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     printf("CSP\t=\t0x%08lx\n", (unsigned long)current_control_stack_pointer);
 192     printf("CFP\t=\t0x%08lx\n", (unsigned long)current_control_frame_pointer);
 193
 194 #ifdef reg_BSP
 195     printf("BSP\t=\t0x%08lx\n", (unsigned long)current_binding_stack_pointer);
 196 #else
 197     /* printf("BSP\t=\t0x%08lx\n",
 198            (unsigned long)SymbolValue(BINDING_STACK_POINTER)); */
 199 #endif
 200
 201 #ifdef LISP_FEATURE_GENCGC
 202     /* printf("DYNAMIC\t=\t0x%08lx\n", DYNAMIC_SPACE_START); */
 203 #else
 204     printf("DYNAMIC\t=\t0x%08lx\n", (unsigned long)current_dynamic_space);
 205 #endif
 206
 207 #ifdef reg_ALLOC
 208     printf("ALLOC\t=\t0x%08lx\n", (unsigned long)dynamic_space_free_pointer);
 209 #else
 210     printf("ALLOC\t=\t0x%08lx\n",
 211            (unsigned long)SymbolValue(ALLOCATION_POINTER,
 212                                       arch_os_get_current_thread()));
 213 #endif
 214
 215 #ifndef LISP_FEATURE_GENCGC
 216     printf("TRIGGER\t=\t0x%08lx\n", (unsigned long)current_auto_gc_trigger);
 217 #endif
 218
 219 #if 0
 220     printf("STATIC\t=\t0x%08lx\n",
 221            (unsigned long)SymbolValue(STATIC_SPACE_FREE_POINTER));
 222     printf("RDONLY\t=\t0x%08lx\n",
 223            (unsigned long)SymbolValue(READ_ONLY_SPACE_FREE_POINTER));
 224 #endif
 225 }
 226
 227 static void
 228 search_cmd(char **ptr)
 229 {
 230     static int lastval = 0, lastcount = 0;
 231     static lispobj *start = 0, *end = 0;
 232     int val, count;
 233     lispobj *addr, obj;
 234
 235     if (more_p(ptr)) {
 236         val = parse_number(ptr);
 237         if (val < 0 || val > 0xff) {
 238             printf("can only search for single bytes\n");
 239             return;
 240         }
 241         if (more_p(ptr)) {
 242             addr = (lispobj *)native_pointer((long)parse_addr(ptr));
 243             if (more_p(ptr)) {
 244                 count = parse_number(ptr);
 245             }
 246             else {
 247                 /* Specified value and address, but no count. Only one. */
 248                 count = -1;
 249             }
 250         }
 251         else {
 252             /* Specified a value, but no address, so search same range. */
 253             addr = start;
 254             count = lastcount;
 255         }
 256     }
 257     else {
 258         /* Specified nothing, search again for val. */
 259         val = lastval;
 260         addr = end;
 261         count = lastcount;
 262     }
 263
 264     lastval = val;
 265     start = end = addr;
 266     lastcount = count;
 267
 268     printf("searching for 0x%x at 0x%08lX\n", val, (unsigned long)end);
 269
 270     while (search_for_type(val, &end, &count)) {
 271         printf("found 0x%x at 0x%08lX:\n", val, (unsigned long)end);
 272         obj = *end;
 273         addr = end;
 274         end += 2;
 275         if (widetag_of(obj) == SIMPLE_FUN_HEADER_WIDETAG) {
 276             print((long)addr | FUN_POINTER_LOWTAG);
 277         } else if (lowtag_of(obj) == OTHER_IMMEDIATE_0_LOWTAG ||
 278                    lowtag_of(obj) == OTHER_IMMEDIATE_1_LOWTAG) {
 279             print((lispobj)addr | OTHER_POINTER_LOWTAG);
 280         } else {
 281             print((lispobj)addr);
 282         } if (count == -1) {
 283             return;
 284         }
 285     }
 286 }
 287
 288 /* (There used to be call_cmd() here, to call known-at-cold-init-time
 289  * Lisp functions from ldb, but it bitrotted and was deleted in
