]> git.lizzy.rs Git - zlib.git/blobdiff - inflate.c
Assure that the number of bits for deflatePrime() is valid.
[zlib.git] / inflate.c
index d3c718c066c84c56cad5a794ab7efde3b9287057..575fcdf82ad1060679ab144dc66b33a89d9001ef 100644 (file)
--- a/inflate.c
+++ b/inflate.c
@@ -1,5 +1,5 @@
 /* inflate.c -- zlib decompression
- * Copyright (C) 1995-2006 Mark Adler
+ * Copyright (C) 1995-2016 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -45,7 +45,7 @@
  * - Rearrange window copies in inflate_fast() for speed and simplification
  * - Unroll last copy for window match in inflate_fast()
  * - Use local copies of window variables in inflate_fast() for speed
- * - Pull out common write == 0 case for speed in inflate_fast()
+ * - Pull out common wnext == 0 case for speed in inflate_fast()
  * - Make op and len in inflate_fast() unsigned for consistency
  * - Add FAR to lcode and dcode declarations in inflate_fast()
  * - Simplified bad distance check in inflate_fast()
 #endif
 
 /* function prototypes */
+local int inflateStateCheck OF((z_streamp strm));
 local void fixedtables OF((struct inflate_state FAR *state));
-local int updatewindow OF((z_streamp strm, unsigned out));
+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, unsigned char FAR *buf,
+local unsigned syncsearch OF((unsigned FAR *have, const unsigned char FAR *buf,
                               unsigned len));
 
-int ZEXPORT inflateReset(strm)
+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 (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    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;
-    strm->adler = 1;        /* to support ill-conceived Java test suite */
+    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->dmax = 32768U;
     state->head = Z_NULL;
-    state->wsize = 0;
-    state->whave = 0;
-    state->write = 0;
     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 inflatePrime(strm, bits, value)
+int ZEXPORT inflateReset(strm)
 z_streamp strm;
-int bits;
-int value;
 {
     struct inflate_state FAR *state;
 
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
-    if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
-    value &= (1L << bits) - 1;
-    state->hold += value << state->bits;
-    state->bits += bits;
-    return Z_OK;
+    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;
+
+    /* extract wrap request from windowBits parameter */
+    if (windowBits < 0) {
+        wrap = 0;
+        windowBits = -windowBits;
+    }
+    else {
+        wrap = (windowBits >> 4) + 5;
+#ifdef GUNZIP
+        if (windowBits < 48)
+            windowBits &= 15;
+#endif
+    }
+
+    /* set number of window bits, free window if different */
+    if (windowBits && (windowBits < 8 || windowBits > 15))
+        return Z_STREAM_ERROR;
+    if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
+        ZFREE(strm, state->window);
+        state->window = Z_NULL;
+    }
+
+    /* update state and reset the rest of it */
+    state->wrap = wrap;
+    state->wbits = (unsigned)windowBits;
+    return inflateReset(strm);
 }
 
 int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
@@ -148,6 +198,7 @@ int windowBits;
 const char *version;
 int stream_size;
 {
+    int ret;
     struct inflate_state FAR *state;
 
     if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
@@ -156,33 +207,33 @@ int stream_size;
     if (strm == Z_NULL) return Z_STREAM_ERROR;
     strm->msg = Z_NULL;                 /* in case we return an error */
     if (strm->zalloc == (alloc_func)0) {
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
         strm->zalloc = zcalloc;
         strm->opaque = (voidpf)0;
+#endif
     }
-    if (strm->zfree == (free_func)0) strm->zfree = zcfree;
+    if (strm->zfree == (free_func)0)
+#ifdef Z_SOLO
+        return Z_STREAM_ERROR;
+#else
+        strm->zfree = zcfree;
+#endif
     state = (struct inflate_state FAR *)
             ZALLOC(strm, 1, sizeof(struct inflate_state));
     if (state == Z_NULL) return Z_MEM_ERROR;
     Tracev((stderr, "inflate: allocated\n"));
     strm->state = (struct internal_state FAR *)state;
-    if (windowBits < 0) {
-        state->wrap = 0;
-        windowBits = -windowBits;
-    }
-    else {
-        state->wrap = (windowBits >> 4) + 1;
-#ifdef GUNZIP
-        if (windowBits < 48) windowBits &= 15;
-#endif
-    }
-    if (windowBits < 8 || windowBits > 15) {
+    state->strm = strm;
+    state->window = Z_NULL;
+    state->mode = HEAD;     /* to pass state test in inflateReset2() */
+    ret = inflateReset2(strm, windowBits);
+    if (ret != Z_OK) {
         ZFREE(strm, state);
         strm->state = Z_NULL;
-        return Z_STREAM_ERROR;
     }
-    state->wbits = (unsigned)windowBits;
-    state->window = Z_NULL;
-    return inflateReset(strm);
+    return ret;
 }
 
 int ZEXPORT inflateInit_(strm, version, stream_size)
@@ -193,6 +244,27 @@ int stream_size;
     return inflateInit2_(strm, DEF_WBITS, version, stream_size);
 }
 
