mesecons/mesecons/internal.lua
Jeija e5896076fe Make sure #160 cannot be exploited to make servers crash.
This is not exactly a fix for the issue, because extremely
large circuits (3000+ conductors) still won't work with this applied.
This simply aborts any execution if there is the danger of a stack overflow.
2014-06-01 11:00:39 +02:00

709 lines
22 KiB
Lua

-- Internal.lua - The core of mesecons
--
-- For more practical developer resources see mesecons.tk
--
-- Function overview
-- mesecon:get_effector(nodename) --> Returns the mesecons.effector -specifictation in the nodedef by the nodename
-- mesecon:get_receptor(nodename) --> Returns the mesecons.receptor -specifictation in the nodedef by the nodename
-- mesecon:get_conductor(nodename) --> Returns the mesecons.conductor-specifictation in the nodedef by the nodename
-- mesecon:get_any_inputrules (node) --> Returns the rules of a node if it is a conductor or an effector
-- mesecon:get_any_outputrules (node) --> Returns the rules of a node if it is a conductor or a receptor
-- RECEPTORS
-- mesecon:is_receptor(nodename) --> Returns true if nodename is a receptor
-- mesecon:is_receptor_on(nodename) --> Returns true if nodename is an receptor with state = mesecon.state.on
-- mesecon:is_receptor_off(nodename) --> Returns true if nodename is an receptor with state = mesecon.state.off
-- mesecon:receptor_get_rules(node) --> Returns the rules of the receptor (mesecon.rules.default if none specified)
-- EFFECTORS
-- mesecon:is_effector(nodename) --> Returns true if nodename is an effector
-- mesecon:is_effector_on(nodename) --> Returns true if nodename is an effector with nodedef.mesecons.effector.action_off
-- mesecon:is_effector_off(nodename) --> Returns true if nodename is an effector with nodedef.mesecons.effector.action_on
-- mesecon:effector_get_rules(node) --> Returns the input rules of the effector (mesecon.rules.default if none specified)
-- SIGNALS
-- mesecon:activate(pos, node, recdepth) --> Activates the effector node at the specific pos (calls nodedef.mesecons.effector.action_on), higher recdepths are executed later
-- mesecon:deactivate(pos, node, recdepth) --> Deactivates the effector node at the specific pos (calls nodedef.mesecons.effector.action_off), "
-- mesecon:changesignal(pos, node, rulename, newstate) --> Changes the effector node at the specific pos (calls nodedef.mesecons.effector.action_change), "
-- RULES
-- mesecon:add_rules(name, rules) | deprecated? --> Saves rules table by name
-- mesecon:get_rules(name, rules) | deprecated? --> Loads rules table with name
-- CONDUCTORS
-- mesecon:is_conductor(nodename) --> Returns true if nodename is a conductor
-- mesecon:is_conductor_on(node) --> Returns true if node is a conductor with state = mesecon.state.on
-- mesecon:is_conductor_off(node) --> Returns true if node is a conductor with state = mesecon.state.off
-- mesecon:get_conductor_on(node_off) --> Returns the onstate nodename of the conductor
-- mesecon:get_conductor_off(node_on) --> Returns the offstate nodename of the conductor
-- mesecon:conductor_get_rules(node) --> Returns the input+output rules of a conductor (mesecon.rules.default if none specified)
-- HIGH-LEVEL Internals
-- mesecon:is_power_on(pos) --> Returns true if pos emits power in any way
-- mesecon:is_power_off(pos) --> Returns true if pos does not emit power in any way
-- mesecon:turnon(pos, rulename) --> Returns true whatever there is at pos. Calls itself for connected nodes (if pos is a conductor) --> recursive, the rulename is the name of the input rule that caused calling turnon; Uses third parameter recdepth internally to determine how far away the current node is from the initial pos as it uses recursion
