xref: /netbsd-src/sys/ddb/db_output.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
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 
72 int	db_output_line = 0;			/* output line number */
73 int	db_tab_stop_width = 8;			/* how wide are tab stops? */
74 int	db_max_line = DB_MAX_LINE;		/* output max lines */
75 int	db_max_width = DB_MAX_WIDTH;		/* output line width */
76 
77 static int	db_output_position = 0;		/* output column */
78 static int	db_last_non_space = 0;		/* last non-space character */
79 
80 static void db_more(void);
81 
82 /*
83  * Force pending whitespace.
84  */
85 void
86 db_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 
106 static void
107 db_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  */
139 void
140 db_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  */
185 int
186 db_print_position(void)
187 {
188 
189 	return (db_output_position);
190 }
191 
192 /*
193  * End line if too long.
194  */
195 void
196 db_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  */
206 void
207 db_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  */
232 void
233 db_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