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("$FreeBSD$"); 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 54 static db_symtab_t db_symtabs[MAXNOSYMTABS] = {{0,},}; 55 static int db_nsymtab = 0; 56 57 static db_symtab_t *db_last_symtab; /* where last symbol was found */ 58 59 static c_db_sym_t db_lookup( const char *symstr); 60 static char *db_qualify(c_db_sym_t sym, char *symtabname); 61 static bool db_symbol_is_ambiguous(c_db_sym_t sym); 62 static bool db_line_at_pc(c_db_sym_t, char **, int *, db_expr_t); 63 64 static int db_cpu = -1; 65 66 #ifdef VIMAGE 67 static 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 */ 74 int 75 db_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 */ 101 int 102 db_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 */ 126 int 127 db_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 */ 149 int 150 db_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_curvnet: 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 */ 172 void 173 db_add_symbol_table(char *start, char *end, char *name, char *ref) 174 { 175 if (db_nsymtab >= MAXNOSYMTABS) { 176 printf ("No slots left for %s symbol table", name); 177 panic ("db_sym.c: db_add_symbol_table"); 178 } 179 180 db_symtabs[db_nsymtab].start = start; 181 db_symtabs[db_nsymtab].end = end; 182 db_symtabs[db_nsymtab].name = name; 183 db_symtabs[db_nsymtab].private = ref; 184 db_nsymtab++; 185 } 186 187 /* 188 * db_qualify("vm_map", "ux") returns "unix:vm_map". 189 * 190 * Note: return value points to static data whose content is 191 * overwritten by each call... but in practice this seems okay. 192 */ 193 static char * 194 db_qualify(c_db_sym_t sym, char *symtabname) 195 { 196 const char *symname; 197 static char tmp[256]; 198 199 db_symbol_values(sym, &symname, 0); 200 snprintf(tmp, sizeof(tmp), "%s:%s", symtabname, symname); 201 return tmp; 202 } 203 204 205 bool 206 db_eqname(const char *src, const char *dst, int c) 207 { 208 if (!strcmp(src, dst)) 209 return (true); 210 if (src[0] == c) 211 return (!strcmp(src+1,dst)); 212 return (false); 213 } 214 215 bool 216 db_value_of_name(const char *name, db_expr_t *valuep) 217 { 218 c_db_sym_t sym; 219 220 sym = db_lookup(name); 221 if (sym == C_DB_SYM_NULL) 222 return (false); 223 db_symbol_values(sym, &name, valuep); 224 return (true); 225 } 226 227 bool 228 db_value_of_name_pcpu(const char *name, db_expr_t *valuep) 229 { 230 static char tmp[256]; 231 db_expr_t value; 232 c_db_sym_t sym; 233 int cpu; 234 235 if (db_cpu != -1) 236 cpu = db_cpu; 237 else 238 cpu = curcpu; 239 snprintf(tmp, sizeof(tmp), "pcpu_entry_%s", name); 240 sym = db_lookup(tmp); 241 if (sym == C_DB_SYM_NULL) 242 return (false); 243 db_symbol_values(sym, &name, &value); 244 if (value < DPCPU_START || value >= DPCPU_STOP) 245 return (false); 246 *valuep = (db_expr_t)((uintptr_t)value + dpcpu_off[cpu]); 247 return (true); 248 } 249 250 bool 251 db_value_of_name_vnet(const char *name, db_expr_t *valuep) 252 { 253 #ifdef VIMAGE 254 static char tmp[256]; 255 db_expr_t value; 256 c_db_sym_t sym; 257 struct vnet *vnet; 258 259 if (db_vnet != NULL) 260 vnet = db_vnet; 261 else 262 vnet = curvnet; 263 snprintf(tmp, sizeof(tmp), "vnet_entry_%s", name); 264 sym = db_lookup(tmp); 265 if (sym == C_DB_SYM_NULL) 266 return (false); 267 db_symbol_values(sym, &name, &value); 268 if (value < VNET_START || value >= VNET_STOP) 269 return (false); 270 *valuep = (db_expr_t)((uintptr_t)value + vnet->vnet_data_base); 271 return (true); 272 #else 273 return (false); 274 #endif 275 } 276 277 /* 278 * Lookup a symbol. 279 * If the symbol has a qualifier (e.g., ux:vm_map), 280 * then only the specified symbol table will be searched; 281 * otherwise, all symbol tables will be searched. 282 */ 283 static c_db_sym_t 284 db_lookup(const char *symstr) 285 { 286 c_db_sym_t sp; 287 register int i; 288 int symtab_start = 0; 289 int symtab_end = db_nsymtab; 290 register const char *cp; 291 292 /* 293 * Look for, remove, and remember any symbol table specifier. 294 */ 295 for (cp = symstr; *cp; cp++) { 296 if (*cp == ':') { 297 for (i = 0; i < db_nsymtab; i++) { 298 int n = strlen(db_symtabs[i].name); 299 300 if ( 301 n == (cp - symstr) && 302 strncmp(symstr, db_symtabs[i].name, n) == 0 303 ) { 304 symtab_start = i; 305 symtab_end = i + 1; 306 break; 307 } 308 } 309 if (i == db_nsymtab) { 310 db_error("invalid symbol table name"); 311 } 312 symstr = cp+1; 313 } 314 } 315 316 /* 317 * Look in the specified set of symbol tables. 