boehm-gc/misc.c

   1 /*
   2  * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
   3  * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
   4  *
   5  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
   6  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
   7  *
   8  * Permission is hereby granted to use or copy this program
   9  * for any purpose,  provided the above notices are retained on all copies.
  10  * Permission to modify the code and to distribute modified code is granted,
  11  * provided the above notices are retained, and a notice that the code was
  12  * modified is included with the above copyright notice.
  13  */
  14 /* Boehm, July 31, 1995 5:02 pm PDT */
  15
  16
  17 #include <stdio.h>
  18 #include <signal.h>
  19
  20 #define I_HIDE_POINTERS /* To make GC_call_with_alloc_lock visible */
  21 #include "gc_priv.h"
  22
  23 #ifdef SOLARIS_THREADS
  24 # include <sys/syscall.h>
  25 #endif
  26 #ifdef MSWIN32
  27 # include <windows.h>
  28 #endif
  29
  30 # ifdef THREADS
  31 #   ifdef PCR
  32 #     include "il/PCR_IL.h"
  33       PCR_Th_ML GC_allocate_ml;
  34 #   else
  35 #     ifdef SRC_M3
  36         /* Critical section counter is defined in the M3 runtime        */
  37         /* That's all we use.                                           */
  38 #     else
  39 #       ifdef SOLARIS_THREADS
  40           mutex_t GC_allocate_ml;       /* Implicitly initialized.      */
  41 #       else
  42 #          ifdef WIN32_THREADS
  43               GC_API CRITICAL_SECTION GC_allocate_ml;
  44 #          else
  45 #             if defined(IRIX_THREADS) || defined(IRIX_JDK_THREADS) \
  46                  || (defined(LINUX_THREADS) && defined(USE_SPIN_LOCK))
  47                 pthread_t GC_lock_holder = NO_THREAD;
  48 #             else
  49 #               if defined(HPUX_THREADS) \
  50                    || defined(LINUX_THREADS) && !defined(USE_SPIN_LOCK)
  51                   pthread_mutex_t GC_allocate_ml = PTHREAD_MUTEX_INITIALIZER;
  52 #               else
  53                   --> declare allocator lock here
  54 #               endif
  55 #             endif
  56 #          endif
  57 #       endif
  58 #     endif
  59 #   endif
  60 # endif
  61
  62 #ifdef ECOS
  63 #undef STACKBASE
  64 #endif
  65
  66 GC_FAR struct _GC_arrays GC_arrays /* = { 0 } */;
  67
  68
  69 GC_bool GC_debugging_started = FALSE;
  70         /* defined here so we don't have to load debug_malloc.o */
  71
  72 void (*GC_check_heap)() = (void (*)())0;
  73
  74 void (*GC_start_call_back)() = (void (*)())0;
  75
  76 ptr_t GC_stackbottom = 0;
  77
  78 GC_bool GC_dont_gc = 0;
  79
  80 GC_bool GC_quiet = 0;
  81
  82 #ifdef FIND_LEAK
  83   int GC_find_leak = 1;
  84 #else
  85   int GC_find_leak = 0;
  86 #endif
  87
  88 /*ARGSUSED*/
  89 GC_PTR GC_default_oom_fn GC_PROTO((size_t bytes_requested))
  90 {
  91     return(0);
  92 }
  93
  94 GC_PTR (*GC_oom_fn) GC_PROTO((size_t bytes_requested)) = GC_default_oom_fn;
  95
  96 extern signed_word GC_mem_found;
  97
  98 # ifdef MERGE_SIZES
  99     /* Set things up so that GC_size_map[i] >= words(i),                */
 100     /* but not too much bigger                                          */
 101     /* and so that size_map contains relatively few distinct entries    */
 102     /* This is stolen from Russ Atkinson's Cedar quantization           */
 103     /* alogrithm (but we precompute it).                                */
 104
 105
 106     void GC_init_size_map()
 107     {
 108         register unsigned i;
 109
 110         /* Map size 0 to something bigger.                         */
 111         /* This avoids problems at lower levels.                   */
 112         /* One word objects don't have to be 2 word aligned.       */
 113           for (i = 0; i < sizeof(word); i++) {
 114               GC_size_map[i] = MIN_WORDS;
 115           }
 116 #         if MIN_WORDS > 1
 117             GC_size_map[sizeof(word)] = MIN_WORDS;
 118 #         else
 119             GC_size_map[sizeof(word)] = ROUNDED_UP_WORDS(sizeof(word));
