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 #include "print.h"
  30 #include "arch.h"
  31 #include "interr.h"
  32 #include "search.h"
  33 #include "purify.h"
  34 #include "globals.h"
  35 #include "lispregs.h"
  36 #include "interrupt.h"
  37 #include "thread.h"
  38 #include "genesis/static-symbols.h"
  39 #include "genesis/primitive-objects.h"
  40
  41
  42
  43 /* When we need to do command input, we use this stream, which is not
  44  * in general stdin, so that things will "work" (as well as being
  45  * thrown into ldb can be considered "working":-) even in a process
  46  * where standard input has been redirected to a file or pipe.
  47  *
  48  * (We could set up output to go to a special ldb_out stream for the
  49  * same reason, but there's been no pressure for that so far.)
  50  *
  51  * The enter-the-ldb-monitor function is responsible for setting up
  52  * this stream. */
  53 static FILE *ldb_in = 0;
  54 static int ldb_in_fd = -1;
  55
  56 typedef void cmd(char **ptr);
  57
  58 static cmd dump_cmd, print_cmd, quit_cmd, help_cmd;
  59 static cmd flush_cmd, search_cmd, regs_cmd, exit_cmd;
  60 static cmd print_context_cmd;
  61 static cmd backtrace_cmd, purify_cmd, catchers_cmd;
  62 static cmd grab_sigs_cmd;
  63 static cmd kill_cmd;
  64
  65 static struct cmd {
  66     char *cmd, *help;
  67     void (*fn)(char **ptr);
  68 } supported_cmds[] = {
  69     {"help", "Display this help information.", help_cmd},
  70     {"?", "(an alias for help)", help_cmd},
  71     {"backtrace", "Backtrace up to N frames.", backtrace_cmd},
  72     {"catchers", "Print a list of all the active catchers.", catchers_cmd},
  73     {"context", "Print interrupt context number I.", print_context_cmd},
  74     {"dump", "Dump memory starting at ADDRESS for COUNT words.", dump_cmd},
  75     {"d", "(an alias for dump)", dump_cmd},
  76     {"exit", "Exit this instance of the monitor.", exit_cmd},
  77     {"flush", "Flush all temp variables.", flush_cmd},
  78     /* (Classic CMU CL had a "gc" command here, which seems like a
  79      * reasonable idea, but the code was stale (incompatible with
  80      * gencgc) so I just flushed it. -- WHN 20000814 */
  81     {"grab-signals", "Set the signal handlers to call LDB.", grab_sigs_cmd},
  82     {"kill", "Kill ourself with signal number N (useful if running under gdb)",
  83      kill_cmd},
  84     {"purify", "Purify. (Caveat purifier!)", purify_cmd},
  85     {"print", "Print object at ADDRESS.", print_cmd},
  86     {"p", "(an alias for print)", print_cmd},
  87     {"quit", "Quit.", quit_cmd},
  88     {"regs", "Display current Lisp registers.", regs_cmd},
  89     {"search", "Search for TYPE starting at ADDRESS for a max of COUNT words.", search_cmd},
  90     {"s", "(an alias for search)", search_cmd},
  91     {NULL, NULL, NULL}
  92 };
  93
  94 static jmp_buf curbuf;
  95
  96 static int
  97 visible(unsigned char c)
  98 {
  99     if (c < ' ' || c > '~')
 100         return ' ';
 101     else
 102         return c;
 103 }
 104
 105 static void
 106 dump_cmd(char **ptr)
 107 {
 108     static char *lastaddr = 0;
 109     static int lastcount = 20;
 110
 111     char *addr = lastaddr;
 112     int count = lastcount, displacement;
 113     int force = 0;
 114
 115     if (more_p(ptr)) {
 116         if (!strncmp(*ptr, "-f ", 3)) {
 117           force = 1;
 118           *ptr += 3;
 119         }
 120         addr = parse_addr(ptr, !force);
 121
 122         if (more_p(ptr))
 123             count = parse_number(ptr);
 124     }
 125
 126     if (count == 0) {
 127         printf("COUNT must be non-zero.\n");
 128         return;
 129     }
 130
 131     lastcount = count;
 132
 133     if (count > 0)
 134         displacement = N_WORD_BYTES;
 135     else {
 136         displacement = -N_WORD_BYTES;
 137         count = -count;
 138     }
 139
 140     while (count-- > 0) {
 141 #ifndef LISP_FEATURE_ALPHA
