xref: /openbsd/sys/ddb/db_output.c (revision fb6263dd)
1 /*	$OpenBSD: db_output.c,v 1.37 2021/06/10 12:33:48 bluhm Exp $	*/
2 /*	$NetBSD: db_output.c,v 1.13 1996/04/01 17:27:14 christos Exp $	*/
3 
4 /*
5  * Mach Operating System
6  * Copyright (c) 1993,1992,1991,1990 Carnegie Mellon University
7  * All Rights Reserved.
8  *
9  * Permission to use, copy, modify and distribute this software and its
10  * documentation is hereby granted, provided that both the copyright
11  * notice and this permission notice appear in all copies of the
12  * software, derivative works or modified versions, and any portions
13  * thereof, and that both notices appear in supporting documentation.
14  *
15  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
17  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18  *
19  * Carnegie Mellon requests users of this software to return to
20  *
21  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22  *  School of Computer Science
23  *  Carnegie Mellon University
24  *  Pittsburgh PA 15213-3890
25  *
26  * any improvements or extensions that they make and grant Carnegie Mellon
27  * the rights to redistribute these changes.
28  */
29 
30 /*
31  * Printf and character output for debugger.
32  */
33 #include <sys/param.h>
34 #include <sys/atomic.h>
35 #include <sys/stdarg.h>
36 #include <sys/systm.h>
37 #include <sys/stacktrace.h>
38 
39 #include <dev/cons.h>
40 
41 #include <machine/db_machdep.h>
42 
43 #include <ddb/db_command.h>
44 #include <ddb/db_output.h>
45 #include <ddb/db_access.h>
46 #include <ddb/db_interface.h>
47 #include <ddb/db_sym.h>
48 #include <ddb/db_var.h>
49 
50 /*
51  *	Character output - tracks position in line.
52  *	To do this correctly, we should know how wide
53  *	the output device is - then we could zero
54  *	the line position when the output device wraps
55  *	around to the start of the next line.
56  *
57  *	Instead, we count the number of spaces printed
58  *	since the last printing character so that we
59  *	don't print trailing spaces.  This avoids most
60  *	of the wraparounds.
61  */
62 
63 #ifndef	DB_MAX_LINE
64 #define	DB_MAX_LINE		24	/* maximum line */
65 #define DB_MAX_WIDTH		80	/* maximum width */
66 #endif	/* DB_MAX_LINE */
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_position = 0;		/* output column */
73 int	db_output_line = 0;		/* output line number */
74 int	db_last_non_space = 0;		/* last non-space character */
75 int	db_tab_stop_width = 8;		/* how wide are tab stops? */
76 #define	NEXT_TAB(i) \
77 	((((i) + db_tab_stop_width) / db_tab_stop_width) * db_tab_stop_width)
78 int	db_max_line = DB_MAX_LINE;	/* output max lines */
79 int	db_max_width = DB_MAX_WIDTH;	/* output line width */
80 int	db_radix = 16;			/* output numbers radix */
81 
82 static void db_more(void);
83 
84 /*
85  * Force pending whitespace.
86  */
87 void
db_force_whitespace(void)88 db_force_whitespace(void)
89 {
90 	int last_print, next_tab;
91 
92 	last_print = db_last_non_space;
93 	while (last_print < db_output_position) {
94 		next_tab = NEXT_TAB(last_print);
95 		if (next_tab <= db_output_position) {
96 			while (last_print < next_tab) { /* DON'T send a tab!!! */
97 				cnputc(' ');
98 				last_print++;
99 			}
100 		} else {
101 			cnputc(' ');
102 			last_print++;
103 		}
104 	}
105 	db_last_non_space = db_output_position;
106 }
107 
108 static void
db_more(void)109 db_more(void)
110 {
111 	char *p;
112 	int quit_output = 0;
113 
114 	for (p = "--db_more--"; *p; p++)
115 		cnputc(*p);
116 	switch(cngetc()) {
117 	case ' ':
118 		db_output_line = 0;
119 		break;
120 	case 'q':
121 	case CTRL('c'):
122 		db_output_line = 0;
123 		quit_output = 1;
124 		break;
125 	default:
126 		db_output_line--;
127 		break;
128 	}
129 	p = "\b\b\b\b\b\b\b\b\b\b\b           \b\b\b\b\b\b\b\b\b\b\b";
130 	while (*p)
131 		cnputc(*p++);
132 	if (quit_output) {
133 		db_error(0);
134 		/* NOTREACHED */
135 	}
136 }
137 
138 /*
139  * Output character.  Buffer whitespace.
