1 /* 2 * Copyright © 2022 Behdad Esfahbod 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 */ 24 25 #ifndef HB_CPLUSPLUS_HH 26 #define HB_CPLUSPLUS_HH 27 28 #include "hb.h" 29 30 HB_BEGIN_DECLS 31 HB_END_DECLS 32 33 #ifdef __cplusplus 34 35 #include <functional> 36 #include <utility> 37 38 #if 0 39 #if !(__cplusplus >= 201103L) 40 #error "HarfBuzz C++ helpers require C++11" 41 #endif 42 #endif 43 44 namespace hb { 45 46 47 template <typename T> 48 struct vtable; 49 50 template <typename T> 51 struct shared_ptr 52 { 53 using element_type = T; 54 55 using v = vtable<T>; 56 shared_ptrhb::shared_ptr57 explicit shared_ptr (T *p = nullptr) : p (p) {} shared_ptrhb::shared_ptr58 shared_ptr (const shared_ptr &o) : p (v::reference (o.p)) {} shared_ptrhb::shared_ptr59 shared_ptr (shared_ptr &&o) : p (o.p) { o.p = nullptr; } operator =hb::shared_ptr60 shared_ptr& operator = (const shared_ptr &o) { if (p != o.p) { destroy (); p = o.p; reference (); } return *this; } operator =hb::shared_ptr61 shared_ptr& operator = (shared_ptr &&o) { v::destroy (p); p = o.p; o.p = nullptr; return *this; } ~shared_ptrhb::shared_ptr62 ~shared_ptr () { v::destroy (p); p = nullptr; } 63 gethb::shared_ptr64 T* get() const { return p; } 65 swaphb::shared_ptr66 void swap (shared_ptr &o) { std::swap (p, o.p); } swap(shared_ptr & a,shared_ptr & b)67 friend void swap (shared_ptr &a, shared_ptr &b) { std::swap (a.p, b.p); } 68 operator T*hb::shared_ptr69 operator T * () const { return p; } operator *hb::shared_ptr70 T& operator * () const { return *get (); } operator ->hb::shared_ptr71 T* operator -> () const { return get (); } operator boolhb::shared_ptr72 operator bool () const { return p; } operator ==hb::shared_ptr73 bool operator == (const shared_ptr &o) const { return p == o.p; } operator !=hb::shared_ptr74 bool operator != (const shared_ptr &o) const { return p != o.p; } 75 get_emptyhb::shared_ptr76 static T* get_empty() { return v::get_empty (); } referencehb::shared_ptr77 T* reference() { return v::reference (p); } destroyhb::shared_ptr78 void destroy() { v::destroy (p); } set_user_datahb::shared_ptr79 void set_user_data (hb_user_data_key_t *key, 80 void *value, 81 hb_destroy_func_t destroy, 82 hb_bool_t replace) { v::set_user_data (p, key, value, destroy, replace); } get_user_datahb::shared_ptr83 void * get_user_data (hb_user_data_key_t *key) { return v::get_user_data (p, key); } 84 85 private: 86 T *p; 87 }; 88 89 template<typename T> struct is_shared_ptr : std::false_type {}; 90 template<typename T> struct is_shared_ptr<shared_ptr<T>> : std::true_type {}; 91 92 template <typename T> 93 struct unique_ptr 94 { 95 using element_type = T; 96 97 using v = vtable<T>; 98 unique_ptrhb::unique_ptr99 explicit unique_ptr (T *p = nullptr) : p (p) {} 100 unique_ptr (const unique_ptr &o) = delete; unique_ptrhb::unique_ptr101 unique_ptr (unique_ptr &&o) : p (o.p) { o.p = nullptr; } 102 unique_ptr& operator = (const unique_ptr &o) = delete; operator =hb::unique_ptr103 unique_ptr& operator = (unique_ptr &&o) { v::destroy (p); p = o.p; o.p = nullptr; return *this; } ~unique_ptrhb::unique_ptr104 ~unique_ptr () { v::destroy (p); p = nullptr; } 105 gethb::unique_ptr106 