xref: /netbsd-src/sys/ddb/db_break.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: db_break.c,v 1.7 1996/03/30 22:30:03 christos 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  *	Author: David B. Golub, Carnegie Mellon University
29  *	Date:	7/90
30  */
31 
32 /*
33  * Breakpoints.
34  */
35 #include <sys/param.h>
36 #include <sys/proc.h>
37 
38 #include <machine/db_machdep.h>		/* type definitions */
39 
40 #include <ddb/db_lex.h>
41 #include <ddb/db_access.h>
42 #include <ddb/db_sym.h>
43 #include <ddb/db_break.h>
44 #include <ddb/db_output.h>
45 
46 #define	NBREAKPOINTS	100
47 struct db_breakpoint	db_break_table[NBREAKPOINTS];
48 db_breakpoint_t		db_next_free_breakpoint = &db_break_table[0];
49 db_breakpoint_t		db_free_breakpoints = 0;
50 db_breakpoint_t		db_breakpoint_list = 0;
51 
52 db_breakpoint_t
53 db_breakpoint_alloc()
54 {
55 	register db_breakpoint_t	bkpt;
56 
57 	if ((bkpt = db_free_breakpoints) != 0) {
58 	    db_free_breakpoints = bkpt->link;
59 	    return (bkpt);
60 	}
61 	if (db_next_free_breakpoint == &db_break_table[NBREAKPOINTS]) {
62 	    db_printf("All breakpoints used.\n");
63 	    return (0);
64 	}
65 	bkpt = db_next_free_breakpoint;
66 	db_next_free_breakpoint++;
67 
68 	return (bkpt);
69 }
70 
71 void
72 db_breakpoint_free(bkpt)
73 	register db_breakpoint_t	bkpt;
74 {
75 	bkpt->link = db_free_breakpoints;
76 	db_free_breakpoints = bkpt;
77 }
78 
79 void
80 db_set_breakpoint(map, addr, count)
81 	vm_map_t	map;
82 	db_addr_t	addr;
83 	int		count;
84 {
85 	register db_breakpoint_t	bkpt;
86 
87 	if (db_find_breakpoint(map, addr)) {
88 	    db_printf("Already set.\n");
89 	    return;
90 	}
91 
92 	bkpt = db_breakpoint_alloc();
93 	if (bkpt == 0) {
94 	    db_printf("Too many breakpoints.\n");
95 	    return;
96 	}
97 
98 	bkpt->map = map;
99 	bkpt->address = addr;
100 	bkpt->flags = 0;
101 	bkpt->init_count = count;
102 	bkpt->count = count;
103 
104 	bkpt->link = db_breakpoint_list;
105 	db_breakpoint_list = bkpt;
106 }
107 
108 void
109 db_delete_breakpoint(map, addr)
110 	vm_map_t	map;
111 	db_addr_t	addr;
112 {
113 	register db_breakpoint_t	bkpt;
114 	register db_breakpoint_t	*prev;
115 
116 	for (prev = &db_breakpoint_list;
117 	     (bkpt = *prev) != 0;
118 	     prev = &bkpt->link) {
119 	    if (db_map_equal(bkpt->map, map) &&
120 		(bkpt->address == addr)) {
121 		*prev = bkpt->link;
122 		break;
123 	    }
124 	}
125 	if (bkpt == 0) {
126 	    db_printf("Not set.\n");
127 	    return;
128 	}
129 
130 	db_breakpoint_free(bkpt);
131 }
132 
133 db_breakpoint_t
134 db_find_breakpoint(map, addr)
135 	vm_map_t	map;
136 	db_addr_t	addr;
137 {
138 	register db_breakpoint_t	bkpt;
139 
140 	for (bkpt = db_breakpoint_list;
141 	     bkpt != 0;
142 	     bkpt = bkpt->link)
143 	{
144 	    if (db_map_equal(bkpt->map, map) &&
145 		(bkpt->address == addr))
146 		return (bkpt);
147 	}
148 	return (0);
149 }
150 
151 db_breakpoint_t
152 db_find_breakpoint_here(addr)
153 	db_addr_t	addr;
154 {
155     return db_find_breakpoint(db_map_addr(addr), addr);
156 }
157 
158 boolean_t	db_breakpoints_inserted = TRUE;
159 
160 void
161 db_set_breakpoints()
162 {
163 	register db_breakpoint_t	bkpt;
164 
165 	if (!db_breakpoints_inserted) {
166 
167 	    for (bkpt = db_breakpoint_list;
168 	         bkpt != 0;
169 	         bkpt = bkpt->link)
170 		if (db_map_current(bkpt->map)) {
171 		    bkpt->bkpt_inst = db_get_value(bkpt->address,
172 						   BKPT_SIZE,
173 						   FALSE);
174 		    db_put_value(bkpt->address,
175 				 BKPT_SIZE,
176 				 BKPT_SET(bkpt->bkpt_inst));
177 		}
178 	    db_breakpoints_inserted = TRUE;
179 	}
180 }
181 
182 void
183 db_clear_breakpoints()
184 {
185 	register db_breakpoint_t	bkpt;
186 
187 	if (db_breakpoints_inserted) {
188 
189 	    for (bkpt = db_breakpoint_list;
190 	         bkpt != 0;
191 		 bkpt = bkpt->link)
192 		if (db_map_current(bkpt->map)) {
193 		    db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst);
194 		}
195 	    db_breakpoints_inserted = FALSE;
196 	}
197 }
198 
199 /*
200  * Set a temporary breakpoint.
