xref: /onnv-gate/usr/src/tools/cscope-fast/lookup.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
23*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate 
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate  * Copyright (c) 1999 by Sun Microsystems, Inc.
28*0Sstevel@tonic-gate  * All rights reserved.
29*0Sstevel@tonic-gate  */
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  *	cscope - interactive C symbol cross-reference
35*0Sstevel@tonic-gate  *
36*0Sstevel@tonic-gate  *	keyword look-up routine for the C symbol scanner
37*0Sstevel@tonic-gate  */
38*0Sstevel@tonic-gate 
39*0Sstevel@tonic-gate #include "global.h"
40*0Sstevel@tonic-gate 
41*0Sstevel@tonic-gate /* keyword text for fast testing of keywords in the scanner */
42*0Sstevel@tonic-gate char	externtext[] = "extern";
43*0Sstevel@tonic-gate char	typedeftext[] = "typedef";
44*0Sstevel@tonic-gate 
45*0Sstevel@tonic-gate /*
46*0Sstevel@tonic-gate  * This keyword table is also used for keyword text compression.  Keywords
47*0Sstevel@tonic-gate  * with an index less than the numeric value of a space are replaced with the
48*0Sstevel@tonic-gate  * control character corresponding to the index, so they cannot be moved
49*0Sstevel@tonic-gate  * without changing the database file version and adding compatibility code
50*0Sstevel@tonic-gate  * for old databases.
51*0Sstevel@tonic-gate  */
52*0Sstevel@tonic-gate struct	keystruct keyword[] = {
53*0Sstevel@tonic-gate 	{ "#define",	' ',	MISC,	NULL },	/* must be table entry 0 */
54*0Sstevel@tonic-gate 						/* for old databases */
55*0Sstevel@tonic-gate 	{ "#include",	' ',	MISC,	NULL },	/* must be table entry 1 */
56*0Sstevel@tonic-gate 	{ "break",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
57*0Sstevel@tonic-gate 	{ "case",	' ',	FLOW,	NULL },
58*0Sstevel@tonic-gate 	{ "char",	' ',	DECL,	NULL },
59*0Sstevel@tonic-gate 	{ "continue",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
60*0Sstevel@tonic-gate 	{ "default",	'\0',	FLOW,	NULL },	/* rarely in cross-reference */
61*0Sstevel@tonic-gate 	{ "#define",	' ',	MISC,	NULL },	/* must be table entry 7 */
62*0Sstevel@tonic-gate 	{ "double",	' ',	DECL,	NULL },
63*0Sstevel@tonic-gate 	{ "\t",		'\0',	MISC,	NULL },	/* must be table entry 9 */
64*0Sstevel@tonic-gate 	{ "\n",		'\0',	MISC,	NULL },	/* must be table entry 10 */
65*0Sstevel@tonic-gate 	{ "else",	' ',	FLOW,	NULL },
66*0Sstevel@tonic-gate 	{ "enum",	' ',	DECL,	NULL },
67*0Sstevel@tonic-gate 	{ externtext,	' ',	DECL,	NULL },
68*0Sstevel@tonic-gate 	{ "float",	' ',	DECL,	NULL },
69*0Sstevel@tonic-gate 	{ "for",	'(',	FLOW,	NULL },
70*0Sstevel@tonic-gate 	{ "goto",	' ',	FLOW,	NULL },
71*0Sstevel@tonic-gate 	{ "if",		'(',	FLOW,	NULL },
72*0Sstevel@tonic-gate 	{ "int",	' ',	DECL,	NULL },
73*0Sstevel@tonic-gate 	{ "long",	' ',	DECL,	NULL },
74*0Sstevel@tonic-gate 	{ "register",	' ',	DECL,	NULL },
75*0Sstevel@tonic-gate 	{ "return",	'\0',	FLOW,	NULL },
76*0Sstevel@tonic-gate 	{ "short",	' ',	DECL,	NULL },
77*0Sstevel@tonic-gate 	{ "sizeof",	'\0',	MISC,	NULL },
78*0Sstevel@tonic-gate 	{ "static",	' ',	DECL,	NULL },
79*0Sstevel@tonic-gate 	{ "struct",	' ',	DECL,	NULL },
