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(LINUX_THREADS)
  46 #               ifdef UNDEFINED
  47                     pthread_mutex_t GC_allocate_ml = PTHREAD_MUTEX_INITIALIZER;
  48 #               endif
  49                 pthread_t GC_lock_holder = NO_THREAD;
  50 #             else
  51 #               if defined(QUICK_THREADS)
  52                     /* Nothing.  */
  53 #               else
  54                     --> declare allocator lock here
  55 #               endif
  56 #             endif
  57 #          endif
  58 #       endif
  59 #     endif
  60 #   endif
  61 # endif
  62
  63 #ifdef ECOS
  64 #undef STACKBASE
  65 #endif
  66
  67 GC_FAR struct _GC_arrays GC_arrays /* = { 0 } */;
  68
  69
  70 GC_bool GC_debugging_started = FALSE;
  71         /* defined here so we don't have to load debug_malloc.o */
  72
  73 void (*GC_check_heap)() = (void (*)())0;
  74
  75 void (*GC_start_call_back)() = (void (*)())0;
  76
  77 ptr_t GC_stackbottom = 0;
  78
  79 GC_bool GC_dont_gc = 0;
  80
  81 GC_bool GC_quiet = 0;
  82
  83 /*ARGSUSED*/
  84 GC_PTR GC_default_oom_fn GC_PROTO((size_t bytes_requested))
  85 {
  86     return(0);
  87 }
  88
  89 GC_PTR (*GC_oom_fn) GC_PROTO((size_t bytes_requested)) = GC_default_oom_fn;
  90
  91 extern signed_word GC_mem_found;
  92
  93 # ifdef MERGE_SIZES
  94     /* Set things up so that GC_size_map[i] >= words(i),                */
  95     /* but not too much bigger                                          */
  96     /* and so that size_map contains relatively few distinct entries    */
  97     /* This is stolen from Russ Atkinson's Cedar quantization           */
  98     /* alogrithm (but we precompute it).                                */
  99
 100
 101     void GC_init_size_map()
 102     {
 103         register unsigned i;
 104
 105         /* Map size 0 to 1.  This avoids problems at lower levels. */
 106           GC_size_map[0] = 1;
 107         /* One word objects don't have to be 2 word aligned.       */
 108           for (i = 1; i < sizeof(word); i++) {
 109               GC_size_map[i] = 1;
 110           }
 111           GC_size_map[sizeof(word)] = ROUNDED_UP_WORDS(sizeof(word));
 112         for (i = sizeof(word) + 1; i <= 8 * sizeof(word); i++) {
 113 #           ifdef ALIGN_DOUBLE
 114               GC_size_map[i] = (ROUNDED_UP_WORDS(i) + 1) & (~1);
 115 #           else
 116               GC_size_map[i] = ROUNDED_UP_WORDS(i);
 117 #           endif
 118         }
 119         for (i = 8*sizeof(word) + 1; i <= 16 * sizeof(word); i++) {
 120               GC_size_map[i] = (ROUNDED_UP_WORDS(i) + 1) & (~1);
 121         }
 122         /* We leave the rest of the array to be filled in on demand. */
 123     }
 124
 125     /* Fill in additional entries in GC_size_map, including the ith one */
 126     /* We assume the ith entry is currently 0.                          */
 127     /* Note that a filled in section of the array ending at n always    */
 128     /* has length at least n/4.                                         */
 129     void GC_extend_size_map(i)
 130     word i;
 131     {
 132         word orig_word_sz = ROUNDED_UP_WORDS(i);
 133         word word_sz = orig_word_sz;
 134         register word byte_sz = WORDS_TO_BYTES(word_sz);
 135                                 /* The size we try to preserve.         */
 136                                 /* Close to to i, unless this would     */