 142         printf("%p: ", (os_vm_address_t) addr);
 143 #else
 144         printf("0x%08X: ", (u32) addr);
 145 #endif
 146         if (force || gc_managed_addr_p((lispobj)addr)) {
 147 #ifndef LISP_FEATURE_ALPHA
 148             unsigned long *lptr = (unsigned long *)addr;
 149 #else
 150             u32 *lptr = (u32 *)addr;
 151 #endif
 152             unsigned char *cptr = (unsigned char *)addr;
 153
 154 #if N_WORD_BYTES == 8
 155             printf("0x%016lx | %c%c%c%c%c%c%c%c\n",
 156                    lptr[0],
 157                    visible(cptr[0]), visible(cptr[1]),
 158                    visible(cptr[2]), visible(cptr[3]),
 159                    visible(cptr[4]), visible(cptr[5]),
 160                    visible(cptr[6]), visible(cptr[7]));
 161 #else
 162             unsigned short *sptr = (unsigned short *)addr;
 163             printf("0x%08lx   0x%04x 0x%04x   "
 164                    "0x%02x 0x%02x 0x%02x 0x%02x    "
 165                    "%c%c"
 166                    "%c%c\n",
 167                    lptr[0], sptr[0], sptr[1],
 168                    cptr[0], cptr[1], cptr[2], cptr[3],
 169                    visible(cptr[0]), visible(cptr[1]),
 170                    visible(cptr[2]), visible(cptr[3]));
 171 #endif
 172         }
 173         else
 174             printf("invalid Lisp-level address\n");
 175
 176         addr += displacement;
 177     }
 178
 179     lastaddr = addr;
 180 }
 181
 182 static void
 183 print_cmd(char **ptr)
 184 {
 185     lispobj obj = parse_lispobj(ptr);
 186
 187     print(obj);
 188 }
 189
 190 static void
 191 kill_cmd(char **ptr)
 192 {
 193 #ifndef LISP_FEATURE_WIN32
 194     kill(getpid(), parse_number(ptr));
 195 #endif
 196 }
 197
 198 static void
 199 regs_cmd(char **ptr)
 200 {
 201     struct thread __attribute__((unused)) *thread=arch_os_get_current_thread();
 202
 203     printf("CSP\t=\t%p   ", access_control_stack_pointer(thread));
 204 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
 205     printf("CFP\t=\t%p   ", access_control_frame_pointer(thread));
 206 #endif
 207
 208 #ifdef reg_BSP
 209     printf("BSP\t=\t%p\n", get_binding_stack_pointer(thread));
 210 #else
 211     /* printf("BSP\t=\t%p\n", (void*)SymbolValue(BINDING_STACK_POINTER)); */
 212     printf("\n");
 213 #endif
 214
 215 #ifdef LISP_FEATURE_GENCGC
 216     /* printf("DYNAMIC\t=\t%p\n", (void*)DYNAMIC_SPACE_START); */
 217 #else
 218     printf("STATIC\t=\t%p   ", static_space_free_pointer);
 219     printf("RDONLY\t=\t%p   ", read_only_space_free_pointer);
 220     printf("DYNAMIC\t=\t%p\n", (void*)current_dynamic_space);
 221 #endif
 222
 223 #ifndef ALLOCATION_POINTER
 224     printf("ALLOC\t=\t%p\n", (void*)dynamic_space_free_pointer);
 225 #else
 226     printf("ALLOC\t=\t%p\n", (void*)SymbolValue(ALLOCATION_POINTER, thread));
 227 #endif
 228
 229 #ifndef LISP_FEATURE_GENCGC
 230     printf("TRIGGER\t=\t%p\n", (void*)current_auto_gc_trigger);
 231 #endif
 232 }
 233
 234 static void
 235 search_cmd(char **ptr)
 236 {
 237     static int lastval = 0, lastcount = 0;
 238     static lispobj *start = 0, *end = 0;
 239     int val, count;
 240     lispobj *addr, obj;
 241
 242     if (more_p(ptr)) {
 243         val = parse_number(ptr);
 244         if (val < 0 || val > 0xff) {
 245             printf("can only search for single bytes\n");
 246             return;
 247         }
 248         if (more_p(ptr)) {
 249             addr = native_pointer((uword_t)parse_addr(ptr, 1));
 250             if (more_p(ptr)) {
 251                 count = parse_number(ptr);
 252             }
 253             else {
 254                 /* Specified value and address, but no count. Only one. */
 255                 count = -1;
 256             }
 257         }
 258         else {
 259             /* Specified a value, but no address, so search same range. */
 260             addr = start;
 261             count = lastcount;
