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   /* TODO Add tracing. */
  72
  73   struct hb_user_data_item_t {
  74     hb_user_data_key_t *key;
  75     void *data;
  76     hb_destroy_func_t destroy;
  77
  78     inline bool operator == (hb_user_data_key_t *other_key) const { return key == other_key; }
  79     inline bool operator == (hb_user_data_item_t &other) const { return key == other.key; }
  80
  81     void finish (void) { if (destroy) destroy (data); }
  82   };
  83
  84   hb_mutex_t lock;
  85   hb_lockable_set_t<hb_user_data_item_t, hb_mutex_t> items;
  86
  87   inline void init (void) { lock.init (); items.init (); }
  88
  89   HB_INTERNAL bool set (hb_user_data_key_t *key,
  90                         void *              data,
  91                         hb_destroy_func_t   destroy,
  92                         hb_bool_t           replace);
  93
  94   HB_INTERNAL void *get (hb_user_data_key_t *key);
  95
  96   inline void finish (void) { items.finish (lock); lock.finish (); }
  97 };
  98
  99
 100 /* object_header */
 101
 102 struct hb_object_header_t
 103 {
 104   hb_reference_count_t ref_count;
 105   hb_user_data_array_t user_data;
 106
 107 #define HB_OBJECT_HEADER_STATIC {HB_REFERENCE_COUNT_INVALID, HB_USER_DATA_ARRAY_INIT}
 108
 109   static inline void *create (unsigned int size) {
 110     hb_object_header_t *obj = (hb_object_header_t *) calloc (1, size);
 111
 112     if (likely (obj))
 113       obj->init ();
 114
 115     return obj;
 116   }
 117
 118   inline void init (void) {
 119     ref_count.init (1);
 120     user_data.init ();
 121   }
 122
 123   inline bool is_inert (void) const {
 124     return unlikely (ref_count.is_invalid ());
 125   }
 126
 127   inline void reference (void) {
 128     if (unlikely (!this || this->is_inert ()))
 129       return;
 130     ref_count.inc ();
 131   }
 132
 133   inline bool destroy (void) {
 134     if (unlikely (!this || this->is_inert ()))
 135       return false;
 136     if (ref_count.dec () != 1)
 137       return false;
 138
 139     ref_count.finish (); /* Do this before user_data */
 140     user_data.finish ();
 141
 142     return true;
 143   }
 144
 145   inline bool set_user_data (hb_user_data_key_t *key,
 146                              void *              data,
 147                              hb_destroy_func_t   destroy_func,
 148                              hb_bool_t           replace) {
 149     if (unlikely (!this || this->is_inert ()))
 150       return false;
 151
 152     return user_data.set (key, data, destroy_func, replace);
 153   }
 154
 155   inline void *get_user_data (hb_user_data_key_t *key) {
 156     if (unlikely (!this || this->is_inert ()))
 157       return NULL;
 158
 159     return user_data.get (key);
 160   }
 161
 162   inline void trace (const char *function) const {
 163     if (unlikely (!this)) return;
 164     /* TODO We cannot use DEBUG_MSG_FUNC here since that one currently only
 165      * prints the class name and throws away the template info. */
 166     DEBUG_MSG (OBJECT, (void *) this,
 167                "%s refcount=%d",
 168                function,
 169                this ? ref_count.ref_count : 0);
 170   }
 171
 172   private:
 173   ASSERT_POD ();
 174 };
 175
 176
 177 /* object */
 178
 179 template <typename Type>
 180 static inline void hb_object_trace (const Type *obj, const char *function)
 181 {
 182   obj->header.trace (function);
 183 }
 184 template <typename Type>
 185 static inline Type *hb_object_create (void)
 186 {
 187   Type *obj = (Type *) hb_object_header_t::create (sizeof (Type));
 188   hb_object_trace (obj, HB_FUNC);
 189   return obj;
 190 }
 191 template <typename Type>
 192 static inline bool hb_object_is_inert (const Type *obj)
 193 {
 194   return unlikely (obj->header.is_inert ());
 195 }
 196 template <typename Type>
 197 static inline Type *hb_object_reference (Type *obj)
 198 {
 199   hb_object_trace (obj, HB_FUNC);
 200   obj->header.reference ();
 201   return obj;
 202 }
 203 template <typename Type>
 204 static inline bool hb_object_destroy (Type *obj)
 205 {
 206   hb_object_trace (obj, HB_FUNC);
 207   return obj->header.destroy ();
 208 }
 209 template <typename Type>
 210 static inline bool hb_object_set_user_data (Type               *obj,
 211                                             hb_user_data_key_t *key,
 212                                             void *              data,
 213                                             hb_destroy_func_t   destroy,
 214                                             hb_bool_t           replace)
 215 {
 216   return obj->header.set_user_data (key, data, destroy, replace);
 217 }
 218
 219 template <typename Type>
 220 static inline void *hb_object_get_user_data (Type               *obj,
 221                                              hb_user_data_key_t *key)
 222 {
 223   return obj->header.get_user_data (key);
 224 }
 225
 226
 227 #endif /* HB_OBJECT_PRIVATE_HH */