--- /dev/null
+/*
+ * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
+ * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
+ * Copyright 1996 by Silicon Graphics. 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(_MSC_VER) && defined(_DLL)
+#ifdef GC_BUILD
+#define GC_API __declspec(dllexport)
+#else
+#define GC_API __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;
+# else
+# define GC_PROTO(args) ()
+ typedef char * GC_PTR;
+# 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_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_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_full_freq; /* Number of partial collections between */
+ /* full collections. Matters only if */
+ /* GC_incremental is set. */
+
+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. */
+
+
+/* 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. */
+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 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, char * descr_string, int descr_int
+#else
+# define GC_EXTRAS __FILE__, __LINE__
+# define GC_EXTRA_PARAMS char * descr_string, int descr_int
+#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_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_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));
+
+/* 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));
+
+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 */
+ /* FINALIZE_ON_DEMAND is defined, 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));
+
+#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(IRIX_THREADS) || defined(LINUX_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
+
+#endif /* IRIX_THREADS || LINUX_THREADS */
+
+#if defined(THREADS) && !defined(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. */
+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
+
+#ifdef __cplusplus
+ } /* end of extern "C" */
+#endif
+
+#endif /* _GC_H */
OSDN Git Service
