--- **AceHook-3.0** offers safe Hooking/Unhooking of functions, methods and frame scripts. -- Using AceHook-3.0 is recommended when you need to unhook your hooks again, so the hook chain isn't broken -- when you manually restore the original function. -- -- **AceHook-3.0** can be embeded into your addon, either explicitly by calling AceHook:Embed(MyAddon) or by -- specifying it as an embeded library in your AceAddon. All functions will be available on your addon object -- and can be accessed directly, without having to explicitly call AceHook itself.\\ -- It is recommended to embed AceHook, otherwise you'll have to specify a custom `self` on all calls you -- make into AceHook. -- @class file -- @name AceHook-3.0 -- @release $Id: AceHook-3.0.lua 1202 2019-05-15 23:11:22Z nevcairiel $ local ACEHOOK_MAJOR, ACEHOOK_MINOR = "AceHook-3.0", 8 local AceHook, oldminor = LibStub:NewLibrary(ACEHOOK_MAJOR, ACEHOOK_MINOR) if not AceHook then return end -- No upgrade needed AceHook.embeded = AceHook.embeded or {} AceHook.registry = AceHook.registry or setmetatable({}, {__index = function(tbl, key) tbl[key] = {} return tbl[key] end }) AceHook.handlers = AceHook.handlers or {} AceHook.actives = AceHook.actives or {} AceHook.scripts = AceHook.scripts or {} AceHook.onceSecure = AceHook.onceSecure or {} AceHook.hooks = AceHook.hooks or {} -- local upvalues local registry = AceHook.registry local handlers = AceHook.handlers local actives = AceHook.actives local scripts = AceHook.scripts local onceSecure = AceHook.onceSecure -- Lua APIs local pairs, next, type = pairs, next, type local format = string.format local assert, error = assert, error -- WoW APIs local issecurevariable, hooksecurefunc = issecurevariable, hooksecurefunc local _G = _G -- functions for later definition local donothing, createHook, hook local protectedScripts = { OnClick = true, } -- upgrading of embeded is done at the bottom of the file local mixins = { "Hook", "SecureHook", "HookScript", "SecureHookScript", "Unhook", "UnhookAll", "IsHooked", "RawHook", "RawHookScript" } -- AceHook:Embed( target ) -- target (object) - target object to embed AceHook in -- -- Embeds AceEevent into the target object making the functions from the mixins list available on target:.. function AceHook:Embed( target ) for k, v in pairs( mixins ) do target[v] = self[v] end self.embeded[target] = true -- inject the hooks table safely target.hooks = target.hooks or {} return target end -- AceHook:OnEmbedDisable( target ) -- target (object) - target object that is being disabled -- -- Unhooks all hooks when the target disables. -- this method should be called by the target manually or by an addon framework function AceHook:OnEmbedDisable( target ) target:UnhookAll() end function createHook(self, handler, orig, secure, failsafe) local uid local method = type(handler) == "string" if failsafe and not secure then -- failsafe hook creation uid = function(...) if actives[uid] then if method then self[handler](self, ...) else handler(...) end end return orig(...) end -- /failsafe hook else -- all other hooks uid = function(...) if actives[uid] then if method then return self[handler](self, ...) else return handler(...) end elseif not secure then -- backup on non secure return orig(...) end end -- /hook end return uid end function donothing() end function hook(self, obj, method, handler, script, secure, raw, forceSecure, usage) if not handler then handler = method end -- These asserts make sure AceHooks's devs play by the rules. assert(not script or type(script) == "boolean") assert(not secure or type(secure) == "boolean") assert(not raw or type(raw) == "boolean") assert(not forceSecure or type(forceSecure) == "boolean") assert(usage) -- Error checking Battery! if obj and type(obj) ~= "table" then error(format("%s: 'object' - nil or table expected got %s", usage, type(obj)), 3) end if type(method) ~= "string" then error(format("%s: 'method' - string expected got %s", usage, type(method)), 3) end if type(handler) ~= "string" and type(handler) ~= "function" then error(format("%s: 'handler' - nil, string, or function expected got %s", usage, type(handler)), 3) end if type(handler) == "string" and type(self[handler]) ~= "function" then error(format("%s: 'handler' - Handler specified does not exist at self[handler]", usage), 3) end if script then if not obj or not obj.GetScript or not obj:HasScript(method) then error(format("%s: You can only hook a script on a frame object", usage), 3) end if not secure