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     int force = 0;
 118
 119     if (more_p(ptr)) {
 120         if (!strncmp(*ptr, "-f ", 3)) {
 121           force = 1;
 122           *ptr += 3;
 123         }
 124         addr = parse_addr(ptr, !force);
 125
 126         if (more_p(ptr))
 127             count = parse_number(ptr);
 128     }
 129
 130     if (count == 0) {
 131         printf("COUNT must be non-zero.\n");
 132         return;
 133     }
 134
 135     lastcount = count;
 136
 137     if (count > 0)
 138         displacement = N_WORD_BYTES;
 139     else {
 140         displacement = -N_WORD_BYTES;
 141         count = -count;
 142     }
 143
 144     while (count-- > 0) {
 145 #ifndef LISP_FEATURE_ALPHA
 146         printf("%p: ", (os_vm_address_t) addr);
 147 #else
 148         printf("0x%08X: ", (u32) addr);
 149 #endif
 150         if (force || is_valid_lisp_addr((os_vm_address_t)addr)) {
 151 #ifndef LISP_FEATURE_ALPHA
 152             unsigned long *lptr = (unsigned long *)addr;
 153 #else
 154             u32 *lptr = (u32 *)addr;
 155 #endif
 156             unsigned char *cptr = (unsigned char *)addr;
 157
 158 #if N_WORD_BYTES == 8
 159             printf("0x%016lx | %c%c%c%c%c%c%c%c\n",
 160                    lptr[0],
 161                    visible(cptr[0]), visible(cptr[1]),
 162                    visible(cptr[2]), visible(cptr[3]),
 163                    visible(cptr[4]), visible(cptr[5]),
 164                    visible(cptr[6]), visible(cptr[7]));
 165 #else
 166             unsigned short *sptr = (unsigned short *)addr;
 167             printf("0x%08lx   0x%04x 0x%04x   "
 168                    "0x%02x 0x%02x 0x%02x 0x%02x    "
 169                    "%c%c"
 170                    "%c%c\n",
 171                    lptr[0], sptr[0], sptr[1],
 172                    cptr[0], cptr[1], cptr[2], cptr[3],
 173                    visible(cptr[0]), visible(cptr[1]),
 174                    visible(cptr[2]), visible(cptr[3]));
 175 #endif
 176         }
 177         else
 178             printf("invalid Lisp-level address\n");
 179
 180         addr += displacement;
 181     }
 182
 183     lastaddr = addr;
 184 }
 185
 186 static void
 187 print_cmd(char **ptr)
 188 {
 189     lispobj obj = parse_lispobj(ptr);
 190
 191     print(obj);
 192 }
 193
 194 static void
 195 kill_cmd(char **ptr)
 196 {
 197 #ifndef LISP_FEATURE_WIN32
 198     kill(getpid(), parse_number(ptr));
 199 #endif
 200 }
 201
 202 static void
 203 regs_cmd(char **ptr)
 204 {
 205     struct thread __attribute__((unused)) *thread=arch_os_get_current_thread();
 206
 207     printf("CSP\t=\t%p   ", access_control_stack_pointer(thread));
 208 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
 209     printf("CFP\t=\t%p   ", access_control_frame_pointer(thread));
 210 #endif
 211
 212 #ifdef reg_BSP
 213     printf("BSP\t=\t%p\n", get_binding_stack_pointer(thread));
 214 #else
 215     /* printf("BSP\t=\t%p\n", (void*)SymbolValue(BINDING_STACK_POINTER)); */
 216     printf("\n");
 217 #endif
 218
 219 #ifdef LISP_FEATURE_GENCGC
 220     /* printf("DYNAMIC\t=\t%p\n", (void*)DYNAMIC_SPACE_START); */
 221 #else
 222     printf("STATIC\t=\t%p   ",
 223            (void*)SymbolValue(STATIC_SPACE_FREE_POINTER, thread));
 224     printf("RDONLY\t=\t%p   ",
 225            (void*)SymbolValue(READ_ONLY_SPACE_FREE_POINTER, thread));
 226     printf("DYNAMIC\t=\t%p\n", (void*)current_dynamic_space);
 227 #endif
 228
 229 #ifdef reg_ALLOC
 230     printf("ALLOC\t=\t%p\n", (void*)dynamic_space_free_pointer);
 231 #else
 232     printf("ALLOC\t=\t%p\n", (void*)SymbolValue(ALLOCATION_POINTER, thread));
 233 #endif
 234
 235 #ifndef LISP_FEATURE_GENCGC
 236     printf("TRIGGER\t=\t%p\n", (void*)current_auto_gc_trigger);
 237 #endif
 238 }
 239
 240 static void
 241 search_cmd(char **ptr)
 242 {
 243     static int lastval = 0, lastcount = 0;
 244     static lispobj *start = 0, *end = 0;
 245     int val, count;
 246     lispobj *addr, obj;
 247
 248     if (more_p(ptr)) {
 249         val = parse_number(ptr);
 250         if (val < 0 || val > 0xff) {
 251             printf("can only search for single bytes\n");
 252             return;
 253         }
 254         if (more_p(ptr)) {
 255             addr = native_pointer((uword_t)parse_addr(ptr, 1));
 256             if (more_p(ptr)) {
