diff options
Diffstat (limited to 'include/ruby/internal/intern/gc.h')
| -rw-r--r-- | include/ruby/internal/intern/gc.h | 390 |
1 files changed, 0 insertions, 390 deletions
diff --git a/include/ruby/internal/intern/gc.h b/include/ruby/internal/intern/gc.h deleted file mode 100644 index 1617a7cef6..0000000000 --- a/include/ruby/internal/intern/gc.h +++ /dev/null @@ -1,390 +0,0 @@ -#ifndef RBIMPL_INTERN_GC_H /*-*-C++-*-vi:se ft=cpp:*/ -#define RBIMPL_INTERN_GC_H -/** - * @file - * @author Ruby developers <ruby-core@ruby-lang.org> - * @copyright This file is a part of the programming language Ruby. - * Permission is hereby granted, to either redistribute and/or - * modify this file, provided that the conditions mentioned in the - * file COPYING are met. Consult the file for details. - * @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are - * implementation details. Don't take them as canon. They could - * rapidly appear then vanish. The name (path) of this header file - * is also an implementation detail. Do not expect it to persist - * at the place it is now. Developers are free to move it anywhere - * anytime at will. - * @note To ruby-core: remember that this header can be possibly - * recursively included from extension libraries written in C++. - * Do not expect for instance `__VA_ARGS__` is always available. - * We assume C99 for ruby itself but we don't assume languages of - * extension libraries. They could be written in C++98. - * @brief Public APIs related to ::rb_mGC. - */ -#include "ruby/internal/config.h" - -#ifdef STDC_HEADERS -# include <stddef.h> /* size_t */ -#endif - -#if HAVE_SYS_TYPES_H -# include <sys/types.h> /* ssize_t */ -#endif - -#include "ruby/internal/attr/cold.h" -#include "ruby/internal/attr/noreturn.h" -#include "ruby/internal/attr/nonnull.h" -#include "ruby/internal/attr/pure.h" -#include "ruby/internal/dllexport.h" -#include "ruby/internal/value.h" - -RBIMPL_SYMBOL_EXPORT_BEGIN() - -/* gc.c */ - -RBIMPL_ATTR_COLD() -RBIMPL_ATTR_NORETURN() -/** - * Triggers out-of-memory error. If possible it raises ::rb_eNoMemError. But - * because we are running out of memory that is not always doable. This - * function tries hard to show something, but ultimately can die silently. - * - * @exception rb_eNoMemError Raises it if possible. - */ -void rb_memerror(void); - -RBIMPL_ATTR_PURE() -/** - * Queries if the GC is busy. - * - * @retval 0 It isn't. - * @retval 1 It is. - */ -int rb_during_gc(void); - -RBIMPL_ATTR_NONNULL((1)) -/** - * Marks objects between the two pointers. This is one of the GC utility - * functions that you can call when you design your own - * ::rb_data_type_struct::dmark. - * - * @pre Continuous memory region from `start` to `end` shall be fully - * addressable. - * @param[out] start Pointer to an array of objects. - * @param[out] end Pointer that terminates the array of objects. - * @post Objects from `start` to `end`, both inclusive, are marked. - * - * @internal - * - * `end` can be NULL... But that just results in no-op. - */ -void rb_gc_mark_locations(const VALUE *start, const VALUE *end); - -/** - * Identical to rb_mark_hash(), except it marks only values of the table and - * leave their associated keys unmarked. This is one of the GC utility - * functions that you can call when you design your own - * ::rb_data_type_struct::dmark. - * - * @warning Of course it can break GC. Leave it unused if unsure. - * @param[in] tbl A table to mark. - * @post Values stored in `tbl` are marked. - */ -void rb_mark_tbl(struct st_table *tbl); - -/** - * Identical to rb_mark_tbl(), except it marks objects using - * rb_gc_mark_movable(). This is one of the GC utility functions that you can - * call when you design your own ::rb_data_type_struct::dmark. - * - * @warning Of course it can break GC. Leave it unused if unsure. - * @param[in] tbl A table to mark. - * @post Values stored in `tbl` are marked. - */ -void rb_mark_tbl_no_pin(struct st_table *tbl); - -/** - * Identical to rb_mark_hash(), except it marks only keys of the table and - * leave their associated values unmarked. This is one of the GC utility - * functions that you can call when you design your own - * ::rb_data_type_struct::dmark. - * - * @warning Of course it can break GC. Leave it unused if unsure. - * @param[in] tbl A table to mark. - * @post Keys stored in `tbl` are marked. - */ -void rb_mark_set(struct st_table *tbl); - -/** - * Marks keys and values associated inside of the given table. This is one of - * the GC utility functions that you can call when you design your own - * ::rb_data_type_struct::dmark. - * - * @param[in] tbl A table to mark. - * @post Objects stored in `tbl` are marked. - */ -void rb_mark_hash(struct st_table *tbl); - -/** - * Updates references inside of tables. After you marked values using - * rb_mark_tbl_no_pin(), the objects inside of the table could of course be - * moved. This function is to fixup those references. You can call this from - * your ::rb_data_type_struct::dcompact. - * - * @param[out] ptr A table that potentially includes moved references. - * @post Moved references, if any, are corrected. - */ -void rb_gc_update_tbl_refs(st_table *ptr); - -/** - * Identical to rb_gc_mark(), except it allows the passed