BSD 4_3_Net_1 release

[unix-history] / sendmail / src / stab.c

/*
* Copyright (c) 1983 Eric P. Allman
* Copyright (c) 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
static char sccsid[] = "@(#)stab.c      5.6 (Berkeley) 1/1/89";
#endif /* not lint */

# include "sendmail.h"

/*
**  STAB -- manage the symbol table
**
**      Parameters:
**              name -- the name to be looked up or inserted.
**              type -- the type of symbol.
**              op -- what to do:
**                      ST_ENTER -- enter the name if not
**                              already present.
**                      ST_FIND -- find it only.
**
**      Returns:
**              pointer to a STAB entry for this name.
**              NULL if not found and not entered.
**
**      Side Effects:
**              can update the symbol table.
*/

# define STABSIZE       400

static STAB     *SymTab[STABSIZE];

STAB *
stab(name, type, op)
       char *name;
       int type;
       int op;
{
       register STAB *s;
       register STAB **ps;
       register int hfunc;
       register char *p;
       extern char lower();

       if (tTd(36, 5))
               printf("STAB: %s %d ", name, type);

       /*
       **  Compute the hashing function
       **
       **      We could probably do better....
       */

       hfunc = type;
       for (p = name; *p != '\0'; p++)
               hfunc = (((hfunc << 7) | lower(*p)) & 077777) % STABSIZE;

       if (tTd(36, 9))
               printf("(hfunc=%d) ", hfunc);

       ps = &SymTab[hfunc];
       while ((s = *ps) != NULL && (strcasecmp(name, s->s_name) || s->s_type != type))
               ps = &s->s_next;

       /*
       **  Dispose of the entry.
       */

       if (s != NULL || op == ST_FIND)
       {
               if (tTd(36, 5))
               {
                       if (s == NULL)
                               printf("not found\n");
                       else
                       {
                               long *lp = (long *) s->s_class;

                               printf("type %d val %lx %lx %lx %lx\n",
                                       s->s_type, lp[0], lp[1], lp[2], lp[3]);
                       }
               }
               return (s);
       }

       /*
       **  Make a new entry and link it in.
       */

       if (tTd(36, 5))
               printf("entered\n");

       /* make new entry */
       s = (STAB *) xalloc(sizeof *s);
       bzero((char *) s, sizeof *s);
       s->s_name = newstr(name);
       makelower(s->s_name);
       s->s_type = type;

       /* link it in */
       *ps = s;

       return (s);
}