+int ZEXPORT inflatePrime(strm, bits, value)
+z_streamp strm;
+int bits;
+int value;
+{
+    struct inflate_state FAR *state;
+
+    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    if (bits < 0) {
+        state->hold = 0;
+        state->bits = 0;
+        return Z_OK;
+    }
+    if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR;
+    value &= (1L << bits) - 1;
+    state->hold += (unsigned)value << state->bits;
+    state->bits += (uInt)bits;
+    return Z_OK;
+}
+
 /*
    Return state with length and distance decoding tables and index sizes set to
    fixed code decoding.  Normally this returns fixed tables from inffixed.h.
@@ -287,8 +359,8 @@ void makefixed()
     low = 0;
     for (;;) {
         if ((low % 7) == 0) printf("\n        ");
-        printf("{%u,%u,%d}", state.lencode[low].op, state.lencode[low].bits,
-               state.lencode[low].val);
+        printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op,
+               state.lencode[low].bits, state.lencode[low].val);
         if (++low == size) break;
         putchar(',');
     }
@@ -321,12 +393,13 @@ void makefixed()
    output will fall in the output data, making match copies simpler and faster.
    The advantage may be dependent on the size of the processor's data caches.
  */
-local int updatewindow(strm, out)
+local int updatewindow(strm, end, copy)
 z_streamp strm;
-unsigned out;
+const Bytef *end;
+unsigned copy;
 {
     struct inflate_state FAR *state;
-    unsigned copy, dist;
+    unsigned dist;
 
     state = (struct inflate_state FAR *)strm->state;
 
@@ -341,30 +414,29 @@ unsigned out;
     /* if window not in use yet, initialize */
     if (state->wsize == 0) {
         state->wsize = 1U << state->wbits;
-        state->write = 0;
+        state->wnext = 0;
         state->whave = 0;
     }
 
     /* copy state->wsize or less output bytes into the circular window */
-    copy = out - strm->avail_out;
     if (copy >= state->wsize) {
-        zmemcpy(state->window, strm->next_out - state->wsize, state->wsize);
-        state->write = 0;
+        zmemcpy(state->window, end - state->wsize, state->wsize);
+        state->wnext = 0;
         state->whave = state->wsize;
     }
     else {
-        dist = state->wsize - state->write;
+        dist = state->wsize - state->wnext;
         if (dist > copy) dist = copy;
-        zmemcpy(state->window + state->write, strm->next_out - copy, dist);
+        zmemcpy(state->window + state->wnext, end - copy, dist);
         copy -= dist;
         if (copy) {
-            zmemcpy(state->window, strm->next_out - copy, copy);
-            state->write = copy;
+            zmemcpy(state->window, end - copy, copy);
+            state->wnext = copy;
             state->whave = state->wsize;
         }
         else {
-            state->write += dist;
-            if (state->write == state->wsize) state->write = 0;
+            state->wnext += dist;
+            if (state->wnext == state->wsize) state->wnext = 0;
             if (state->whave < state->wsize) state->whave += dist;
         }
     }
@@ -465,11 +537,6 @@ unsigned out;
         bits -= bits & 7; \
     } while (0)
 
-/* Reverse the bytes in a 32-bit value */
-#define REVERSE(q) \
-    ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
-     (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
-
 /*
    inflate() uses a state machine to process as much input data and generate as
    much output data as possible before returning.  The state machine is
@@ -557,7 +624,7 @@ z_streamp strm;
 int flush;
 {
     struct inflate_state FAR *state;
-    unsigned char FAR *next;    /* next input */
+    z_const unsigned char FAR *next;    /* next input */
     unsigned char FAR *put;     /* next output */
     unsigned have, left;        /* available input and output */
     unsigned long hold;         /* bit buffer */
@@ -575,7 +642,7 @@ int flush;
     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 (strm == Z_NULL || strm->state == Z_NULL || strm->next_out == Z_NULL ||
+    if (inflateStateCheck(strm) || strm->next_out == Z_NULL ||
         (strm->next_in == Z_NULL && strm->avail_in != 0))
         return Z_STREAM_ERROR;
 
