bsnes-libretro/nall/array-span.hpp
Tim Allen 03b06257d3 Update to v106r65 release.
byuu says:

This synchronizes bsnes/higan with many recent internal nall changes.

This will be the last WIP until I am situated in Japan. Apologies for the
bugfixes that didn't get applied yet, I ran out of time.
2018-10-04 20:12:11 +10:00

93 lines
2.6 KiB
C++

#pragma once
#include <nall/array-view.hpp>
namespace nall {
template<typename T> struct array_span : array_view<T> {
using type = array_span;
using super = array_view<T>;
inline array_span() {
super::_data = nullptr;
super::_size = 0;
}
inline array_span(nullptr_t) {
super::_data = nullptr;
super::_size = 0;
}
inline array_span(void* data, uint64_t size) {
super::_data = (T*)data;
super::_size = (int)size;
}
inline operator T*() { return (T*)super::operator const T*(); }
inline auto operator[](uint index) -> T& { return (T&)super::operator[](index); }
template<typename U = T> inline auto data() -> U* { return (U*)super::_data; }
inline auto begin() -> iterator<T> { return {(T*)super::_data, (uint)0}; }
inline auto end() -> iterator<T> { return {(T*)super::_data, (uint)super::_size}; }
inline auto rbegin() -> reverse_iterator<T> { return {(T*)super::_data, (uint)super::_size - 1}; }
inline auto rend() -> reverse_iterator<T> { return {(T*)super::_data, (uint)-1}; }
auto write(T value) -> void {
operator[](0) = value;
super::_data++;
super::_size--;
}
auto span(uint offset, uint length) const -> type {
#ifdef DEBUG
struct out_of_bounds {};
if(offset + length >= super::_size) throw out_of_bounds{};
#endif
return {super::_data + offset, length};
}
//array_span<uint8_t> specializations
template<typename U> auto writel(U value, uint size) -> void;
template<typename U> auto writem(U value, uint size) -> void;
template<typename U> auto writevn(U value, uint size) -> void;
template<typename U> auto writevi(U value, uint size) -> void;
};
//array_span<uint8_t>
template<> inline auto array_span<uint8_t>::write(uint8_t value) -> void {
operator[](0) = value;
_data++;
_size--;
}
template<> template<typename U> inline auto array_span<uint8_t>::writel(U value, uint size) -> void {
for(uint byte : range(size)) write(value >> byte * 8);
}
template<> template<typename U> inline auto array_span<uint8_t>::writem(U value, uint size) -> void {
for(uint byte : reverse(range(size))) write(value >> byte * 8);
}
template<> template<typename U> inline auto array_span<uint8_t>::writevn(U value, uint size) -> void {
while(true) {
auto byte = value & 0x7f;
value >>= 7;
if(value == 0) return write(0x80 | byte);
write(byte);
value--;
}
}
template<> template<typename U> inline auto array_span<uint8_t>::writevi(U value, uint size) -> void {
bool negate = value < 0;
if(negate) value = ~value;
value = value << 1 | negate;
writevn(value);
}
}