Function AirportSetBlocks

src/aircraft_cmd.cpp:1903–1939

* "reserve" a block for the plane * @param v airplane that requires the operation * @param current_pos of the vehicle in the list of blocks * @param apc airport on which block is requested to be set * @returns true on success. Eg, next block was free and we have occupied it */

 * @returns true on success. Eg, next block was free and we have occupied it
 */
static bool AirportSetBlocks(Aircraft *v, const AirportFTA *current_pos, const AirportFTAClass *apc)
{
	const AirportFTA *next = &apc->layout[current_pos->next_position];
	const AirportFTA *reference = &apc->layout[v->pos];

	/* if the next position is in another block, check it and wait until it is free */
	if (!apc->layout[current_pos->position].blocks.All(next->blocks)) {
		AirportBlocks blocks = next->blocks;
		/* search for all all elements in the list with the same state, and blocks != N
		 * this means more blocks should be checked/set */
		const AirportFTA *current = current_pos;
		if (current == reference) current = current->next.get();
		while (current != nullptr) {
			if (current->heading == current_pos->heading && current->blocks.Any()) {
				blocks.Set(current->blocks);
				break;
			}
			current = current->next.get();
		}

		/* if the block to be checked is in the next position, then exclude that from
		 * checking, because it has been set by the airplane before */
		if (current_pos->blocks == next->blocks) blocks.Flip(next->blocks);

		Station *st = Station::Get(v->targetairport);
		if (st->airport.blocks.Any(blocks)) {
			v->cur_speed = 0;
			v->subspeed = 0;
			return false;
		}

		if (next->blocks != AirportBlock::Nothing) {
			st->airport.blocks.Set(blocks); // occupy next block
		}
	}
	return true;
}

/**
 * Combination of aircraft state for going to a certain terminal and the