+++ /dev/null
---[[
-LuCI - Lua Development Framework
-
-Copyright 2009 Steven Barth <steven@midlink.org>
-
-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 nixio = require "nixio"
-local table = require "table"
-local uci = require "luci.model.uci"
-local os = require "os"
-local io = require "io"
-
-local pairs, require, pcall, assert, type = pairs, require, pcall, assert, type
-local ipairs, tonumber, collectgarbage = ipairs, tonumber, collectgarbage
-
-
-module "luci.lucid"
-
-local slaves = {}
-local pollt = {}
-local tickt = {}
-local tpids = {}
-local tcount = 0
-local ifaddrs = nixio.getifaddrs()
-
-cursor = uci.cursor()
-state = uci.cursor_state()
-UCINAME = "lucid"
-
-local cursor = cursor
-local state = state
-local UCINAME = UCINAME
-local SSTATE = "/tmp/.lucid_store"
-
-
---- Starts a new LuCId superprocess.
-function start()
- state:revert(UCINAME, "main")
-
- prepare()
-
- local detach = cursor:get(UCINAME, "main", "daemonize")
- if detach == "1" then
- local stat, code, msg = daemonize()
- if not stat then
- nixio.syslog("crit", "Unable to detach process: " .. msg .. "\n")
- ox.exit(2)
- end
- end
-
- state:set(UCINAME, "main", "pid", nixio.getpid())
- state:save(UCINAME)
-
- run()
-end
-
---- Returns the PID of the currently active LuCId process.
-function running()
- local pid = tonumber(state:get(UCINAME, "main", "pid"))
- return pid and nixio.kill(pid, 0) and pid
-end
-
---- Stops any running LuCId superprocess.
-function stop()
- local pid = tonumber(state:get(UCINAME, "main", "pid"))
- if pid then
- return nixio.kill(pid, nixio.const.SIGTERM)
- end
- return false
-end
-
---- Prepares the slaves, daemons and publishers, allocate resources.
-function prepare()
- local debug = tonumber((cursor:get(UCINAME, "main", "debug")))
-
- nixio.openlog("lucid", "pid", "perror")
- if debug ~= 1 then
- nixio.setlogmask("warning")
- end
-
- cursor:foreach(UCINAME, "daemon", function(config)
- if config.enabled ~= "1" then
- return
- end
-
- local key = config[".name"]
- if not config.slave then
- nixio.syslog("crit", "Daemon "..key.." is missing a slave\n")
- os.exit(1)
- else
- nixio.syslog("info", "Initializing daemon " .. key)
- end
-
- state:revert(UCINAME, key)
-
- local daemon, code, err = prepare_daemon(config)
- if daemon then
- state:set(UCINAME, key, "status", "started")
- nixio.syslog("info", "Prepared daemon " .. key)
- else
- state:set(UCINAME, key, "status", "error")
- state:set(UCINAME, key, "error", err)
- nixio.syslog("err", "Failed to initialize daemon "..key..": "..
- err .. "\n")
- end
- end)
-end
-
---- Run the superprocess if prepared before.
--- This main function of LuCId will wait for events on given file descriptors.
-function run()
- local pollint = tonumber((cursor:get(UCINAME, "main", "pollinterval")))
- local threadlimit = tonumber((cursor:get(UCINAME, "main", "threadlimit")))
-
- while true do
- local stat, code = nixio.poll(pollt, pollint)
-
- if stat and stat > 0 then
- local ok = false
- for _, polle in ipairs(pollt) do
- if polle.revents ~= 0 and polle.handler then
- ok = ok or polle.handler(polle)
- end
- end
- if not ok then
- -- Avoid high CPU usage if thread limit is reached
- nixio.nanosleep(0, 100000000)
- end
- elseif stat == 0 then
- ifaddrs = nixio.getifaddrs()
- end
-
- for _, cb in ipairs(tickt) do
- cb()
- end
-
- local pid, stat, code = nixio.wait(-1, "nohang")
- while pid and pid > 0 do
- nixio.syslog("info", "Buried thread: " .. pid)
- if tpids[pid] then
- tcount = tcount - 1
- if tpids[pid] ~= true then
- tpids[pid](pid, stat, code)
- end
- tpids[pid] = nil
- end
- pid, stat, code = nixio.wait(-1, "nohang")
- end
- end
-end
-
---- Add a file descriptor for the main loop and associate handler functions.
--- @param polle Table containing: {fd = FILE DESCRIPTOR, events = POLL EVENTS,
--- handler = EVENT HANDLER CALLBACK}
--- @see unregister_pollfd
--- @return boolean status
-function register_pollfd(polle)
- pollt[#pollt+1] = polle
- return true
-end
-
---- Unregister a file desciptor and associate handler from the main loop.