 120 #         endif
 121         for (i = sizeof(word) + 1; i <= 8 * sizeof(word); i++) {
 122 #           ifdef ALIGN_DOUBLE
 123               GC_size_map[i] = (ROUNDED_UP_WORDS(i) + 1) & (~1);
 124 #           else
 125               GC_size_map[i] = ROUNDED_UP_WORDS(i);
 126 #           endif
 127         }
 128         for (i = 8*sizeof(word) + 1; i <= 16 * sizeof(word); i++) {
 129               GC_size_map[i] = (ROUNDED_UP_WORDS(i) + 1) & (~1);
 130         }
 131 #       ifdef GC_GCJ_SUPPORT
 132            /* Make all sizes up to 32 words predictable, so that a      */
 133            /* compiler can statically perform the same computation,     */
 134            /* or at least a computation that results in similar size    */
 135            /* classes.                                                  */
 136            for (i = 16*sizeof(word) + 1; i <= 32 * sizeof(word); i++) {
 137               GC_size_map[i] = (ROUNDED_UP_WORDS(i) + 3) & (~3);
 138            }
 139 #       endif
 140         /* We leave the rest of the array to be filled in on demand. */
 141     }
 142
 143     /* Fill in additional entries in GC_size_map, including the ith one */
 144     /* We assume the ith entry is currently 0.                          */
 145     /* Note that a filled in section of the array ending at n always    */
 146     /* has length at least n/4.                                         */
 147     void GC_extend_size_map(i)
 148     word i;
 149     {
 150         word orig_word_sz = ROUNDED_UP_WORDS(i);
 151         word word_sz = orig_word_sz;
 152         register word byte_sz = WORDS_TO_BYTES(word_sz);
 153                                 /* The size we try to preserve.         */
 154                                 /* Close to to i, unless this would     */
 155                                 /* introduce too many distinct sizes.   */
 156         word smaller_than_i = byte_sz - (byte_sz >> 3);
 157         word much_smaller_than_i = byte_sz - (byte_sz >> 2);
 158         register word low_limit;        /* The lowest indexed entry we  */
 159                                         /* initialize.                  */
 160         register word j;
 161
 162         if (GC_size_map[smaller_than_i] == 0) {
 163             low_limit = much_smaller_than_i;
 164             while (GC_size_map[low_limit] != 0) low_limit++;
 165         } else {
 166             low_limit = smaller_than_i + 1;
 167             while (GC_size_map[low_limit] != 0) low_limit++;
 168             word_sz = ROUNDED_UP_WORDS(low_limit);
 169             word_sz += word_sz >> 3;
 170             if (word_sz < orig_word_sz) word_sz = orig_word_sz;
 171         }
 172 #       ifdef ALIGN_DOUBLE
 173             word_sz += 1;
 174             word_sz &= ~1;
 175 #       endif
 176         if (word_sz > MAXOBJSZ) {
 177             word_sz = MAXOBJSZ;
 178         }
 179         /* If we can fit the same number of larger objects in a block,  */
 180         /* do so.                                                       */
 181         {
 182             size_t number_of_objs = BODY_SZ/word_sz;
 183             word_sz = BODY_SZ/number_of_objs;
 184 #           ifdef ALIGN_DOUBLE
 185                 word_sz &= ~1;
 186 #           endif
 187         }
 188         byte_sz = WORDS_TO_BYTES(word_sz);
 189 #       ifdef ADD_BYTE_AT_END
 190             /* We need one extra byte; don't fill in GC_size_map[byte_sz] */
 191             byte_sz--;
 192 #       endif
 193
 194         for (j = low_limit; j <= byte_sz; j++) GC_size_map[j] = word_sz;
 195     }
 196 # endif
 197
 198
 199 /*
 200  * The following is a gross hack to deal with a problem that can occur
 201  * on machines that are sloppy about stack frame sizes, notably SPARC.
 202  * Bogus pointers may be written to the stack and not cleared for
 203  * a LONG time, because they always fall into holes in stack frames
 204  * that are not written.  We partially address this by clearing
 205  * sections of the stack whenever we get control.
