xref: /netbsd-src/sys/ddb/db_variables.c (revision 4d7e773266e3c3f48566c86c0ad52d51c6454fd1)
1 /*	$NetBSD: db_variables.c,v 1.11 1997/02/04 00:33:32 cgd Exp $	*/
2 
3 /*
4  * Mach Operating System
5  * Copyright (c) 1991,1990 Carnegie Mellon University
6  * All Rights Reserved.
7  *
8  * Permission to use, copy, modify and distribute this software and its
9  * documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie the
26  * rights to redistribute these changes.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/proc.h>
31 #include <vm/vm.h>
32 #include <sys/sysctl.h>
33 
34 #include <machine/db_machdep.h>
35 
36 #include <ddb/db_lex.h>
37 #include <ddb/db_variables.h>
38 #include <ddb/db_command.h>
39 #include <ddb/db_sym.h>
40 #include <ddb/db_extern.h>
41 
42 /*
43  * If this is non-zero, the DDB will be entered when the system
44  * panics.  Initialize it so that it's patchable.
45  */
46 #ifndef DDB_ONPANIC
47 #define DDB_ONPANIC	1
48 #endif
49 int		db_onpanic = DDB_ONPANIC;
50 
51 extern unsigned int db_maxoff;
52 
53 extern int	db_radix;
54 extern int	db_max_width;
55 extern int	db_tab_stop_width;
56 extern int	db_max_line;
57 
58 static int	db_rw_internal_variable __P((struct db_variable *, db_expr_t *,
59 		    int));
60 
61 /* XXX must all be ints for sysctl. */
62 struct db_variable db_vars[] = {
63 	{ "radix",	(long *)&db_radix,	db_rw_internal_variable },
64 	{ "maxoff",	(long *)&db_maxoff,	db_rw_internal_variable },
65 	{ "maxwidth",	(long *)&db_max_width,	db_rw_internal_variable },
66 	{ "tabstops",	(long *)&db_tab_stop_width, db_rw_internal_variable },
67 	{ "lines",	(long *)&db_max_line,	db_rw_internal_variable },
68 	{ "onpanic",	(long *)&db_onpanic,	db_rw_internal_variable },
69 };
70 struct db_variable *db_evars = db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
71 
72 /*
73  * ddb command line access to the DDB variables defined above.
74  */
75 static int
76 db_rw_internal_variable(vp, valp, rw)
77 	struct db_variable *vp;
78 	db_expr_t *valp;
79 	int rw;
80 {
81 
82 	if (rw == DB_VAR_GET) {
83 		*valp = *(int *)vp->valuep;
84 	} else {
85 		*(int *)vp->valuep = *valp;
86 	}
87 	return (0);
88 }
89 
90 /*
91  * sysctl(3) access to the DDB variables defined above.
92  */
93 int
94 ddb_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
95 	int	*name;
96 	u_int	namelen;
97 	void	*oldp;
98 	size_t	*oldlenp;
99 	void	*newp;
100 	size_t	newlen;
101 	struct proc *p;
102 {
103 
104 	/* All sysctl names at this level are terminal. */
105 	if (namelen != 1)
106 		return (ENOTDIR);
107 
108 	switch (name[0]) {
109 	case DDBCTL_RADIX:
110 		return (sysctl_int(oldp, oldlenp, newp, newlen, &db_radix));
111 
112 	case DDBCTL_MAXOFF:
113 		return (sysctl_int(oldp, oldlenp, newp, newlen, &db_maxoff));
114 
115 	case DDBCTL_MAXWIDTH:
116 		return (sysctl_int(oldp, oldlenp, newp, newlen,
117 		    &db_max_width));
118 
119 	case DDBCTL_TABSTOPS:
120 		return (sysctl_int(oldp, oldlenp, newp, newlen,
121 		    &db_tab_stop_width));
122 
123 	case DDBCTL_LINES:
124 		return (sysctl_int(oldp, oldlenp, newp, newlen, &db_max_line));
125 
126 	case DDBCTL_ONPANIC:
127 		return (sysctl_int(oldp, oldlenp, newp, newlen, &db_onpanic));
128 	}
129 
130 	return (EOPNOTSUPP);
131 }
132 
133 int
134 db_find_variable(varp)
135 	struct db_variable	**varp;
136 {
137 	int	t;
138 	struct db_variable *vp;
139 
140 	t = db_read_token();
141 	if (t == tIDENT) {
142 	    for (vp = db_vars; vp < db_evars; vp++) {
143 		if (!strcmp(db_tok_string, vp->name)) {
144 		    *varp = vp;
145 		    return (1);
146 		}
147 	    }
148 	    for (vp = db_regs; vp < db_eregs; vp++) {
149 		if (!strcmp(db_tok_string, vp->name)) {
150 		    *varp = vp;
151 		    return (1);
152 		}
153 	    }
154 	}
155 	db_error("Unknown variable\n");
156 	/*NOTREACHED*/
157 	return 0;
158 }
159 
160 int
161 db_get_variable(valuep)
162 	db_expr_t	*valuep;
163 {
164 	struct db_variable *vp;
165 
166 	if (!db_find_variable(&vp))
167 	    return (0);
168 
169 	db_read_variable(vp, valuep);
170 
171 	return (1);
172 }
173 
174 int
175 db_set_variable(value)
176 	db_expr_t	value;
177 {
178 	struct db_variable *vp;
179 
180 	if (!db_find_variable(&vp))
181 	    return (0);
182 
183 	db_write_variable(vp, &value);
184 
185 	return (1);
186 }
187 
188 
189 void
190 db_read_variable(vp, valuep)
191 	struct db_variable *vp;
192 	db_expr_t	*valuep;
193 {
194 	int	(*func) __P((struct db_variable *, db_expr_t *, int)) = vp->fcn;
195 
196 	if (func == FCN_NULL)
197 	    *valuep = *(vp->valuep);
198 	else
199 	    (*func)(vp, valuep, DB_VAR_GET);
200 }
201 
202 void
203 db_write_variable(vp, valuep)
204 	struct db_variable *vp;
205 	db_expr_t	*valuep;
206 {
207 	int	(*func) __P((struct db_variable *, db_expr_t *, int)) = vp->fcn;
208 
209 	if (func == FCN_NULL)
210 	    *(vp->valuep) = *valuep;
211 	else
212 	    (*func)(vp, valuep, DB_VAR_SET);
213 }
214 
215 /*ARGSUSED*/
216 void
217 db_set_cmd(addr, have_addr, count, modif)
218 	db_expr_t	addr;
219 	int		have_addr;
220 	db_expr_t	count;
221 	char *		modif;
222 {
223 	db_expr_t	value;
224 	struct db_variable *vp;
225 	int	t;
226 
227 	t = db_read_token();
228 	if (t != tDOLLAR) {
229 	    db_error("Unknown variable\n");
230 	    /*NOTREACHED*/
231 	}
232 	if (!db_find_variable(&vp)) {
233 	    db_error("Unknown variable\n");
234 	    /*NOTREACHED*/
235 	}
236 
237 	t = db_read_token();
238 	if (t != tEQ)
239 	    db_unread_token(t);
240 
241 	if (!db_expression(&value)) {
242 	    db_error("No value\n");
243 	    /*NOTREACHED*/
244 	}
245 	if (db_read_token() != tEOL) {
246 	    db_error("?\n");
247 	    /*NOTREACHED*/
248 	}
249 
250 	db_write_variable(vp, &value);
251 }
252