Subversion Repositories System09

/*
 *      install --- add a symbol to the table
 */
install(str,val)
char    *str;
int     val;
{
        struct link *lp;
 struct nlist *np,*p,*backp;
 int     i;
 char *LastChar();      /* ver TER_2.0 */
 
 if( !alpha(*str) ){
  error("Illegal Symbol Name");
  return(NO);
  }
 if( (np = lookup(str)) != NULL ){
  if (*LastChar(str) == '@') {  /* redefinable symbol  ver TER_2.0 */
        np->def = val;          /* redefined */
        return(YES);
        }
  if( Pass==2 ){
   np->def2 = 2;        /* defined for this pass=Pass  ver TER_2.0 */
   if( np->def == val )
    return(YES);
   else{
    error("Phasing Error");
    return(NO);
    }
   }
  error("Symbol Redefined");
  return(NO);
  }
 /* enter new symbol */
#ifdef DEBUG
 printf("Installing %s as %d\n",str,val);
#endif
 np = (struct nlist *) alloc(sizeof(struct nlist));
 if( np == (struct nlist *)ERR ){
  error("Symbol table full");
  return(NO);
  }
 np->name = alloc(strlen(str)+1);
 if( np->name == (char *)ERR ){
  error("Symbol table full");
  return(NO);
  }
 strcpy(np->name,str);
 np->def = val;
 np->def2 = 1;  /* defined for this pass=Pass  ver TER_2.0 */
 np->Lnext = NULL;
        np->Rnext = NULL;
           lp = (struct link *) alloc(sizeof(struct link));
           np->L_list = lp;
           lp->L_num = Line_num;
           lp->next = NULL;
        p = root;
          backp = NULL;
           while (p != NULL)
            {
              backp = p;
              i = strcmp (str,p->name);
               if (i<0)
                   p=p->Lnext;
                  else p=p->Rnext;
            }
          if (backp == NULL)
              root = np;
             else if (strcmp(str,backp->name)<0)
                  backp->Lnext = np;
                 else backp->Rnext = np;
          return (YES);
}
 
/*
 *      lookup --- find string in symbol table
 */
struct nlist *
lookup(char *name)
{
 struct nlist *np;
 int     i;
 char   *c;     /* ver TER_2.0 */
 
 c = name;      /* copy symbol pointer */
 while(alphan(*c))      /* search for end of symbol */
  c++;  /* next char */
 *c = EOS;      /* disconnect anything after for good compare */
                /* end of mods for ver TER_2.0 */
 
        np = root;      /* and now go on and look for symbol */
         while (np != NULL)
          {
            i = strcmp(name,np->name);
             if (i == 0)
               {
                 Last_sym = np->def;
                 return (np);
               }
             else if (i < 0)
                 np = np->Lnext;
                else np = np->Rnext;
          }
      Last_sym = 0;
/*      if (Pass == 2)
        error ("symbol Undefined on pass 2"); */
                /* commented out ver TER_2.0 2 Jul 89 */
                /* function used in IFD */
        return (NULL);
}
 
 
#define NMNE (sizeof(table)/ sizeof(struct oper))
#define NPSE (sizeof(pseudo)/ sizeof(struct oper))
/*
 *      mne_look --- mnemonic lookup
 *
 *      Return pointer to an oper structure if found.
 *      Searches both the machine mnemonic table and the pseudo table.
 */
struct oper *
mne_look(str)
char    *str;
{
 struct oper *low,*high,*mid;
 int     cond;
 
 /* Search machine mnemonics first */
 low =  &table[0];
 high = &table[ NMNE-1 ];
 while (low <= high){
  mid = low + (high-low)/2;
  if( ( cond = strcmp(str,mid->mnemonic)) < 0)
   high = mid - 1;
  else if (cond > 0)
   low = mid + 1;
  else
   return(mid);
 }
 
 /* Check for pseudo ops */
 low =  &pseudo[0];
 high = &pseudo[ NPSE-1 ];
 while (low <= high){
  mid = low + (high-low)/2;
  if( ( cond = strcmp(str,mid->mnemonic)) < 0)
   high = mid - 1;
  else if (cond > 0)
   low = mid + 1;
  else
   return(mid);
 }
 
 return(NULL);
}