 206  */
 207 word GC_stack_last_cleared = 0; /* GC_no when we last did this */
 208 # ifdef THREADS
 209 #   define CLEAR_SIZE 512
 210 # else
 211 #   define CLEAR_SIZE 213
 212 # endif
 213 # define DEGRADE_RATE 50
 214
 215 word GC_min_sp;         /* Coolest stack pointer value from which we've */
 216                         /* already cleared the stack.                   */
 217
 218 # ifdef STACK_GROWS_DOWN
 219 #   define COOLER_THAN >
 220 #   define HOTTER_THAN <
 221 #   define MAKE_COOLER(x,y) if ((word)(x)+(y) > (word)(x)) {(x) += (y);} \
 222                             else {(x) = (word)ONES;}
 223 #   define MAKE_HOTTER(x,y) (x) -= (y)
 224 # else
 225 #   define COOLER_THAN <
 226 #   define HOTTER_THAN >
 227 #   define MAKE_COOLER(x,y) if ((word)(x)-(y) < (word)(x)) {(x) -= (y);} else {(x) = 0;}
 228 #   define MAKE_HOTTER(x,y) (x) += (y)
 229 # endif
 230
 231 word GC_high_water;
 232                         /* "hottest" stack pointer value we have seen   */
 233                         /* recently.  Degrades over time.               */
 234
 235 word GC_words_allocd_at_reset;
 236
 237 #if defined(ASM_CLEAR_CODE) && !defined(THREADS)
 238   extern ptr_t GC_clear_stack_inner();
 239 #endif
 240
 241 #if !defined(ASM_CLEAR_CODE) && !defined(THREADS)
 242 /* Clear the stack up to about limit.  Return arg. */
 243 /*ARGSUSED*/
 244 ptr_t GC_clear_stack_inner(arg, limit)
 245 ptr_t arg;
 246 word limit;
 247 {
 248     word dummy[CLEAR_SIZE];
 249
 250     BZERO(dummy, CLEAR_SIZE*sizeof(word));
 251     if ((word)(dummy) COOLER_THAN limit) {
 252         (void) GC_clear_stack_inner(arg, limit);
 253     }
 254     /* Make sure the recursive call is not a tail call, and the bzero   */
 255     /* call is not recognized as dead code.                             */
 256     GC_noop1((word)dummy);
 257     return(arg);
 258 }
 259 #endif
 260
 261 /* Clear some of the inaccessible part of the stack.  Returns its       */
 262 /* argument, so it can be used in a tail call position, hence clearing  */
 263 /* another frame.                                                       */
 264 ptr_t GC_clear_stack(arg)
 265 ptr_t arg;
 266 {
 267     register word sp = (word)GC_approx_sp();  /* Hotter than actual sp */
 268 #   ifdef THREADS
 269         word dummy[CLEAR_SIZE];
 270 #   else
 271         register word limit;
 272 #   endif
 273
 274 #   define SLOP 400
 275         /* Extra bytes we clear every time.  This clears our own        */
 276         /* activation record, and should cause more frequent            */
 277         /* clearing near the cold end of the stack, a good thing.       */
 278 #   define GC_SLOP 4000
 279         /* We make GC_high_water this much hotter than we really saw    */
 280         /* saw it, to cover for GC noise etc. above our current frame.  */
 281 #   define CLEAR_THRESHOLD 100000
 282         /* We restart the clearing process after this many bytes of     */
 283         /* allocation.  Otherwise very heavily recursive programs       */
 284         /* with sparse stacks may result in heaps that grow almost      */
 285         /* without bounds.  As the heap gets larger, collection         */
 286         /* frequency decreases, thus clearing frequency would decrease, */
 287         /* thus more junk remains accessible, thus the heap gets        */
 288         /* larger ...                                                   */
 289 # ifdef THREADS
 290     BZERO(dummy, CLEAR_SIZE*sizeof(word));
 291 # else
 292     if (GC_gc_no > GC_stack_last_cleared) {
 293         /* Start things over, so we clear the entire stack again */
 294         if (GC_stack_last_cleared == 0) GC_high_water = (word) GC_stackbottom;