80*0Sstevel@tonic-gate 	{ "switch",	'(',	FLOW,	NULL },
81*0Sstevel@tonic-gate 	{ typedeftext,	' ',	DECL,	NULL },
82*0Sstevel@tonic-gate 	{ "union",	' ',	DECL,	NULL },
83*0Sstevel@tonic-gate 	{ "unsigned",	' ',	DECL,	NULL },
84*0Sstevel@tonic-gate 	{ "void",	' ',	DECL,	NULL },
85*0Sstevel@tonic-gate 	{ "while",	'(',	FLOW,	NULL },
86*0Sstevel@tonic-gate 
87*0Sstevel@tonic-gate 	/* these keywords are not compressed */
88*0Sstevel@tonic-gate 	{ "auto",	' ',	DECL,	NULL },
89*0Sstevel@tonic-gate 	{ "do",		' ',	FLOW,	NULL },
90*0Sstevel@tonic-gate 	{ "fortran",	' ',	DECL,	NULL },
91*0Sstevel@tonic-gate 	{ "const",	' ',	DECL,	NULL },
92*0Sstevel@tonic-gate 	{ "signed",	' ',	DECL,	NULL },
93*0Sstevel@tonic-gate 	{ "volatile",	' ',	DECL,	NULL },
94*0Sstevel@tonic-gate };
95*0Sstevel@tonic-gate 
96*0Sstevel@tonic-gate #define	KEYWORDS	(sizeof (keyword) / sizeof (struct keystruct))
97*0Sstevel@tonic-gate 
98*0Sstevel@tonic-gate #define	HASHMOD	(KEYWORDS * 2 + 1)
99*0Sstevel@tonic-gate 
100*0Sstevel@tonic-gate static	struct	keystruct *hashtab[HASHMOD]; /* pointer table */
101*0Sstevel@tonic-gate 
102*0Sstevel@tonic-gate /* put the keywords into the symbol table */
103*0Sstevel@tonic-gate 
104*0Sstevel@tonic-gate void
initsymtab(void)105*0Sstevel@tonic-gate initsymtab(void)
106*0Sstevel@tonic-gate {
107*0Sstevel@tonic-gate 	int	i, j;
108*0Sstevel@tonic-gate 	struct	keystruct *p;
109*0Sstevel@tonic-gate 
110*0Sstevel@tonic-gate 	for (i = 1; i < KEYWORDS; ++i) {
111*0Sstevel@tonic-gate 		p = &keyword[i];
112*0Sstevel@tonic-gate 		j = hash(p->text) % HASHMOD;
113*0Sstevel@tonic-gate 		p->next = hashtab[j];
114*0Sstevel@tonic-gate 		hashtab[j] = p;
115*0Sstevel@tonic-gate 	}
116*0Sstevel@tonic-gate }
117*0Sstevel@tonic-gate 
118*0Sstevel@tonic-gate /* see if this identifier is a keyword */
119*0Sstevel@tonic-gate 
120*0Sstevel@tonic-gate struct keystruct *
lookup(char * ident)121*0Sstevel@tonic-gate lookup(char *ident)
122*0Sstevel@tonic-gate {
123*0Sstevel@tonic-gate 	struct	keystruct *p;
124*0Sstevel@tonic-gate 	int	c;
125*0Sstevel@tonic-gate 
126*0Sstevel@tonic-gate 	/* look up the identifier in the keyword table */
127*0Sstevel@tonic-gate 	for (p = hashtab[hash(ident) % HASHMOD]; p != NULL; p = p->next) {
128*0Sstevel@tonic-gate 		if (strequal(ident, p->text)) {
129*0Sstevel@tonic-gate 			if (compress == YES && (c = p - keyword) < ' ') {
130*0Sstevel@tonic-gate 				ident[0] = c;	/* compress the keyword */
131*0Sstevel@tonic-gate 			}
132*0Sstevel@tonic-gate 			return (p);
133*0Sstevel@tonic-gate 		}
134*0Sstevel@tonic-gate 	}
135*0Sstevel@tonic-gate 	/* this is an identifier */
136*0Sstevel@tonic-gate 	return (NULL);
137*0Sstevel@tonic-gate }
138*0Sstevel@tonic-gate 
139*0Sstevel@tonic-gate /* form hash value for string */
140*0Sstevel@tonic-gate 
141*0Sstevel@tonic-gate int
hash(char * s)142*0Sstevel@tonic-gate hash(char *s)
143*0Sstevel@tonic-gate {
144*0Sstevel@tonic-gate 	unsigned i;
145*0Sstevel@tonic-gate 
146*0Sstevel@tonic-gate 	for (i = 0; *s != '\0'; )
147*0Sstevel@tonic-gate 		i += *s++;	/* += is faster than <<= for cscope */
148*0Sstevel@tonic-gate 	return (i);
149*0Sstevel@tonic-gate }
150