third_party/harfbuzz-ng/src/hb-object-private.hh

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