@@ -595,6 +662,8 @@ int flush;
             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();
@@ -620,7 +689,9 @@ int flush;
             }
             DROPBITS(4);
             len = BITS(4) + 8;
-            if (len > state->wbits) {
+            if (state->wbits == 0)
+                state->wbits = len;
+            if (len > 15 || len > state->wbits) {
                 strm->msg = (char *)"invalid window size";
                 state->mode = BAD;
                 break;
@@ -647,14 +718,16 @@ int flush;
             }
             if (state->head != Z_NULL)
                 state->head->text = (int)((hold >> 8) & 1);
-            if (state->flags & 0x0200) CRC2(state->check, hold);
+            if ((state->flags & 0x0200) && (state->wrap & 4))
+                CRC2(state->check, hold);
             INITBITS();
             state->mode = TIME;
         case TIME:
             NEEDBITS(32);
             if (state->head != Z_NULL)
                 state->head->time = hold;
-            if (state->flags & 0x0200) CRC4(state->check, hold);
+            if ((state->flags & 0x0200) && (state->wrap & 4))
+                CRC4(state->check, hold);
             INITBITS();
             state->mode = OS;
         case OS:
@@ -663,7 +736,8 @@ int flush;
                 state->head->xflags = (int)(hold & 0xff);
                 state->head->os = (int)(hold >> 8);
             }
-            if (state->flags & 0x0200) CRC2(state->check, hold);
+            if ((state->flags & 0x0200) && (state->wrap & 4))
+                CRC2(state->check, hold);
             INITBITS();
             state->mode = EXLEN;
         case EXLEN:
@@ -672,7 +746,8 @@ int flush;
                 state->length = (unsigned)(hold);
                 if (state->head != Z_NULL)
                     state->head->extra_len = (unsigned)hold;
-                if (state->flags & 0x0200) CRC2(state->check, hold);
+                if ((state->flags & 0x0200) && (state->wrap & 4))
+                    CRC2(state->check, hold);
                 INITBITS();
             }
             else if (state->head != Z_NULL)
@@ -690,7 +765,7 @@ int flush;
                                 len + copy > state->head->extra_max ?
                                 state->head->extra_max - len : copy);
                     }
-                    if (state->flags & 0x0200)
+                    if ((state->flags & 0x0200) && (state->wrap & 4))
                         state->check = crc32(state->check, next, copy);
                     have -= copy;
                     next += copy;
@@ -709,9 +784,9 @@ int flush;
                     if (state->head != Z_NULL &&
                             state->head->name != Z_NULL &&
                             state->length < state->head->name_max)
-                        state->head->name[state->length++] = len;
+                        state->head->name[state->length++] = (Bytef)len;
                 } while (len && copy < have);
-                if (state->flags & 0x0200)
+                if ((state->flags & 0x0200) && (state->wrap & 4))
                     state->check = crc32(state->check, next, copy);
                 have -= copy;
                 next += copy;
@@ -730,9 +805,9 @@ int flush;
                     if (state->head != Z_NULL &&
                             state->head->comment != Z_NULL &&
                             state->length < state->head->comm_max)
-                        state->head->comment[state->length++] = len;
+                        state->head->comment[state->length++] = (Bytef)len;
                 } while (len && copy < have);
-                if (state->flags & 0x0200)
+                if ((state->flags & 0x0200) && (state->wrap & 4))
                     state->check = crc32(state->check, next, copy);
                 have -= copy;
                 next += copy;
@@ -744,7 +819,7 @@ int flush;
         case HCRC:
             if (state->flags & 0x0200) {
                 NEEDBITS(16);
-                if (hold != (state->check & 0xffff)) {
+                if ((state->wrap & 4) && hold != (state->check & 0xffff)) {
                     strm->msg = (char *)"header crc mismatch";
                     state->mode = BAD;
                     break;
@@ -761,7 +836,7 @@ int flush;
 #endif
         case DICTID:
             NEEDBITS(32);
-            strm->adler = state->check = REVERSE(hold);
+            strm->adler = state->check = ZSWAP32(hold);
             INITBITS();
             state->mode = DICT;
         case DICT:
@@ -772,7 +847,7 @@ int flush;
             strm->adler = state->check = adler32(0L, Z_NULL, 0);
             state->mode = TYPE;
         case TYPE:
-            if (flush == Z_BLOCK) goto inf_leave;
+            if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
         case TYPEDO:
             if (state->last) {
                 BYTEBITS();
@@ -792,7 +867,11 @@ int flush;
                 fixedtables(state);
                 Tracev((stderr, "inflate:     fixed codes block%s\n",
                         state->last ? " (last)" : ""));
-                state->mode = LEN;              /* decode codes */
+                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",
@@ -817,6 +896,9 @@ int flush;
             Tracev((stderr, "inflate:       stored length %u\n",
                     state->length));
             INITBITS();
+            state->mode = COPY_;
+            if (flush == Z_TREES) goto inf_leave;
+        case COPY_:
             state->mode = COPY;
         case COPY:
             copy = state->length;
@@ -862,7 +944,7 @@ int flush;
             while (state->have < 19)
                 state->lens[order[state->have++]] = 0;
             state->next = state->codes;
-            state->lencode = (code const FAR *)(state->next);
+            state->lencode = (const code FAR *)(state->next);
             state->lenbits = 7;
             ret = inflate_table(CODES, state->lens, 19, &(state->next),
                                 &(state->lenbits), state->work);
@@ -882,7 +964,6 @@ int flush;
                     PULLBYTE();
                 }
                 if (here.val < 16) {
-                    NEEDBITS(here.bits);
                     DROPBITS(here.bits);
                     state->lens[state->have++] = here.val;
                 }
@@ -926,9 +1007,18 @@ int flush;
             /* handle error breaks in while */
             if (state->mode == BAD) break;
 