140  */
141 void
db_putchar(int c)142 db_putchar(int c)
143 {
144 	if (db_max_line >= DB_MIN_MAX_LINE && db_output_line >= db_max_line-1)
145 		db_more();
146 
147 	if (c > ' ' && c <= '~') {
148 		/*
149 		 * Printing character.
150 		 * If we have spaces to print, print them first.
151 		 * Use tabs if possible.
152 		 */
153 		db_force_whitespace();
154 		cnputc(c);
155 		db_output_position++;
156 		if (db_max_width >= DB_MIN_MAX_WIDTH &&
157 		    db_output_position >= db_max_width-1) {
158 			/* auto new line */
159 			cnputc('\n');
160 			db_output_position = 0;
161 			db_last_non_space = 0;
162 			db_output_line++;
163 		}
164 		db_last_non_space = db_output_position;
165 	} else if (c == '\n') {
166 		/* Return */
167 		cnputc(c);
168 		db_output_position = 0;
169 		db_last_non_space = 0;
170 		db_output_line++;
171 	} else if (c == '\t') {
172 		/* assume tabs every 8 positions */
173 		db_output_position = NEXT_TAB(db_output_position);
174 	} else if (c == ' ') {
175 		/* space */
176 		db_output_position++;
177 	} else if (c == '\007') {
178 		/* bell */
179 		cnputc(c);
180 	}
181 	/* other characters are assumed non-printing */
182 }
183 
184 /*
185  * Return output position
186  */
187 int
db_print_position(void)188 db_print_position(void)
189 {
190 	return (db_output_position);
191 }
192 
193 /*
194  * End line if too long.
195  */
196 void
db_end_line(int space)197 db_end_line(int space)
198 {
199 	if (db_output_position >= db_max_width - space)
200 		db_printf("\n");
201 }
202 
203 char *
db_format(char * buf,size_t bufsize,long val,int format,int alt,int width)204 db_format(char *buf, size_t bufsize, long val, int format, int alt, int width)
205 {
206 	const char *fmt;
207 
208 	if (format == DB_FORMAT_Z || db_radix == 16)
209 		fmt = alt ? "-%#*lx" : "-%*lx";
210 	else if (db_radix == 8)
211 		fmt = alt ? "-%#*lo" : "-%*lo";
212 	else
213 		fmt = alt ? "-%#*lu" : "-%*lu";
214 
215 	/* The leading '-' is a nasty (and beautiful) idea from NetBSD */
216 	if (val < 0 && format != DB_FORMAT_N)
217 		val = -val;
218 	else
219 		fmt++;
220 
221 	snprintf(buf, bufsize, fmt, width, val);
222 	return (buf);
223 }
224 
225 void
db_stack_dump(void)226 db_stack_dump(void)
227 {
228 	static struct cpu_info *intrace = NULL;
229 	struct cpu_info *tracing, *ci = curcpu();
230 
231 	tracing = atomic_cas_ptr(&intrace, NULL, ci);
232 	if (tracing != NULL) {
233 		if (tracing == ci)
234 			printf("Faulted in traceback, aborting...\n");
235 		else
236 			printf("Parallel traceback, suppressed...\n");
237 		return;
238 	}
239 
240 	printf("Starting stack trace...\n");
241 	db_stack_trace_print((db_expr_t)__builtin_frame_address(0), 1,
242 	    256 /* low limit */, "", printf);
243 	printf("End of stack trace.\n");
244 	membar_producer();
245 	intrace = NULL;
246 }
247 
248 void
stacktrace_print(struct stacktrace * st,int (* pr)(const char *,...))249 stacktrace_print(struct stacktrace *st, int (*pr)(const char *, ...))
250 {
251 	unsigned int i;
252 
253 	for (i = 0; i < st->st_count; i++) {
254 		(*pr)("#%-2u ", i);
255 		db_printsym(st->st_pc[i], DB_STGY_PROC, pr);
256 		(*pr)("\n");
257 	}
258 	if (st->st_count == 0)
259 		(*pr)("<empty stack trace>\n");
260 }
261 
262 void
db_resize(int cols,int rows)263 db_resize(int cols, int rows)
264 {
265 	db_max_width = cols;
266 	db_max_line = rows;
267 }
268