/*

* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers

* Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.

* Copyright 1996-1999 by Silicon Graphics. All rights reserved.

* Copyright 1999 by Hewlett-Packard Company. All rights reserved.

*

* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED

* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.

*

* Permission is hereby granted to use or copy this program

* for any purpose, provided the above notices are retained on all copies.

* Permission to modify the code and to distribute modified code is granted,

* provided the above notices are retained, and a notice that the code was

* modified is included with the above copyright notice.

*/

/*

* Note that this defines a large number of tuning hooks, which can

* safely be ignored in nearly all cases. For normal use it suffices

* to call only GC_MALLOC and perhaps GC_REALLOC.

* For better performance, also look at GC_MALLOC_ATOMIC, and

* GC_enable_incremental. If you need an action to be performed

* immediately before an object is collected, look at GC_register_finalizer.

* If you are using Solaris threads, look at the end of this file.

* Everything else is best ignored unless you encounter performance

* problems.

*/

#ifndef _GC_H

# define _GC_H

# define __GC

# include <stddef.h>

#if defined(__CYGWIN32__) && defined(GC_USE_DLL)

#include "libgc_globals.h"

#endif

#if defined(__MINGW32__) && defined(WIN32_THREADS)

# ifdef GC_BUILD

# define GC_API __declspec(dllexport)

# else

# define GC_API __declspec(dllimport)

# endif

#endif

#if defined(_MSC_VER) && defined(_DLL)

# ifdef GC_BUILD

# define GC_API __declspec(dllexport)

# else

# define GC_API __declspec(dllimport)

# endif

#endif

#if defined(__WATCOMC__) && defined(GC_DLL)

# ifdef GC_BUILD

# define GC_API extern __declspec(dllexport)

# else

# define GC_API extern __declspec(dllimport)

# endif

#endif

#ifndef GC_API

#define GC_API extern

#endif

# if defined(__STDC__) || defined(__cplusplus)

# define GC_PROTO(args) args

typedef void * GC_PTR;

# define GC_CONST const

# else

# define GC_PROTO(args) ()

typedef char * GC_PTR;

# define GC_CONST

# endif

# ifdef __cplusplus

extern "C" {

# endif

/* Define word and signed_word to be unsigned and signed types of the */

/* size as char * or void *. There seems to be no way to do this */

/* even semi-portably. The following is probably no better/worse */

/* than almost anything else. */

/* The ANSI standard suggests that size_t and ptr_diff_t might be */

/* better choices. But those appear to have incorrect definitions */

/* on may systems. Notably "typedef int size_t" seems to be both */

/* frequent and WRONG. */

typedef unsigned long GC_word;

typedef long GC_signed_word;

/* Public read-only variables */

GC_API GC_word GC_gc_no;/* Counter incremented per collection. */

/* Includes empty GCs at startup. */

/* Public R/W variables */

GC_API GC_PTR (*GC_oom_fn) GC_PROTO((size_t bytes_requested));

/* When there is insufficient memory to satisfy */

/* an allocation request, we return */

/* (*GC_oom_fn)(). By default this just */

/* returns 0. */

/* If it returns, it must return 0 or a valid */

/* pointer to a previously allocated heap */

/* object. */

GC_API int GC_find_leak;

/* Do not actually garbage collect, but simply */

/* report inaccessible memory that was not */

/* deallocated with GC_free. Initial value */

/* is determined by FIND_LEAK macro. */

GC_API int GC_quiet; /* Disable statistics output. Only matters if */

/* collector has been compiled with statistics */

/* enabled. This involves a performance cost, */

/* and is thus not the default. */

GC_API int GC_finalize_on_demand;

/* If nonzero, finalizers will only be run in */

/* response to an eplit GC_invoke_finalizers */

/* call. The default is determined by whether */

/* the FINALIZE_ON_DEMAND macro is defined */

/* when the collector is built. */

GC_API int GC_java_finalization;

/* Mark objects reachable from finalizable */

/* objects in a separate postpass. This makes */

/* it a bit safer to use non-topologically- */

/* ordered finalization. Default value is */

/* determined by JAVA_FINALIZATION macro. */

GC_API int GC_dont_gc; /* Dont collect unless explicitly requested, e.g. */

/* because it's not safe. */

GC_API int GC_dont_expand;

/* Dont expand heap unless explicitly requested */

/* or forced to. */

GC_API int GC_use_entire_heap;

