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#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: head/sys/ddb/db_sym.c 206639 2010-04-14 23:06:07Z julian $");
33
34#include <sys/param.h>
35#include <sys/pcpu.h>
36#include <sys/smp.h>
37#include <sys/systm.h>
38
39#include <net/vnet.h>
40
41#include <ddb/ddb.h>
42#include <ddb/db_sym.h>
43#include <ddb/db_variables.h>
44
45#include <opt_ddb.h>
46
47/*
48 * Multiple symbol tables
49 */
50#ifndef MAXNOSYMTABS
51#define MAXNOSYMTABS 3 /* mach, ux, emulator */
52#endif
53
54static db_symtab_t db_symtabs[MAXNOSYMTABS] = {{0,},};
55static int db_nsymtab = 0;
56
57static db_symtab_t *db_last_symtab; /* where last symbol was found */
58
59static c_db_sym_t db_lookup( const char *symstr);
60static char *db_qualify(c_db_sym_t sym, char *symtabname);
61static boolean_t db_symbol_is_ambiguous(c_db_sym_t sym);
62static boolean_t db_line_at_pc(c_db_sym_t, char **, int *, db_expr_t);
63
64static int db_cpu = -1;
65
66#ifdef VIMAGE
67static void *db_vnet = NULL;
68#endif
69
70/*
71 * Validate the CPU number used to interpret per-CPU variables so we can
72 * avoid later confusion if an invalid CPU is requested.
73 */
74int
75db_var_db_cpu(struct db_variable *vp, db_expr_t *valuep, int op)
76{
77
78 switch (op) {
79 case DB_VAR_GET:
80 *valuep = db_cpu;
81 return (1);
82
83 case DB_VAR_SET:
84 if (*(int *)valuep < -1 && *(int *)valuep > mp_maxid) {
85 db_printf("Invalid value: %d", *(int*)valuep);
86 return (0);
87 }
88 db_cpu = *(int *)valuep;
89 return (1);
90
91 default:
92 db_printf("db_var_db_cpu: unknown operation\n");
93 return (0);
94 }
95}
96
97/*
98 * Read-only variable reporting the current CPU, which is what we use when
99 * db_cpu is set to -1.
100 */
101int
102db_var_curcpu(struct db_variable *vp, db_expr_t *valuep, int op)
103{
104
105 switch (op) {
106 case DB_VAR_GET:
107 *valuep = curcpu;
108 return (1);
109
110 case DB_VAR_SET:
111 db_printf("Read-only variable.\n");
112 return (0);
113
114 default:
115 db_printf("db_var_curcpu: unknown operation\n");
116 return (0);
117 }
118}
119
120#ifdef VIMAGE
121/*
122 * Validate the virtual network pointer used to interpret per-vnet global
123 * variable expansion. Right now we don't do much here, really we should
124 * walk the global vnet list to check it's an OK pointer.
125 */
126int
127db_var_db_vnet(struct db_variable *vp, db_expr_t *valuep, int op)
128{
129
130 switch (op) {
131 case DB_VAR_GET:
132 *valuep = (db_expr_t)db_vnet;
133 return (1);
134
135 case DB_VAR_SET:
136 db_vnet = *(void **)valuep;
137 return (1);
138
139 default:
140 db_printf("db_var_db_vnet: unknown operation\n");
141 return (0);
142 }
143}
144
145/*
146 * Read-only variable reporting the current vnet, which is what we use when
147 * db_vnet is set to NULL.
148 */
149int
150db_var_curvnet(struct db_variable *vp, db_expr_t *valuep, int op)
151{
152
153 switch (op) {
154 case DB_VAR_GET:
155 *valuep = (db_expr_t)curvnet;
156 return (1);
157
158 case DB_VAR_SET:
159 db_printf("Read-only variable.\n");
160 return (0);
161
162 default:
163 db_printf("db_var_curcpu: unknown operation\n");
164 return (0);
165 }
166}
167#endif
168
169/*
170 * Add symbol table, with given name, to list of symbol tables.
171 */
172void
173db_add_symbol_table(start, end, name, ref)
174 char *start;
175 char *end;
176 char *name;
177 char *ref;
178{
179 if (db_nsymtab >= MAXNOSYMTABS) {
180 printf ("No slots left for %s symbol table", name);
181 panic ("db_sym.c: db_add_symbol_table");
182 }
183
184 db_symtabs[db_nsymtab].start = start;
185 db_symtabs[db_nsymtab].end = end;
186 db_symtabs[db_nsymtab].name = name;
187 db_symtabs[db_nsymtab].private = ref;
188 db_nsymtab++;
189}
190
191/*
192 * db_qualify("vm_map", "ux") returns "unix:vm_map".