-- mesecon:turnoff(pos, rulename) --> Turns off whatever there is at pos. Calls itself for connected nodes (if pos is a conductor) --> recursive, the rulename is the name of the input rule that caused calling turnoff; Uses third parameter recdepth internally to determine how far away the current node is from the initial pos as it uses recursion
-- mesecon:connected_to_receptor(pos) --> Returns true if pos is connected to a receptor directly or via conductors; calls itself if pos is a conductor --> recursive
-- mesecon:rules_link(output, input, dug_outputrules) --> Returns true if outputposition + outputrules = inputposition and inputposition + inputrules = outputposition (if the two positions connect)
-- mesecon:rules_link_anydir(outp., inp., d_outpr.) --> Same as rules mesecon:rules_link but also returns true if output and input are swapped
-- mesecon:is_powered(pos) --> Returns true if pos is powered by a receptor or a conductor
-- RULES ROTATION helpsers
-- mesecon:rotate_rules_right(rules)
-- mesecon:rotate_rules_left(rules)
-- mesecon:rotate_rules_up(rules)
-- mesecon:rotate_rules_down(rules)
-- These functions return rules that have been rotated in the specific direction
-- General
function mesecon:get_effector(nodename)
if minetest.registered_nodes[nodename]
and minetest.registered_nodes[nodename].mesecons
and minetest.registered_nodes[nodename].mesecons.effector then
return minetest.registered_nodes[nodename].mesecons.effector
end
end
function mesecon:get_receptor(nodename)
if minetest.registered_nodes[nodename]
and minetest.registered_nodes[nodename].mesecons
and minetest.registered_nodes[nodename].mesecons.receptor then
return minetest.registered_nodes[nodename].mesecons.receptor
end
end
function mesecon:get_conductor(nodename)
if minetest.registered_nodes[nodename]
and minetest.registered_nodes[nodename].mesecons
and minetest.registered_nodes[nodename].mesecons.conductor then
return minetest.registered_nodes[nodename].mesecons.conductor
end
end
function mesecon:get_any_outputrules (node)
if mesecon:is_conductor(node.name) then
return mesecon:conductor_get_rules(node)
elseif mesecon:is_receptor(node.name) then
return mesecon:receptor_get_rules(node)
end
return false
end
function mesecon:get_any_inputrules (node)
if mesecon:is_conductor(node.name) then
return mesecon:conductor_get_rules(node)
elseif mesecon:is_effector(node.name) then
return mesecon:effector_get_rules(node)
end
return false
end
-- Receptors
-- Nodes that can power mesecons
function mesecon:is_receptor_on(nodename)
local receptor = mesecon:get_receptor(nodename)
if receptor and receptor.state == mesecon.state.on then
return true
end
return false
end
function mesecon:is_receptor_off(nodename)
local receptor = mesecon:get_receptor(nodename)
if receptor and receptor.state == mesecon.state.off then
return true
end
return false
end
function mesecon:is_receptor(nodename)
local receptor = mesecon:get_receptor(nodename)
if receptor then
return true
end
return false
end
function mesecon:receptor_get_rules(node)
local receptor = mesecon:get_receptor(node.name)
if receptor then
local rules = receptor.rules
if type(rules) == 'function' then
return rules(node)
elseif rules then
return rules
end
end
return mesecon.rules.default
end
-- Effectors
-- Nodes that can be powered by mesecons
function mesecon:is_effector_on(nodename)
local effector = mesecon:get_effector(nodename)
if effector and effector.action_off then
return true
end
return false