-            /* build code tables */
+            /* 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 = (code const FAR *)(state->next);
+            state->lencode = (const code FAR *)(state->next);
             state->lenbits = 9;
             ret = inflate_table(LENS, state->lens, state->nlen, &(state->next),
                                 &(state->lenbits), state->work);
@@ -937,7 +1027,7 @@ int flush;
                 state->mode = BAD;
                 break;
             }
-            state->distcode = (code const FAR *)(state->next);
+            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);
@@ -947,14 +1037,20 @@ int flush;
                 break;
             }
             Tracev((stderr, "inflate:       codes ok\n"));
+            state->mode = LEN_;
+            if (flush == Z_TREES) goto inf_leave;
+        case LEN_:
             state->mode = LEN;
         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;
@@ -969,8 +1065,10 @@ int flush;
                     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 ?
@@ -981,6 +1079,7 @@ int flush;
             }
             if (here.op & 32) {
                 Tracevv((stderr, "inflate:         end of block\n"));
+                state->back = -1;
                 state->mode = TYPE;
                 break;
             }
@@ -996,8 +1095,10 @@ int flush;
                 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;
         case DIST:
             for (;;) {
@@ -1014,8 +1115,10 @@ int flush;
                     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;
@@ -1029,6 +1132,7 @@ int flush;
                 NEEDBITS(state->extra);
                 state->offset += BITS(state->extra);
                 DROPBITS(state->extra);
+                state->back += state->extra;
             }
 #ifdef INFLATE_STRICT
             if (state->offset > state->dmax) {
@@ -1064,12 +1168,12 @@ int flush;
                     break;
 #endif
                 }
-                if (copy > state->write) {
-                    copy -= state->write;
+                if (copy > state->wnext) {
+                    copy -= state->wnext;
                     from = state->window + (state->wsize - copy);
                 }
                 else
-                    from = state->window + (state->write - copy);
+                    from = state->window + (state->wnext - copy);
                 if (copy > state->length) copy = state->length;
             }
             else {                              /* copy from output */
@@ -1096,15 +1200,15 @@ int flush;
                 out -= left;
                 strm->total_out += out;
                 state->total += out;
-                if (out)
+                if ((state->wrap & 4) && out)
                     strm->adler = state->check =
                         UPDATE(state->check, put - out, out);
                 out = left;
-                if ((
+                if ((state->wrap & 4) && (
 #ifdef GUNZIP
                      state->flags ? hold :
 #endif
-                     REVERSE(hold)) != state->check) {
+                     ZSWAP32(hold)) != state->check) {
                     strm->msg = (char *)"incorrect data check";
                     state->mode = BAD;
                     break;
@@ -1148,8 +1252,9 @@ int flush;
      */
   inf_leave:
     RESTORE();
-    if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
-        if (updatewindow(strm, out)) {
+    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;
         }
@@ -1158,11 +1263,12 @@ int flush;
     strm->total_in += in;
     strm->total_out += out;
     state->total += out;
-    if (state->wrap && out)
+    if ((state->wrap & 4) && out)
         strm->adler = state->check =
             UPDATE(state->check, strm->next_out - out, out);
-    strm->data_type = state->bits + (state->last ? 64 : 0) +
-                      (state->mode == TYPE ? 128 : 0);
+    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;
@@ -1172,7 +1278,7 @@ int ZEXPORT inflateEnd(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
-    if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
+    if (inflateStateCheck(strm))
         return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     if (state->window != Z_NULL) ZFREE(strm, state->window);
@@ -1182,43 +1288,59 @@ z_streamp strm;
     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) {
+        zmemcpy(dictionary, state->window + state->wnext,
+                state->whave - state->wnext);
+        zmemcpy(dictionary + state->whave - state->wnext,
+                state->window, state->wnext);
+    }
+    if (dictLength != Z_NULL)
+        *dictLength = state->whave;
+    return Z_OK;
+}
+
 int ZEXPORT inflateSetDictionary(strm, dictionary, dictLength)
 z_streamp strm;
 const Bytef *dictionary;
 uInt dictLength;
 {
     struct inflate_state FAR *state;
-    unsigned long id;
+    unsigned long dictid;
+    int ret;
 
