From: Johannes Truschnigg <johannes@truschnigg.info>
Date: Sun, 26 Jun 2022 18:13:57 +0000 (+0200)
Subject: Import netconsole-rx lua application and procd init script
X-Git-Url: https://johannes.truschnigg.info/gitweb/?a=commitdiff_plain;h=7b3f43de1ba50616fb9f592e0f212045b0f298a2;p=netconsole-rx

Import netconsole-rx lua application and procd init script
---

7b3f43de1ba50616fb9f592e0f212045b0f298a2
diff --git a/netconsole-rx.init b/netconsole-rx.init
new file mode 100755
index 0000000..bb47912
--- /dev/null
+++ b/netconsole-rx.init
@@ -0,0 +1,23 @@
+#!/bin/sh /etc/rc.common
+# Copyright (C) 2006-2011 OpenWrt.org
+
+START=98
+
+USE_PROCD=1
+PROG=/root/netconsole-rx.lua
+
+OUTFILE=/tmp/netconsole.out
+PIDFILE=/tmp/netconsole.pid
+LISTENPORT=1514
+
+start_service() {
+	procd_open_instance "netconsole_${LISTENPORT}"
+	procd_set_param command "$PROG" listenport="${LISTENPORT}" outfile="${OUTFILE}" pidfile="${PIDFILE}"
+	procd_set_param stderr 1
+	procd_close_instance
+}
+
+reload_service() {
+	stop
+	start
+}
diff --git a/netconsole-rx.lua b/netconsole-rx.lua
new file mode 100755
index 0000000..fcd2407
--- /dev/null
+++ b/netconsole-rx.lua
@@ -0,0 +1,113 @@
+#!/usr/bin/env lua
+local socket = require("socket")
+local udpl = assert(socket.udp())
+
+
+function getpid()
+  local line
+  statfp = io.open("/proc/self/stat", "r")
+  if statfp == nil then
+    return "--unknown--"
+  end
+  line = statfp:read()
+  return line:match("%d+")
+end
+
+
+function args_parse()
+  local opt
+  for _, opt in ipairs(arg) do
+    if opt:find("port=", 1, true) then
+      listenport = tonumber(opt:match("%d+$", 5))
+    elseif opt:find("pidfile=", 1, true) then
+      pidfile = opt:match("[^%c]+", 9)
+    elseif opt:find("outfile=", 1, true) then
+      outfile = opt:match("[^%c]+", 9)
+    else
+      io.stderr:write("FATAL: unsupported option: " .. opt .. "\n")
+      os.exit(1)
+    end
+  end
+end
+
+
+function args_validate()
+  local args_valid=true
+
+  if listenport == nil or listenport < 1 or listenport > 65535 then
+    args_valid=false
+    io.stderr:write("FATAL: please set a valid 'listenport=...' parameter.\n")
+  end
+
+  if outfile == nil then
+    args_valid=false
+    io.stderr:write("FATAL: please set a valid 'outfile=...' parameter (use `-` for stdout).\n")
+  elseif outfile == "-" then
+    outp = io.stdout
+  else
+    outp, err = io.open(outfile, "w+")
+    if err then
+      args_valid=false
+      io.stderr:write("FATAL: failed to open output stream at '", outfile, "'\n")
+    end
+  end
+
+  if pidfile ~= nil then
+    pidf, err = io.open(pidfile, "w")
+    if err == nil then
+      pidf:write(mypid .. "\n")
+      pidf:close()
+    else
+      args_valid=false
+      io.stderr:write("FATAL: failed to record PID info in  '", pidfile, "'\n")
+    end
+  end
+
+  return args_valid
+end
+
+
+function isoutctime()
+  return os.date("!%Y-%m-%dT%TZ")
+end
+
+
+-- init --
+
+mypid = getpid()
+args_parse()
+
+if not args_validate() then
+  os.exit(1)
+end
+
+udpl:setsockname("*", listenport)
+udpl:settimeout(0.1)
+outp:setvbuf("line")
+io.stderr:write("netconsole-rx.lua / pid " .. mypid .. " / input UDP port " .. listenport .. " / output '" .. outfile .. "'\n")
+
+-- processing loop --
+
+while(true)
+do
+  data, peer, peerport = udpl:receivefrom()
+  if data and string.len(data) > 0 then
+    data, _ = string.gsub(data, "%c", "")
+    if string.byte(data) == 91 then
+      -- simple netconsole message, no ksmg-like metadata
+      outp:write(string.format("%s %s:%s \t%s\n", isoutctime(), peer, peerport, data))
+    else
+      so = string.find(data, ";")
+      if so ~= nil then
+        mdata = string.sub(data, 1, (so - 1))
+        data = string.sub(data, (so + 1))
+        -- TODO: parse mdata, print it sensibly
+        -- <level>,<sequnum>,<timestamp>,<contflag>;<message text>
+        -- outp:write(string.format("%s:%s \t%s\n", peer, peerport, mdata))
+        outp:write(string.format("%s %s:%s \t%s\n", isoutctime(), peer, peerport, data))
+      else
+        io.stderr:write("WARN: garbage input from peer " .. peer .. ":" .. peerport .. " discarded\n")
+      end
+    end
+  end
+end