201  * The instruction is changed immediately,
202  * so the breakpoint does not have to be on the breakpoint list.
203  */
204 db_breakpoint_t
205 db_set_temp_breakpoint(addr)
206 	db_addr_t	addr;
207 {
208 	register db_breakpoint_t	bkpt;
209 
210 	bkpt = db_breakpoint_alloc();
211 	if (bkpt == 0) {
212 	    db_printf("Too many breakpoints.\n");
213 	    return 0;
214 	}
215 
216 	bkpt->map = NULL;
217 	bkpt->address = addr;
218 	bkpt->flags = BKPT_TEMP;
219 	bkpt->init_count = 1;
220 	bkpt->count = 1;
221 
222 	bkpt->bkpt_inst = db_get_value(bkpt->address, BKPT_SIZE, FALSE);
223 	db_put_value(bkpt->address, BKPT_SIZE, BKPT_SET(bkpt->bkpt_inst));
224 	return bkpt;
225 }
226 
227 void
228 db_delete_temp_breakpoint(bkpt)
229 	db_breakpoint_t	bkpt;
230 {
231 	db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst);
232 	db_breakpoint_free(bkpt);
233 }
234 
235 /*
236  * List breakpoints.
237  */
238 void
239 db_list_breakpoints()
240 {
241 	register db_breakpoint_t	bkpt;
242 
243 	if (db_breakpoint_list == 0) {
244 	    db_printf("No breakpoints set\n");
245 	    return;
246 	}
247 
248 	db_printf(" Map      Count    Address\n");
249 	for (bkpt = db_breakpoint_list;
250 	     bkpt != 0;
251 	     bkpt = bkpt->link)
252 	{
253 	    db_printf("%s%p %5d    ",
254 		      db_map_current(bkpt->map) ? "*" : " ",
255 		      bkpt->map, bkpt->init_count);
256 	    db_printsym(bkpt->address, DB_STGY_PROC);
257 	    db_printf("\n");
258 	}
259 }
260 
261 /* Delete breakpoint */
262 /*ARGSUSED*/
263 void
264 db_delete_cmd(addr, have_addr, count, modif)
265 	db_expr_t	addr;
266 	int		have_addr;
267 	db_expr_t	count;
268 	char *		modif;
269 {
270 	db_delete_breakpoint(db_map_addr(addr), (db_addr_t)addr);
271 }
272 
273 /* Set breakpoint with skip count */
274 /*ARGSUSED*/
275 void
276 db_breakpoint_cmd(addr, have_addr, count, modif)
277 	db_expr_t	addr;
278 	int		have_addr;
279 	db_expr_t	count;
280 	char *		modif;
281 {
282 	if (count == -1)
283 	    count = 1;
284 
285 	db_set_breakpoint(db_map_addr(addr), (db_addr_t)addr, count);
286 }
287 
288 /* list breakpoints */
289 /*ARGSUSED*/
290 void
291 db_listbreak_cmd(addr, have_addr, count, modif)
292 	db_expr_t	addr;
293 	int		have_addr;
294 	db_expr_t	count;
295 	char *		modif;
296 {
297 	db_list_breakpoints();
298 }
299 
300 #include <vm/vm_kern.h>
301 
302 /*
303  *	We want ddb to be usable before most of the kernel has been
304  *	initialized.  In particular, current_thread() or kernel_map
305  *	(or both) may be null.
306  */
307 
308 boolean_t
309 db_map_equal(map1, map2)
310 	vm_map_t	map1, map2;
311 {
312 	return ((map1 == map2) ||
313 		((map1 == NULL) && (map2 == kernel_map)) ||
314 		((map1 == kernel_map) && (map2 == NULL)));
315 }
316 
317 boolean_t
318 db_map_current(map)
319 	vm_map_t	map;
320 {
321 #if 0
322 	thread_t	thread;
323 
324 	return ((map == NULL) ||
325 		(map == kernel_map) ||
326 		(((thread = current_thread()) != NULL) &&
327 		 (map == thread->task->map)));
328 #else
329 	return (1);
330 #endif
331 }
332 
333 vm_map_t
334 db_map_addr(addr)
335 	vm_offset_t addr;
336 {
337 #if 0
338 	thread_t	thread;
339 
340 	/*
341 	 *	We want to return kernel_map for all
342 	 *	non-user addresses, even when debugging
343 	 *	kernel tasks with their own maps.
344 	 */
345 
346 	if ((VM_MIN_ADDRESS <= addr) &&
347 	    (addr < VM_MAX_ADDRESS) &&
348 	    ((thread = current_thread()) != NULL))
349 	    return thread->task->map;
350 	else
351 #endif
352 	    return kernel_map;
353 }
354