/* Causes the nonincremental collector to use the */

/* entire heap before collecting. This was the only */

/* option for GC versions < 5.0. This sometimes */

/* results in more large block fragmentation, since */

/* very larg blocks will tend to get broken up */

/* during each GC cycle. It is likely to result in a */

/* larger working set, but lower collection */

/* frequencies, and hence fewer instructions executed */

/* in the collector. */

GC_API int GC_full_freq; /* Number of partial collections between */

/* full collections. Matters only if */

/* GC_incremental is set. */

/* Full collections are also triggered if */

/* the collector detects a substantial */

/* increase in the number of in-use heap */

/* blocks. Values in the tens are now */

/* perfectly reasonable, unlike for */

/* earlier GC versions. */

GC_API GC_word GC_non_gc_bytes;

/* Bytes not considered candidates for collection. */

/* Used only to control scheduling of collections. */

GC_API GC_word GC_free_space_divisor;

/* We try to make sure that we allocate at */

/* least N/GC_free_space_divisor bytes between */

/* collections, where N is the heap size plus */

/* a rough estimate of the root set size. */

/* Initially, GC_free_space_divisor = 4. */

/* Increasing its value will use less space */

/* but more collection time. Decreasing it */

/* will appreciably decrease collection time */

/* at the expense of space. */

/* GC_free_space_divisor = 1 will effectively */

/* disable collections. */

GC_API GC_word GC_max_retries;

/* The maximum number of GCs attempted before */

/* reporting out of memory after heap */

/* expansion fails. Initially 0. */

GC_API char *GC_stackbottom; /* Cool end of user stack. */

/* May be set in the client prior to */

/* calling any GC_ routines. This */

/* avoids some overhead, and */

/* potentially some signals that can */

/* confuse debuggers. Otherwise the */

/* collector attempts to set it */

/* automatically. */

/* For multithreaded code, this is the */

/* cold end of the stack for the */

/* primordial thread. */

/* Public procedures */

/*

* general purpose allocation routines, with roughly malloc calling conv.

* The atomic versions promise that no relevant pointers are contained

* in the object. The nonatomic versions guarantee that the new object

* is cleared. GC_malloc_stubborn promises that no changes to the object

* will occur after GC_end_stubborn_change has been called on the

* result of GC_malloc_stubborn. GC_malloc_uncollectable allocates an object

* that is scanned for pointers to collectable objects, but is not itself

* collectable. GC_malloc_uncollectable and GC_free called on the resulting

* object implicitly update GC_non_gc_bytes appropriately.

*/

GC_API GC_PTR GC_malloc GC_PROTO((size_t size_in_bytes));

GC_API GC_PTR GC_malloc_atomic GC_PROTO((size_t size_in_bytes));

GC_API GC_PTR GC_malloc_uncollectable GC_PROTO((size_t size_in_bytes));

GC_API GC_PTR GC_malloc_stubborn GC_PROTO((size_t size_in_bytes));

/* The following is only defined if the library has been suitably */

/* compiled: */

GC_API GC_PTR GC_malloc_atomic_uncollectable GC_PROTO((size_t size_in_bytes));

/* Explicitly deallocate an object. Dangerous if used incorrectly. */

/* Requires a pointer to the base of an object. */

/* If the argument is stubborn, it should not be changeable when freed. */

/* An object should not be enable for finalization when it is */

/* explicitly deallocated. */

/* GC_free(0) is a no-op, as required by ANSI C for free. */

GC_API void GC_free GC_PROTO((GC_PTR object_addr));

/*

* Stubborn objects may be changed only if the collector is explicitly informed.

* The collector is implicitly informed of coming change when such

* an object is first allocated. The following routines inform the

* collector that an object will no longer be changed, or that it will

* once again be changed. Only nonNIL pointer stores into the object

* are considered to be changes. The argument to GC_end_stubborn_change

* must be exacly the value returned by GC_malloc_stubborn or passed to

* GC_change_stubborn. (In the second case it may be an interior pointer

* within 512 bytes of the beginning of the objects.)

* There is a performance penalty for allowing more than

* one stubborn object to be changed at once, but it is acceptable to

* do so. The same applies to dropping stubborn objects that are still

* changeable.