 137                                 /* introduce too many distinct sizes.   */
 138         word smaller_than_i = byte_sz - (byte_sz >> 3);
 139         word much_smaller_than_i = byte_sz - (byte_sz >> 2);
 140         register word low_limit;        /* The lowest indexed entry we  */
 141                                         /* initialize.                  */
 142         register word j;
 143
 144         if (GC_size_map[smaller_than_i] == 0) {
 145             low_limit = much_smaller_than_i;
 146             while (GC_size_map[low_limit] != 0) low_limit++;
 147         } else {
 148             low_limit = smaller_than_i + 1;
 149             while (GC_size_map[low_limit] != 0) low_limit++;
 150             word_sz = ROUNDED_UP_WORDS(low_limit);
 151             word_sz += word_sz >> 3;
 152             if (word_sz < orig_word_sz) word_sz = orig_word_sz;
 153         }
 154 #       ifdef ALIGN_DOUBLE
 155             word_sz += 1;
 156             word_sz &= ~1;
 157 #       endif
 158         if (word_sz > MAXOBJSZ) {
 159             word_sz = MAXOBJSZ;
 160         }
 161         /* If we can fit the same number of larger objects in a block,  */
 162         /* do so.                                                       */
 163         {
 164             size_t number_of_objs = BODY_SZ/word_sz;
 165             word_sz = BODY_SZ/number_of_objs;
 166 #           ifdef ALIGN_DOUBLE
 167                 word_sz &= ~1;
 168 #           endif
 169         }
 170         byte_sz = WORDS_TO_BYTES(word_sz);
 171 #       ifdef ADD_BYTE_AT_END
 172             /* We need one extra byte; don't fill in GC_size_map[byte_sz] */
 173             byte_sz--;
 174 #       endif
 175
 176         for (j = low_limit; j <= byte_sz; j++) GC_size_map[j] = word_sz;
 177     }
 178 # endif
 179
 180
 181 /*
 182  * The following is a gross hack to deal with a problem that can occur
 183  * on machines that are sloppy about stack frame sizes, notably SPARC.
 184  * Bogus pointers may be written to the stack and not cleared for
 185  * a LONG time, because they always fall into holes in stack frames
 186  * that are not written.  We partially address this by clearing
 187  * sections of the stack whenever we get control.
 188  */
 189 word GC_stack_last_cleared = 0; /* GC_no when we last did this */
 190 # ifdef THREADS
 191 #   define CLEAR_SIZE 2048
 192 # else
 193 #   define CLEAR_SIZE 213
 194 # endif
 195 # define DEGRADE_RATE 50
 196
 197 word GC_min_sp;         /* Coolest stack pointer value from which we've */
 198                         /* already cleared the stack.                   */
 199
 200 # ifdef STACK_GROWS_DOWN
 201 #   define COOLER_THAN >
 202 #   define HOTTER_THAN <
 203 #   define MAKE_COOLER(x,y) if ((word)(x)+(y) > (word)(x)) {(x) += (y);} \
 204                             else {(x) = (word)ONES;}
 205 #   define MAKE_HOTTER(x,y) (x) -= (y)
 206 # else
 207 #   define COOLER_THAN <
 208 #   define HOTTER_THAN >
 209 #   define MAKE_COOLER(x,y) if ((word)(x)-(y) < (word)(x)) {(x) -= (y);} else {(x) = 0;}
 210 #   define MAKE_HOTTER(x,y) (x) += (y)
 211 # endif
 212
 213 word GC_high_water;
 214                         /* "hottest" stack pointer value we have seen   */
 215                         /* recently.  Degrades over time.               */
 216
 217 word GC_words_allocd_at_reset;
 218
 219 #if defined(ASM_CLEAR_CODE) && !defined(THREADS)
