match,
                            s->prev_length - MIN_MATCH, bflush);
 
             /* Insert in hash table all strings up to the end of the match.
-             * strstart-1 and strstart are already inserted. If there is not
+             * 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->lookahead -= s->prev_length - 1;
             s->prev_length -= 2;
             do {
                 if (++s->strstart <= max_insert) {
@@ -2015,8 +1996,8 @@
              * 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);
+            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);
             }
@@ -2034,8 +2015,8 @@
     }
     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);
+        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;
@@ -2043,7 +2024,7 @@
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
@@ -2054,10 +2035,7 @@
  * 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;
-{
+local block_state deflate_rle(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 */
@@ -2092,7 +2070,8 @@
                 if (s->match_length > s->lookahead)
                     s->match_length = s->lookahead;
             }
-            Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan");
+            Assert(scan <= s->window + (uInt)(s->window_size - 1),
+                   "wild scan");
         }
 
         /* Emit match if have run of MIN_MATCH or longer, else emit literal */
@@ -2107,7 +2086,7 @@
         } else {
             /* No match, output a literal byte */
             Tracevv((stderr,"%c", s->window[s->strstart]));
-            _tr_tally_lit (s, s->window[s->strstart], bflush);
+            _tr_tally_lit(s, s->window[s->strstart], bflush);
             s->lookahead--;
             s->strstart++;
         }
@@ -2118,7 +2097,7 @@
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }
@@ -2127,10 +2106,7 @@
  * 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;
-{
+local block_state deflate_huff(deflate_state *s, int flush) {
     int bflush;             /* set if current block must be flushed */
 
     for (;;) {
@@ -2147,7 +2123,7 @@
         /* Output a literal byte */
         s->match_length = 0;
         Tracevv((stderr,"%c", s->window[s->strstart]));
-        _tr_tally_lit (s, s->window[s->strstart], bflush);
+        _tr_tally_lit(s, s->window[s->strstart], bflush);
         s->lookahead--;
         s->strstart++;
         if (bflush) FLUSH_BLOCK(s, 0);
@@ -2157,7 +2133,7 @@
         FLUSH_BLOCK(s, 1);
         return finish_done;
     }
-    if (s->last_lit)
+    if (s->sym_next)
         FLUSH_BLOCK(s, 0);
     return block_done;
 }