src/runtime/monitor.c

   1 /*
   2  * This software is part of the SBCL system. See the README file for
   3  * more information.
   4  *
   5  * This software is derived from the CMU CL system, which was
   6  * written at Carnegie Mellon University and released into the
   7  * public domain. The software is in the public domain and is
   8  * provided with absolutely no warranty. See the COPYING and CREDITS
   9  * files for more information.
  10  */
  11
  12 #include "sbcl.h"
  13
  14 #include <stdio.h>
  15 #include <sys/types.h>
  16 #include <stdlib.h>
  17 #include <setjmp.h>
  18 #include <sys/time.h>
  19 #ifndef LISP_FEATURE_WIN32
  20 #include <sys/resource.h>
  21 #endif
  22 #include <signal.h>
  23 #include <unistd.h>
  24
  25 #include "runtime.h"
  26 #include "parse.h"
  27 #include "vars.h"
  28
  29 /* Almost all of this file can be skipped if we're not supporting LDB. */
  30 #if defined(LISP_FEATURE_SB_LDB)
  31
  32 #include "print.h"
  33 #include "arch.h"
  34 #include "interr.h"
  35 #include "gc.h"
  36 #include "search.h"
  37 #include "purify.h"
  38 #include "globals.h"
  39 #include "lispregs.h"
  40 #include "interrupt.h"
  41 #include "thread.h"
  42 #include "genesis/static-symbols.h"
  43 #include "genesis/primitive-objects.h"
  44
  45
  46
  47 /* When we need to do command input, we use this stream, which is not
  48  * in general stdin, so that things will "work" (as well as being
  49  * thrown into ldb can be considered "working":-) even in a process
  50  * where standard input has been redirected to a file or pipe.
  51  *
  52  * (We could set up output to go to a special ldb_out stream for the
  53  * same reason, but there's been no pressure for that so far.)
  54  *
  55  * The enter-the-ldb-monitor function is responsible for setting up
  56  * this stream. */
  57 static FILE *ldb_in = 0;
  58 static int ldb_in_fd = -1;
  59
  60 typedef void cmd(char **ptr);
  61
  62 static cmd dump_cmd, print_cmd, quit_cmd, help_cmd;
  63 static cmd flush_cmd, search_cmd, regs_cmd, exit_cmd;
  64 static cmd print_context_cmd;
  65 static cmd backtrace_cmd, purify_cmd, catchers_cmd;
  66 static cmd grab_sigs_cmd;
  67 static cmd kill_cmd;
  68
  69 static struct cmd {
  70     char *cmd, *help;
  71     void (*fn)(char **ptr);
  72 } supported_cmds[] = {
  73     {"help", "Display this help information.", help_cmd},
  74     {"?", "(an alias for help)", help_cmd},
  75     {"backtrace", "Backtrace up to N frames.", backtrace_cmd},
  76     {"catchers", "Print a list of all the active catchers.", catchers_cmd},
  77     {"context", "Print interrupt context number I.", print_context_cmd},
  78     {"dump", "Dump memory starting at ADDRESS for COUNT words.", dump_cmd},
  79     {"d", "(an alias for dump)", dump_cmd},
  80     {"exit", "Exit this instance of the monitor.", exit_cmd},
  81     {"flush", "Flush all temp variables.", flush_cmd},
  82     /* (Classic CMU CL had a "gc" command here, which seems like a
  83      * reasonable idea, but the code was stale (incompatible with
  84      * gencgc) so I just flushed it. -- WHN 20000814 */
  85     {"grab-signals", "Set the signal handlers to call LDB.", grab_sigs_cmd},
  86     {"kill", "Kill ourself with signal number N (useful if running under gdb)",
  87      kill_cmd},
  88     {"purify", "Purify. (Caveat purifier!)", purify_cmd},
  89     {"print", "Print object at ADDRESS.", print_cmd},
  90     {"p", "(an alias for print)", print_cmd},
  91     {"quit", "Quit.", quit_cmd},
  92     {"regs", "Display current Lisp registers.", regs_cmd},
  93     {"search", "Search for TYPE starting at ADDRESS for a max of COUNT words.", search_cmd},
  94     {"s", "(an alias for search)", search_cmd},
  95     {NULL, NULL, NULL}
  96 };
  97
  98 static jmp_buf curbuf;
  99
 100 static int
 101 visible(unsigned char c)
 102 {
 103     if (c < ' ' || c > '~')
 104         return ' ';
 105     else
 106         return c;
 107 }
 108
 109 static void
 110 dump_cmd(char **ptr)
 111 {
 112     static char *lastaddr = 0;
 113     static int lastcount = 20;
 114
 115     char *addr = lastaddr;
 116     int count = lastcount, displacement;