and obj.IsProtected and obj:IsProtected() and protectedScripts[method] then error(format("Cannot hook secure script %q; Use SecureHookScript(obj, method, [handler]) instead.", method), 3) end else local issecure if obj then issecure = onceSecure[obj] and onceSecure[obj][method] or issecurevariable(obj, method) else issecure = onceSecure[method] or issecurevariable(method) end if issecure then if forceSecure then if obj then onceSecure[obj] = onceSecure[obj] or {} onceSecure[obj][method] = true else onceSecure[method] = true end elseif not secure then error(format("%s: Attempt to hook secure function %s. Use `SecureHook' or add `true' to the argument list to override.", usage, method), 3) end end end local uid if obj then uid = registry[self][obj] and registry[self][obj][method] else uid = registry[self][method] end if uid then if actives[uid] then -- Only two sane choices exist here. We either a) error 100% of the time or b) always unhook and then hook -- choice b would likely lead to odd debuging conditions or other mysteries so we're going with a. error(format("Attempting to rehook already active hook %s.", method)) end if handlers[uid] == handler then -- turn on a decative hook, note enclosures break this ability, small memory leak actives[uid] = true return elseif obj then -- is there any reason not to call unhook instead of doing the following several lines? if self.hooks and self.hooks[obj] then self.hooks[obj][method] = nil end registry[self][obj][method] = nil else if self.hooks then self.hooks[method] = nil end registry[self][method] = nil end handlers[uid], actives[uid], scripts[uid] = nil, nil, nil uid = nil end local orig if script then orig = obj:GetScript(method) or donothing elseif obj then orig = obj[method] else orig = _G[method] end if not orig then error(format("%s: Attempting to hook a non existing target", usage), 3) end uid = createHook(self, handler, orig, secure, not (raw or secure)) if obj then self.hooks[obj] = self.hooks[obj] or {} registry[self][obj] = registry[self][obj] or {} registry[self][obj][method] = uid if not secure then self.hooks[obj][method] = orig end if script then if not secure then obj:SetScript(method, uid) else obj:HookScript(method, uid) end else if not secure then obj[method] = uid else hooksecurefunc(obj, method, uid) end end else registry[self][method] = uid if not secure then _G[method] = uid self.hooks[method] = orig else hooksecurefunc(method, uid) end end actives[uid], handlers[uid], scripts[uid] = true, handler, script and true or nil end --- Hook a function or a method on an object. -- The hook created will be a "safe hook", that means that your handler will be called -- before the hooked function ("Pre-Hook"), and you don't have to call the original function yourself, -- however you cannot stop the execution of the function, or modify any of the arguments/return values.\\ -- This type of hook is typically used if you need to know if some function got called, and don't want to modify it. -- @paramsig [object], method, [handler], [hookSecure] -- @param object The object to hook a method from -- @param method If object was specified, the name of the method, or the name of the function to hook. -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked function) -- @param hookSecure If true, AceHook will allow hooking of secure functions. -- @usage -- -- create an addon with AceHook embeded -- MyAddon = LibStub("AceAddon-3.0"):NewAddon("HookDemo", "AceHook-3.0") -- -- function MyAddon:OnEnable() -- -- Hook ActionButton_UpdateHotkeys, overwriting the secure status -- self:Hook("ActionButton_UpdateHotkeys", true) -- end -- -- function MyAddon:ActionButton_UpdateHotkeys(button, type) -- print(button:GetName() .. " is updating its HotKey") -- end function AceHook:Hook(object, method, handler, hookSecure) if type(object) == "string" then method, handler, hookSecure, object = object, method, handler, nil end if handler == true then handler, hookSecure = nil, true end hook(self, object, method, handler, false, false, false, hookSecure or false, "Usage: Hook([object], method, [handler], [hookSecure])") end --- RawHook a function or a method on an object. -- The hook created will be a "raw hook", that means that your handler will completly replace -- the original function, and your handler has to call the original function (or not, depending on your intentions).\\ -- The original function will be stored in `self.hooks[object][method]` or `self.hooks[functionName]` respectively.