1 files changed, 39 insertions, 8 deletions
diff --git a/src/Common/zlib/inflate.c b/src/Common/zlib/inflate.c
index ac333e8c..7be8c636 100644
--- a/src/Common/zlib/inflate.c
+++ b/src/Common/zlib/inflate.c
@@ -1,37 +1,37 @@
 /* inflate.c -- zlib decompression
- * Copyright (C) 1995-2016 Mark Adler
+ * Copyright (C) 1995-2022 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 /*
  * Change history:
  *
  * 1.2.beta0    24 Nov 2002
  * - First version -- complete rewrite of inflate to simplify code, avoid
  *   creation of window when not needed, minimize use of window when it is
  *   needed, make inffast.c even faster, implement gzip decoding, and to
  *   improve code readability and style over the previous zlib inflate code
  *
  * 1.2.beta1    25 Nov 2002
  * - Use pointers for available input and output checking in inffast.c
  * - Remove input and output counters in inffast.c
  * - Change inffast.c entry and loop from avail_in >= 7 to >= 6
  * - Remove unnecessary second byte pull from length extra in inffast.c
  * - Unroll direct copy to three copies per loop in inffast.c
  *
  * 1.2.beta2    4 Dec 2002
  * - Change external routine names to reduce potential conflicts
  * - Correct filename to inffixed.h for fixed tables in inflate.c
  * - Make hbuf[] unsigned char to match parameter type in inflate.c
  * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset)
  *   to avoid negation problem on Alphas (64 bit) in inflate.c
  *
  * 1.2.beta3    22 Dec 2002
  * - Add comments on state->bits assertion in inffast.c
  * - Add comments on op field in inftrees.h
  * - Fix bug in reuse of allocated window after inflateReset()
  * - Remove bit fields--back to byte structure for speed
  * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths
  * - Change post-increments to pre-increments in inflate_fast(), PPC biased?
  * - Add compile time option, POSTINC, to use post-increments instead (Intel?)
  * - Make MATCH copy in inflate() much faster for when inflate_fast() not used
@@ -98,70 +98,71 @@ local int updatewindow OF((z_streamp strm, const unsigned char FAR *end,
                            unsigned copy));
 #ifdef BUILDFIXED
    void makefixed OF((void));
 #endif
 local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf,
                               unsigned len));
 
 local int inflateStateCheck(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
     if (strm == Z_NULL ||
         strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
         return 1;
     state = (struct inflate_state FAR *)strm->state;
     if (state == Z_NULL || state->strm != strm ||
         state->mode < HEAD || state->mode > SYNC)
         return 1;
     return 0;
 }
 
 int ZEXPORT inflateResetKeep(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     strm->total_in = strm->total_out = state->total = 0;
     strm->msg = Z_NULL;
     if (state->wrap)        /* to support ill-conceived Java test suite */
         strm->adler = state->wrap & 1;
     state->mode = HEAD;
     state->last = 0;
     state->havedict = 0;
+    state->flags = -1;
     state->dmax = 32768U;
     state->head = Z_NULL;
     state->hold = 0;
     state->bits = 0;
     state->lencode = state->distcode = state->next = state->codes;
     state->sane = 1;
     state->back = -1;
     Tracev((stderr, "inflate: reset\n"));
     return Z_OK;
 }
 
 int ZEXPORT inflateReset(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     state->wsize = 0;
     state->whave = 0;
     state->wnext = 0;
     return inflateResetKeep(strm);
 }
 
 int ZEXPORT inflateReset2(strm, windowBits)
 z_streamp strm;
 int windowBits;
 {
     int wrap;
     struct inflate_state FAR *state;
 
     /* get the state */
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
 
@@ -415,74 +416,74 @@ unsigned copy;
     if (state->wsize == 0) {
         state->wsize = 1U << state->wbits;
         state->wnext = 0;
         state->whave = 0;
     }
 