 117
 118     if (more_p(ptr)) {
 119         addr = parse_addr(ptr);
 120
 121         if (more_p(ptr))
 122             count = parse_number(ptr);
 123     }
 124
 125     if (count == 0) {
 126         printf("COUNT must be non-zero.\n");
 127         return;
 128     }
 129
 130     lastcount = count;
 131
 132     if (count > 0)
 133         displacement = 4;
 134     else {
 135         displacement = -4;
 136         count = -count;
 137     }
 138
 139     while (count-- > 0) {
 140 #ifndef LISP_FEATURE_ALPHA
 141         printf("0x%08lX: ", (unsigned long) addr);
 142 #else
 143         printf("0x%08X: ", (u32) addr);
 144 #endif
 145         if (is_valid_lisp_addr((os_vm_address_t)addr)) {
 146 #ifndef LISP_FEATURE_ALPHA
 147             unsigned long *lptr = (unsigned long *)addr;
 148 #else
 149             u32 *lptr = (u32 *)addr;
 150 #endif
 151             unsigned short *sptr = (unsigned short *)addr;
 152             unsigned char *cptr = (unsigned char *)addr;
 153
 154             printf("0x%08lx   0x%04x 0x%04x   "
 155                    "0x%02x 0x%02x 0x%02x 0x%02x    "
 156                    "%c%c"
 157                    "%c%c\n",
 158                    lptr[0], sptr[0], sptr[1],
 159                    cptr[0], cptr[1], cptr[2], cptr[3],
 160                    visible(cptr[0]), visible(cptr[1]),
 161                    visible(cptr[2]), visible(cptr[3]));
 162         }
 163         else
 164             printf("invalid Lisp-level address\n");
 165
 166         addr += displacement;
 167     }
 168
 169     lastaddr = addr;
 170 }
 171
 172 static void
 173 print_cmd(char **ptr)
 174 {
 175     lispobj obj = parse_lispobj(ptr);
 176
 177     print(obj);
 178 }
 179
 180 static void
 181 kill_cmd(char **ptr)
 182 {
 183 #ifndef LISP_FEATURE_WIN32
 184     kill(getpid(), parse_number(ptr));
 185 #endif
 186 }
 187
 188 static void
 189 regs_cmd(char **ptr)
 190 {
 191     struct thread *thread=arch_os_get_current_thread();
 192
 193     printf("CSP\t=\t0x%08lx   ", (unsigned long)current_control_stack_pointer);
 194     printf("CFP\t=\t0x%08lx   ", (unsigned long)current_control_frame_pointer);
 195
 196 #ifdef reg_BSP
 197     printf("BSP\t=\t0x%08lx\n", (unsigned long)current_binding_stack_pointer);
 198 #else
 199     /* printf("BSP\t=\t0x%08lx\n",
 200            (unsigned long)SymbolValue(BINDING_STACK_POINTER)); */
 201     printf("\n");
 202 #endif
 203
 204 #ifdef LISP_FEATURE_GENCGC
 205     /* printf("DYNAMIC\t=\t0x%08lx\n", DYNAMIC_SPACE_START); */
 206 #else
 207     printf("STATIC\t=\t0x%08lx   ",
 208            (unsigned long)SymbolValue(STATIC_SPACE_FREE_POINTER, thread));
 209     printf("RDONLY\t=\t0x%08lx   ",
 210            (unsigned long)SymbolValue(READ_ONLY_SPACE_FREE_POINTER, thread));
 211     printf("DYNAMIC\t=\t0x%08lx\n", (unsigned long)current_dynamic_space);
 212 #endif
 213
 214 #ifdef reg_ALLOC
 215     printf("ALLOC\t=\t0x%08lx\n", (unsigned long)dynamic_space_free_pointer);
 216 #else
 217     printf("ALLOC\t=\t0x%08lx\n",
 218            (unsigned long)SymbolValue(ALLOCATION_POINTER, thread));
 219 #endif
 220
 221 #ifndef LISP_FEATURE_GENCGC
 222     printf("TRIGGER\t=\t0x%08lx\n", (unsigned long)current_auto_gc_trigger);
 223 #endif
 224 }
 225
 226 static void
 227 search_cmd(char **ptr)
 228 {
 229     static int lastval = 0, lastcount = 0;
 230     static lispobj *start = 0, *end = 0;
 231     int val, count;
 232     lispobj *addr, obj;
 233
 234     if (more_p(ptr)) {
 235         val = parse_number(ptr);
 236         if (val < 0 || val > 0xff) {
 237             printf("can only search for single bytes\n");
 238             return;
 239         }
 240         if (more_p(ptr)) {
 241             addr = (lispobj *)native_pointer((long)parse_addr(ptr));
 242             if (more_p(ptr)) {
 243                 count = parse_number(ptr);
 244             }
 245             else {
 246                 /* Specified value and address, but no count. Only one. */
 247                 count = -1;
 248             }
 249         }
 250         else {
 251             /* Specified a value, but no address, so search same range. */
