sys/ddb/db_variables.c

   1 /*      $NetBSD: db_variables.c,v 1.41 2009/03/07 22:02:17 ad 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@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 1.41 2009/03/07 22:02:17 ad 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
  70 static int      db_rw_internal_variable(const struct db_variable *, db_expr_t *,
  71                     int);
  72 static int      db_find_variable(const struct db_variable **);
  73
  74 /* XXX must all be ints for sysctl. */
  75 const struct db_variable db_vars[] = {
  76         { "radix",      (void *)&db_radix,      db_rw_internal_variable, NULL },
  77         { "maxoff",     (void *)&db_maxoff,     db_rw_internal_variable, NULL },
  78         { "maxwidth",   (void *)&db_max_width,  db_rw_internal_variable, NULL },
  79         { "tabstops",   (void *)&db_tab_stop_width, db_rw_internal_variable, NULL },
  80         { "lines",      (void *)&db_max_line,   db_rw_internal_variable, NULL },
  81         { "onpanic",    (void *)&db_onpanic,    db_rw_internal_variable, NULL },
  82         { "fromconsole", (void *)&db_fromconsole, db_rw_internal_variable, NULL },
  83         { "tee_msgbuf", (void *)&db_tee_msgbuf, db_rw_internal_variable, NULL },
  84 };
  85 const struct db_variable * const db_evars = db_vars + sizeof(db_vars)/sizeof(db_vars[0]);
  86
  87 /*
  88  * ddb command line access to the DDB variables defined above.
  89  */
  90 static int
  91 db_rw_internal_variable(const struct db_variable *vp, db_expr_t *valp, int rw)
  92 {
  93
  94         if (rw == DB_VAR_GET)
  95                 *valp = *(int *)vp->valuep;
  96         else
  97                 *(int *)vp->valuep = *valp;
  98         return (0);
  99 }
 100
 101 /*
 102  * sysctl(3) access to the DDB variables defined above.
 103  */
 104 #ifdef _KERNEL
 105 SYSCTL_SETUP(sysctl_ddb_setup, "sysctl ddb subtree setup")
 106 {
 107
 108         sysctl_createv(clog, 0, NULL, NULL,
 109                        CTLFLAG_PERMANENT,
 110                        CTLTYPE_NODE, "ddb", NULL,
 111                        NULL, 0, NULL, 0,
 112                        CTL_DDB, CTL_EOL);
 113
 114         sysctl_createv(clog, 0, NULL, NULL,
 115                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 116                        CTLTYPE_INT, "radix",
 117                        SYSCTL_DESCR("Input and output radix"),
 118                        NULL, 0, &db_radix, 0,
 119                        CTL_DDB, DDBCTL_RADIX, CTL_EOL);
 120         sysctl_createv(clog, 0, NULL, NULL,
 121                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 122                        CTLTYPE_INT, "maxoff",
 123                        SYSCTL_DESCR("Maximum symbol offset"),
 124                        NULL, 0, &db_maxoff, 0,
 125                        CTL_DDB, DDBCTL_MAXOFF, CTL_EOL);
 126         sysctl_createv(clog, 0, NULL, NULL,
 127                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 128                        CTLTYPE_INT, "maxwidth",
 129                        SYSCTL_DESCR("Maximum output line width"),
 130                        NULL, 0, &db_max_width, 0,
 131                        CTL_DDB, DDBCTL_MAXWIDTH, CTL_EOL);
 132         sysctl_createv(clog, 0, NULL, NULL,
 133                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 134                        CTLTYPE_INT, "lines",
 135                        SYSCTL_DESCR("Number of display lines"),
 136                        NULL, 0, &db_max_line, 0,
 137                        CTL_DDB, DDBCTL_LINES, CTL_EOL);
 138         sysctl_createv(clog, 0, NULL, NULL,
 139                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 140                        CTLTYPE_INT, "tabstops",
 141                        SYSCTL_DESCR("Output tab width"),
 142                        NULL, 0, &db_tab_stop_width, 0,
 143                        CTL_DDB, DDBCTL_TABSTOPS, CTL_EOL);
 144         sysctl_createv(clog, 0, NULL, NULL,
 145                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 146                        CTLTYPE_INT, "onpanic",
 147                        SYSCTL_DESCR("Whether to enter ddb on a kernel panic"),
 148                        NULL, 0, &db_onpanic, 0,
 149                        CTL_DDB, DDBCTL_ONPANIC, CTL_EOL);
 150         sysctl_createv(clog, 0, NULL, NULL,
 151                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 152                        CTLTYPE_INT, "fromconsole",