     /* copy state->wsize or less output bytes into the circular window */
     if (copy >= state->wsize) {
         zmemcpy(state->window, end - state->wsize, state->wsize);
         state->wnext = 0;
         state->whave = state->wsize;
     }
     else {
         dist = state->wsize - state->wnext;
         if (dist > copy) dist = copy;
         zmemcpy(state->window + state->wnext, end - copy, dist);
         copy -= dist;
         if (copy) {
             zmemcpy(state->window, end - copy, copy);
             state->wnext = copy;
             state->whave = state->wsize;
         }
         else {
             state->wnext += dist;
             if (state->wnext == state->wsize) state->wnext = 0;
             if (state->whave < state->wsize) state->whave += dist;
         }
     }
     return 0;
 }
 
 /* Macros for inflate(): */
 
 /* check function to use adler32() for zlib or crc32() for gzip */
 #ifdef GUNZIP
-#  define UPDATE(check, buf, len) \
+#  define UPDATE_CHECK(check, buf, len) \
     (state->flags ? crc32(check, buf, len) : adler32(check, buf, len))
 #else
-#  define UPDATE(check, buf, len) adler32(check, buf, len)
+#  define UPDATE_CHECK(check, buf, len) adler32(check, buf, len)
 #endif
 
 /* check macros for header crc */
 #ifdef GUNZIP
 #  define CRC2(check, word) \
     do { \
         hbuf[0] = (unsigned char)(word); \
         hbuf[1] = (unsigned char)((word) >> 8); \
         check = crc32(check, hbuf, 2); \
     } while (0)
 
 #  define CRC4(check, word) \
     do { \
         hbuf[0] = (unsigned char)(word); \
         hbuf[1] = (unsigned char)((word) >> 8); \
         hbuf[2] = (unsigned char)((word) >> 16); \
         hbuf[3] = (unsigned char)((word) >> 24); \
         check = crc32(check, hbuf, 4); \
     } while (0)
 #endif
 
 /* Load registers with state in inflate() for speed */
 #define LOAD() \
     do { \
         put = strm->next_out; \
         left = strm->avail_out; \
         next = strm->next_in; \
         have = strm->avail_in; \
         hold = state->hold; \
         bits = state->bits; \
     } while (0)
 
 /* Restore state from registers in inflate() */
 #define RESTORE() \
     do { \
@@ -638,356 +639,370 @@ int flush;
     int ret;                    /* return code */
 #ifdef GUNZIP
     unsigned char hbuf[4];      /* buffer for gzip header crc calculation */
 #endif
     static const unsigned short order[19] = /* permutation of code lengths */
         {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
 
     if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
         (strm->next_in == Z_NULL && strm->avail_in != 0))
         return Z_STREAM_ERROR;
 
