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 * $FreeBSD: src/sys/ddb/db_sym.c,v 1.32 1999/08/28 00:41:10 peter Exp $ 27 * $DragonFly: src/sys/ddb/db_sym.c,v 1.2 2003/06/17 04:28:20 dillon Exp $ 28 */ 29 30 /* 31 * Author: David B. Golub, Carnegie Mellon University 32 * Date: 7/90 33 */ 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 37 #include <ddb/ddb.h> 38 #include <ddb/db_sym.h> 39 40 /* 41 * Multiple symbol tables 42 */ 43 #ifndef MAXNOSYMTABS 44 #define MAXNOSYMTABS 3 /* mach, ux, emulator */ 45 #endif 46 47 static db_symtab_t db_symtabs[MAXNOSYMTABS] = {{0,},}; 48 static int db_nsymtab = 0; 49 50 static db_symtab_t *db_last_symtab; /* where last symbol was found */ 51 52 static c_db_sym_t db_lookup __P(( const char *symstr)); 53 static char *db_qualify __P((c_db_sym_t sym, char *symtabname)); 54 static boolean_t db_symbol_is_ambiguous __P((c_db_sym_t sym)); 55 static boolean_t db_line_at_pc __P((c_db_sym_t, char **, int *, 56 db_expr_t)); 57 58 /* 59 * Add symbol table, with given name, to list of symbol tables. 60 */ 61 void 62 db_add_symbol_table(start, end, name, ref) 63 char *start; 64 char *end; 65 char *name; 66 char *ref; 67 { 68 if (db_nsymtab >= MAXNOSYMTABS) { 69 printf ("No slots left for %s symbol table", name); 70 panic ("db_sym.c: db_add_symbol_table"); 71 } 72 73 db_symtabs[db_nsymtab].start = start; 74 db_symtabs[db_nsymtab].end = end; 75 db_symtabs[db_nsymtab].name = name; 76 db_symtabs[db_nsymtab].private = ref; 77 db_nsymtab++; 78 } 79 80 /* 81 * db_qualify("vm_map", "ux") returns "unix:vm_map". 82 * 83 * Note: return value points to static data whose content is 84 * overwritten by each call... but in practice this seems okay. 85 */ 86 static char * 87 db_qualify(sym, symtabname) 88 c_db_sym_t sym; 89 register char *symtabname; 90 { 91 const char *symname; 92 static char tmp[256]; 93 94 db_symbol_values(sym, &symname, 0); 95 snprintf(tmp, sizeof(tmp), "%s:%s", symtabname, symname); 96 return tmp; 97 } 98 99 100 boolean_t 101 db_eqname(src, dst, c) 102 const char *src; 103 const char *dst; 104 int c; 105 { 106 if (!strcmp(src, dst)) 107 return (TRUE); 108 if (src[0] == c) 109 return (!strcmp(src+1,dst)); 110 return (FALSE); 111 } 112 113 boolean_t 114 db_value_of_name(name, valuep) 115 const char *name; 116 db_expr_t *valuep; 117 { 118 c_db_sym_t sym; 119 120 sym = db_lookup(name); 121 if (sym == C_DB_SYM_NULL) 122 return (FALSE); 123 db_symbol_values(sym, &name, valuep); 124 return (TRUE); 125 } 126 127 128 /* 129 * Lookup a symbol. 130 * If the symbol has a qualifier (e.g., ux:vm_map), 131 * then only the specified symbol table will be searched; 132 * otherwise, all symbol tables will be searched. 133 */ 134 static c_db_sym_t 135 db_lookup(symstr) 136 const char *symstr; 137 { 138 c_db_sym_t sp; 139 register int i; 140 int symtab_start = 0; 141 int symtab_end = db_nsymtab; 142 register const char *cp; 143 144 /* 145 * Look for, remove, and remember any symbol table specifier. 146 */ 147 for (cp = symstr; *cp; cp++) { 148 if (*cp == ':') { 149 for (i = 0; i < db_nsymtab; i++) { 150 int n = strlen(db_symtabs[i].name); 151 152 if ( 153 n == (cp - symstr) && 154 strncmp(symstr, db_symtabs[i].name, n) == 0 155 ) { 156 symtab_start = i; 157 symtab_end = i + 1; 158 break; 159 } 160 } 161 if (i == db_nsymtab) { 162 db_error("invalid symbol table name"); 163 } 164 symstr = cp+1; 165 } 166 } 167 168 /* 169 * Look in the specified set of symbol tables. 170 * Return on first match. 171 */ 172 for (i = symtab_start; i < symtab_end; i++) { 173 sp = X_db_lookup(&db_symtabs[i], symstr); 174 if (sp) { 175 db_last_symtab = &db_symtabs[i]; 176 return sp; 177 } 178 } 179 return 0; 180 } 181 182 /* 183 * If TRUE, check across symbol tables for multiple occurrences 184 * of a name. Might slow things down quite a bit. 185 */ 186 static volatile boolean_t db_qualify_ambiguous_names = FALSE; 187 188 /* 189 * Does this symbol name appear in more than one symbol table? 