db_sym.c revision 1.42 
1/*	$NetBSD: db_sym.c,v 1.42 2003/09/03 10:45:10 ragge Exp $	*/
2
3/*
4 * Mach Operating System
5 * Copyright (c) 1991,1990 Carnegie Mellon University
6 * All Rights Reserved.
7 *
8 * Permission to use, copy, modify and distribute this software and its
9 * documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21 *  School of Computer Science
22 *  Carnegie Mellon University
23 *  Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
27 */
28
29#include <sys/cdefs.h>
30__KERNEL_RCSID(0, "$NetBSD: db_sym.c,v 1.42 2003/09/03 10:45:10 ragge Exp $");
31
32#include "opt_ddbparam.h"
33
34#include <sys/param.h>
35#include <sys/proc.h>
36#include <sys/systm.h>
37#include <sys/ksyms.h>
38
39#include <machine/db_machdep.h>
40
41#include <ddb/db_lex.h>
42#include <ddb/db_sym.h>
43#include <ddb/db_output.h>
44#include <ddb/db_extern.h>
45#include <ddb/db_command.h>
46
47static void		db_symsplit(char *, char **, char **);
48
49
50#ifdef DB_AOUT_SYMBOLS
51#define	TBLNAME	"netbsd"
52
53static int using_aout_symtab;
54const db_symformat_t *db_symformat;
55static db_forall_func_t db_sift;
56extern db_symformat_t db_symformat_aout;
57#endif
58
59
60/*
61 * Initialize the kernel debugger by initializing the master symbol
62 * table.  Note that if initializing the master symbol table fails,
63 * no other symbol tables can be loaded.
64 */
65void
66ddb_init(int symsize, void *vss, void *vse)
67{
68#ifdef DB_AOUT_SYMBOLS
69	db_symformat = &db_symformat_aout;
70	if ((*db_symformat->sym_init)(symsize, vss, vse, TBLNAME) == TRUE) {
71		using_aout_symtab = TRUE;
72		return;
73	}
74#endif
75	ksyms_init(symsize, vss, vse);	/* Will complain if necessary */
76}
77
78boolean_t
79db_eqname(char *src, char *dst, int c)
80{
81
82	if (!strcmp(src, dst))
83		return (TRUE);
84	if (src[0] == c)
85		return (!strcmp(src+1,dst));
86	return (FALSE);
87}
88
89boolean_t
90db_value_of_name(char *name, db_expr_t *valuep)
91{
92	char *mod, *sym;
93	unsigned long val;
94
95#ifdef DB_AOUT_SYMBOLS
96	db_sym_t	ssym;
97
98	if (using_aout_symtab) {
99		/*
100		 * Cannot load symtabs in a.out kernels, so the ':'
101		 * style of selecting modules is irrelevant.
102		 */
103		ssym = (*db_symformat->sym_lookup)(NULL, name);
104		if (ssym == DB_SYM_NULL)
105			return (FALSE);
106		db_symbol_values(ssym, &name, valuep);
107		return (TRUE);
108	}
109#endif
110	db_symsplit(name, &mod, &sym);
111	if (ksyms_getval(mod, sym, &val, KSYMS_EXTERN) == 0) {
112		*valuep = (db_expr_t)val;
113		return TRUE;
114	}
115	if (ksyms_getval(mod, sym, &val, KSYMS_ANY) == 0) {
116		*valuep = (db_expr_t)val;
117		return TRUE;
118	}
119	return FALSE;
120}
121
122#ifdef DB_AOUT_SYMBOLS
123/* Private structure for passing args to db_sift() from db_sifting(). */
124struct db_sift_args {
125	char	*symstr;
126	int	mode;
127};
128
129/*
130 * Does the work of db_sifting(), called once for each
131 * symbol via db_forall(), prints out symbols matching
132 * criteria.
133 */
134static void
135db_sift(db_symtab_t *stab, db_sym_t sym, char *name, char *suffix, int prefix,
136    void *arg)
137{
138	char c, sc;
139	char *find, *p;
140	size_t len;
141	struct db_sift_args *dsa;
142
143	dsa = (struct db_sift_args*)arg;
144
145	find = dsa->symstr;	/* String we're looking for. */
146	p = name;		/* String we're searching within. */
147
148	/* Matching algorithm cribbed from strstr(), which is not
149	   in the kernel. */
150	if ((c = *find++) != 0) {
151		len = strlen(find);
152		do {
153			do {
154				if ((sc = *p++) == 0)
155					return;
156			} while (sc != c);
157		} while (strncmp(p, find, len) != 0);
158	}
159	if (dsa->mode=='F')	/* ala ls -F */
160		db_printf("%s%s ", name, suffix);
161	else
162		db_printf("%s ", name);
163}
164#endif
165
166/*
167 * "Sift" for a partial symbol.
