xref: /freebsd/sys/ddb/db_print.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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/param.h>
39 #include <sys/kdb.h>
40 #include <sys/proc.h>
41 
42 #include <machine/pcb.h>
43 
44 #include <ddb/ddb.h>
45 #include <ddb/db_variables.h>
46 #include <ddb/db_sym.h>
47 
48 void
49 db_show_regs(db_expr_t _1, bool _2, db_expr_t _3, char *modif)
50 {
51 	struct trapframe *oldtf;
52 	struct db_variable *regp;
53 	db_expr_t value, offset;
54 	const char *name;
55 
56 	/*
57 	 * The 'u' modifier instructs us to print the previous trapframe, most
58 	 * often containing state from userspace. This is done by temporarily
59 	 * switching out kdb_frame.
60 	 *
61 	 * NB: curthread is used instead of kdb_thread, so that behaviour is
62 	 * consistent with regular `show registers`, which always prints
63 	 * curthread's trapframe.
64 	 */
65 	oldtf = kdb_frame;
66 	if (modif[0] == 'u') {
67 		if (curthread->td_frame == NULL ||
68 		    curthread->td_frame == oldtf) {
69 			db_printf("previous trapframe unavailable");
70 			return;
71 		}
72 		kdb_frame = curthread->td_frame;
73 	}
74 
75 	for (regp = db_regs; regp < db_eregs; regp++) {
76 		if (!db_read_variable(regp, &value))
77 			continue;
78 		db_printf("%-12s%#*lr", regp->name,
79 		    (int)(sizeof(unsigned long) * 2 + 2), (unsigned long)value);
80 		db_find_xtrn_sym_and_offset((db_addr_t)value, &name, &offset);
81 		if (name != NULL && offset <= (unsigned long)db_maxoff &&
82 		    offset != value) {
83 			db_printf("\t%s", name);
84 			if (offset != 0)
85 				db_printf("+%+#lr", (long)offset);
86 		}
87 		db_printf("\n");
88 	}
89 	db_print_loc_and_inst(PC_REGS());
90 
91 	kdb_frame = oldtf;
92 }
93