xref: /csrg-svn/usr.sbin/sendmail/src/stab.c (revision 33725)
1 /*
2 **  Sendmail
3 **  Copyright (c) 1983  Eric P. Allman
4 **  Berkeley, California
5 **
6 **  Copyright (c) 1983 Regents of the University of California.
7 **  All rights reserved.  The Berkeley software License Agreement
8 **  specifies the terms and conditions for redistribution.
9 */
10 
11 #ifndef lint
12 static char	SccsId[] = "@(#)stab.c	5.3 (Berkeley) 03/13/88";
13 #endif not lint
14 
15 # include "sendmail.h"
16 
17 /*
18 **  STAB -- manage the symbol table
19 **
20 **	Parameters:
21 **		name -- the name to be looked up or inserted.
22 **		type -- the type of symbol.
23 **		op -- what to do:
24 **			ST_ENTER -- enter the name if not
25 **				already present.
26 **			ST_FIND -- find it only.
27 **
28 **	Returns:
29 **		pointer to a STAB entry for this name.
30 **		NULL if not found and not entered.
31 **
32 **	Side Effects:
33 **		can update the symbol table.
34 */
35 
36 # define STABSIZE	400
37 
38 static STAB	*SymTab[STABSIZE];
39 
40 STAB *
41 stab(name, type, op)
42 	char *name;
43 	int type;
44 	int op;
45 {
46 	register STAB *s;
47 	register STAB **ps;
48 	register int hfunc;
49 	register char *p;
50 	extern char lower();
51 
52 # ifdef DEBUG
53 	if (tTd(36, 5))
54 		printf("STAB: %s %d ", name, type);
55 # endif DEBUG
56 
57 	/*
58 	**  Compute the hashing function
59 	**
60 	**	We could probably do better....
61 	*/
62 
63 	hfunc = type;
64 	for (p = name; *p != '\0'; p++)
65 		hfunc = (((hfunc << 7) | lower(*p)) & 077777) % STABSIZE;
66 
67 # ifdef DEBUG
68 	if (tTd(36, 9))
69 		printf("(hfunc=%d) ", hfunc);
70 # endif DEBUG
71 
72 	ps = &SymTab[hfunc];
73 	while ((s = *ps) != NULL && (strcasecmp(name, s->s_name) || s->s_type != type))
74 		ps = &s->s_next;
75 
76 	/*
77 	**  Dispose of the entry.
78 	*/
79 
80 	if (s != NULL || op == ST_FIND)
81 	{
82 # ifdef DEBUG
83 		if (tTd(36, 5))
84 		{
85 			if (s == NULL)
86 				printf("not found\n");
87 			else
88 			{
89 				long *lp = (long *) s->s_class;
90 
91 				printf("type %d val %lx %lx %lx %lx\n",
92 					s->s_type, lp[0], lp[1], lp[2], lp[3]);
93 			}
94 		}
95 # endif DEBUG
96 		return (s);
97 	}
98 
99 	/*
100 	**  Make a new entry and link it in.
101 	*/
102 
103 # ifdef DEBUG
104 	if (tTd(36, 5))
105 		printf("entered\n");
106 # endif DEBUG
107 
108 	/* make new entry */
109 	s = (STAB *) xalloc(sizeof *s);
110 	bzero((char *) s, sizeof *s);
111 	s->s_name = newstr(name);
112 	makelower(s->s_name);
113 	s->s_type = type;
114 
115 	/* link it in */
116 	*ps = s;
117 
118 	return (s);
119 }
120