src/runtime/save.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 #ifndef LISP_FEATURE_WIN32
  13 #include <sys/types.h>
  14 #include <sys/stat.h>
  15 #endif
  16 #include <stdlib.h>
  17 #include <stdio.h>
  18 #include <string.h>
  19 #include <signal.h>
  20 #include <sys/file.h>
  21
  22 #include "sbcl.h"
  23 #include "runtime.h"
  24 #include "os.h"
  25 #include "core.h"
  26 #include "globals.h"
  27 #include "save.h"
  28 #include "dynbind.h"
  29 #include "lispregs.h"
  30 #include "validate.h"
  31 #include "gc-internal.h"
  32 #include "thread.h"
  33
  34 #include "genesis/static-symbols.h"
  35 #include "genesis/symbol.h"
  36
  37 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
  38 #include "genesis/lutex.h"
  39 #endif
  40
  41 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
  42 # include <zlib.h>
  43 #endif
  44
  45
  46 /* write_runtime_options uses a simple serialization scheme that
  47  * consists of one word of magic, one word indicating whether options
  48  * are actually saved, and one word per struct field. */
  49 static void
  50 write_runtime_options(FILE *file, struct runtime_options *options)
  51 {
  52     size_t optarray[RUNTIME_OPTIONS_WORDS];
  53
  54     memset(&optarray, 0, sizeof(optarray));
  55     optarray[0] = RUNTIME_OPTIONS_MAGIC;
  56
  57     if (options != NULL) {
  58         /* optarray[1] is a flag indicating that options are present */
  59         optarray[1] = 1;
  60         optarray[2] = options->dynamic_space_size;
  61         optarray[3] = options->thread_control_stack_size;
  62     }
  63
  64     if (RUNTIME_OPTIONS_WORDS !=
  65         fwrite(optarray, sizeof(size_t), RUNTIME_OPTIONS_WORDS, file)) {
  66         perror("Error writing runtime options to file");
  67     }
  68 }
  69
  70 static void
  71 write_lispobj(lispobj obj, FILE *file)
  72 {
  73     if (1 != fwrite(&obj, sizeof(lispobj), 1, file)) {
  74         perror("Error writing to file");
  75     }
  76 }
  77
  78 static void
  79 write_bytes_to_file(FILE * file, char *addr, long bytes, int compression)
  80 {
  81     if (compression == COMPRESSION_LEVEL_NONE) {
  82         while (bytes > 0) {
  83             long count = fwrite(addr, 1, bytes, file);
  84             if (count > 0) {
  85                 bytes -= count;
  86                 addr += count;
  87             }
  88             else {
  89                 perror("error writing to save file");
  90                 bytes = 0;
  91             }
  92         }
  93 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
  94     } else if ((compression >= -1) && (compression <= 9)) {
  95 # define ZLIB_BUFFER_SIZE (1u<<16)
  96         z_stream stream;
  97         unsigned char buf[ZLIB_BUFFER_SIZE];
  98         unsigned char * written, * end;
  99         long total_written = 0;
 100         int ret;
 101         stream.zalloc = NULL;
 102         stream.zfree = NULL;
 103         stream.opaque = NULL;
 104         stream.avail_in = bytes;
 105         stream.next_in  = (void*)addr;
 106         ret = deflateInit(&stream, compression);
 107         if (ret != Z_OK)
 108             lose("deflateInit: %i\n", ret);
 109         do {
 110             stream.avail_out = sizeof(buf);
 111             stream.next_out = buf;
 112             ret = deflate(&stream, Z_FINISH);
 113             if (ret < 0) lose("zlib deflate error: %i... exiting\n", ret);
 114             written = buf;
 115             end     = buf+sizeof(buf)-stream.avail_out;
 116             total_written += end - written;
 117             while (written < end) {
 118                 long count = fwrite(written, 1, end-written, file);
 119                 if (count > 0) {
 120                     written += count;
 121                 } else {
 122                     lose("unable to write to core file\n");
 123                 }
 124             }
 125         } while (stream.avail_out == 0);
 126         deflateEnd(&stream);
 127         printf("compressed %lu bytes into %lu at level %i\n",
 128                bytes, total_written, compression);
 129 # undef ZLIB_BUFFER_SIZE
 130 #endif
 131     } else {
 132 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
