hb-object-private.hh revision 7babfe5a7904c26060c5b8441ca1bf23e1444f35 
1/*
2 * Copyright © 2007  Chris Wilson
3 * Copyright © 2009,2010  Red Hat, Inc.
4 * Copyright © 2011,2012  Google, Inc.
5 *
6 *  This is part of HarfBuzz, a text shaping library.
7 *
8 * Permission is hereby granted, without written agreement and without
9 * license or royalty fees, to use, copy, modify, and distribute this
10 * software and its documentation for any purpose, provided that the
11 * above copyright notice and the following two paragraphs appear in
12 * all copies of this software.
13 *
14 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
15 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
17 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
18 * DAMAGE.
19 *
20 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
21 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
22 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
23 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
24 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
25 *
26 * Contributor(s):
27 *	Chris Wilson <chris@chris-wilson.co.uk>
28 * Red Hat Author(s): Behdad Esfahbod
29 * Google Author(s): Behdad Esfahbod
30 */
31
32#ifndef HB_OBJECT_PRIVATE_HH
33#define HB_OBJECT_PRIVATE_HH
34
35#include "hb-private.hh"
36
37#include "hb-atomic-private.hh"
38#include "hb-mutex-private.hh"
39
40
41/* Debug */
42
43#ifndef HB_DEBUG_OBJECT
44#define HB_DEBUG_OBJECT (HB_DEBUG+0)
45#endif
46
47
48/* reference_count */
49
50#define HB_REFERENCE_COUNT_INVALID_VALUE ((hb_atomic_int_t) -1)
51#define HB_REFERENCE_COUNT_INVALID {HB_REFERENCE_COUNT_INVALID_VALUE}
52struct hb_reference_count_t
53{
54  hb_atomic_int_t ref_count;
55
56  inline void init (int v) { ref_count = v; }
57  inline int inc (void) { return hb_atomic_int_add (const_cast<hb_atomic_int_t &> (ref_count),  1); }
58  inline int dec (void) { return hb_atomic_int_add (const_cast<hb_atomic_int_t &> (ref_count), -1); }
59  inline void finish (void) { ref_count = HB_REFERENCE_COUNT_INVALID_VALUE; }
60
61  inline bool is_invalid (void) const { return ref_count == HB_REFERENCE_COUNT_INVALID_VALUE; }
62
63};
64
65
66/* user_data */
67
68#define HB_USER_DATA_ARRAY_INIT {HB_MUTEX_INIT, HB_LOCKABLE_SET_INIT}
69struct hb_user_data_array_t
70{
71  /* TODO Add tracing. */
72
73  struct hb_user_data_item_t {
74    hb_user_data_key_t *key;
75    void *data;
76    hb_destroy_func_t destroy;
77
78    inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; }
79    inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; }
80
81    void finish (void) { if (destroy) destroy (data); }
82  };
83
84  hb_mutex_t lock;
85  hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items;
86
87  inline void init (void) { lock.init (); items.init (); }
88
89  HB_INTERNAL bool set (hb_user_data_key_t *key,
90			void *              data,
91			hb_destroy_func_t   destroy,
92			hb_bool_t           replace);
93
94  HB_INTERNAL void *get (hb_user_data_key_t *key);
95
96  inline void finish (void) { items.finish (lock); lock.finish (); }
97};
98
99
100/* object_header */
101
102struct hb_object_header_t
103{
104  hb_reference_count_t ref_count;
105  hb_user_data_array_t user_data;
106
107#define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INVALID, HB_USER_DATA_ARRAY_INIT}
108
109  static inline void *create (unsigned int size) {
110    hb_object_header_t *obj = (hb_object_header_t *) calloc (1, size);
111
112    if (likely (obj))
113      obj->init ();
114
115    return obj;
116  }
117
118  inline void init (void) {
119    ref_count.init (1);
120    user_data.init ();
121  }
122
123  inline bool is_inert (void) const {
124    return unlikely (ref_count.is_invalid ());
125  }
126
127  inline void reference (void) {
128    if (unlikely (!this || this->is_inert ()))
129      return;
130    ref_count.inc ();
131  }
132
133  inline bool destroy (void) {
134    if (unlikely (!this || this->is_inert ()))
135      return false;
136    if (ref_count.dec () != 1)
137      return false;
138
139    ref_count.finish (); /* Do this before user_data */
140    user_data.finish ();
141
142    return true;
143  }
144
145  inline bool set_user_data (hb_user_data_key_t *key,
146			     void *              data,
147			     hb_destroy_func_t   destroy_func,
148			     hb_bool_t           replace) {
149    if (unlikely (!this || this->is_inert ()))
150      return false;
151
152    return user_data.set (key, data, destroy_func, replace);
153  }
154
155  inline void *get_user_data (hb_user_data_key_t *key) {
156    if (unlikely (!this || this->is_inert ()))
157      return NULL;
158
159    return user_data.get (key);
160  }
161
162  inline void trace (const char *function) const {
163    if (unlikely (!this)) return;
164    /* TODO We cannot use DEBUG_MSG_FUNC here since that one currently only
165     * prints the class name and throws away the template info. */
166    DEBUG_MSG (OBJECT, (void *) this,
167	       "%s refcount=%d",
168	       function,
169	       this ? ref_count.ref_count : 0);
170  }
171
172  private:
173  ASSERT_POD ();
174};
175
176
177/* object */
178
179template <typename Type>
180static inline void hb_object_trace (const Type *obj, const char *function)
181{
182  obj->header.trace (function);
183}
184template <typename Type>
185static inline Type *hb_object_create (void)
186{
187  Type *obj = (Type *) hb_object_header_t::create (sizeof (Type));
188  hb_object_trace (obj, HB_FUNC);
189  return obj;
190}
191template <typename Type>
192static inline bool hb_object_is_inert (const Type *obj)
193{
194  return unlikely (obj->header.is_inert ());
195}
196template <typename Type>
197static inline Type *hb_object_reference (Type *obj)
198{
199  hb_object_trace (obj, HB_FUNC);
200  obj->header.reference ();
201  return obj;
202}
203template <typename Type>
204static inline bool hb_object_destroy (Type *obj)
205{
206  hb_object_trace (obj, HB_FUNC);
207  return obj->header.destroy ();
208}
209template <typename Type>
210static inline bool hb_object_set_user_data (Type               *obj,
211					    hb_user_data_key_t *key,
212					    void *              data,
213					    hb_destroy_func_t   destroy,
214					    hb_bool_t           replace)
215{
216  return obj->header.set_user_data (key, data, destroy, replace);
217}
218
219template <typename Type>
220static inline void *hb_object_get_user_data (Type               *obj,
221					     hb_user_data_key_t *key)
222{
223  return obj->header.get_user_data (key);
224}
225
226
227#endif /* HB_OBJECT_PRIVATE_HH */
228