local ffi = require 'ffi'
--HOOKS
local hook = {hooks = {}}
addEventHandler('onScriptTerminate', function(scr)
if scr == script.this then
for i, hook in ipairs(hook.hooks) do
if hook.status then
hook.stop()
end
end
end
end)
ffi.cdef [[
int VirtualProtect(void* lpAddress, unsigned long dwSize, unsigned long flNewProtect, unsigned long* lpflOldProtect);
]]
function hook.new(cast, callback, hook_addr, size)
jit.off(callback, true) --off jit compilation | thx FYP
local size = size or 5
local new_hook = {}
local detour_addr = tonumber(ffi.cast('intptr_t', ffi.cast('void*', ffi.cast(cast, callback))))
local void_addr = ffi.cast('void*', hook_addr)
local old_prot = ffi.new('unsigned long[1]')
local org_bytes = ffi.new('uint8_t[?]', size)
ffi.copy(org_bytes, void_addr, size)
local hook_bytes = ffi.new('uint8_t[?]', size, 0x90)
hook_bytes[0] = 0xE9
ffi.cast('uint32_t*', hook_bytes + 1)[0] = detour_addr - hook_addr - 5
new_hook.call = ffi.cast(cast, hook_addr)
new_hook.status = false
local function set_status(bool)
new_hook.status = bool
ffi.C.VirtualProtect(void_addr, size, 0x40, old_prot)
ffi.copy(void_addr, bool and hook_bytes or org_bytes, size)
ffi.C.VirtualProtect(void_addr, size, old_prot[0], old_prot)
end
new_hook.stop = function() set_status(false) end
new_hook.start = function() set_status(true) end
new_hook.start()
table.insert(hook.hooks, new_hook)
return setmetatable(new_hook, {
__call = function(self, ...)
self.stop()
local res = self.call(...)
self.start()
return res
end
})
end
--HOOKS
function blowUpPlaneHook(plane, damager, bHideExplosion)
printStringNow('~r~CPlane::BlowUpCar called', 800)
-- you can add some condition checks here
-- to make your plane explode only when you want it to
-- return blowUpPlane(plane, damager, bHideExplosion)
end
function blowUpHeliHook(heli, damager, bHideExplosion)
printStringNow('~r~CHeli::BlowUpCar called', 800)
-- actually, this hook doesn't work as it should.
-- the helicopter itself doesn't explode, but explosions
-- occur underneath it and its HP goes negative.
-- not sure what might be causing this
-- return blowUpHeli(heli, damager, bHideExplosion)
end
function main()
local blowUpPlaneAddr = 0x6CCCF0 -- CPlane::BlowUpCar
local blowUpHeliAddr = 0x6C6D30 -- CHeli::BlowUpCar
blowUpPlane = hook.new(
'void(__thiscall *)(void *plane, void *damager, bool bHideExplosion)',
blowUpPlaneHook,
blowUpPlaneAddr
)
blowUpHeli = hook.new(
'void(__thiscall *)(void *heli, void *damager, bool bHideExplosion)',
blowUpHeliHook,
blowUpHeliAddr
)
end