|  | /* Macros for general registry objects. | 
|  |  | 
|  | Copyright (C) 2011-2022 Free Software Foundation, Inc. | 
|  |  | 
|  | This file is part of GDB. | 
|  |  | 
|  | This program is free software; you can redistribute it and/or modify | 
|  | it under the terms of the GNU General Public License as published by | 
|  | the Free Software Foundation; either version 3 of the License, or | 
|  | (at your option) any later version. | 
|  |  | 
|  | This program is distributed in the hope that it will be useful, | 
|  | but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | GNU General Public License for more details. | 
|  |  | 
|  | You should have received a copy of the GNU General Public License | 
|  | along with this program.  If not, see <http://www.gnu.org/licenses/>.  */ | 
|  |  | 
|  | #ifndef REGISTRY_H | 
|  | #define REGISTRY_H | 
|  |  | 
|  | #include <type_traits> | 
|  |  | 
|  | /* The macros here implement a template type and functions for | 
|  | associating some user data with a container object. | 
|  |  | 
|  | A registry is associated with a struct tag name.  To attach a | 
|  | registry to a structure, use DEFINE_REGISTRY.  This takes the | 
|  | structure tag and an access method as arguments.  In the usual | 
|  | case, where the registry fields appear directly in the struct, you | 
|  | can use the 'REGISTRY_FIELDS' macro to declare the fields in the | 
|  | struct definition, and you can pass 'REGISTRY_ACCESS_FIELD' as the | 
|  | access argument to DEFINE_REGISTRY.  In other cases, use | 
|  | REGISTRY_FIELDS to define the fields in the appropriate spot, and | 
|  | then define your own accessor to find the registry field structure | 
|  | given an instance of your type. | 
|  |  | 
|  | The API user requests a key from a registry during gdb | 
|  | initialization.  Later this key can be used to associate some | 
|  | module-specific data with a specific container object. | 
|  |  | 
|  | The exported API is best used via the wrapper macros: | 
|  |  | 
|  | - register_TAG_data(TAG) | 
|  | Get a new key for the container type TAG. | 
|  |  | 
|  | - register_TAG_data_with_cleanup(TAG, SAVE, FREE) | 
|  | Get a new key for the container type TAG. | 
|  | SAVE and FREE are defined as void (*) (struct TAG *object, void *data) | 
|  | When the container object OBJECT is destroyed, first all registered SAVE | 
|  | functions are called. | 
|  | Then all FREE functions are called. | 
|  | Either or both may be NULL.  DATA is the data associated with the | 
|  | container object OBJECT. | 
|  |  | 
|  | - clear_TAG_data(TAG, OBJECT) | 
|  | Clear all the data associated with OBJECT.  Should be called by the | 
|  | container implementation when a container object is destroyed. | 
|  |  | 
|  | - set_TAG_data(TAG, OBJECT, KEY, DATA) | 
|  | Set the data on an object. | 
|  |  | 
|  | - TAG_data(TAG, OBJECT, KEY) | 
|  | Fetch the data for an object; returns NULL if it has not been set. | 
|  | */ | 
|  |  | 
|  | /* This structure is used in a container to hold the data that the | 
|  | registry uses.  */ | 
|  |  | 
|  | struct registry_fields | 
|  | { | 
|  | void **data; | 
|  | unsigned num_data; | 
|  | }; | 
|  |  | 
|  | /* This macro is used in a container struct definition to define the | 
|  | fields used by the registry code.  */ | 
|  |  | 
|  | #define REGISTRY_FIELDS				\ | 
|  | struct registry_fields registry_data | 
|  |  | 
|  | /* A convenience macro for the typical case where the registry data is | 
|  | kept as fields of the object.  This can be passed as the ACCESS | 
|  | method to DEFINE_REGISTRY.  */ | 
|  |  | 
|  | #define REGISTRY_ACCESS_FIELD(CONTAINER) \ | 
|  | (CONTAINER) | 
|  |  | 
|  | /* Opaque type representing a container type with a registry.  This | 
|  | type is never defined.  This is used to factor out common | 
|  | functionality of all struct tag names into common code.  IOW, | 
