1 /* $NetBSD: db_variables.c,v 1.47 2020/03/10 15:58:37 christos 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 (at) 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_variables.c,v 1.47 2020/03/10 15:58:37 christos Exp $"); 31 32 #ifdef _KERNEL_OPT 33 #include "opt_ddbparam.h" 34 #endif 35 36 #include <sys/param.h> 37 #include <sys/proc.h> 38 #include <uvm/uvm_extern.h> 39 #include <sys/sysctl.h> 40 41 #include <ddb/ddb.h> 42 #include <ddb/ddbvar.h> 43 44 /* 45 * If this is non-zero, the DDB will be entered when the system 46 * panics. Initialize it so that it's patchable. 47 */ 48 #ifndef DDB_ONPANIC 49 #define DDB_ONPANIC 1 50 #endif 51 int db_onpanic = DDB_ONPANIC; 52 53 /* 54 * Can DDB can be entered from the console? 55 */ 56 #ifndef DDB_FROMCONSOLE 57 #define DDB_FROMCONSOLE 1 58 #endif 59 int db_fromconsole = DDB_FROMCONSOLE; 60 61 /* 62 * Output DDB output to the message buffer? 63 */ 64 #ifndef DDB_TEE_MSGBUF 65 #define DDB_TEE_MSGBUF 0 66 #endif 67 int db_tee_msgbuf = DDB_TEE_MSGBUF; 68 69 #ifndef DDB_PANICSTACKFRAMES 70 #define DDB_PANICSTACKFRAMES 65535 71 #endif 72 int db_panicstackframes = DDB_PANICSTACKFRAMES; 73 74 #ifndef DDB_DUMPSTACK 75 #define DDB_DUMPSTACK 1 76 #endif 77 int db_dumpstack = DDB_DUMPSTACK; 78 79 static int db_rw_internal_variable(const struct db_variable *, db_expr_t *, 80 int); 81 static int db_find_variable(const struct db_variable **); 82 83 /* XXX must all be ints for sysctl. */ 84 const struct db_variable db_vars[] = { 85 { 86 .name = "fromconsole", 87 .valuep = &db_fromconsole, 88 .fcn = db_rw_internal_variable, 89 .modif = NULL, 90 }, 91 { 92 .name = "maxoff", 93 .valuep = &db_maxoff, 94 .fcn = db_rw_internal_variable, 95 .modif = NULL, 96 }, 97 { 98 .name = "maxwidth", 99 .valuep = &db_max_width, 100 .fcn = db_rw_internal_variable, 101 .modif = NULL, 102 }, 103 { 104 .name = "lines", 105 .valuep = &db_max_line, 106 .fcn = db_rw_internal_variable, 107 .modif = NULL, 108 }, 109 { 110 .name = "onpanic", 111 .valuep = &db_onpanic, 112 .fcn = db_rw_internal_variable, 113 .modif = NULL, 114 }, 115 { 116 .name = "panicstackframes", 117 .valuep = &db_panicstackframes, 118 .fcn = db_rw_internal_variable, 119 .modif = NULL, 120 }, 121 { 122 .name = "dumpstack", 123 .valuep = &db_dumpstack, 124 .fcn = db_rw_internal_variable, 125 .modif = NULL, 126 }, 127 { 128 .name = "radix", 129 .valuep = &db_radix, 130 .fcn = db_rw_internal_variable, 131 .modif = NULL, 132 }, 133 { 134 .name = "tabstops", 135 .valuep = &db_tab_stop_width, 136 .fcn = db_rw_internal_variable, 137 .modif = NULL, 138 }, 139 { 140 .name = "tee_msgbuf", 141 .valuep = &db_tee_msgbuf, 142 .fcn = db_rw_internal_variable, 143 .modif = NULL, 144 }, 145 }; 146 const struct db_variable * const db_evars = db_vars + __arraycount(db_vars); 147 148 /* 149 * ddb command line access to the DDB variables defined above. 150 */ 151 static int 152 db_rw_internal_variable(const struct db_variable *vp, db_expr_t *valp, int rw) 153 { 154 155 if (rw == DB_VAR_GET) 156 *valp = *(int *)vp->valuep; 157 else 158 *(int *)vp->valuep = *valp; 159 return (0); 160 } 161 162 /* 163 * sysctl(3) access to the DDB variables defined above. 164 */ 165 #ifdef _KERNEL 166 SYSCTL_SETUP(sysctl_ddb_setup, "sysctl ddb subtree setup") 167 { 168 169 sysctl_createv(clog, 0, NULL, NULL, 170 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 171 CTLTYPE_INT, "radix", 172 SYSCTL_DESCR("Input and output radix"), 173 NULL, 0, &db_radix, 0, 174 CTL_DDB, DDBCTL_RADIX, CTL_EOL); 175 sysctl_createv(clog, 0, NULL, NULL, 176 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 177 CTLTYPE_INT, "maxoff", 178 SYSCTL_DESCR("Maximum symbol offset"), 179 NULL, 0, &db_maxoff, 0, 180 CTL_DDB, DDBCTL_MAXOFF, CTL_EOL); 181 sysctl_createv(clog, 0, NULL, NULL, 182 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 183 CTLTYPE_INT, "maxwidth", 184 SYSCTL_DESCR("Maximum output line width"), 185 NULL, 0, &db_max_width, 0, 186 CTL_DDB, DDBCTL_MAXWIDTH, CTL_EOL); 187 sysctl_createv(clog, 0, NULL, NULL, 188 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 189 CTLTYPE_INT, "lines", 190 SYSCTL_DESCR("Number of display lines"), 191 NULL, 0, &db_max_line, 0, 192 CTL_DDB, DDBCTL_LINES, CTL_EOL); 193 sysctl_createv(clog, 0, NULL, NULL, 