1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 // This file is available under and governed by the GNU General Public
26 // License version 2 only, as published by the Free Software Foundation.
27 // However, the following notice accompanied the original version of this
28 // file:
29 //
30 /*
31 * Copyright © 2007 Chris Wilson
32 * Copyright © 2009,2010 Red Hat, Inc.
33 * Copyright © 2011,2012 Google, Inc.
34 *
35 * This is part of HarfBuzz, a text shaping library.
36 *
37 * Permission is hereby granted, without written agreement and without
38 * license or royalty fees, to use, copy, modify, and distribute this
39 * software and its documentation for any purpose, provided that the
40 * above copyright notice and the following two paragraphs appear in
41 * all copies of this software.
42 *
43 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
44 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
45 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
46 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
47 * DAMAGE.
48 *
49 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
50 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
51 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
52 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
53 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
54 *
55 * Contributor(s):
56 * Chris Wilson <chris@chris-wilson.co.uk>
57 * Red Hat Author(s): Behdad Esfahbod
58 * Google Author(s): Behdad Esfahbod
59 */
60
61 #ifndef HB_OBJECT_PRIVATE_HH
62 #define HB_OBJECT_PRIVATE_HH
63
64 #include "hb-private.hh"
65
66 #include "hb-atomic-private.hh"
67 #include "hb-mutex-private.hh"
68
69
70 /* Debug */
71
72 #ifndef HB_DEBUG_OBJECT
73 #define HB_DEBUG_OBJECT (HB_DEBUG+0)
74 #endif
75
76
77 /* reference_count */
78
79 #define HB_REFERENCE_COUNT_INERT_VALUE -1
80 #define HB_REFERENCE_COUNT_POISON_VALUE -0x0000DEAD
81 #define HB_REFERENCE_COUNT_INIT {HB_ATOMIC_INT_INIT(HB_REFERENCE_COUNT_INERT_VALUE)}
82
83 struct hb_reference_count_t
84 {
85 hb_atomic_int_t ref_count;
86
87 inline void init (int v) { ref_count.set_unsafe (v); }
88 inline int get_unsafe (void) const { return ref_count.get_unsafe (); }
89 inline int inc (void) { return ref_count.inc (); }
90 inline int dec (void) { return ref_count.dec (); }
91 inline void finish (void) { ref_count.set_unsafe (HB_REFERENCE_COUNT_POISON_VALUE); }
92
93 inline bool is_inert (void) const { return ref_count.get_unsafe () == HB_REFERENCE_COUNT_INERT_VALUE; }
94 inline bool is_valid (void) const { return ref_count.get_unsafe () > 0; }
95 };
96
97
98 /* user_data */
99
100 #define HB_USER_DATA_ARRAY_INIT {HB_MUTEX_INIT, HB_LOCKABLE_SET_INIT}
101 struct hb_user_data_array_t
102 {
103 struct hb_user_data_item_t {
104 hb_user_data_key_t *key;
105 void *data;
106 hb_destroy_func_t destroy;
107
108 inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; }
109 inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; }
110
111 void finish (void) { if (destroy) destroy (data); }
112 };
113
114 hb_mutex_t lock;
115 hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items;
116
117 inline void init (void) { lock.init (); items.init (); }
118
119 HB_INTERNAL bool set (hb_user_data_key_t *key,
120 void * data,
121 hb_destroy_func_t destroy,
122 hb_bool_t replace);
123
124 HB_INTERNAL void *get (hb_user_data_key_t *key);
125
126 inline void finish (void) { items.finish (lock); lock.finish (); }
127 };
128
129
130 /* object_header */
131
132 struct hb_object_header_t
133 {
134 hb_reference_count_t ref_count;
135 hb_user_data_array_t user_data;
136
137 #define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INIT, HB_USER_DATA_ARRAY_INIT}
138
139 private:
140 ASSERT_POD ();
141 };
142
143
144 /* object */
145
146 template <typename Type>
147 static inline void hb_object_trace (const Type *obj, const char *function)
148 {
149 DEBUG_MSG (OBJECT, (void *) obj,
150 "%s refcount=%d",
151 function,
152 obj ? obj->header.ref_count.get_unsafe () : 0);
153 }
154
155 template <typename Type>
156 static inline Type *hb_object_create (void)
157 {
158 Type *obj = (Type *) calloc (1, sizeof (Type));
159
160 if (unlikely (!obj))
161 return obj;
162
163 hb_object_init (obj);
164 hb_object_trace (obj, HB_FUNC);
165 return obj;
166 }
167 template <typename Type>
168 static inline void hb_object_init (Type *obj)
169 {
170 obj->header.ref_count.init (1);
171 obj->header.user_data.init ();
172 }
173 template <typename Type>
174 static inline bool hb_object_is_inert (const Type *obj)
175 {
176 return unlikely (obj->header.ref_count.is_inert ());
177 }
178 template <typename Type>
179 static inline bool hb_object_is_valid (const Type *obj)
180 {
181 return likely (obj->header.ref_count.is_valid ());
182 }
183 template <typename Type>
184 static inline Type *hb_object_reference (Type *obj)
185 {
186 hb_object_trace (obj, HB_FUNC);
187 if (unlikely (!obj || hb_object_is_inert (obj)))
188 return obj;
189 assert (hb_object_is_valid (obj));
190 obj->header.ref_count.inc ();
191 return obj;
192 }
193 template <typename Type>
194 static inline bool hb_object_destroy (Type *obj)
195 {
196 hb_object_trace (obj, HB_FUNC);
197 if (unlikely (!obj || hb_object_is_inert (obj)))
198 return false;
199 assert (hb_object_is_valid (obj));
200 if (obj->header.ref_count.dec () != 1)
201 return false;
202
203 obj->header.ref_count.finish (); /* Do this before user_data */
204 obj->header.user_data.finish ();
205 return true;
206 }
207 template <typename Type>
208 static inline bool hb_object_set_user_data (Type *obj,
209 hb_user_data_key_t *key,
210 void * data,
211 hb_destroy_func_t destroy,
212 hb_bool_t replace)
213 {
214 if (unlikely (!obj || hb_object_is_inert (obj)))
215 return false;
216 assert (hb_object_is_valid (obj));
217 return obj->header.user_data.set (key, data, destroy, replace);
218 }
219
220 template <typename Type>
221 static inline void *hb_object_get_user_data (Type *obj,
222 hb_user_data_key_t *key)
223 {
224 if (unlikely (!obj || hb_object_is_inert (obj)))
225 return NULL;
226 assert (hb_object_is_valid (obj));
227 return obj->header.user_data.get (key);
228 }
229
230
231 #endif /* HB_OBJECT_PRIVATE_HH */