*/

GC_API void GC_change_stubborn GC_PROTO((GC_PTR));

GC_API void GC_end_stubborn_change GC_PROTO((GC_PTR));

/* Return a pointer to the base (lowest address) of an object given */

/* a pointer to a location within the object. */

/* Return 0 if displaced_pointer doesn't point to within a valid */

/* object. */

GC_API GC_PTR GC_base GC_PROTO((GC_PTR displaced_pointer));

/* Given a pointer to the base of an object, return its size in bytes. */

/* The returned size may be slightly larger than what was originally */

/* requested. */

GC_API size_t GC_size GC_PROTO((GC_PTR object_addr));

/* For compatibility with C library. This is occasionally faster than */

/* a malloc followed by a bcopy. But if you rely on that, either here */

/* or with the standard C library, your code is broken. In my */

/* opinion, it shouldn't have been invented, but now we're stuck. -HB */

/* The resulting object has the same kind as the original. */

/* If the argument is stubborn, the result will have changes enabled. */

/* It is an error to have changes enabled for the original object. */

/* Follows ANSI comventions for NULL old_object. */

GC_API GC_PTR GC_realloc

GC_PROTO((GC_PTR old_object, size_t new_size_in_bytes));

/* Explicitly increase the heap size. */

/* Returns 0 on failure, 1 on success. */

GC_API int GC_expand_hp GC_PROTO((size_t number_of_bytes));

/* Limit the heap size to n bytes. Useful when you're debugging, */

/* especially on systems that don't handle running out of memory well. */

/* n == 0 ==> unbounded. This is the default. */

GC_API void GC_set_max_heap_size GC_PROTO((GC_word n));

/* Inform the collector that a certain section of statically allocated */

/* memory contains no pointers to garbage collected memory. Thus it */

/* need not be scanned. This is sometimes important if the application */

/* maps large read/write files into the address space, which could be */

/* mistaken for dynamic library data segments on some systems. */

GC_API void GC_exclude_static_roots GC_PROTO((GC_PTR start, GC_PTR finish));

/* Clear the set of root segments. Wizards only. */

GC_API void GC_clear_roots GC_PROTO((void));

/* Add a root segment. Wizards only. */

GC_API void GC_add_roots GC_PROTO((char * low_address,

char * high_address_plus_1));

/* Add a displacement to the set of those considered valid by the */

/* collector. GC_register_displacement(n) means that if p was returned */

/* by GC_malloc, then (char *)p + n will be considered to be a valid */

/* pointer to n. N must be small and less than the size of p. */

/* (All pointers to the interior of objects from the stack are */

/* considered valid in any case. This applies to heap objects and */

/* static data.) */

/* Preferably, this should be called before any other GC procedures. */

/* Calling it later adds to the probability of excess memory */

/* retention. */

/* This is a no-op if the collector was compiled with recognition of */

/* arbitrary interior pointers enabled, which is now the default. */

GC_API void GC_register_displacement GC_PROTO((GC_word n));

/* The following version should be used if any debugging allocation is */

/* being done. */

GC_API void GC_debug_register_displacement GC_PROTO((GC_word n));

/* Explicitly trigger a full, world-stop collection. */

GC_API void GC_gcollect GC_PROTO((void));

/* Trigger a full world-stopped collection. Abort the collection if */

/* and when stop_func returns a nonzero value. Stop_func will be */

/* called frequently, and should be reasonably fast. This works even */

/* if virtual dirty bits, and hence incremental collection is not */

/* available for this architecture. Collections can be aborted faster */

/* than normal pause times for incremental collection. However, */

/* aborted collections do no useful work; the next collection needs */

/* to start from the beginning. */

/* Return 0 if the collection was aborted, 1 if it succeeded. */

typedef int (* GC_stop_func) GC_PROTO((void));

GC_API int GC_try_to_collect GC_PROTO((GC_stop_func stop_func));

/* Return the number of bytes in the heap. Excludes collector private */

/* data structures. Includes empty blocks and fragmentation loss. */

/* Includes some pages that were allocated but never written. */

GC_API size_t GC_get_heap_size GC_PROTO((void));

/* Return a lower bound on the number of free bytes in the heap. */

GC_API size_t GC_get_free_bytes GC_PROTO((void));

/* Return the number of bytes allocated since the last collection. */

GC_API size_t GC_get_bytes_since_gc GC_PROTO((void));

/* Enable incremental/generational collection. */

/* Not advisable unless dirty bits are */

/* available or most heap objects are */

/* pointerfree(atomic) or immutable. */

/* Don't use in leak finding mode. */

/* Ignored if GC_dont_gc is true. */

GC_API void GC_enable_incremental GC_PROTO((void));

