xref: /openbsd/sys/ddb/db_output.c (revision 264ca280)
1 /*	$OpenBSD: db_output.c,v 1.29 2015/03/14 03:38:46 jsg 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/stdarg.h>
35 #include <sys/systm.h>
36 
37 #include <dev/cons.h>
38 
39 #include <machine/db_machdep.h>
40 
41 #include <ddb/db_command.h>
42 #include <ddb/db_output.h>
43 #include <ddb/db_interface.h>
44 #include <ddb/db_sym.h>
45 #include <ddb/db_var.h>
46 
47 /*
48  *	Character output - tracks position in line.
49  *	To do this correctly, we should know how wide
50  *	the output device is - then we could zero
51  *	the line position when the output device wraps
52  *	around to the start of the next line.
53  *
54  *	Instead, we count the number of spaces printed
55  *	since the last printing character so that we
56  *	don't print trailing spaces.  This avoids most
57  *	of the wraparounds.
58  */
59 
60 #ifndef	DB_MAX_LINE
61 #define	DB_MAX_LINE		24	/* maximum line */
62 #define DB_MAX_WIDTH		80	/* maximum width */
63 #endif	/* DB_MAX_LINE */
64 
65 #define DB_MIN_MAX_WIDTH	20	/* minimum max width */
66 #define DB_MIN_MAX_LINE		3	/* minimum max line */
67 #define CTRL(c)			((c) & 0xff)
68 
69 int	db_output_position = 0;		/* output column */
70 int	db_output_line = 0;		/* output line number */
71 int	db_last_non_space = 0;		/* last non-space character */
72 int	db_tab_stop_width = 8;		/* how wide are tab stops? */
73 #define	NEXT_TAB(i) \
74 	((((i) + db_tab_stop_width) / db_tab_stop_width) * db_tab_stop_width)
75 int	db_max_line = DB_MAX_LINE;	/* output max lines */
76 int	db_max_width = DB_MAX_WIDTH;	/* output line width */
77 int	db_radix = 16;			/* output numbers radix */
78 
79 static void db_more(void);
80 
81 /*
82  * Force pending whitespace.
83  */
84 void
85 db_force_whitespace(void)
86 {
87 	int last_print, next_tab;
88 
89 	last_print = db_last_non_space;
90 	while (last_print < db_output_position) {
91 	    next_tab = NEXT_TAB(last_print);
92 	    if (next_tab <= db_output_position) {
93 		while (last_print < next_tab) { /* DON'T send a tab!!! */
94 			cnputc(' ');
95 			last_print++;
96 		}
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 	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 
145 	if (c > ' ' && c <= '~') {
146 	    /*
147 	     * Printing character.
148 	     * If we have spaces to print, print them first.
149 	     * Use tabs if possible.
150 	     */
151 	    db_force_whitespace();
152 	    cnputc(c);
153 	    db_output_position++;
154 	    if (db_max_width >= DB_MIN_MAX_WIDTH
155 		&& db_output_position >= db_max_width-1) {
156 		/* auto new line */
157 		cnputc('\n');
158 		db_output_position = 0;
159 		db_last_non_space = 0;
160 		db_output_line++;
161 	    }
162 	    db_last_non_space = db_output_position;
163 	}
164 	else if (c == '\n') {
165 	    /* Return */
166 	    cnputc(c);
167 	    db_output_position = 0;
168 	    db_last_non_space = 0;
169 	    db_output_line++;
170 	}
171 	else if (c == '\t') {
172 	    /* assume tabs every 8 positions */
173 	    db_output_position = NEXT_TAB(db_output_position);
174 	}
175 	else if (c == ' ') {
176 	    /* space */
177 	    db_output_position++;
178 	}
179 	else if (c == '\007') {
180 	    /* bell */
181 	    cnputc(c);
182 	}
183 	/* other characters are assumed non-printing */
184 }
185 
186 /*
187  * Return output position
188  */
189 int
190 db_print_position(void)
191 {
192 	return (db_output_position);
193 }
194 
195 /*
196  * End line if too long.
197  */
198 void
199 db_end_line(int space)
200 {
201 	if (db_output_position >= db_max_width - space)
202 	    db_printf("\n");
203 }
204 
205 char *
206 db_format(char *buf, size_t bufsize, long val, int format, int alt, int width)
207 {
208 	const char *fmt;
209 
210 	if (format == DB_FORMAT_Z || db_radix == 16)
211 		fmt = alt ? "-%#*lx" : "-%*lx";
212 	else if (db_radix == 8)
213 		fmt = alt ? "-%#*lo" : "-%*lo";
214 	else
215 		fmt = alt ? "-%#*lu" : "-%*lu";
216 
217 	/* The leading '-' is a nasty (and beautiful) idea from NetBSD */
218 	if (val < 0 && format != DB_FORMAT_N)
219 		val = -val;
220 	else
221 		fmt++;
222 
223 	snprintf(buf, bufsize, fmt, width, val);
224 
225 	return (buf);
226 }
227 
228 void
229 db_stack_dump(void)
230 {
231 	static int intrace;
232 
233 	if (intrace) {
234 		printf("Faulted in traceback, aborting...\n");
235 		return;
236 	}
237 
238 	intrace = 1;
239 	printf("Starting stack trace...\n");
240 	db_stack_trace_print((db_expr_t)__builtin_frame_address(0), TRUE,
241 	    256 /* low limit */, "", printf);
242 	printf("End of stack trace.\n");
243 	intrace = 0;
244 }
245