 220   extern ptr_t GC_clear_stack_inner();
 221 #endif
 222
 223 #if !defined(ASM_CLEAR_CODE) && !defined(THREADS)
 224 /* Clear the stack up to about limit.  Return arg. */
 225 /*ARGSUSED*/
 226 ptr_t GC_clear_stack_inner(arg, limit)
 227 ptr_t arg;
 228 word limit;
 229 {
 230     word dummy[CLEAR_SIZE];
 231
 232     BZERO(dummy, CLEAR_SIZE*sizeof(word));
 233     if ((word)(dummy) COOLER_THAN limit) {
 234         (void) GC_clear_stack_inner(arg, limit);
 235     }
 236     /* Make sure the recursive call is not a tail call, and the bzero   */
 237     /* call is not recognized as dead code.                             */
 238     GC_noop1((word)dummy);
 239     return(arg);
 240 }
 241 #endif
 242
 243 /* Clear some of the inaccessible part of the stack.  Returns its       */
 244 /* argument, so it can be used in a tail call position, hence clearing  */
 245 /* another frame.                                                       */
 246 ptr_t GC_clear_stack(arg)
 247 ptr_t arg;
 248 {
 249     register word sp = (word)GC_approx_sp();  /* Hotter than actual sp */
 250 #   ifdef THREADS
 251         word dummy[CLEAR_SIZE];
 252 #   else
 253         register word limit;
 254 #   endif
 255
 256 #   define SLOP 400
 257         /* Extra bytes we clear every time.  This clears our own        */
 258         /* activation record, and should cause more frequent            */
 259         /* clearing near the cold end of the stack, a good thing.       */
 260 #   define GC_SLOP 4000
 261         /* We make GC_high_water this much hotter than we really saw    */
 262         /* saw it, to cover for GC noise etc. above our current frame.  */
 263 #   define CLEAR_THRESHOLD 100000
 264         /* We restart the clearing process after this many bytes of     */
 265         /* allocation.  Otherwise very heavily recursive programs       */
 266         /* with sparse stacks may result in heaps that grow almost      */
 267         /* without bounds.  As the heap gets larger, collection         */
 268         /* frequency decreases, thus clearing frequency would decrease, */
 269         /* thus more junk remains accessible, thus the heap gets        */
 270         /* larger ...                                                   */
 271 # ifdef THREADS
 272     BZERO(dummy, CLEAR_SIZE*sizeof(word));
 273 # else
 274     if (GC_gc_no > GC_stack_last_cleared) {
 275         /* Start things over, so we clear the entire stack again */
 276         if (GC_stack_last_cleared == 0) GC_high_water = (word) GC_stackbottom;
 277         GC_min_sp = GC_high_water;
 278         GC_stack_last_cleared = GC_gc_no;
 279         GC_words_allocd_at_reset = GC_words_allocd;
 280     }
 281     /* Adjust GC_high_water */
 282         MAKE_COOLER(GC_high_water, WORDS_TO_BYTES(DEGRADE_RATE) + GC_SLOP);
 283         if (sp HOTTER_THAN GC_high_water) {
 284             GC_high_water = sp;
 285         }
 286         MAKE_HOTTER(GC_high_water, GC_SLOP);
 287     limit = GC_min_sp;
 288     MAKE_HOTTER(limit, SLOP);
 289     if (sp COOLER_THAN limit) {
 290         limit &= ~0xf;  /* Make it sufficiently aligned for assembly    */
 291                         /* implementations of GC_clear_stack_inner.     */
 292         GC_min_sp = sp;
 293         return(GC_clear_stack_inner(arg, limit));
 294     } else if (WORDS_TO_BYTES(GC_words_allocd - GC_words_allocd_at_reset)
 295                > CLEAR_THRESHOLD) {
