OXYGENHUB
◆ main openmsx / src / EmptyPatch.cc
805 B · C++ · last changed chore(): initial commit 1 month ago source blame history raw
1 
#include "EmptyPatch.hh"
2
3 
#include "ranges.hh"
4
5 
#include <algorithm>
6 
#include <cassert>
7
8 
namespace openmsx {
9
10 
void EmptyPatch::copyBlock(size_t src, std::span<uint8_t> dst) const
11 
{
12 
	auto size = block.size();
13 
	if ((src + dst.size()) > size) {
14 
		// past end
15 
		if (size <= src) {
16 
			// start past size, only fill block
17 
			std::ranges::fill(dst, 0);
18 
		} else {
19 
			auto part1 = size - src;
20 
			auto part2 = dst.size() - part1;
21 
			assert(dst.data() != &block[src]);
22 
			copy_to_range(block.subspan(src, part1), dst);
23 
			std::ranges::fill(dst.subspan(part1, part2), 0);
24 
		}
25 
	} else {
26 
		if (dst.data() != &block[src]) {
27 
			// copy_to_range cannot handle overlapping regions, but in
28 
			// that case we don't need to copy at all
29 
			copy_to_range(block.subspan(src, dst.size()), dst);
30 
		}
31 
	}
32 
}
33
34 
} // namespace openmsx