1 /***********************************************************
2 maketbl.c -- make table for decoding
3 ***********************************************************/
7 make_table(struct huf_t *huf, int nchar, uchar bitlen[], int tablebits, ushort table[])
9 ushort count[17], weight[17], start[18], *p;
10 uint i, k, len, ch, jutbits, avail, nextcode, mask;
12 for (i = 1; i <= 16; i++)
14 for (i = 0; i < nchar; i++)
18 for (i = 1; i <= 16; i++)
19 start[i + 1] = start[i] + (count[i] << (16 - i));
20 if (start[17] != (ushort) (1U << 16))
23 jutbits = 16 - tablebits;
24 for (i = 1; i <= tablebits; i++) {
26 weight[i] = 1U << (tablebits - i);
29 weight[i] = 1U << (16 - i);
33 i = start[tablebits + 1] >> jutbits;
34 if (i != (ushort) (1U << 16)) {
41 mask = 1U << (15 - tablebits);
42 for (ch = 0; ch < nchar; ch++) {
43 if ((len = bitlen[ch]) == 0)
45 nextcode = start[len] + weight[len];
46 if (len <= tablebits) {
47 for (i = start[len]; i < nextcode; i++)
52 p = &table[k >> jutbits];
56 huf->right[avail] = huf->left[avail] = 0;
68 start[len] = nextcode;