bsnes/nall/string/allocator/vector.hpp

83 lines
1.6 KiB
C++

#pragma once
/*
vector allocator
sizeof(string) == 16 (amd64)
utilizes a raw string pointer
always allocates memory onto the heap when string is not empty
pros:
* potential for in-place resize
* simplicity
cons:
* always allocates heap memory on (capacity > 0)
* pass-by-value requires heap allocation
*/
namespace nall {
auto string::get() -> char* {
if(_capacity == 0) reserve(1);
return _data;
}
auto string::data() const -> const char* {
if(_capacity == 0) return "";
return _data;
}
auto string::reset() -> type& {
if(_data) { memory::free(_data); _data = nullptr; }
_capacity = 0;
_size = 0;
return *this;
}
auto string::reserve(uint capacity) -> type& {
if(capacity > _capacity) {
_capacity = bit::round(capacity + 1) - 1;
_data = (char*)memory::resize(_data, _capacity + 1);
_data[_capacity] = 0;
}
return *this;
}
auto string::resize(uint size) -> type& {
reserve(size);
get()[_size = size] = 0;
return *this;
}
auto string::operator=(const string& source) -> type& {
if(&source == this) return *this;
reset();
_data = (char*)memory::allocate(source._size + 1);
_capacity = source._size;
_size = source._size;
memory::copy(_data, source.data(), source.size() + 1);
return *this;
}
auto string::operator=(string&& source) -> type& {
if(&source == this) return *this;
reset();
_data = source._data;
_capacity = source._capacity;
_size = source._size;
source._data = nullptr;
source._capacity = 0;
source._size = 0;
return *this;
}
string::string() {
_data = nullptr;
_capacity = 0;
_size = 0;
}
}