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 = N_WORD_BYTES;
 134     else {
 135         displacement = -N_WORD_BYTES;
 136         count = -count;
 137     }
 138
 139     while (count-- > 0) {
 140 #ifndef LISP_FEATURE_ALPHA
 141         printf("0x%p: ", (os_vm_address_t) 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 char *cptr = (unsigned char *)addr;
 152
 153 #if N_WORD_BYTES == 8
 154             printf("0x%016lx | %c%c%c%c%c%c%c%c\n",
 155                    lptr[0],
 156                    visible(cptr[0]), visible(cptr[1]),
 157                    visible(cptr[2]), visible(cptr[3]),
 158                    visible(cptr[4]), visible(cptr[5]),
 159                    visible(cptr[6]), visible(cptr[7]));
 160 #else
 161             unsigned short *sptr = (unsigned short *)addr;
 162             printf("0x%08lx   0x%04x 0x%04x   "
 163                    "0x%02x 0x%02x 0x%02x 0x%02x    "
 164                    "%c%c"
 165                    "%c%c\n",
 166                    lptr[0], sptr[0], sptr[1],
 167                    cptr[0], cptr[1], cptr[2], cptr[3],
 168                    visible(cptr[0]), visible(cptr[1]),
 169                    visible(cptr[2]), visible(cptr[3]));
 170 #endif
 171         }
 172         else
 173             printf("invalid Lisp-level address\n");
 174
 175         addr += displacement;
 176     }
 177
 178     lastaddr = addr;
 179 }
 180
 181 static void
 182 print_cmd(char **ptr)
 183 {
 184     lispobj obj = parse_lispobj(ptr);
 185
 186     print(obj);
 187 }
 188
 189 static void
 190 kill_cmd(char **ptr)
 191 {
 192 #ifndef LISP_FEATURE_WIN32
 193     kill(getpid(), parse_number(ptr));
 194 #endif
 195 }
 196
 197 static void
 198 regs_cmd(char **ptr)
 199 {
 200     struct thread *thread=arch_os_get_current_thread();
 201
 202     printf("CSP\t=\t0x%p   ", access_control_stack_pointer(thread));
 203 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
 204     printf("CFP\t=\t0x%p   ", access_control_frame_pointer(thread));
 205 #endif
 206
 207 #ifdef reg_BSP
 208     printf("BSP\t=\t0x%p\n", get_binding_stack_pointer(thread));
 209 #else
 210     /* printf("BSP\t=\t0x%08lx\n",
 211            (unsigned long)SymbolValue(BINDING_STACK_POINTER)); */
 212     printf("\n");
 213 #endif
 214
 215 #ifdef LISP_FEATURE_GENCGC
 216     /* printf("DYNAMIC\t=\t0x%08lx\n", DYNAMIC_SPACE_START); */
 217 #else
 218     printf("STATIC\t=\t0x%p   ",
 219            SymbolValue(STATIC_SPACE_FREE_POINTER, thread));
 220     printf("RDONLY\t=\t0x%08lx   ",
 221            (unsigned long)SymbolValue(READ_ONLY_SPACE_FREE_POINTER, thread));
 222     printf("DYNAMIC\t=\t0x%08lx\n", (unsigned long)current_dynamic_space);
 223 #endif
 224
 225 #ifdef reg_ALLOC
 226     printf("ALLOC\t=\t0x%08lx\n", (unsigned long)dynamic_space_free_pointer);
 227 #else
 228     printf("ALLOC\t=\t0x%08lx\n",
 229            (unsigned long)SymbolValue(ALLOCATION_POINTER, thread));
 230 #endif
 231
 232 #ifndef LISP_FEATURE_GENCGC
 233     printf("TRIGGER\t=\t0x%08lx\n", (unsigned long)current_auto_gc_trigger);
 234 #endif
 235 }
 236
 237 static void
 238 search_cmd(char **ptr)
 239 {
 240     static int lastval = 0, lastcount = 0;
 241     static lispobj *start = 0, *end = 0;
 242     int val, count;
 243     lispobj *addr, obj;
 244
 245     if (more_p(ptr)) {
 246         val = parse_number(ptr);
 247         if (val < 0 || val > 0xff) {
 248             printf("can only search for single bytes\n");
 249             return;
 250         }
 251         if (more_p(ptr)) {
 252             addr = (lispobj *)native_pointer((uword_t)parse_addr(ptr));
 253             if (more_p(ptr)) {
 254                 count = parse_number(ptr);
 255             }
 256             else {
 257                 /* Specified value and address, but no count. Only one. */
 258                 count = -1;
 259             }
 260         }
 261         else {
 262             /* Specified a value, but no address, so search same range. */
 263             addr = start;
 264             count = lastcount;
 265         }
 266     }
 267     else {
 268         /* Specified nothing, search again for val. */
