xref: /freebsd/sys/ddb/db_variables.c (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
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 
43 static struct db_variable db_vars[] = {
44 	{ "radix",	&db_radix, FCN_NULL },
45 	{ "maxoff",	&db_maxoff, FCN_NULL },
46 	{ "maxwidth",	&db_max_width, FCN_NULL },
47 	{ "tabstops",	&db_tab_stop_width, FCN_NULL },
48 	{ "lines",	&db_lines_per_page, FCN_NULL },
49 	{ "curcpu",	NULL, db_var_curcpu },
50 	{ "db_cpu",	NULL, db_var_db_cpu },
51 #ifdef VIMAGE
52 	{ "curvnet",	NULL, db_var_curvnet },
53 	{ "db_vnet",	NULL, db_var_db_vnet },
54 #endif
55 };
56 static struct db_variable *db_evars = db_vars + nitems(db_vars);
57 
58 static int
59 db_find_variable(struct db_variable **varp)
60 {
61 	struct db_variable *vp;
62 	int t;
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(db_expr_t *valuep)
85 {
86 	struct db_variable *vp;
87 
88 	if (!db_find_variable(&vp))
89 		return (0);
90 
91 	return (db_read_variable(vp, valuep));
92 }
93 
94 int
95 db_set_variable(db_expr_t value)
96 {
97 	struct db_variable *vp;
98 
99 	if (!db_find_variable(&vp))
100 		return (0);
101 
102 	return (db_write_variable(vp, value));
103 }
104 
105 int
106 db_read_variable(struct db_variable *vp, db_expr_t *valuep)
107 {
108 	db_varfcn_t *func = vp->fcn;
109 
110 	if (func == FCN_NULL) {
111 		*valuep = *(vp->valuep);
112 		return (1);
113 	}
114 	return ((*func)(vp, valuep, DB_VAR_GET));
115 }
116 
117 int
118 db_write_variable(struct db_variable *vp, db_expr_t value)
119 {
120 	db_varfcn_t *func = vp->fcn;
121 
122 	if (func == FCN_NULL) {
123 		*(vp->valuep) = value;
124 		return (1);
125 	}
126 	return ((*func)(vp, &value, DB_VAR_SET));
127 }
128 
129 void
130 db_set_cmd(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
131 {
132 	struct db_variable *vp;
133 	db_expr_t value;
134 	int t;
135 
136 	t = db_read_token();
137 	if (t != tDOLLAR) {
138 		db_error("Unknown variable\n");
139 		return;
140 	}
141 	if (!db_find_variable(&vp)) {
142 		db_error("Unknown variable\n");
143 		return;
144 	}
145 
146 	t = db_read_token();
147 	if (t != tEQ)
148 		db_unread_token(t);
149 
150 	if (!db_expression(&value)) {
151 		db_error("No value\n");
152 		return;
153 	}
154 	if (db_read_token() != tEOL)
155 		db_error("?\n");
156 
157 	db_write_variable(vp, value);
158 }
159