318 * Return on first match. 319 */ 320 for (i = symtab_start; i < symtab_end; i++) { 321 sp = X_db_lookup(&db_symtabs[i], symstr); 322 if (sp) { 323 db_last_symtab = &db_symtabs[i]; 324 return sp; 325 } 326 } 327 return 0; 328 } 329 330 /* 331 * If true, check across symbol tables for multiple occurrences 332 * of a name. Might slow things down quite a bit. 333 */ 334 static volatile bool db_qualify_ambiguous_names = false; 335 336 /* 337 * Does this symbol name appear in more than one symbol table? 338 * Used by db_symbol_values to decide whether to qualify a symbol. 339 */ 340 static bool 341 db_symbol_is_ambiguous(c_db_sym_t sym) 342 { 343 const char *sym_name; 344 register int i; 345 register bool found_once = false; 346 347 if (!db_qualify_ambiguous_names) 348 return (false); 349 350 db_symbol_values(sym, &sym_name, 0); 351 for (i = 0; i < db_nsymtab; i++) { 352 if (X_db_lookup(&db_symtabs[i], sym_name)) { 353 if (found_once) 354 return (true); 355 found_once = true; 356 } 357 } 358 return (false); 359 } 360 361 /* 362 * Find the closest symbol to val, and return its name 363 * and the difference between val and the symbol found. 364 */ 365 c_db_sym_t 366 db_search_symbol(db_addr_t val, db_strategy_t strategy, db_expr_t *offp) 367 { 368 register 369 unsigned int diff; 370 size_t newdiff; 371 register int i; 372 c_db_sym_t ret = C_DB_SYM_NULL, sym; 373 374 newdiff = diff = ~0; 375 for (i = 0; i < db_nsymtab; i++) { 376 sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff); 377 if (newdiff < diff) { 378 db_last_symtab = &db_symtabs[i]; 379 diff = newdiff; 380 ret = sym; 381 } 382 } 383 *offp = diff; 384 return ret; 385 } 386 387 /* 388 * Return name and value of a symbol 389 */ 390 void 391 db_symbol_values(c_db_sym_t sym, const char **namep, db_expr_t *valuep) 392 { 393 db_expr_t value; 394 395 if (sym == DB_SYM_NULL) { 396 *namep = 0; 397 return; 398 } 399 400 X_db_symbol_values(db_last_symtab, sym, namep, &value); 401 402 if (db_symbol_is_ambiguous(sym)) 403 *namep = db_qualify(sym, db_last_symtab->name); 404 if (valuep) 405 *valuep = value; 406 } 407 408 409 /* 410 * Print a the closest symbol to value 411 * 412 * After matching the symbol according to the given strategy 413 * we print it in the name+offset format, provided the symbol's 414 * value is close enough (eg smaller than db_maxoff). 415 * We also attempt to print [filename:linenum] when applicable 416 * (eg for procedure names). 417 * 418 * If we could not find a reasonable name+offset representation, 419 * then we just print the value in hex. Small values might get 420 * bogus symbol associations, e.g. 3 might get some absolute 421 * value like _INCLUDE_VERSION or something, therefore we do 422 * not accept symbols whose value is "small" (and use plain hex). 423 */ 424 425 db_expr_t db_maxoff = 0x10000; 426 427 void 428 db_printsym(db_expr_t off, db_strategy_t strategy) 429 { 430 db_expr_t d; 431 char *filename; 432 const char *name; 433 db_expr_t value; 434 int linenum; 435 c_db_sym_t cursym; 436 437 cursym = db_search_symbol(off, strategy, &d); 438 db_symbol_values(cursym, &name, &value); 439 if (name == 0) 440 value = off; 441 if (value >= DB_SMALL_VALUE_MIN && value <= DB_SMALL_VALUE_MAX) { 442 db_printf("%+#lr", (long)off); 443 return; 444 } 445 if (name == 0 || d >= (unsigned long)db_maxoff) { 446 db_printf("%#lr", (unsigned long)off); 447 return; 448 } 449 #ifdef DDB_NUMSYM 450 db_printf("%#lr = %s", (unsigned long)off, name); 451 #else 452 db_printf("%s", name); 453 #endif 454 if (d) 455 db_printf("+%+#lr", (long)d); 456 if (strategy == DB_STGY_PROC) { 457 if (db_line_at_pc(cursym, &filename, &linenum, off)) 458 db_printf(" [%s:%d]", filename, linenum); 459 } 460 } 461 462 static bool 463 db_line_at_pc(c_db_sym_t sym, char **filename, int *linenum, db_expr_t pc) 464 { 465 return (X_db_line_at_pc(db_last_symtab, sym, filename, linenum, pc)); 466 } 467 468 bool 469 db_sym_numargs(c_db_sym_t sym, int *nargp, char **argnames) 470 { 471 return (X_db_sym_numargs(db_last_symtab, sym, nargp, argnames)); 472 } 473