size_t read()

in src/afs.cc [275:320]

• 46 lines of code
• 4 McCabe index (conditional complexity)

	size_t read(size_t n, void* output)
	{
		P("%s: %s: before: (%d:%d) %d", Tag, AFS_FUNC, data_->head, data_->tail, n);
		size_t readSize = 0;
		const auto input = address();
		if (data_->head > data_->tail)
		{
			const auto firstHalfReadSize = std::min(n, data_->total - data_->head);
			P("%s: %s: first half: (%d:%d) %d:%d",
			  Tag,
			  AFS_FUNC,
			  data_->head,
			  data_->tail,
			  n,
			  firstHalfReadSize);
			memcpy(output, input + data_->head, firstHalfReadSize);
			data_->head = (data_->head + firstHalfReadSize) % data_->total;
			n -= firstHalfReadSize;
			readSize += firstHalfReadSize;
		}
		if (n > 0 && data_->head != data_->tail)
		{
			const auto lastHalfReadSize = std::min(n, data_->tail - data_->head);
			P("%s: %s: last half: (%d:%d) %d:%d",
			  Tag,
			  AFS_FUNC,
			  data_->head,
			  data_->tail,
			  n,
			  lastHalfReadSize);
			memcpy(static_cast<uint8_t*>(output) + readSize,
			       input + data_->head,
			       lastHalfReadSize);
			data_->head += lastHalfReadSize;
			n -= lastHalfReadSize;
			readSize += lastHalfReadSize;
		}
		P("%s: %s: after: (%d:%d) %d:%d",
		  Tag,
		  AFS_FUNC,
		  data_->head,
		  data_->tail,
		  n,
		  readSize);
		return readSize;
	}