 262         }
 263     }
 264     else {
 265         /* Specified nothing, search again for val. */
 266         val = lastval;
 267         addr = end;
 268         count = lastcount;
 269     }
 270
 271     lastval = val;
 272     start = end = addr;
 273     lastcount = count;
 274
 275     printf("searching for 0x%x at %p\n", val, (void*)(uword_t)end);
 276
 277     while (search_for_type(val, &end, &count)) {
 278         printf("found 0x%x at %p:\n", val, (void*)(uword_t)end);
 279         obj = *end;
 280         addr = end;
 281         end += 2;
 282         if (widetag_of(obj) == SIMPLE_FUN_WIDETAG) {
 283             print((uword_t)addr | FUN_POINTER_LOWTAG);
 284         } else if (other_immediate_lowtag_p(obj)) {
 285             print((lispobj)addr | OTHER_POINTER_LOWTAG);
 286         } else {
 287             print((lispobj)addr);
 288         } if (count == -1) {
 289             return;
 290         }
 291     }
 292 }
 293
 294 /* (There used to be call_cmd() here, to call known-at-cold-init-time
 295  * Lisp functions from ldb, but it bitrotted and was deleted in
 296  * sbcl-0.7.5.1. See older CVS versions if you want to resuscitate
 297  * it.) */
 298
 299 static void
 300 flush_cmd(char **ptr)
 301 {
 302     flush_vars();
 303 }
 304
 305 static void
 306 quit_cmd(char **ptr)
 307 {
 308     char buf[10];
 309
 310     printf("Really quit? [y] ");
 311     fflush(stdout);
 312     if (fgets(buf, sizeof(buf), ldb_in)) {
 313         if (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')
 314             exit(1);
 315     } else {
 316         printf("\nUnable to read response, assuming y.\n");
 317         exit(1);
 318     }
 319 }
 320
 321 static void
 322 help_cmd(char **ptr)
 323 {
 324     struct cmd *cmd;
 325
 326     for (cmd = supported_cmds; cmd->cmd != NULL; cmd++)
 327         if (cmd->help != NULL)
 328             printf("%s\t%s\n", cmd->cmd, cmd->help);
 329 }
 330
 331 static int done;
 332
 333 static void
 334 exit_cmd(char **ptr)
 335 {
 336     done = 1;
 337 }
 338
 339 static void
 340 purify_cmd(char **ptr)
 341 {
 342     purify(NIL, NIL);
 343 }
 344
 345 static void
 346 print_context(os_context_t *context)
 347 {
 348     int i;
 349
 350     for (i = 0; i < NREGS; i++) {
 351         printf("%s:\t", lisp_register_names[i]);
 352 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 353         brief_print((lispobj)(*os_context_register_addr(context, i*2)));
 354 #else
 355         brief_print((lispobj)(*os_context_register_addr(context,i)));
 356 #endif
 357     }
 358 #if defined(LISP_FEATURE_DARWIN) && defined(LISP_FEATURE_PPC)
 359     printf("DAR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 41)));
 360     printf("DSISR:\t\t 0x%08lx\n", (unsigned long)(*os_context_register_addr(context, 42)));
 361 #endif
 362     printf("PC:\t\t  0x%08lx\n",
 363            (unsigned long)(*os_context_pc_addr(context)));
 364 }
 365
 366 static void
 367 print_context_cmd(char **ptr)
 368 {
 369     int free_ici;
 370     struct thread *thread=arch_os_get_current_thread();
 371
 372     free_ici = fixnum_value(read_TLS(FREE_INTERRUPT_CONTEXT_INDEX,thread));
 373
 374     if (more_p(ptr)) {
 375         int index;
 376
 377         index = parse_number(ptr);
 378
 379         if ((index >= 0) && (index < free_ici)) {
 380             printf("There are %d interrupt contexts.\n", free_ici);
 381             printf("printing context %d\n", index);
 382             print_context(thread->interrupt_contexts[index]);
 383         } else {
 384             printf("There aren't that many/few contexts.\n");
 385             printf("There are %d interrupt contexts.\n", free_ici);
 386         }
 387     } else {
 388         if (free_ici == 0)
 389             printf("There are no interrupt contexts!\n");
 390         else {
 391             printf("There are %d interrupt contexts.\n", free_ici);
 392             printf("printing context %d\n", free_ici - 1);