value be a - * non-object. For instance pointers to different type of memory regions are - * allowed here. Such values are silently ignored. This is one of the GC - * utility functions that you can call when you design your own - * ::rb_data_type_struct::dmark. - * - * @param[out] obj A possible object. - * @post `obj` is marked, if possible. - */ -void rb_gc_mark_maybe(VALUE obj); - -/** - * Marks an object. This is one of the GC utility functions that you can call - * when you design your own ::rb_data_type_struct::dmark. - * - * @param[out] obj Arbitrary Ruby object. - * @post `obj` is marked. - */ -void rb_gc_mark(VALUE obj); - -/** - * Maybe this is the only function provided for C extensions to control the - * pinning of objects, so let us describe it in detail. These days Ruby's GC - * is copying. As far as an object's physical address is guaranteed unused, it - * can move around the object space. Our GC engine rearranges these objects - * after it reclaims unreachable objects from our object space, so that the - * space is compact (improves memory locality). This is called the - * "compaction" phase, and works well most of the time... as far as there are - * no C extensions. C extensions complicate the scenario because Ruby core - * cannot detect any use of the physical address of an object inside of C - * functions. In order to prevent memory corruptions, objects observable from - * C extensions are "pinned"; they stick to where they are born until they die, - * just in case any C extensions touch their raw pointers. This variant of - * scheme is called "Mostly-Copying" garbage collector. Authors of C - * extensions, however, can extremely carefully write them to become - * compaction-aware. To do so avoid referring to a Ruby object from inside of - * your struct in the first place. But if that is not possible, use this - * function from your ::rb_data_type_struct::dmark then. This way objects - * marked using it are considered movable. If you chose this way you have to - * manually fix up locations of such moved pointers using rb_gc_location(). - * - * @see Bartlett, Joel F., "Compacting Garbage Collection with Ambiguous - * Roots", ACM SIGPLAN Lisp Pointers Volume 1 Issue 6 pp. 3-12, - * April-May-June, 1988. https://doi.org/10.1145/1317224.1317225 - * - * @param[in] obj Object that is movable. - * @post Values stored in `tbl` are marked. - */ -void rb_gc_mark_movable(VALUE obj); - -/** - * Finds a new "location" of an object. An object can be moved on compaction. - * This function projects its new abode, or just returns the passed object if - * not moved. This is one of the GC utility functions that you can call when - * you design your own ::rb_data_type_struct::dcompact. - * - * @param[in] obj An object, possibly already moved to somewhere else. - * @return An object, which holds the current contents of former `obj`. - */ -VALUE rb_gc_location(VALUE obj); - -/** - * Asserts that the passed object is no longer needed. Such objects are - * reclaimed sooner or later so this function is not mandatory. But sometimes - * you can know from your application knowledge that an object is surely dead - * at some point. Calling this as a hint can be a polite way. - * - * @param[out] obj Object, dead. - * @pre `obj` have never been passed to this function before. - * @post `obj` could be invalidated. - * @warning It is a failure to pass an object multiple times to this - * function. - */ -void rb_gc_force_recycle(VALUE obj); - -/** - * Triggers a GC process. This was the only GC entry point that we had at the - * beginning. Over time our GC evolved. Now what this function does is just a - * very simplified variation of the entire GC algorithms. A series of - * procedures kicked by this API is called a "full" GC. - * - * - It immediately scans the entire object space to sort the dead. - * - It immediately reclaims any single dead bodies to reuse later. - * - * It is worth noting that the procedures above do not include evaluations of - * finalisers. They run later. - * - * @internal - * - * Finalisers are deferred until we can handle interrupts. See - * `rb_postponed_job_flush` in vm_trace.c. - * - * Of course there are GC that are not "full". For instance this one and the - * GC which runs when we are running out of memory are different. See - * `gc_profile_record_flag` defined in gc.c for the kinds of GC. - * - * In spite of the name this is not what everything that a GC can trigger. As - * of writing it seems this function does not trigger compaction. But this - * might change in future. - */ -void rb_gc(void); - -/** - * Copy&paste an object's finaliser to another. This is one of the GC utility - * functions that you can call when you design your own `initialize_copy`, - * `initialize_dup`, `initialize_clone`. - * - * @param[out] dst Destination object. - * @param[in] src Source object. - * @post `dst` and `src` share the same finaliser. - * - * @internal - * - * But isn't it easier for you to call super, and let `Object#intialize_copy` - * call this function instead? - */ -void rb_gc_copy_finalizer(VALUE dst, VALUE src); - -/** - * (Re-) enables GC. This makes sense only after you called rb_gc_disable(). - * - * @retval RUBY_Qtrue GC