Check harvester protection for each node it attempts to harvest

[oversword]

Fixes BLS issue 186 BlockySurvival/issue-tracker#186

Performs protection check for each node it attempts to harvest, and exits as soon as it sees a protected node.

Considering there is a protection check outside of the for loop, I have a feeling this wasn't done for efficiency reasons. It would be nice if we could ask if a volume is protected, not just a node, but currently this code is required for security reasons.

One odd feature of this change is that nodes above a protected area will be harvested, but nodes below that protected area will not. I don't think that's such an issue, but we could:

• Loop through the nodes checking for any protection before removing anything, skipping the entire thing if anything is protected
• Skip this iteration of harvesting instead of exiting the function, so that harvest would resume below the protected area

[joe7575]

But you could do the check a few lines later:

	for y_pos = start_y_pos,stop_y_pos,-1 do
		pos.y = y_pos
		local node = minetest.get_node_or_nil(pos)
		if node and node.name ~= "air" then
			local order = tubelib_addons1.FarmingNodes[node.name] or tubelib_addons1.Flowers[node.name]
			if order and not minetest.is_protected(pos, this.owner) then
                                ....

This would be not that time consuming and would allow to harvest nodes below that protected area.

[oversword]

Thanks @joe7575 I'll give that a go in a minute

[oversword]

@joe7575 "would allow to harvest nodes below that protected area" I don't think that's true actually, the else on that condition is

else 	
	return true	-- hit the ground
end

However, I think if I put this on the next line it would skip, like:

	for y_pos = start_y_pos,stop_y_pos,-1 do
		pos.y = y_pos
		local node = minetest.get_node_or_nil(pos)
		if node and node.name ~= "air" then
			local order = tubelib_addons1.FarmingNodes[node.name] or tubelib_addons1.Flowers[node.name]
			if order then
				if not minetest.is_protected(pos, this.owner) and not remove_or_replace_node(this, pos, inv, node, order) then
					return false
				end
			else 	
				return true	-- hit the ground
			end

I'll give it a test, but as long as lua works like other languages the condition should exit before running remove_or_replace_node

[oversword]

@joe7575 That's working now, take another look