 295         GC_min_sp = GC_high_water;
 296         GC_stack_last_cleared = GC_gc_no;
 297         GC_words_allocd_at_reset = GC_words_allocd;
 298     }
 299     /* Adjust GC_high_water */
 300         MAKE_COOLER(GC_high_water, WORDS_TO_BYTES(DEGRADE_RATE) + GC_SLOP);
 301         if (sp HOTTER_THAN GC_high_water) {
 302             GC_high_water = sp;
 303         }
 304         MAKE_HOTTER(GC_high_water, GC_SLOP);
 305     limit = GC_min_sp;
 306     MAKE_HOTTER(limit, SLOP);
 307     if (sp COOLER_THAN limit) {
 308         limit &= ~0xf;  /* Make it sufficiently aligned for assembly    */
 309                         /* implementations of GC_clear_stack_inner.     */
 310         GC_min_sp = sp;
 311         return(GC_clear_stack_inner(arg, limit));
 312     } else if (WORDS_TO_BYTES(GC_words_allocd - GC_words_allocd_at_reset)
 313                > CLEAR_THRESHOLD) {
 314         /* Restart clearing process, but limit how much clearing we do. */
 315         GC_min_sp = sp;
 316         MAKE_HOTTER(GC_min_sp, CLEAR_THRESHOLD/4);
 317         if (GC_min_sp HOTTER_THAN GC_high_water) GC_min_sp = GC_high_water;
 318         GC_words_allocd_at_reset = GC_words_allocd;
 319     }
 320 # endif
 321   return(arg);
 322 }
 323
 324
 325 /* Return a pointer to the base address of p, given a pointer to a      */
 326 /* an address within an object.  Return 0 o.w.                          */
 327 # ifdef __STDC__
 328     GC_PTR GC_base(GC_PTR p)
 329 # else
 330     GC_PTR GC_base(p)
 331     GC_PTR p;
 332 # endif
 333 {
 334     register word r;
 335     register struct hblk *h;
 336     register bottom_index *bi;
 337     register hdr *candidate_hdr;
 338     register word limit;
 339
 340     r = (word)p;
 341     if (!GC_is_initialized) return 0;
 342     h = HBLKPTR(r);
 343     GET_BI(r, bi);
 344     candidate_hdr = HDR_FROM_BI(bi, r);
 345     if (candidate_hdr == 0) return(0);
 346     /* If it's a pointer to the middle of a large object, move it       */
 347     /* to the beginning.                                                */
 348         while (IS_FORWARDING_ADDR_OR_NIL(candidate_hdr)) {
 349            h = FORWARDED_ADDR(h,candidate_hdr);
 350            r = (word)h + HDR_BYTES;
 351            candidate_hdr = HDR(h);
 352         }
 353     if (candidate_hdr -> hb_map == GC_invalid_map) return(0);
 354     /* Make sure r points to the beginning of the object */
 355         r &= ~(WORDS_TO_BYTES(1) - 1);
 356         {
 357             register int offset = (char *)r - (char *)(HBLKPTR(r));
 358             register signed_word sz = candidate_hdr -> hb_sz;
 359
 360 #           ifdef ALL_INTERIOR_POINTERS
 361               register map_entry_type map_entry;
 362
 363               map_entry = MAP_ENTRY((candidate_hdr -> hb_map), offset);
 364               if (map_entry == OBJ_INVALID) {
 365                 return(0);
 366               }
 367               r -= WORDS_TO_BYTES(map_entry);
 368               limit = r + WORDS_TO_BYTES(sz);
 369 #           else
 370               register int correction;
 371
 372               offset = BYTES_TO_WORDS(offset - HDR_BYTES);
 373               correction = offset % sz;
 374               r -= (WORDS_TO_BYTES(correction));
 375               limit = r + WORDS_TO_BYTES(sz);
 376               if (limit > (word)(h + 1)
 377                 && sz <= BYTES_TO_WORDS(HBLKSIZE) - HDR_WORDS) {
 378                 return(0);
 379               }
 380 #           endif
 381             if ((word)p >= limit) return(0);
 382         }
 383     return((GC_PTR)r);
 384 }
 385
 386
 387 /* Return the size of an object, given a pointer to its base.           */