194 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 195 CTLTYPE_INT, "tabstops", 196 SYSCTL_DESCR("Output tab width"), 197 NULL, 0, &db_tab_stop_width, 0, 198 CTL_DDB, DDBCTL_TABSTOPS, CTL_EOL); 199 sysctl_createv(clog, 0, NULL, NULL, 200 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 201 CTLTYPE_INT, "onpanic", 202 SYSCTL_DESCR("Whether to enter ddb on a kernel panic"), 203 NULL, 0, &db_onpanic, 0, 204 CTL_DDB, DDBCTL_ONPANIC, CTL_EOL); 205 sysctl_createv(clog, 0, NULL, NULL, 206 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 207 CTLTYPE_INT, "fromconsole", 208 SYSCTL_DESCR("Whether ddb can be entered from the " 209 "console"), 210 NULL, 0, &db_fromconsole, 0, 211 CTL_DDB, DDBCTL_FROMCONSOLE, CTL_EOL); 212 sysctl_createv(clog, 0, NULL, NULL, 213 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 214 CTLTYPE_INT, "tee_msgbuf", 215 SYSCTL_DESCR("Whether to tee ddb output to the msgbuf"), 216 NULL, 0, &db_tee_msgbuf, 0, 217 CTL_DDB, CTL_CREATE, CTL_EOL); 218 sysctl_createv(clog, 0, NULL, NULL, 219 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 220 CTLTYPE_STRING, "commandonenter", 221 SYSCTL_DESCR("Command to be executed on each ddb enter"), 222 NULL, 0, db_cmd_on_enter, DB_LINE_MAXLEN, 223 CTL_DDB, CTL_CREATE, CTL_EOL); 224 sysctl_createv(clog, 0, NULL, NULL, 225 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 226 CTLTYPE_INT, "panicstackframes", 227 SYSCTL_DESCR("Number of stack frames to print on panic"), 228 NULL, 0, &db_panicstackframes, 0, 229 CTL_DDB, CTL_CREATE, CTL_EOL); 230 sysctl_createv(clog, 0, NULL, NULL, 231 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 232 CTLTYPE_INT, "dumpstack", 233 SYSCTL_DESCR("On panic print stack trace"), 234 NULL, 0, &db_dumpstack, 0, 235 CTL_DDB, CTL_CREATE, CTL_EOL); 236 } 237 #endif /* _KERNEL */ 238 239 int 240 db_find_variable(const struct db_variable **varp) 241 { 242 int t; 243 const struct db_variable *vp; 244 245 t = db_read_token(); 246 if (t == tIDENT) { 247 for (vp = db_vars; vp < db_evars; vp++) { 248 if (!strcmp(db_tok_string, vp->name)) { 249 *varp = vp; 250 return (1); 251 } 252 } 253 #ifdef _KERNEL 254 for (vp = db_regs; vp < db_eregs; vp++) { 255 if (!strcmp(db_tok_string, vp->name)) { 256 *varp = vp; 257 return (1); 258 } 259 } 260 #endif 261 } 262 db_error("Unknown variable\n"); 263 /*NOTREACHED*/ 264 return 0; 265 } 266 267 int 268 db_get_variable(db_expr_t *valuep) 269 { 270 const struct db_variable *vp; 271 272 if (!db_find_variable(&vp)) 273 return (0); 274 275 db_read_variable(vp, valuep); 276 277 return (1); 278 } 279 280 int 281 db_set_variable(db_expr_t value) 282 { 283 const struct db_variable *vp; 284 285 if (!db_find_variable(&vp)) 286 return (0); 287 288 db_write_variable(vp, &value); 289 290 return (1); 291 } 292 293 294 void 295 db_read_variable(const struct db_variable *vp, db_expr_t *valuep) 296 { 297 int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn; 298 299 if (func == FCN_NULL) 300 *valuep = *(db_expr_t *)vp->valuep; 301 else 302 (*func)(vp, valuep, DB_VAR_GET); 303 } 304 305 void 306 db_write_variable(const struct db_variable *vp, db_expr_t *valuep) 307 { 308 int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn; 309 310 if (func == FCN_NULL) 311 *(db_expr_t *)vp->valuep = *valuep; 312 else 313 (*func)(vp, valuep, DB_VAR_SET); 314 } 315 316 /*ARGSUSED*/ 317 void 318 db_set_cmd(db_expr_t addr, bool have_addr, 319 db_expr_t count, const char *modif) 320 { 321 db_expr_t value; 322 db_expr_t old_value; 323 const struct db_variable *vp = NULL; /* XXX: GCC */ 324 int t; 325 326 t = db_read_token(); 327 if (t != tDOLLAR) { 328 db_error("Unknown variable\n"); 329 /*NOTREACHED*/ 330 } 331 if (!db_find_variable(&vp)) { 332 db_error("Unknown variable\n"); 333 /*NOTREACHED*/ 334 } 335 336 t = db_read_token(); 337 if (t != tEQ) 338 db_unread_token(t); 339 340 if (!db_expression(&value)) { 341 db_error("No value\n"); 342 /*NOTREACHED*/ 343 } 344 if (db_read_token() != tEOL) { 345 db_error("?\n"); 346 /*NOTREACHED*/ 347 } 348 349 db_read_variable(vp, &old_value); 350 db_printf("$%s\t\t%s = ", vp->name, db_num_to_str(old_value)); 351 db_printf("%s\n", db_num_to_str(value)); 352 db_write_variable(vp, &value); 353 } 354
Indexes created Sat Sep 20 22:09:52 GMT 2025