190 * Used by db_symbol_values to decide whether to qualify a symbol. 191 */ 192 static boolean_t 193 db_symbol_is_ambiguous(sym) 194 c_db_sym_t sym; 195 { 196 const char *sym_name; 197 register int i; 198 register 199 boolean_t found_once = FALSE; 200 201 if (!db_qualify_ambiguous_names) 202 return FALSE; 203 204 db_symbol_values(sym, &sym_name, 0); 205 for (i = 0; i < db_nsymtab; i++) { 206 if (X_db_lookup(&db_symtabs[i], sym_name)) { 207 if (found_once) 208 return TRUE; 209 found_once = TRUE; 210 } 211 } 212 return FALSE; 213 } 214 215 /* 216 * Find the closest symbol to val, and return its name 217 * and the difference between val and the symbol found. 218 */ 219 c_db_sym_t 220 db_search_symbol( val, strategy, offp) 221 register db_addr_t val; 222 db_strategy_t strategy; 223 db_expr_t *offp; 224 { 225 register 226 unsigned int diff; 227 size_t newdiff; 228 register int i; 229 c_db_sym_t ret = C_DB_SYM_NULL, sym; 230 231 newdiff = diff = ~0; 232 db_last_symtab = 0; 233 for (i = 0; i < db_nsymtab; i++) { 234 sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff); 235 if (newdiff < diff) { 236 db_last_symtab = &db_symtabs[i]; 237 diff = newdiff; 238 ret = sym; 239 } 240 } 241 *offp = diff; 242 return ret; 243 } 244 245 /* 246 * Return name and value of a symbol 247 */ 248 void 249 db_symbol_values(sym, namep, valuep) 250 c_db_sym_t sym; 251 const char **namep; 252 db_expr_t *valuep; 253 { 254 db_expr_t value; 255 256 if (sym == DB_SYM_NULL) { 257 *namep = 0; 258 return; 259 } 260 261 X_db_symbol_values(db_last_symtab, sym, namep, &value); 262 263 if (db_symbol_is_ambiguous(sym)) 264 *namep = db_qualify(sym, db_last_symtab->name); 265 if (valuep) 266 *valuep = value; 267 } 268 269 270 /* 271 * Print a the closest symbol to value 272 * 273 * After matching the symbol according to the given strategy 274 * we print it in the name+offset format, provided the symbol's 275 * value is close enough (eg smaller than db_maxoff). 276 * We also attempt to print [filename:linenum] when applicable 277 * (eg for procedure names). 278 * 279 * If we could not find a reasonable name+offset representation, 280 * then we just print the value in hex. Small values might get 281 * bogus symbol associations, e.g. 3 might get some absolute 282 * value like _INCLUDE_VERSION or something, therefore we do 283 * not accept symbols whose value is "small" (and use plain hex). 284 */ 285 286 db_expr_t db_maxoff = 0x10000; 287 288 void 289 db_printsym(off, strategy) 290 db_expr_t off; 291 db_strategy_t strategy; 292 { 293 db_expr_t d; 294 char *filename; 295 const char *name; 296 db_expr_t value; 297 int linenum; 298 c_db_sym_t cursym; 299 300 cursym = db_search_symbol(off, strategy, &d); 301 db_symbol_values(cursym, &name, &value); 302 if (name == 0) 303 value = off; 304 if (value >= DB_SMALL_VALUE_MIN && value <= DB_SMALL_VALUE_MAX) { 305 db_printf("%+#lr", (long)off); 306 return; 307 } 308 if (name == 0 || d >= (unsigned long)db_maxoff) { 309 db_printf("%#lr", (unsigned long)off); 310 return; 311 } 312 db_printf("%s", name); 313 if (d) 314 db_printf("+%+#lr", (long)d); 315 if (strategy == DB_STGY_PROC) { 316 if (db_line_at_pc(cursym, &filename, &linenum, off)) 317 db_printf(" [%s:%d]", filename, linenum); 318 } 319 } 320 321 static boolean_t 322 db_line_at_pc( sym, filename, linenum, pc) 323 c_db_sym_t sym; 324 char **filename; 325 int *linenum; 326 db_expr_t pc; 327 { 328 return X_db_line_at_pc( db_last_symtab, sym, filename, linenum, pc); 329 } 330 331 int 332 db_sym_numargs(sym, nargp, argnames) 333 c_db_sym_t sym; 334 int *nargp; 335 char **argnames; 336 { 337 return X_db_sym_numargs(db_last_symtab, sym, nargp, argnames); 338 } 339