     /* check state */
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     if (state->wrap != 0 && state->mode != DICT)
         return Z_STREAM_ERROR;
 
-    /* check for correct dictionary id */
+    /* check for correct dictionary identifier */
     if (state->mode == DICT) {
-        id = adler32(0L, Z_NULL, 0);
-        id = adler32(id, dictionary, dictLength);
-        if (id != state->check)
+        dictid = adler32(0L, Z_NULL, 0);
+        dictid = adler32(dictid, dictionary, dictLength);
+        if (dictid != state->check)
             return Z_DATA_ERROR;
     }
 
-    /* copy dictionary to window */
-    if (updatewindow(strm, strm->avail_out)) {
+    /* copy dictionary to window using updatewindow(), which will amend the
+       existing dictionary if appropriate */
+    ret = updatewindow(strm, dictionary + dictLength, dictLength);
+    if (ret) {
         state->mode = MEM;
         return Z_MEM_ERROR;
     }
-    if (dictLength > state->wsize) {
-        zmemcpy(state->window, dictionary + dictLength - state->wsize,
-                state->wsize);
-        state->whave = state->wsize;
-    }
-    else {
-        zmemcpy(state->window + state->wsize - dictLength, dictionary,
-                dictLength);
-        state->whave = dictLength;
-    }
     state->havedict = 1;
     Tracev((stderr, "inflate:   dictionary set\n"));
     return Z_OK;
@@ -1231,7 +1353,7 @@ gz_headerp head;
     struct inflate_state FAR *state;
 
     /* check state */
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     if ((state->wrap & 2) == 0) return Z_STREAM_ERROR;
 
@@ -1254,7 +1376,7 @@ gz_headerp head;
  */
 local unsigned syncsearch(have, buf, len)
 unsigned FAR *have;
-unsigned char FAR *buf;
+const unsigned char FAR *buf;
 unsigned len;
 {
     unsigned got;
@@ -1284,7 +1406,7 @@ z_streamp strm;
     struct inflate_state FAR *state;
 
     /* check parameters */
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    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;
 
@@ -1311,6 +1433,8 @@ z_streamp strm;
 
     /* return no joy or set up to restart inflate() on a new block */
     if (state->have != 4) return Z_DATA_ERROR;
+    if (state->mode == HEAD)
+        state->wrap = 0;    /* never processed header, so assume raw */
     in = strm->total_in;  out = strm->total_out;
     inflateReset(strm);
     strm->total_in = in;  strm->total_out = out;
@@ -1331,7 +1455,7 @@ z_streamp strm;
 {
     struct inflate_state FAR *state;
 
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    if (inflateStateCheck(strm)) return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)strm->state;
     return state->mode == STORED && state->bits == 0;
 }
@@ -1346,8 +1470,7 @@ z_streamp source;
     unsigned wsize;
 
     /* check input */
-    if (dest == Z_NULL || source == Z_NULL || source->state == Z_NULL ||
-        source->zalloc == (alloc_func)0 || source->zfree == (free_func)0)
+    if (inflateStateCheck(source) || dest == Z_NULL)
         return Z_STREAM_ERROR;
     state = (struct inflate_state FAR *)source->state;
 
@@ -1366,8 +1489,9 @@ z_streamp source;
     }
 
     /* copy state */
-    zmemcpy(dest, source, sizeof(z_stream));
-    zmemcpy(copy, state, sizeof(struct inflate_state));
+    zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream));
+    zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state));
+    copy->strm = dest;
     if (state->lencode >= state->codes &&
         state->lencode <= state->codes + ENOUGH - 1) {
         copy->lencode = copy->codes + (state->lencode - state->codes);
@@ -1389,13 +1513,51 @@ int subvert;
 {
     struct inflate_state FAR *state;
 
-    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    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 && 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);
+}