\\ -- This type of hook can be used for all purposes, and is usually the most common case when you need to modify arguments -- or want to control execution of the original function. -- @paramsig [object], method, [handler], [hookSecure] -- @param object The object to hook a method from -- @param method If object was specified, the name of the method, or the name of the function to hook. -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked function) -- @param hookSecure If true, AceHook will allow hooking of secure functions. -- @usage -- -- create an addon with AceHook embeded -- MyAddon = LibStub("AceAddon-3.0"):NewAddon("HookDemo", "AceHook-3.0") -- -- function MyAddon:OnEnable() -- -- Hook ActionButton_UpdateHotkeys, overwriting the secure status -- self:RawHook("ActionButton_UpdateHotkeys", true) -- end -- -- function MyAddon:ActionButton_UpdateHotkeys(button, type) -- if button:GetName() == "MyButton" then -- -- do stuff here -- else -- self.hooks.ActionButton_UpdateHotkeys(button, type) -- end -- end function AceHook:RawHook(object, method, handler, hookSecure) if type(object) == "string" then method, handler, hookSecure, object = object, method, handler, nil end if handler == true then handler, hookSecure = nil, true end hook(self, object, method, handler, false, false, true, hookSecure or false, "Usage: RawHook([object], method, [handler], [hookSecure])") end --- SecureHook a function or a method on an object. -- This function is a wrapper around the `hooksecurefunc` function in the WoW API. Using AceHook -- extends the functionality of secure hooks, and adds the ability to unhook once the hook isn't -- required anymore, or the addon is being disabled.\\ -- Secure Hooks should be used if the secure-status of the function is vital to its function, -- and taint would block execution. Secure Hooks are always called after the original function was called -- ("Post Hook"), and you cannot modify the arguments, return values or control the execution. -- @paramsig [object], method, [handler] -- @param object The object to hook a method from -- @param method If object was specified, the name of the method, or the name of the function to hook. -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked function) function AceHook:SecureHook(object, method, handler) if type(object) == "string" then method, handler, object = object, method, nil end hook(self, object, method, handler, false, true, false, false, "Usage: SecureHook([object], method, [handler])") end --- Hook a script handler on a frame. -- The hook created will be a "safe hook", that means that your handler will be called -- before the hooked script ("Pre-Hook"), and you don't have to call the original function yourself, -- however you cannot stop the execution of the function, or modify any of the arguments/return values.\\ -- This is the frame script equivalent of the :Hook safe-hook. It would typically be used to be notified -- when a certain event happens to a frame. -- @paramsig frame, script, [handler] -- @param frame The Frame to hook the script on -- @param script The script to hook -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked script) -- @usage -- -- create an addon with AceHook embeded -- MyAddon = LibStub("AceAddon-3.0"):NewAddon("HookDemo", "AceHook-3.0") -- -- function MyAddon:OnEnable() -- -- Hook the OnShow of FriendsFrame -- self:HookScript(FriendsFrame, "OnShow", "FriendsFrameOnShow") -- end -- -- function MyAddon:FriendsFrameOnShow(frame) -- print("The FriendsFrame was shown!") -- end function AceHook:HookScript(frame, script, handler) hook(self, frame, script, handler, true, false, false, false, "Usage: HookScript(object, method, [handler])") end --- RawHook a script handler on a frame. -- The hook created will be a "raw hook", that means that your handler will completly replace -- the original script, and your handler has to call the original script (or not, depending on your intentions).\\ -- The original script will be stored in `self.hooks[frame][script]`.