xref: /freebsd/sys/ddb/db_variables.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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 /*
27  * 	Author: David B. Golub, Carnegie Mellon University
28  *	Date:	7/90
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 
37 #include <ddb/ddb.h>
38 #include <ddb/db_lex.h>
39 #include <ddb/db_variables.h>
40 
41 static int	db_find_variable(struct db_variable **varp);
42 static void	db_write_variable(struct db_variable *, db_expr_t *);
43 
44 #ifdef notused
45 static int	db_set_variable(db_expr_t value);
46 #endif
47 
48 static struct db_variable db_vars[] = {
49 	{ "radix",	&db_radix, FCN_NULL },
50 	{ "maxoff",	&db_maxoff, FCN_NULL },
51 	{ "maxwidth",	&db_max_width, FCN_NULL },
52 	{ "tabstops",	&db_tab_stop_width, FCN_NULL },
53 };
54 static struct db_variable *db_evars =
55 		db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
56 
57 static int
58 db_find_variable(varp)
59 	struct db_variable	**varp;
60 {
61 	int	t;
62 	struct db_variable *vp;
63 
64 	t = db_read_token();
65 	if (t == tIDENT) {
66 	    for (vp = db_vars; vp < db_evars; vp++) {
67 		if (!strcmp(db_tok_string, vp->name)) {
68 		    *varp = vp;
69 		    return (1);
70 		}
71 	    }
72 	    for (vp = db_regs; vp < db_eregs; vp++) {
73 		if (!strcmp(db_tok_string, vp->name)) {
74 		    *varp = vp;
75 		    return (1);
76 		}
77 	    }
78 	}
79 	db_error("Unknown variable\n");
80 	return (0);
81 }
82 
83 int
84 db_get_variable(valuep)
85 	db_expr_t	*valuep;
86 {
87 	struct db_variable *vp;
88 
89 	if (!db_find_variable(&vp))
90 	    return (0);
91 
92 	db_read_variable(vp, valuep);
93 
94 	return (1);
95 }
96 
97 #ifdef notused
98 static int
99 db_set_variable(value)
100 	db_expr_t	value;
101 {
102 	struct db_variable *vp;
103 
104 	if (!db_find_variable(&vp))
105 	    return (0);
106 
107 	db_write_variable(vp, &value);
108 
109 	return (1);
110 }
111 #endif
112 
113 void
114 db_read_variable(vp, valuep)
115 	struct db_variable *vp;
116 	db_expr_t	*valuep;
117 {
118 	db_varfcn_t	*func = vp->fcn;
119 
120 	if (func == FCN_NULL)
121 	    *valuep = *(vp->valuep);
122 	else
123 	    (*func)(vp, valuep, DB_VAR_GET);
124 }
125 
126 static void
127 db_write_variable(vp, valuep)
128 	struct db_variable *vp;
129 	db_expr_t	*valuep;
130 {
131 	db_varfcn_t	*func = vp->fcn;
132 
133 	if (func == FCN_NULL)
134 	    *(vp->valuep) = *valuep;
135 	else
136 	    (*func)(vp, valuep, DB_VAR_SET);
137 }
138 
139 void
140 db_set_cmd(dummy1, dummy2, dummy3, dummy4)
141 	db_expr_t	dummy1;
142 	boolean_t	dummy2;
143 	db_expr_t	dummy3;
144 	char *		dummy4;
145 {
146 	db_expr_t	value;
147 	struct db_variable *vp;
148 	int	t;
149 
150 	t = db_read_token();
151 	if (t != tDOLLAR) {
152 	    db_error("Unknown variable\n");
153 	    return;
154 	}
155 	if (!db_find_variable(&vp)) {
156 	    db_error("Unknown variable\n");
157 	    return;
158 	}
159 
160 	t = db_read_token();
161 	if (t != tEQ)
162 	    db_unread_token(t);
163 
164 	if (!db_expression(&value)) {
165 	    db_error("No value\n");
166 	    return;
167 	}
168 	if (db_read_token() != tEOL) {
169 	    db_error("?\n");
170 	}
171 
172 	db_write_variable(vp, &value);
173 }
174