1 /* $NetBSD: db_sym.c,v 1.58 2008/11/30 18:21:36 martin 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 1.58 2008/11/30 18:21:36 martin 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 47 static void db_symsplit(char *, char **, char **); 48 49 50 #ifdef DB_AOUT_SYMBOLS 51 #define TBLNAME "netbsd" 52 53 static int using_aout_symtab; 54 const db_symformat_t *db_symformat; 55 static db_forall_func_t db_sift; 56 extern 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 */ 65 void 66 ddb_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_addsyms_elf(symsize, vss, vse); /* Will complain if necessary */ 76 } 77 78 bool 79 db_eqname(const char *src, const 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 89 bool 90 db_value_of_name(const char *name, db_expr_t *valuep) 91 { 92 char symbol[128]; 93 char *mod, *sym; 94 unsigned long uval; 95 long val; 96 97 #ifdef DB_AOUT_SYMBOLS 98 db_sym_t ssym; 99 100 if (using_aout_symtab) { 101 /* 102 * Cannot load symtabs in a.out kernels, so the ':' 103 * style of selecting modules is irrelevant. 104 */ 105 ssym = (*db_symformat->sym_lookup)(NULL, name); 106 if (ssym == DB_SYM_NULL) 107 return (false); 108 db_symbol_values(ssym, &name, valuep); 109 return (true); 110 } 111 #endif 112 (void)strlcpy(symbol, name, sizeof(symbol)); 113 db_symsplit(symbol, &mod, &sym); 114 if (ksyms_getval_unlocked(mod, sym, &uval, KSYMS_EXTERN) == 0) { 115 val = (long) uval; 116 *valuep = (db_expr_t)val; 117 return true; 118 } 119 if (ksyms_getval_unlocked(mod, sym, &uval, KSYMS_ANY) == 0) { 120 val = (long) uval; 121 *valuep = (db_expr_t)val; 122 return true; 123 } 124 return false; 125 } 126 127 #ifdef DB_AOUT_SYMBOLS 128 /* Private structure for passing args to db_sift() from db_sifting(). */ 129 struct db_sift_args { 130 char *symstr; 131 int mode; 132 }; 133 134 /* 135 * Does the work of db_sifting(), called once for each 136 * symbol via db_forall(), prints out symbols matching 137 * criteria. 138 */ 139 static void 140 db_sift(db_symtab_t *stab, db_sym_t sym, char *name, 141 char *suffix, int prefix, void *arg) 142 { 143 char c, sc; 144 char *find, *p; 145 size_t len; 146 struct db_sift_args *dsa; 147 148 dsa = (struct db_sift_args*)arg; 149 150 find = dsa->symstr; /* String we're looking for. */ 151 p = name; /* String we're searching within. */ 152 153 /* Matching algorithm cribbed from strstr(), which is not 154 in the kernel. */ 155 if ((c = *find++) != 0) { 156 len = strlen(find); 157 do { 158 do { 159 if ((sc = *p++) == 0) 160 return; 161 } while (sc != c); 162 } while (strncmp(p, find, len) != 0); 163 } 164 if (dsa->mode=='F') /* ala ls -F */ 165 db_printf("%s%s ", name, suffix); 166 else 167 db_printf("%s ", name); 168 } 169 #endif 170 171 /* 172 * "Sift" for a partial symbol. 173 * Named for the Sun OpenPROM command ("sifting"). 174 * If the symbol has a qualifier (e.g., ux:vm_map), 175 * then only the specified symbol table will be searched; 176 * otherwise, all symbol tables will be searched.. 177 * 178 * "mode" is how-to-display, set from modifiers. 