193 *
194 * Note: return value points to static data whose content is
195 * overwritten by each call... but in practice this seems okay.
196 */
197static char *
198db_qualify(sym, symtabname)
199 c_db_sym_t sym;
200 register char *symtabname;
201{
202 const char *symname;
203 static char tmp[256];
204
205 db_symbol_values(sym, &symname, 0);
206 snprintf(tmp, sizeof(tmp), "%s:%s", symtabname, symname);
207 return tmp;
208}
209
210
211boolean_t
212db_eqname(src, dst, c)
213 const char *src;
214 const char *dst;
215 int c;
216{
217 if (!strcmp(src, dst))
218 return (TRUE);
219 if (src[0] == c)
220 return (!strcmp(src+1,dst));
221 return (FALSE);
222}
223
224boolean_t
225db_value_of_name(name, valuep)
226 const char *name;
227 db_expr_t *valuep;
228{
229 c_db_sym_t sym;
230
231 sym = db_lookup(name);
232 if (sym == C_DB_SYM_NULL)
233 return (FALSE);
234 db_symbol_values(sym, &name, valuep);
235 return (TRUE);
236}
237
238boolean_t
239db_value_of_name_pcpu(name, valuep)
240 const char *name;
241 db_expr_t *valuep;
242{
243 static char tmp[256];
244 db_expr_t value;
245 c_db_sym_t sym;
246 int cpu;
247
248 if (db_cpu != -1)
249 cpu = db_cpu;
250 else
251 cpu = curcpu;
252 snprintf(tmp, sizeof(tmp), "pcpu_entry_%s", name);
253 sym = db_lookup(tmp);
254 if (sym == C_DB_SYM_NULL)
255 return (FALSE);
256 db_symbol_values(sym, &name, &value);
257 if (value < DPCPU_START || value >= DPCPU_STOP)
258 return (FALSE);
259 *valuep = (db_expr_t)((uintptr_t)value + dpcpu_off[cpu]);
260 return (TRUE);
261}
262
263boolean_t
264db_value_of_name_vnet(name, valuep)
265 const char *name;
266 db_expr_t *valuep;
267{
268#ifdef VIMAGE
269 static char tmp[256];
270 db_expr_t value;
271 c_db_sym_t sym;
272 struct vnet *vnet;
273
274 if (db_vnet != NULL)
275 vnet = db_vnet;
276 else
277 vnet = curvnet;
278 snprintf(tmp, sizeof(tmp), "vnet_entry_%s", name);
279 sym = db_lookup(tmp);
280 if (sym == C_DB_SYM_NULL)
281 return (FALSE);
282 db_symbol_values(sym, &name, &value);
283 if (value < VNET_START || value >= VNET_STOP)
284 return (FALSE);
285 *valuep = (db_expr_t)((uintptr_t)value + vnet->vnet_data_base);
286 return (TRUE);
287#else
288 return (FALSE);
289#endif
290}
291
292/*
293 * Lookup a symbol.
294 * If the symbol has a qualifier (e.g., ux:vm_map),
295 * then only the specified symbol table will be searched;
296 * otherwise, all symbol tables will be searched.
297 */
298static c_db_sym_t
299db_lookup(symstr)
300 const char *symstr;
301{
302 c_db_sym_t sp;
303 register int i;
304 int symtab_start = 0;
305 int symtab_end = db_nsymtab;
306 register const char *cp;
307
308 /*
309 * Look for, remove, and remember any symbol table specifier.
310 */
311 for (cp = symstr; *cp; cp++) {
312 if (*cp == ':') {
313 for (i = 0; i < db_nsymtab; i++) {
314 int n = strlen(db_symtabs[i].name);
315
316 if (
317 n == (cp - symstr) &&
318 strncmp(symstr, db_symtabs[i].name, n) == 0
319 ) {
320 symtab_start = i;
321 symtab_end = i + 1;
322 break;
323 }
324 }
325 if (i == db_nsymtab) {
326 db_error("invalid symbol table name");
327 }
328 symstr = cp+1;
329 }
330 }
331
332 /*
333 * Look in the specified set of symbol tables.
334 * Return on first match.
335 */
336 for (i = symtab_start; i < symtab_end; i++) {
337 sp = X_db_lookup(&db_symtabs[i], symstr);
338 if (sp) {
339 db_last_symtab = &db_symtabs[i];
340 return sp;
341 }
342 }
343 return 0;
344}
345
346/*
347 * If TRUE, check across symbol tables for multiple occurrences
348 * of a name. Might slow things down quite a bit.
