Update zlib to 1.2.11

third_party/zlib/inftrees.c

 /* inftrees.c -- generate Huffman trees for efficient decoding
- * Copyright (C) 1995-2013 Mark Adler
+ * Copyright (C) 1995-2017 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #include "zutil.h"
 #include "inftrees.h"
 
 #define MAXBITS 15
 
 const char inflate_copyright[] =
-   " inflate 1.2.8 Copyright 1995-2013 Mark Adler ";
+   " inflate 1.2.11 Copyright 1995-2017 Mark Adler ";
 /*
   If you use the zlib library in a product, an acknowledgment is welcome
   in the documentation of your product. If for some reason you cannot
   include such an acknowledgment, I would appreciate that you keep this
   copyright string in the executable of your product.
  */
 
 /*
    Build a set of tables to decode the provided canonical Huffman code.
    The code lengths are lens[0..codes-1].  The result starts at *table,
@@ skipping 24 matching lines @@
     unsigned used;              /* code entries in table used */
     unsigned huff;              /* Huffman code */
     unsigned incr;              /* for incrementing code, index */
     unsigned fill;              /* index for replicating entries */
     unsigned low;               /* low bits for current root entry */
     unsigned mask;              /* mask for low root bits */
     code here;                  /* table entry for duplication */
     code FAR *next;             /* next available space in table */
     const unsigned short FAR *base;     /* base value table to use */
     const unsigned short FAR *extra;    /* extra bits table to use */
-    int end;                    /* use base and extra for symbol > end */
+    unsigned match;             /* use base and extra for symbol >= match */
     unsigned short count[MAXBITS+1];    /* number of codes of each length */
     unsigned short offs[MAXBITS+1];     /* offsets in table for each length */
     static const unsigned short lbase[31] = { /* Length codes 257..285 base */
         3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
         35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
     static const unsigned short lext[31] = { /* Length codes 257..285 extra */
         16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
-        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 72, 78};
+        19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 77, 202};
     static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
         1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
         257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
         8193, 12289, 16385, 24577, 0, 0};
     static const unsigned short dext[32] = { /* Distance codes 0..29 extra */
         16, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22,
         23, 23, 24, 24, 25, 25, 26, 26, 27, 27,
         28, 28, 29, 29, 64, 64};
 
     /*
@@ skipping 98 matching lines @@
        sym increments through all symbols, and the loop terminates when
        all codes of length max, i.e. all codes, have been processed.  This
        routine permits incomplete codes, so another loop after this one fills
        in the rest of the decoding tables with invalid code markers.
      */
 
     /* set up for code type */
     switch (type) {
     case CODES:
         base = extra = work;    /* dummy value--not used */
-        end = 19;
+        match = 20;
         break;
     case LENS:
         base = lbase;
-        base -= 257;
         extra = lext;
-        extra -= 257;
-        end = 256;
+        match = 257;
         break;
-    default:            /* DISTS */
+    default:    /* DISTS */
         base = dbase;
         extra = dext;
-        end = -1;
+        match = 0;
     }
 
     /* initialize state for loop */
     huff = 0;                   /* starting code */
     sym = 0;                    /* starting code symbol */
     len = min;                  /* starting code length */
     next = *table;              /* current table to fill in */
     curr = root;                /* current table index bits */
     drop = 0;                   /* current bits to drop from code for index */
     low = (unsigned)(-1);       /* trigger new sub-table when len > root */
     used = 1U << root;          /* use root table entries */
     mask = used - 1;            /* mask for comparing low */
 
     /* check available table space */
     if ((type == LENS && used > ENOUGH_LENS) ||
         (type == DISTS && used > ENOUGH_DISTS))
         return 1;
 
     /* process all codes and make table entries */
     for (;;) {
         /* create table entry */
         here.bits = (unsigned char)(len - drop);
-        if ((int)(work[sym]) < end) {
+        if (work[sym] + 1U < match) {
             here.op = (unsigned char)0;
             here.val = work[sym];
         }
-        else if ((int)(work[sym]) > end) {
-            here.op = (unsigned char)(extra[work[sym]]);
-            here.val = base[work[sym]];
+        else if (work[sym] >= match) {
+            here.op = (unsigned char)(extra[work[sym] - match]);
+            here.val = base[work[sym] - match];
         }
         else {
             here.op = (unsigned char)(32 + 64);         /* end of block */
             here.val = 0;
         }
 
         /* replicate for those indices with low len bits equal to huff */
         incr = 1U << (len - drop);
         fill = 1U << curr;
         min = fill;                 /* save offset to next table */
@@ skipping 61 matching lines @@
         here.bits = (unsigned char)(len - drop);
         here.val = (unsigned short)0;
         next[huff] = here;
     }
 
     /* set return parameters */
     *table += used;
     *bits = root;
     return 0;
 }