xref: /netbsd-src/sys/ddb/db_sym.c (revision ce63d6c20fc4ec8ddc95c84bb229e3c4ecf82b69)
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  * $Id: db_sym.c,v 1.2 1993/05/20 03:39:31 cgd Exp $
28  *
29  * HISTORY
30  * $Log: db_sym.c,v $
31  * Revision 1.2  1993/05/20 03:39:31  cgd
32  * add explicit rcs id
33  *
34  * Revision 1.1.1.1  1993/03/21  09:46:27  cgd
35  * initial import of 386bsd-0.1 sources
36  *
37  * Revision 1.1  1992/03/25  21:45:27  pace
38  * Initial revision
39  *
40  * Revision 2.5  91/02/05  17:07:07  mrt
41  * 	Changed to new Mach copyright
42  * 	[91/01/31  16:19:17  mrt]
43  *
44  * Revision 2.4  90/10/25  14:44:05  rwd
45  * 	Changed db_printsym to print unsigned.
46  * 	[90/10/19            rpd]
47  *
48  * Revision 2.3  90/09/09  23:19:56  rpd
49  * 	Avoid totally incorrect guesses of symbol names for small values.
50  * 	[90/08/30  17:39:48  af]
51  *
52  * Revision 2.2  90/08/27  21:52:18  dbg
53  * 	Removed nlist.h.  Fixed some type declarations.
54  * 	Qualifier character is ':'.
55  * 	[90/08/20            dbg]
56  * 	Modularized symtab info into a new db_symtab_t type.
57  * 	Modified db_add_symbol_table  and others accordingly.
58  * 	Defined db_sym_t, a new (opaque) type used to represent
59  * 	symbols.  This should support all sort of future symtable
60  * 	formats. Functions like db_qualify take a db_sym_t now.
61  * 	New db_symbol_values() function to explode the content
62  * 	of a db_sym_t.
63  * 	db_search_symbol() replaces db_find_sym_and_offset(), which is
64  * 	now a macro defined in our (new) header file.  This new
65  * 	function accepts more restrictive searches, which are
66  * 	entirely delegated to the symtab-specific code.
67  * 	Accordingly, db_printsym() accepts a strategy parameter.
68  * 	New db_line_at_pc() function.
69  * 	Renamed misleading db_eqsym into db_eqname.
70  * 	[90/08/20  10:47:06  af]
71  *
72  * 	Created.
73  * 	[90/07/25            dbg]
74  *
75  * Revision 2.1  90/07/26  16:43:52  dbg
76  * Created.
77  *
78  */
79 /*
80  * 	Author: David B. Golub, Carnegie Mellon University
81  *	Date:	7/90
82  */
83 #include "param.h"
84 #include "proc.h"
85 #include <machine/db_machdep.h>
86 #include <ddb/db_sym.h>
87 
88 /*
89  * We import from the symbol-table dependent routines:
90  */
91 extern db_sym_t	X_db_lookup();
92 extern db_sym_t	X_db_search_symbol();
93 extern boolean_t X_db_line_at_pc();
94 extern void	X_db_symbol_values();
95 
96 /*
97  * Multiple symbol tables
98  */
99 #define	MAXNOSYMTABS	3	/* mach, ux, emulator */
100 
101 db_symtab_t	db_symtabs[MAXNOSYMTABS] = {{0,},};
102 int db_nsymtab = 0;
103 
104 db_symtab_t	*db_last_symtab;
105 
106 db_sym_t	db_lookup();	/* forward */
107 
108 /*
109  * Add symbol table, with given name, to list of symbol tables.
110  */
111 void
112 db_add_symbol_table(start, end, name, ref)
113 	char *start;
114 	char *end;
115 	char *name;
116 	char *ref;
117 {
118 	if (db_nsymtab >= MAXNOSYMTABS) {
119 		printf ("No slots left for %s symbol table", name);
120 		panic ("db_sym.c: db_add_symbol_table");
121 	}
122 
123 	db_symtabs[db_nsymtab].start = start;
124 	db_symtabs[db_nsymtab].end = end;
125 	db_symtabs[db_nsymtab].name = name;
126 	db_symtabs[db_nsymtab].private = ref;
127 	db_nsymtab++;
128 }
129 
130 /*
131  *  db_qualify("vm_map", "ux") returns "unix:vm_map".
132  *
133  *  Note: return value points to static data whose content is
134  *  overwritten by each call... but in practice this seems okay.
135  */
136 static char *
137 db_qualify(sym, symtabname)
138 	db_sym_t	sym;
139 	register char	*symtabname;
140 {
141 	char		*symname;
142 	static char     tmp[256];
143 	register char	*s;
144 
145 	db_symbol_values(sym, &symname, 0);
146 	s = tmp;
147 	while (*s++ = *symtabname++) {
148 	}
149 	s[-1] = ':';
150 	while (*s++ = *symname++) {
151 	}
152 	return tmp;
153 }
154 
155 
156 boolean_t
157 db_eqname(src, dst, c)
158 	char *src;
159 	char *dst;
160 	char c;
161 {
162 	if (!strcmp(src, dst))
163 	    return (TRUE);
164 	if (src[0] == c)
165 	    return (!strcmp(src+1,dst));
166 	return (FALSE);
167 }
168 
169 boolean_t
170 db_value_of_name(name, valuep)
171 	char		*name;
172 	db_expr_t	*valuep;
173 {
174 	db_sym_t	sym;
175 
176 	sym = db_lookup(name);
177 	if (sym == DB_SYM_NULL)
178 	    return (FALSE);
179 	db_symbol_values(sym, &name, valuep);
180 	return (TRUE);
181 }
182 
183 
184 /*
185  * Lookup a symbol.