end
function mesecon:is_effector_off(nodename)
local effector = mesecon:get_effector(nodename)
if effector and effector.action_on then
return true
end
return false
end
function mesecon:is_effector(nodename)
local effector = mesecon:get_effector(nodename)
if effector then
return true
end
return false
end
function mesecon:effector_get_rules(node)
local effector = mesecon:get_effector(node.name)
if effector then
local rules = effector.rules
if type(rules) == 'function' then
return rules(node)
elseif rules then
return rules
end
end
return mesecon.rules.default
end
-- #######################
-- # Signals (effectors) #
-- #######################
-- Activation:
mesecon.queue:add_function("activate", function (pos, rulename)
node = minetest.get_node(pos)
effector = mesecon:get_effector(node.name)
if effector and effector.action_on then
effector.action_on(pos, node, rulename)
end
end)
function mesecon:activate(pos, node, rulename, recdepth)
if rulename == nil then
for _,rule in ipairs(mesecon:effector_get_rules(node)) do
mesecon:activate(pos, node, rule, recdepth + 1)
end
return
end
mesecon.queue:add_action(pos, "activate", {rulename}, nil, rulename, 1 / recdepth)
end
-- Deactivation
mesecon.queue:add_function("deactivate", function (pos, rulename)
node = minetest.get_node(pos)
effector = mesecon:get_effector(node.name)
if effector and effector.action_off then
effector.action_off(pos, node, rulename)
end
end)
function mesecon:deactivate(pos, node, rulename, recdepth)
if rulename == nil then
for _,rule in ipairs(mesecon:effector_get_rules(node)) do
mesecon:deactivate(pos, node, rule, recdepth + 1)
end
return
end
mesecon.queue:add_action(pos, "deactivate", {rulename}, nil, rulename, 1 / recdepth)
end
-- Change
mesecon.queue:add_function("change", function (pos, rulename, changetype)
node = minetest.get_node(pos)
effector = mesecon:get_effector(node.name)
if effector and effector.action_change then
effector.action_change(pos, node, rulename, changetype)
end
end)
function mesecon:changesignal(pos, node, rulename, newstate, recdepth)
if rulename == nil then
for _,rule in ipairs(mesecon:effector_get_rules(node)) do
mesecon:changesignal(pos, node, rule, newstate, recdepth + 1)
end
return
end
mesecon.queue:add_action(pos, "change", {rulename, newstate}, nil, rulename, 1 / recdepth)
end
-- #########
-- # Rules # "Database" for rulenames
-- #########
function mesecon:add_rules(name, rules)
mesecon.rules[name] = rules
end
function mesecon:get_rules(name)
return mesecon.rules[name]
end
-- Conductors
function mesecon:is_conductor_on(node, rulename)
local conductor = mesecon:get_conductor(node.name)
if conductor then
if conductor.state then
return conductor.state == mesecon.state.on
end
if conductor.states then
if not rulename then
return mesecon:getstate(node.name, conductor.states) ~= 1
end
local bit = mesecon:rule2bit(rulename, mesecon:conductor_get_rules(node))
local binstate = mesecon:getbinstate(node.name, conductor.states)
return mesecon:get_bit(binstate, bit)
end
end
return false
end
function mesecon:is_conductor_off(node, rulename)
local conductor = mesecon:get_conductor(node.name)
if conductor then
if conductor.state then
return conductor.state == mesecon.state.off
end
if conductor.states then
if not rulename then
return mesecon:getstate(node.name, conductor.states) == 1
end
local bit = mesecon:rule2bit(rulename, mesecon:conductor_get_rules(node))
local binstate = mesecon:getbinstate(node.name, conductor.states)
return not mesecon:get_bit(binstate, bit)
end
end
return false
end
function mesecon:is_conductor(nodename)
