vanilla-wow-addons – Rev 1

Subversion Repositories:
Rev:
--[[
Name: AceHook-2.0
Revision: $Rev: 11577 $
Developed by: The Ace Development Team (http://www.wowace.com/index.php/The_Ace_Development_Team)
Inspired By: Ace 1.x by Turan (turan@gryphon.com)
Website: http://www.wowace.com/
Documentation: http://www.wowace.com/index.php/AceHook-2.0
SVN: http://svn.wowace.com/root/trunk/Ace2/AceHook-2.0
Description: Mixin to allow for safe hooking of functions, methods, and scripts.
Dependencies: AceLibrary, AceOO-2.0
]]

local MAJOR_VERSION = "AceHook-2.0"
local MINOR_VERSION = "$Revision: 11577 $"

-- This ensures the code is only executed if the libary doesn't already exist, or is a newer version
if not AceLibrary then error(MAJOR_VERSION .. " requires AceLibrary.") end
if not AceLibrary:IsNewVersion(MAJOR_VERSION, MINOR_VERSION) then return end

if not AceLibrary:HasInstance("AceOO-2.0") then error(MAJOR_VERSION .. " requires AceOO-2.0") end

--[[---------------------------------------------------------------------------------
  Create the library object
----------------------------------------------------------------------------------]]

local AceOO = AceLibrary:GetInstance("AceOO-2.0")
local AceHook = AceOO.Mixin {
                                                                "Hook",
                                                                "Unhook",
                                                                "UnhookAll",
                                                                "HookReport",
                                                                "IsHooked",
                                                                "HookScript",
                                                        }

local table_setn
do
        local version = GetBuildInfo()
        if string.find(version, "^2%.") then
                -- 2.0.0
                table_setn = function() end
        else
                table_setn = table.setn
        end
end

--[[---------------------------------------------------------------------------------
  Library Definitions
----------------------------------------------------------------------------------]]

local protFuncs = {
        CameraOrSelectOrMoveStart = true,       CameraOrSelectOrMoveStop = true,
        TurnOrActionStart = true,                       TurnOrActionStop = true,
        PitchUpStart = true,                            PitchUpStop = true,
        PitchDownStart = true,                          PitchDownStop = true,
        MoveBackwardStart = true,                       MoveBackwardStop = true,
        MoveForwardStart = true,                        MoveForwardStop = true,
        Jump = true,                                            StrafeLeftStart = true,
        StrafeLeftStop = true,                          StrafeRightStart = true,
        StrafeRightStop = true,                         ToggleMouseMove = true,
        ToggleRun = true,                                       TurnLeftStart = true,
        TurnLeftStop = true,                            TurnRightStart = true,
        TurnRightStop = true,
}

local _G = getfenv(0)

local handlers, funcs, scripts, actives

--[[---------------------------------------------------------------------------------
  Private definitions (Not exposed)
----------------------------------------------------------------------------------]]

--[[----------------------------------------------------------------------
        _debug - Internal Method
-------------------------------------------------------------------------]]             
local function print(text)
        DEFAULT_CHAT_FRAME:AddMessage(text)
end

local function _debug(self, msg)
        local name = self.hooks.name
        if name then
                print(string.format("[%s]: %s", name, msg))
        else
                print(msg)
        end             
end

local new, del
do
        local list = setmetatable({}, {__mode = "k"})
        function new()
                local t = next(list)
                if not t then
                        return {}
                end
                list[t] = nil
                return t
        end
        
        function del(t)
                setmetatable(t, nil)
                table_setn(t, 0)
                for k in pairs(t) do
                        t[k] = nil
                end
                list[t] = true
        end
end

local origMetatable = {
        __call = function(self, a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                return self.orig(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
        end
}

--[[----------------------------------------------------------------------
        AceHook:_getFunctionHook- internal method
-------------------------------------------------------------------------]]             

local function _getFunctionHook(self, func, handler, orig)
        if type(handler) == "string" then
                -- The handler is a method, need to self it
                return function(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        if actives[orig] then
                                return self[handler](self, a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        else
                                return orig(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        end
                end
        else
                -- The handler is a function, just call it
                return function(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        if actives[orig] then
                                return handler(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        else
                                return orig(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                        end
                end
        end
end

