Annotation of src/usr.bin/m4/look.c, Revision 1.7
1.7 ! millert 1: /* $OpenBSD: look.c,v 1.6 1999/11/20 17:48:59 espie Exp $ */
1.2 deraadt 2:
1.1 deraadt 3: /*
4: * Copyright (c) 1989, 1993
5: * The Regents of the University of California. All rights reserved.
6: *
7: * This code is derived from software contributed to Berkeley by
8: * Ozan Yigit at York University.
9: *
10: * Redistribution and use in source and binary forms, with or without
11: * modification, are permitted provided that the following conditions
12: * are met:
13: * 1. Redistributions of source code must retain the above copyright
14: * notice, this list of conditions and the following disclaimer.
15: * 2. Redistributions in binary form must reproduce the above copyright
16: * notice, this list of conditions and the following disclaimer in the
17: * documentation and/or other materials provided with the distribution.
18: * 3. All advertising materials mentioning features or use of this software
19: * must display the following acknowledgement:
20: * This product includes software developed by the University of
21: * California, Berkeley and its contributors.
22: * 4. Neither the name of the University nor the names of its contributors
23: * may be used to endorse or promote products derived from this software
24: * without specific prior written permission.
25: *
26: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36: * SUCH DAMAGE.
37: */
38:
39: #ifndef lint
40: static char sccsid[] = "@(#)look.c 8.1 (Berkeley) 6/6/93";
41: #endif /* not lint */
42:
43: /*
44: * look.c
45: * Facility: m4 macro processor
46: * by: oz
47: */
48:
49: #include <sys/types.h>
50: #include <stdio.h>
51: #include <stdlib.h>
1.3 espie 52: #include <stddef.h>
1.1 deraadt 53: #include <string.h>
54: #include "mdef.h"
55: #include "stdd.h"
56: #include "extern.h"
57:
1.5 espie 58: static void freent __P((ndptr));
59:
1.6 espie 60: unsigned
1.1 deraadt 61: hash(name)
1.5 espie 62: const char *name;
1.1 deraadt 63: {
1.7 ! millert 64: unsigned int h = 0;
1.1 deraadt 65: while (*name)
66: h = (h << 5) + h + *name++;
1.6 espie 67: return (h);
1.1 deraadt 68: }
69:
70: /*
71: * find name in the hash table
72: */
73: ndptr
74: lookup(name)
1.5 espie 75: const char *name;
1.1 deraadt 76: {
1.4 espie 77: ndptr p;
1.7 ! millert 78: unsigned int h;
1.1 deraadt 79:
1.6 espie 80: h = hash(name);
81: for (p = hashtab[h % HASHSIZE]; p != nil; p = p->nxtptr)
82: if (h == p->hv && STREQ(name, p->name))
1.1 deraadt 83: break;
84: return (p);
85: }
86:
87: /*
88: * hash and create an entry in the hash table.
89: * The new entry is added in front of a hash bucket.
90: */
91: ndptr
92: addent(name)
1.5 espie 93: const char *name;
1.1 deraadt 94: {
1.7 ! millert 95: unsigned int h;
1.1 deraadt 96: ndptr p;
97:
98: h = hash(name);
99: p = (ndptr) xalloc(sizeof(struct ndblock));
1.6 espie 100: p->nxtptr = hashtab[h % HASHSIZE];
101: hashtab[h % HASHSIZE] = p;
1.1 deraadt 102: p->name = xstrdup(name);
1.6 espie 103: p->hv = h;
1.1 deraadt 104: return p;
105: }
106:
107: static void
108: freent(p)
1.4 espie 109: ndptr p;
1.1 deraadt 110: {
111: if (!(p->type & STATIC)) {
112: free((char *) p->name);
113: if (p->defn != null)
114: free((char *) p->defn);
115: }
116: free((char *) p);
117: }
118:
119: /*
120: * remove an entry from the hashtable
121: */
122: void
123: remhash(name, all)
1.5 espie 124: const char *name;
1.4 espie 125: int all;
1.1 deraadt 126: {
1.7 ! millert 127: unsigned int h;
1.4 espie 128: ndptr xp, tp, mp;
1.1 deraadt 129:
130: h = hash(name);
1.6 espie 131: mp = hashtab[h % HASHSIZE];
1.1 deraadt 132: tp = nil;
133: while (mp != nil) {
1.6 espie 134: if (mp->hv == h && STREQ(mp->name, name)) {
1.1 deraadt 135: mp = mp->nxtptr;
136: if (tp == nil) {
1.6 espie 137: freent(hashtab[h % HASHSIZE]);
138: hashtab[h % HASHSIZE] = mp;
1.1 deraadt 139: }
140: else {
141: xp = tp->nxtptr;
142: tp->nxtptr = mp;
143: freent(xp);
144: }
145: if (!all)
146: break;
147: }
148: else {
149: tp = mp;
150: mp = mp->nxtptr;
151: }
152: }
153: }