T* get() const { return p; } releasehb::unique_ptr107 T* release () { T* v = p; p = nullptr; return v; } 108 swaphb::unique_ptr109 void swap (unique_ptr &o) { std::swap (p, o.p); } swap(unique_ptr & a,unique_ptr & b)110 friend void swap (unique_ptr &a, unique_ptr &b) { std::swap (a.p, b.p); } 111 operator T*hb::unique_ptr112 operator T * () const { return p; } operator *hb::unique_ptr113 T& operator * () const { return *get (); } operator ->hb::unique_ptr114 T* operator -> () const { return get (); } operator boolhb::unique_ptr115 operator bool () { return p; } 116 117 private: 118 T *p; 119 }; 120 121 template<typename T> struct is_unique_ptr : std::false_type {}; 122 template<typename T> struct is_unique_ptr<unique_ptr<T>> : std::true_type {}; 123 124 template <typename T, 125 T * (*_get_empty) (void), 126 T * (*_reference) (T *), 127 void (*_destroy) (T *), 128 hb_bool_t (*_set_user_data) (T *, 129 hb_user_data_key_t *, 130 void *, 131 hb_destroy_func_t, 132 hb_bool_t), 133 void * (*_get_user_data) (const T *, 134 hb_user_data_key_t *)> 135 struct vtable_t 136 { 137 static constexpr auto get_empty = _get_empty; 138 static constexpr auto reference = _reference; 139 static constexpr auto destroy = _destroy; 140 static constexpr auto set_user_data = _set_user_data; 141 static constexpr auto get_user_data = _get_user_data; 142 }; 143 144 #define HB_DEFINE_VTABLE(name) \ 145 template<> \ 146 struct vtable<hb_##name##_t> \ 147 : vtable_t<hb_##name##_t, \ 148 &hb_##name##_get_empty, \ 149 &hb_##name##_reference, \ 150 &hb_##name##_destroy, \ 151 &hb_##name##_set_user_data, \ 152 &hb_##name##_get_user_data> {} 153 154 HB_DEFINE_VTABLE (buffer); 155 HB_DEFINE_VTABLE (blob); 156 HB_DEFINE_VTABLE (face); 157 HB_DEFINE_VTABLE (font); 158 HB_DEFINE_VTABLE (font_funcs); 159 HB_DEFINE_VTABLE (map); 160 HB_DEFINE_VTABLE (set); 161 HB_DEFINE_VTABLE (shape_plan); 162 HB_DEFINE_VTABLE (unicode_funcs); 163 164 #undef HB_DEFINE_VTABLE 165 166 167 #ifdef HB_SUBSET_H 168 169 #define HB_DEFINE_VTABLE(name) \ 170 template<> \ 171 struct vtable<hb_##name##_t> \ 172 : vtable_t<hb_##name##_t, \ 173 nullptr, \ 174 &hb_##name##_reference, \ 175 &hb_##name##_destroy, \ 176 &hb_##name##_set_user_data, \ 177 &hb_##name##_get_user_data> {} 178 179 180 HB_DEFINE_VTABLE (subset_input); 181 HB_DEFINE_VTABLE (subset_plan); 182 183 #undef HB_DEFINE_VTABLE 184 185 #endif 186 187 188 } // namespace hb 189 190 /* Workaround for GCC < 7, see: 191 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56480 192 * https://stackoverflow.com/a/25594741 */ 193 namespace std { 194 195 196 template<typename T> 197 struct hash<hb::shared_ptr<T>> 198 { operator ()std::hash199 std::size_t operator()(const hb::shared_ptr<T>& v) const noexcept 200 { 201 std::size_t h = std::hash<decltype (v.get ())>{}(v.get ()); 202 return h; 203 } 204 }; 205 206 template<typename T> 207 struct hash<hb::unique_ptr<T>> 208 { operator ()std::hash209 std::size_t operator()(const hb::unique_ptr<T>& v) const noexcept 210 { 211 std::size_t h = std::hash<decltype (v.get ())>{}(v.get ()); 212 return h; 213 } 214 }; 215 216 217 } // namespace std 218 219 #endif /* __cplusplus */ 220 221 #endif /* HB_CPLUSPLUS_HH */ 222