xref: /netbsd-src/sys/ddb/db_sym.c (revision cda4f8f6ee55684e8d311b86c99ea59191e6b74f)
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  * db_sym.c,v 1.2 1993/05/20 03:39:31 cgd Exp
28  *
29  * HISTORY
30  * 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 #ifndef MAXLKMS
100 #define MAXLKMS 20
101 #endif
102 
103 #ifndef MAXNOSYMTABS
104 #define	MAXNOSYMTABS	MAXLKMS+1	/* Room for kernel + LKM's */
105 #endif
106 
107 db_symtab_t	db_symtabs[MAXNOSYMTABS] = {{0,},};
108 
109 db_symtab_t	*db_last_symtab;
110 
111 db_sym_t	db_lookup();	/* forward */
112 
113 /*
114  * Add symbol table, with given name, to list of symbol tables.
115  */
116 int
117 db_add_symbol_table(start, end, name, ref)
118 	char *start;
119 	char *end;
120 	char *name;
121 	char *ref;
122 {
123 	int slot;
124 
125 	for (slot = 0; slot < MAXNOSYMTABS; slot++) {
126 		if (db_symtabs[slot].name == NULL)
127 			break;
128 	}
129 	if (slot >= MAXNOSYMTABS) {
130 		printf ("No slots left for %s symbol table", name);
131 		return(-1);
132 	}
133 
134 	db_symtabs[slot].start = start;
135 	db_symtabs[slot].end = end;
136 	db_symtabs[slot].name = name;
137 	db_symtabs[slot].private = ref;
138 
139 	return(slot);
140 }
141 
142 /*
143  * Delete a symbol table. Caller is responsible for freeing storage.
144  */
145 void
146 db_del_symbol_table(name)
147 	char *name;
148 {
149 	int slot;
150 
151 	for (slot = 0; slot < MAXNOSYMTABS; slot++) {
152 		if (db_symtabs[slot].name &&
153 		    ! strcmp(db_symtabs[slot].name, name))
154 			break;
155 	}
156 	if (slot >= MAXNOSYMTABS) {
157 		printf ("Unable to find symbol table slot for %s.", name);
158 		return;
159 	}
160 
161 	db_symtabs[slot].start = 0;
162 	db_symtabs[slot].end = 0;
163 	db_symtabs[slot].name = 0;
164 	db_symtabs[slot].private = 0;
165 }
166 
167 /*
168  *  db_qualify("vm_map", "netbsd") returns "netbsd:vm_map".
169  *
170  *  Note: return value points to static data whose content is
171  *  overwritten by each call... but in practice this seems okay.
172  */
173 static char *
174 db_qualify(sym, symtabname)
175 	db_sym_t	sym;
176 	register char	*symtabname;
177 {
178 	char		*symname;
179 	static char     tmp[256];
180 	register char	*s;
181 
182 	db_symbol_values(sym, &symname, 0);
183 	s = tmp;
184 	while (*s++ = *symtabname++) {
185 	}
186 	s[-1] = ':';
187 	while (*s++ = *symname++) {
188 	}
189 	return tmp;
190 }
191 
192 
193 boolean_t
194 db_eqname(src, dst, c)
195 	char *src;
196 	char *dst;
197 	char c;
198 {
199 	if (!strcmp(src, dst))
200 	    return (TRUE);
201 	if (src[0] == c)
202 	    return (!strcmp(src+1,dst));
203 	return (FALSE);
204 }
205 
206 boolean_t
207 db_value_of_name(name, valuep)
208 	char		*name;
209 	db_expr_t	*valuep;
210 {
211 	db_sym_t	sym;
212 
213 	sym = db_lookup(name);
214 	if (sym == DB_SYM_NULL)
215 	    return (FALSE);
216 	db_symbol_values(sym, &name, valuep);
217 	return (TRUE);
218 }
219 
220 
221 /*
222  * Lookup a symbol.
223  * If the symbol has a qualifier (e.g., ux:vm_map),
224  * then only the specified symbol table will be searched;
225  * otherwise, all symbol tables will be searched.
226  */
227 db_sym_t
228 db_lookup(symstr)
229 	char *symstr;
230 {
231 	db_sym_t sp;
232 	register int i;
233 	int symtab_start = 0;
234 	int symtab_end = MAXNOSYMTABS;
235 	register char *cp;
236 
237 	/*
238 	 * Look for, remove, and remember any symbol table specifier.
239 	 */
240 	for (cp = symstr; *cp; cp++) {
241 		if (*cp == ':') {
242 			*cp = '\0';
243 			for (i = 0; i < MAXNOSYMTABS; i++) {
244 				if (db_symtabs[i].name &&
245 				    ! strcmp(symstr, db_symtabs[i].name)) {
246 					symtab_start = i;
247 					symtab_end = i + 1;
248 					break;
249 				}
250 			}
251 			*cp = ':';
252 			if (i == MAXNOSYMTABS) {
253 				db_error("invalid symbol table name");
254 			}
255 			symstr = cp+1;
256 		}
257 	}
258 
259 	/*
260 	 * Look in the specified set of symbol tables.
261 	 * Return on first match.
