/*
* Copyright © 2022 Behdad Esfahbod
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef HB_CPLUSPLUS_HH
#define HB_CPLUSPLUS_HH
#include "hb.h"
#ifdef __cplusplus
#include <functional>
#include <utility>
#if 0
#if !(__cplusplus >= 201103L)
#error "HarfBuzz C++ helpers require C++11"
#endif
#endif
namespace hb {
template <typename T>
struct vtable;
template <typename T>
struct shared_ptr
{
using element_type = T;
using v = vtable<T>;
explicit shared_ptr (T *p = nullptr) : p (p) {}
shared_ptr (const shared_ptr &o) : p (v::reference (o.p)) {}
shared_ptr (shared_ptr &&o) noexcept : p (o.p) { o.p = nullptr; }
shared_ptr& operator = (const shared_ptr &o) { if (p != o.p) { destroy (); p = o.p; reference (); } return *this; }
shared_ptr& operator = (shared_ptr &&o) noexcept { v::destroy (p); p = o.p; o.p = nullptr; return *this; }
~shared_ptr () { v::destroy (p); p = nullptr; }
T* get() const { return p; }
void swap (shared_ptr &o) noexcept { std::swap (p, o.p); }
friend void swap (shared_ptr &a, shared_ptr &b) noexcept { std::swap (a.p, b.p); }
operator T * () const { return p; }
T& operator * () const { return *get (); }
T* operator -> () const { return get (); }
operator bool () const { return p; }
bool operator == (const shared_ptr &o) const { return p == o.p; }
bool operator != (const shared_ptr &o) const { return p != o.p; }
static T* get_empty() { return v::get_empty (); }
T* reference() { return v::reference (p); }
void destroy() { v::destroy (p); }
void set_user_data (hb_user_data_key_t *key,
void *value,
hb_destroy_func_t destroy,
hb_bool_t replace) { v::set_user_data (p, key, value, destroy, replace); }
void * get_user_data (hb_user_data_key_t *key) { return v::get_user_data (p, key); }
private:
T *p;
};
template<typename T> struct is_shared_ptr : std::false_type {};
template<typename T> struct is_shared_ptr<shared_ptr<T>> : std::true_type {};
template <typename T>
struct unique_ptr
{
using element_type = T;
using v = vtable<T>;
explicit unique_ptr (T *p = nullptr) : p (p) {}
unique_ptr (const unique_ptr &o) = delete;
unique_ptr (unique_ptr &&o) noexcept : p (o.p) { o.p = nullptr; }
unique_ptr& operator = (const unique_ptr &o) = delete;
unique_ptr& operator = (unique_ptr &&o) noexcept { v::destroy (p); p = o.p; o.p = nullptr; return *this; }
~unique_ptr () { v::destroy (p); p = nullptr; }
T* get() const { return p; }
T* release () { T* v = p; p = nullptr; return v; }
void swap (unique_ptr &o) noexcept { std::swap (p, o.p); }
friend void swap (unique_ptr &a, unique_ptr &b) noexcept { std::swap (a.p, b.p); }
operator T * () const { return p; }
T& operator * () const { return *get (); }
T* operator -> () const { return get (); }
operator bool () { return p; }
private:
T *p;
};
template<typename T> struct is_unique_ptr : std::false_type {};
template<typename T> struct is_unique_ptr<unique_ptr<T>> : std::true_type {};
template <typename T,
T * (*_get_empty) (void),
T * (*_reference) (T *),
void (*_destroy) (T *),
hb_bool_t (*_set_user_data) (T *,
hb_user_data_key_t *,
void *,
hb_destroy_func_t,
hb_bool_t),
void * (*_get_user_data) (const T *,
hb_user_data_key_t *)>
struct vtable_t
{
static constexpr auto get_empty = _get_empty;
static constexpr auto reference = _reference;
static constexpr auto destroy = _destroy;
static constexpr auto set_user_data = _set_user_data;
static constexpr auto get_user_data = _get_user_data;
};
#define HB_DEFINE_VTABLE(name) \
template<> \
struct vtable<hb_##name##_t> \
: vtable_t<hb_##name##_t, \
&hb_##name##_get_empty, \
&hb_##name##_reference, \
&hb_##name##_destroy, \
&hb_##name##_set_user_data, \
&hb_##name##_get_user_data> {}
HB_DEFINE_VTABLE (buffer);
HB_DEFINE_VTABLE (blob);
HB_DEFINE_VTABLE (face);
HB_DEFINE_VTABLE (font);
HB_DEFINE_VTABLE (font_funcs);
HB_DEFINE_VTABLE (map);
HB_DEFINE_VTABLE (set);
HB_DEFINE_VTABLE (shape_plan);
HB_DEFINE_VTABLE (unicode_funcs);
HB_DEFINE_VTABLE (draw_funcs);
HB_DEFINE_VTABLE (paint_funcs);
#undef HB_DEFINE_VTABLE
#ifdef HB_SUBSET_H
#define HB_DEFINE_VTABLE(name) \
template<> \
struct vtable<hb_##name##_t> \
: vtable_t<hb_##name##_t, \
nullptr, \
&hb_##name##_reference, \
&hb_##name##_destroy, \
&hb_##name##_set_user_data, \
&hb_##name##_get_user_data> {}
HB_DEFINE_VTABLE (subset_input);
HB_DEFINE_VTABLE (subset_plan);
#undef HB_DEFINE_VTABLE
#endif
} // namespace hb
/* Workaround for GCC < 7, see:
* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56480
* https://stackoverflow.com/a/25594741 */
namespace std {
template<typename T>
struct hash<hb::shared_ptr<T>>
{
std::size_t operator()(const hb::shared_ptr<T>& v) const noexcept
{
std::size_t h = std::hash<decltype (v.get ())>{}(v.get ());
return h;
}
};
template<typename T>
struct hash<hb::unique_ptr<T>>
{
std::size_t operator()(const hb::unique_ptr<T>& v) const noexcept
{
std::size_t h = std::hash<decltype (v.get ())>{}(v.get ());
return h;
}
};
} // namespace std
#endif /* __cplusplus */
#endif /* HB_CPLUSPLUS_HH */