 269         val = lastval;
 270         addr = end;
 271         count = lastcount;
 272     }
 273
 274     lastval = val;
 275     start = end = addr;
 276     lastcount = count;
 277
 278     printf("searching for 0x%x at 0x%p\n", val, (void*)(uword_t)end);
 279
 280     while (search_for_type(val, &end, &count)) {
 281         printf("found 0x%x at 0x%p:\n", val, (void*)(uword_t)end);
 282         obj = *end;
 283         addr = end;
 284         end += 2;
 285         if (widetag_of(obj) == SIMPLE_FUN_HEADER_WIDETAG) {
 286             print((uword_t)addr | FUN_POINTER_LOWTAG);
 287         } else if (other_immediate_lowtag_p(obj)) {
 288             print((lispobj)addr | OTHER_POINTER_LOWTAG);
 289         } else {
 290             print((lispobj)addr);
 291         } if (count == -1) {
 292             return;
 293         }
 294     }
 295 }
 296
 297 /* (There used to be call_cmd() here, to call known-at-cold-init-time
 298  * Lisp functions from ldb, but it bitrotted and was deleted in
 299  * sbcl-0.7.5.1. See older CVS versions if you want to resuscitate
 300  * it.) */
 301
 302 static void
 303 flush_cmd(char **ptr)
 304 {
 305     flush_vars();
 306 }
 307
 308 static void
 309 quit_cmd(char **ptr)
 310 {
 311     char buf[10];
 312
 313     printf("Really quit? [y] ");
 314     fflush(stdout);
 315     if (fgets(buf, sizeof(buf), ldb_in)) {
 316         if (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')
 317             exit(1);
 318     } else {
 319         printf("\nUnable to read response, assuming y.\n");
 320         exit(1);
 321     }
 322 }
 323
 324 static void
 325 help_cmd(char **ptr)
 326 {
 327     struct cmd *cmd;
 328
 329     for (cmd = supported_cmds; cmd->cmd != NULL; cmd++)
 330         if (cmd->help != NULL)
 331             printf("%s\t%s\n", cmd->cmd, cmd->help);
 332 }
 333
 334 static int done;
 335
 336 static void
 337 exit_cmd(char **ptr)
 338 {
 339     done = 1;
 340 }
 341
 342 static void
 343 purify_cmd(char **ptr)
 344 {
 345     purify(NIL, NIL);
 346 }
 347
 348 static void
 349 print_context(os_context_t *context)
 350 {
 351     int i;
 352
 353     for (i = 0; i < NREGS; i++) {
 354         printf("%s:\t", lisp_register_names[i]);
 355 #ifdef LISP_FEATURE_X86
 356         brief_print((lispobj)(*os_context_register_addr(context,
 357                                                         i*2)));
 358 #else
 359         brief_print((lispobj)(*os_context_register_addr(context,i)));
 360 #endif
 361     }
 362 #ifdef LISP_FEATURE_DARWIN
 363     printf("DAR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 41)));
 364     printf("DSISR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 42)));
 365 #endif
 366     printf("PC:\t\t  0x%08lx\n",
 367            (unsigned long)(*os_context_pc_addr(context)));
 368 }
 369
 370 static void
 371 print_context_cmd(char **ptr)
 372 {
 373     int free_ici;
 374     struct thread *thread=arch_os_get_current_thread();
 375
 376     free_ici = fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread));
 377
 378     if (more_p(ptr)) {
 379         int index;
 380
 381         index = parse_number(ptr);
 382
 383         if ((index >= 0) && (index < free_ici)) {
 384             printf("There are %d interrupt contexts.\n", free_ici);
 385             printf("printing context %d\n", index);
 386             print_context(thread->interrupt_contexts[index]);
 387         } else {
 388             printf("There aren't that many/few contexts.\n");
 389             printf("There are %d interrupt contexts.\n", free_ici);
 390         }
 391     } else {
 392         if (free_ici == 0)
 393             printf("There are no interrupt contexts!\n");
 394         else {
 395             printf("There are %d interrupt contexts.\n", free_ici);
 396             printf("printing context %d\n", free_ici - 1);
 397             print_context(thread->interrupt_contexts[free_ici - 1]);
 398         }
 399     }
 400 }
 401
 402 static void
 403 backtrace_cmd(char **ptr)
 404 {
 405     void lisp_backtrace(int frames);
 406     int n;
 407
 408     if (more_p(ptr))
