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