 290  * sbcl-0.7.5.1. See older CVS versions if you want to resuscitate
 291  * it.) */
 292
 293 static void
 294 flush_cmd(char **ptr)
 295 {
 296     flush_vars();
 297 }
 298
 299 static void
 300 quit_cmd(char **ptr)
 301 {
 302     char buf[10];
 303
 304     printf("Really quit? [y] ");
 305     fflush(stdout);
 306     fgets(buf, sizeof(buf), ldb_in);
 307     if (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')
 308         exit(1);
 309 }
 310
 311 static void
 312 help_cmd(char **ptr)
 313 {
 314     struct cmd *cmd;
 315
 316     for (cmd = supported_cmds; cmd->cmd != NULL; cmd++)
 317         if (cmd->help != NULL)
 318             printf("%s\t%s\n", cmd->cmd, cmd->help);
 319 }
 320
 321 static int done;
 322
 323 static void
 324 exit_cmd(char **ptr)
 325 {
 326     done = 1;
 327 }
 328
 329 static void
 330 purify_cmd(char **ptr)
 331 {
 332     purify(NIL, NIL);
 333 }
 334
 335 static void
 336 print_context(os_context_t *context)
 337 {
 338     int i;
 339
 340     for (i = 0; i < NREGS; i++) {
 341         printf("%s:\t", lisp_register_names[i]);
 342 #ifdef LISP_FEATURE_X86
 343         brief_print((lispobj)(*os_context_register_addr(context,
 344                                                         i*2)));
 345 #else
 346         brief_print((lispobj)(*os_context_register_addr(context,i)));
 347 #endif
 348     }
 349 #ifdef LISP_FEATURE_DARWIN
 350     printf("DAR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 41)));
 351     printf("DSISR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 42)));
 352 #endif
 353     printf("PC:\t\t  0x%08lx\n",
 354            (unsigned long)(*os_context_pc_addr(context)));
 355 }
 356
 357 static void
 358 print_context_cmd(char **ptr)
 359 {
 360     int free_ici;
 361     struct thread *thread=arch_os_get_current_thread();
 362
 363     free_ici = fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread));
 364
 365     if (more_p(ptr)) {
 366         int index;
 367
 368         index = parse_number(ptr);
 369
 370         if ((index >= 0) && (index < free_ici)) {
 371             printf("There are %d interrupt contexts.\n", free_ici);
 372             printf("printing context %d\n", index);
 373             print_context(thread->interrupt_contexts[index]);
 374         } else {
 375             printf("There aren't that many/few contexts.\n");
 376             printf("There are %d interrupt contexts.\n", free_ici);
 377         }
 378     } else {
 379         if (free_ici == 0)
 380             printf("There are no interrupt contexts!\n");
 381         else {
 382             printf("There are %d interrupt contexts.\n", free_ici);
 383             printf("printing context %d\n", free_ici - 1);
 384             print_context(thread->interrupt_contexts[free_ici - 1]);
 385         }
 386     }
 387 }
 388
 389 static void
 390 backtrace_cmd(char **ptr)
 391 {
 392     void backtrace(int frames);
 393     int n;
 394
 395     if (more_p(ptr))
 396         n = parse_number(ptr);
 397     else
 398         n = 100;
 399
 400     printf("Backtrace:\n");
 401     backtrace(n);
 402 }
 403
 404 static void
 405 catchers_cmd(char **ptr)
 406 {
 407     struct catch_block *catch;
 408     struct thread *thread=arch_os_get_current_thread();
 409
 410     catch = (struct catch_block *)SymbolValue(CURRENT_CATCH_BLOCK,thread);
 411
 412     if (catch == NULL)
 413         printf("There are no active catchers!\n");
 414     else {
 415         while (catch != NULL) {
