xref: /freebsd/sys/ddb/db_print.c (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
1 /*-
2  * SPDX-License-Identifier: MIT-CMU
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 /*
30  *	Author: David B. Golub, Carnegie Mellon University
31  *	Date:	7/90
32  */
33 
34 /*
35  * Miscellaneous printing.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <sys/param.h>
42 #include <sys/kdb.h>
43 #include <sys/proc.h>
44 
45 #include <machine/pcb.h>
46 
47 #include <ddb/ddb.h>
48 #include <ddb/db_variables.h>
49 #include <ddb/db_sym.h>
50 
51 void
52 db_show_regs(db_expr_t _1, bool _2, db_expr_t _3, char *modif)
53 {
54 	struct trapframe *oldtf;
55 	struct db_variable *regp;
56 	db_expr_t value, offset;
57 	const char *name;
58 
59 	/*
60 	 * The 'u' modifier instructs us to print the previous trapframe, most
61 	 * often containing state from userspace. This is done by temporarily
62 	 * switching out kdb_frame.
63 	 *
64 	 * NB: curthread is used instead of kdb_thread, so that behaviour is
65 	 * consistent with regular `show registers`, which always prints
66 	 * curthread's trapframe.
67 	 */
68 	oldtf = kdb_frame;
69 	if (modif[0] == 'u') {
70 		if (curthread->td_frame == NULL ||
71 		    curthread->td_frame == oldtf) {
72 			db_printf("previous trapframe unavailable");
73 			return;
74 		}
75 		kdb_frame = curthread->td_frame;
76 	}
77 
78 	for (regp = db_regs; regp < db_eregs; regp++) {
79 		if (!db_read_variable(regp, &value))
80 			continue;
81 		db_printf("%-12s%#*lr", regp->name,
82 		    (int)(sizeof(unsigned long) * 2 + 2), (unsigned long)value);
83 		db_find_xtrn_sym_and_offset((db_addr_t)value, &name, &offset);
84 		if (name != NULL && offset <= (unsigned long)db_maxoff &&
85 		    offset != value) {
86 			db_printf("\t%s", name);
87 			if (offset != 0)
88 				db_printf("+%+#lr", (long)offset);
89 		}
90 		db_printf("\n");
91 	}
92 	db_print_loc_and_inst(PC_REGS());
93 
94 	kdb_frame = oldtf;
95 }
96