skynet inject address file.lua

inject d test/inject_fuck.lua　　-- d 是服务的 handle

拿 simpledb.lua 举例，修改如下

 local skynet = require "skynet"
 require "skynet.manager"    -- import skynet.register
 local db = {}

 local command = {}

 local i =
 local str = "abc"
 local t = {}

 function command.fuck()
     return i, str, t
 end

 skynet.info_func(function()
     return command.fuck()
 end)

 function command.GET(key)
     return db[key]
 end

 function command.SET(key, value)
     local last = db[key]
     db[key] = value
     return last
 end

 skynet.start(function()
     skynet.dispatch("lua", function(session, address, cmd, ...)
         local f = command[string.upper(cmd)]
         if f then
             skynet.ret(skynet.pack(f(...)))
         else
             error(string.format("Unknown command %s", tostring(cmd)))
         end
     end)
     skynet.register "SIMPLEDB"
 end)

添加了 fuck 函数，并设置 info_func。

设置 info_func 主要用来在 debug console 中方便用 info d 来查看 inject 的结果

下面是 inject_fuck.lua

 if not _P then
     print "inject error!"
     return
 end

 local function getuv(f)
     local i =
     local ups = {}
     while true do
         local name, value = debug.getupvalue(f, i)
         if not name then
             break
         end
         ups[name] = { i, value }
         i = i +
     end
     return ups
 end

 local function uvjoin(f, old_f, old_uv)
     local i =
     while true do
         local name, value = debug.getupvalue(f, i)
         if not name then
             break
         end
         if old_uv[name] then
             debug.upvaluejoin(f, i, old_f, old_uv[name][])
         end
         i = i +
     end
 end

 local command = _P.lua.command

 local func = command.fuck
 local old_uv = getuv(func)
 for k,v in pairs(old_uv) do
     print(k,v[])
 end

 print("  ---  ")

 local t
 local i
 local str
 function command.fuck()
     return str, t, i
 end

 uvjoin(command.fuck, func, old_uv)
 -- debug.setupvalue( command.fuck, 1, 35 )

1. 取出原 fuck 函数的所有 upvalue

2. 然后关联到新的 fuck 函数

_P 内存的 key/value 其实就是 skynet.lua 里 14 行 proto 中的 name 和 dispatch 的 upvalue

 local c = require "skynet.core"
 local tostring = tostring
 local tonumber = tonumber
 local coroutine = coroutine
 local assert = assert
 local pairs = pairs
 local pcall = pcall

 local profile = require "profile"

 local coroutine_resume = profile.resume
 local coroutine_yield = profile.yield

 local proto = {}
 local skynet = {
     -- read skynet.h
     PTYPE_TEXT = ,
     PTYPE_RESPONSE = ,
     PTYPE_MULTICAST = ,
     PTYPE_CLIENT = ,
     PTYPE_SYSTEM = ,
     PTYPE_HARBOR = ,
     PTYPE_SOCKET = ,
     PTYPE_ERROR = ,
     PTYPE_QUEUE = ,    -- used in deprecated mqueue, use skynet.queue instead
     PTYPE_DEBUG = ,
     PTYPE_LUA = ,
     PTYPE_SNAX = ,
 }

 ---

再看 simpledb.lua 的例子，文件中 disptch 的 upvalue 有两个，command 和 skynet

所以 _P.lua.command 就是文件中的 command，_P.lua.skynet 就是 skynet

在 debug console 用 inject 命令时要格外小心。。