单消息多处理函数的实现.注册消息处理函数时可提供优先执行函数列表(即在优先执行函数列表中的函数先于正在注册的函数).

HXProtHandler.lua

--[[=============================================================================
#     FileName: HXProtHandler.lua
#         Desc: 单个消息多个处理函数带有优先级的实现
#       Author: hanxi
#        Email: hanxi.com@gmail.com
#     HomePage: http://hanxi.cnblogs.com
#      Version: 0.0.1
#   LastChange: 2013-08-26 11:42:37
#      History: 添加优先级冲突检测
=============================================================================]]
-- 全局变量
-- _GProtFuncName2Func = {  -- 绑定函数名和函数
--  funcName1 = func1,
--  funcName2 = func2,
-- }
-- _GProtHandlers = {       -- 绑定协议号和函数名
--  [protId] = {            -- key为函数名,preFuncNames为优先执行函数名组
--      funcName1 = preFuncNames,
--      funcName2 = preFuncNames,
--  }
-- }
-- preFuncNames = {         -- 收到消息时,优先执行下面的函数
--  preFuncName1,preFuncName2,
-- }
-- 按优先级排序后的handler函数
-- _GProtHandlersForExec = {
--  [protId] = {func1,func2}
-- }

function log (...)
    print(...)
end

-- @param:protId       -- 协议Id
-- @param:func         -- 注册函数
-- @param:funcName     -- 注册函数名
-- @param:preFuncNames -- 优先执行函数名组
function HXProtRegHandler(protId,func,funcName,preFuncNames)
    if not protId or type(func)~="function" or type(funcName)~="string" then
        error("HXProtRegHandler 参数错误")
        return -1
    end
    if not preFuncNames then
        preFuncNames = {}
    end
    if not _GProtHandlers then
        _GProtHandlers={}
    end
    if not _GProtHandlers[protId] then
        _GProtHandlers[protId]={}
    end
    _GProtHandlers[protId][funcName] = preFuncNames

    if not _GProtFuncName2Func then
        _GProtFuncName2Func = {}
    end
    _GProtFuncName2Func[funcName] = func

    if type(_GProtHandlersForExec)=="table" then
        -- 用于热更新的时候,重置_GProtHandlersForExec
        _GProtHandlersForExec[protId] = nil
    end
end

-- 查找表中是否存在value
function table.find(tab, value)
    for k,v in pairs(tab) do
        if v==value then
            return k
        end
    end
    return -1
end

-- 查找表中所有存在的value
function table.findall(tab, value)
    local result = {}
    for k,v in pairs(tab) do
        if v==value then
            table.insert(result,k)
        end
    end
    if #result==0 then
        return -1
    end
    return result
end

-- 收到协议id为protId的消息时进入此函数处理
HXProtExecHandler = function (fd,protId,prot)
    local handlers = _GProtHandlers[protId]
    if not handlers then
        log("ERROR: 收到为注册的协议.protId=",protId)
        for k,v in pairs(prot) do
            log(k,v)
        end
        return
    end
    if not _GProtHandlersForExec then
        _GProtHandlersForExec = {}
    end
    if not _GProtHandlersForExec[protId] then
        _GProtHandlersForExec[protId] = {}
        for funcName,preFuncNames in pairs(handlers) do
            log("["..funcName.."]")
            for k,v in pairs(preFuncNames) do
                log("--",v)
            end
            local pos = table.find(_GProtHandlersForExec[protId],funcName)
            log("pos",pos,funcName)
            if pos==-1 then
                table.insert(_GProtHandlersForExec[protId],funcName)
                pos = #_GProtHandlersForExec[protId]
            end
            for _,preFuncName in ipairs(preFuncNames) do
                local p = table.find(_GProtHandlersForExec[protId],preFuncName)
                log("p",p,preFuncName)
                if p==-1 then
                    table.insert(_GProtHandlersForExec[protId],pos,preFuncName)
                elseif p>pos then
                    log("优先函数处理有冲突:"..funcName..","..preFuncName)
                end
            end
        end
    end
    for k,funcName in ipairs(_GProtHandlersForExec[protId]) do
        local func = _GProtFuncName2Func[funcName]
        if not func then
            log("协议protId="..protId..",有未实现的handler函数,funcName="..funcName)
        else
            func(fd,prot)
        end
    end
end

-- test
function f1(fd,prot)
    log("f1",prot)
end
-- 注册处理函数
HXProtRegHandler(1,f1,"f1",{"f2","f3"})
function f2(fd,prot)
    log("f2",prot)
end
HXProtRegHandler(1,f2,"f2",{"f1"})
function f3(fd,prot)
    log("f3",prot)
end
HXProtRegHandler(1,f3,"f3",{"f1","f4"})
function f4(fd,prot)
    log("f4",prot)
end
HXProtRegHandler(1,f4,"f4",{"f2","f3"})
function f5(fd,prot)
    log("f5",prot)
end
HXProtRegHandler(1,f5,"f5",{"f7"})

-- 假设收到消息1
HXProtExecHandler(1,1,"prot")