--[[----------------------------------------------------------------------
        AceHook:_getMethodHook - Internal Method
-------------------------------------------------------------------------]]             
local function _getMethodHook(self, object, method, handler, orig, script)
        if type(handler) == "string" then
                -- The handler is a method, need to self it
                if script then
                        return function()
                                if actives[orig] then
                                        return self[handler](self, object)
                                else
                                        return orig()
                                end
                        end
                else
                        return function(obj,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                if actives[orig] then
                                        return self[handler](self, obj, a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                else
                                        return orig(obj, a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                end
                        end
                end
        else
                -- The handler is a function, just call it
                if script then
                        return function()
                                if actives[orig] then
                                        return handler(object)
                                else
                                        return orig()
                                end
                        end
                else
                        return function(obj,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                if actives[orig] then
                                        return handler(obj,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                else
                                        return orig(obj, a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15,a16,a17,a18,a19,a20)
                                end
                        end     
                end
        end
end

--[[----------------------------------------------------------------------
        AceHook:HookFunc - internal method.
        o You can only hook each function once from each source.
        o If there is an inactive hook for this func/handler pair, we reactivate it
        o If there is an inactive hook for another handler, we error out.
        o Looks for handler as a method of the calling class, error if not available
        o If handler is a function, it just uses it directly through the wrapper
-------------------------------------------------------------------------]]             
local function _hookFunc(self, func, handler)                                           
        local orig = _G[func]
        
        if not orig or type(orig) ~= "function" then
                _debug(self, string.format("Attempt to hook a non-existant function %q", func),3)
                return
        end
        
        if not handler then handler = func end

        if self.hooks[func] then
                local orig = self.hooks[func].orig
                -- We have an active hook from this source.  Don't multi-hook
                if actives[orig] then
                        _debug(self, string.format("%q already has an active hook from this source.", func))
                        return
                end
                -- The hook is inactive, so reactivate it
                if handlers[orig] == handler then
                        actives[orig] = true
                        return
                else
                        AceHook:error("There is a stale hook for %q can't hook or reactivate.", func)
                end
        end     
        
        if type(handler) == "string" then
                if type(self[handler]) ~= "function" then
                        AceHook:error("Could not find the the handler %q when hooking function %q", handler, func)
                end
        elseif type(handler) ~= "function" then
                AceHook:error("Could not find the handler you supplied when hooking %q", func)
        end
        
        local t = setmetatable(new(), origMetatable)
        self.hooks[func] = t
        t.orig = orig
        
        actives[orig] = true
        handlers[orig] = handler
        local newFunc = _getFunctionHook(self, func, handler, orig)
        funcs[orig] = newFunc
        
        _G[func] = newFunc
end

--[[----------------------------------------------------------------------
        AceHook:UnhookFunc - internal method
        o If you attempt to unhook a function that has never been hooked, or to unhook in a
          system that has never had a hook before, the system will error with a stack trace
        o If we own the global function, then put the original back in its place and remove
          all references to the Hooks[func] structure.
        o If we don't own the global function (we've been hooked) we deactivate the hook,
          forcing the handler to passthrough.
-------------------------------------------------------------------------]]             
local function _unhookFunc(self, func)
        if not self.hooks[func] or not funcs[self.hooks[func].orig] then
                _debug(self, string.format("Tried to unhook %q which is not currently hooked.", func))
                return
        end
        
        local orig = self.hooks[func].orig
        
        if actives[orig] then
                -- See if we own the global function
                if _G[func] == funcs[orig] then
                        _G[func] = orig
                        self.hooks[func] = del(self.hooks[func])
                        handlers[orig] = nil
                        funcs[orig] = nil
                        scripts[orig] = nil
                        actives[orig] = nil
                        -- Magically all-done
                else
                        actives[orig] = nil
                end
        end
end