 393             print_context(thread->interrupt_contexts[free_ici - 1]);
 394         }
 395     }
 396 }
 397
 398 static void
 399 backtrace_cmd(char **ptr)
 400 {
 401     void lisp_backtrace(int frames);
 402     int n;
 403
 404     if (more_p(ptr))
 405         n = parse_number(ptr);
 406     else
 407         n = 100;
 408
 409     printf("Backtrace:\n");
 410     lisp_backtrace(n);
 411 }
 412
 413 static void
 414 catchers_cmd(char **ptr)
 415 {
 416     struct catch_block *catch = (struct catch_block *)
 417         read_TLS(CURRENT_CATCH_BLOCK, arch_os_get_current_thread());
 418
 419     if (catch == NULL)
 420         printf("There are no active catchers!\n");
 421     else {
 422         while (catch != NULL) {
 423             printf("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\t"
 424                    "code: 0x%08lX\n\tentry: 0x%08lX\n\ttag: ",
 425                    (long unsigned)catch,
 426                    (long unsigned)(catch->uwp),
 427                    (long unsigned)(catch->cfp),
 428 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 429                    (long unsigned)component_ptr_from_pc((void*)catch->entry_pc)
 430                        + OTHER_POINTER_LOWTAG,
 431 #else
 432                    (long unsigned)(catch->code),
 433 #endif
 434                    (long unsigned)(catch->entry_pc));
 435             brief_print((lispobj)catch->tag);
 436             catch = catch->previous_catch;
 437         }
 438     }
 439 }
 440
 441 static void
 442 grab_sigs_cmd(char **ptr)
 443 {
 444     extern void sigint_init(void);
 445
 446     printf("Grabbing signals.\n");
 447     sigint_init();
 448 }
 449
 450 static void
 451 sub_monitor(void)
 452 {
 453     struct cmd *cmd, *found;
 454     char buf[256];
 455     char *line, *ptr, *token;
 456     int ambig;
 457
 458     if (!ldb_in) {
 459 #ifndef LISP_FEATURE_WIN32
 460         ldb_in = fopen("/dev/tty","r+");
 461         if (ldb_in == NULL) {
 462             perror("Error opening /dev/tty");
 463             ldb_in = stdin;
 464         }
 465 #else
 466         ldb_in = stdin;
 467 #endif
 468         ldb_in_fd = fileno(ldb_in);
 469     }
 470
 471     while (!done) {
 472         printf("ldb> ");
 473         fflush(stdout);
 474         line = fgets(buf, sizeof(buf), ldb_in);
 475         if (line == NULL) {
 476             exit(1);
 477         }
 478         ptr = line;
 479         if ((token = parse_token(&ptr)) == NULL)
 480             continue;
 481         ambig = 0;
 482         found = NULL;
 483         for (cmd = supported_cmds; cmd->cmd != NULL; cmd++) {
 484             if (strcmp(token, cmd->cmd) == 0) {
 485                 found = cmd;
 486                 ambig = 0;
 487                 break;
 488             }
 489             else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
 490                 if (found)
 491                     ambig = 1;
 492                 else
 493                     found = cmd;
 494             }
 495         }
 496         if (ambig)
 497             printf("``%s'' is ambiguous.\n", token);
 498         else if (found == NULL)
 499             printf("unknown command: ``%s''\n", token);
 500         else {
 501             reset_printer();
 502             (*found->fn)(&ptr);
 503         }
 504     }
 505 }
 506
 507 void
 508 ldb_monitor()
 509 {
 510     jmp_buf oldbuf;
 511
 512     bcopy(curbuf, oldbuf, sizeof(oldbuf));
 513
 514     printf("Welcome to LDB, a low-level debugger for the Lisp runtime environment.\n");
 515
 516     setjmp(curbuf);
 517
 518     sub_monitor();
 519
 520     done = 0;
 521
 522     bcopy(oldbuf, curbuf, sizeof(curbuf));
 523 }
 524
 525 void
 526 throw_to_monitor()
 527 {
 528     longjmp(curbuf, 1);
 529 }
 530
 531 /* what we do when things go badly wrong at a low level */
 532 void
 533 monitor_or_something()
 534 {
 535     ldb_monitor();
 536 }