xref: /netbsd/sys/ddb/db_trap.c (revision 5dbbc1a3)
1 /*	$NetBSD: db_trap.c,v 1.26 2019/03/12 07:44:58 skrll 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 "AS IS"
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  * Trap entry point to kernel debugger.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: db_trap.c,v 1.26 2019/03/12 07:44:58 skrll Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/proc.h>
41 
42 #include <machine/db_machdep.h>
43 
44 #include <ddb/db_run.h>
45 #include <ddb/db_command.h>
46 #include <ddb/db_break.h>
47 #include <ddb/db_output.h>
48 #include <ddb/db_sym.h>
49 #include <ddb/db_extern.h>
50 
51 /*
52  * db_trap_callback can be hooked by MD port code to handle special
53  * cases such as disabling hardware watchdogs while in DDB.
54  */
55 void (*db_trap_callback)(int);
56 
57 int db_trap_type;
58 
59 void
db_trap(int type,int code)60 db_trap(int type, int code)
61 {
62 	bool	bkpt;
63 	bool	watchpt;
64 
65 	db_trap_type = type;
66 
67 	bkpt = IS_BREAKPOINT_TRAP(type, code);
68 	watchpt = IS_WATCHPOINT_TRAP(type, code);
69 
70 	if (db_trap_callback)
71 		db_trap_callback(1);
72 
73 	if (db_stop_at_pc(DDB_REGS, &bkpt)) {
74 		if (db_inst_count) {
75 			db_printf("After %d instructions "
76 			    "(%d loads, %d stores),\n",
77 			    db_inst_count, db_load_count, db_store_count);
78 		}
79 		if (bkpt)
80 			db_printf("Breakpoint");
81 		else if (watchpt)
82 			db_printf("Watchpoint");
83 		else
84 			db_printf("Stopped");
85 		db_printf(" in pid %d.%d (%s) at\t",
86 		    curproc->p_pid, curlwp->l_lid,
87 		    curproc->p_comm);
88 		db_dot = PC_REGS(DDB_REGS);
89 		db_print_loc_and_inst(db_dot);
90 
91 		db_command_loop();
92 	}
93 
94 	db_restart_at_pc(DDB_REGS, watchpt);
95 
96 	if (db_trap_callback)
97 		db_trap_callback(0);
98 }
99