contrib/statusd/legacy/statusd_sysmon.lua

   1 -- Authors: Vladimir Chizhov <jagoterr@gmail.com>
   2 -- License: Unknown
   3 -- Last Changed: 2005-03-29
   4 --
   5 -- filename :   statusd_sysmon.lua
   6 -- version  :   2.0
   7 -- date     :   2005-03-29
   8 --
   9 -- system monitor for Ion3 WM statusbar
  10 -- Written by Vladimir Chizhov < jagoterr *at* gmail *dot* com >
  11 -- I'll apreciate any comments, bug reports and feature requests :)
  12 --
  13 -- Shows memory, swap and filesystem statistics, based on 'free' and 'df' commands output.
  14 -- Allows lua-expression evaluation with the values.
  15 --
  16 -- This script can work not only as a Ion3 statusd monitor, but also as a standalone script.
  17 -- If it works as a Ion statusd monitor, it reads user settings from statusd.
  18
  19 if not statusd_sysmon then
  20 statusd_sysmon = {
  21     -- UPDATE INTERVAL
  22     --
  23     interval=10*1000,
  24
  25     -- TEMPLATE STRING
  26     --
  27     -- COMMON:
  28     -- %%               - percents symbol (%)
  29     -- ${expression}    - evaluates lua expression
  30     --                    Shortly about expressions:
  31     --                      - may contain all macroses (of format %macros_name or
  32     --                      %{macros_name macros_params*})
  33     --                      - may contain global function calls
  34     --                      - may contain arithmetic, logical operations etc.
  35     --                      - there is a global function 'dpr' defined in this script
  36     --                      for decreasing double numbers' precision (see this
  37     --                      function comments for more information and the example templates)
  38     --
  39     -- RAM:
  40     -- %mem_total       - total available memory
  41     -- %mem_used        - used memory
  42     -- %mem_free        - free memory
  43     -- %mem_buffers     - buffered memory
  44     -- %mem_cached      - cached memory
  45     -- %mem_shared      - shared memory
  46     --
  47     -- SWAP:
  48     -- %swap_total       - total available swap space
  49     -- %swap_used        - used swap space
  50     -- %swap_free        - free swap space
  51     --
  52     -- FS (FileSystem):
  53     -- %{fs_total       mount_point}    - total available space on filesystem
  54     -- %{fs_used        mount_point}    - used space on filesystem
  55     -- %{fs_free        mount_point}    - free space on filesystem
  56     --
  57     -- TEMPLATE EXAMPLES:
  58     --
  59     -- simple swap statistics
  60     -- template = "swap used %swap_used of %swap_total"
  61     --
  62     -- used swap in percents with one sign after comma!
  63     -- how? so... try to understand, I think it's not very hard, if you read the previous comments
  64     -- template = "swap used by ${dpr (%swap_used / %swap_total * 100)}%%"
  65     --
  66     -- RAM used, excluding buffers and cached memory
  67     -- template = "RAM used: ${%mem_used - %mem_buffers - %mem_cached}"
  68     --
  69     -- root filesystem simple info
  70     -- note, that you should specify the actual mount point for filesystem, accordingly to /etc/mtab
  71     -- template = "/ used by %{fs_used /} of %{fs_total /}"
  72     --
  73     -- DEFAULT TEMPLATE:
  74     --
  75     template = "RAM: %mem_used / %mem_total MB (${dpr (%mem_used / %mem_total * 100, 1)} %%) * SWAP: %swap_used / %swap_total MB (${dpr (%swap_used / %swap_total * 100, 1)} %%) * /: %{fs_used /} / %{fs_total /} (${dpr (%{fs_used /} / %{fs_total /} * 100, 1)} %%)",
  76
  77     -- DIMENSION for monitors
  78     --
  79     -- b - bytes
  80     -- k - kilobytes
  81     -- m - megabytes
  82     -- g - gigabytes
  83     --
  84     -- dimension for RAM and SWAP
  85     --
  86     mem_dimension   = "m",
  87     -- dimension for filesystems
  88     --
  89     fs_dimension    = "g",
  90 }
  91 end
  92
  93 local settings
  94 if statusd ~= nil then
  95     settings = table.join (statusd.get_config ("sysmon"), statusd_sysmon)
  96 else
  97     settings = statusd_sysmon
  98 end
  99
 100 local factors = {
 101     b = 1,
 102     k = 1024,
 103     m = 1024^2,
 104     g = 1024^3,
 105 }
 106
 107 local metrics = {}
 108
 109 -- --------------------------------------------------------------------------
 110 -- Decreases the precision of the floating number
 111 -- @param number    the number to decrease it's precision
 112 -- @param signs_q   the quantity of signs after the comma to be left
 113 function dpr (number, signs_q)
 114     local pattern = "%d+"
 115     if signs_q == nil then
 116         signs_q = 2
 117     end
 118     if signs_q ~= 0 then
 119         pattern = pattern.."%."