     state = (struct inflate_state FAR *)strm->state;
     if (state->mode == TYPE) state->mode = TYPEDO;      /* skip check */
     LOAD();
     in = have;
     out = left;
     ret = Z_OK;
     for (;;)
         switch (state->mode) {
         case HEAD:
             if (state->wrap == 0) {
                 state->mode = TYPEDO;
                 break;
             }
             NEEDBITS(16);
 #ifdef GUNZIP
             if ((state->wrap & 2) && hold == 0x8b1f) {  /* gzip header */
                 if (state->wbits == 0)
                     state->wbits = 15;
                 state->check = crc32(0L, Z_NULL, 0);
                 CRC2(state->check, hold);
                 INITBITS();
                 state->mode = FLAGS;
                 break;
             }
-            state->flags = 0;           /* expect zlib header */
             if (state->head != Z_NULL)
                 state->head->done = -1;
             if (!(state->wrap & 1) ||   /* check if zlib header allowed */
 #else
             if (
 #endif
                 ((BITS(8) << 8) + (hold >> 8)) % 31) {
                 strm->msg = (char *)"incorrect header check";
                 state->mode = BAD;
                 break;
             }
             if (BITS(4) != Z_DEFLATED) {
                 strm->msg = (char *)"unknown compression method";
                 state->mode = BAD;
                 break;
             }
             DROPBITS(4);
             len = BITS(4) + 8;
             if (state->wbits == 0)
                 state->wbits = len;
             if (len > 15 || len > state->wbits) {
                 strm->msg = (char *)"invalid window size";
                 state->mode = BAD;
                 break;
             }
             state->dmax = 1U << len;
+            state->flags = 0;               /* indicate zlib header */
             Tracev((stderr, "inflate:   zlib header ok\n"));
             strm->adler = state->check = adler32(0L, Z_NULL, 0);
             state->mode = hold & 0x200 ? DICTID : TYPE;
             INITBITS();
             break;
 #ifdef GUNZIP
         case FLAGS:
             NEEDBITS(16);
             state->flags = (int)(hold);
             if ((state->flags & 0xff) != Z_DEFLATED) {
                 strm->msg = (char *)"unknown compression method";
                 state->mode = BAD;
                 break;
             }
             if (state->flags & 0xe000) {
                 strm->msg = (char *)"unknown header flags set";
                 state->mode = BAD;
                 break;
             }
             if (state->head != Z_NULL)
                 state->head->text = (int)((hold >> 8) & 1);
             if ((state->flags & 0x0200) && (state->wrap & 4))
                 CRC2(state->check, hold);
             INITBITS();
             state->mode = TIME;
+                /* fallthrough */
         case TIME:
             NEEDBITS(32);
             if (state->head != Z_NULL)
                 state->head->time = hold;
             if ((state->flags & 0x0200) && (state->wrap & 4))
                 CRC4(state->check, hold);
             INITBITS();
             state->mode = OS;
+                /* fallthrough */
         case OS:
             NEEDBITS(16);
             if (state->head != Z_NULL) {
                 state->head->xflags = (int)(hold & 0xff);
                 state->head->os = (int)(hold >> 8);
             }
             if ((state->flags & 0x0200) && (state->wrap & 4))
                 CRC2(state->check, hold);
             INITBITS();
             state->mode = EXLEN;
+                /* fallthrough */
         case EXLEN:
             if (state->flags & 0x0400) {
                 NEEDBITS(16);
                 state->length = (unsigned)(hold);
                 if (state->head != Z_NULL)
                     state->head->extra_len = (unsigned)hold;
                 if ((state->flags & 0x0200) && (state->wrap & 4))
                     CRC2(state->check, hold);
                 INITBITS();
             }
             else if (state->head != Z_NULL)
                 state->head->extra = Z_NULL;
             state->mode = EXTRA;
+                /* fallthrough */
         case EXTRA:
             if (state->flags & 0x0400) {
                 copy = state->length;
                 if (copy > have) copy = have;
                 if (copy) {
                     if (state->head != Z_NULL &&
                         state->head->extra != Z_NULL) {
                         len = state->head->extra_len - state->length;
                         zmemcpy(state->head->extra + len, next,
                                 len + copy > state->head->extra_max ?
                                 state->head->extra_max - len : copy);
                     }