 388 /* (For small obects this also happens to work from interior pointers,  */
 389 /* but that shouldn't be relied upon.)                                  */
 390 # ifdef __STDC__
 391     size_t GC_size(GC_PTR p)
 392 # else
 393     size_t GC_size(p)
 394     GC_PTR p;
 395 # endif
 396 {
 397     register int sz;
 398     register hdr * hhdr = HDR(p);
 399
 400     sz = WORDS_TO_BYTES(hhdr -> hb_sz);
 401     if (sz < 0) {
 402         return(-sz);
 403     } else {
 404         return(sz);
 405     }
 406 }
 407
 408 size_t GC_get_heap_size GC_PROTO(())
 409 {
 410     return ((size_t) GC_heapsize);
 411 }
 412
 413 size_t GC_get_free_bytes GC_PROTO(())
 414 {
 415     return ((size_t) GC_large_free_bytes);
 416 }
 417
 418 size_t GC_get_bytes_since_gc GC_PROTO(())
 419 {
 420     return ((size_t) WORDS_TO_BYTES(GC_words_allocd));
 421 }
 422
 423 GC_bool GC_is_initialized = FALSE;
 424
 425 void GC_init()
 426 {
 427     DCL_LOCK_STATE;
 428
 429     DISABLE_SIGNALS();
 430     LOCK();
 431     GC_init_inner();
 432     UNLOCK();
 433     ENABLE_SIGNALS();
 434
 435 }
 436
 437 #ifdef MSWIN32
 438     extern void GC_init_win32();
 439 #endif
 440
 441 extern void GC_setpagesize();
 442
 443 void GC_init_inner()
 444 {
 445 #   ifndef THREADS
 446         word dummy;
 447 #   endif
 448
 449     if (GC_is_initialized) return;
 450     GC_setpagesize();
 451     GC_exclude_static_roots(beginGC_arrays, end_gc_area);
 452 #   ifdef PRINTSTATS
 453         if ((ptr_t)endGC_arrays != (ptr_t)(&GC_obj_kinds)) {
 454             GC_printf0("Reordering linker, didn't exclude obj_kinds\n");
 455         }
 456 #   endif
 457 #   ifdef MSWIN32
 458         GC_init_win32();
 459 #   endif
 460 #   if defined(SEARCH_FOR_DATA_START)
 461         /* This doesn't really work if the collector is in a shared library. */
 462         GC_init_linux_data_start();
 463 #   endif
 464 #   ifdef SOLARIS_THREADS
 465         GC_thr_init();
 466         /* We need dirty bits in order to find live stack sections.     */
 467         GC_dirty_init();
 468 #   endif
 469 #   if defined(IRIX_THREADS) || defined(LINUX_THREADS) \
 470        || defined(IRIX_JDK_THREADS) || defined(HPUX_THREADS)
 471         GC_thr_init();
 472 #   endif
 473 #   if !defined(THREADS) || defined(SOLARIS_THREADS) || defined(WIN32_THREADS) \
 474        || defined(IRIX_THREADS) || defined(LINUX_THREADS) \
 475        || defined(HPUX_THREADS)
 476       if (GC_stackbottom == 0) {
 477         GC_stackbottom = GC_get_stack_base();
 478       }
 479 #   endif
 480     if  (sizeof (ptr_t) != sizeof(word)) {
 481         ABORT("sizeof (ptr_t) != sizeof(word)\n");
 482     }
 483     if  (sizeof (signed_word) != sizeof(word)) {
 484         ABORT("sizeof (signed_word) != sizeof(word)\n");
 485     }
 486     if  (sizeof (struct hblk) != HBLKSIZE) {
 487         ABORT("sizeof (struct hblk) != HBLKSIZE\n");
 488     }
 489 #   ifndef THREADS
 490 #     if defined(STACK_GROWS_UP) && defined(STACK_GROWS_DOWN)
 491         ABORT(
 492           "Only one of STACK_GROWS_UP and STACK_GROWS_DOWN should be defd\n");
 493 #     endif
 494 #     if !defined(STACK_GROWS_UP) && !defined(STACK_GROWS_DOWN)
 495         ABORT(
 496           "One of STACK_GROWS_UP and STACK_GROWS_DOWN should be defd\n");
 497 #     endif
 498 #     ifdef STACK_GROWS_DOWN
 499         if ((word)(&dummy) > (word)GC_stackbottom) {
 500           GC_err_printf0(
 501                 "STACK_GROWS_DOWN is defd, but stack appears to grow up\n");
 502 #         ifndef UTS4  /* Compiler bug workaround */
 503             GC_err_printf2("sp = 0x%lx, GC_stackbottom = 0x%lx\n",
 504                            (unsigned long) (&dummy),
 505                            (unsigned long) GC_stackbottom);
