michael@0: /*
michael@0:  * Copyright © 2007  Chris Wilson
michael@0:  * Copyright © 2009,2010  Red Hat, Inc.
michael@0:  * Copyright © 2011,2012  Google, Inc.
michael@0:  *
michael@0:  *  This is part of HarfBuzz, a text shaping library.
michael@0:  *
michael@0:  * Permission is hereby granted, without written agreement and without
michael@0:  * license or royalty fees, to use, copy, modify, and distribute this
michael@0:  * software and its documentation for any purpose, provided that the
michael@0:  * above copyright notice and the following two paragraphs appear in
michael@0:  * all copies of this software.
michael@0:  *
michael@0:  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
michael@0:  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
michael@0:  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
michael@0:  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
michael@0:  * DAMAGE.
michael@0:  *
michael@0:  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
michael@0:  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
michael@0:  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
michael@0:  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
michael@0:  *
michael@0:  * Contributor(s):
michael@0:  *	Chris Wilson <chris@chris-wilson.co.uk>
michael@0:  * Red Hat Author(s): Behdad Esfahbod
michael@0:  * Google Author(s): Behdad Esfahbod
michael@0:  */
michael@0: 
michael@0: #ifndef HB_OBJECT_PRIVATE_HH
michael@0: #define HB_OBJECT_PRIVATE_HH
michael@0: 
michael@0: #include "hb-private.hh"
michael@0: 
michael@0: #include "hb-atomic-private.hh"
michael@0: #include "hb-mutex-private.hh"
michael@0: 
michael@0: 
michael@0: /* Debug */
michael@0: 
michael@0: #ifndef HB_DEBUG_OBJECT
michael@0: #define HB_DEBUG_OBJECT (HB_DEBUG+0)
michael@0: #endif
michael@0: 
michael@0: 
michael@0: /* reference_count */
michael@0: 
michael@0: #define HB_REFERENCE_COUNT_INVALID_VALUE ((hb_atomic_int_t) -1)
michael@0: #define HB_REFERENCE_COUNT_INVALID {HB_REFERENCE_COUNT_INVALID_VALUE}
michael@0: struct hb_reference_count_t
michael@0: {
michael@0:   hb_atomic_int_t ref_count;
michael@0: 
michael@0:   inline void init (int v) { ref_count = v; }
michael@0:   inline int inc (void) { return hb_atomic_int_add (const_cast<hb_atomic_int_t &> (ref_count),  1); }
michael@0:   inline int dec (void) { return hb_atomic_int_add (const_cast<hb_atomic_int_t &> (ref_count), -1); }
michael@0:   inline void finish (void) { ref_count = HB_REFERENCE_COUNT_INVALID_VALUE; }
michael@0: 
michael@0:   inline bool is_invalid (void) const { return ref_count == HB_REFERENCE_COUNT_INVALID_VALUE; }
michael@0: 
michael@0: };
michael@0: 
michael@0: 
michael@0: /* user_data */
michael@0: 
michael@0: #define HB_USER_DATA_ARRAY_INIT {HB_MUTEX_INIT, HB_LOCKABLE_SET_INIT}
michael@0: struct hb_user_data_array_t
michael@0: {
michael@0:   /* TODO Add tracing. */
michael@0: 
michael@0:   struct hb_user_data_item_t {
michael@0:     hb_user_data_key_t *key;
michael@0:     void *data;
michael@0:     hb_destroy_func_t destroy;
michael@0: 
michael@0:     inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; }
michael@0:     inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; }
michael@0: 
michael@0:     void finish (void) { if (destroy) destroy (data); }
michael@0:   };
michael@0: 
michael@0:   hb_mutex_t lock;
michael@0:   hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items;
michael@0: 
michael@0:   inline void init (void) { lock.init (); items.init (); }
michael@0: 
michael@0:   HB_INTERNAL bool set (hb_user_data_key_t *key,
michael@0: 			void *              data,
michael@0: 			hb_destroy_func_t   destroy,
michael@0: 			hb_bool_t           replace);
michael@0: 
michael@0:   HB_INTERNAL void *get (hb_user_data_key_t *key);
michael@0: 
michael@0:   inline void finish (void) { items.finish (lock); lock.finish (); }
michael@0: };
michael@0: 
michael@0: 
michael@0: /* object_header */
michael@0: 
michael@0: struct hb_object_header_t
michael@0: {
michael@0:   hb_reference_count_t ref_count;
michael@0:   hb_user_data_array_t user_data;
michael@0: 
michael@0: #define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INVALID, HB_USER_DATA_ARRAY_INIT}