\\ -- This type of hook can be used for all purposes, and is usually the most common case when you need to modify arguments -- or want to control execution of the original script. -- @paramsig frame, script, [handler] -- @param frame The Frame to hook the script on -- @param script The script to hook -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked script) -- @usage -- -- create an addon with AceHook embeded -- MyAddon = LibStub("AceAddon-3.0"):NewAddon("HookDemo", "AceHook-3.0") -- -- function MyAddon:OnEnable() -- -- Hook the OnShow of FriendsFrame -- self:RawHookScript(FriendsFrame, "OnShow", "FriendsFrameOnShow") -- end -- -- function MyAddon:FriendsFrameOnShow(frame) -- -- Call the original function -- self.hooks[frame].OnShow(frame) -- -- Do our processing -- -- .. stuff -- end function AceHook:RawHookScript(frame, script, handler) hook(self, frame, script, handler, true, false, true, false, "Usage: RawHookScript(object, method, [handler])") end --- SecureHook a script handler on a frame. -- This function is a wrapper around the `frame:HookScript` function in the WoW API. Using AceHook -- extends the functionality of secure hooks, and adds the ability to unhook once the hook isn't -- required anymore, or the addon is being disabled.\\ -- Secure Hooks should be used if the secure-status of the function is vital to its function, -- and taint would block execution. Secure Hooks are always called after the original function was called -- ("Post Hook"), and you cannot modify the arguments, return values or control the execution. -- @paramsig frame, script, [handler] -- @param frame The Frame to hook the script on -- @param script The script to hook -- @param handler The handler for the hook, a funcref or a method name. (Defaults to the name of the hooked script) function AceHook:SecureHookScript(frame, script, handler) hook(self, frame, script, handler, true, true, false, false, "Usage: SecureHookScript(object, method, [handler])") end --- Unhook from the specified function, method or script. -- @paramsig [obj], method -- @param obj The object or frame to unhook from -- @param method The name of the method, function or script to unhook from. function AceHook:Unhook(obj, method) local usage = "Usage: Unhook([obj], method)" if type(obj) == "string" then method, obj = obj, nil end if obj and type(obj) ~= "table" then error(format("%s: 'obj' - expecting nil or table got %s", usage, type(obj)), 2) end if type(method) ~= "string" then error(format("%s: 'method' - expeting string got %s", usage, type(method)), 2) end local uid if obj then uid = registry[self][obj] and registry[self][obj][method] else uid = registry[self][method] end if not uid or not actives[uid] then -- Declining to error on an unneeded unhook since the end effect is the same and this would just be annoying. return false end actives[uid], handlers[uid] = nil, nil if obj then registry[self][obj][method] = nil registry[self][obj] = next(registry[self][obj]) and registry[self][obj] or nil -- if the hook reference doesnt exist, then its a secure hook, just bail out and dont do any unhooking if not self.hooks[obj] or not self.hooks[obj][method] then return true end if scripts[uid] and obj:GetScript(method) == uid then -- unhooks scripts obj:SetScript(method, self.hooks[obj][method] ~= donothing and self.hooks[obj][method] or nil) scripts[uid] = nil elseif obj and self.hooks[obj] and self.hooks[obj][method] and obj[method] == uid then -- unhooks methods obj[method] = self.hooks[obj][method] end self.hooks[obj][method] = nil self.hooks[obj] = next(self.hooks[obj]) and self.hooks[obj] or nil else registry[self][method] = nil -- if self.hooks[method] doesn't exist, then this is a SecureHook, just bail out if not self.hooks[method] then return true end if self.hooks[method] and _G[method] == uid then -- unhooks functions _G[method] = self.hooks[method] end self.hooks[method] = nil end return true end --- Unhook all existing hooks for this addon. function AceHook:UnhookAll() for key, value in pairs(registry[self]) do if type(key) == "table" then for method in pairs(value) do self:Unhook(key, method) end else self:Unhook(key) end end end --- Check if the specific function, method or script is already hooked. -- @paramsig [obj], method -- @param obj The object or frame to unhook from -- @param method The name of the method, function or script to unhook from. function AceHook:IsHooked(obj, method) -- we don't check if registry[self] exists, this is done by evil magicks in the metatable if type(obj) == "string" then if registry[self][obj] and actives[registry[self][obj]] then return true, handlers[registry[self][obj]] end else if registry[self][obj] and registry[self][obj][method] and actives[registry[self][obj][method]] then return true, handlers[registry[self][obj][method]] end end return false, nil end --- Upgrade our old embeded for target, v in pairs( AceHook.embeded ) do AceHook:Embed( target ) end