1 /* $NetBSD: db_output.c,v 1.38 2023/10/07 20:22:53 ad 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 1.38 2023/10/07 20:22:53 ad Exp $");
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/stdarg.h>
43 #include <sys/time.h>
44
45 #include <dev/cons.h>
46
47 #include <ddb/ddb.h>
48
49 /*
50 * Character output - tracks position in line.
51 * To do this correctly, we should know how wide
52 * the output device is - then we could zero
53 * the line position when the output device wraps
54 * around to the start of the next line.
55 *
56 * Instead, we count the number of spaces printed
57 * since the last printing character so that we
58 * don't print trailing spaces. This avoids most
59 * of the wraparounds.
60 */
61
62 #ifndef DB_MAX_LINE
63 #define DB_MAX_LINE 24 /* maximum line */
64 #endif /* DB_MAX_LINE */
65 #ifndef DB_MAX_WIDTH
66 #define DB_MAX_WIDTH 80 /* maximum width */
67 #endif /* DB_MAX_WIDTH */
68
69 #define DB_MIN_MAX_WIDTH 20 /* minimum max width */
70 #define DB_MIN_MAX_LINE 3 /* minimum max line */
71 #define CTRL(c) ((c) & 0xff)
72
73 int db_output_line = 0; /* output line number */
74 int db_tab_stop_width = 8; /* how wide are tab stops? */
75 int db_max_line = DB_MAX_LINE; /* output max lines */
76 int db_max_width = DB_MAX_WIDTH; /* output line width */
77
78 static int db_output_position = 0; /* output column */
79 static int db_last_non_space = 0; /* last non-space character */
80
81 static void db_more(void);
82
83 /*
84 * Force pending whitespace.
85 */
86 void
db_force_whitespace(void)87 db_force_whitespace(void)
88 {
89 int last_print, next_tab;
90
91 last_print = db_last_non_space;
92 while (last_print < db_output_position) {
93 next_tab = DB_NEXT_TAB(last_print);
94 if (next_tab <= db_output_position) {
95 while (last_print < next_tab) { /* DON'T send a tab!! */
96 cnputc(' ');
97 last_print++;
98 }
99 } else {
100 cnputc(' ');
101 last_print++;
102 }
103 }
104 db_last_non_space = db_output_position;
105 }
106
107
108 /*
109 * End the current line if it exceeds $maxwidth
110 */
111 static void
db_check_wrap(void)112 db_check_wrap(void)
113 {
114
115 if (db_max_width >= DB_MIN_MAX_WIDTH
116 && db_output_position >= db_max_width) {
117 cnputc('\n');
118 db_output_position = 0;
119 db_last_non_space = 0;
120 db_output_line++;
121 }
122 }
123
124
125 static void
db_more(void)126 db_more(void)
127 {
128 const char *p;
129 int quit_output = 0;
130
131 for (p = "--db_more--"; *p; p++)
132 cnputc(*p);
133 switch (cngetc()) {
134 case ' ':
135 db_output_line = 0;
136 break;
137 case 'q':
138 case CTRL('c'):
139 db_output_line = 0;
140 quit_output = 1;
141 break;
142 default:
143 db_output_line--;
144 break;
145 }
146 p = "\b\b\b\b\b\b\b\b\b\b\b \b\b\b\b\b\b\b\b\b\b\b";
147 while (*p)
148 cnputc(*p++);
149 if (quit_output) {
150 db_error(0);
151 /* NOTREACHED */
152 }
153 }
154
155 /*
156 * Output character. Buffer whitespace.
157 */
158 void
db_putchar(int c)159 db_putchar(int c)
160 {
161 if (db_max_line >= DB_MIN_MAX_LINE && db_output_line >= db_max_line-1)
162 db_more();
163 if (c > ' ' && c <= '~') {
164 /*
165 * Printing character.
166 * If we have spaces to print, print them first.
167 * Use tabs if possible.
168 */
169 db_force_whitespace();
170 db_check_wrap();
171 cnputc(c);
172 db_output_position++;
173 db_check_wrap();
174 db_last_non_space = db_output_position;
175 } else if (c == '\n') {
176 /* Return */
177 cnputc(c);
178 db_output_position = 0;
179 db_last_non_space = 0;
180 db_output_line++;
181 db_check_interrupt();
182 } else if (c == '\t') {
183 /* assume tabs every 8 positions */
184 db_output_position = DB_NEXT_TAB(db_output_position);
185 } else if (c == ' ') {
186 /* space */
187 db_output_position++;
188 } else if (c == '\007') {
189 /* bell */
190 cnputc(c);
191 }
192 /* other characters are assumed non-printing */
193 }
194
195 /*
196 * Return output position
197 */
198 int
db_print_position(void)199 db_print_position(void)
200 {
201
202 return (db_output_position);
203 }
204
205 /*
206 * End line if too long.
207 */
208 void
db_end_line(void)209 db_end_line(void)
210 {
211
212 if (db_output_position >= db_max_width)
213 db_printf("\n");
214 }
215
216 /*
217 * Replacement for old '%r' kprintf format.
218 */
219 void
db_format_radix(char * buf,size_t bufsiz,quad_t val,int altflag)220 db_format_radix(char *buf, size_t bufsiz, quad_t val, int altflag)
221 {
222 const char *fmt;
223
224 if (db_radix == 16) {
225 db_format_hex(buf, bufsiz, val, altflag);
226 return;
227 }
228
229 if (db_radix == 8)
230 fmt = altflag ? "-%#qo" : "-%qo";
231 else
232 fmt = altflag ? "-%#qu" : "-%qu";
233
234 if (val < 0)
235 val = -val;
236 else
237 ++fmt;
238
239 snprintf(buf, bufsiz, fmt, val);
240 }
241
242 /*
243 * Replacement for old '%z' kprintf format.
244 */
245 void
db_format_hex(char * buf,size_t bufsiz,quad_t val,int altflag)246 db_format_hex(char *buf, size_t bufsiz, quad_t val, int altflag)
247 {
248 /* Only use alternate form if val is nonzero. */
249 const char *fmt = (altflag && val) ? "-%#qx" : "-%qx";
250
251 if (val < 0)
252 val = -val;
253 else
254 ++fmt;
255
256 snprintf(buf, bufsiz, fmt, val);
257 }
258
259 /*
260 * Print out a timespec value.
261 */
262 void
db_print_timespec(struct timespec * ts)263 db_print_timespec(struct timespec *ts)
264 {
265
266 db_printf("%" PRIu64 ".%09ld", (uint64_t)ts->tv_sec, ts->tv_nsec);
267 }
268