 296         /* Restart clearing process, but limit how much clearing we do. */
 297         GC_min_sp = sp;
 298         MAKE_HOTTER(GC_min_sp, CLEAR_THRESHOLD/4);
 299         if (GC_min_sp HOTTER_THAN GC_high_water) GC_min_sp = GC_high_water;
 300         GC_words_allocd_at_reset = GC_words_allocd;
 301     }
 302 # endif
 303   return(arg);
 304 }
 305
 306
 307 /* Return a pointer to the base address of p, given a pointer to a      */
 308 /* an address within an object.  Return 0 o.w.                          */
 309 # ifdef __STDC__
 310     GC_PTR GC_base(GC_PTR p)
 311 # else
 312     GC_PTR GC_base(p)
 313     GC_PTR p;
 314 # endif
 315 {
 316     register word r;
 317     register struct hblk *h;
 318     register bottom_index *bi;
 319     register hdr *candidate_hdr;
 320     register word limit;
 321
 322     r = (word)p;
 323     if (!GC_is_initialized) return 0;
 324     h = HBLKPTR(r);
 325     GET_BI(r, bi);
 326     candidate_hdr = HDR_FROM_BI(bi, r);
 327     if (candidate_hdr == 0) return(0);
 328     /* If it's a pointer to the middle of a large object, move it       */
 329     /* to the beginning.                                                */
 330         while (IS_FORWARDING_ADDR_OR_NIL(candidate_hdr)) {
 331            h = FORWARDED_ADDR(h,candidate_hdr);
 332            r = (word)h + HDR_BYTES;
 333            candidate_hdr = HDR(h);
 334         }
 335     if (candidate_hdr -> hb_map == GC_invalid_map) return(0);
 336     /* Make sure r points to the beginning of the object */
 337         r &= ~(WORDS_TO_BYTES(1) - 1);
 338         {
 339             register int offset = (char *)r - (char *)(HBLKPTR(r));
 340             register signed_word sz = candidate_hdr -> hb_sz;
 341
 342 #           ifdef ALL_INTERIOR_POINTERS
 343               register map_entry_type map_entry;
 344
 345               map_entry = MAP_ENTRY((candidate_hdr -> hb_map), offset);
 346               if (map_entry == OBJ_INVALID) {
 347                 return(0);
 348               }
 349               r -= WORDS_TO_BYTES(map_entry);
 350               limit = r + WORDS_TO_BYTES(sz);
 351 #           else
 352               register int correction;
 353
 354               offset = BYTES_TO_WORDS(offset - HDR_BYTES);
 355               correction = offset % sz;
 356               r -= (WORDS_TO_BYTES(correction));
 357               limit = r + WORDS_TO_BYTES(sz);
 358               if (limit > (word)(h + 1)
 359                 && sz <= BYTES_TO_WORDS(HBLKSIZE) - HDR_WORDS) {
 360                 return(0);
 361               }
 362 #           endif
 363             if ((word)p >= limit) return(0);
 364         }
 365     return((GC_PTR)r);
 366 }
 367
 368
 369 /* Return the size of an object, given a pointer to its base.           */
 370 /* (For small obects this also happens to work from interior pointers,  */
 371 /* but that shouldn't be relied upon.)                                  */
 372 # ifdef __STDC__
 373     size_t GC_size(GC_PTR p)
 374 # else
 375     size_t GC_size(p)
 376     GC_PTR p;
 377 # endif
 378 {
 379     register int sz;
 380     register hdr * hhdr = HDR(p);
 381
 382     sz = WORDS_TO_BYTES(hhdr -> hb_sz);
 383     if (sz < 0) {
 384         return(-sz);
 385     } else {
 386         return(sz);
 387     }
 388 }
 389
 390 size_t GC_get_heap_size GC_PROTO(())
 391 {
 392     return ((size_t) GC_heapsize);
 393 }
 394