                     if ((state->flags & 0x0200) && (state->wrap & 4))
                         state->check = crc32(state->check, next, copy);
                     have -= copy;
                     next += copy;
                     state->length -= copy;
                 }
                 if (state->length) goto inf_leave;
             }
             state->length = 0;
             state->mode = NAME;
+                /* fallthrough */
         case NAME:
             if (state->flags & 0x0800) {
                 if (have == 0) goto inf_leave;
                 copy = 0;
                 do {
                     len = (unsigned)(next[copy++]);
                     if (state->head != Z_NULL &&
                             state->head->name != Z_NULL &&
                             state->length < state->head->name_max)
                         state->head->name[state->length++] = (Bytef)len;
                 } while (len && copy < have);
                 if ((state->flags & 0x0200) && (state->wrap & 4))
                     state->check = crc32(state->check, next, copy);
                 have -= copy;
                 next += copy;
                 if (len) goto inf_leave;
             }
             else if (state->head != Z_NULL)
                 state->head->name = Z_NULL;
             state->length = 0;
             state->mode = COMMENT;
+                /* fallthrough */
         case COMMENT:
             if (state->flags & 0x1000) {
                 if (have == 0) goto inf_leave;
                 copy = 0;
                 do {
                     len = (unsigned)(next[copy++]);
                     if (state->head != Z_NULL &&
                             state->head->comment != Z_NULL &&
                             state->length < state->head->comm_max)
                         state->head->comment[state->length++] = (Bytef)len;
                 } while (len && copy < have);
                 if ((state->flags & 0x0200) && (state->wrap & 4))
                     state->check = crc32(state->check, next, copy);
                 have -= copy;
                 next += copy;
                 if (len) goto inf_leave;
             }
             else if (state->head != Z_NULL)
                 state->head->comment = Z_NULL;
             state->mode = HCRC;
+                /* fallthrough */
         case HCRC:
             if (state->flags & 0x0200) {
                 NEEDBITS(16);
                 if ((state->wrap & 4) && hold != (state->check & 0xffff)) {
                     strm->msg = (char *)"header crc mismatch";
                     state->mode = BAD;
                     break;
                 }
                 INITBITS();
             }
             if (state->head != Z_NULL) {
                 state->head->hcrc = (int)((state->flags >> 9) & 1);
                 state->head->done = 1;
             }
             strm->adler = state->check = crc32(0L, Z_NULL, 0);
             state->mode = TYPE;
             break;
 #endif
         case DICTID:
             NEEDBITS(32);
             strm->adler = state->check = ZSWAP32(hold);
             INITBITS();
             state->mode = DICT;
+                /* fallthrough */
         case DICT:
             if (state->havedict == 0) {
                 RESTORE();
                 return Z_NEED_DICT;
             }
             strm->adler = state->check = adler32(0L, Z_NULL, 0);
             state->mode = TYPE;
+                /* fallthrough */
         case TYPE:
             if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
+                /* fallthrough */
         case TYPEDO:
             if (state->last) {
                 BYTEBITS();
                 state->mode = CHECK;
                 break;
             }
             NEEDBITS(3);
             state->last = BITS(1);
             DROPBITS(1);
             switch (BITS(2)) {
             case 0:                             /* stored block */
                 Tracev((stderr, "inflate:     stored block%s\n",
                         state->last ? " (last)" : ""));
                 state->mode = STORED;
                 break;
             case 1:                             /* fixed block */
                 fixedtables(state);
                 Tracev((stderr, "inflate:     fixed codes block%s\n",
                         state->last ? " (last)" : ""));
                 state->mode = LEN_;             /* decode codes */
                 if (flush == Z_TREES) {
                     DROPBITS(2);
                     goto inf_leave;
                 }
                 break;
             case 2:                             /* dynamic block */
                 Tracev((stderr, "inflate:     dynamic codes block%s\n",
