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