 252             addr = start;
 253             count = lastcount;
 254         }
 255     }
 256     else {
 257         /* Specified nothing, search again for val. */
 258         val = lastval;
 259         addr = end;
 260         count = lastcount;
 261     }
 262
 263     lastval = val;
 264     start = end = addr;
 265     lastcount = count;
 266
 267     printf("searching for 0x%x at 0x%08lX\n", val, (unsigned long)end);
 268
 269     while (search_for_type(val, &end, &count)) {
 270         printf("found 0x%x at 0x%08lX:\n", val, (unsigned long)end);
 271         obj = *end;
 272         addr = end;
 273         end += 2;
 274         if (widetag_of(obj) == SIMPLE_FUN_HEADER_WIDETAG) {
 275             print((long)addr | FUN_POINTER_LOWTAG);
 276         } else if (lowtag_of(obj) == OTHER_IMMEDIATE_0_LOWTAG ||
 277                    lowtag_of(obj) == OTHER_IMMEDIATE_1_LOWTAG) {
 278             print((lispobj)addr | OTHER_POINTER_LOWTAG);
 279         } else {
 280             print((lispobj)addr);
 281         } if (count == -1) {
 282             return;
 283         }
 284     }
 285 }
 286
 287 /* (There used to be call_cmd() here, to call known-at-cold-init-time
 288  * Lisp functions from ldb, but it bitrotted and was deleted in
 289  * sbcl-0.7.5.1. See older CVS versions if you want to resuscitate
 290  * it.) */
 291
 292 static void
 293 flush_cmd(char **ptr)
 294 {
 295     flush_vars();
 296 }
 297
 298 static void
 299 quit_cmd(char **ptr)
 300 {
 301     char buf[10];
 302
 303     printf("Really quit? [y] ");
 304     fflush(stdout);
 305     fgets(buf, sizeof(buf), ldb_in);
 306     if (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')
 307         exit(1);
 308 }
 309
 310 static void
 311 help_cmd(char **ptr)
 312 {
 313     struct cmd *cmd;
 314
 315     for (cmd = supported_cmds; cmd->cmd != NULL; cmd++)
 316         if (cmd->help != NULL)
 317             printf("%s\t%s\n", cmd->cmd, cmd->help);
 318 }
 319
 320 static int done;
 321
 322 static void
 323 exit_cmd(char **ptr)
 324 {
 325     done = 1;
 326 }
 327
 328 static void
 329 purify_cmd(char **ptr)
 330 {
 331     purify(NIL, NIL);
 332 }
 333
 334 static void
 335 print_context(os_context_t *context)
 336 {
 337     int i;
 338
 339     for (i = 0; i < NREGS; i++) {
 340         printf("%s:\t", lisp_register_names[i]);
 341 #ifdef LISP_FEATURE_X86
 342         brief_print((lispobj)(*os_context_register_addr(context,
 343                                                         i*2)));
 344 #else
 345         brief_print((lispobj)(*os_context_register_addr(context,i)));
 346 #endif
 347     }
 348 #ifdef LISP_FEATURE_DARWIN
 349     printf("DAR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 41)));
 350     printf("DSISR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 42)));
 351 #endif
 352     printf("PC:\t\t  0x%08lx\n",
 353            (unsigned long)(*os_context_pc_addr(context)));
 354 }
 355
 356 static void
 357 print_context_cmd(char **ptr)
 358 {
 359     int free_ici;
 360     struct thread *thread=arch_os_get_current_thread();
 361
 362     free_ici = fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread));
 363
 364     if (more_p(ptr)) {
 365         int index;
 366
 367         index = parse_number(ptr);
 368
 369         if ((index >= 0) && (index < free_ici)) {
 370             printf("There are %d interrupt contexts.\n", free_ici);
 371             printf("printing context %d\n", index);
 372             print_context(thread->interrupt_contexts[index]);
 373         } else {
 374             printf("There aren't that many/few contexts.\n");
 375             printf("There are %d interrupt contexts.\n", free_ici);
 376         }
 377     } else {
 378         if (free_ici == 0)
 379             printf("There are no interrupt contexts!\n");
 380         else {
 381             printf("There are %d interrupt contexts.\n", free_ici);
 382             printf("printing context %d\n", free_ici - 1);
 383             print_context(thread->interrupt_contexts[free_ici - 1]);
 384         }
 385     }
 386 }
 387
 388 static void
 389 backtrace_cmd(char **ptr)