michael@0: 
michael@0:   static inline void *create (unsigned int size) {
michael@0:     hb_object_header_t *obj = (hb_object_header_t *) calloc (1, size);
michael@0: 
michael@0:     if (likely (obj))
michael@0:       obj->init ();
michael@0: 
michael@0:     return obj;
michael@0:   }
michael@0: 
michael@0:   inline void init (void) {
michael@0:     ref_count.init (1);
michael@0:     user_data.init ();
michael@0:   }
michael@0: 
michael@0:   inline bool is_inert (void) const {
michael@0:     return unlikely (ref_count.is_invalid ());
michael@0:   }
michael@0: 
michael@0:   inline void reference (void) {
michael@0:     if (unlikely (!this || this->is_inert ()))
michael@0:       return;
michael@0:     ref_count.inc ();
michael@0:   }
michael@0: 
michael@0:   inline bool destroy (void) {
michael@0:     if (unlikely (!this || this->is_inert ()))
michael@0:       return false;
michael@0:     if (ref_count.dec () != 1)
michael@0:       return false;
michael@0: 
michael@0:     ref_count.finish (); /* Do this before user_data */
michael@0:     user_data.finish ();
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   inline bool set_user_data (hb_user_data_key_t *key,
michael@0: 			     void *              data,
michael@0: 			     hb_destroy_func_t   destroy_func,
michael@0: 			     hb_bool_t           replace) {
michael@0:     if (unlikely (!this || this->is_inert ()))
michael@0:       return false;
michael@0: 
michael@0:     return user_data.set (key, data, destroy_func, replace);
michael@0:   }
michael@0: 
michael@0:   inline void *get_user_data (hb_user_data_key_t *key) {
michael@0:     if (unlikely (!this || this->is_inert ()))
michael@0:       return NULL;
michael@0: 
michael@0:     return user_data.get (key);
michael@0:   }
michael@0: 
michael@0:   inline void trace (const char *function) const {
michael@0:     if (unlikely (!this)) return;
michael@0:     /* TODO We cannot use DEBUG_MSG_FUNC here since that one currently only
michael@0:      * prints the class name and throws away the template info. */
michael@0:     DEBUG_MSG (OBJECT, (void *) this,
michael@0: 	       "%s refcount=%d",
michael@0: 	       function,
michael@0: 	       this ? ref_count.ref_count : 0);
michael@0:   }
michael@0: 
michael@0:   private:
michael@0:   ASSERT_POD ();
michael@0: };
michael@0: 
michael@0: 
michael@0: /* object */
michael@0: 
michael@0: template <typename Type>
michael@0: static inline void hb_object_trace (const Type *obj, const char *function)
michael@0: {
michael@0:   obj->header.trace (function);
michael@0: }
michael@0: template <typename Type>
michael@0: static inline Type *hb_object_create (void)
michael@0: {
michael@0:   Type *obj = (Type *) hb_object_header_t::create (sizeof (Type));
michael@0:   hb_object_trace (obj, HB_FUNC);
michael@0:   return obj;
michael@0: }
michael@0: template <typename Type>
michael@0: static inline bool hb_object_is_inert (const Type *obj)
michael@0: {
michael@0:   return unlikely (obj->header.is_inert ());
michael@0: }
michael@0: template <typename Type>
michael@0: static inline Type *hb_object_reference (Type *obj)
michael@0: {
michael@0:   hb_object_trace (obj, HB_FUNC);
michael@0:   obj->header.reference ();
michael@0:   return obj;
michael@0: }
michael@0: template <typename Type>
michael@0: static inline bool hb_object_destroy (Type *obj)
michael@0: {
michael@0:   hb_object_trace (obj, HB_FUNC);
michael@0:   return obj->header.destroy ();
michael@0: }
michael@0: template <typename Type>
michael@0: static inline bool hb_object_set_user_data (Type               *obj,
michael@0: 					    hb_user_data_key_t *key,
michael@0: 					    void *              data,
michael@0: 					    hb_destroy_func_t   destroy,
michael@0: 					    hb_bool_t           replace)
michael@0: {
michael@0:   return obj->header.set_user_data (key, data, destroy, replace);
michael@0: }
michael@0: 
michael@0: template <typename Type>
michael@0: static inline void *hb_object_get_user_data (Type               *obj,
michael@0: 					     hb_user_data_key_t *key)
michael@0: {
michael@0:   return obj->header.get_user_data (key);
michael@0: }
michael@0: 
michael@0: 
michael@0: #endif /* HB_OBJECT_PRIVATE_HH */