179 */ 180 void 181 db_sifting(char *symstr, int mode) 182 { 183 char *mod, *sym; 184 185 #ifdef DB_AOUT_SYMBOLS 186 struct db_sift_args dsa; 187 188 if (using_aout_symtab) { 189 dsa.symstr = symstr; 190 dsa.mode = mode; 191 (*db_symformat->sym_forall)(NULL, db_sift, &dsa); 192 db_printf("\n"); 193 return; 194 } 195 #endif 196 197 db_symsplit(symstr, &mod, &sym); 198 if (ksyms_sift(mod, sym, mode) == ENODEV) 199 db_error("invalid symbol table name"); 200 } 201 202 /* 203 * Find the closest symbol to val, and return its name 204 * and the difference between val and the symbol found. 205 */ 206 db_sym_t 207 db_search_symbol(db_addr_t val, db_strategy_t strategy, db_expr_t *offp) 208 { 209 unsigned int diff; 210 unsigned long naddr; 211 db_sym_t ret = DB_SYM_NULL; 212 const char *mod; 213 const char *sym; 214 215 #ifdef DB_AOUT_SYMBOLS 216 db_expr_t newdiff; 217 db_sym_t ssym; 218 219 if (using_aout_symtab) { 220 newdiff = diff = ~0; 221 ssym = (*db_symformat->sym_search) 222 (NULL, val, strategy, &newdiff); 223 if ((unsigned int) newdiff < diff) { 224 diff = newdiff; 225 ret = ssym; 226 } 227 *offp = diff; 228 return ret; 229 } 230 #endif 231 232 if (ksyms_getname(&mod, &sym, (vaddr_t)val, strategy) == 0) { 233 (void)ksyms_getval_unlocked(mod, sym, &naddr, KSYMS_ANY); 234 diff = val - (db_addr_t)naddr; 235 ret = (db_sym_t)naddr; 236 } else 237 diff = 0; 238 *offp = diff; 239 return ret; 240 } 241 242 /* 243 * Return name and value of a symbol 244 */ 245 void 246 db_symbol_values(db_sym_t sym, const char **namep, db_expr_t *valuep) 247 { 248 const char *mod; 249 250 if (sym == DB_SYM_NULL) { 251 *namep = 0; 252 return; 253 } 254 255 #ifdef DB_AOUT_SYMBOLS 256 if (using_aout_symtab) { 257 db_expr_t value; 258 (*db_symformat->sym_value)(NULL, sym, namep, &value); 259 if (valuep) 260 *valuep = value; 261 return; 262 } 263 #endif 264 265 if (ksyms_getname(&mod, namep, (vaddr_t)sym, 266 KSYMS_ANY|KSYMS_EXACT) == 0) { 267 if (valuep) 268 *valuep = sym; 269 } else 270 *namep = NULL; 271 } 272 273 274 /* 275 * Print a the closest symbol to value 276 * 277 * After matching the symbol according to the given strategy 278 * we print it in the name+offset format, provided the symbol's 279 * value is close enough (eg smaller than db_maxoff). 280 * We also attempt to print [filename:linenum] when applicable 281 * (eg for procedure names). 282 * 283 * If we could not find a reasonable name+offset representation, 284 * then we just print the value in hex. Small values might get 285 * bogus symbol associations, e.g. 3 might get some absolute 286 * value like _INCLUDE_VERSION or something, therefore we do 287 * not accept symbols whose value is zero (and use plain hex). 288 * Also, avoid printing as "end+0x????" which is useless. 289 * The variable db_lastsym is used instead of "end" in case we 290 * add support for symbols in loadable driver modules. 291 */ 292 extern char end[]; 293 unsigned long db_lastsym = (unsigned long)end; 294 unsigned int db_maxoff = 0x100000; 295 296 void 297 db_symstr(char *buf, size_t buflen, db_expr_t off, db_strategy_t strategy) 298 { 299 const char *name; 300 const char *mod; 301 unsigned long val; 302 303 #ifdef DB_AOUT_SYMBOLS 304 if (using_aout_symtab) { 305 db_expr_t d; 306 char *filename; 307 db_expr_t value; 308 int linenum; 309 db_sym_t cursym; 310 311 if ((unsigned long) off <= db_lastsym) { 312 cursym = db_search_symbol(off, strategy, &d); 313 db_symbol_values(cursym, &name, &value); 314 if (name != NULL && 315 ((unsigned int) d < db_maxoff) && 316 value != 0) { 317 