 409         n = parse_number(ptr);
 410     else
 411         n = 100;
 412
 413     printf("Backtrace:\n");
 414     lisp_backtrace(n);
 415 }
 416
 417 static void
 418 catchers_cmd(char **ptr)
 419 {
 420     struct catch_block *catch;
 421     struct thread *thread=arch_os_get_current_thread();
 422
 423     catch = (struct catch_block *)SymbolValue(CURRENT_CATCH_BLOCK,thread);
 424
 425     if (catch == NULL)
 426         printf("There are no active catchers!\n");
 427     else {
 428         while (catch != NULL) {
 429             printf("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\t"
 430                    "code: 0x%08lX\n\tentry: 0x%08lX\n\ttag: ",
 431                    (uword_t)catch,
 432                    (uword_t)(catch->current_uwp),
 433                    (uword_t)(catch->current_cont),
 434 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 435                    (uword_t)component_ptr_from_pc((void*)catch->entry_pc)
 436                        + OTHER_POINTER_LOWTAG,
 437 #else
 438                    (uword_t)(catch->current_code),
 439 #endif
 440                    (uword_t)(catch->entry_pc));
 441             brief_print((lispobj)catch->tag);
 442             catch = catch->previous_catch;
 443         }
 444     }
 445 }
 446
 447 static void
 448 grab_sigs_cmd(char **ptr)
 449 {
 450     extern void sigint_init(void);
 451
 452     printf("Grabbing signals.\n");
 453     sigint_init();
 454 }
 455
 456 static void
 457 sub_monitor(void)
 458 {
 459     struct cmd *cmd, *found;
 460     char buf[256];
 461     char *line, *ptr, *token;
 462     int ambig;
 463
 464     if (!ldb_in) {
 465 #ifndef LISP_FEATURE_WIN32
 466         ldb_in = fopen("/dev/tty","r+");
 467         if (ldb_in == NULL) {
 468             perror("Error opening /dev/tty");
 469             ldb_in = stdin;
 470         }
 471 #else
 472         ldb_in = stdin;
 473 #endif
 474         ldb_in_fd = fileno(ldb_in);
 475     }
 476
 477     while (!done) {
 478         printf("ldb> ");
 479         fflush(stdout);
 480         line = fgets(buf, sizeof(buf), ldb_in);
 481         if (line == NULL) {
 482             exit(1);
 483         }
 484         ptr = line;
 485         if ((token = parse_token(&ptr)) == NULL)
 486             continue;
 487         ambig = 0;
 488         found = NULL;
 489         for (cmd = supported_cmds; cmd->cmd != NULL; cmd++) {
 490             if (strcmp(token, cmd->cmd) == 0) {
 491                 found = cmd;
 492                 ambig = 0;
 493                 break;
 494             }
 495             else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
 496                 if (found)
 497                     ambig = 1;
 498                 else
 499                     found = cmd;
 500             }
 501         }
 502         if (ambig)
 503             printf("``%s'' is ambiguous.\n", token);
 504         else if (found == NULL)
 505             printf("unknown command: ``%s''\n", token);
 506         else {
 507             reset_printer();
 508             (*found->fn)(&ptr);
 509         }
 510     }
 511 }
 512
 513 void
 514 ldb_monitor()
 515 {
 516     jmp_buf oldbuf;
 517
 518     bcopy(curbuf, oldbuf, sizeof(oldbuf));
 519
 520     printf("Welcome to LDB, a low-level debugger for the Lisp runtime environment.\n");
 521
 522     setjmp(curbuf);
 523
 524     sub_monitor();
 525
 526     done = 0;
 527
 528     bcopy(oldbuf, curbuf, sizeof(curbuf));
 529 }
 530
 531 void
 532 throw_to_monitor()
 533 {
 534     longjmp(curbuf, 1);
 535 }
 536
 537 #endif /* defined(LISP_FEATURE_SB_LDB) */
 538
 539 /* what we do when things go badly wrong at a low level */
 540 void
 541 monitor_or_something()
 542 {
 543 #if defined(LISP_FEATURE_SB_LDB)
 544     ldb_monitor();
 545 #else
 546      fprintf(stderr,
 547 "The system is too badly corrupted or confused to continue at the Lisp\n\
 548 level. If the system had been compiled with the SB-LDB feature, we'd drop\n\
 549 into the LDB low-level debugger now. But there's no LDB in this build, so\n\
 550 we can't really do anything but just exit, sorry.\n");
 551     exit(1);
 552 #endif
 553 }