                         state->last ? " (last)" : ""));
                 state->mode = TABLE;
                 break;
             case 3:
                 strm->msg = (char *)"invalid block type";
                 state->mode = BAD;
             }
             DROPBITS(2);
             break;
         case STORED:
             BYTEBITS();                         /* go to byte boundary */
             NEEDBITS(32);
             if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
                 strm->msg = (char *)"invalid stored block lengths";
                 state->mode = BAD;
                 break;
             }
             state->length = (unsigned)hold & 0xffff;
             Tracev((stderr, "inflate:       stored length %u\n",
                     state->length));
             INITBITS();
             state->mode = COPY_;
             if (flush == Z_TREES) goto inf_leave;
+                /* fallthrough */
         case COPY_:
             state->mode = COPY;
+                /* fallthrough */
         case COPY:
             copy = state->length;
             if (copy) {
                 if (copy > have) copy = have;
                 if (copy > left) copy = left;
                 if (copy == 0) goto inf_leave;
                 zmemcpy(put, next, copy);
                 have -= copy;
                 next += copy;
                 left -= copy;
                 put += copy;
                 state->length -= copy;
                 break;
             }
             Tracev((stderr, "inflate:       stored end\n"));
             state->mode = TYPE;
             break;
         case TABLE:
             NEEDBITS(14);
             state->nlen = BITS(5) + 257;
             DROPBITS(5);
             state->ndist = BITS(5) + 1;
             DROPBITS(5);
             state->ncode = BITS(4) + 4;
             DROPBITS(4);
 #ifndef PKZIP_BUG_WORKAROUND
             if (state->nlen > 286 || state->ndist > 30) {
                 strm->msg = (char *)"too many length or distance symbols";
                 state->mode = BAD;
                 break;
             }
 #endif
             Tracev((stderr, "inflate:       table sizes ok\n"));
             state->have = 0;
             state->mode = LENLENS;
+                /* fallthrough */
         case LENLENS:
             while (state->have < state->ncode) {
                 NEEDBITS(3);
                 state->lens[order[state->have++]] = (unsigned short)BITS(3);
                 DROPBITS(3);
             }
             while (state->have < 19)
                 state->lens[order[state->have++]] = 0;
             state->next = state->codes;
             state->lencode = (const code FAR *)(state->next);
             state->lenbits = 7;
             ret = inflate_table(CODES, state->lens, 19, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
                 strm->msg = (char *)"invalid code lengths set";
                 state->mode = BAD;
                 break;
             }
             Tracev((stderr, "inflate:       code lengths ok\n"));
             state->have = 0;
             state->mode = CODELENS;
+                /* fallthrough */
         case CODELENS:
             while (state->have < state->nlen + state->ndist) {
                 for (;;) {
                     here = state->lencode[BITS(state->lenbits)];
                     if ((unsigned)(here.bits) <= bits) break;
                     PULLBYTE();
                 }
                 if (here.val < 16) {
                     DROPBITS(here.bits);
                     state->lens[state->have++] = here.val;
                 }
                 else {
                     if (here.val == 16) {
                         NEEDBITS(here.bits + 2);
                         DROPBITS(here.bits);
                         if (state->have == 0) {
                             strm->msg = (char *)"invalid bit length repeat";
                             state->mode = BAD;
                             break;
                         }
                         len = state->lens[state->have - 1];
                         copy = 3 + BITS(2);
                         DROPBITS(2);
                     }
                     else if (here.val == 17) {
                         NEEDBITS(here.bits + 3);
                         DROPBITS(here.bits);
                         len = 0;
                         copy = 3 + BITS(3);
                         DROPBITS(3);
                     }
                     else {
                         NEEDBITS(here.bits + 7);
                         DROPBITS(here.bits);
                         len = 0;
@@ -1007,297 +1022,306 @@ int flush;
             /* handle error breaks in while */
             if (state->mode == BAD) break;
 