|  | "struct tag name" pointers are cast to and from "struct | 
|  | registry_container" pointers when calling the common registry | 
|  | "backend" functions.  */ | 
|  | struct registry_container; | 
|  |  | 
|  | /* Registry callbacks have this type.  */ | 
|  | typedef void (*registry_data_callback) (struct registry_container *, void *); | 
|  |  | 
|  | struct registry_data | 
|  | { | 
|  | unsigned index; | 
|  | registry_data_callback save; | 
|  | registry_data_callback free; | 
|  | }; | 
|  |  | 
|  | struct registry_data_registration | 
|  | { | 
|  | struct registry_data *data; | 
|  | struct registry_data_registration *next; | 
|  | }; | 
|  |  | 
|  | struct registry_data_registry | 
|  | { | 
|  | struct registry_data_registration *registrations; | 
|  | unsigned num_registrations; | 
|  | }; | 
|  |  | 
|  | /* Registry backend functions.  Client code uses the frontend | 
|  | functions defined by DEFINE_REGISTRY below instead.  */ | 
|  |  | 
|  | const struct registry_data *register_data_with_cleanup | 
|  | (struct registry_data_registry *registry, | 
|  | registry_data_callback save, | 
|  | registry_data_callback free); | 
|  |  | 
|  | void registry_alloc_data (struct registry_data_registry *registry, | 
|  | struct registry_fields *registry_fields); | 
|  |  | 
|  | /* Cast FUNC and CONTAINER to the real types, and call FUNC, also | 
|  | passing DATA.  */ | 
|  | typedef void (*registry_callback_adaptor) (registry_data_callback func, | 
|  | struct registry_container *container, | 
|  | void *data); | 
|  |  | 
|  | void registry_clear_data (struct registry_data_registry *data_registry, | 
|  | registry_callback_adaptor adaptor, | 
|  | struct registry_container *container, | 
|  | struct registry_fields *fields); | 
|  |  | 
|  | void registry_container_free_data (struct registry_data_registry *data_registry, | 
|  | registry_callback_adaptor adaptor, | 
|  | struct registry_container *container, | 
|  | struct registry_fields *fields); | 
|  |  | 
|  | void registry_set_data (struct registry_fields *fields, | 
|  | const struct registry_data *data, | 
|  | void *value); | 
|  |  | 
|  | void *registry_data (struct registry_fields *fields, | 
|  | const struct registry_data *data); | 
|  |  | 
|  | /* Define a new registry implementation.  */ | 
|  |  | 
|  | #define DEFINE_REGISTRY(TAG, ACCESS)					\ | 
|  | static struct registry_data_registry TAG ## _data_registry = { NULL, 0 }; \ | 
|  | \ | 
|  | const struct TAG ## _data *						\ | 
|  | register_ ## TAG ## _data_with_cleanup (void (*save) (struct TAG *, void *), \ | 
|  | void (*free) (struct TAG *, void *)) \ | 
|  | {									\ | 
|  | return (struct TAG ## _data *)					\ | 
|  | register_data_with_cleanup (&TAG ## _data_registry,			\ | 
|  | (registry_data_callback) save,		\ | 
|  | (registry_data_callback) free);		\ | 
|  | }									\ | 
|  | \ | 
|  | const struct TAG ## _data *						\ | 
|  | register_ ## TAG ## _data (void)					\ | 
|  | {									\ | 
|  | return register_ ## TAG ## _data_with_cleanup (NULL, NULL);		\ | 
|  | }									\ | 
|  | \ | 
|  | static void								\ | 
|  | TAG ## _alloc_data (struct TAG *container)				\ | 
|  | {									\ | 
|  | struct registry_fields *rdata = &ACCESS (container)->registry_data;	\ | 
|  | \ | 
|  | registry_alloc_data (&TAG ## _data_registry, rdata);			\ | 
|  | }									\ | 
|  | \ | 
|  | static void								\ | 
|  | TAG ## registry_callback_adaptor (registry_data_callback func,		\ | 
|  | struct registry_container *container, \ | 
|  | void *data)				\ | 
|  | {									\ | 
|  | struct TAG *tagged_container = (struct TAG *) container;		\ | 
|  | \ | 
|  | registry_ ## TAG ## _callback tagged_func				\ | 
|  | = (registry_ ## TAG ## _callback) func;				\ | 
|  | \ | 
|  | tagged_func (tagged_container, data);					\ | 
|  | }									\ | 
|  | \ | 
|  | void									\ | 
|  | clear_ ## TAG ## _data (struct TAG *container)				\ | 
|  | {									\ | 