186  * If the symbol has a qualifier (e.g., ux:vm_map),
187  * then only the specified symbol table will be searched;
188  * otherwise, all symbol tables will be searched.
189  */
190 db_sym_t
191 db_lookup(symstr)
192 	char *symstr;
193 {
194 	db_sym_t sp;
195 	register int i;
196 	int symtab_start = 0;
197 	int symtab_end = db_nsymtab;
198 	register char *cp;
199 
200 	/*
201 	 * Look for, remove, and remember any symbol table specifier.
202 	 */
203 	for (cp = symstr; *cp; cp++) {
204 		if (*cp == ':') {
205 			*cp = '\0';
206 			for (i = 0; i < db_nsymtab; i++) {
207 				if (! strcmp(symstr, db_symtabs[i].name)) {
208 					symtab_start = i;
209 					symtab_end = i + 1;
210 					break;
211 				}
212 			}
213 			*cp = ':';
214 			if (i == db_nsymtab) {
215 				db_error("invalid symbol table name");
216 			}
217 			symstr = cp+1;
218 		}
219 	}
220 
221 	/*
222 	 * Look in the specified set of symbol tables.
223 	 * Return on first match.
224 	 */
225 	for (i = symtab_start; i < symtab_end; i++) {
226 		if (sp = X_db_lookup(&db_symtabs[i], symstr)) {
227 			db_last_symtab = &db_symtabs[i];
228 			return sp;
229 		}
230 	}
231 	return 0;
232 }
233 
234 /*
235  * Does this symbol name appear in more than one symbol table?
236  * Used by db_symbol_values to decide whether to qualify a symbol.
237  */
238 boolean_t db_qualify_ambiguous_names = FALSE;
239 
240 boolean_t
241 db_symbol_is_ambiguous(sym)
242 	db_sym_t	sym;
243 {
244 	char		*sym_name;
245 	register int	i;
246 	register
247 	boolean_t	found_once = FALSE;
248 
249 	if (!db_qualify_ambiguous_names)
250 		return FALSE;
251 
252 	db_symbol_values(sym, &sym_name, 0);
253 	for (i = 0; i < db_nsymtab; i++) {
254 		if (X_db_lookup(&db_symtabs[i], sym_name)) {
255 			if (found_once)
256 				return TRUE;
257 			found_once = TRUE;
258 		}
259 	}
260 	return FALSE;
261 }
262 
263 /*
264  * Find the closest symbol to val, and return its name
265  * and the difference between val and the symbol found.
266  */
267 db_sym_t
268 db_search_symbol( val, strategy, offp)
269 	register db_addr_t	val;
270 	db_strategy_t		strategy;
271 	db_expr_t		*offp;
272 {
273 	register
274 	unsigned int	diff;
275 	unsigned int	newdiff;
276 	register int	i;
277 	db_sym_t	ret = DB_SYM_NULL, sym;
278 
279 	newdiff = diff = ~0;
280 	db_last_symtab = 0;
281 	for (i = 0; i < db_nsymtab; i++) {
282 	    sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff);
283 	    if (newdiff < diff) {
284 		db_last_symtab = &db_symtabs[i];
285 		diff = newdiff;
286 		ret = sym;
287 	    }
288 	}
289 	*offp = diff;
290 	return ret;
291 }
292 
293 /*
294  * Return name and value of a symbol
295  */
296 void
297 db_symbol_values(sym, namep, valuep)
298 	db_sym_t	sym;
299 	char		**namep;
300 	db_expr_t	*valuep;
301 {
302 	db_expr_t	value;
303 
304 	if (sym == DB_SYM_NULL) {
305 		*namep = 0;
306 		return;
307 	}
308 
309 	X_db_symbol_values(sym, namep, &value);
310 
311 	if (db_symbol_is_ambiguous(sym))
312 		*namep = db_qualify(sym, db_last_symtab->name);
313 	if (valuep)
314 		*valuep = value;
315 }
316 
317 
318 /*
319  * Print a the closest symbol to value
320  *
321  * After matching the symbol according to the given strategy
322  * we print it in the name+offset format, provided the symbol's
323  * value is close enough (eg smaller than db_maxoff).
324  * We also attempt to print [filename:linenum] when applicable
325  * (eg for procedure names).
326  *
327  * If we could not find a reasonable name+offset representation,
328  * then we just print the value in hex.  Small values might get
329  * bogus symbol associations, e.g. 3 might get some absolute
330  * value like _INCLUDE_VERSION or something, therefore we do
331  * not accept symbols whose value is zero (and use plain hex).
332  */
333 
334 unsigned int	db_maxoff = 0x10000000;
335 
336 void
337 db_printsym(off, strategy)
338 	db_expr_t	off;
339 	db_strategy_t	strategy;
340 {
341 	db_expr_t	d;
342 	char 		*filename;
343 	char		*name;
344 	db_expr_t	value;
345 	int 		linenum;
346 	db_sym_t	cursym;
347 
348 	cursym = db_search_symbol(off, strategy, &d);
349 	db_symbol_values(cursym, &name, &value);
350 	if (name == 0 || d >= db_maxoff || value == 0) {
351 		db_printf("%#n", off);
352 		return;
353 	}
354 	db_printf("%s", name);
355 	if (d)
356 		db_printf("+%#r", d);
357 	if (strategy == DB_STGY_PROC) {
358 		if (db_line_at_pc(cursym, &filename, &linenum, off))
359 			db_printf(" [%s:%d]", filename, linenum);
360 	}
361 }
362 
363 
364 boolean_t
365 db_line_at_pc( sym, filename, linenum, pc)
366 {
367 	return X_db_line_at_pc( db_last_symtab, sym, filename, linenum, pc);
368 }
369