/* Perform some garbage collection work, if appropriate. */

/* Return 0 if there is no more work to be done. */

/* Typically performs an amount of work corresponding roughly */

/* to marking from one page. May do more work if further */

/* progress requires it, e.g. if incremental collection is */

/* disabled. It is reasonable to call this in a wait loop */

/* until it returns 0. */

GC_API int GC_collect_a_little GC_PROTO((void));

/* Allocate an object of size lb bytes. The client guarantees that */

/* as long as the object is live, it will be referenced by a pointer */

/* that points to somewhere within the first 256 bytes of the object. */

/* (This should normally be declared volatile to prevent the compiler */

/* from invalidating this assertion.) This routine is only useful */

/* if a large array is being allocated. It reduces the chance of */

/* accidentally retaining such an array as a result of scanning an */

/* integer that happens to be an address inside the array. (Actually, */

/* it reduces the chance of the allocator not finding space for such */

/* an array, since it will try hard to avoid introducing such a false */

/* reference.) On a SunOS 4.X or MS Windows system this is recommended */

/* for arrays likely to be larger than 100K or so. For other systems, */

/* or if the collector is not configured to recognize all interior */

/* pointers, the threshold is normally much higher. */

GC_API GC_PTR GC_malloc_ignore_off_page GC_PROTO((size_t lb));

GC_API GC_PTR GC_malloc_atomic_ignore_off_page GC_PROTO((size_t lb));

#if defined(__sgi) && !defined(__GNUC__) && _COMPILER_VERSION >= 720

# define GC_ADD_CALLER

# define GC_RETURN_ADDR (GC_word)__return_address

#endif

#ifdef GC_ADD_CALLER

# define GC_EXTRAS GC_RETURN_ADDR, __FILE__, __LINE__

# define GC_EXTRA_PARAMS GC_word ra, GC_CONST char * s, int i

#else

# define GC_EXTRAS __FILE__, __LINE__

# define GC_EXTRA_PARAMS GC_CONST char * s, int i

#endif

/* Debugging (annotated) allocation. GC_gcollect will check */

/* objects allocated in this way for overwrites, etc. */

GC_API GC_PTR GC_debug_malloc

GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS));

GC_API GC_PTR GC_debug_malloc_atomic

GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS));

GC_API GC_PTR GC_debug_malloc_uncollectable

GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS));

GC_API GC_PTR GC_debug_malloc_stubborn

GC_PROTO((size_t size_in_bytes, GC_EXTRA_PARAMS));

GC_API void GC_debug_free GC_PROTO((GC_PTR object_addr));

GC_API GC_PTR GC_debug_realloc

GC_PROTO((GC_PTR old_object, size_t new_size_in_bytes,

GC_EXTRA_PARAMS));

GC_API void GC_debug_change_stubborn GC_PROTO((GC_PTR));

GC_API void GC_debug_end_stubborn_change GC_PROTO((GC_PTR));

# ifdef GC_DEBUG

# define GC_MALLOC(sz) GC_debug_malloc(sz, GC_EXTRAS)

# define GC_MALLOC_ATOMIC(sz) GC_debug_malloc_atomic(sz, GC_EXTRAS)

# define GC_MALLOC_UNCOLLECTABLE(sz) GC_debug_malloc_uncollectable(sz, \

GC_EXTRAS)

# define GC_REALLOC(old, sz) GC_debug_realloc(old, sz, GC_EXTRAS)

# define GC_FREE(p) GC_debug_free(p)

# define GC_REGISTER_FINALIZER(p, f, d, of, od) \

GC_debug_register_finalizer(p, f, d, of, od)

# define GC_REGISTER_FINALIZER_IGNORE_SELF(p, f, d, of, od) \

GC_debug_register_finalizer_ignore_self(p, f, d, of, od)

# define GC_REGISTER_FINALIZER_NO_ORDER(p, f, d, of, od) \

GC_debug_register_finalizer_no_order(p, f, d, of, od)

# define GC_MALLOC_STUBBORN(sz) GC_debug_malloc_stubborn(sz, GC_EXTRAS);

# define GC_CHANGE_STUBBORN(p) GC_debug_change_stubborn(p)

# define GC_END_STUBBORN_CHANGE(p) GC_debug_end_stubborn_change(p)

# define GC_GENERAL_REGISTER_DISAPPEARING_LINK(link, obj) \

GC_general_register_disappearing_link(link, GC_base(obj))