 395 size_t GC_get_bytes_since_gc GC_PROTO(())
 396 {
 397     return ((size_t) WORDS_TO_BYTES(GC_words_allocd));
 398 }
 399
 400 GC_bool GC_is_initialized = FALSE;
 401
 402 #if defined(SOLARIS_THREADS) || defined(IRIX_THREADS)
 403     extern void GC_thr_init();
 404 #endif
 405
 406 void GC_init()
 407 {
 408     DCL_LOCK_STATE;
 409
 410     DISABLE_SIGNALS();
 411     LOCK();
 412     GC_init_inner();
 413     UNLOCK();
 414     ENABLE_SIGNALS();
 415
 416 }
 417
 418 #ifdef MSWIN32
 419     extern void GC_init_win32();
 420 #endif
 421
 422 extern void GC_setpagesize();
 423
 424 void GC_init_inner()
 425 {
 426 #   ifndef THREADS
 427         word dummy;
 428 #   endif
 429
 430     if (GC_is_initialized) return;
 431     GC_setpagesize();
 432     GC_exclude_static_roots(beginGC_arrays, endGC_arrays);
 433 #   ifdef MSWIN32
 434         GC_init_win32();
 435 #   endif
 436 #   if defined(LINUX) && defined(POWERPC)
 437         GC_init_linuxppc();
 438 #   endif
 439 #   ifdef SOLARIS_THREADS
 440         GC_thr_init();
 441         /* We need dirty bits in order to find live stack sections.     */
 442         GC_dirty_init();
 443 #   endif
 444 #   if defined(IRIX_THREADS) || defined(LINUX_THREADS)
 445         GC_thr_init();
 446 #   endif
 447 #   if !defined(THREADS) || defined(SOLARIS_THREADS) || defined(WIN32_THREADS) \
 448        || defined(IRIX_THREADS) || defined(LINUX_THREADS) \
 449        || defined (QUICK_THREADS)
 450       if (GC_stackbottom == 0) {
 451           GC_stackbottom = GC_get_stack_base();
 452       }
 453 #   endif
 454     if  (sizeof (ptr_t) != sizeof(word)) {
 455         ABORT("sizeof (ptr_t) != sizeof(word)\n");
 456     }
 457     if  (sizeof (signed_word) != sizeof(word)) {
 458         ABORT("sizeof (signed_word) != sizeof(word)\n");
 459     }
 460     if  (sizeof (struct hblk) != HBLKSIZE) {
 461         ABORT("sizeof (struct hblk) != HBLKSIZE\n");
 462     }
 463 #   ifndef THREADS
 464 #     if defined(STACK_GROWS_UP) && defined(STACK_GROWS_DOWN)
 465         ABORT(
 466           "Only one of STACK_GROWS_UP and STACK_GROWS_DOWN should be defd\n");
 467 #     endif
 468 #     if !defined(STACK_GROWS_UP) && !defined(STACK_GROWS_DOWN)
 469         ABORT(
 470           "One of STACK_GROWS_UP and STACK_GROWS_DOWN should be defd\n");
 471 #     endif
 472 #     ifdef STACK_GROWS_DOWN
 473         if ((word)(&dummy) > (word)GC_stackbottom) {
 474           GC_err_printf0(
 475                 "STACK_GROWS_DOWN is defd, but stack appears to grow up\n");
 476 #         ifndef UTS4  /* Compiler bug workaround */
 477             GC_err_printf2("sp = 0x%lx, GC_stackbottom = 0x%lx\n",
 478                            (unsigned long) (&dummy),
 479                            (unsigned long) GC_stackbottom);
 480 #         endif
 481           ABORT("stack direction 3\n");
 482         }
 483 #     else
 484         if ((word)(&dummy) < (word)GC_stackbottom) {
 485           GC_err_printf0(
 486                 "STACK_GROWS_UP is defd, but stack appears to grow down\n");
 487           GC_err_printf2("sp = 0x%lx, GC_stackbottom = 0x%lx\n",
 488                          (unsigned long) (&dummy),
 489                          (unsigned long) GC_stackbottom);
 490           ABORT("stack direction 4");
 491         }
 492 #     endif
 493 #   endif
 494 #   if !defined(_AUX_SOURCE) || defined(__GNUC__)
 495       if ((word)(-1) < (word)0) {
