xref: /freebsd/sys/ddb/db_variables.c (revision 71e8eac4fd89dedbcb4130379add151d3ed942fa)
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 =
57 	db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
58 
59 static int
60 db_find_variable(struct db_variable **varp)
61 {
62 	struct db_variable *vp;
63 	int t;
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(db_expr_t *valuep)
86 {
87 	struct db_variable *vp;
88 
89 	if (!db_find_variable(&vp))
90 		return (0);
91 
92 	return (db_read_variable(vp, valuep));
93 }
94 
95 int
96 db_set_variable(db_expr_t value)
97 {
98 	struct db_variable *vp;
99 
100 	if (!db_find_variable(&vp))
101 		return (0);
102 
103 	return (db_write_variable(vp, value));
104 }
105 
106 int
107 db_read_variable(struct db_variable *vp, db_expr_t *valuep)
108 {
109 	db_varfcn_t *func = vp->fcn;
110 
111 	if (func == FCN_NULL) {
112 		*valuep = *(vp->valuep);
113 		return (1);
114 	}
115 	return ((*func)(vp, valuep, DB_VAR_GET));
116 }
117 
118 int
119 db_write_variable(struct db_variable *vp, db_expr_t value)
120 {
121 	db_varfcn_t *func = vp->fcn;
122 
123 	if (func == FCN_NULL) {
124 		*(vp->valuep) = value;
125 		return (1);
126 	}
127 	return ((*func)(vp, &value, DB_VAR_SET));
128 }
129 
130 void
131 db_set_cmd(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
132 {
133 	struct db_variable *vp;
134 	db_expr_t value;
135 	int t;
136 
137 	t = db_read_token();
138 	if (t != tDOLLAR) {
139 		db_error("Unknown variable\n");
140 		return;
141 	}
142 	if (!db_find_variable(&vp)) {
143 		db_error("Unknown variable\n");
144 		return;
145 	}
146 
147 	t = db_read_token();
148 	if (t != tEQ)
149 		db_unread_token(t);
150 
151 	if (!db_expression(&value)) {
152 		db_error("No value\n");
153 		return;
154 	}
155 	if (db_read_token() != tEOL)
156 		db_error("?\n");
157 
158 	db_write_variable(vp, value);
159 }
160