             /* check for end-of-block code (better have one) */
             if (state->lens[256] == 0) {
                 strm->msg = (char *)"invalid code -- missing end-of-block";
                 state->mode = BAD;
                 break;
             }
 
             /* build code tables -- note: do not change the lenbits or distbits
                values here (9 and 6) without reading the comments in inftrees.h
                concerning the ENOUGH constants, which depend on those values */
             state->next = state->codes;
             state->lencode = (const code FAR *)(state->next);
             state->lenbits = 9;
             ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
                                 &(state->lenbits), state->work);
             if (ret) {
                 strm->msg = (char *)"invalid literal/lengths set";
                 state->mode = BAD;
                 break;
             }
             state->distcode = (const code FAR *)(state->next);
             state->distbits = 6;
             ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist,
                             &(state->next), &(state->distbits), state->work);
             if (ret) {
                 strm->msg = (char *)"invalid distances set";
                 state->mode = BAD;
                 break;
             }
             Tracev((stderr, "inflate:       codes ok\n"));
             state->mode = LEN_;
             if (flush == Z_TREES) goto inf_leave;
+                /* fallthrough */
         case LEN_:
             state->mode = LEN;
+                /* fallthrough */
         case LEN:
             if (have >= 6 && left >= 258) {
                 RESTORE();
                 inflate_fast(strm, out);
                 LOAD();
                 if (state->mode == TYPE)
                     state->back = -1;
                 break;
             }
             state->back = 0;
             for (;;) {
                 here = state->lencode[BITS(state->lenbits)];
                 if ((unsigned)(here.bits) <= bits) break;
                 PULLBYTE();
             }
             if (here.op && (here.op & 0xf0) == 0) {
                 last = here;
                 for (;;) {
                     here = state->lencode[last.val +
                             (BITS(last.bits + last.op) >> last.bits)];
                     if ((unsigned)(last.bits + here.bits) <= bits) break;
                     PULLBYTE();
                 }
                 DROPBITS(last.bits);
                 state->back += last.bits;
             }
             DROPBITS(here.bits);
             state->back += here.bits;
             state->length = (unsigned)here.val;
             if ((int)(here.op) == 0) {
                 Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
                         "inflate:         literal '%c'\n" :
                         "inflate:         literal 0x%02x\n", here.val));
                 state->mode = LIT;
                 break;
             }
             if (here.op & 32) {
                 Tracevv((stderr, "inflate:         end of block\n"));
                 state->back = -1;
                 state->mode = TYPE;
                 break;
             }
             if (here.op & 64) {
                 strm->msg = (char *)"invalid literal/length code";
                 state->mode = BAD;
                 break;
             }
             state->extra = (unsigned)(here.op) & 15;
             state->mode = LENEXT;
+                /* fallthrough */
         case LENEXT:
             if (state->extra) {
                 NEEDBITS(state->extra);
                 state->length += BITS(state->extra);
                 DROPBITS(state->extra);
                 state->back += state->extra;
             }
             Tracevv((stderr, "inflate:         length %u\n", state->length));
             state->was = state->length;
             state->mode = DIST;
+                /* fallthrough */
         case DIST:
             for (;;) {
                 here = state->distcode[BITS(state->distbits)];
                 if ((unsigned)(here.bits) <= bits) break;
                 PULLBYTE();
             }
             if ((here.op & 0xf0) == 0) {
                 last = here;
                 for (;;) {
                     here = state->distcode[last.val +
                             (BITS(last.bits + last.op) >> last.bits)];
                     if ((unsigned)(last.bits + here.bits) <= bits) break;
                     PULLBYTE();
                 }
                 DROPBITS(last.bits);
                 state->back += last.bits;
             }
             DROPBITS(here.bits);
             state->back += here.bits;
             if (here.op & 64) {
                 strm->msg = (char *)"invalid distance code";
                 state->mode = BAD;
                 break;
             }
             state->offset = (unsigned)here.val;
             state->extra = (unsigned)(here.op) & 15;
             state->mode = DISTEXT;
+                /* fallthrough */
         case DISTEXT:
             if (state->extra) {
                 NEEDBITS(state->extra);
                 state->offset += BITS(state->extra);
                 DROPBITS(state->extra);
                 state->back += state->extra;
             }
 #ifdef INFLATE_STRICT
             if (state->offset > state->dmax) {
                 strm->msg = (char *)"invalid distance too far back";
                 state->mode = BAD;
                 break;
             }
 #endif
             Tracevv((stderr, "inflate:         distance %u\n", state->offset));
             state->mode = MATCH;
+                /* fallthrough */
         case MATCH:
             if (left == 0) goto inf_leave;
             copy = out - left;
             if (state->offset > copy) {         /* copy from window */
                 copy = state->offset - copy;
                 if (copy > state->whave) {
                     if (state->sane) {
                         strm->msg = (char *)"invalid distance too far back";
                         state->mode = BAD;
                         break;
                     }
 #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
                     Trace((stderr, "inflate.c too far\n"));
                     copy -= state->whave;
                     if (copy > state->length) copy = state->length;
                     if (copy > left) copy = left;
                     left -= copy;
                     state->length -= copy;
                     do {
                         *put++ = 0;
                     } while (--copy);
                     if (state->length == 0) state->mode = LEN;
                     break;
 #endif
                 }
                 if (copy > state->wnext) {
                     copy -= state->wnext;
                     from = state->window + (state->wsize - copy);
                 }
                 else
                     from = state->window + (state->wnext - copy);
                 if (copy > state->length) copy = state->length;
             }
             else {                              /* copy from output */
                 from = put - state->offset;
                 copy = state->length;
             }
             if (copy > left) copy = left;
             left -= copy;
             state->length -= copy;
             do {
                 *put++ = *from++;
             } while (--copy);
             if (state->length == 0) state->mode = LEN;
             break;
         case LIT:
             if (left == 0) goto inf_leave;
             *put++ = (unsigned char)(state->length);
             left--;
             state->mode = LEN;
             break;
         case CHECK:
             if (state->wrap) {
                 NEEDBITS(32);
                 out -= left;
                 strm->total_out += out;
                 state->total += out;
                 if ((state->wrap & 4) && out)
                     strm->adler = state->check =
-                        UPDATE(state->check, put - out, out);
+                        UPDATE_CHECK(state->check, put - out, out);
                 out = left;
                 if ((state->wrap & 4) && (
 #ifdef GUNZIP
                      state->flags ? hold :
 #endif
                      ZSWAP32(hold)) != state->check) {
                     strm->msg = (char *)"incorrect data check";
                     state->mode = BAD;
                     break;
                 }
                 INITBITS();
                 Tracev((stderr, "inflate:   check matches trailer\n"));
             }
 #ifdef GUNZIP
             state->mode = LENGTH;
+                /* fallthrough */
         case LENGTH:
             if (state->wrap && state->flags) {
                 NEEDBITS(32);
-                if (hold != (state->total & 0xffffffffUL)) {
+                if ((state->wrap & 4) && hold != (state->total & 0xffffffff)) {
                     strm->msg = (char *)"incorrect length check";
                     state->mode = BAD;
                     break;
                 }
                 INITBITS();
                 Tracev((stderr, "inflate:   length matches trailer\n"));
             }
 #endif
             state->mode = DONE;
+                /* fallthrough */
         case DONE:
             ret = Z_STREAM_END;
             goto inf_leave;
         case BAD:
             ret = Z_DATA_ERROR;
             goto inf_leave;
         case MEM:
             return Z_MEM_ERROR;
         case SYNC:
+                /* fallthrough */
         default:
             return Z_STREAM_ERROR;
         }
 