|  | struct registry_fields *rdata = &ACCESS (container)->registry_data;	\ | 
|  | \ | 
|  | registry_clear_data (&TAG ## _data_registry,				\ | 
|  | TAG ## registry_callback_adaptor,		\ | 
|  | (struct registry_container *) container,		\ | 
|  | rdata);						\ | 
|  | }									\ | 
|  | \ | 
|  | static void								\ | 
|  | TAG ## _free_data (struct TAG *container)				\ | 
|  | {									\ | 
|  | struct registry_fields *rdata = &ACCESS (container)->registry_data;	\ | 
|  | \ | 
|  | registry_container_free_data (&TAG ## _data_registry,			\ | 
|  | TAG ## registry_callback_adaptor,	\ | 
|  | (struct registry_container *) container, \ | 
|  | rdata);					\ | 
|  | }									\ | 
|  | \ | 
|  | void									\ | 
|  | set_ ## TAG ## _data (struct TAG *container,				\ | 
|  | const struct TAG ## _data *data,			\ | 
|  | void *value)					\ | 
|  | {									\ | 
|  | struct registry_fields *rdata = &ACCESS (container)->registry_data;	\ | 
|  | \ | 
|  | registry_set_data (rdata,						\ | 
|  | (struct registry_data *) data,			\ | 
|  | value);						\ | 
|  | }									\ | 
|  | \ | 
|  | void *									\ | 
|  | TAG ## _data (struct TAG *container, const struct TAG ## _data *data)	\ | 
|  | {									\ | 
|  | struct registry_fields *rdata = &ACCESS (container)->registry_data;	\ | 
|  | \ | 
|  | return registry_data (rdata,						\ | 
|  | (struct registry_data *) data);			\ | 
|  | } | 
|  |  | 
|  |  | 
|  | /* External declarations for the registry functions.  */ | 
|  |  | 
|  | #define DECLARE_REGISTRY(TAG)						\ | 
|  | struct TAG ## _data;							\ | 
|  | typedef void (*registry_ ## TAG ## _callback) (struct TAG *, void *);	\ | 
|  | extern const struct TAG ## _data *register_ ## TAG ## _data (void);	\ | 
|  | extern const struct TAG ## _data *register_ ## TAG ## _data_with_cleanup \ | 
|  | (registry_ ## TAG ## _callback save, registry_ ## TAG ## _callback free); \ | 
|  | extern void clear_ ## TAG ## _data (struct TAG *);			\ | 
|  | extern void set_ ## TAG ## _data (struct TAG *,				\ | 
|  | const struct TAG ## _data *data,	\ | 
|  | void *value);				\ | 
|  | extern void *TAG ## _data (struct TAG *,				\ | 
|  | const struct TAG ## _data *data);		\ | 
|  | \ | 
|  | template<typename DATA, typename Deleter = std::default_delete<DATA>>	\ | 
|  | class TAG ## _key							\ | 
|  | {									\ | 
|  | public:									\ | 
|  | \ | 
|  | TAG ## _key ()							\ | 
|  | : m_key (register_ ## TAG ## _data_with_cleanup (nullptr,		\ | 
|  | cleanup))		\ | 
|  | {									\ | 
|  | }									\ | 
|  | \ | 
|  | DATA *get (struct TAG *obj) const					\ | 
|  | {									\ | 
|  | return (DATA *) TAG ## _data (obj, m_key);				\ | 
|  | }									\ | 
|  | \ | 
|  | void set (struct TAG *obj, DATA *data) const				\ | 
|  | {									\ | 
|  | set_ ## TAG ## _data (obj, m_key, data);				\ | 
|  | }									\ | 
|  | \ | 
|  | template<typename Dummy = DATA *, typename... Args>			\ | 
|  | typename std::enable_if<std::is_same<Deleter,				\ | 
|  | std::default_delete<DATA>>::value, \ | 
|  | Dummy>::type					\ | 
|  | emplace (struct TAG *obj, Args &&...args) const			\ | 
|  | {									\ | 
|  | DATA *result = new DATA (std::forward<Args> (args)...);		\ | 
|  | set (obj, result);							\ | 
|  | return result;							\ | 
|  | }									\ | 
|  | \ | 
|  | void clear (struct TAG *obj) const					\ | 
|  | {									\ | 
|  | DATA *datum = get (obj);						\ | 
|  | if (datum != nullptr)						\ | 
|  | {									\ | 
|  | cleanup (obj, datum);						\ | 
|  | set (obj, nullptr);						\ | 
|  | }									\ | 
|  | }									\ | 
|  | \ | 
|  | private:								\ | 
|  | \ | 
|  | static void cleanup (struct TAG *obj, void *arg)			\ | 
|  | {									\ | 
|  | DATA *datum = (DATA *) arg;						\ | 
|  | Deleter d;								\ | 
|  | d (datum);								\ | 
|  | }									\ | 
|  | \ | 
|  | const struct TAG ## _data *m_key;					\ | 
|  | }; | 
|  |  | 
|  | #endif /* REGISTRY_H */ |