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 static void
  42 write_lispobj(lispobj obj, FILE *file)
  43 {
  44     fwrite(&obj, sizeof(lispobj), 1, file);
  45 }
  46
  47 static long
  48 write_bytes(FILE *file, char *addr, long bytes, os_vm_offset_t file_offset)
  49 {
  50     long count, here, data;
  51
  52     bytes = (bytes+os_vm_page_size-1)&~(os_vm_page_size-1);
  53
  54 #ifdef LISP_FEATURE_WIN32
  55     /* touch every single page in the space to force it to be mapped. */
  56     for (count = 0; count < bytes; count += 0x1000) {
  57         volatile int temp = addr[count];
  58     }
  59 #endif
  60
  61     fflush(file);
  62     here = ftell(file);
  63     fseek(file, 0, SEEK_END);
  64     data = (ftell(file)+os_vm_page_size-1)&~(os_vm_page_size-1);
  65     fseek(file, data, SEEK_SET);
  66
  67     while (bytes > 0) {
  68         count = fwrite(addr, 1, bytes, file);
  69         if (count > 0) {
  70             bytes -= count;
  71             addr += count;
  72         }
  73         else {
  74             perror("error writing to save file");
  75             bytes = 0;
  76         }
  77     }
  78     fflush(file);
  79     fseek(file, here, SEEK_SET);
  80     return ((data - file_offset) / os_vm_page_size) - 1;
  81 }
  82
  83 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
  84 /* saving lutexes in the core */
  85 static void **lutex_addresses;
  86 static long n_lutexes = 0;
  87 static long max_lutexes = 0;
  88
  89 static long
  90 default_scan_action(lispobj *obj)
  91 {
  92     return (sizetab[widetag_of(*obj)])(obj);
  93 }
  94
  95 static long
  96 lutex_scan_action(lispobj *obj)
  97 {
  98     /* note the address of the lutex */
  99     if(n_lutexes >= max_lutexes) {
 100         max_lutexes *= 2;
 101         lutex_addresses = realloc(lutex_addresses, max_lutexes * sizeof(void *));
 102         gc_assert(lutex_addresses);
 103     }
 104
 105     lutex_addresses[n_lutexes++] = obj;
 106
 107     return (*sizetab[widetag_of(*obj)])(obj);
 108 }
 109
 110 typedef long (*scan_table[256])(lispobj *obj);
 111
 112 static void
 113 scan_objects(lispobj *start, long n_words, scan_table table)
 114 {
 115     lispobj *end = start + n_words;
 116     lispobj *object_ptr;
 117     long n_words_scanned;
 118     for (object_ptr = start;
 119          object_ptr < end;
 120          object_ptr += n_words_scanned) {
 121         lispobj obj = *object_ptr;
 122
 123         n_words_scanned = (table[widetag_of(obj)])(object_ptr);
 124     }
 125 }
 126
 127 static void
 128 scan_for_lutexes(lispobj *addr, long n_words)
 129 {
 130     static int initialized = 0;
 131     static scan_table lutex_scan_table;
 132
 133     if (!initialized) {
 134         int i;
 135
 136         /* allocate a little space to get started */
 137         lutex_addresses = malloc(16*sizeof(void *));
 138         gc_assert(lutex_addresses);
 139         max_lutexes = 16;
 140
 141         /* initialize the mapping table */
 142         for(i = 0; i < ((sizeof lutex_scan_table)/(sizeof lutex_scan_table[0])); ++i) {
 143             lutex_scan_table[i] = default_scan_action;
 144         }
 145
 146         lutex_scan_table[LUTEX_WIDETAG] = lutex_scan_action;
 147
 148         initialized = 1;
 149     }
 150
 151     /* do the scan */
 152     scan_objects(addr, n_words, lutex_scan_table);
 153 }
 154 #endif
 155
 156 static void
 157 output_space(FILE *file, int id, lispobj *addr, lispobj *end, os_vm_offset_t file_offset)
 158 {
 159     size_t words, bytes, data;
 160     static char *names[] = {NULL, "dynamic", "static", "read-only"};
 161
 162     write_lispobj(id, file);
 163     words = end - addr;
 164     write_lispobj(words, file);
 165
 166     bytes = words * sizeof(lispobj);
 167
 168 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
 169     printf("scanning space for lutexes...\n");
 170     scan_for_lutexes((char *)addr, words);
 171 #endif
 172
 173     printf("writing %ld bytes from the %s space at 0x%08lx\n",
 174            bytes, names[id], (unsigned long)addr);
 175
 176     data = write_bytes(file, (char *)addr, bytes, file_offset);
 177
 178     write_lispobj(data, file);
 179     write_lispobj((long)addr / os_vm_page_size, file);
 180     write_lispobj((bytes + os_vm_page_size - 1) / os_vm_page_size, file);
 181 }
 182
 183 FILE *
 184 open_core_for_saving(char *filename)
 185 {
 186     /* Open the output file. We don't actually need the file yet, but
 187      * the fopen() might fail for some reason, and we want to detect
 188      * that and back out before we do anything irreversible. */
 189     unlink(filename);
 190     return fopen(filename, "wb");
 191 }
 192
 193 boolean
 194 save_to_filehandle(FILE *file, char *filename, lispobj init_function,
 195                    boolean make_executable)
 196 {
 197     struct thread *th;
 198     os_vm_offset_t core_start_pos, core_end_pos, core_size;
 199
 200     /* Smash the enclosing state. (Once we do this, there's no good