 496         GC_err_printf0("The type word should be an unsigned integer type\n");
 497         GC_err_printf0("It appears to be signed\n");
 498         ABORT("word");
 499       }
 500 #   endif
 501     if ((signed_word)(-1) >= (signed_word)0) {
 502         GC_err_printf0(
 503                 "The type signed_word should be a signed integer type\n");
 504         GC_err_printf0("It appears to be unsigned\n");
 505         ABORT("signed_word");
 506     }
 507
 508     /* Add initial guess of root sets.  Do this first, since sbrk(0)    */
 509     /* might be used.                                                   */
 510       GC_register_data_segments();
 511     GC_init_headers();
 512     GC_bl_init();
 513     GC_mark_init();
 514     if (!GC_expand_hp_inner((word)MINHINCR)) {
 515         GC_err_printf0("Can't start up: not enough memory\n");
 516         EXIT();
 517     }
 518     /* Preallocate large object map.  It's otherwise inconvenient to    */
 519     /* deal with failure.                                               */
 520       if (!GC_add_map_entry((word)0)) {
 521         GC_err_printf0("Can't start up: not enough memory\n");
 522         EXIT();
 523       }
 524     GC_register_displacement_inner(0L);
 525 #   ifdef MERGE_SIZES
 526       GC_init_size_map();
 527 #   endif
 528 #   ifdef PCR
 529       if (PCR_IL_Lock(PCR_Bool_false, PCR_allSigsBlocked, PCR_waitForever)
 530           != PCR_ERes_okay) {
 531           ABORT("Can't lock load state\n");
 532       } else if (PCR_IL_Unlock() != PCR_ERes_okay) {
 533           ABORT("Can't unlock load state\n");
 534       }
 535       PCR_IL_Unlock();
 536       GC_pcr_install();
 537 #   endif
 538     /* Get black list set up */
 539       GC_gcollect_inner();
 540 #   ifdef STUBBORN_ALLOC
 541         GC_stubborn_init();
 542 #   endif
 543     GC_is_initialized = TRUE;
 544     /* Convince lint that some things are used */
 545 #   ifdef LINT
 546       {
 547           extern char * GC_copyright[];
 548           extern int GC_read();
 549           extern void GC_register_finalizer_no_order();
 550
 551           GC_noop(GC_copyright, GC_find_header,
 552                   GC_push_one, GC_call_with_alloc_lock, GC_read,
 553                   GC_dont_expand,
 554 #                 ifndef NO_DEBUGGING
 555                     GC_dump,
 556 #                 endif
 557                   GC_register_finalizer_no_order);
 558       }
 559 #   endif
 560 }
 561
 562 void GC_enable_incremental GC_PROTO(())
 563 {
 564     DCL_LOCK_STATE;
 565
 566 # ifndef FIND_LEAK
 567     DISABLE_SIGNALS();
 568     LOCK();
 569     if (GC_incremental) goto out;
 570     GC_setpagesize();
 571 #   ifdef MSWIN32
 572       {
 573         extern GC_bool GC_is_win32s();
 574
 575         /* VirtualProtect is not functional under win32s.       */
 576         if (GC_is_win32s()) goto out;
 577       }
 578 #   endif /* MSWIN32 */
 579 #   ifndef SOLARIS_THREADS
 580         GC_dirty_init();
 581 #   endif
 582     if (!GC_is_initialized) {
 583         GC_init_inner();
 584     }
 585     if (GC_dont_gc) {
 586         /* Can't easily do it. */
 587         UNLOCK();
 588         ENABLE_SIGNALS();
 589         return;
 590     }
 591     if (GC_words_allocd > 0) {
 592         /* There may be unmarked reachable objects      */
 593         GC_gcollect_inner();
 594     }   /* else we're OK in assuming everything's       */