 133         lose("Unknown core compression level %i, exiting\n", compression);
 134 #else
 135         lose("zlib-compressed core support not built in this runtime\n");
 136 #endif
 137     }
 138
 139     fflush(file);
 140 };
 141
 142
 143 static long
 144 write_and_compress_bytes(FILE *file, char *addr, long bytes, os_vm_offset_t file_offset,
 145                          int compression)
 146 {
 147     long here, data;
 148
 149     bytes = (bytes+os_vm_page_size-1)&~(os_vm_page_size-1);
 150
 151 #ifdef LISP_FEATURE_WIN32
 152     long count;
 153     /* touch every single page in the space to force it to be mapped. */
 154     for (count = 0; count < bytes; count += 0x1000) {
 155         volatile int temp = addr[count];
 156     }
 157 #endif
 158
 159     fflush(file);
 160     here = ftell(file);
 161     fseek(file, 0, SEEK_END);
 162     data = (ftell(file)+os_vm_page_size-1)&~(os_vm_page_size-1);
 163     fseek(file, data, SEEK_SET);
 164     write_bytes_to_file(file, addr, bytes, compression);
 165     fseek(file, here, SEEK_SET);
 166     return ((data - file_offset) / os_vm_page_size) - 1;
 167 }
 168
 169 static long
 170 write_bytes(FILE *file, char *addr, long bytes, os_vm_offset_t file_offset)
 171 {
 172     return write_and_compress_bytes(file, addr, bytes, file_offset,
 173                                     COMPRESSION_LEVEL_NONE);
 174 }
 175
 176 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
 177 /* saving lutexes in the core */
 178 static void **lutex_addresses;
 179 static long n_lutexes = 0;
 180 static long max_lutexes = 0;
 181
 182 static long
 183 default_scan_action(lispobj *obj)
 184 {
 185     return (sizetab[widetag_of(*obj)])(obj);
 186 }
 187
 188 static long
 189 lutex_scan_action(lispobj *obj)
 190 {
 191     /* note the address of the lutex */
 192     if(n_lutexes >= max_lutexes) {
 193         max_lutexes *= 2;
 194         lutex_addresses = realloc(lutex_addresses, max_lutexes * sizeof(void *));
 195         gc_assert(lutex_addresses);
 196     }
 197
 198     lutex_addresses[n_lutexes++] = obj;
 199
 200     return (*sizetab[widetag_of(*obj)])(obj);
 201 }
 202
 203 typedef long (*scan_table[256])(lispobj *obj);
 204
 205 static void
 206 scan_objects(lispobj *start, long n_words, scan_table table)
 207 {
 208     lispobj *end = start + n_words;
 209     lispobj *object_ptr;
 210     long n_words_scanned;
 211     for (object_ptr = start;
 212          object_ptr < end;
 213          object_ptr += n_words_scanned) {
 214         lispobj obj = *object_ptr;
 215
 216         n_words_scanned = (table[widetag_of(obj)])(object_ptr);
 217     }
 218 }
 219
 220 static void
 221 scan_for_lutexes(lispobj *addr, long n_words)
 222 {
 223     static int initialized = 0;
 224     static scan_table lutex_scan_table;
 225
 226     if (!initialized) {
 227         int i;
 228
 229         /* allocate a little space to get started */
 230         lutex_addresses = malloc(16*sizeof(void *));
 231         gc_assert(lutex_addresses);
 232         max_lutexes = 16;
 233
 234         /* initialize the mapping table */
 235         for(i = 0; i < ((sizeof lutex_scan_table)/(sizeof lutex_scan_table[0])); ++i) {
 236             lutex_scan_table[i] = default_scan_action;
 237         }
 238
 239         lutex_scan_table[LUTEX_WIDETAG] = lutex_scan_action;
 240
 241         initialized = 1;
 242     }
 243
 244     /* do the scan */
 245     scan_objects(addr, n_words, lutex_scan_table);
 246 }
 247 #endif
 248
 249 static void
 250 output_space(FILE *file, int id, lispobj *addr, lispobj *end,
 251              os_vm_offset_t file_offset,
 252              int core_compression_level)
 253 {
 254     size_t words, bytes, data, compressed_flag;
 255     static char *names[] = {NULL, "dynamic", "static", "read-only"};
 256
 257     compressed_flag
 258             = ((core_compression_level != COMPRESSION_LEVEL_NONE)
 259                ? DEFLATED_CORE_SPACE_ID_FLAG : 0);
 260
 261     write_lispobj(id | compressed_flag, file);
 262     words = end - addr;
 263     write_lispobj(words, file);
 264
 265     bytes = words * sizeof(lispobj);
 266
 267 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
 268     printf("scanning space for lutexes...\n");