     /*
        Return from inflate(), updating the total counts and the check value.
        If there was no progress during the inflate() call, return a buffer
        error.  Call updatewindow() to create and/or update the window state.
        Note: a memory error from inflate() is non-recoverable.
      */
   inf_leave:
     RESTORE();
     if (state->wsize || (out != strm->avail_out && state->mode < BAD &&
             (state->mode < CHECK || flush != Z_FINISH)))
         if (updatewindow(strm, strm->next_out, out - strm->avail_out)) {
             state->mode = MEM;
             return Z_MEM_ERROR;
         }
     in -= strm->avail_in;
     out -= strm->avail_out;
     strm->total_in += in;
     strm->total_out += out;
     state->total += out;
     if ((state->wrap & 4) && out)
         strm->adler = state->check =
-            UPDATE(state->check, strm->next_out - out, out);
+            UPDATE_CHECK(state->check, strm->next_out - out, out);
     strm->data_type = (int)state->bits + (state->last ? 64 : 0) +
                       (state->mode == TYPE ? 128 : 0) +
                       (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
     if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
         ret = Z_BUF_ERROR;
     return ret;
 }
 
 int ZEXPORT inflateEnd(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
     if (inflateStateCheck(strm))
         return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     if (state->window != Z_NULL) ZFREE(strm, state->window);
     ZFREE(strm, strm->state);
     strm->state = Z_NULL;
     Tracev((stderr, "inflate: end\n"));
     return Z_OK;
 }
 
 int ZEXPORT inflateGetDictionary(strm, dictionary, dictLength)
 z_streamp strm;
 Bytef *dictionary;
 uInt *dictLength;
 {
     struct inflate_state FAR *state;
 
     /* check state */
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
 
     /* copy dictionary */
     if (state->whave && dictionary != Z_NULL) {
@@ -1369,105 +1393,112 @@ gz_headerp head;
    found in order so far, in 0..3.  On return *have is updated to the new
    state.  If on return *have equals four, then the pattern was found and the
    return value is how many bytes were read including the last byte of the
    pattern.  If *have is less than four, then the pattern has not been found
    yet and the return value is len.  In the latter case, syncsearch() can be
    called again with more data and the *have state.  *have is initialized to
    zero for the first call.
  */
 local unsigned syncsearch(have, buf, len)
 unsigned FAR *have;
 const unsigned char FAR *buf;
 unsigned len;
 {
     unsigned got;
     unsigned next;
 
