Rework LuCI build system

[project/luci.git] / modules / luci-base / luasrc / ccache.lua

diff --git a/modules/luci-base/luasrc/ccache.lua b/modules/luci-base/luasrc/ccache.lua
new file mode 100644 (file)
index 0000000..56ccbc3
--- /dev/null
+++ b/modules/luci-base/luasrc/ccache.lua
@@ -0,0 +1,87 @@
+--[[
+LuCI - Lua Configuration Interface
+
+Copyright 2008 Steven Barth <steven@midlink.org>
+Copyright 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+]]--
+
+local io = require "io"
+local fs = require "nixio.fs"
+local util = require "luci.util"
+local nixio = require "nixio"
+local debug = require "debug"
+local string = require "string"
+local package = require "package"
+
+local type, loadfile = type, loadfile
+
+
+module "luci.ccache"
+
+function cache_ondemand(...)
+       if debug.getinfo(1, 'S').source ~= "=?" then
+               cache_enable(...)
+       end
+end
+
+function cache_enable(cachepath, mode)
+       cachepath = cachepath or "/tmp/luci-modulecache"
+       mode = mode or "r--r--r--"
+
+       local loader = package.loaders[2]
+       local uid    = nixio.getuid()
+
+       if not fs.stat(cachepath) then
+               fs.mkdir(cachepath)
+       end
+
+       local function _encode_filename(name)
+               local encoded = ""
+               for i=1, #name do
+                       encoded = encoded .. ("%2X" % string.byte(name, i))
+               end
+               return encoded
+       end
+
+       local function _load_sane(file)
+               local stat = fs.stat(file)
+               if stat and stat.uid == uid and stat.modestr == mode then
+                       return loadfile(file)
+               end
+       end
+
+       local function _write_sane(file, func)
+               if nixio.getuid() == uid then
+                       local fp = io.open(file, "w")
+                       if fp then
+                               fp:write(util.get_bytecode(func))
+                               fp:close()
+                               fs.chmod(file, mode)
+                       end
+               end
+       end
+
+       package.loaders[2] = function(mod)
+               local encoded = cachepath .. "/" .. _encode_filename(mod)
+               local modcons = _load_sane(encoded)
+               
+               if modcons then
+                       return modcons
+               end
+
+               -- No cachefile
+               modcons = loader(mod)
+               if type(modcons) == "function" then
+                       _write_sane(encoded, modcons)
+               end
+               return modcons
+       end
+end