local conductor = mesecon:get_conductor(nodename)
if conductor then
return true
end
return false
end
function mesecon:get_conductor_on(node_off, rulename)
local conductor = mesecon:get_conductor(node_off.name)
if conductor then
if conductor.onstate then
return conductor.onstate
end
if conductor.states then
local bit = mesecon:rule2bit(rulename, mesecon:conductor_get_rules(node_off))
local binstate = mesecon:getbinstate(node_off.name, conductor.states)
binstate = mesecon:set_bit(binstate, bit, "1")
return conductor.states[tonumber(binstate,2)+1]
end
end
return offstate
end
function mesecon:get_conductor_off(node_on, rulename)
local conductor = mesecon:get_conductor(node_on.name)
if conductor then
if conductor.offstate then
return conductor.offstate
end
if conductor.states then
local bit = mesecon:rule2bit(rulename, mesecon:conductor_get_rules(node_on))
local binstate = mesecon:getbinstate(node_on.name, conductor.states)
binstate = mesecon:set_bit(binstate, bit, "0")
return conductor.states[tonumber(binstate,2)+1]
end
end
return onstate
end
function mesecon:conductor_get_rules(node)
local conductor = mesecon:get_conductor(node.name)
if conductor then
local rules = conductor.rules
if type(rules) == 'function' then
return rules(node)
elseif rules then
return rules
end
end
return mesecon.rules.default
end
-- some more general high-level stuff
function mesecon:is_power_on(pos, rulename)
local node = minetest.get_node(pos)
if mesecon:is_conductor_on(node, rulename) or mesecon:is_receptor_on(node.name) then
return true
end
return false
end
function mesecon:is_power_off(pos, rulename)
local node = minetest.get_node(pos)
if mesecon:is_conductor_off(node, rulename) or mesecon:is_receptor_off(node.name) then
return true
end
return false
end
function mesecon:turnon(pos, rulename, recdepth)
recdepth = recdepth or 2
if (recdepth > STACK_SIZE) then return end
local node = minetest.get_node(pos)
if(node.name == "ignore") then
-- try turning on later again
mesecon.queue:add_action(
pos, "turnon", {rulename, recdepth + 1}, nil, true)
end
if mesecon:is_conductor_off(node, rulename) then
local rules = mesecon:conductor_get_rules(node)
if not rulename then
for _, rule in ipairs(mesecon:flattenrules(rules)) do
if mesecon:connected_to_receptor(pos, rule) then
mesecon:turnon(pos, rule, recdepth + 1)
end
end
return
end
minetest.swap_node(pos, {name = mesecon:get_conductor_on(node, rulename), param2 = node.param2})
for _, rule in ipairs(mesecon:rule2meta(rulename, rules)) do
local np = mesecon:addPosRule(pos, rule)
if(minetest.get_node(np).name == "ignore") then
-- try turning on later again
mesecon.queue:add_action(
np, "turnon", {rulename, recdepth + 1}, nil, true)
else
local rulenames = mesecon:rules_link_rule_all(pos, rule)
for _, rulename in ipairs(rulenames) do
mesecon:turnon(np, rulename, recdepth + 1)
end
end
end
elseif mesecon:is_effector(node.name) then
mesecon:changesignal(pos, node, rulename, mesecon.state.on, recdepth)
if mesecon:is_effector_off(node.name) then
mesecon:activate(pos, node, rulename, recdepth)
end
end
end
mesecon.queue:add_function("turnon", function (pos, rulename, recdepth)
mesecon:turnon(pos, rulename, recdepth)
end)
function mesecon:turnoff(pos, rulename, recdepth)
recdepth = recdepth or 2
if (recdepth > STACK_SIZE) then return end
local node = minetest.get_node(pos)
if(node.name == "ignore") then
-- try turning on later again
mesecon.queue:add_action(
pos, "turnoff", {rulename, recdepth + 1}, nil, true)
end
if mesecon:is_conductor_on(node, rulename) then
local rules = mesecon:conductor_get_rules(node)