# define GC_REGISTER_DISPLACEMENT(n) GC_debug_register_displacement(n)

# else

# define GC_MALLOC(sz) GC_malloc(sz)

# define GC_MALLOC_ATOMIC(sz) GC_malloc_atomic(sz)

# define GC_MALLOC_UNCOLLECTABLE(sz) GC_malloc_uncollectable(sz)

# define GC_REALLOC(old, sz) GC_realloc(old, sz)

# define GC_FREE(p) GC_free(p)

# define GC_REGISTER_FINALIZER(p, f, d, of, od) \

GC_register_finalizer(p, f, d, of, od)

# define GC_REGISTER_FINALIZER_IGNORE_SELF(p, f, d, of, od) \

GC_register_finalizer_ignore_self(p, f, d, of, od)

# define GC_REGISTER_FINALIZER_NO_ORDER(p, f, d, of, od) \

GC_register_finalizer_no_order(p, f, d, of, od)

# define GC_MALLOC_STUBBORN(sz) GC_malloc_stubborn(sz)

# define GC_CHANGE_STUBBORN(p) GC_change_stubborn(p)

# define GC_END_STUBBORN_CHANGE(p) GC_end_stubborn_change(p)

# define GC_GENERAL_REGISTER_DISAPPEARING_LINK(link, obj) \

GC_general_register_disappearing_link(link, obj)

# define GC_REGISTER_DISPLACEMENT(n) GC_register_displacement(n)

# endif

/* The following are included because they are often convenient, and */

/* reduce the chance for a misspecifed size argument. But calls may */

/* expand to something syntactically incorrect if t is a complicated */

/* type expression. */

# define GC_NEW(t) (t *)GC_MALLOC(sizeof (t))

# define GC_NEW_ATOMIC(t) (t *)GC_MALLOC_ATOMIC(sizeof (t))

# define GC_NEW_STUBBORN(t) (t *)GC_MALLOC_STUBBORN(sizeof (t))

# define GC_NEW_UNCOLLECTABLE(t) (t *)GC_MALLOC_UNCOLLECTABLE(sizeof (t))

/* Finalization. Some of these primitives are grossly unsafe. */

/* The idea is to make them both cheap, and sufficient to build */

/* a safer layer, closer to PCedar finalization. */

/* The interface represents my conclusions from a long discussion */

/* with Alan Demers, Dan Greene, Carl Hauser, Barry Hayes, */

/* Christian Jacobi, and Russ Atkinson. It's not perfect, and */

/* probably nobody else agrees with it. Hans-J. Boehm 3/13/92 */

typedef void (*GC_finalization_proc)

GC_PROTO((GC_PTR obj, GC_PTR client_data));

GC_API void GC_register_finalizer

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

GC_API void GC_debug_register_finalizer

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

/* When obj is no longer accessible, invoke */

/* (*fn)(obj, cd). If a and b are inaccessible, and */

/* a points to b (after disappearing links have been */

/* made to disappear), then only a will be */

/* finalized. (If this does not create any new */

/* pointers to b, then b will be finalized after the */

/* next collection.) Any finalizable object that */

/* is reachable from itself by following one or more */

/* pointers will not be finalized (or collected). */

/* Thus cycles involving finalizable objects should */

/* be avoided, or broken by disappearing links. */

/* All but the last finalizer registered for an object */

/* is ignored. */

/* Finalization may be removed by passing 0 as fn. */

/* Finalizers are implicitly unregistered just before */

/* they are invoked. */

/* The old finalizer and client data are stored in */

/* *ofn and *ocd. */

/* Fn is never invoked on an accessible object, */

/* provided hidden pointers are converted to real */

/* pointers only if the allocation lock is held, and */

/* such conversions are not performed by finalization */

/* routines. */

/* If GC_register_finalizer is aborted as a result of */

/* a signal, the object may be left with no */

/* finalization, even if neither the old nor new */

/* finalizer were NULL. */

/* Obj should be the nonNULL starting address of an */

/* object allocated by GC_malloc or friends. */

/* Note that any garbage collectable object referenced */

/* by cd will be considered accessible until the */

/* finalizer is invoked. */

/* Another versions of the above follow. It ignores */

/* self-cycles, i.e. pointers from a finalizable object to */

/* itself. There is a stylistic argument that this is wrong, */

/* but it's unavoidable for C++, since the compiler may */

/* silently introduce these. It's also benign in that specific */

/* case. */

GC_API void GC_register_finalizer_ignore_self

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

GC_API void GC_debug_register_finalizer_ignore_self

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

/* Another version of the above. It ignores all cycles. */

/* It should probably only be used by Java implementations. */

GC_API void GC_register_finalizer_no_order

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

GC_API void GC_debug_register_finalizer_no_order

GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,

GC_finalization_proc *ofn, GC_PTR *ocd));

