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_INERT_VALUE -1
51 #define HB_REFERENCE_COUNT_POISON_VALUE -0x0000DEAD
52 #define HB_REFERENCE_COUNT_INIT {HB_ATOMIC_INT_INIT(HB_REFERENCE_COUNT_INERT_VALUE)}
53
54 struct hb_reference_count_t
55 {
56 hb_atomic_int_t ref_count;
57
58 inline void init (int v) { ref_count.set_unsafe (v); }
59 inline int get_unsafe (void) const { return ref_count.get_unsafe (); }
60 inline int inc (void) { return ref_count.inc (); }
61 inline int dec (void) { return ref_count.dec (); }
62 inline void finish (void) { ref_count.set_unsafe (HB_REFERENCE_COUNT_POISON_VALUE); }
63
64 inline bool is_inert (void) const { return ref_count.get_unsafe () == HB_REFERENCE_COUNT_INERT_VALUE; }
65 inline bool is_valid (void) const { return ref_count.get_unsafe () > 0; }
66 };
67
68
69 /* user_data */
70
71 #define HB_USER_DATA_ARRAY_INIT {HB_MUTEX_INIT, HB_LOCKABLE_SET_INIT}
72 struct hb_user_data_array_t
73 {
74 struct hb_user_data_item_t {
75 hb_user_data_key_t *key;
76 void *data;
77 hb_destroy_func_t destroy;
78
79 inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; }
80 inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; }
81
82 void finish (void) { if (destroy) destroy (data); }
83 };
84
85 hb_mutex_t lock;
86 hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items;
87
88 inline void init (void) { lock.init (); items.init (); }
89
90 HB_INTERNAL bool set (hb_user_data_key_t *key,
91 void * data,
92 hb_destroy_func_t destroy,
93 hb_bool_t replace);
94
95 HB_INTERNAL void *get (hb_user_data_key_t *key);
96
97 inline void finish (void) { items.finish (lock); lock.finish (); }
98 };
99
100
101 /* object_header */
102
103 struct hb_object_header_t
104 {
105 hb_reference_count_t ref_count;
106 hb_user_data_array_t user_data;
107
108 #define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INIT, HB_USER_DATA_ARRAY_INIT}
109
110 private:
111 ASSERT_POD ();
112 };
113
114
115 /* object */
116
117 template <typename Type>
118 static inline void hb_object_trace (const Type *obj, const char *function)
119 {
120 DEBUG_MSG (OBJECT, (void *) obj,
121 "%s refcount=%d",
122 function,
123 obj ? obj->header.ref_count.get_unsafe () : 0);
124 }
125
126 template <typename Type>
127 static inline Type *hb_object_create (void)
128 {
129 Type *obj = (Type *) calloc (1, sizeof (Type));
130
131 if (unlikely (!obj))
132 return obj;
133
134 hb_object_init (obj);
135 hb_object_trace (obj, HB_FUNC);
136 return obj;
137 }
138 template <typename Type>
139 static inline void hb_object_init (Type *obj)
140 {
141 obj->header.ref_count.init (1);
142 obj->header.user_data.init ();
143 }
144 template <typename Type>
145 static inline bool hb_object_is_inert (const Type *obj)
146 {
147 return unlikely (obj->header.ref_count.is_inert ());
148 }
149 template <typename Type>
150 static inline bool hb_object_is_valid (const Type *obj)
151 {
152 return likely (obj->header.ref_count.is_valid ());
153 }
154 template <typename Type>
155 static inline Type *hb_object_reference (Type *obj)
156 {
157 hb_object_trace (obj, HB_FUNC);
158 if (unlikely (!obj || hb_object_is_inert (obj)))
159 return obj;
160 assert (hb_object_is_valid (obj));
161 obj->header.ref_count.inc ();
162 return obj;
163 }
164 template <typename Type>
165 static inline bool hb_object_destroy (Type *obj)
166 {
167 hb_object_trace (obj, HB_FUNC);
168 if (unlikely (!obj || hb_object_is_inert (obj)))
169 return false;
170 assert (hb_object_is_valid (obj));
171 if (obj->header.ref_count.dec () != 1)
172 return false;
173
174 obj->header.ref_count.finish (); /* Do this before user_data */
175 obj->header.user_data.finish ();
176 return true;
177 }
178 template <typename Type>
179 static inline bool hb_object_set_user_data (Type *obj,
180 hb_user_data_key_t *key,
181 void * data,
182 hb_destroy_func_t destroy,
183 hb_bool_t replace)
184 {
185 if (unlikely (!obj || hb_object_is_inert (obj)))
186 return false;
187 assert (hb_object_is_valid (obj));
188 return obj->header.user_data.set (key, data, destroy, replace);
189 }
190
191 template <typename Type>
192 static inline void *hb_object_get_user_data (Type *obj,
193 hb_user_data_key_t *key)
194 {
195 if (unlikely (!obj || hb_object_is_inert (obj)))
196 return NULL;
197 assert (hb_object_is_valid (obj));
198 return obj->header.user_data.get (key);
199 }
200
201
202 #endif /* HB_OBJECT_PRIVATE_HH */