 506 #         endif
 507           ABORT("stack direction 3\n");
 508         }
 509 #     else
 510         if ((word)(&dummy) < (word)GC_stackbottom) {
 511           GC_err_printf0(
 512                 "STACK_GROWS_UP is defd, but stack appears to grow down\n");
 513           GC_err_printf2("sp = 0x%lx, GC_stackbottom = 0x%lx\n",
 514                          (unsigned long) (&dummy),
 515                          (unsigned long) GC_stackbottom);
 516           ABORT("stack direction 4");
 517         }
 518 #     endif
 519 #   endif
 520 #   if !defined(_AUX_SOURCE) || defined(__GNUC__)
 521       if ((word)(-1) < (word)0) {
 522         GC_err_printf0("The type word should be an unsigned integer type\n");
 523         GC_err_printf0("It appears to be signed\n");
 524         ABORT("word");
 525       }
 526 #   endif
 527     if ((signed_word)(-1) >= (signed_word)0) {
 528         GC_err_printf0(
 529                 "The type signed_word should be a signed integer type\n");
 530         GC_err_printf0("It appears to be unsigned\n");
 531         ABORT("signed_word");
 532     }
 533
 534     /* Add initial guess of root sets.  Do this first, since sbrk(0)    */
 535     /* might be used.                                                   */
 536       GC_register_data_segments();
 537     GC_init_headers();
 538     GC_bl_init();
 539     GC_mark_init();
 540     if (!GC_expand_hp_inner((word)MINHINCR)) {
 541         GC_err_printf0("Can't start up: not enough memory\n");
 542         EXIT();
 543     }
 544     /* Preallocate large object map.  It's otherwise inconvenient to    */
 545     /* deal with failure.                                               */
 546       if (!GC_add_map_entry((word)0)) {
 547         GC_err_printf0("Can't start up: not enough memory\n");
 548         EXIT();
 549       }
 550     GC_register_displacement_inner(0L);
 551 #   ifdef MERGE_SIZES
 552       GC_init_size_map();
 553 #   endif
 554 #   ifdef PCR
 555       if (PCR_IL_Lock(PCR_Bool_false, PCR_allSigsBlocked, PCR_waitForever)
 556           != PCR_ERes_okay) {
 557           ABORT("Can't lock load state\n");
 558       } else if (PCR_IL_Unlock() != PCR_ERes_okay) {
 559           ABORT("Can't unlock load state\n");
 560       }
 561       PCR_IL_Unlock();
 562       GC_pcr_install();
 563 #   endif
 564     /* Get black list set up */
 565       GC_gcollect_inner();
 566 #   ifdef STUBBORN_ALLOC
 567         GC_stubborn_init();
 568 #   endif
 569     GC_is_initialized = TRUE;
 570     /* Convince lint that some things are used */
 571 #   ifdef LINT
 572       {
 573           extern char * GC_copyright[];
 574           extern int GC_read();
 575           extern void GC_register_finalizer_no_order();
 576
 577           GC_noop(GC_copyright, GC_find_header,
 578                   GC_push_one, GC_call_with_alloc_lock, GC_read,
 579                   GC_dont_expand,
 580 #                 ifndef NO_DEBUGGING
 581                     GC_dump,
 582 #                 endif
 583                   GC_register_finalizer_no_order);
 584       }
 585 #   endif
 586 }
 587
 588 void GC_enable_incremental GC_PROTO(())
 589 {
 590 # if !defined(SMALL_CONFIG)
 591   if (!GC_find_leak) {
 592     DCL_LOCK_STATE;
 593
 594     DISABLE_SIGNALS();
 595     LOCK();
 596     if (GC_incremental) goto out;
 597     GC_setpagesize();
 598 #   ifdef MSWIN32
 599       {
 600         extern GC_bool GC_is_win32s();
 601
 602         /* VirtualProtect is not functional under win32s.       */
 603         if (GC_is_win32s()) goto out;
 604       }
 605 #   endif /* MSWIN32 */
 606 #   ifndef SOLARIS_THREADS
 607         GC_dirty_init();
 608 #   endif