 269     scan_for_lutexes((void *)addr, words);
 270 #endif
 271
 272     printf("writing %lu bytes from the %s space at 0x%08lx\n",
 273            (unsigned long)bytes, names[id], (unsigned long)addr);
 274
 275     data = write_and_compress_bytes(file, (char *)addr, bytes, file_offset,
 276                                     core_compression_level);
 277
 278     write_lispobj(data, file);
 279     write_lispobj((long)addr / os_vm_page_size, file);
 280     write_lispobj((bytes + os_vm_page_size - 1) / os_vm_page_size, file);
 281 }
 282
 283 FILE *
 284 open_core_for_saving(char *filename)
 285 {
 286     /* Open the output file. We don't actually need the file yet, but
 287      * the fopen() might fail for some reason, and we want to detect
 288      * that and back out before we do anything irreversible. */
 289     unlink(filename);
 290     return fopen(filename, "wb");
 291 }
 292
 293 boolean
 294 save_to_filehandle(FILE *file, char *filename, lispobj init_function,
 295                    boolean make_executable,
 296                    boolean save_runtime_options,
 297                    int core_compression_level)
 298 {
 299     struct thread *th;
 300     os_vm_offset_t core_start_pos;
 301
 302     /* Smash the enclosing state. (Once we do this, there's no good
 303      * way to go back, which is a sufficient reason that this ends up
 304      * being SAVE-LISP-AND-DIE instead of SAVE-LISP-AND-GO-ON). */
 305     printf("[undoing binding stack and other enclosing state... ");
 306     fflush(stdout);
 307     for_each_thread(th) {       /* XXX really? */
 308         unbind_to_here((lispobj *)th->binding_stack_start,th);
 309         SetSymbolValue(CURRENT_CATCH_BLOCK, 0,th);
 310         SetSymbolValue(CURRENT_UNWIND_PROTECT_BLOCK, 0,th);
 311     }
 312     printf("done]\n");
 313     fflush(stdout);
 314
 315     /* (Now we can actually start copying ourselves into the output file.) */
 316
 317     printf("[saving current Lisp image into %s:\n", filename);
 318     fflush(stdout);
 319
 320     core_start_pos = ftell(file);
 321     write_lispobj(CORE_MAGIC, file);
 322
 323     write_lispobj(VERSION_CORE_ENTRY_TYPE_CODE, file);
 324     write_lispobj(3, file);
 325     write_lispobj(SBCL_CORE_VERSION_INTEGER, file);
 326
 327     write_lispobj(BUILD_ID_CORE_ENTRY_TYPE_CODE, file);
 328     write_lispobj(/* (We're writing the word count of the entry here, and the 2
 329           * term is one word for the leading BUILD_ID_CORE_ENTRY_TYPE_CODE
 330           * word and one word where we store the count itself.) */
 331          2 + strlen((const char *)build_id),
 332          file);
 333     {
 334         unsigned char *p;
 335         for (p = (unsigned char *)build_id; *p; ++p)
 336             write_lispobj(*p, file);
 337     }
 338
 339     write_lispobj(NEW_DIRECTORY_CORE_ENTRY_TYPE_CODE, file);
 340     write_lispobj(/* (word count = 3 spaces described by 5 words each, plus the
 341           * entry type code, plus this count itself) */
 342          (5*3)+2, file);
 343     output_space(file,
 344                  READ_ONLY_CORE_SPACE_ID,
 345                  (lispobj *)READ_ONLY_SPACE_START,
 346                  (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0),
 347                  core_start_pos,
 348                  core_compression_level);
 349     output_space(file,
 350                  STATIC_CORE_SPACE_ID,
 351                  (lispobj *)STATIC_SPACE_START,
 352                  (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0),
 353                  core_start_pos,
 354                  core_compression_level);
 355 #ifdef LISP_FEATURE_GENCGC
 356     /* Flush the current_region, updating the tables. */
 357     gc_alloc_update_all_page_tables();
 358     update_dynamic_space_free_pointer();
 359 #endif
 360 #ifdef reg_ALLOC
 361 #ifdef LISP_FEATURE_GENCGC
 362     output_space(file,
 363                  DYNAMIC_CORE_SPACE_ID,
 364                  (lispobj *)DYNAMIC_SPACE_START,
 365                  dynamic_space_free_pointer,
 366                  core_start_pos,
 367                  core_compression_level);
 368 #else
 369     output_space(file,
 370                  DYNAMIC_CORE_SPACE_ID,