 390 {
 391     void backtrace(int frames);
 392     int n;
 393
 394     if (more_p(ptr))
 395         n = parse_number(ptr);
 396     else
 397         n = 100;
 398
 399     printf("Backtrace:\n");
 400     backtrace(n);
 401 }
 402
 403 static void
 404 catchers_cmd(char **ptr)
 405 {
 406     struct catch_block *catch;
 407     struct thread *thread=arch_os_get_current_thread();
 408
 409     catch = (struct catch_block *)SymbolValue(CURRENT_CATCH_BLOCK,thread);
 410
 411     if (catch == NULL)
 412         printf("There are no active catchers!\n");
 413     else {
 414         while (catch != NULL) {
 415             printf("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\t"
 416                    "code: 0x%08lX\n\tentry: 0x%08lX\n\ttag: ",
 417                    (unsigned long)catch,
 418                    (unsigned long)(catch->current_uwp),
 419                    (unsigned long)(catch->current_cont),
 420 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 421                    (unsigned long)component_ptr_from_pc((void*)catch->entry_pc)
 422                        + OTHER_POINTER_LOWTAG,
 423 #else
 424                    (unsigned long)(catch->current_code),
 425 #endif
 426                    (unsigned long)(catch->entry_pc));
 427             brief_print((lispobj)catch->tag);
 428             catch = catch->previous_catch;
 429         }
 430     }
 431 }
 432
 433 static void
 434 grab_sigs_cmd(char **ptr)
 435 {
 436     extern void sigint_init(void);
 437
 438     printf("Grabbing signals.\n");
 439     sigint_init();
 440 }
 441
 442 static void
 443 sub_monitor(void)
 444 {
 445     struct cmd *cmd, *found;
 446     char buf[256];
 447     char *line, *ptr, *token;
 448     int ambig;
 449
 450     if (!ldb_in) {
 451 #ifndef LISP_FEATURE_WIN32
 452         ldb_in = fopen("/dev/tty","r+");
 453 #else
 454         ldb_in = stdin;
 455 #endif
 456         ldb_in_fd = fileno(ldb_in);
 457     }
 458
 459     while (!done) {
 460         printf("ldb> ");
 461         fflush(stdout);
 462         line = fgets(buf, sizeof(buf), ldb_in);
 463         if (line == NULL) {
 464             exit(1);
 465         }
 466         ptr = line;
 467         if ((token = parse_token(&ptr)) == NULL)
 468             continue;
 469         ambig = 0;
 470         found = NULL;
 471         for (cmd = supported_cmds; cmd->cmd != NULL; cmd++) {
 472             if (strcmp(token, cmd->cmd) == 0) {
 473                 found = cmd;
 474                 ambig = 0;
 475                 break;
 476             }
 477             else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
 478                 if (found)
 479                     ambig = 1;
 480                 else
 481                     found = cmd;
 482             }
 483         }
 484         if (ambig)
 485             printf("``%s'' is ambiguous.\n", token);
 486         else if (found == NULL)
 487             printf("unknown command: ``%s''\n", token);
 488         else {
 489             reset_printer();
 490             (*found->fn)(&ptr);
 491         }
 492     }
 493 }
 494
 495 void
 496 ldb_monitor()
 497 {
 498     jmp_buf oldbuf;
 499
 500     bcopy(curbuf, oldbuf, sizeof(oldbuf));
 501
 502     printf("Welcome to LDB, a low-level debugger for the Lisp runtime environment.\n");
 503
 504     setjmp(curbuf);
 505
 506     sub_monitor();
 507
 508     done = 0;
 509
 510     bcopy(oldbuf, curbuf, sizeof(curbuf));
 511 }
 512
 513 void
 514 throw_to_monitor()
 515 {
 516     longjmp(curbuf, 1);
 517 }
 518
 519 #endif /* defined(LISP_FEATURE_SB_LDB) */
 520
 521 /* what we do when things go badly wrong at a low level */
 522 void
 523 monitor_or_something()
 524 {
 525 #if defined(LISP_FEATURE_SB_LDB)
 526     ldb_monitor();
 527 #else
 528      fprintf(stderr,
 529 "The system is too badly corrupted or confused to continue at the Lisp\n\
 530 level. If the system had been compiled with the SB-LDB feature, we'd drop\n\
 531 into the LDB low-level debugger now. But there's no LDB in this build, so\n\
 532 we can't really do anything but just exit, sorry.\n");
 533     exit(1);
 534 #endif
 535 }