xref: /freebsd/sys/ddb/db_output.c (revision 3642298923e528d795e3a30ec165d2b469e28b40)
1 /*-
2  * Mach Operating System
3  * Copyright (c) 1991,1990 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie the
24  * rights to redistribute these changes.
25  */
26 /*
27  * 	Author: David B. Golub, Carnegie Mellon University
28  *	Date:	7/90
29  */
30 
31 /*
32  * Printf and character output for debugger.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/cons.h>
41 #include <sys/kdb.h>
42 #include <sys/kernel.h>
43 #include <sys/sysctl.h>
44 
45 #include <machine/stdarg.h>
46 
47 #include <ddb/ddb.h>
48 #include <ddb/db_output.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 static int	db_output_position = 0;		/* output column */
63 static int	db_last_non_space = 0;		/* last non-space character */
64 db_expr_t	db_tab_stop_width = 8;		/* how wide are tab stops? */
65 #define	NEXT_TAB(i) \
66 	((((i) + db_tab_stop_width) / db_tab_stop_width) * db_tab_stop_width)
67 db_expr_t	db_max_width = 79;		/* output line width */
68 db_expr_t	db_lines_per_page = 20;		/* lines per page */
69 static int	db_newlines;			/* # lines this page */
70 static int	db_maxlines = -1;		/* max lines/page when paging */
71 static db_page_calloutfcn_t *db_page_callout = NULL;
72 static void	*db_page_callout_arg = NULL;
73 static int	ddb_use_printf = 0;
74 SYSCTL_INT(_debug, OID_AUTO, ddb_use_printf, CTLFLAG_RW, &ddb_use_printf, 0,
75     "use printf for all ddb output");
76 
77 static void	db_putchar(int c, void *arg);
78 
79 /*
80  * Force pending whitespace.
81  */
82 void
83 db_force_whitespace()
84 {
85 	register int last_print, next_tab;
86 
87 	last_print = db_last_non_space;
88 	while (last_print < db_output_position) {
89 	    next_tab = NEXT_TAB(last_print);
90 	    if (next_tab <= db_output_position) {
91 		while (last_print < next_tab) { /* DON'T send a tab!!! */
92 			cnputc(' ');
93 			last_print++;
94 		}
95 	    }
96 	    else {
97 		cnputc(' ');
98 		last_print++;
99 	    }
100 	}
101 	db_last_non_space = db_output_position;
102 }
103 
104 /*
105  * Output character.  Buffer whitespace.
106  */
107 static void
108 db_putchar(c, arg)
109 	int	c;		/* character to output */
110 	void *	arg;
111 {
112 
113 	/*
114 	 * If not in the debugger or the user requests it, output data to
115 	 * both the console and the message buffer.
116 	 */
117 	if (!kdb_active || ddb_use_printf) {
118 		printf("%c", c);
119 		if (!kdb_active)
120 			return;
121 		if (c == '\r' || c == '\n')
122 			db_check_interrupt();
123 		if (c == '\n' && db_maxlines > 0 && db_page_callout != NULL) {
124 			db_newlines++;
125 			if (db_newlines >= db_maxlines) {
126 				db_maxlines = -1;
127 				db_page_callout(db_page_callout_arg);
128 			}
129 		}
130 		return;
131 	}
132 
133 	/* Otherwise, output data directly to the console. */
134 	if (c > ' ' && c <= '~') {
135 	    /*
136 	     * Printing character.
137 	     * If we have spaces to print, print them first.
138 	     * Use tabs if possible.