was disabled before. - * @retval RUBY_Qfalse GC was enabled before. - * @post GC is enabled. - * - * @internal - * - * This is one of such exceptional functions that does not raise both Ruby - * exceptions and C++ exceptions. - */ -VALUE rb_gc_enable(void); - -/** - * Disables GC. This prevents automatic GC runs when the process is running - * out of memory. Such situations shall result in rb_memerror(). However this - * does not prevent users from manually invoking rb_gc(). That should work. - * People abused this by disabling GC at the beginning of an event loop, - * process events without GC overheads, then manually force reclaiming garbage - * at the bottom of the loop. However because our GC is now much smarter than - * just calling rb_gc(), this technique is proven to be sub-optimal these days. - * It is believed that there is currently practically no needs of this - * function. - * - * @retval RUBY_Qtrue GC was disabled before. - * @retval RUBY_Qfalse GC was enabled before. - * @post GC is disabled. - */ -VALUE rb_gc_disable(void); - -/** - * Identical to rb_gc(), except the return value. - * - * @return Always returns ::RUBY_Qnil. - */ -VALUE rb_gc_start(void); - -/** - * Assigns a finaliser for an object. Each objects can have objects (typically - * blocks) that run immediately after that object dies. They are called - * finalisers of an object. This function associates a finaliser object with a - * target object. - * - * @note Note that finalisers run _after_ the object they finalise dies. You - * cannot for instance call its methods. - * @note If your finaliser references the object it finalises that object - * loses any chance to become a garbage; effectively leaks memory until - * the end of the process. - * - * @param[in] obj Target to finalise. - * @param[in] block Something `call`able. - * @exception rb_eRuntimeError Somehow `obj` cannot have finalisers. - * @exception rb_eFrozenError `obj` is frozen. - * @exception rb_eArgError `block` doesn't respond to `call`. - * @return The passed `block`. - * @post `block` runs after `obj` dies. - */ -VALUE rb_define_finalizer(VALUE obj, VALUE block); - -/** - * Modifies the object so that it has no finalisers at all. This function is - * mainly provided for symmetry. No practical usages can be thought of. - * - * @param[out] obj Object to clear its finalisers. - * @exception rb_eFrozenError `obj` is frozen. - * @return The passed `obj`. - * @post `obj` has no finalisers. - * @note There is no way to undefine a specific part of many finalisers - * that `obj` could have. All you can do is to clear them all. - */ -VALUE rb_undefine_finalizer(VALUE obj); - -/** - * Identical to rb_gc_stat(), with "count" parameter. - * - * @return Lifetime total number of runs of GC. - */ -size_t rb_gc_count(void); - -/** - * Obtains various GC related profiles. The parameter can be either a Symbol - * or a Hash. If a Hash is passed, it is filled with everything currently - * available. If a Symbol is passed just that portion is returned. - * - * Possible variations of keys you can pass here change from version to - * version. You can get the list of known keys by passing an empty hash and - * let it be filled. - * - * @param[in,out] key_or_buf A Symbol, or a Hash. - * @exception rb_eTypeError Neither Symbol nor Hash. - * @exception rb_eFrozenError Frozen hash is passed. - * @return In case a Hash is passed it returns 0. Otherwise the - * profile value associated with the given key is returned. - * @post In case a Hash is passed it is filled with values. - */ -size_t rb_gc_stat(VALUE key_or_buf); - -/** - * Obtains various info regarding the most recent GC run. This includes for - * instance the reason of the GC. The parameter can be either a Symbol or a - * Hash. If a Hash is passed, it is filled with everything currently - * available. If a Symbol is passed just that portion is returned. - * - * Possible variations of keys you can pass here change from version to - * version. You can get the list of known keys by passing an empty hash and - * let it be filled. - * - * @param[in,out] key_or_buf A Symbol, or a Hash. - * @exception rb_eTypeError Neither Symbol nor Hash. - * @exception rb_eFrozenError Frozen hash is passed. - * @return In case a Hash is passed it returns that hash. Otherwise - * the profile value associated with the given key is returned. - * @post In case a Hash is passed it is filled with values. - */ -VALUE rb_gc_latest_gc_info(VALUE key_or_buf); - -/** - * Informs that there are external memory usages. Our GC runs when we are - * running out of memory. The amount of memory, however, can increase/decrease - * behind-the-scene. For instance DLLs can allocate memories using `mmap(2)` - * etc, which are opaque to us. Registering such external allocations using - * this function enables proper detection of how much memories an object used - * as a whole. That will trigger GCs more often than it would otherwise. You - * can also pass negative numbers here, to indicate that such external - * allocations are gone. - * - * @param[in] diff Amount of memory increased(+)/decreased(-). - */ -void rb_gc_adjust_memory_usage(ssize_t diff); - -RBIMPL_SYMBOL_EXPORT_END() - -#endif /* RBIMPL_INTERN_GC_H */ |