 153                        SYSCTL_DESCR("Whether ddb can be entered from the "
 154                                     "console"),
 155                        NULL, 0, &db_fromconsole, 0,
 156                        CTL_DDB, DDBCTL_FROMCONSOLE, CTL_EOL);
 157         sysctl_createv(clog, 0, NULL, NULL,
 158                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 159                        CTLTYPE_INT, "tee_msgbuf",
 160                        SYSCTL_DESCR("Whether to tee ddb output to the msgbuf"),
 161                        NULL, 0, &db_tee_msgbuf, 0,
 162                        CTL_DDB, CTL_CREATE, CTL_EOL);
 163
 164         sysctl_createv(clog, 0, NULL, NULL,
 165                        CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
 166                        CTLTYPE_STRING, "commandonenter",
 167                        SYSCTL_DESCR("Command to be executed on each ddb enter"),
 168                        NULL, 0, &db_cmd_on_enter, DB_LINE_MAXLEN,
 169                        CTL_DDB, CTL_CREATE, CTL_EOL);
 170 }
 171 #endif  /* _KERNEL */
 172
 173 int
 174 db_find_variable(const struct db_variable **varp)
 175 {
 176         int     t;
 177         const struct db_variable *vp;
 178
 179         t = db_read_token();
 180         if (t == tIDENT) {
 181                 for (vp = db_vars; vp < db_evars; vp++) {
 182                         if (!strcmp(db_tok_string, vp->name)) {
 183                                 *varp = vp;
 184                                 return (1);
 185                         }
 186                 }
 187                 for (vp = db_regs; vp < db_eregs; vp++) {
 188                         if (!strcmp(db_tok_string, vp->name)) {
 189                                 *varp = vp;
 190                                 return (1);
 191                         }
 192                 }
 193         }
 194         db_error("Unknown variable\n");
 195         /*NOTREACHED*/
 196         return 0;
 197 }
 198
 199 int
 200 db_get_variable(db_expr_t *valuep)
 201 {
 202         const struct db_variable *vp;
 203
 204         if (!db_find_variable(&vp))
 205                 return (0);
 206
 207         db_read_variable(vp, valuep);
 208
 209         return (1);
 210 }
 211
 212 int
 213 db_set_variable(db_expr_t value)
 214 {
 215         const struct db_variable *vp;
 216
 217         if (!db_find_variable(&vp))
 218                 return (0);
 219
 220         db_write_variable(vp, &value);
 221
 222         return (1);
 223 }
 224
 225
 226 void
 227 db_read_variable(const struct db_variable *vp, db_expr_t *valuep)
 228 {
 229         int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
 230
 231         if (func == FCN_NULL)
 232                 *valuep = *(vp->valuep);
 233         else
 234                 (*func)(vp, valuep, DB_VAR_GET);
 235 }
 236
 237 void
 238 db_write_variable(const struct db_variable *vp, db_expr_t *valuep)
 239 {
 240         int (*func)(const struct db_variable *, db_expr_t *, int) = vp->fcn;
 241
 242         if (func == FCN_NULL)
 243                 *(vp->valuep) = *valuep;
 244         else
 245                 (*func)(vp, valuep, DB_VAR_SET);
 246 }
 247
 248 /*ARGSUSED*/
 249 void
 250 db_set_cmd(db_expr_t addr, bool have_addr,
 251     db_expr_t count, const char *modif)
 252 {
 253         db_expr_t       value;
 254         db_expr_t       old_value;
 255         const struct db_variable *vp = NULL;    /* XXX: GCC */
 256         int     t;
 257
 258         t = db_read_token();
 259         if (t != tDOLLAR) {
 260                 db_error("Unknown variable\n");
 261                 /*NOTREACHED*/
 262         }
 263         if (!db_find_variable(&vp)) {
 264                 db_error("Unknown variable\n");
 265                 /*NOTREACHED*/
 266         }
 267
 268         t = db_read_token();
 269         if (t != tEQ)
 270                 db_unread_token(t);
 271
 272         if (!db_expression(&value)) {
 273                 db_error("No value\n");
 274                 /*NOTREACHED*/
 275         }
 276         if (db_read_token() != tEOL) {
 277                 db_error("?\n");
 278                 /*NOTREACHED*/
 279         }
 280
 281         db_read_variable(vp, &old_value);
 282         db_printf("$%s\t\t%s = ", vp->name, db_num_to_str(old_value));
 283         db_printf("%s\n", db_num_to_str(value));
 284         db_write_variable(vp, &value);
 285 }