contrib/blast/blast.c

44     int bitcnt;                 /* number of bits in bit buffer */
46     /* input limit error return state for bits() and decode() */
58  * Return need bits from the input stream.  This always leaves less than
59  * eight bits in the buffer.  bits() works properly for need == 0.
64  *   significant bit.  Therefore bits are dropped from the bottom of the bit
68 local int bits(struct state *s, int need)
72     /* load at least need bits into val */
79         val |= (int)(*(s->in)++) << s->bitcnt;          /* load eight bits */
84     /* drop need bits and update buffer, always zero to seven bits left */
88     /* return need bits, zeroing the bits above that */
108  * then -9 is returned after reading MAXBITS bits.
114  *   bits are pulled from the compressed data one at a time and used to
122  *   this ordering, the bits pulled during decoding are inverted to apply the
127     int len;            /* current number of bits in code */
128     int code;           /* len bits being decoded */
132     int bitbuf;         /* bits from stream */
133     int left;           /* bits left in next or left to process */
172  * count (high four bits + 1) and a code length (low four bits), generate the
183  * enough bits will resolve to a symbol.  If the return value is positive, then
246  *   byte is 4, 5, or 6 for the number of extra bits in the distance code.
258  * - If literals are uncoded, then the next eight bits are the literal, in the
260  *   no bit reversal is needed for either the length extra bits or the distance
261  *   extra bits.
282     int symbol;         /* decoded symbol, extra bits for distance */
308     static const char extra[16] = {     /* extra bits for length codes */
320     lit = bits(s, 8);
322     dict = bits(s, 8);
327         if (bits(s, 1)) {
330             len = base[symbol] + bits(s, extra[symbol]);
336             dist += bits(s, symbol);
366             symbol = lit ? decode(s, &litcode) : bits(s, 8);
397     /* return if bits() or decode() tries to read past available input */