 416             printf("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\t"
 417                    "code: 0x%08lX\n\tentry: 0x%08lX\n\ttag: ",
 418                    (unsigned long)catch,
 419                    (unsigned long)(catch->current_uwp),
 420                    (unsigned long)(catch->current_cont),
 421 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 422                    (unsigned long)component_ptr_from_pc((void*)catch->entry_pc)
 423                        + OTHER_POINTER_LOWTAG,
 424 #else
 425                    (unsigned long)(catch->current_code),
 426 #endif
 427                    (unsigned long)(catch->entry_pc));
 428             brief_print((lispobj)catch->tag);
 429             catch = catch->previous_catch;
 430         }
 431     }
 432 }
 433
 434 static void
 435 grab_sigs_cmd(char **ptr)
 436 {
 437     extern void sigint_init(void);
 438
 439     printf("Grabbing signals.\n");
 440     sigint_init();
 441 }
 442
 443 static void
 444 sub_monitor(void)
 445 {
 446     struct cmd *cmd, *found;
 447     char buf[256];
 448     char *line, *ptr, *token;
 449     int ambig;
 450
 451     if (!ldb_in) {
 452 #ifndef LISP_FEATURE_WIN32
 453         ldb_in = fopen("/dev/tty","r+");
 454 #else
 455         ldb_in = stdin;
 456 #endif
 457         ldb_in_fd = fileno(ldb_in);
 458     }
 459
 460     while (!done) {
 461         printf("ldb> ");
 462         fflush(stdout);
 463         line = fgets(buf, sizeof(buf), ldb_in);
 464         if (line == NULL) {
 465             exit(1);
 466         }
 467         ptr = line;
 468         if ((token = parse_token(&ptr)) == NULL)
 469             continue;
 470         ambig = 0;
 471         found = NULL;
 472         for (cmd = supported_cmds; cmd->cmd != NULL; cmd++) {
 473             if (strcmp(token, cmd->cmd) == 0) {
 474                 found = cmd;
 475                 ambig = 0;
 476                 break;
 477             }
 478             else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
 479                 if (found)
 480                     ambig = 1;
 481                 else
 482                     found = cmd;
 483             }
 484         }
 485         if (ambig)
 486             printf("``%s'' is ambiguous.\n", token);
 487         else if (found == NULL)
 488             printf("unknown command: ``%s''\n", token);
 489         else {
 490             reset_printer();
 491             (*found->fn)(&ptr);
 492         }
 493     }
 494 }
 495
 496 void
 497 ldb_monitor()
 498 {
 499     jmp_buf oldbuf;
 500
 501     bcopy(curbuf, oldbuf, sizeof(oldbuf));
 502
 503     printf("Welcome to LDB, a low-level debugger for the Lisp runtime environment.\n");
 504
 505     setjmp(curbuf);
 506
 507     sub_monitor();
 508
 509     done = 0;
 510
 511     bcopy(oldbuf, curbuf, sizeof(curbuf));
 512 }
 513
 514 void
 515 throw_to_monitor()
 516 {
 517     longjmp(curbuf, 1);
 518 }
 519
 520 #endif /* defined(LISP_FEATURE_SB_LDB) */
 521
 522 /* what we do when things go badly wrong at a low level */
 523 void
 524 monitor_or_something()
 525 {
 526 #if defined(LISP_FEATURE_SB_LDB)
 527     ldb_monitor();
 528 #else
 529      fprintf(stderr,
 530 "The system is too badly corrupted or confused to continue at the Lisp\n\
 531 level. If the system had been compiled with the SB-LDB feature, we'd drop\n\
 532 into the LDB low-level debugger now. But there's no LDB in this build, so\n\
 533 we can't really do anything but just exit, sorry.\n");
 534     exit(1);
 535 #endif
 536 }