 257                 count = parse_number(ptr);
 258             }
 259             else {
 260                 /* Specified value and address, but no count. Only one. */
 261                 count = -1;
 262             }
 263         }
 264         else {
 265             /* Specified a value, but no address, so search same range. */
 266             addr = start;
 267             count = lastcount;
 268         }
 269     }
 270     else {
 271         /* Specified nothing, search again for val. */
 272         val = lastval;
 273         addr = end;
 274         count = lastcount;
 275     }
 276
 277     lastval = val;
 278     start = end = addr;
 279     lastcount = count;
 280
 281     printf("searching for 0x%x at %p\n", val, (void*)(uword_t)end);
 282
 283     while (search_for_type(val, &end, &count)) {
 284         printf("found 0x%x at %p:\n", val, (void*)(uword_t)end);
 285         obj = *end;
 286         addr = end;
 287         end += 2;
 288         if (widetag_of(obj) == SIMPLE_FUN_HEADER_WIDETAG) {
 289             print((uword_t)addr | FUN_POINTER_LOWTAG);
 290         } else if (other_immediate_lowtag_p(obj)) {
 291             print((lispobj)addr | OTHER_POINTER_LOWTAG);
 292         } else {
 293             print((lispobj)addr);
 294         } if (count == -1) {
 295             return;
 296         }
 297     }
 298 }
 299
 300 /* (There used to be call_cmd() here, to call known-at-cold-init-time
 301  * Lisp functions from ldb, but it bitrotted and was deleted in
 302  * sbcl-0.7.5.1. See older CVS versions if you want to resuscitate
 303  * it.) */
 304
 305 static void
 306 flush_cmd(char **ptr)
 307 {
 308     flush_vars();
 309 }
 310
 311 static void
 312 quit_cmd(char **ptr)
 313 {
 314     char buf[10];
 315
 316     printf("Really quit? [y] ");
 317     fflush(stdout);
 318     if (fgets(buf, sizeof(buf), ldb_in)) {
 319         if (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')
 320             exit(1);
 321     } else {
 322         printf("\nUnable to read response, assuming y.\n");
 323         exit(1);
 324     }
 325 }
 326
 327 static void
 328 help_cmd(char **ptr)
 329 {
 330     struct cmd *cmd;
 331
 332     for (cmd = supported_cmds; cmd->cmd != NULL; cmd++)
 333         if (cmd->help != NULL)
 334             printf("%s\t%s\n", cmd->cmd, cmd->help);
 335 }
 336
 337 static int done;
 338
 339 static void
 340 exit_cmd(char **ptr)
 341 {
 342     done = 1;
 343 }
 344
 345 static void
 346 purify_cmd(char **ptr)
 347 {
 348     purify(NIL, NIL);
 349 }
 350
 351 static void
 352 print_context(os_context_t *context)
 353 {
 354     int i;
 355
 356     for (i = 0; i < NREGS; i++) {
 357         printf("%s:\t", lisp_register_names[i]);
 358 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 359         brief_print((lispobj)(*os_context_register_addr(context, i*2)));
 360 #else
 361         brief_print((lispobj)(*os_context_register_addr(context,i)));
 362 #endif
 363     }
 364 #ifdef LISP_FEATURE_DARWIN
 365     printf("DAR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 41)));
 366     printf("DSISR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 42)));
 367 #endif
 368     printf("PC:\t\t  0x%08lx\n",
 369            (unsigned long)(*os_context_pc_addr(context)));
 370 }
 371
 372 static void
 373 print_context_cmd(char **ptr)
 374 {
 375     int free_ici;
 376     struct thread *thread=arch_os_get_current_thread();
 377
 378     free_ici = fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread));
 379
 380     if (more_p(ptr)) {
 381         int index;
 382
 383         index = parse_number(ptr);
 384
 385         if ((index >= 0) && (index < free_ici)) {
 386             printf("There are %d interrupt contexts.\n", free_ici);
 387             printf("printing context %d\n", index);
 388             print_context(thread->interrupt_contexts[index]);
 389         } else {
 390             printf("There aren't that many/few contexts.\n");
 391             printf("There are %d interrupt contexts.\n", free_ici);
 392         }
 393     } else {
 394         if (free_ici == 0)
 395             printf("There are no interrupt contexts!\n");
 396         else {
 397             printf("There are %d interrupt contexts.\n", free_ici);
 398             printf("printing context %d\n", free_ici - 1);
 399             print_context(thread->interrupt_contexts[free_ici - 1]);