349 */
350static volatile boolean_t db_qualify_ambiguous_names = FALSE;
351
352/*
353 * Does this symbol name appear in more than one symbol table?
354 * Used by db_symbol_values to decide whether to qualify a symbol.
355 */
356static boolean_t
357db_symbol_is_ambiguous(sym)
358 c_db_sym_t sym;
359{
360 const char *sym_name;
361 register int i;
362 register
363 boolean_t found_once = FALSE;
364
365 if (!db_qualify_ambiguous_names)
366 return FALSE;
367
368 db_symbol_values(sym, &sym_name, 0);
369 for (i = 0; i < db_nsymtab; i++) {
370 if (X_db_lookup(&db_symtabs[i], sym_name)) {
371 if (found_once)
372 return TRUE;
373 found_once = TRUE;
374 }
375 }
376 return FALSE;
377}
378
379/*
380 * Find the closest symbol to val, and return its name
381 * and the difference between val and the symbol found.
382 */
383c_db_sym_t
384db_search_symbol( val, strategy, offp)
385 register db_addr_t val;
386 db_strategy_t strategy;
387 db_expr_t *offp;
388{
389 register
390 unsigned int diff;
391 size_t newdiff;
392 register int i;
393 c_db_sym_t ret = C_DB_SYM_NULL, sym;
394
395 newdiff = diff = ~0;
396 for (i = 0; i < db_nsymtab; i++) {
397 sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff);
398 if (newdiff < diff) {
399 db_last_symtab = &db_symtabs[i];
400 diff = newdiff;
401 ret = sym;
402 }
403 }
404 *offp = diff;
405 return ret;
406}
407
408/*
409 * Return name and value of a symbol
410 */
411void
412db_symbol_values(sym, namep, valuep)
413 c_db_sym_t sym;
414 const char **namep;
415 db_expr_t *valuep;
416{
417 db_expr_t value;
418
419 if (sym == DB_SYM_NULL) {
420 *namep = 0;
421 return;
422 }
423
424 X_db_symbol_values(db_last_symtab, sym, namep, &value);
425
426 if (db_symbol_is_ambiguous(sym))
427 *namep = db_qualify(sym, db_last_symtab->name);
428 if (valuep)
429 *valuep = value;
430}
431
432
433/*
434 * Print a the closest symbol to value
435 *
436 * After matching the symbol according to the given strategy
437 * we print it in the name+offset format, provided the symbol's
438 * value is close enough (eg smaller than db_maxoff).
439 * We also attempt to print [filename:linenum] when applicable
440 * (eg for procedure names).
441 *
442 * If we could not find a reasonable name+offset representation,
443 * then we just print the value in hex. Small values might get
444 * bogus symbol associations, e.g. 3 might get some absolute
445 * value like _INCLUDE_VERSION or something, therefore we do
446 * not accept symbols whose value is "small" (and use plain hex).
447 */
448
449db_expr_t db_maxoff = 0x10000;
450
451void
452db_printsym(off, strategy)
453 db_expr_t off;
454 db_strategy_t strategy;
455{
456 db_expr_t d;
457 char *filename;
458 const char *name;
459 db_expr_t value;
460 int linenum;
461 c_db_sym_t cursym;
462
463 cursym = db_search_symbol(off, strategy, &d);
464 db_symbol_values(cursym, &name, &value);
465 if (name == 0)
466 value = off;
467 if (value >= DB_SMALL_VALUE_MIN && value <= DB_SMALL_VALUE_MAX) {
468 db_printf("%+#lr", (long)off);
469 return;
470 }
471 if (name == 0 || d >= (unsigned long)db_maxoff) {
472 db_printf("%#lr", (unsigned long)off);
473 return;
474 }
475#ifdef DDB_NUMSYM
476 db_printf("%#lr = %s", (unsigned long)off, name);
477#else
478 db_printf("%s", name);
479#endif
480 if (d)
481 db_printf("+%+#lr", (long)d);
482 if (strategy == DB_STGY_PROC) {
483 if (db_line_at_pc(cursym, &filename, &linenum, off))
484 db_printf(" [%s:%d]", filename, linenum);
485 }
486}
487
488static boolean_t
489db_line_at_pc( sym, filename, linenum, pc)
490 c_db_sym_t sym;
491 char **filename;
492 int *linenum;
493 db_expr_t pc;
494{
495 return X_db_line_at_pc( db_last_symtab, sym, filename, linenum, pc);
496}
497
498int
499db_sym_numargs(sym, nargp, argnames)
500 c_db_sym_t sym;
501 int *nargp;
502 char **argnames;
503{
504 return X_db_sym_numargs(db_last_symtab, sym, nargp, argnames);
505}