 595         /* clean since nothing can point to an          */
 596         /* unmarked object.                             */
 597     GC_read_dirty();
 598     GC_incremental = TRUE;
 599 out:
 600     UNLOCK();
 601     ENABLE_SIGNALS();
 602 # endif
 603 }
 604
 605
 606 #ifdef MSWIN32
 607 # define LOG_FILE "gc.log"
 608
 609   HANDLE GC_stdout = 0, GC_stderr;
 610   int GC_tmp;
 611   DWORD GC_junk;
 612
 613   void GC_set_files()
 614   {
 615     if (!GC_stdout) {
 616         GC_stdout = CreateFile(LOG_FILE, GENERIC_WRITE,
 617                                FILE_SHARE_READ | FILE_SHARE_WRITE,
 618                                NULL, CREATE_ALWAYS, FILE_FLAG_WRITE_THROUGH,
 619                                NULL);
 620         if (INVALID_HANDLE_VALUE == GC_stdout) ABORT("Open of log file failed");
 621     }
 622     if (GC_stderr == 0) {
 623         GC_stderr = GC_stdout;
 624     }
 625   }
 626
 627 #endif
 628
 629 #if defined(OS2) || defined(MACOS)
 630 FILE * GC_stdout = NULL;
 631 FILE * GC_stderr = NULL;
 632 int GC_tmp;  /* Should really be local ... */
 633
 634   void GC_set_files()
 635   {
 636       if (GC_stdout == NULL) {
 637         GC_stdout = stdout;
 638     }
 639     if (GC_stderr == NULL) {
 640         GC_stderr = stderr;
 641     }
 642   }
 643 #endif
 644
 645 #if !defined(OS2) && !defined(MACOS) && !defined(MSWIN32)
 646   int GC_stdout = 1;
 647   int GC_stderr = 2;
 648 # if !defined(AMIGA)
 649 #   include <unistd.h>
 650 # endif
 651 #endif
 652
 653 #if !defined(MSWIN32)  && !defined(OS2) && !defined(MACOS) && !defined(ECOS)
 654 int GC_write(fd, buf, len)
 655 int fd;
 656 char *buf;
 657 size_t len;
 658 {
 659      register int bytes_written = 0;
 660      register int result;
 661
 662      while (bytes_written < len) {
 663 #       ifdef SOLARIS_THREADS
 664             result = syscall(SYS_write, fd, buf + bytes_written,
 665                                             len - bytes_written);
 666 #       else
 667             result = write(fd, buf + bytes_written, len - bytes_written);
 668 #       endif
 669         if (-1 == result) return(result);
 670         bytes_written += result;
 671     }
 672     return(bytes_written);
 673 }
 674 #endif /* UN*X */
 675
 676 #if defined(ECOS)
 677 int GC_write(fd, buf, len)
 678 {
 679   _Jv_diag_write (buf, len);
 680   return len;
 681 }
 682 #endif
 683
 684
 685 #ifdef MSWIN32
 686 #   define WRITE(f, buf, len) (GC_set_files(), \
 687                                GC_tmp = WriteFile((f), (buf), \
 688                                                   (len), &GC_junk, NULL),\
 689                                (GC_tmp? 1 : -1))
 690 #else
 691 #   if defined(OS2) || defined(MACOS)
 692 #   define WRITE(f, buf, len) (GC_set_files(), \
 693                                GC_tmp = fwrite((buf), 1, (len), (f)), \
 694                                fflush(f), GC_tmp)
 695 #   else
 696 #     define WRITE(f, buf, len) GC_write((f), (buf), (len))
 697 #   endif
 698 #endif
 699
 700 /* A version of printf that is unlikely to call malloc, and is thus safer */
 701 /* to call from the collector in case malloc has been bound to GC_malloc. */
 702 /* Assumes that no more than 1023 characters are written at once.         */
 703 /* Assumes that all arguments have been converted to something of the     */
 704 /* same size as long, and that the format conversions expect something    */