 120     end
 121     for i = 1, tonumber (signs_q)  do
 122         pattern = pattern.."%d"
 123     end
 124     return string.gsub (number, "("..pattern..")(.*)", "%1")
 125 end
 126
 127 -- --------------------------------------------------------------------------
 128 -- Retrieves information from 'free' command output
 129 local function parse_free_command ()
 130     local f = io.popen ('free -'..settings.mem_dimension, 'r')
 131     local s = f:read('*a')
 132     f:close()
 133     local st, en
 134
 135     st, en,
 136     metrics.mem_total,
 137     metrics.mem_used,
 138     metrics.mem_free,
 139     metrics.mem_shared,
 140     metrics.mem_buffers,
 141     metrics.mem_cached
 142         = string.find(s, 'Mem:%s*(%d+)%s+(%d+)%s+(%d+)%s+(%d+)%s+(%d+)%s+(%d+)')
 143     st, en,
 144     metrics.swap_total,
 145     metrics.swap_used,
 146     metrics.swap_free
 147         = string.find(s, 'Swap:%s*(%d+)%s+(%d+)%s+(%d+)')
 148 end
 149
 150 -- --------------------------------------------------------------------------
 151 -- Retrieves information from 'df' command output
 152 local function parse_df_command ()
 153     local factor = factors[settings.fs_dimension]
 154     local f = io.popen ('df --block-size=1 -P', 'r')
 155     -- local s = f:read ("*l")
 156     for line in f:lines () do
 157         local st, en, fs, total, used, free, mount_point =
 158             string.find (line, '(%S+)%s+(%d+)%s+(%d+)%s+(%d+)%s+[%-%d]-%%?%s+(.*)')
 159         if fs ~= nil then
 160             metrics["fs_total->"..mount_point] = string.gsub (total / factor, '(%d+%.%d%d)(.*)', "%1")
 161             metrics["fs_used->"..mount_point] = string.gsub (used / factor, '(%d+%.%d%d)(.*)', "%1")
 162             metrics["fs_free->"..mount_point] = string.gsub (free / factor, '(%d+%.%d%d)(.*)', "%1")
 163         end
 164     end
 165     f:close ()
 166
 167 end
 168
 169 local sysmon_timer
 170
 171 -- --------------------------------------------------------------------------
 172 -- Main calculating of values, template parsing and Ion statusd updating
 173 local function update_sysmon ()
 174     local sysmon_st = settings.template
 175
 176     parse_free_command ()
 177
 178     parse_df_command ()
 179
 180     -- filling the template by actual values
 181     sysmon_st = string.gsub (sysmon_st, "%%%{([%w%_]+)%s+(%S-)%}", function (arg1, arg2)
 182         return(metrics[arg1.."->"..arg2] or "")
 183     end)
 184     sysmon_st = string.gsub (sysmon_st, "%%([%w%_]+)", function (arg1)
 185         return (metrics[arg1] or "")
 186     end)
 187     sysmon_st = string.gsub (sysmon_st, "%$%{(.-)%}", function (arg1)
 188         return loadstring("return "..arg1)()
 189     end)
 190     -- replacing the '%%' macros with the '%' symbol
 191     sysmon_st = string.gsub (sysmon_st, "%%%%", "%%")
 192
 193     if statusd ~= nil then
 194         statusd.inform ("sysmon_template", sysmon_st)
 195         statusd.inform ("sysmon", sysmon_st)
 196         sysmon_timer:set (settings.interval, update_sysmon)
 197     else
 198         io.stdout:write (sysmon_st.."\n")
 199     end
 200 end
 201
 202 -- --------------------------------------------------------------------------
 203 -- Init
 204 if statusd ~= nil then
 205     sysmon_timer = statusd.create_timer ()
 206 end
 207 update_sysmon ()
 208