add

stratumBackend/stratumDBlib.lua

@@ -0,0 +1,137 @@
+local stratum = {}
+
+-- Source - https://stackoverflow.com/a/1579673
+-- Posted by Faisal Hanif, modified by community. See post 'Timeline' for change history
+-- Retrieved 2026-04-05, License - CC BY-SA 3.0
+
+---splits a string by a pattern
+---@param pString string
+---@param pPattern string
+---@return string[]
+local function split(pString, pPattern)
+   local Table = {}  -- NOTE: use {n = 0} in Lua-5.0
+   local fpat = "(.-)" .. pPattern
+   local last_end = 1
+   local s, e, cap = pString:find(fpat, 1)
+   while s do
+      if s ~= 1 or cap ~= "" then
+     table.insert(Table,cap)
+      end
+      last_end = e+1
+      s, e, cap = pString:find(fpat, last_end)
+   end
+   if last_end <= #pString then
+      cap = pString:sub(last_end)
+      table.insert(Table, cap)
+   end
+   return Table
+end
+
+
+
+---applys macros to code
+---@param code string
+---@return string
+function stratum.applyMacros(code,libpath)
+    local import_name = ""
+    local alphabet = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}
+    for _ = 1,10 do
+        import_name = import_name..alphabet[math.random(1,#alphabet)]
+    end
+    local import_string = "local "..import_name.." = require(\""..libpath.."\")\n"
+    local splits = split(" "..code,"%-%-#")
+    for instanceIndex = 2,#splits do
+        local instance = splits[instanceIndex]
+        local lines = split(instance:gsub("\n"," \n").." ","\n")
+        local nonSpacedLines = split(instance,"\n")
+        local contextDepth = 0
+        local finalCodeLines = {}
+        for lineIndex = 2,#lines do
+            local line = lines[lineIndex]
+            local _,dos = line:gsub("do ","")
+            local _,funcs = line:gsub("function ","")
+            local _,thens = line:gsub("then ","")
+            local _,ends = line:gsub("end ","")
+            contextDepth = contextDepth+dos+funcs+thens-ends
+            finalCodeLines[#finalCodeLines+1] = nonSpacedLines[lineIndex]
+            if contextDepth <= 0 then
+                break
+            end
+        end
+        local replaceSub = table.concat(finalCodeLines,"\n")
+        local opcount = 0
+        ---@type string
+        local funcdef = table.remove(finalCodeLines,1)
+        table.remove(finalCodeLines)
+        local body = table.concat(finalCodeLines,"\n")
+        local replace = funcdef
+
+        if nonSpacedLines[1] == "data_transform" and string.find(funcdef,"function ") then
+            funcdef,opcount = funcdef:gsub("function ",""):gsub("local ", "")
+            local defsplit = split(funcdef, "%(")
+            defsplit[2] = split(defsplit[2],"%)")[1] or "_"
+            replace = defsplit[1].." = "..import_name..".createTransform(\""..defsplit[1].."\",\"local data,"..defsplit[2].." = ...\\n"..body:gsub("\n","\\n"):gsub("\"","\\\"").."\")"
+            if opcount > 0 then
+                replace = "local "..replace
+            end
+        elseif nonSpacedLines[1] == "common_transform" and string.find(funcdef,"function ") then
+            funcdef = funcdef:gsub("function ",""):gsub("local ", "")
+            local defsplit = split(funcdef, "%(")
+            defsplit[2] = split(defsplit[2],"%)")[1] or "_"
+            replace = replaceSub.."\n"..(import_name..".createTransform(\""..defsplit[1].."\",\"local data,"..defsplit[2].." = ...\\n"..body:gsub("\n","\\n"):gsub("\"","\\\"").."\")")
+        end
+        code = code:gsub(replaceSub:gsub("([%(%)%.%%%+%-%*%?%[%]%^%$])", "%%%1"),replace)
+    end
+    return import_string..code
+end
+
+function stratum.loadTransforms(modules,libpath)
+    local file,err = package.searchpath(shell.dir(),modules)
+    if not file then
+        file,err = package.searchpath(shell.dir(),modules..".lua")
+    end
+    if not file then error("failed to find package: "..err,2) end
+    local file = fs.open(file,"r")
+    if not file then error("failed to open file",2) end
+    local contents = file.readAll()
+    file.close()
+    if not contents then error("failed to read file",2) end
+    print("applying macros")
+    contents = stratum.applyMacros(contents,libpath)
+    print("loading contents")
+    local trans, err = load(contents,"transforms","t",_ENV)
+    if not trans then error(err,2) end
+    print("running contents")
+    return trans()
+end
+
+function stratum.setBackend(backend)
+    if backend.sendMessage and backend.receiveMessage then
+        _G._STRATUMBACKEND = backend
+    end
+end
+
+function stratum.createTransform(name,func)
+    print("registering "..name)
+    local backend = _STRATUMBACKEND
+    if not backend or not (backend.sendMessage and backend.receiveMessage) then error("stratum backend not defined or defined incorrectly",2) end
+    backend.sendMessage({protocol="RegisterTransform",name=name,functionBody=func})
+    while true do
+        local message = backend.receiveMessage()
+        if message.protocol == "TransformRegistered" and message.name == name then
+            return function (...)
+                backend.sendMessage({protocol = "CallTransform", name=name,params={...}})
+                while true do
+                local message = backend.receiveMessage()
+                    if message.protocol == "TransformResult" and message.name == name then
+                        return table.unpack(message.result)
+                    elseif message.protocol == "TransformError" and message.name == name then
+                        error(message.error,2)
+                    end
+                end
+            end
+        end
+    end
+end
+
+return stratum