--- @param polle Poll descriptor
--- @see register_pollfd
--- @return boolean status
-function unregister_pollfd(polle)
- for k, v in ipairs(pollt) do
- if v == polle then
- table.remove(pollt, k)
- return true
- end
- end
- return false
-end
-
---- Close all registered file descriptors from main loop.
--- This is useful for forked child processes.
-function close_pollfds()
- for k, v in ipairs(pollt) do
- if v.fd and v.fd.close then
- v.fd:close()
- end
- end
-end
-
---- Register a tick function that will be called at each cycle of the main loop.
--- @param cb Callback
--- @see unregister_tick
--- @return boolean status
-function register_tick(cb)
- tickt[#tickt+1] = cb
- return true
-end
-
---- Unregister a tick function from the main loop.
--- @param cb Callback
--- @see register_tick
--- @return boolean status
-function unregister_tick(cb)
- for k, v in ipairs(tickt) do
- if v == cb then
- table.remove(tickt, k)
- return true
- end
- end
- return false
-end
-
---- Tests whether a given number of processes can be created.
--- @oaram num Processes to be created
--- @return boolean status
-function try_process(num)
- local threadlimit = tonumber((cursor:get(UCINAME, "main", "threadlimit")))
- return not threadlimit or (threadlimit - tcount) >= (num or 1)
-end
-
---- Create a new child process from a Lua function and assign a destructor.
--- @param threadcb main function of the new process
--- @param waitcb destructor callback
--- @return process identifier or nil, error code, error message
-function create_process(threadcb, waitcb)
- local threadlimit = tonumber(cursor:get(UCINAME, "main", "threadlimit"))
- if threadlimit and tcount >= threadlimit then
- nixio.syslog("warning", "Cannot create thread: process limit reached")
- return nil
- else
- collectgarbage("collect")
- end
- local pid, code, err = nixio.fork()
- if pid and pid ~= 0 then
- nixio.syslog("info", "Created thread: " .. pid)
- tpids[pid] = waitcb or true
- tcount = tcount + 1
- elseif pid == 0 then
- local code = threadcb()
- os.exit(code)
- else
- nixio.syslog("err", "Unable to fork(): " .. err)
- end
- return pid, code, err
-end
-
---- Prepare a daemon from a given configuration table.
--- @param config Configuration data.
--- @return boolean status or nil, error code, error message
-function prepare_daemon(config)
- nixio.syslog("info", "Preparing daemon " .. config[".name"])
- local modname = cursor:get(UCINAME, config.slave)
- if not modname then
- return nil, -1, "invalid slave"
- end
-
- local stat, module = pcall(require, _NAME .. "." .. modname)
- if not stat or not module.prepare_daemon then
- return nil, -2, "slave type not supported"
- end
-
- config.slave = prepare_slave(config.slave)
-
- return module.prepare_daemon(config, _M)
-end
-
---- Prepare a slave.
--- @param name slave name
--- @return table containing slave module and configuration or nil, error message
-function prepare_slave(name)
- local slave = slaves[name]
- if not slave then
- local config = cursor:get_all(UCINAME, name)
-
- local stat, module = pcall(require, config and config.entrypoint)
- if stat then
- slave = {module = module, config = config}
- end
- end
-
- if slave then
- return slave
- else
- return nil, module
- end
-end
-
---- Return a list of available network interfaces on the host.
--- @return table returned by nixio.getifaddrs()
-function get_interfaces()
- return ifaddrs
-end
-
---- Revoke process privileges.
--- @param user new user name or uid
--- @param group new group name or gid
--- @return boolean status or nil, error code, error message
-function revoke_privileges(user, group)
- if nixio.getuid() == 0 then
- return nixio.setgid(group) and nixio.setuid(user)
- end
-end
-
---- Return a secure UCI cursor.
--- @return UCI cursor
-function securestate()
- local stat = nixio.fs.stat(SSTATE) or {}
- local uid = nixio.getuid()
- if stat.type ~= "dir" or (stat.modedec % 100) ~= 0 or stat.uid ~= uid then
- nixio.fs.remover(SSTATE)
- if not nixio.fs.mkdir(SSTATE, 700) then
- local errno = nixio.errno()
- nixio.syslog("err", "Integrity check on secure state failed!")
- return nil, errno, nixio.perror(errno)
- end
- end
-
- return uci.cursor(nil, SSTATE)
-end
-
---- Daemonize the process.
--- @return boolean status or nil, error code, error message
-function daemonize()
- if nixio.getppid() == 1 then
- return
- end
-
- local pid, code, msg = nixio.fork()
- if not pid then
- return nil, code, msg
- elseif pid > 0 then
- os.exit(0)
- end
-
- nixio.setsid()
- nixio.chdir("/")
-
- local devnull = nixio.open("/dev/null", nixio.open_flags("rdwr"))
- nixio.dup(devnull, nixio.stdin)
- nixio.dup(devnull, nixio.stdout)
- nixio.dup(devnull, nixio.stderr)
-
- return true
-end
projects / project / luci.git / blobdiff