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