--[[----------------------------------------------------------------------
        AceHook:HookMeth - Takes an optional fourth argument
        o script - Signifies whether this is a script hook or not
-------------------------------------------------------------------------]]             

local function _hookMeth(self, obj, method, handler, script)
        if not handler then handler = method end
        if (not obj or type(obj) ~= "table") then
                AceHook:error("The object you supplied could not be found, or isn't a table.")
        end
        
        if self.hooks[obj] and self.hooks[obj][method] then
                local orig = self.hooks[obj][method].orig
                -- We have an active hook from this source.  Don't multi-hook
                if actives[orig] then
                        _debug(self, string.format("%q already has an active hook from this source.", method))
                        return
                end
                -- The hook is inactive, so reactivate it.
                if handlers[orig] == handler then
                        actives[orig] = true
                        return
                else
                        AceHook:error("There is a stale hook for %q can't hook or reactivate.", method)
                end
        end
        -- We're clear to try the hook, let's make some checks first
        if type(handler) == "string" then
                if type(self[handler]) ~= "function" then
                        AceHook:error("Could not find the handler %q you supplied when hooking method %q", handler, method)
                end
        elseif type(handler) ~= "function" then
                AceHook:error("Could not find the handler you supplied when hooking method %q", method)
        end
        -- Handler has been found, so now try to find the method we're trying to hook   
        local orig
        -- Script
        if script then
                if not obj.GetScript then
                        AceHook:error("The object you supplied does not have a GetScript method.")
                end
                if not obj:HasScript(method) then
                        AceHook:error("The object you supplied doesn't allow the %q method.", method)
                end
                -- Sometimes there is not a original function for a script.
                orig = obj:GetScript(method)
                if not orig then
                        orig = function() end
                end
        -- Method
        else
                orig = obj[method]
        end
        if not orig then
                AceHook:error("Could not find the method or script %q you are trying to hook.", method)
        end
        if not self.hooks[obj] then
                self.hooks[obj] = new()
        end
        local t = setmetatable(new(), origMetatable)
        self.hooks[obj][method] = t
        t.orig = orig
        
        actives[orig] = true
        handlers[orig] = handler
        scripts[orig] = script and true or nil
        local newFunc = _getMethodHook(self, obj, method, handler, orig, script)
        funcs[orig] = newFunc
        
        if script then
                obj:SetScript(method, newFunc)
        else
                obj[method] = newFunc
        end
end     

--[[----------------------------------------------------------------------
        AceHook:UnhookMeth - Internal method
        o If you attempt to unhook a method that has never been hooked, or to unhook in a
          system that has never had a hook before, the system will error with a stack trace
        o If we own the global method, then put the original back in its place and remove
          all references to the Hooks[obj][method] structure.
        o If we don't own the global method (we've been hooked) we deactivate the hook,
          forcing the handler to passthrough.
-------------------------------------------------------------------------]]             
local function _unhookMeth(self, obj, method)
        if not self.hooks[obj] or not self.hooks[obj][method] or not funcs[self.hooks[obj][method].orig] then
                _debug(self, string.format("Attempt to unhook a method %q that is not currently hooked.", method))
                return
        end
        
        local orig = self.hooks[obj][method].orig
        
        if actives[orig] then
                -- If this is a script
                if scripts[orig] then
                        if obj:GetScript(method) == funcs[orig] then
                                -- We own the script.  Kill it.
                                obj:SetScript(method, orig)
                                self.hooks[obj][method] = del(self.hooks[obj][method])
                                handlers[orig] = nil
                                funcs[orig] = nil
                                scripts[orig] = nil
                                actives[orig] = nil
                        else
                                actives[orig] = nil
                        end
                else
                        if obj[method] == funcs[orig] then
                                -- We own the method.  Kill it.
                                obj[method] = orig
                                self.hooks[obj][method] = del(self.hooks[obj][method])
                                handlers[orig] = nil
                                funcs[orig] = nil
                                scripts[orig] = nil
                                actives[orig] = nil
                        else
                                actives[orig] = nil
                        end
                end
        end
        if not next(self.hooks[obj]) then
                -- Spank the table
                self.hooks[obj] = del(self.hooks[obj])
        end
end

function AceHook:OnInstanceInit(object)
        if not object.hooks then
                object.hooks = new()
        end
        
        local name
        
        if type(rawget(object, 'GetLibraryVersion')) == "function" then
                name = object:GetLibraryVersion()
        end
        if not name and type(object.GetName) == "function" then
                name = object:GetName()
        end
        if not name and type(object.name) == "string" then
                name = object.name
        end
        if not name then
                for k,v in pairs(_G) do
                        if v == object then
                                name = tostring(k)
                                break
                        end
                end
        end
        