139 	     */
140 	    db_force_whitespace();
141 	    cnputc(c);
142 	    db_output_position++;
143 	    db_last_non_space = db_output_position;
144 	}
145 	else if (c == '\n') {
146 	    /* Newline */
147 	    db_force_whitespace();
148 	    cnputc(c);
149 	    db_output_position = 0;
150 	    db_last_non_space = 0;
151 	    db_check_interrupt();
152 	    if (db_maxlines > 0 && db_page_callout != NULL) {
153 		    db_newlines++;
154 		    if (db_newlines >= db_maxlines) {
155 			    db_maxlines = -1;
156 			    db_page_callout(db_page_callout_arg);
157 		    }
158 	    }
159 	}
160 	else if (c == '\r') {
161 	    /* Return */
162 	    db_force_whitespace();
163 	    cnputc(c);
164 	    db_output_position = 0;
165 	    db_last_non_space = 0;
166 	    db_check_interrupt();
167 	}
168 	else if (c == '\t') {
169 	    /* assume tabs every 8 positions */
170 	    db_output_position = NEXT_TAB(db_output_position);
171 	}
172 	else if (c == ' ') {
173 	    /* space */
174 	    db_output_position++;
175 	}
176 	else if (c == '\007') {
177 	    /* bell */
178 	    cnputc(c);
179 	}
180 	/* other characters are assumed non-printing */
181 }
182 
183 /*
184  * Register callout for providing a pager for output.
185  */
186 void
187 db_setup_paging(db_page_calloutfcn_t *callout, void *arg, int maxlines)
188 {
189 
190 	db_page_callout = callout;
191 	db_page_callout_arg = arg;
192 	db_maxlines = maxlines;
193 	db_newlines = 0;
194 }
195 
196 /*
197  * A simple paging callout function.  If the argument is not null, it
198  * points to an integer that will be set to 1 if the user asks to quit.
199  */
200 void
201 db_simple_pager(void *arg)
202 {
203 	int c, done;
204 
205 	db_printf("--More--\r");
206 	done = 0;
207 	while (!done) {
208 		c = cngetc();
209 		switch (c) {
210 		case 'e':
211 		case 'j':
212 		case '\n':
213 			/* Just one more line. */
214 			db_setup_paging(db_simple_pager, arg, 1);
215 			done++;
216 			break;
217 		case 'd':
218 			/* Half a page. */
219 			db_setup_paging(db_simple_pager, arg,
220 			    db_lines_per_page / 2);
221 			done++;
222 			break;
223 		case 'f':
224 		case ' ':
225 			/* Another page. */
226 			db_setup_paging(db_simple_pager, arg,
227 			    db_lines_per_page);
228 			done++;
229 			break;
230 		case 'q':
231 		case 'Q':
232 		case 'x':
233 		case 'X':
234 			/* Quit */
235 			if (arg != NULL) {
236 				*(int *)arg = 1;
237 				done++;
238 				break;
239 			}
240 #if 0
241 			/* FALLTHROUGH */
242 		default:
243 			cnputc('\007');
244 #endif
245 		}
246 	}
247 	db_printf("        \r");
248 }
249 
250 /*
251  * Return output position
252  */
253 int
254 db_print_position()
255 {
256 	return (db_output_position);
257 }
258 
259 /*
260  * Printing
261  */
262 void
263 #if __STDC__
264 db_printf(const char *fmt, ...)
265 #else
266 db_printf(fmt)
267 	const char *fmt;
268 #endif
269 {
270 	va_list	listp;
271 
272 	va_start(listp, fmt);
273 	kvprintf (fmt, db_putchar, NULL, db_radix, listp);
274 	va_end(listp);
275 }
276 
277 int db_indent;
278 
279 void
280 #if __STDC__
281 db_iprintf(const char *fmt,...)
282 #else
283 db_iprintf(fmt)
284 	const char *fmt;
285 #endif
286 {
287 	register int i;
288 	va_list listp;
289 
290 	for (i = db_indent; i >= 8; i -= 8)
291 		db_printf("\t");
292 	while (--i >= 0)
293 		db_printf(" ");
294 	va_start(listp, fmt);
295 	kvprintf (fmt, db_putchar, NULL, db_radix, listp);
296 	va_end(listp);
297 }
298 
299 /*
300  * End line if too long.
301  */
302 void
303 db_end_line()
304 {
305 	if (db_output_position >= db_max_width)
306 	    db_printf("\n");
307 }
308