minetest.swap_node(pos, {name = mesecon:get_conductor_off(node, rulename), param2 = node.param2})
for _, rule in ipairs(mesecon:rule2meta(rulename, rules)) do
local np = mesecon:addPosRule(pos, rule)
if(minetest.get_node(np).name == "ignore") then
-- try turning on later again
mesecon.queue:add_action(
np, "turnoff", {rulename, recdepth + 1}, nil, true)
else
local rulenames = mesecon:rules_link_rule_all(pos, rule)
for _, rulename in ipairs(rulenames) do
mesecon:turnoff(np, rulename, recdepth + 1)
end
end
end
elseif mesecon:is_effector(node.name) then
mesecon:changesignal(pos, node, rulename, mesecon.state.off, recdepth)
if mesecon:is_effector_on(node.name)
and not mesecon:is_powered(pos) then
mesecon:deactivate(pos, node, rulename, recdepth + 1)
end
end
end
mesecon.queue:add_function("turnoff", function (pos, rulename, recdepth)
mesecon:turnoff(pos, rulename, recdepth)
end)
function mesecon:connected_to_receptor(pos, rulename)
local node = minetest.get_node(pos)
-- Check if conductors around are connected
local rules = mesecon:get_any_inputrules(node)
if not rules then return false end
for _, rule in ipairs(mesecon:rule2meta(rulename, rules)) do
local rulenames = mesecon:rules_link_rule_all_inverted(pos, rule)
for _, rname in ipairs(rulenames) do
local np = mesecon:addPosRule(pos, rname)
if mesecon:find_receptor_on(np, {}, mesecon:invertRule(rname)) then
return true
end
end
end
return false
end
function mesecon:find_receptor_on(pos, checked, rulename, recdepth)
recdepth = recdepth or 2
if (recdepth > STACK_SIZE) then return true end -- ignore request
local node = minetest.get_node(pos)
if mesecon:is_receptor_on(node.name) then
-- add current position to checked
table.insert(checked, {x=pos.x, y=pos.y, z=pos.z})
return true
end
if mesecon:is_conductor(node.name) then
local rules = mesecon:conductor_get_rules(node)
local metaindex = mesecon:rule2metaindex(rulename, rules)
-- find out if node has already been checked (to prevent from endless loop)
for _, cp in ipairs(checked) do
if mesecon:cmpPos(cp, pos) and cp.metaindex == metaindex then
return false, checked
end
end
-- add current position to checked
table.insert(checked, {x=pos.x, y=pos.y, z=pos.z, metaindex = metaindex})
for _, rule in ipairs(mesecon:rule2meta(rulename, rules)) do
local rulenames = mesecon:rules_link_rule_all_inverted(pos, rule)
for _, rname in ipairs(rulenames) do
local np = mesecon:addPosRule(pos, rname)
if mesecon:find_receptor_on(np, checked, mesecon:invertRule(rname), recdepth + 1) then
return true
end
end
end
else
-- find out if node has already been checked (to prevent from endless loop)
for _, cp in ipairs(checked) do
if mesecon:cmpPos(cp, pos) then
return false, checked
end
end
table.insert(checked, {x=pos.x, y=pos.y, z=pos.z})
end
return false
end
function mesecon:rules_link(output, input, dug_outputrules) --output/input are positions (outputrules optional, used if node has been dug), second return value: the name of the affected input rule
local outputnode = minetest.get_node(output)
local inputnode = minetest.get_node(input)
local outputrules = dug_outputrules or mesecon:get_any_outputrules (outputnode)
local inputrules = mesecon:get_any_inputrules (inputnode)
if not outputrules or not inputrules then
return
end
for _, outputrule in ipairs(mesecon:flattenrules(outputrules)) do
-- Check if output sends to input
if mesecon:cmpPos(mesecon:addPosRule(output, outputrule), input) then
for _, inputrule in ipairs(mesecon:flattenrules(inputrules)) do
-- Check if input accepts from output
if mesecon:cmpPos(mesecon:addPosRule(input, inputrule), output) then