/* The following routine may be used to break cycles between */

/* finalizable objects, thus causing cyclic finalizable */

/* objects to be finalized in the correct order. Standard */

/* use involves calling GC_register_disappearing_link(&p), */

/* where p is a pointer that is not followed by finalization */

/* code, and should not be considered in determining */

/* finalization order. */

GC_API int GC_register_disappearing_link GC_PROTO((GC_PTR * /* link */));

/* Link should point to a field of a heap allocated */

/* object obj. *link will be cleared when obj is */

/* found to be inaccessible. This happens BEFORE any */

/* finalization code is invoked, and BEFORE any */

/* decisions about finalization order are made. */

/* This is useful in telling the finalizer that */

/* some pointers are not essential for proper */

/* finalization. This may avoid finalization cycles. */

/* Note that obj may be resurrected by another */

/* finalizer, and thus the clearing of *link may */

/* be visible to non-finalization code. */

/* There's an argument that an arbitrary action should */

/* be allowed here, instead of just clearing a pointer. */

/* But this causes problems if that action alters, or */

/* examines connectivity. */

/* Returns 1 if link was already registered, 0 */

/* otherwise. */

/* Only exists for backward compatibility. See below: */

GC_API int GC_general_register_disappearing_link

GC_PROTO((GC_PTR * /* link */, GC_PTR obj));

/* A slight generalization of the above. *link is */

/* cleared when obj first becomes inaccessible. This */

/* can be used to implement weak pointers easily and */

/* safely. Typically link will point to a location */

/* holding a disguised pointer to obj. (A pointer */

/* inside an "atomic" object is effectively */

/* disguised.) In this way soft */

/* pointers are broken before any object */

/* reachable from them are finalized. Each link */

/* May be registered only once, i.e. with one obj */

/* value. This was added after a long email discussion */

/* with John Ellis. */

/* Obj must be a pointer to the first word of an object */

/* we allocated. It is unsafe to explicitly deallocate */

/* the object containing link. Explicitly deallocating */

/* obj may or may not cause link to eventually be */

/* cleared. */

GC_API int GC_unregister_disappearing_link GC_PROTO((GC_PTR * /* link */));

/* Returns 0 if link was not actually registered. */

/* Undoes a registration by either of the above two */

/* routines. */

/* Auxiliary fns to make finalization work correctly with displaced */

/* pointers introduced by the debugging allocators. */

GC_API GC_PTR GC_make_closure GC_PROTO((GC_finalization_proc fn, GC_PTR data));

GC_API void GC_debug_invoke_finalizer GC_PROTO((GC_PTR obj, GC_PTR data));

/* Returns !=0 if GC_invoke_finalizers has something to do. */

GC_API int GC_should_invoke_finalizers GC_PROTO((void));

GC_API int GC_invoke_finalizers GC_PROTO((void));

/* Run finalizers for all objects that are ready to */

/* be finalized. Return the number of finalizers */

/* that were run. Normally this is also called */

/* implicitly during some allocations. If */

/* GC-finalize_on_demand is nonzero, it must be called */

/* explicitly. */

/* GC_set_warn_proc can be used to redirect or filter warning messages. */

/* p may not be a NULL pointer. */

typedef void (*GC_warn_proc) GC_PROTO((char *msg, GC_word arg));

GC_API GC_warn_proc GC_set_warn_proc GC_PROTO((GC_warn_proc p));

/* Returns old warning procedure. */

/* The following is intended to be used by a higher level */

/* (e.g. cedar-like) finalization facility. It is expected */

/* that finalization code will arrange for hidden pointers to */

/* disappear. Otherwise objects can be accessed after they */

/* have been collected. */

/* Note that putting pointers in atomic objects or in */

/* nonpointer slots of "typed" objects is equivalent to */

/* disguising them in this way, and may have other advantages. */

# if defined(I_HIDE_POINTERS) || defined(GC_I_HIDE_POINTERS)

typedef GC_word GC_hidden_pointer;

