xref: /dragonfly/sys/ddb/db_variables.c (revision 71126e33)
1 /*
2  * Mach Operating System
3  * Copyright (c) 1991,1990 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie the
24  * rights to redistribute these changes.
25  *
26  * $FreeBSD: src/sys/ddb/db_variables.c,v 1.18 1999/08/28 00:41:11 peter Exp $
27  * $DragonFly: src/sys/ddb/db_variables.c,v 1.3 2003/08/27 10:47:13 rob Exp $
28  */
29 
30 /*
31  * 	Author: David B. Golub, Carnegie Mellon University
32  *	Date:	7/90
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 
38 #include <ddb/ddb.h>
39 #include <ddb/db_lex.h>
40 #include <ddb/db_variables.h>
41 
42 static int	db_find_variable (struct db_variable **varp);
43 static void	db_write_variable (struct db_variable *, db_expr_t *);
44 
45 #ifdef notused
46 static int	db_set_variable (db_expr_t value);
47 #endif
48 
49 static struct db_variable db_vars[] = {
50 	{ "radix",	&db_radix, FCN_NULL },
51 	{ "maxoff",	&db_maxoff, FCN_NULL },
52 	{ "maxwidth",	&db_max_width, FCN_NULL },
53 	{ "tabstops",	&db_tab_stop_width, FCN_NULL },
54 };
55 static struct db_variable *db_evars =
56 		db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
57 
58 static int
59 db_find_variable(varp)
60 	struct db_variable	**varp;
61 {
62 	int	t;
63 	struct db_variable *vp;
64 
65 	t = db_read_token();
66 	if (t == tIDENT) {
67 	    for (vp = db_vars; vp < db_evars; vp++) {
68 		if (!strcmp(db_tok_string, vp->name)) {
69 		    *varp = vp;
70 		    return (1);
71 		}
72 	    }
73 	    for (vp = db_regs; vp < db_eregs; vp++) {
74 		if (!strcmp(db_tok_string, vp->name)) {
75 		    *varp = vp;
76 		    return (1);
77 		}
78 	    }
79 	}
80 	db_error("Unknown variable\n");
81 	return (0);
82 }
83 
84 int
85 db_get_variable(valuep)
86 	db_expr_t	*valuep;
87 {
88 	struct db_variable *vp;
89 
90 	if (!db_find_variable(&vp))
91 	    return (0);
92 
93 	db_read_variable(vp, valuep);
94 
95 	return (1);
96 }
97 
98 #ifdef notused
99 static int
100 db_set_variable(value)
101 	db_expr_t	value;
102 {
103 	struct db_variable *vp;
104 
105 	if (!db_find_variable(&vp))
106 	    return (0);
107 
108 	db_write_variable(vp, &value);
109 
110 	return (1);
111 }
112 #endif
113 
114 void
115 db_read_variable(vp, valuep)
116 	struct db_variable *vp;
117 	db_expr_t	*valuep;
118 {
119 	db_varfcn_t	*func = vp->fcn;
120 
121 	if (func == FCN_NULL)
122 	    *valuep = *(vp->valuep);
123 	else
124 	    (*func)(vp, valuep, DB_VAR_GET);
125 }
126 
127 static void
128 db_write_variable(vp, valuep)
129 	struct db_variable *vp;
130 	db_expr_t	*valuep;
131 {
132 	db_varfcn_t	*func = vp->fcn;
133 
134 	if (func == FCN_NULL)
135 	    *(vp->valuep) = *valuep;
136 	else
137 	    (*func)(vp, valuep, DB_VAR_SET);
138 }
139 
140 void
141 db_set_cmd(dummy1, dummy2, dummy3, dummy4)
142 	db_expr_t	dummy1;
143 	boolean_t	dummy2;
144 	db_expr_t	dummy3;
145 	char *		dummy4;
146 {
147 	db_expr_t	value;
148 	struct db_variable *vp;
149 	int	t;
150 
151 	t = db_read_token();
152 	if (t != tDOLLAR) {
153 	    db_error("Unknown variable\n");
154 	    return;
155 	}
156 	if (!db_find_variable(&vp)) {
157 	    db_error("Unknown variable\n");
158 	    return;
159 	}
160 
161 	t = db_read_token();
162 	if (t != tEQ)
163 	    db_unread_token(t);
164 
165 	if (!db_expression(&value)) {
166 	    db_error("No value\n");
167 	    return;
168 	}
169 	if (db_read_token() != tEOL) {
170 	    db_error("?\n");
171 	}
172 
173 	db_write_variable(vp, &value);
174 }
175