luahotupdate.lua

local HU = {}

function HU.Init(UpdateListFile, RootPath, FailNotify, ENV)
  HU.UpdateListFile = UpdateListFile
  HU.HUMap = {}
  HU.FileMap = {}
  HU.NotifyFunc = FailNotify
  HU.OldCode = {}
  HU.ChangedFuncList = {}
  HU.VisitedSig = {}
  HU.FakeENV = nil
  HU.ENV = ENV or _G
  HU.InitFileMap(RootPath)
  HU.FakeT = HU.InitFakeTable()
  HU.InitProtection()
  HU.ALL = false
end

function HU.FailNotify(...)
  if HU.NotifyFunc then HU.NotifyFunc(...) end
end
function HU.DebugNofity(...)
  if HU.DebugNofityFunc then HU.DebugNofityFunc(...) end
end

function HU.InitFileMap(RootPath)
  for _, rootpath in pairs(RootPath) do
    local file = io.popen("dir /S/B /A:A "..rootpath)
    io.input(file)
    for line in io.lines() do
        local FileName = string.match(line,".*\\(.*)%.lua")
          if FileName ~= nil then
              if HU.FileMap[FileName] == nil then
                HU.FileMap[FileName] = {}
            end
            local luapath = string.sub(line, #rootpath+2, #line-4)
        luapath = string.gsub(luapath, "\\", ".")
            table.insert(HU.FileMap[FileName], {SysPath = line, LuaPath = luapath})
        end
      end
      file:close()
  end
end

function HU.InitFakeTable()
  local meta = {}
  HU.Meta = meta
  local function FakeT() return setmetatable({}, meta) end
  local function EmptyFunc() end
  local function pairs() return EmptyFunc end  
  local function setmetatable(t, metaT)
    HU.MetaMap[t] = metaT 
    return t
  end
  function meta.__index(t, k)
    if k == "setmetatable" then
      return setmetatable
    elseif k == "pairs" or k == "ipairs" then
      return pairs
    elseif k == "next" then
      return EmptyFunc
    else
      return FakeT() 
    end
  end
  function meta.__newindex(t, k, v) rawset(t, k, v) end
  function meta.__call() return FakeT(), FakeT(), FakeT() end
  function meta.__add() return meta.__call() end
  function meta.__sub() return meta.__call() end
  function meta.__mul() return meta.__call() end
  function meta.__div() return meta.__call() end
  function meta.__mod() return meta.__call() end
  function meta.__pow() return meta.__call() end
  function meta.__unm() return meta.__call() end
  function meta.__concat() return meta.__call() end
  function meta.__eq() return meta.__call() end
  function meta.__lt() return meta.__call() end
  function meta.__le() return meta.__call() end
  return FakeT
end

function HU.InitProtection()
  HU.Protection = {}
  HU.Protection[setmetatable] = true
  HU.Protection[pairs] = true
  HU.Protection[ipairs] = true
  HU.Protection[next] = true
  HU.Protection[HU] = true
  HU.Protection[HU.Meta] = true
end

function HU.Update()
  HU.AddFileFromHUList()
  HU.HotUpdateCode()
end

function HU.AddFileFromHUList()
  package.loaded[HU.UpdateListFile] = nil
  local FileList = require (HU.UpdateListFile)
  HU.ALL = false
  HU.HUMap = {}
  for _, file in pairs(FileList) do
    if file == "_ALL_" then
      HU.ALL = true
      for k, v in pairs(HU.FileMap) do
        for _, path in pairs(v) do
          HU.HUMap[path.LuaPath] = path.SysPath   
        end
      end
      return
    end
    if HU.FileMap[file] then
      for _, path in pairs(HU.FileMap[file]) do
        HU.HUMap[path.LuaPath] = path.SysPath   
      end
    else
      HU.FailNotify("HotUpdate can't not find "..file)
    end
  end
end

function HU.HotUpdateCode()
  for LuaPath, SysPath in pairs(HU.HUMap) do
    local OldObject = package.loaded[LuaPath]
    if OldObject ~= nil then
      HU.VisitedSig = {}
      HU.ChangedFuncList = {}
      local Success, NewObject = HU.BuildNewCode(SysPath, LuaPath)
      if Success then
        if type(OldObject) == type(NewObject) then
          if type(NewObject) == "table" then
            HU.UpdateAllFunction(OldObject, NewObject, LuaPath, "Main", "") 
          elseif type(NewObject) == "function" then
            HU.UpdateOneFunction(OldObject, NewObject, LuaPath, nil, "Main", "")
          end
        end
        setmetatable(HU.FakeENV, nil)
        HU.UpdateAllFunction(HU.ENV, HU.FakeENV, " ENV ", "Main", "")
        if #HU.ChangedFuncList > 0 then
          HU.Travel_G()
        end
      end
    end
  end
  collectgarbage("collect")
end 

function HU.BuildNewCode(FilePath, LuaPath)
  io.input(FilePath)
  local NewCode = io.read("*all")
  if HU.ALL and HU.OldCode[FilePath] == nil then
    HU.OldCode[FilePath] = NewCode
    return
  end
  if HU.OldCode[FilePath] == NewCode then
    io.input():close()
    return false
  end
  HU.DebugNofity(FilePath)
  io.input(FilePath)  
  local chunk = "--[["..LuaPath.."]] "
  chunk = chunk..NewCode  
  io.input():close()
  local NewFunction = loadstring(chunk)
  if not NewFunction then 
      HU.FailNotify(FilePath.." has syntax error.")   
      return false
  else
    HU.FakeENV = HU.FakeT()
    HU.MetaMap = {}
    setfenv(NewFunction, HU.FakeENV)
    local NewObject
    HU.ErrorHappen = false
    xpcall(function () NewObject = NewFunction() end, HU.ErrorHandle)
    if not HU.ErrorHappen then 
      HU.OldCode[FilePath] = NewCode
      return true, NewObject
    else
      return false
    end
  end
end