# define HIDE_POINTER(p) (~(GC_hidden_pointer)(p))

# define REVEAL_POINTER(p) ((GC_PTR)(HIDE_POINTER(p)))

/* Converting a hidden pointer to a real pointer requires verifying */

/* that the object still exists. This involves acquiring the */

/* allocator lock to avoid a race with the collector. */

# endif /* I_HIDE_POINTERS */

typedef GC_PTR (*GC_fn_type) GC_PROTO((GC_PTR client_data));

GC_API GC_PTR GC_call_with_alloc_lock

GC_PROTO((GC_fn_type fn, GC_PTR client_data));

/* Check that p and q point to the same object. */

/* Fail conspicuously if they don't. */

/* Returns the first argument. */

/* Succeeds if neither p nor q points to the heap. */

/* May succeed if both p and q point to between heap objects. */

GC_API GC_PTR GC_same_obj GC_PROTO((GC_PTR p, GC_PTR q));

/* Checked pointer pre- and post- increment operations. Note that */

/* the second argument is in units of bytes, not multiples of the */

/* object size. This should either be invoked from a macro, or the */

/* call should be automatically generated. */

GC_API GC_PTR GC_pre_incr GC_PROTO((GC_PTR *p, size_t how_much));

GC_API GC_PTR GC_post_incr GC_PROTO((GC_PTR *p, size_t how_much));

/* Check that p is visible */

/* to the collector as a possibly pointer containing location. */

/* If it isn't fail conspicuously. */

/* Returns the argument in all cases. May erroneously succeed */

/* in hard cases. (This is intended for debugging use with */

/* untyped allocations. The idea is that it should be possible, though */

/* slow, to add such a call to all indirect pointer stores.) */

/* Currently useless for multithreaded worlds. */

GC_API GC_PTR GC_is_visible GC_PROTO((GC_PTR p));

/* Check that if p is a pointer to a heap page, then it points to */

/* a valid displacement within a heap object. */

/* Fail conspicuously if this property does not hold. */

/* Uninteresting with ALL_INTERIOR_POINTERS. */

/* Always returns its argument. */

GC_API GC_PTR GC_is_valid_displacement GC_PROTO((GC_PTR p));

/* Safer, but slow, pointer addition. Probably useful mainly with */

/* a preprocessor. Useful only for heap pointers. */

#ifdef GC_DEBUG

# define GC_PTR_ADD3(x, n, type_of_result) \

((type_of_result)GC_same_obj((x)+(n), (x)))

# define GC_PRE_INCR3(x, n, type_of_result) \

((type_of_result)GC_pre_incr(&(x), (n)*sizeof(*x))

# define GC_POST_INCR2(x, type_of_result) \

((type_of_result)GC_post_incr(&(x), sizeof(*x))

# ifdef __GNUC__

# define GC_PTR_ADD(x, n) \

GC_PTR_ADD3(x, n, typeof(x))

# define GC_PRE_INCR(x, n) \

GC_PRE_INCR3(x, n, typeof(x))

# define GC_POST_INCR(x, n) \

GC_POST_INCR3(x, typeof(x))

# else

/* We can't do this right without typeof, which ANSI */

/* decided was not sufficiently useful. Repeatedly */

/* mentioning the arguments seems too dangerous to be */

/* useful. So does not casting the result. */

# define GC_PTR_ADD(x, n) ((x)+(n))

# endif

#else /* !GC_DEBUG */

# define GC_PTR_ADD3(x, n, type_of_result) ((x)+(n))

# define GC_PTR_ADD(x, n) ((x)+(n))

# define GC_PRE_INCR3(x, n, type_of_result) ((x) += (n))

# define GC_PRE_INCR(x, n) ((x) += (n))

# define GC_POST_INCR2(x, n, type_of_result) ((x)++)

# define GC_POST_INCR(x, n) ((x)++)

#endif

/* Safer assignment of a pointer to a nonstack location. */

#ifdef GC_DEBUG

# ifdef __STDC__

# define GC_PTR_STORE(p, q) \

(*(void **)GC_is_visible(p) = GC_is_valid_displacement(q))

# else

# define GC_PTR_STORE(p, q) \

(*(char **)GC_is_visible(p) = GC_is_valid_displacement(q))

# endif

#else /* !GC_DEBUG */

# define GC_PTR_STORE(p, q) *((p) = (q))

#endif

/* Fynctions called to report pointer checking errors */

GC_API void (*GC_same_obj_print_proc) GC_PROTO((GC_PTR p, GC_PTR q));