 371                  (lispobj *)current_dynamic_space,
 372                  dynamic_space_free_pointer,
 373                  core_start_pos,
 374                  core_compression_level);
 375 #endif
 376 #else
 377     output_space(file,
 378                  DYNAMIC_CORE_SPACE_ID,
 379                  (lispobj *)DYNAMIC_SPACE_START,
 380                  (lispobj *)SymbolValue(ALLOCATION_POINTER,0),
 381                  core_start_pos,
 382                  core_compression_level);
 383 #endif
 384
 385     write_lispobj(INITIAL_FUN_CORE_ENTRY_TYPE_CODE, file);
 386     write_lispobj(3, file);
 387     write_lispobj(init_function, file);
 388
 389 #ifdef LISP_FEATURE_GENCGC
 390     {
 391         size_t size = (last_free_page*sizeof(long)+os_vm_page_size-1)
 392             &~(os_vm_page_size-1);
 393         unsigned long *data = calloc(size, 1);
 394         if (data) {
 395             unsigned long word;
 396             long offset;
 397             int i;
 398             for (i = 0; i < last_free_page; i++) {
 399                 /* Thanks to alignment requirements, the two low bits
 400                  * are always zero, so we can use them to store the
 401                  * allocation type -- region is always closed, so only
 402                  * the two low bits of allocation flags matter. */
 403                 word = page_table[i].region_start_offset;
 404                 gc_assert((word & 0x03) == 0);
 405                 data[i] = word | (0x03 & page_table[i].allocated);
 406             }
 407             write_lispobj(PAGE_TABLE_CORE_ENTRY_TYPE_CODE, file);
 408             write_lispobj(4, file);
 409             write_lispobj(size, file);
 410             offset = write_bytes(file, (char *)data, size, core_start_pos);
 411             write_lispobj(offset, file);
 412         }
 413     }
 414 #endif
 415
 416 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
 417     if(n_lutexes > 0) {
 418         long offset;
 419         printf("writing %ld lutexes to the core...\n", n_lutexes);
 420         write_lispobj(LUTEX_TABLE_CORE_ENTRY_TYPE_CODE, file);
 421         /* word count of the entry */
 422         write_lispobj(4, file);
 423         /* indicate how many lutexes we saved */
 424         write_lispobj(n_lutexes, file);
 425         /* save the lutexes */
 426         offset = write_bytes(file, (char *) lutex_addresses,
 427                              n_lutexes * sizeof(*lutex_addresses),
 428                              core_start_pos);
 429
 430         write_lispobj(offset, file);
 431     }
 432 #endif
 433
 434     write_lispobj(END_CORE_ENTRY_TYPE_CODE, file);
 435
 436     /* Write a trailing header, ignored when parsing the core normally.
 437      * This is used to locate the start of the core when the runtime is
 438      * prepended to it. */
 439     fseek(file, 0, SEEK_END);
 440
 441     /* If NULL runtime options are passed to write_runtime_options,
 442      * command-line processing is performed as normal in the SBCL
 443      * executable. Otherwise, the saved runtime options are used and
 444      * all command-line arguments are available to Lisp in
 445      * SB-EXT:*POSIX-ARGV*. */
 446     write_runtime_options(file,
 447                           (save_runtime_options ? runtime_options : NULL));
 448
 449     if (1 != fwrite(&core_start_pos, sizeof(os_vm_offset_t), 1, file)) {
 450         perror("Error writing core starting position to file");
 451         fclose(file);
 452     } else {
 453         write_lispobj(CORE_MAGIC, file);
 454         fclose(file);
 455     }
 456
 457 #ifndef LISP_FEATURE_WIN32
 458     if (make_executable)
 459         chmod (filename, 0755);
 460 #endif
 461
 462     printf("done]\n");
 463     exit(0);
 464 }
 465
 466 /* Check if the build_id for the current runtime is present in a
 467  * buffer. */
 468 int
 469 check_runtime_build_id(void *buf, size_t size)
 470 {
 471     size_t idlen;
 472     char *pos;
 473
 474     idlen = strlen(build_id) - 1;
 475     while ((pos = memchr(buf, build_id[0], size)) != NULL) {
 476         size -= (pos + 1) - (char *)buf;
 477         buf = (pos + 1);
 478         if (idlen <= size && memcmp(buf, build_id + 1, idlen) == 0)
