size_t write()

in src/afs.cc [212:273]
61 lines of code
6 McCabe index (conditional complexity)

	size_t write(const void* data, size_t n)
	{
		P("%s: %s: before: (%d:%d) %d", Tag, AFS_FUNC, data_->head, data_->tail, n);
		if (rest_size() == 0)
		{
			P("%s: %s: after: no space: (%d:%d) %d:0",
			  Tag,
			  AFS_FUNC,
			  data_->head,
			  data_->tail,
			  n);
			return 0;
		}

		size_t writtenSize = 0;
		auto output = address();
		if (data_->head <= data_->tail)
		{
			auto restSize = data_->total - data_->tail;
			if (data_->head == 0)
			{
				restSize--;
			}
			const auto firstHalfWriteSize = std::min(n, restSize);
			P("%s: %s: first half: (%d:%d) %d:%d",
			  Tag,
			  AFS_FUNC,
			  data_->head,
			  data_->tail,
			  n,
			  firstHalfWriteSize);
			memcpy(output + data_->tail, data, firstHalfWriteSize);
			data_->tail = (data_->tail + firstHalfWriteSize) % data_->total;
			n -= firstHalfWriteSize;
			writtenSize += firstHalfWriteSize;
		}
		if (n > 0 && rest_size() > 0)
		{
			const auto lastHalfWriteSize = std::min(n, data_->head - data_->tail - 1);
			P("%s: %s: last half: (%d:%d) %d:%d",
			  Tag,
			  AFS_FUNC,
			  data_->head,
			  data_->tail,
			  n,
			  lastHalfWriteSize);
			memcpy(output + data_->tail,
			       static_cast<const uint8_t*>(data) + writtenSize,
			       lastHalfWriteSize);
			data_->tail += lastHalfWriteSize;
			n -= lastHalfWriteSize;
			writtenSize += lastHalfWriteSize;
		}
		P("%s: %s: after: (%d:%d) %d:%d",
		  Tag,
		  AFS_FUNC,
		  data_->head,
		  data_->tail,
		  n,
		  writtenSize);
		return writtenSize;
	}