 201      * way to go back, which is a sufficient reason that this ends up
 202      * being SAVE-LISP-AND-DIE instead of SAVE-LISP-AND-GO-ON). */
 203     printf("[undoing binding stack and other enclosing state... ");
 204     fflush(stdout);
 205     for_each_thread(th) {       /* XXX really? */
 206         unbind_to_here((lispobj *)th->binding_stack_start,th);
 207         SetSymbolValue(CURRENT_CATCH_BLOCK, 0,th);
 208         SetSymbolValue(CURRENT_UNWIND_PROTECT_BLOCK, 0,th);
 209     }
 210     printf("done]\n");
 211     fflush(stdout);
 212
 213     /* (Now we can actually start copying ourselves into the output file.) */
 214
 215     printf("[saving current Lisp image into %s:\n", filename);
 216     fflush(stdout);
 217
 218     core_start_pos = ftell(file);
 219     write_lispobj(CORE_MAGIC, file);
 220
 221     write_lispobj(VERSION_CORE_ENTRY_TYPE_CODE, file);
 222     write_lispobj(3, file);
 223     write_lispobj(SBCL_CORE_VERSION_INTEGER, file);
 224
 225     write_lispobj(BUILD_ID_CORE_ENTRY_TYPE_CODE, file);
 226     write_lispobj(/* (We're writing the word count of the entry here, and the 2
 227           * term is one word for the leading BUILD_ID_CORE_ENTRY_TYPE_CODE
 228           * word and one word where we store the count itself.) */
 229          2 + strlen((const char *)build_id),
 230          file);
 231     {
 232         unsigned char *p;
 233         for (p = build_id; *p; ++p)
 234             write_lispobj(*p, file);
 235     }
 236
 237     write_lispobj(NEW_DIRECTORY_CORE_ENTRY_TYPE_CODE, file);
 238     write_lispobj(/* (word count = 3 spaces described by 5 words each, plus the
 239           * entry type code, plus this count itself) */
 240          (5*3)+2, file);
 241     output_space(file,
 242                  READ_ONLY_CORE_SPACE_ID,
 243                  (lispobj *)READ_ONLY_SPACE_START,
 244                  (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0),
 245                  core_start_pos);
 246     output_space(file,
 247                  STATIC_CORE_SPACE_ID,
 248                  (lispobj *)STATIC_SPACE_START,
 249                  (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0),
 250                  core_start_pos);
 251 #ifdef LISP_FEATURE_GENCGC
 252     /* Flush the current_region, updating the tables. */
 253     gc_alloc_update_all_page_tables();
 254     update_dynamic_space_free_pointer();
 255 #endif
 256 #ifdef reg_ALLOC
 257 #ifdef LISP_FEATURE_GENCGC
 258     output_space(file,
 259                  DYNAMIC_CORE_SPACE_ID,
 260                  (lispobj *)DYNAMIC_SPACE_START,
 261                  dynamic_space_free_pointer,
 262                  core_start_pos);
 263 #else
 264     output_space(file,
 265                  DYNAMIC_CORE_SPACE_ID,
 266                  (lispobj *)current_dynamic_space,
 267                  dynamic_space_free_pointer,
 268                  core_start_pos);
 269 #endif
 270 #else
 271     output_space(file,
 272                  DYNAMIC_CORE_SPACE_ID,
 273                  (lispobj *)DYNAMIC_SPACE_START,
 274                  (lispobj *)SymbolValue(ALLOCATION_POINTER,0),
 275                  core_start_pos);
 276 #endif
 277
 278     write_lispobj(INITIAL_FUN_CORE_ENTRY_TYPE_CODE, file);
 279     write_lispobj(3, file);
 280     write_lispobj(init_function, file);
 281
 282 #ifdef LISP_FEATURE_GENCGC
 283     {
 284         size_t size = (last_free_page*sizeof(long)+os_vm_page_size-1)
 285             &~(os_vm_page_size-1);
 286         long *data = calloc(size, 1);
 287         if (data) {
 288             long offset;
 289             int i;
 290             for (i = 0; i < last_free_page; i++) {
 291                 data[i] = page_table[i].first_object_offset;
 292             }
 293             write_lispobj(PAGE_TABLE_CORE_ENTRY_TYPE_CODE, file);
 294             write_lispobj(4, file);
 295             write_lispobj(size, file);
 296             offset = write_bytes(file, (char *) data, size, core_start_pos);
 297             write_lispobj(offset, file);
 298         }
 299     }
 300 #endif
 301
 302 #if defined(LISP_FEATURE_SB_THREAD) && defined(LISP_FEATURE_SB_LUTEX)
 303     if(n_lutexes > 0) {
 304         long offset;
 305         printf("writing %d lutexes to the core...\n", n_lutexes);
 306         write_lispobj(LUTEX_TABLE_CORE_ENTRY_TYPE_CODE, file);
 307         /* word count of the entry */
 308         write_lispobj(4, file);
 309         /* indicate how many lutexes we saved */
 310         write_lispobj(n_lutexes, file);
 311         /* save the lutexes */
 312         offset = write_bytes(file, (char *) lutex_addresses,
 313                              n_lutexes * sizeof(*lutex_addresses),
 314                              core_start_pos);
 315
 316         write_lispobj(offset, file);
 317     }
 318 #endif
 319
 320     write_lispobj(END_CORE_ENTRY_TYPE_CODE, file);
 321
 322     /* Write a trailing header, ignored when parsing the core normally.