 479             return 1;
 480     }
 481
 482     return 0;
 483 }
 484
 485 /* Slurp the executable portion of the runtime into a malloced buffer
 486  * and return it.  Places the size in bytes of the runtime into
 487  * 'size_out'.  Returns NULL if the runtime cannot be loaded from
 488  * 'runtime_path'. */
 489 void *
 490 load_runtime(char *runtime_path, size_t *size_out)
 491 {
 492     void *buf = NULL;
 493     FILE *input = NULL;
 494     size_t size, count;
 495     os_vm_offset_t core_offset;
 496
 497     core_offset = search_for_embedded_core (runtime_path);
 498     if ((input = fopen(runtime_path, "rb")) == NULL) {
 499         fprintf(stderr, "Unable to open runtime: %s\n", runtime_path);
 500         goto lose;
 501     }
 502
 503     fseek(input, 0, SEEK_END);
 504     size = (size_t) ftell(input);
 505     fseek(input, 0, SEEK_SET);
 506
 507     if (core_offset != -1 && size > core_offset)
 508         size = core_offset;
 509
 510     buf = successful_malloc(size);
 511     if ((count = fread(buf, 1, size, input)) != size) {
 512         fprintf(stderr, "Premature EOF while reading runtime.\n");
 513         goto lose;
 514     }
 515
 516     if (!check_runtime_build_id(buf, size)) {
 517         fprintf(stderr, "Failed to locate current build_id in runtime: %s\n",
 518             runtime_path);
 519         goto lose;
 520     }
 521
 522     fclose(input);
 523     *size_out = size;
 524     return buf;
 525
 526 lose:
 527     if (input != NULL)
 528         fclose(input);
 529     if (buf != NULL)
 530         free(buf);
 531     return NULL;
 532 }
 533
 534 boolean
 535 save_runtime_to_filehandle(FILE *output, void *runtime, size_t runtime_size)
 536 {
 537     size_t padding;
 538     void *padbytes;
 539
 540     if (runtime_size != fwrite(runtime, 1, runtime_size, output)) {
 541         perror("Error saving runtime");
 542         return 0;
 543     }
 544
 545     padding = (os_vm_page_size - (runtime_size % os_vm_page_size)) & ~os_vm_page_size;
 546     if (padding > 0) {
 547         padbytes = successful_malloc(padding);
 548         memset(padbytes, 0, padding);
 549         if (padding != fwrite(padbytes, 1, padding, output)) {
 550             perror("Error saving runtime");
 551             free(padbytes);
 552             return 0;
 553         }
 554         free(padbytes);
 555     }
 556
 557     return 1;
 558 }
 559
 560 FILE *
 561 prepare_to_save(char *filename, boolean prepend_runtime, void **runtime_bytes,
 562                 size_t *runtime_size)
 563 {
 564     FILE *file;
 565     char *runtime_path;
 566
 567     if (prepend_runtime) {
 568         runtime_path = os_get_runtime_executable_path(0);
 569
 570         if (runtime_path == NULL && saved_runtime_path == NULL) {
 571             fprintf(stderr, "Unable to get default runtime path.\n");
 572             return NULL;
 573         }
 574
 575         if (runtime_path == NULL)
 576             *runtime_bytes = load_runtime(saved_runtime_path, runtime_size);
 577         else {
 578             *runtime_bytes = load_runtime(runtime_path, runtime_size);
 579             free(runtime_path);
 580         }
 581
 582         if (*runtime_bytes == NULL)
 583             return 0;
 584     }
 585
 586     file = open_core_for_saving(filename);
 587     if (file == NULL) {
 588         free(*runtime_bytes);
 589         perror(filename);
 590         return NULL;
 591     }
 592
 593     return file;
 594 }
 595
 596 boolean
 597 save(char *filename, lispobj init_function, boolean prepend_runtime,
 598      boolean save_runtime_options, boolean compressed, int compression_level)
 599 {
 600     FILE *file;
 601     void *runtime_bytes = NULL;
 602     size_t runtime_size;
 603
 604     file = prepare_to_save(filename, prepend_runtime, &runtime_bytes, &runtime_size);
 605     if (file == NULL)
 606         return 1;
 607
 608     if (prepend_runtime)
 609         save_runtime_to_filehandle(file, runtime_bytes, runtime_size);
 610
 611     return save_to_filehandle(file, filename, init_function, prepend_runtime,
 612                               save_runtime_options,
 613                               compressed ? compressed : COMPRESSION_LEVEL_NONE);
 614 }