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 (at) 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 #include "hb-debug.hh" 37 38 #include "hb-atomic-private.hh" 39 #include "hb-mutex-private.hh" 40 41 42 /* reference_count */ 43 44 #define HB_REFERENCE_COUNT_INERT_VALUE -1 45 #define HB_REFERENCE_COUNT_POISON_VALUE -0x0000DEAD 46 #define HB_REFERENCE_COUNT_INIT {HB_ATOMIC_INT_INIT(HB_REFERENCE_COUNT_INERT_VALUE)} 47 48 struct hb_reference_count_t 49 { 50 hb_atomic_int_t ref_count; 51 52 inline void init (int v) { ref_count.set_unsafe (v); } 53 inline int get_unsafe (void) const { return ref_count.get_unsafe (); } 54 inline int inc (void) { return ref_count.inc (); } 55 inline int dec (void) { return ref_count.dec (); } 56 inline void finish (void) { ref_count.set_unsafe (HB_REFERENCE_COUNT_POISON_VALUE); } 57 58 inline bool is_inert (void) const { return ref_count.get_unsafe () == HB_REFERENCE_COUNT_INERT_VALUE; } 59 inline bool is_valid (void) const { return ref_count.get_unsafe () > 0; } 60 }; 61 62 63 /* user_data */ 64 65 #define HB_USER_DATA_ARRAY_INIT {HB_MUTEX_INIT, HB_LOCKABLE_SET_INIT} 66 struct hb_user_data_array_t 67 { 68 struct hb_user_data_item_t { 69 hb_user_data_key_t *key; 70 void *data; 71 hb_destroy_func_t destroy; 72 73 inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; } 74 inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; } 75 76 void finish (void) { if (destroy) destroy (data); } 77 }; 78 79 hb_mutex_t lock; 80 hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items; 81 82 inline void init (void) { lock.init (); items.init (); } 83 84 HB_INTERNAL bool set (hb_user_data_key_t *key, 85 void * data, 86 hb_destroy_func_t destroy, 87 hb_bool_t replace); 88 89 HB_INTERNAL void *get (hb_user_data_key_t *key); 90 91 inline void finish (void) { items.finish (lock); lock.finish (); } 92 }; 93 94 95 /* object_header */ 96 97 struct hb_object_header_t 98 { 99 hb_reference_count_t ref_count; 100 hb_user_data_array_t user_data; 101 102 #define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INIT, HB_USER_DATA_ARRAY_INIT} 103 104 private: 105 ASSERT_POD (); 106 }; 107 108 109 /* object */ 110 111 template <typename Type> 112 static inline void hb_object_trace (const Type *obj, const char *function) 113 { 114 DEBUG_MSG (OBJECT, (void *) obj, 115 "%s refcount=%d", 116 function, 117 obj ? obj->header.ref_count.get_unsafe () : 0); 118 } 119 120 template <typename Type> 121 static inline Type *hb_object_create (void) 122 { 123 Type *obj = (Type *) calloc (1, sizeof (Type)); 124 125 if (unlikely (!obj)) 126 return obj; 127 128 hb_object_init (obj); 129 hb_object_trace (obj, HB_FUNC); 130 return obj; 131 } 132 template <typename Type> 133 static inline void hb_object_init (Type *obj) 134 { 135 obj->header.ref_count.init (1); 136 obj->header.user_data.init (); 137 } 138 template <typename Type> 139 static inline bool hb_object_is_inert (const Type *obj) 140 { 141 return unlikely (obj->header.ref_count.is_inert ()); 142 } 143 template <typename Type> 144 static inline bool hb_object_is_valid (const Type *obj) 145 { 146 return likely (obj->header.ref_count.is_valid ()); 147 } 148 template <typename Type> 149 static inline Type *hb_object_reference (Type *obj) 150 { 151 hb_object_trace (obj, HB_FUNC); 152 if (unlikely (!obj || hb_object_is_inert (obj))) 153 return obj; 154 assert (hb_object_is_valid (obj)); 155 obj->header.ref_count.inc (); 156 return obj; 157 } 158 template <typename Type> 159 static inline bool hb_object_destroy (Type *obj) 160 { 161 hb_object_trace (obj, HB_FUNC); 162 if (unlikely (!obj || hb_object_is_inert (obj))) 163 return false; 164 assert (hb_object_is_valid (obj)); 165 if (obj->header.ref_count.dec () != 1) 166 return false; 167 168 obj->header.ref_count.finish (); /* Do this before user_data */ 169 obj->header.user_data.finish (); 170 return true; 171 } 172 template <typename Type> 173 static inline bool hb_object_set_user_data (Type *obj, 174 hb_user_data_key_t *key, 175 void * data, 176 hb_destroy_func_t destroy, 177 hb_bool_t replace) 178 { 179 if (unlikely (!obj || hb_object_is_inert (obj))) 180 return false; 181 assert (hb_object_is_valid (obj)); 182 return obj->header.user_data.set (key, data, destroy, replace); 183 } 184 185 template <typename Type> 186 static inline void *hb_object_get_user_data (Type *obj, 187 hb_user_data_key_t *key) 188 { 189 if (unlikely (!obj || hb_object_is_inert (obj))) 190 return nullptr; 191 assert (hb_object_is_valid (obj)); 192 return obj->header.user_data.get (key); 193 } 194 195 196 #endif /* HB_OBJECT_PRIVATE_HH */ 197