 400         }
 401     }
 402 }
 403
 404 static void
 405 backtrace_cmd(char **ptr)
 406 {
 407     void lisp_backtrace(int frames);
 408     int n;
 409
 410     if (more_p(ptr))
 411         n = parse_number(ptr);
 412     else
 413         n = 100;
 414
 415     printf("Backtrace:\n");
 416     lisp_backtrace(n);
 417 }
 418
 419 static void
 420 catchers_cmd(char **ptr)
 421 {
 422     struct catch_block *catch;
 423     struct thread *thread=arch_os_get_current_thread();
 424
 425     catch = (struct catch_block *)SymbolValue(CURRENT_CATCH_BLOCK,thread);
 426
 427     if (catch == NULL)
 428         printf("There are no active catchers!\n");
 429     else {
 430         while (catch != NULL) {
 431             printf("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\t"
 432                    "code: 0x%08lX\n\tentry: 0x%08lX\n\ttag: ",
 433                    (long unsigned)catch,
 434                    (long unsigned)(catch->uwp),
 435                    (long unsigned)(catch->cfp),
 436 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 437                    (long unsigned)component_ptr_from_pc((void*)catch->entry_pc)
 438                        + OTHER_POINTER_LOWTAG,
 439 #else
 440                    (long unsigned)(catch->code),
 441 #endif
 442                    (long unsigned)(catch->entry_pc));
 443             brief_print((lispobj)catch->tag);
 444             catch = catch->previous_catch;
 445         }
 446     }
 447 }
 448
 449 static void
 450 grab_sigs_cmd(char **ptr)
 451 {
 452     extern void sigint_init(void);
 453
 454     printf("Grabbing signals.\n");
 455     sigint_init();
 456 }
 457
 458 static void
 459 sub_monitor(void)
 460 {
 461     struct cmd *cmd, *found;
 462     char buf[256];
 463     char *line, *ptr, *token;
 464     int ambig;
 465
 466     if (!ldb_in) {
 467 #ifndef LISP_FEATURE_WIN32
 468         ldb_in = fopen("/dev/tty","r+");
 469         if (ldb_in == NULL) {
 470             perror("Error opening /dev/tty");
 471             ldb_in = stdin;
 472         }
 473 #else
 474         ldb_in = stdin;
 475 #endif
 476         ldb_in_fd = fileno(ldb_in);
 477     }
 478
 479     while (!done) {
 480         printf("ldb> ");
 481         fflush(stdout);
 482         line = fgets(buf, sizeof(buf), ldb_in);
 483         if (line == NULL) {
 484             exit(1);
 485         }
 486         ptr = line;
 487         if ((token = parse_token(&ptr)) == NULL)
 488             continue;
 489         ambig = 0;
 490         found = NULL;
 491         for (cmd = supported_cmds; cmd->cmd != NULL; cmd++) {
 492             if (strcmp(token, cmd->cmd) == 0) {
 493                 found = cmd;
 494                 ambig = 0;
 495                 break;
 496             }
 497             else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
 498                 if (found)
 499                     ambig = 1;
 500                 else
 501                     found = cmd;
 502             }
 503         }
 504         if (ambig)
 505             printf("``%s'' is ambiguous.\n", token);
 506         else if (found == NULL)
 507             printf("unknown command: ``%s''\n", token);
 508         else {
 509             reset_printer();
 510             (*found->fn)(&ptr);
 511         }
 512     }
 513 }
 514
 515 void
 516 ldb_monitor()
 517 {
 518     jmp_buf oldbuf;
 519
 520     bcopy(curbuf, oldbuf, sizeof(oldbuf));
 521
 522     printf("Welcome to LDB, a low-level debugger for the Lisp runtime environment.\n");
 523
 524     setjmp(curbuf);
 525
 526     sub_monitor();
 527
 528     done = 0;
 529
 530     bcopy(oldbuf, curbuf, sizeof(curbuf));
 531 }
 532
 533 void
 534 throw_to_monitor()
 535 {
 536     longjmp(curbuf, 1);
 537 }
 538
 539 #endif /* defined(LISP_FEATURE_SB_LDB) */
 540
 541 /* what we do when things go badly wrong at a low level */
 542 void
 543 monitor_or_something()
 544 {
 545 #if defined(LISP_FEATURE_SB_LDB)
 546     ldb_monitor();
 547 #else
 548      fprintf(stderr,
 549 "The system is too badly corrupted or confused to continue at the Lisp\n\
 550 level. If the system had been compiled with the SB-LDB feature, we'd drop\n\
 551 into the LDB low-level debugger now. But there's no LDB in this build, so\n\
 552 we can't really do anything but just exit, sorry.\n");
 553     exit(1);
 554 #endif
 555 }