 609     if (!GC_is_initialized) {
 610         GC_init_inner();
 611     }
 612     if (GC_dont_gc) {
 613         /* Can't easily do it. */
 614         UNLOCK();
 615         ENABLE_SIGNALS();
 616         return;
 617     }
 618     if (GC_words_allocd > 0) {
 619         /* There may be unmarked reachable objects      */
 620         GC_gcollect_inner();
 621     }   /* else we're OK in assuming everything's       */
 622         /* clean since nothing can point to an          */
 623         /* unmarked object.                             */
 624     GC_read_dirty();
 625     GC_incremental = TRUE;
 626 out:
 627     UNLOCK();
 628     ENABLE_SIGNALS();
 629   }
 630 # endif
 631 }
 632
 633
 634 #ifdef MSWIN32
 635 # define LOG_FILE "gc.log"
 636
 637   HANDLE GC_stdout = 0, GC_stderr;
 638   int GC_tmp;
 639   DWORD GC_junk;
 640
 641   void GC_set_files()
 642   {
 643     if (!GC_stdout) {
 644         GC_stdout = CreateFile(LOG_FILE, GENERIC_WRITE,
 645                                FILE_SHARE_READ | FILE_SHARE_WRITE,
 646                                NULL, CREATE_ALWAYS, FILE_FLAG_WRITE_THROUGH,
 647                                NULL);
 648         if (INVALID_HANDLE_VALUE == GC_stdout) ABORT("Open of log file failed");
 649     }
 650     if (GC_stderr == 0) {
 651         GC_stderr = GC_stdout;
 652     }
 653   }
 654
 655 #endif
 656
 657 #if defined(OS2) || defined(MACOS)
 658 FILE * GC_stdout = NULL;
 659 FILE * GC_stderr = NULL;
 660 int GC_tmp;  /* Should really be local ... */
 661
 662   void GC_set_files()
 663   {
 664       if (GC_stdout == NULL) {
 665         GC_stdout = stdout;
 666     }
 667     if (GC_stderr == NULL) {
 668         GC_stderr = stderr;
 669     }
 670   }
 671 #endif
 672
 673 #if !defined(OS2) && !defined(MACOS) && !defined(MSWIN32)
 674   int GC_stdout = 1;
 675   int GC_stderr = 2;
 676 # if !defined(AMIGA)
 677 #   include <unistd.h>
 678 # endif
 679 #endif
 680
 681 #if !defined(MSWIN32)  && !defined(OS2) && !defined(MACOS) && !defined(ECOS)
 682 int GC_write(fd, buf, len)
 683 int fd;
 684 char *buf;
 685 size_t len;
 686 {
 687      register int bytes_written = 0;
 688      register int result;
 689
 690      while (bytes_written < len) {
 691 #       ifdef SOLARIS_THREADS
 692             result = syscall(SYS_write, fd, buf + bytes_written,
 693                                             len - bytes_written);
 694 #       else
 695             result = write(fd, buf + bytes_written, len - bytes_written);
 696 #       endif
 697         if (-1 == result) return(result);
 698         bytes_written += result;
 699     }
 700     return(bytes_written);
 701 }
 702 #endif /* UN*X */
 703
 704 #if defined(ECOS)
 705 int GC_write(fd, buf, len)
 706 {
 707   _Jv_diag_write (buf, len);
 708   return len;
 709 }
 710 #endif
 711
 712
 713 #ifdef MSWIN32
 714 #   define WRITE(f, buf, len) (GC_set_files(), \
 715                                GC_tmp = WriteFile((f), (buf), \
 716                                                   (len), &GC_junk, NULL),\
 717                                (GC_tmp? 1 : -1))
 718 #else
 719 #   if defined(OS2) || defined(MACOS)
 720 #   define WRITE(f, buf, len) (GC_set_files(), \
 721                                GC_tmp = fwrite((buf), 1, (len), (f)), \
 722                                fflush(f), GC_tmp)
 723 #   else
 724 #     define WRITE(f, buf, len) GC_write((f), (buf), (len))
 725 #   endif
 726 #endif
 727
 728 /* A version of printf that is unlikely to call malloc, and is thus safer */
 729 /* to call from the collector in case malloc has been bound to GC_malloc. */
 730 /* Assumes that no more than 1023 characters are written at once.         */