function HU.ErrorHandle(e)
  HU.FailNotify("HotUpdate Error\n"..tostring(e))
  HU.ErrorHappen = true
end

function HU.UpdateOneFunction(OldObject, NewObject, FuncName, OldTable, From, Deepth)
  if HU.Protection[OldObject] or HU.Protection[NewObject] then return end
  if OldObject == NewObject then return end
  local signature = tostring(OldObject)..tostring(NewObject)
  if HU.VisitedSig[signature] then return end
  HU.VisitedSig[signature] = true
  HU.DebugNofity(Deepth.."HU.UpdateOneFunction "..FuncName.."  from:"..From)
  if pcall(setfenv, NewObject, getfenv(OldObject)) then
    HU.UpdateUpvalue(OldObject, NewObject, FuncName, "HU.UpdateOneFunction", Deepth.."    ")
    HU.ChangedFuncList[#HU.ChangedFuncList + 1] = {OldObject, NewObject, FuncName, OldTable}
  end
end

function HU.UpdateAllFunction(OldTable, NewTable, Name, From, Deepth)
  if HU.Protection[OldTable] or HU.Protection[NewTable] then return end
  if OldTable == NewTable then return end
  local signature = tostring(OldTable)..tostring(NewTable)
  if HU.VisitedSig[signature] then return end
  HU.VisitedSig[signature] = true
  HU.DebugNofity(Deepth.."HU.UpdateAllFunction "..Name.."  from:"..From)
  for ElementName, Element in pairs(NewTable) do
    local OldElement = OldTable[ElementName]
    if type(Element) == type(OldElement) then
      if type(Element) == "function" then
        HU.UpdateOneFunction(OldElement, Element, ElementName, OldTable, "HU.UpdateAllFunction", Deepth.."    ")
      elseif type(Element) == "table" then
        HU.UpdateAllFunction(OldElement, Element, ElementName, "HU.UpdateAllFunction", Deepth.."    ")
      end
    elseif OldElement == nil and type(Element) == "function" then
      OldTable[ElementName] = Element
      setfenv(Element, HU.ENV)
    end
  end
  local OldMeta = debug.getmetatable(OldTable)  
  local NewMeta = HU.MetaMap[NewTable]
  if type(OldMeta) == "table" and type(NewMeta) == "table" then
    HU.UpdateAllFunction(OldMeta, NewMeta, Name.."'s Meta", "HU.UpdateAllFunction", Deepth.."    ")
  end
end

function HU.ResetENV(object)
  local visited = {}
  local function f(object)
    if visited[object] then return end
    visited[object] = true
    if type(object) == "function" then
      setfenv(object, HU.ENV)
    elseif type(object) == "table" then
      for k, v in pairs(object) do
        f(k);f(v)
      end
    end
  end
  f(object)
end

function HU.UpdateUpvalue(OldFunction, NewFunction, Name, From, Deepth)
  HU.DebugNofity(Deepth.."HU.UpdateUpvalue", Name, "  from:"..From)
  local OldUpvalueMap = {}
  local OldExistName = {}
  for i = 1, math.huge do
    local name, value = debug.getupvalue(OldFunction, i)
    if not name then break end
    OldUpvalueMap[name] = value
    OldExistName[name] = true
  end
  for i = 1, math.huge do
    local name, value = debug.getupvalue(NewFunction, i)
    if not name then break end
    if OldExistName[name] then
      local OldValue = OldUpvalueMap[name]
      if type(OldValue) ~= type(value) then
        debug.setupvalue(NewFunction, i, OldValue)
      elseif type(OldValue) == "function" then
        HU.UpdateOneFunction(OldValue, value, name, nil, "HU.UpdateUpvalue", Deepth.."    ")
      elseif type(OldValue) == "table" then
        HU.UpdateAllFunction(OldValue, value, name, "HU.UpdateUpvalue", Deepth.."    ")
        debug.setupvalue(NewFunction, i, OldValue)
      else
        debug.setupvalue(NewFunction, i, OldValue)
      end
    else
      HU.ResetENV(value)
    end
  end
end

function HU.Travel_G()
  local visited = {}
  visited[HU] = true
  local function f(t)
    if not t or visited[t] or HU.Protection[t] then return end
    visited[t] = true
    if type(t) == "function" then
        for i = 1, math.huge do
        local name, value = debug.getupvalue(t, i)
        if not name then break end
        f(value);f(debug.getmetatable(value))
      end
    elseif type(t) == "table" then
      for k,v in pairs(t) do
        f(k); f(debug.getmetatable(k)); f(v); f(debug.getmetatable(v))
        if type(v) == "function" or type(k) == "function" then
          for _, funcs in ipairs(HU.ChangedFuncList) do
            if v == funcs[1] then t[k] = funcs[2] end
            if k == funcs[1] then t[funcs[2]] = t[k]; t[k] = nil end
          end
        end
      end
    end
  end
  f(_G)
  local registryTable = debug.getregistry()
  for _, funcs in ipairs(HU.ChangedFuncList) do
    for k, v in pairs(registryTable) do
      if v == funcs[1] then
        registryTable[k] = funcs[2]
      end
    end
  end
  for _, funcs in ipairs(HU.ChangedFuncList) do
    if funcs[3] == "HUDebug" then funcs[4]:HUDebug() end
  end
end

return HU