strlcpy(buf, name, buflen); 318 if (d) { 319 strlcat(buf, "+", buflen); 320 db_format_radix(buf+strlen(buf), 321 24, d, true); 322 } 323 if (strategy == DB_STGY_PROC) { 324 if ((*db_symformat->sym_line_at_pc) 325 (NULL, cursym, &filename, 326 &linenum, off)) 327 snprintf(buf + strlen(buf), 328 buflen - strlen(buf), 329 " [%s:%d]", 330 filename, linenum); 331 } 332 return; 333 } 334 } 335 strlcpy(buf, db_num_to_str(off), buflen); 336 return; 337 } 338 #endif 339 if (ksyms_getname(&mod, &name, (vaddr_t)off, 340 strategy|KSYMS_CLOSEST) == 0) { 341 (void)ksyms_getval_unlocked(mod, name, &val, KSYMS_ANY); 342 if (((off - val) < db_maxoff) && val) { 343 snprintf(buf, buflen, "%s:%s", mod, name); 344 if (off - val) { 345 strlcat(buf, "+", buflen); 346 db_format_radix(buf+strlen(buf), 347 24, off - val, true); 348 } 349 #ifdef notyet 350 if (strategy & KSYMS_PROC) { 351 if (ksyms_fmaddr(off, &filename, &linenum) == 0) 352 snprintf(buf + strlen(buf), 353 buflen - strlen(buf), 354 " [%s:%d]", filename, linenum); 355 } 356 #endif 357 return; 358 } 359 } 360 strlcpy(buf, db_num_to_str(off), buflen); 361 } 362 363 void 364 db_printsym(db_expr_t off, db_strategy_t strategy, 365 void (*pr)(const char *, ...)) 366 { 367 const char *name; 368 const char *mod; 369 unsigned long uval; 370 long val; 371 #ifdef notyet 372 char *filename; 373 int linenum; 374 #endif 375 376 #ifdef DB_AOUT_SYMBOLS 377 if (using_aout_symtab) { 378 db_expr_t d; 379 char *filename; 380 db_expr_t value; 381 int linenum; 382 db_sym_t cursym; 383 if ((unsigned long) off <= db_lastsym) { 384 cursym = db_search_symbol(off, strategy, &d); 385 db_symbol_values(cursym, &name, &value); 386 if (name != NULL && 387 ((unsigned int) d < db_maxoff) && 388 value != 0) { 389 (*pr)("%s", name); 390 if (d) { 391 char tbuf[24]; 392 393 db_format_radix(tbuf, 24, d, true); 394 (*pr)("+%s", tbuf); 395 } 396 if (strategy == DB_STGY_PROC) { 397 if ((*db_symformat->sym_line_at_pc) 398 (NULL, cursym, &filename, 399 &linenum, off)) 400 (*pr)(" [%s:%d]", 401 filename, linenum); 402 } 403 return; 404 } 405 } 406 (*pr)(db_num_to_str(off)); 407 return; 408 } 409 #endif 410 if (ksyms_getname(&mod, &name, (vaddr_t)off, 411 strategy|KSYMS_CLOSEST) == 0) { 412 (void)ksyms_getval_unlocked(mod, name, &uval, KSYMS_ANY); 413 val = (long) uval; 414 if (((off - val) < db_maxoff) && val) { 415 (*pr)("%s:%s", mod, name); 416 if (off - val) { 417 char tbuf[24]; 418 419 db_format_radix(tbuf, 24, off - val, true); 420 (*pr)("+%s", tbuf); 421 } 422 #ifdef notyet 423 if (strategy & KSYMS_PROC) { 424 if (ksyms_fmaddr(off, &filename, &linenum) == 0) 425 (*pr)(" [%s:%d]", filename, linenum); 426 } 427 #endif 428 return; 429 } 430 } 431 (*pr)(db_num_to_str(off)); 432 return; 433 } 434 435 /* 436 * Splits a string in the form "mod:sym" to two strings. 437 */ 438 static void 439 db_symsplit(char *str, char **mod, char **sym) 440 { 441 char *cp; 442 443 if ((cp = strchr(str, ':')) != NULL) { 444 *cp++ = '\0'; 445 *mod = str; 446 *sym = cp; 447 } else { 448 *mod = NULL; 449 *sym = str; 450 } 451 } 452 453 bool 454 db_sym_numargs(db_sym_t cursym, int *nargp, char **argnamep) 455 { 456 #ifdef DB_AOUT_SYMBOLS 457 if (using_aout_symtab) 458 return ((*db_symformat->sym_numargs)(NULL, cursym, nargp, 459 argnamep)); 460 #endif 461 return (false); 462 } 463 464