 731 /* Assumes that all arguments have been converted to something of the     */
 732 /* same size as long, and that the format conversions expect something    */
 733 /* of that size.                                                          */
 734 void GC_printf(format, a, b, c, d, e, f)
 735 char * format;
 736 long a, b, c, d, e, f;
 737 {
 738     char buf[1025];
 739
 740     if (GC_quiet) return;
 741     buf[1024] = 0x15;
 742     (void) sprintf(buf, format, a, b, c, d, e, f);
 743     if (buf[1024] != 0x15) ABORT("GC_printf clobbered stack");
 744     if (WRITE(GC_stdout, buf, strlen(buf)) < 0) ABORT("write to stdout failed");
 745 }
 746
 747 void GC_err_printf(format, a, b, c, d, e, f)
 748 char * format;
 749 long a, b, c, d, e, f;
 750 {
 751     char buf[1025];
 752
 753     buf[1024] = 0x15;
 754     (void) sprintf(buf, format, a, b, c, d, e, f);
 755     if (buf[1024] != 0x15) ABORT("GC_err_printf clobbered stack");
 756     if (WRITE(GC_stderr, buf, strlen(buf)) < 0) ABORT("write to stderr failed");
 757 }
 758
 759 void GC_err_puts(s)
 760 char *s;
 761 {
 762     if (WRITE(GC_stderr, s, strlen(s)) < 0) ABORT("write to stderr failed");
 763 }
 764
 765 # if defined(__STDC__) || defined(__cplusplus)
 766     void GC_default_warn_proc(char *msg, GC_word arg)
 767 # else
 768     void GC_default_warn_proc(msg, arg)
 769     char *msg;
 770     GC_word arg;
 771 # endif
 772 {
 773     GC_err_printf1(msg, (unsigned long)arg);
 774 }
 775
 776 GC_warn_proc GC_current_warn_proc = GC_default_warn_proc;
 777
 778 # if defined(__STDC__) || defined(__cplusplus)
 779     GC_warn_proc GC_set_warn_proc(GC_warn_proc p)
 780 # else
 781     GC_warn_proc GC_set_warn_proc(p)
 782     GC_warn_proc p;
 783 # endif
 784 {
 785     GC_warn_proc result;
 786
 787     LOCK();
 788     result = GC_current_warn_proc;
 789     GC_current_warn_proc = p;
 790     UNLOCK();
 791     return(result);
 792 }
 793
 794
 795 #ifndef PCR
 796 void GC_abort(msg)
 797 char * msg;
 798 {
 799     GC_err_printf1("%s\n", msg);
 800     (void) abort();
 801 }
 802 #endif
 803
 804 #ifdef NEED_CALLINFO
 805
 806 void GC_print_callers (info)
 807 struct callinfo info[NFRAMES];
 808 {
 809     register int i;
 810
 811 #   if NFRAMES == 1
 812       GC_err_printf0("\tCaller at allocation:\n");
 813 #   else
 814       GC_err_printf0("\tCall chain at allocation:\n");
 815 #   endif
 816     for (i = 0; i < NFRAMES; i++) {
 817         if (info[i].ci_pc == 0) break;
 818 #       if NARGS > 0
 819         {
 820           int j;
 821
 822           GC_err_printf0("\t\targs: ");
 823           for (j = 0; j < NARGS; j++) {
 824             if (j != 0) GC_err_printf0(", ");
 825             GC_err_printf2("%d (0x%X)", ~(info[i].ci_arg[j]),
 826                                         ~(info[i].ci_arg[j]));
 827           }
 828           GC_err_printf0("\n");
 829         }
 830 #       endif
 831         GC_err_printf1("\t\t##PC##= 0x%X\n", info[i].ci_pc);
 832     }
 833 }
 834
 835 #endif /* SAVE_CALL_CHAIN */
 836
 837 /* Needed by SRC_M3, gcj, and should perhaps be the official interface  */
 838 /* to GC_dont_gc.                                                       */
 839 void GC_enable()
 840 {
 841     GC_dont_gc--;
 842 }
 843
 844 void GC_disable()
 845 {
 846     GC_dont_gc++;
 847 }
 848
 849 #if !defined(NO_DEBUGGING)
 850
 851 void GC_dump()
 852 {
 853     GC_printf0("***Static roots:\n");
 854     GC_print_static_roots();
 855     GC_printf0("\n***Heap sections:\n");
 856     GC_print_heap_sects();
 857     GC_printf0("\n***Free blocks:\n");
 858     GC_print_hblkfreelist();
 859     GC_printf0("\n***Blocks in use:\n");
 860     GC_print_block_list();
 861 }
 862
 863 # endif /* NO_DEBUGGING */