GC_API void (*GC_is_valid_displacement_print_proc)

GC_PROTO((GC_PTR p));

GC_API void (*GC_is_visible_print_proc)

GC_PROTO((GC_PTR p));

#if defined(_SOLARIS_PTHREADS) && !defined(SOLARIS_THREADS)

# define SOLARIS_THREADS

#endif

#ifdef SOLARIS_THREADS

/* We need to intercept calls to many of the threads primitives, so */

/* that we can locate thread stacks and stop the world. */

/* Note also that the collector cannot see thread specific data. */

/* Thread specific data should generally consist of pointers to */

/* uncollectable objects, which are deallocated using the destructor */

/* facility in thr_keycreate. */

# include <thread.h>

# include <signal.h>

int GC_thr_create(void *stack_base, size_t stack_size,

void *(*start_routine)(void *), void *arg, long flags,

thread_t *new_thread);

int GC_thr_join(thread_t wait_for, thread_t *departed, void **status);

int GC_thr_suspend(thread_t target_thread);

int GC_thr_continue(thread_t target_thread);

void * GC_dlopen(const char *path, int mode);

# ifdef _SOLARIS_PTHREADS

# include <pthread.h>

extern int GC_pthread_create(pthread_t *new_thread,

const pthread_attr_t *attr,

void * (*thread_execp)(void *), void *arg);

extern int GC_pthread_join(pthread_t wait_for, void **status);

# undef thread_t

# define pthread_join GC_pthread_join

# define pthread_create GC_pthread_create

#endif

# define thr_create GC_thr_create

# define thr_join GC_thr_join

# define thr_suspend GC_thr_suspend

# define thr_continue GC_thr_continue

# define dlopen GC_dlopen

# endif /* SOLARIS_THREADS */

#if !defined(USE_LD_WRAP) && \

(defined(IRIX_THREADS) || defined(LINUX_THREADS) || defined(HPUX_THREADS))

/* We treat these similarly. */

# include <pthread.h>

# include <signal.h>

int GC_pthread_create(pthread_t *new_thread,

const pthread_attr_t *attr,

void *(*start_routine)(void *), void *arg);

int GC_pthread_sigmask(int how, const sigset_t *set, sigset_t *oset);

int GC_pthread_join(pthread_t thread, void **retval);

# define pthread_create GC_pthread_create

# define pthread_sigmask GC_pthread_sigmask

# define pthread_join GC_pthread_join

# define dlopen GC_dlopen

#endif /* xxxxx_THREADS */

# if defined(PCR) || defined(SOLARIS_THREADS) || defined(WIN32_THREADS) || \

defined(IRIX_THREADS) || defined(LINUX_THREADS) || \

defined(IRIX_JDK_THREADS) || defined(HPUX_THREADS)

/* Any flavor of threads except SRC_M3. */

/* This returns a list of objects, linked through their first */

/* word. Its use can greatly reduce lock contention problems, since */

/* the allocation lock can be acquired and released many fewer times. */

/* lb must be large enough to hold the pointer field. */

GC_PTR GC_malloc_many(size_t lb);

#define GC_NEXT(p) (*(GC_PTR *)(p)) /* Retrieve the next element */

/* in returned list. */

extern void GC_thr_init(); /* Needed for Solaris/X86 */

#endif /* THREADS && !SRC_M3 */

/*

* If you are planning on putting

* the collector in a SunOS 5 dynamic library, you need to call GC_INIT()

* from the statically loaded program section.

* This circumvents a Solaris 2.X (X<=4) linker bug.

*/

#if defined(sparc) || defined(__sparc)

# define GC_INIT() { extern end, etext; \

GC_noop(&end, &etext); }

#else

# if defined(__CYGWIN32__) && defined(GC_USE_DLL)

/*

* Similarly gnu-win32 DLLs need explicit initialization

*/

# define GC_INIT() { GC_add_roots(DATASTART, DATAEND); }

# else

# define GC_INIT()

# endif

#endif

#if (defined(_MSDOS) || defined(_MSC_VER)) && (_M_IX86 >= 300) \

|| defined(_WIN32)

/* win32S may not free all resources on process exit. */

/* This explicitly deallocates the heap. */

GC_API void GC_win32_free_heap ();

#endif

#ifdef __cplusplus

} /* end of extern "C" */

#endif

#endif /* _GC_H */