168 * Named for the Sun OpenPROM command ("sifting").
169 * If the symbol has a qualifier (e.g., ux:vm_map),
170 * then only the specified symbol table will be searched;
171 * otherwise, all symbol tables will be searched..
172 *
173 * "mode" is how-to-display, set from modifiers.
174 */
175void
176db_sifting(char *symstr, int mode)
177{
178	char *mod, *sym;
179
180#ifdef DB_AOUT_SYMBOLS
181	struct db_sift_args dsa;
182
183	if (using_aout_symtab) {
184		dsa.symstr = symstr;
185		dsa.mode = mode;
186		(*db_symformat->sym_forall)(NULL, db_sift, &dsa);
187		db_printf("\n");
188		return;
189	}
190#endif
191
192	db_symsplit(symstr, &mod, &sym);
193	if (ksyms_sift(mod, sym, mode) == ENODEV)
194		db_error("invalid symbol table name");
195}
196
197/*
198 * Find the closest symbol to val, and return its name
199 * and the difference between val and the symbol found.
200 */
201db_sym_t
202db_search_symbol(db_addr_t val, db_strategy_t strategy, db_expr_t *offp)
203{
204	unsigned int diff;
205	unsigned long naddr;
206	db_sym_t ret = DB_SYM_NULL;
207	const char *mod;
208	char *sym;
209
210#ifdef DB_AOUT_SYMBOLS
211	db_expr_t newdiff;
212	db_sym_t ssym;
213
214	if (using_aout_symtab) {
215		newdiff = diff = ~0;
216		ssym = (*db_symformat->sym_search)
217		    (NULL, val, strategy, &newdiff);
218		if ((unsigned int) newdiff < diff) {
219			diff = newdiff;
220			ret = ssym;
221		}
222		*offp = diff;
223		return ret;
224	}
225#endif
226
227	if (ksyms_getname(&mod, &sym, (vaddr_t)val, strategy) == 0) {
228		(void)ksyms_getval(mod, sym, &naddr, KSYMS_ANY);
229		diff = val - (db_addr_t)naddr;
230		ret = (db_sym_t)naddr;
231	}
232	*offp = diff;
233	return ret;
234}
235
236/*
237 * Return name and value of a symbol
238 */
239void
240db_symbol_values(db_sym_t sym, char **namep, db_expr_t *valuep)
241{
242	const char *mod;
243
244	if (sym == DB_SYM_NULL) {
245		*namep = 0;
246		return;
247	}
248
249#ifdef DB_AOUT_SYMBOLS
250	if (using_aout_symtab) {
251		db_expr_t value;
252		(*db_symformat->sym_value)(NULL, sym, namep, &value);
253		if (valuep)
254			*valuep = value;
255		return;
256	}
257#endif
258
259	if (ksyms_getname(&mod, namep, (vaddr_t)sym,
260	    KSYMS_ANY|KSYMS_EXACT) == 0) {
261		if (valuep)
262			*valuep = sym;
263	} else
264		*namep = NULL;
265}
266
267
268/*
269 * Print a the closest symbol to value
270 *
271 * After matching the symbol according to the given strategy
272 * we print it in the name+offset format, provided the symbol's
273 * value is close enough (eg smaller than db_maxoff).
274 * We also attempt to print [filename:linenum] when applicable
275 * (eg for procedure names).
276 *
277 * If we could not find a reasonable name+offset representation,
278 * then we just print the value in hex.  Small values might get
279 * bogus symbol associations, e.g. 3 might get some absolute
280 * value like _INCLUDE_VERSION or something, therefore we do
281 * not accept symbols whose value is zero (and use plain hex).
282 * Also, avoid printing as "end+0x????" which is useless.
283 * The variable db_lastsym is used instead of "end" in case we
284 * add support for symbols in loadable driver modules.
