1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*	Copyright (c) 1988 AT&T	*/
23/*	  All Rights Reserved  	*/
24
25
26/*
27 * Copyright (c) 1999 by Sun Microsystems, Inc.
28 * All rights reserved.
29 */
30
31#pragma ident	"%Z%%M%	%I%	%E% SMI"
32
33/*
34 *	cscope - interactive C symbol cross-reference
35 *
36 *	keyword look-up routine for the C symbol scanner
37 */
38
39#include "global.h"
40
41/* keyword text for fast testing of keywords in the scanner */
42char	externtext[] = "extern";
43char	typedeftext[] = "typedef";
44
45/*
46 * This keyword table is also used for keyword text compression.  Keywords
47 * with an index less than the numeric value of a space are replaced with the
48 * control character corresponding to the index, so they cannot be moved
49 * without changing the database file version and adding compatibility code
50 * for old databases.
51 */
52struct	keystruct keyword[] = {
53	{ "#define",	' ',	MISC,	NULL },	/* must be table entry 0 */
54						/* for old databases */
55	{ "#include",	' ',	MISC,	NULL },	/* must be table entry 1 */
56	{ "break",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
57	{ "case",	' ',	FLOW,	NULL },
58	{ "char",	' ',	DECL,	NULL },
59	{ "continue",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
60	{ "default",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
61	{ "#define",	' ',	MISC,	NULL },	/* must be table entry 7 */
62	{ "double",	' ',	DECL,	NULL },
63	{ "\t",		'\0',	MISC,	NULL },	/* must be table entry 9 */
64	{ "\n",		'\0',	MISC,	NULL },	/* must be table entry 10 */
65	{ "else",	' ',	FLOW,	NULL },
66	{ "enum",	' ',	DECL,	NULL },
67	{ externtext,	' ',	DECL,	NULL },
68	{ "float",	' ',	DECL,	NULL },
69	{ "for",	'(',	FLOW,	NULL },
70	{ "goto",	' ',	FLOW,	NULL },
71	{ "if",		'(',	FLOW,	NULL },
72	{ "int",	' ',	DECL,	NULL },
73	{ "long",	' ',	DECL,	NULL },
74	{ "register",	' ',	DECL,	NULL },
75	{ "return",	'\0',	FLOW,	NULL },
76	{ "short",	' ',	DECL,	NULL },
77	{ "sizeof",	'\0',	MISC,	NULL },
78	{ "static",	' ',	DECL,	NULL },
79	{ "struct",	' ',	DECL,	NULL },
80	{ "switch",	'(',	FLOW,	NULL },
81	{ typedeftext,	' ',	DECL,	NULL },
82	{ "union",	' ',	DECL,	NULL },
83	{ "unsigned",	' ',	DECL,	NULL },
84	{ "void",	' ',	DECL,	NULL },
85	{ "while",	'(',	FLOW,	NULL },
86
87	/* these keywords are not compressed */
88	{ "auto",	' ',	DECL,	NULL },
89	{ "do",		' ',	FLOW,	NULL },
90	{ "fortran",	' ',	DECL,	NULL },
91	{ "const",	' ',	DECL,	NULL },
92	{ "signed",	' ',	DECL,	NULL },
93	{ "volatile",	' ',	DECL,	NULL },
94};
95
96#define	KEYWORDS	(sizeof (keyword) / sizeof (struct keystruct))
97
98#define	HASHMOD	(KEYWORDS * 2 + 1)
99
100static	struct	keystruct *hashtab[HASHMOD]; /* pointer table */
101
102/* put the keywords into the symbol table */
103
104void
105initsymtab(void)
106{
107	int	i, j;
108	struct	keystruct *p;
109
110	for (i = 1; i < KEYWORDS; ++i) {
111		p = &keyword[i];
112		j = hash(p->text) % HASHMOD;
113		p->next = hashtab[j];
114		hashtab[j] = p;
115	}
116}
117
118/* see if this identifier is a keyword */
119
120struct keystruct *
121lookup(char *ident)
122{
123	struct	keystruct *p;
124	int	c;
125
126	/* look up the identifier in the keyword table */
127	for (p = hashtab[hash(ident) % HASHMOD]; p != NULL; p = p->next) {
128		if (strequal(ident, p->text)) {
129			if (compress == YES && (c = p - keyword) < ' ') {
130				ident[0] = c;	/* compress the keyword */
131			}
132			return (p);
133		}
134	}
135	/* this is an identifier */
136	return (NULL);
137}
138
139/* form hash value for string */
140
141int
142hash(char *s)
143{
144	unsigned i;
145
146	for (i = 0; *s != '\0'; )
147		i += *s++;	/* += is faster than <<= for cscope */
148	return (i);
149}
150