1/* $NetBSD: db_output.c,v 1.33 2012/09/01 01:13:51 matt 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
29/*
30 * Printf and character output for debugger.
31 */
32
33#ifdef _KERNEL_OPT
34#include "opt_ddbparam.h"
35#endif
36
37#include <sys/cdefs.h>
38__KERNEL_RCSID(0, "$NetBSD: db_output.c,v 1.33 2012/09/01 01:13:51 matt Exp $");
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/stdarg.h>
43
44#include <dev/cons.h>
45
46#include <ddb/ddb.h>
47
48/*
49 * Character output - tracks position in line.
50 * To do this correctly, we should know how wide
51 * the output device is - then we could zero
52 * the line position when the output device wraps
53 * around to the start of the next line.
54 *
55 * Instead, we count the number of spaces printed
56 * since the last printing character so that we
57 * don't print trailing spaces. This avoids most
58 * of the wraparounds.
59 */
60
61#ifndef DB_MAX_LINE
62#define DB_MAX_LINE 24 /* maximum line */
63#endif /* DB_MAX_LINE */
64#ifndef DB_MAX_WIDTH
65#define DB_MAX_WIDTH 80 /* maximum width */
66#endif /* DB_MAX_WIDTH */
67
68#define DB_MIN_MAX_WIDTH 20 /* minimum max width */
69#define DB_MIN_MAX_LINE 3 /* minimum max line */
70#define CTRL(c) ((c) & 0xff)
71
72int db_output_line = 0; /* output line number */
73int db_tab_stop_width = 8; /* how wide are tab stops? */
74int db_max_line = DB_MAX_LINE; /* output max lines */
75int db_max_width = DB_MAX_WIDTH; /* output line width */
76
77static int db_output_position = 0; /* output column */
78static int db_last_non_space = 0; /* last non-space character */
79
80static void db_more(void);
81
82/*
83 * Force pending whitespace.
84 */
85void
86db_force_whitespace(void)
87{
88 int last_print, next_tab;
89
90 last_print = db_last_non_space;
91 while (last_print < db_output_position) {
92 next_tab = DB_NEXT_TAB(last_print);
93 if (next_tab <= db_output_position) {
94 while (last_print < next_tab) { /* DON'T send a tab!! */
95 cnputc(' ');
96 last_print++;
97 }
98 } else {
99 cnputc(' ');
100 last_print++;
101 }
102 }
103 db_last_non_space = db_output_position;
104}
105
106static void
107db_more(void)
108{
109 const char *p;
110 int quit_output = 0;
111
112 for (p = "--db_more--"; *p; p++)
113 cnputc(*p);
114 switch(cngetc()) {
115 case ' ':
116 db_output_line = 0;
117 break;
118 case 'q':
119 case CTRL('c'):
120 db_output_line = 0;
121 quit_output = 1;
122 break;
123 default:
124 db_output_line--;
125 break;
126 }
127 p = "\b\b\b\b\b\b\b\b\b\b\b \b\b\b\b\b\b\b\b\b\b\b";
128 while (*p)
129 cnputc(*p++);
130 if (quit_output) {
131 db_error(0);
132 /* NOTREACHED */
133 }
134}
135
136/*
137 * Output character. Buffer whitespace.
138 */
139void
140db_putchar(int c)
141{
142 if (db_max_line >= DB_MIN_MAX_LINE && db_output_line >= db_max_line-1)
143 db_more();
144 if (c > ' ' && c <= '~') {
145 /*
146 * Printing character.
147 * If we have spaces to print, print them first.
148 * Use tabs if possible.
149 */
150 db_force_whitespace();
151 cnputc(c);
152 db_output_position++;
153 if (db_max_width >= DB_MIN_MAX_WIDTH
154 && db_output_position >= db_max_width) {
155 /* auto new line */
156 cnputc('\n');
157 db_output_position = 0;
158 db_last_non_space = 0;
159 db_output_line++;
160 }
161 db_last_non_space = db_output_position;
162 } else if (c == '\n') {
163 /* Return */
164 cnputc(c);
165 db_output_position = 0;
166 db_last_non_space = 0;
167 db_output_line++;
168 db_check_interrupt();
169 } else if (c == '\t') {
170 /* assume tabs every 8 positions */
171 db_output_position = DB_NEXT_TAB(db_output_position);
172 } else if (c == ' ') {
173 /* space */
174 db_output_position++;
175 } else if (c == '\007') {
176 /* bell */
177 cnputc(c);
178 }
179 /* other characters are assumed non-printing */
180}
181
182/*
183 * Return output position
184 */
185int
186db_print_position(void)
187{
188
189 return (db_output_position);
190}
191
192/*
193 * End line if too long.
194 */
195void
196db_end_line(void)
197{
198
199 if (db_output_position >= db_max_width)
200 db_printf("\n");
201}
202
203/*
204 * Replacement for old '%r' kprintf format.
205 */
206void
207db_format_radix(char *buf, size_t bufsiz, quad_t val, int altflag)
208{
209 const char *fmt;
210
211 if (db_radix == 16) {
212 db_format_hex(buf, bufsiz, val, altflag);
213 return;
214 }
215
216 if (db_radix == 8)
217 fmt = altflag ? "-%#qo" : "-%qo";
218 else
219 fmt = altflag ? "-%#qu" : "-%qu";
220
221 if (val < 0)
222 val = -val;
223 else
224 ++fmt;
225
226 snprintf(buf, bufsiz, fmt, val);
227}
228
229/*
230 * Replacement for old '%z' kprintf format.
231 */
232void
233db_format_hex(char *buf, size_t bufsiz, quad_t val, int altflag)
234{
235 /* Only use alternate form if val is nonzero. */
236 const char *fmt = (altflag && val) ? "-%#qx" : "-%qx";
237
238 if (val < 0)
239 val = -val;
240 else
241 ++fmt;
242
243 snprintf(buf, bufsiz, fmt, val);
244}
245