285 */
286extern char end[];
287unsigned long	db_lastsym = (unsigned long)end;
288unsigned int	db_maxoff = 0x10000000;
289
290void
291db_symstr(char *buf, size_t buflen, db_expr_t off, db_strategy_t strategy)
292{
293	char  *name;
294	const char *mod;
295	unsigned long val;
296
297#ifdef DB_AOUT_SYMBOLS
298	if (using_aout_symtab) {
299		db_expr_t	d;
300		char 		*filename;
301		char		*name;
302		db_expr_t	value;
303		int 		linenum;
304		db_sym_t	cursym;
305
306		if ((unsigned long) off <= db_lastsym) {
307			cursym = db_search_symbol(off, strategy, &d);
308			db_symbol_values(cursym, &name, &value);
309			if (name != NULL &&
310			    ((unsigned int) d < db_maxoff) &&
311			    value != 0) {
312				strlcpy(buf, name, buflen);
313				if (d) {
314					strlcat(buf, "+", buflen);
315					db_format_radix(buf+strlen(buf),
316					    24, d, TRUE);
317				}
318				if (strategy == DB_STGY_PROC) {
319					if ((*db_symformat->sym_line_at_pc)
320					    (NULL, cursym, &filename,
321					    &linenum, off))
322						sprintf(buf+strlen(buf),
323						    " [%s:%d]",
324						    filename, linenum);
325				}
326				return;
327			}
328		}
329		strlcpy(buf, db_num_to_str(off), buflen);
330		return;
331	}
332#endif
333	if (ksyms_getname(&mod, &name, (vaddr_t)off,
334	    strategy|KSYMS_CLOSEST) == 0) {
335		(void)ksyms_getval(mod, name, &val, KSYMS_ANY);
336		if (((off - val) < db_maxoff) && val) {
337			sprintf(buf, "%s:%s", mod, name);
338			if (off - val) {
339				strlcat(buf, "+", buflen);
340				db_format_radix(buf+strlen(buf),
341				    24, off - val, TRUE);
342			}
343#ifdef notyet
344			if (strategy & KSYMS_PROC) {
345				if (ksyms_fmaddr(off, &filename, &linenum) == 0)					sprintf(buf+strlen(buf),
346					    " [%s:%d]", filename, linenum);
347			}
348#endif
349			return;
350		}
351	}
352	strlcpy(buf, db_num_to_str(off), buflen);
353}
354
355void
356db_printsym(db_expr_t off, db_strategy_t strategy,
357    void (*pr)(const char *, ...))
358{
359	char  *name;
360	const char *mod;
361	unsigned long val;
362#ifdef notyet
363	char *filename;
364	int  linenum;
365#endif
366
367#ifdef DB_AOUT_SYMBOLS
368	if (using_aout_symtab) {
369		db_expr_t	d;
370		char 		*filename;
371		char		*name;
372		db_expr_t	value;
373		int 		linenum;
374		db_sym_t	cursym;
375		if ((unsigned long) off <= db_lastsym) {
376			cursym = db_search_symbol(off, strategy, &d);
377			db_symbol_values(cursym, &name, &value);
378			if (name != NULL &&
379			    ((unsigned int) d < db_maxoff) &&
380			    value != 0) {
381				(*pr)("%s", name);
382				if (d) {
383					char tbuf[24];
384
385					db_format_radix(tbuf, 24, d, TRUE);
386					(*pr)("+%s", tbuf);
387				}
388				if (strategy == DB_STGY_PROC) {
389					if ((*db_symformat->sym_line_at_pc)
390					    (NULL, cursym, &filename,
391					    &linenum, off))
392						(*pr)(" [%s:%d]",
393						    filename, linenum);
394				}
395				return;
396			}
397		}
398		(*pr)(db_num_to_str(off));
399		return;
400	}
401#endif
402	if (ksyms_getname(&mod, &name, (vaddr_t)off,
403	    strategy|KSYMS_CLOSEST) == 0) {
404		(void)ksyms_getval(mod, name, &val, KSYMS_ANY);
405		if (((off - val) < db_maxoff) && val) {
406			(*pr)("%s:%s", mod, name);
407			if (off - val) {
408				char tbuf[24];
409
410				db_format_radix(tbuf, 24, off - val, TRUE);
411				(*pr)("+%s", tbuf);
412			}
413#ifdef notyet
414			if (strategy & KSYMS_PROC) {
415				if (ksyms_fmaddr(off, &filename, &linenum) == 0)
416					(*pr)(" [%s:%d]", filename, linenum);
417			}
418#endif
419			return;
420		}
421	}
422	(*pr)(db_num_to_str(off));
423	return;
424}
425
426/*
427 * Splits a string in the form "mod:sym" to two strings.
428 */
429static void
430db_symsplit(char *str, char **mod, char **sym)
431{
432	char *cp;
433
434	if ((cp = strchr(str, ':')) != NULL) {
435		*cp++ = '\0';
436		*mod = str;
437		*sym = cp;
438	} else {
439		*mod = NULL;
440		*sym = str;
441	}
442}
443
444boolean_t
445db_sym_numargs(db_sym_t cursym, int *nargp, char **argnamep)
446{
447#ifdef DB_AOUT_SYMBOLS
448	if (using_aout_symtab)
449		return ((*db_symformat->sym_numargs)(NULL, cursym, nargp,
450		    argnamep));
451#endif
452	return (FALSE);
453}
454
455