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 */
28
29 /*
30 * Author: David B. Golub, Carnegie Mellon University
31 * Date: 7/90
32 */
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, NULL },
50 { "maxoff", &db_maxoff, NULL },
51 { "maxwidth", &db_max_width, NULL },
52 { "tabstops", &db_tab_stop_width, NULL },
53 };
54 static struct db_variable *db_evars = db_vars + NELEM(db_vars);
55
56 static int
db_find_variable(struct db_variable ** varp)57 db_find_variable(struct db_variable **varp)
58 {
59 int t;
60 struct db_variable *vp;
61
62 t = db_read_token();
63 if (t == tIDENT) {
64 for (vp = db_vars; vp < db_evars; vp++) {
65 if (!strcmp(db_tok_string, vp->name)) {
66 *varp = vp;
67 return (1);
68 }
69 }
70 for (vp = db_regs; vp < db_eregs; vp++) {
71 if (!strcmp(db_tok_string, vp->name)) {
72 *varp = vp;
73 return (1);
74 }
75 }
76 }
77 db_error("Unknown variable\n");
78 return (0);
79 }
80
81 int
db_get_variable(db_expr_t * valuep)82 db_get_variable(db_expr_t *valuep)
83 {
84 struct db_variable *vp;
85
86 if (!db_find_variable(&vp))
87 return (0);
88
89 db_read_variable(vp, valuep);
90
91 return (1);
92 }
93
94 #ifdef notused
95 static int
db_set_variable(db_expr_t value)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 db_write_variable(vp, &value);
104
105 return (1);
106 }
107 #endif
108
109 void
db_read_variable(struct db_variable * vp,db_expr_t * valuep)110 db_read_variable(struct db_variable *vp, db_expr_t *valuep)
111 {
112 db_varfcn_t *func = vp->fcn;
113
114 if (func == NULL)
115 *valuep = *(vp->valuep);
116 else
117 (*func)(vp, valuep, DB_VAR_GET);
118 }
119
120 static void
db_write_variable(struct db_variable * vp,db_expr_t * valuep)121 db_write_variable(struct db_variable *vp, db_expr_t *valuep)
122 {
123 db_varfcn_t *func = vp->fcn;
124
125 if (func == NULL)
126 *(vp->valuep) = *valuep;
127 else
128 (*func)(vp, valuep, DB_VAR_SET);
129 }
130
131 void
db_set_cmd(db_expr_t dummy1,boolean_t dummy2,db_expr_t dummy3,char * dummy4)132 db_set_cmd(db_expr_t dummy1, boolean_t dummy2, db_expr_t dummy3, char *dummy4)
133 {
134 db_expr_t value;
135 struct db_variable *vp;
136 int t;
137
138 t = db_read_token();
139 if (t != tDOLLAR) {
140 db_error("Unknown variable\n");
141 return;
142 }
143 if (!db_find_variable(&vp)) {
144 db_error("Unknown variable\n");
145 return;
146 }
147
148 t = db_read_token();
149 if (t != tEQ)
150 db_unread_token(t);
151
152 if (!db_expression(&value)) {
153 db_error("No value\n");
154 return;
155 }
156 if (db_read_token() != tEOL) {
157 db_error("?\n");
158 }
159
160 db_write_variable(vp, &value);
161 }
162