        object.hooks.name = name
end

AceHook.OnManualEmbed = AceHook.OnInstanceInit

--[[----------------------------------------------------------------------
        AceHook:Hook
                self:Hook("functionName", ["handlerName" | handler])
                self:Hook(ObjectName, "Method", ["Handler" | handler])
-------------------------------------------------------------------------]]             
function AceHook:Hook(arg1, arg2, arg3)
        if type(arg1)== "string" then
                if protFuncs[arg1] then
                        if self.hooks.name then
                                AceHook:error("%s tried to hook %q, which is a Blizzard protected function.", self.hooks.name, arg1)
                        else
                                _debug(self, string.format("An Addon tried to hook %q, which is a Blizzard protected function.", arg1))
                        end
                else
                        _hookFunc(self, arg1, arg2)
                end
        else
                _hookMeth(self, arg1, arg2, arg3)
        end
end

function AceHook:HookScript(arg1, arg2, arg3)
        _hookMeth(self, arg1, arg2, arg3, true)
end

--[[----------------------------------------------------------------------
        AceHook:IsHooked()
                self:Hook("functionName")
                self:Hook(ObjectName, "Method")
                
                Returns whether or not the given function is hooked in the current      
                namespace.  A hooked, but inactive function is considered NOT
                hooked in this context.
-------------------------------------------------------------------------]]             
function AceHook:IsHooked(obj, method)
        if method and obj then
                if self.hooks and self.hooks[obj] and self.hooks[obj][method] and actives[self.hooks[obj][method].orig] then
                        return true, handlers[self.hooks[obj][method].orig]
                end
        else
                if self.hooks and self.hooks[obj] and actives[self.hooks[obj].orig] then
                        return true, handlers[self.hooks[obj].orig]
                end
        end
        
        return false, nil
end

--[[----------------------------------------------------------------------
        AceHook:Unhook
                self:Unhook("functionName")
                self:Unhook(ObjectName, "Method")
-------------------------------------------------------------------------]]             
function AceHook:Unhook(arg1, arg2)
        if type(arg1) == "string" then
                _unhookFunc(self, arg1)
        else
                _unhookMeth(self, arg1, arg2)
        end
end                     

--[[----------------------------------------------------------------------
        AceHook:UnhookAll - Unhooks all active hooks from the calling source
-------------------------------------------------------------------------]]             
function AceHook:UnhookAll()
        for key, value in pairs(self.hooks) do
                if type(key) == "table" then
                        for method in pairs(value) do
                                self:Unhook(key, method)
                        end
                else
                        self:Unhook(key)
                end
        end
end


function AceHook:OnEmbedDisable(target)
        self.UnhookAll(target)
end
        
--[[----------------------------------------------------------------------
        AceHook:HookReport - Lists registered hooks from this source
-------------------------------------------------------------------------]]             

function AceHook:HookReport()
        _debug(self, "This is a list of all active hooks for this object:")
        if not self.hooks then _debug(self, "No registered hooks.") return end

        for key, value in pairs(self.hooks) do
                if type(value) == "table" then
                        for method in pairs(value) do
                                _debug(self, string.format("key: %s method: %q |cff%s|r", tostring(key), method, self.hooks[key][method].active and "00ff00Active" or "ffff00Inactive"))
                        end
                else
                        _debug(self, string.format("key: %s value: %q |cff%s|r", tostring(key), tostring(value), self.hooks[key].active and "00ff00Active" or "ffff00Inactive"))
                end
        end
end

--[[---------------------------------------------------------------------------------
  Stub and Library registration
----------------------------------------------------------------------------------]]

local function activate(self, oldLib, oldDeactivate)
        AceHook = self
        
        AceHook.super.activate(self, oldLib, oldDeactivate)
        
        if oldLib then
                self.handlers = oldLib.handlers
                self.funcs = oldLib.funcs
                self.scripts = oldLib.scripts
                self.actives = oldLib.actives
        end
        
        if not self.handlers then
                self.handlers = {}
        end
        if not self.funcs then
                self.funcs = {}
        end
        if not self.scripts then
                self.scripts = {}
        end
        if not self.actives then
                self.actives = {}
        end
        
        handlers = self.handlers
        funcs = self.funcs
        scripts = self.scripts
        actives = self.actives
        
        if oldDeactivate then
                oldDeactivate(oldLib)
        end
end

AceLibrary:Register(AceHook, MAJOR_VERSION, MINOR_VERSION, activate)