 705 /* of that size.                                                          */
 706 void GC_printf(format, a, b, c, d, e, f)
 707 char * format;
 708 long a, b, c, d, e, f;
 709 {
 710     char buf[1025];
 711
 712     if (GC_quiet) return;
 713     buf[1024] = 0x15;
 714     (void) sprintf(buf, format, a, b, c, d, e, f);
 715     if (buf[1024] != 0x15) ABORT("GC_printf clobbered stack");
 716     if (WRITE(GC_stdout, buf, strlen(buf)) < 0) ABORT("write to stdout failed");
 717 }
 718
 719 void GC_err_printf(format, a, b, c, d, e, f)
 720 char * format;
 721 long a, b, c, d, e, f;
 722 {
 723     char buf[1025];
 724
 725     buf[1024] = 0x15;
 726     (void) sprintf(buf, format, a, b, c, d, e, f);
 727     if (buf[1024] != 0x15) ABORT("GC_err_printf clobbered stack");
 728     if (WRITE(GC_stderr, buf, strlen(buf)) < 0) ABORT("write to stderr failed");
 729 }
 730
 731 void GC_err_puts(s)
 732 char *s;
 733 {
 734     if (WRITE(GC_stderr, s, strlen(s)) < 0) ABORT("write to stderr failed");
 735 }
 736
 737 # if defined(__STDC__) || defined(__cplusplus)
 738     void GC_default_warn_proc(char *msg, GC_word arg)
 739 # else
 740     void GC_default_warn_proc(msg, arg)
 741     char *msg;
 742     GC_word arg;
 743 # endif
 744 {
 745     GC_err_printf1(msg, (unsigned long)arg);
 746 }
 747
 748 GC_warn_proc GC_current_warn_proc = GC_default_warn_proc;
 749
 750 # if defined(__STDC__) || defined(__cplusplus)
 751     GC_warn_proc GC_set_warn_proc(GC_warn_proc p)
 752 # else
 753     GC_warn_proc GC_set_warn_proc(p)
 754     GC_warn_proc p;
 755 # endif
 756 {
 757     GC_warn_proc result;
 758
 759     LOCK();
 760     result = GC_current_warn_proc;
 761     GC_current_warn_proc = p;
 762     UNLOCK();
 763     return(result);
 764 }
 765
 766
 767 #ifndef PCR
 768 void GC_abort(msg)
 769 char * msg;
 770 {
 771     GC_err_printf1("%s\n", msg);
 772     (void) abort();
 773 }
 774 #endif
 775
 776 #ifdef NEED_CALLINFO
 777
 778 void GC_print_callers (info)
 779 struct callinfo info[NFRAMES];
 780 {
 781     register int i,j;
 782
 783 #   if NFRAMES == 1
 784       GC_err_printf0("\tCaller at allocation:\n");
 785 #   else
 786       GC_err_printf0("\tCall chain at allocation:\n");
 787 #   endif
 788     for (i = 0; i < NFRAMES; i++) {
 789         if (info[i].ci_pc == 0) break;
 790 #       if NARGS > 0
 791           GC_err_printf0("\t\targs: ");
 792           for (j = 0; j < NARGS; j++) {
 793             if (j != 0) GC_err_printf0(", ");
 794             GC_err_printf2("%d (0x%X)", ~(info[i].ci_arg[j]),
 795                                         ~(info[i].ci_arg[j]));
 796           }
 797           GC_err_printf0("\n");
 798 #       endif
 799         GC_err_printf1("\t\t##PC##= 0x%X\n", info[i].ci_pc);
 800     }
 801 }
 802
 803 #endif /* SAVE_CALL_CHAIN */
 804
 805 # ifdef SRC_M3
 806 void GC_enable()
 807 {
 808     GC_dont_gc--;
 809 }
 810
 811 void GC_disable()
 812 {
 813     GC_dont_gc++;
 814 }
 815 # endif
 816
 817 #if !defined(NO_DEBUGGING)
 818
 819 void GC_dump()
 820 {
 821     GC_printf0("***Static roots:\n");
 822     GC_print_static_roots();
 823     GC_printf0("\n***Heap sections:\n");
 824     GC_print_heap_sects();
 825     GC_printf0("\n***Free blocks:\n");
 826     GC_print_hblkfreelist();
 827     GC_printf0("\n***Blocks in use:\n");
 828     GC_print_block_list();
 829 }
 830
 831 # endif /* NO_DEBUGGING */