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