1: #include "../h/rt.h"
   2: 
   3: /*
   4:  * x ++ y - union of csets x and y or of sets x and y.
   5:  */
   6: 
   7: unioncs(nargs, arg2, arg1, arg0)
   8: int nargs;
   9: struct descrip arg2, arg1, arg0;
  10:    {
  11:    DclSave
  12:    register int i;
  13:    union block *bp;
  14:    int *cs1, *cs2, csbuf1[CSETSIZE], csbuf2[CSETSIZE];
  15:    extern struct b_cset *alccset();
  16: #ifdef SETS
  17:    int res;
  18:    struct b_set *srcp, *tstp, *dstp;
  19:    struct b_selem *ep;
  20:    struct descrip *dp, *hook;
  21:    extern struct b_set *alcset();
  22:    extern struct b_selem *alcselem();
  23:    extern struct descrip *memb();
  24: #endif SETS
  25: 
  26:    SetBound;
  27: #ifdef SETS
  28:    DeRef(arg1)
  29:    DeRef(arg2)
  30:    if (QUAL(arg1) || QUAL(arg2))
  31:       goto skipsets;
  32:    if (TYPE(arg1) == T_SET && TYPE(arg2) != T_SET)
  33:       runerr(119,&arg2);
  34:    if (TYPE(arg2) == T_SET && TYPE(arg1) != T_SET)
  35:       runerr(119,&arg1);
  36:    if (TYPE(arg1) == T_SET && TYPE(arg2) == T_SET) {
  37:       /*
  38:        *  Both x and y are sets - do set union
  39:        *  get enough space for a set as big as x + y.
  40:        */
  41:          hneed(sizeof(struct b_set) + (BLKLOC(arg1)->set.setsize +
  42:             BLKLOC(arg2)->set.setsize) * sizeof(struct b_selem));
  43:          /*
  44:           *  Select the larger of the two sets as the source
  45:           *  copy each element to a new set for the result
  46:           *  then insert each member of the second set into the
  47:           *  result set if it is not already there.
  48:           */
  49:          if (BLKLOC(arg1)->set.setsize >= BLKLOC(arg2)->set.setsize) {
  50:             srcp = (struct b_set *) BLKLOC(arg1);
  51:             tstp = (struct b_set *) BLKLOC(arg2);
  52:             }
  53:          else {
  54:             srcp = (struct b_set *) BLKLOC(arg2);
  55:             tstp = (struct b_set *) BLKLOC(arg1);
  56:             }
  57:          arg0.type = D_SET;
  58:          dstp = alcset();
  59:          BLKLOC(arg0) = (union block *) dstp;
  60:          for (i = 0; i < NBUCKETS; i++) {
  61:             ep = (struct b_selem *) BLKLOC(srcp->sbucks[i]);
  62:             dp = &dstp->sbucks[i];
  63:             while (ep != NULL) {
  64:                dp->type = D_SELEM;
  65:                BLKLOC(*dp) = (union block *) alcselem(&ep->setmem, ep->hnum);
  66:                dp = &BLKLOC(*dp)->selem.sblink;
  67:                dstp->setsize++;
  68:                ep = (struct b_selem *) BLKLOC(ep->sblink);
  69:                }
  70:             }
  71:          for (i = 0; i < NBUCKETS; i++) {
  72:             ep = (struct b_selem *) BLKLOC(tstp->sbucks[i]);
  73:             while (ep != NULL) {
  74:                hook = memb(dstp, &ep->setmem, ep->hnum, &res);
  75:                if (res == 0)
  76:                   addmem(dstp, alcselem(&ep->setmem,  ep->hnum), hook);
  77:                ep = (struct b_selem *) BLKLOC(ep->sblink);
  78:                }
  79:             }
  80:          }
  81:       else {
  82:       skipsets:
  83: #endif SETS
  84: 
  85:    hneed(sizeof(struct b_cset));
  86: 
  87:    /*
  88:     * x and y must be csets.
  89:     */
  90:    if (cvcset(&arg1, &cs1, csbuf1) == NULL)
  91:       runerr(104, &arg1);
  92:    if (cvcset(&arg2, &cs2, csbuf2) == NULL)
  93:       runerr(104, &arg2);
  94: 
  95:    /*
  96:     * Allocate a new cset and in each word of it, compute the value
  97:     *  of the bitwise union of the corresponding words in the
  98:     *  x and y csets.
  99:     */
 100:    bp = (union block *) alccset();
 101:    for (i = 0; i < CSETSIZE; i++)
 102:        bp->cset.bits[i] = cs1[i] | cs2[i];
 103: 
 104:    arg0.type = D_CSET;
 105:    BLKLOC(arg0) = bp;
 106: #ifdef SETS
 107:    }
 108: #endif SETS
 109:    ClearBound;
 110:    }
 111: 
 112: Opblock(unioncs,2,"++")

Defined functions

unioncs defined in line 7; used 1 times
Last modified: 1984-11-18
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