 323      * This is used to locate the start of the core when the runtime is
 324      * prepended to it. */
 325     fseek(file, 0, SEEK_END);
 326     core_end_pos = ftell(file);
 327     core_size = core_end_pos - core_start_pos;
 328
 329     fwrite(&core_size, sizeof(os_vm_offset_t), 1, file);
 330     write_lispobj(CORE_MAGIC, file);
 331     fclose(file);
 332
 333 #ifndef LISP_FEATURE_WIN32
 334     if (make_executable)
 335         chmod (filename, 0755);
 336 #endif
 337
 338     printf("done]\n");
 339     exit(0);
 340 }
 341
 342 /* Slurp the executable portion of the runtime into a malloced buffer
 343  * and return it.  Places the size in bytes of the runtime into
 344  * 'size_out'.  Returns NULL if the runtime cannot be loaded from
 345  * 'runtime_path'. */
 346 void *
 347 load_runtime(char *runtime_path, size_t *size_out)
 348 {
 349     void *buf = NULL;
 350     FILE *input = NULL;
 351     size_t size, count;
 352     os_vm_offset_t core_offset;
 353
 354     core_offset = search_for_embedded_core (runtime_path);
 355     if ((input = fopen(runtime_path, "rb")) == NULL) {
 356         fprintf(stderr, "Unable to open runtime: %s\n", runtime_path);
 357         goto lose;
 358     }
 359
 360     fseek(input, 0, SEEK_END);
 361     size = (size_t) ftell(input);
 362     fseek(input, 0, SEEK_SET);
 363
 364     if (core_offset != -1 && size > core_offset)
 365         size = core_offset;
 366
 367     buf = successful_malloc(size);
 368     if ((count = fread(buf, 1, size, input)) != size) {
 369         fprintf(stderr, "Premature EOF while reading runtime.\n");
 370         goto lose;
 371     }
 372
 373     fclose(input);
 374     *size_out = size;
 375     return buf;
 376
 377 lose:
 378     if (input != NULL)
 379         fclose(input);
 380     if (buf != NULL)
 381         free(buf);
 382     return NULL;
 383 }
 384
 385 boolean
 386 save_runtime_to_filehandle(FILE *output, void *runtime, size_t runtime_size)
 387 {
 388     size_t padding;
 389     void *padbytes;
 390
 391     fwrite(runtime, 1, runtime_size, output);
 392
 393     padding = (os_vm_page_size - (runtime_size % os_vm_page_size)) & ~os_vm_page_size;
 394     if (padding > 0) {
 395         padbytes = successful_malloc(padding);
 396         memset(padbytes, 0, padding);
 397         fwrite(padbytes, 1, padding, output);
 398         free(padbytes);
 399     }
 400
 401     return 1;
 402 }
 403
 404 FILE *
 405 prepare_to_save(char *filename, boolean prepend_runtime, void **runtime_bytes,
 406                 size_t *runtime_size)
 407 {
 408     FILE *file;
 409     char *runtime_path;
 410
 411     if (prepend_runtime) {
 412         runtime_path = os_get_runtime_executable_path();
 413
 414         if (runtime_path == NULL) {
 415             fprintf(stderr, "Unable to get default runtime path.\n");
 416             return NULL;
 417         }
 418
 419         *runtime_bytes = load_runtime(runtime_path, runtime_size);
 420         free(runtime_path);
 421
 422         if (*runtime_bytes == NULL)
 423             return 0;
 424     }
 425
 426     file = open_core_for_saving(filename);
 427     if (file == NULL) {
 428         free(*runtime_bytes);
 429         perror(filename);
 430         return NULL;
 431     }
 432
 433     return file;
 434 }
 435
 436 boolean
 437 save(char *filename, lispobj init_function, boolean prepend_runtime)
 438 {
 439     FILE *file;
 440     void *runtime_bytes = NULL;
 441     size_t runtime_size;
 442
 443     file = prepare_to_save(filename, prepend_runtime, &runtime_bytes, &runtime_size);
 444     if (file == NULL)
 445         return 1;
 446
 447     if (prepend_runtime)
 448         save_runtime_to_filehandle(file, runtime_bytes, runtime_size);
 449
 450     return save_to_filehandle(file, filename, init_function, prepend_runtime);
 451 }