if inputrule.sx == nil or outputrule.sx == nil or mesecon:cmpSpecial(inputrule, outputrule) then
return true, inputrule
end
end
end
end
end
return false
end
function mesecon:rules_link_rule_all(output, rule) --output/input are positions (outputrules optional, used if node has been dug), second return value: affected input rules
local input = mesecon:addPosRule(output, rule)
local inputnode = minetest.get_node(input)
local inputrules = mesecon:get_any_inputrules (inputnode)
if not inputrules then
return {}
end
local rules = {}
for _, inputrule in ipairs(mesecon:flattenrules(inputrules)) do
-- Check if input accepts from output
if mesecon:cmpPos(mesecon:addPosRule(input, inputrule), output) then
if inputrule.sx == nil or rule.sx == nil or mesecon:cmpSpecial(inputrule, rule) then
rules[#rules+1] = inputrule
end
end
end
return rules
end
function mesecon:rules_link_rule_all_inverted(input, rule)
--local irule = mesecon:invertRule(rule)
local output = mesecon:addPosRule(input, rule)
local outputnode = minetest.get_node(output)
local outputrules = mesecon:get_any_outputrules (outputnode)
if not outputrules then
return {}
end
local rules = {}
for _, outputrule in ipairs(mesecon:flattenrules(outputrules)) do
if mesecon:cmpPos(mesecon:addPosRule(output, outputrule), input) then
if outputrule.sx == nil or rule.sx == nil or mesecon:cmpSpecial(outputrule, rule) then
rules[#rules+1] = mesecon:invertRule(outputrule)
end
end
end
return rules
end
function mesecon:rules_link_anydir(pos1, pos2)
return mesecon:rules_link(pos1, pos2) or mesecon:rules_link(pos2, pos1)
end
function mesecon:is_powered(pos, rule)
local node = minetest.get_node(pos)
local rules = mesecon:get_any_inputrules(node)
if not rules then return false end
if not rule then
for _, rule in ipairs(mesecon:flattenrules(rules)) do
local rulenames = mesecon:rules_link_rule_all_inverted(pos, rule)
for _, rname in ipairs(rulenames) do
local np = mesecon:addPosRule(pos, rname)
local nn = minetest.get_node(np)
if (mesecon:is_conductor_on (nn, mesecon:invertRule(rname)) or mesecon:is_receptor_on (nn.name)) then
return true
end
end
end
else
local rulenames = mesecon:rules_link_rule_all_inverted(pos, rule)
for _, rname in ipairs(rulenames) do
local np = mesecon:addPosRule(pos, rname)
local nn = minetest.get_node(np)
if (mesecon:is_conductor_on (nn, mesecon:invertRule(rname)) or mesecon:is_receptor_on (nn.name)) then
return true
end
end
end
return false
end
--Rules rotation Functions:
function mesecon:rotate_rules_right(rules)
local nr = {}
for i, rule in ipairs(rules) do
if rule.sx then
table.insert(nr, {
x = -rule.z,
y = rule.y,
z = rule.x,
sx = -rule.sz,
sy = rule.sy,
sz = rule.sx})
else
table.insert(nr, {
x = -rule.z,
y = rule.y,
z = rule.x})
end
end
return nr
end
function mesecon:rotate_rules_left(rules)
local nr = {}
for i, rule in ipairs(rules) do
if rule.sx then
table.insert(nr, {
x = rule.z,
y = rule.y,
z = -rule.x,
sx = rule.sz,
sy = rule.sy,
sz = -rule.sx})
else
table.insert(nr, {
x = rule.z,
y = rule.y,
z = -rule.x})
end
end
return nr
end
function mesecon:rotate_rules_down(rules)
local nr = {}
for i, rule in ipairs(rules) do
if rule.sx then
table.insert(nr, {
x = -rule.y,
y = rule.x,
z = rule.z,
sx = -rule.sy,
sy = rule.sx,
sz = rule.sz})
else
table.insert(nr, {
x = -rule.y,
y = rule.x,
z = rule.z})
end
end
return nr
end
function mesecon:rotate_rules_up(rules)
local nr = {}
for i, rule in ipairs(rules) do
if rule.sx then
table.insert(nr, {
x = rule.y,
y = -rule.x,
z = rule.z,
sx = rule.sy,
sy = -rule.sx,
sz = rule.sz})
else
table.insert(nr, {
x = rule.y,
y = -rule.x,
z = rule.z})
end
end
return nr
end