     got = *have;
     next = 0;
     while (next < len && got < 4) {
         if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
             got++;
         else if (buf[next])
             got = 0;
         else
             got = 4 - got;
         next++;
     }
     *have = got;
     return next;
 }
 
 int ZEXPORT inflateSync(strm)
 z_streamp strm;
 {
     unsigned len;               /* number of bytes to look at or looked at */
+    int flags;                  /* temporary to save header status */
     unsigned long in, out;      /* temporary to save total_in and total_out */
     unsigned char buf[4];       /* to restore bit buffer to byte string */
     struct inflate_state FAR *state;
 
     /* check parameters */
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
 
     /* if first time, start search in bit buffer */
     if (state->mode != SYNC) {
         state->mode = SYNC;
         state->hold <<= state->bits & 7;
         state->bits -= state->bits & 7;
         len = 0;
         while (state->bits >= 8) {
             buf[len++] = (unsigned char)(state->hold);
             state->hold >>= 8;
             state->bits -= 8;
         }
         state->have = 0;
         syncsearch(&(state->have), buf, len);
     }
 
     /* search available input */
     len = syncsearch(&(state->have), strm->next_in, strm->avail_in);
     strm->avail_in -= len;
     strm->next_in += len;
     strm->total_in += len;
 
     /* return no joy or set up to restart inflate() on a new block */
     if (state->have != 4) return Z_DATA_ERROR;
+    if (state->flags == -1)
+        state->wrap = 0;    /* if no header yet, treat as raw */
+    else
+        state->wrap &= ~4;  /* no point in computing a check value now */
+    flags = state->flags;
     in = strm->total_in;  out = strm->total_out;
     inflateReset(strm);
     strm->total_in = in;  strm->total_out = out;
+    state->flags = flags;
     state->mode = TYPE;
     return Z_OK;
 }
 
 /*
    Returns true if inflate is currently at the end of a block generated by
    Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
    implementation to provide an additional safety check. PPP uses
    Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
    block. When decompressing, PPP checks that at the end of input packet,
    inflate is waiting for these length bytes.
  */
 int ZEXPORT inflateSyncPoint(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     return state->mode == STORED && state->bits == 0;
 }
 
 int ZEXPORT inflateCopy(dest, source)
 z_streamp dest;
 z_streamp source;
 {
     struct inflate_state FAR *state;
     struct inflate_state FAR *copy;
     unsigned char FAR *window;
     unsigned wsize;
 
     /* check input */
     if (inflateStateCheck(source) || dest == Z_NULL)
         return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)source->state;
@@ -1499,63 +1530,63 @@ z_streamp source;
     if (window != Z_NULL) {
         wsize = 1U << state->wbits;
         zmemcpy(window, state->window, wsize);
     }
     copy->window = window;
     dest->state = (struct internal_state FAR *)copy;
     return Z_OK;
 }
 
 int ZEXPORT inflateUndermine(strm, subvert)
 z_streamp strm;
 int subvert;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
 #ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
     state->sane = !subvert;
     return Z_OK;
 #else
     (void)subvert;
     state->sane = 1;
     return Z_DATA_ERROR;
 #endif
 }
 
 int ZEXPORT inflateValidate(strm, check)
 z_streamp strm;
 int check;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
-    if (check)
+    if (check && state->wrap)
         state->wrap |= 4;
     else
         state->wrap &= ~4;
     return Z_OK;
 }
 
 long ZEXPORT inflateMark(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
 
     if (inflateStateCheck(strm))
         return -(1L << 16);
     state = (struct inflate_state FAR *)strm->state;
     return (long)(((unsigned long)((long)state->back)) << 16) +
         (state->mode == COPY ? state->length :
             (state->mode == MATCH ? state->was - state->length : 0));
 }
 
 unsigned long ZEXPORT inflateCodesUsed(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
     if (inflateStateCheck(strm)) return (unsigned long)-1;
     state = (struct inflate_state FAR *)strm->state;
     return (unsigned long)(state->next - state->codes);
 }