262 	 */
263 	for (i = symtab_start; i < symtab_end; i++) {
264 		if (db_symtabs[i].name &&
265 		    (sp = X_db_lookup(&db_symtabs[i], symstr))) {
266 			db_last_symtab = &db_symtabs[i];
267 			return sp;
268 		}
269 	}
270 	return 0;
271 }
272 
273 /*
274  * Does this symbol name appear in more than one symbol table?
275  * Used by db_symbol_values to decide whether to qualify a symbol.
276  */
277 boolean_t db_qualify_ambiguous_names = FALSE;
278 
279 boolean_t
280 db_symbol_is_ambiguous(sym)
281 	db_sym_t	sym;
282 {
283 	char		*sym_name;
284 	register int	i;
285 	register
286 	boolean_t	found_once = FALSE;
287 
288 	if (!db_qualify_ambiguous_names)
289 		return FALSE;
290 
291 	db_symbol_values(sym, &sym_name, 0);
292 	for (i = 0; i < MAXNOSYMTABS; i++) {
293 		if (db_symtabs[i].name &&
294 		    X_db_lookup(&db_symtabs[i], sym_name)) {
295 			if (found_once)
296 				return TRUE;
297 			found_once = TRUE;
298 		}
299 	}
300 	return FALSE;
301 }
302 
303 /*
304  * Find the closest symbol to val, and return its name
305  * and the difference between val and the symbol found.
306  */
307 db_sym_t
308 db_search_symbol( val, strategy, offp)
309 	register db_addr_t	val;
310 	db_strategy_t		strategy;
311 	db_expr_t		*offp;
312 {
313 	register
314 	unsigned int	diff;
315 	unsigned int	newdiff;
316 	register int	i;
317 	db_sym_t	ret = DB_SYM_NULL, sym;
318 
319 	newdiff = diff = ~0;
320 	db_last_symtab = 0;
321 	for (i = 0; i < MAXNOSYMTABS; i++) {
322 	    if (!db_symtabs[i].name)
323 	        continue;
324 	    sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff);
325 	    if (newdiff < diff) {
326 		db_last_symtab = &db_symtabs[i];
327 		diff = newdiff;
328 		ret = sym;
329 	    }
330 	}
331 	*offp = diff;
332 	return ret;
333 }
334 
335 /*
336  * Return name and value of a symbol
337  */
338 void
339 db_symbol_values(sym, namep, valuep)
340 	db_sym_t	sym;
341 	char		**namep;
342 	db_expr_t	*valuep;
343 {
344 	db_expr_t	value;
345 
346 	if (sym == DB_SYM_NULL) {
347 		*namep = 0;
348 		return;
349 	}
350 
351 	X_db_symbol_values(sym, namep, &value);
352 
353 	if (db_symbol_is_ambiguous(sym))
354 		*namep = db_qualify(sym, db_last_symtab->name);
355 	if (valuep)
356 		*valuep = value;
357 }
358 
359 
360 /*
361  * Print a the closest symbol to value
362  *
363  * After matching the symbol according to the given strategy
364  * we print it in the name+offset format, provided the symbol's
365  * value is close enough (eg smaller than db_maxoff).
366  * We also attempt to print [filename:linenum] when applicable
367  * (eg for procedure names).
368  *
369  * If we could not find a reasonable name+offset representation,
370  * then we just print the value in hex.  Small values might get
371  * bogus symbol associations, e.g. 3 might get some absolute
372  * value like _INCLUDE_VERSION or something, therefore we do
373  * not accept symbols whose value is zero (and use plain hex).
374  */
375 
376 unsigned int	db_maxoff = 0x10000000;
377 
378 void
379 db_printsym(off, strategy)
380 	db_expr_t	off;
381 	db_strategy_t	strategy;
382 {
383 	db_expr_t	d;
384 	char 		*filename;
385 	char		*name;
386 	db_expr_t	value;
387 	int 		linenum;
388 	db_sym_t	cursym;
389 
390 	cursym = db_search_symbol(off, strategy, &d);
391 	db_symbol_values(cursym, &name, &value);
392 	if (name == 0 || d >= db_maxoff || value == 0) {
393 		db_printf("%#n", off);
394 		return;
395 	}
396 	db_printf("%s", name);
397 	if (d)
398 		db_printf("+%#r", d);
399 	if (strategy == DB_STGY_PROC) {
400 		if (db_line_at_pc(cursym, &filename, &linenum, off))
401 			db_printf(" [%s:%d]", filename, linenum);
402 	}
403 }
404 
405 
406 boolean_t
407 db_line_at_pc( sym, filename, linenum, pc)
408 	db_sym_t	sym;
409 	char		**filename;
410 	int		*linenum;
411 	db_expr_t	pc;
412 {
413 	return X_db_line_at_pc( db_last_symtab, sym, filename, linenum, pc);
414 }
415 
416 int
417 db_sym_numargs(sym, nargp, argnames)
418 	db_sym_t	sym;
419 	int		*nargp;
420 	char		**argnames;
421 {
422 	return X_db_sym_numargs(db_last_symtab, sym, nargp, argnames);
423 }
424