src/larc.c

   1 /* ------------------------------------------------------------------------ */
   2 /* LHa for UNIX                                                                                                                         */
   3 /*                              larc.c -- extra *.lzs                                                                           */
   4 /*                                                                                                                                                      */
   5 /*              Modified                        Nobutaka Watazaki                                                       */
   6 /*                                                                                                                                                      */
   7 /*      Ver. 1.14       Source All chagned                              1995.01.14      N.Watazaki              */
   8 /* ------------------------------------------------------------------------ */
   9 #include "lha.h"
  10
  11 /* ------------------------------------------------------------------------ */
  12 static int      flag, flagcnt, matchpos;
  13 /* ------------------------------------------------------------------------ */
  14 unsigned short
  15 decode_c_lzs( /*void*/ )
  16 {
  17         if (getbits(1)) {
  18                 return getbits(8);
  19         }
  20         else {
  21                 matchpos = getbits(11);
  22                 return getbits(4) + 0x100;
  23         }
  24 }
  25
  26 /* ------------------------------------------------------------------------ */
  27 unsigned short
  28 decode_p_lzs( /*void*/ )
  29 {
  30         return (loc - matchpos - MAGIC0) & 0x7ff;
  31 }
  32
  33 /* ------------------------------------------------------------------------ */
  34 void
  35 decode_start_lzs( /*void*/ )
  36 {
  37         init_getbits();
  38     init_code_cache();
  39 }
  40
  41 /* ------------------------------------------------------------------------ */
  42 unsigned short
  43 decode_c_lz5( /*void*/ )
  44 {
  45         int             c;
  46
  47         if (flagcnt == 0) {
  48                 flagcnt = 8;
  49                 flag = getc(infile);
  50         }
  51         flagcnt--;
  52         c = getc(infile);
  53         if ((flag & 1) == 0) {
  54                 matchpos = c;
  55                 c = getc(infile);
  56                 matchpos += (c & 0xf0) << 4;
  57                 c &= 0x0f;
  58                 c += 0x100;
  59         }
  60         flag >>= 1;
  61         return c;
  62 }
  63
  64 /* ------------------------------------------------------------------------ */
  65 unsigned short
  66 decode_p_lz5( /*void*/ )
  67 {
  68         return (loc - matchpos - MAGIC5) & 0xfff;
  69 }
  70
  71 /* ------------------------------------------------------------------------ */
  72 void
  73 decode_start_lz5( /*void*/ )
  74 {
  75         int             i;
  76
  77         flagcnt = 0;
  78         for (i = 0; i < 256; i++)
  79                 memset(&text[i * 13 + 18], i, 13);
  80         for (i = 0; i < 256; i++)
  81                 text[256 * 13 + 18 + i] = i;
  82         for (i = 0; i < 256; i++)
  83                 text[256 * 13 + 256 + 18 + i] = 255 - i;
  84         memset(&text[256 * 13 + 512 + 18], 0, 128);
  85         memset(&text[256 * 13 + 512 + 128 + 18], ' ', 128 - 18);
  86 }
  87 /* Local Variables: */
  88 /* tab-width : 4 */
  89 /* End: */
  90 /* vi: set tabstop=4: */