%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2018. All Rights Reserved.
%%
%% 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
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
-module(disksup).
-behaviour(gen_server).
%% API
-export([start_link/0]).
-export([get_disk_data/0,
get_check_interval/0, set_check_interval/1,
get_almost_full_threshold/0, set_almost_full_threshold/1]).
-export([dummy_reply/1, param_type/2, param_default/1]).
%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
terminate/2, code_change/3]).
%% Other exports
-export([format_status/2, parse_df/2]).
-record(state, {threshold, timeout, os, diskdata = [],port}).
%%----------------------------------------------------------------------
%% API
%%----------------------------------------------------------------------
start_link() ->
gen_server:start_link({local, disksup}, disksup, [], []).
get_disk_data() ->
os_mon:call(disksup, get_disk_data, infinity).
get_check_interval() ->
os_mon:call(disksup, get_check_interval, infinity).
set_check_interval(Minutes) ->
case param_type(disk_space_check_interval, Minutes) of
true ->
os_mon:call(disksup, {set_check_interval, Minutes}, infinity);
false ->
erlang:error(badarg)
end.
get_almost_full_threshold() ->
os_mon:call(disksup, get_almost_full_threshold, infinity).
set_almost_full_threshold(Float) ->
case param_type(disk_almost_full_threshold, Float) of
true ->
os_mon:call(disksup, {set_almost_full_threshold, Float}, infinity);
false ->
erlang:error(badarg)
end.
dummy_reply(get_disk_data) ->
[{"none", 0, 0}];
dummy_reply(get_check_interval) ->
minutes_to_ms(os_mon:get_env(disksup, disk_space_check_interval));
dummy_reply({set_check_interval, _}) ->
ok;
dummy_reply(get_almost_full_threshold) ->
round(os_mon:get_env(disksup, disk_almost_full_threshold) * 100);
dummy_reply({set_almost_full_threshold, _}) ->
ok.
param_type(disk_space_check_interval, Val) when is_integer(Val),
Val>=1 -> true;
param_type(disk_almost_full_threshold, Val) when is_number(Val),
0=<Val,
Val=<1 -> true;
param_type(disksup_posix_only, Val) when Val==true; Val==false -> true;
param_type(_Param, _Val) -> false.
param_default(disk_space_check_interval) -> 30;
param_default(disk_almost_full_threshold) -> 0.80;
param_default(disksup_posix_only) -> false.
%%----------------------------------------------------------------------
%% gen_server callbacks
%%----------------------------------------------------------------------
init([]) ->
process_flag(trap_exit, true),
process_flag(priority, low),
PosixOnly = os_mon:get_env(disksup, disksup_posix_only),
OS = get_os(PosixOnly),
Port = case OS of
{unix, Flavor} when Flavor==sunos4;
Flavor==solaris;
Flavor==freebsd;
Flavor==dragonfly;
Flavor==darwin;
Flavor==linux;
Flavor==posix;
Flavor==openbsd;
Flavor==netbsd;
Flavor==irix64;
Flavor==irix ->
start_portprogram();
{win32, _OSname} ->
not_used;
_ ->
exit({unsupported_os, OS})
end,
%% Read the values of some configuration parameters
Threshold = os_mon:get_env(disksup, disk_almost_full_threshold),
Timeout = os_mon:get_env(disksup, disk_space_check_interval),
%% Initiation first disk check
self() ! timeout,
{ok, #state{port=Port, os=OS,
threshold=round(Threshold*100),
timeout=minutes_to_ms(Timeout)}}.
handle_call(get_disk_data, _From, State) ->
{reply, State#state.diskdata, State};
handle_call(get_check_interval, _From, State) ->
{reply, State#state.timeout, State};
handle_call({set_check_interval, Minutes}, _From, State) ->
Timeout = minutes_to_ms(Minutes),
{reply, ok, State#state{timeout=Timeout}};
handle_call(get_almost_full_threshold, _From, State) ->
{reply, State#state.threshold, State};
handle_call({set_almost_full_threshold, Float}, _From, State) ->
Threshold = round(Float * 100),
{reply, ok, State#state{threshold=Threshold}};
handle_call({set_threshold, Threshold}, _From, State) -> % test only
{reply, ok, State#state{threshold=Threshold}}.
handle_cast(_Msg, State) ->
{noreply, State}.
handle_info(timeout, State) ->
NewDiskData = check_disk_space(State#state.os, State#state.port,
State#state.threshold),
{ok, _Tref} = timer:send_after(State#state.timeout, timeout),
{noreply, State#state{diskdata = NewDiskData}};
handle_info({'EXIT', _Port, Reason}, State) ->
{stop, {port_died, Reason}, State#state{port=not_used}};
handle_info(_Info, State) ->
{noreply, State}.
terminate(_Reason, State) ->
clear_alarms(),
case State#state.port of
not_used ->
ok;
Port ->
port_close(Port)
end,
ok.
%% os_mon-2.0.1
%% For live downgrade to/upgrade from os_mon-1.8[.1]
code_change(Vsn, PrevState, "1.8") ->
case Vsn of
%% Downgrade from this version
{down, _Vsn} ->
State = case PrevState#state.port of
not_used -> PrevState#state{port=noport};
_ -> PrevState
end,
{ok, State};
%% Upgrade to this version
_Vsn ->
State = case PrevState#state.port of
noport -> PrevState#state{port=not_used};
_ -> PrevState
end,
{ok, State}
end;
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%----------------------------------------------------------------------
%% Other exports
%%----------------------------------------------------------------------
format_status(_Opt, [_PDict, #state{os = OS, threshold = Threshold,
timeout = Timeout,
diskdata = DiskData}]) ->
[{data, [{"OS", OS},
{"Timeout", Timeout},
{"Threshold", Threshold},
{"DiskData", DiskData}]}].
%%----------------------------------------------------------------------
%% Internal functions
%%----------------------------------------------------------------------
get_os(PosixOnly) ->
case os:type() of
{unix, sunos} ->
case os:version() of
{5,_,_} -> {unix, solaris};
{4,_,_} -> {unix, sunos4};
V -> exit({unknown_os_version, V})
end;
{unix, _} when PosixOnly ->
{unix, posix};
{unix, irix64} -> {unix, irix};
OS ->
OS
end.
%%--Port handling functions---------------------------------------------
start_portprogram() ->
open_port({spawn, "sh -s disksup 2>&1"}, [stream]).
my_cmd(Cmd0, Port) ->
%% Insert a new line after the command, in case the command
%% contains a comment character
Cmd = io_lib:format("(~s\n) </dev/null; echo \"\^M\"\n", [Cmd0]),
Port ! {self(), {command, [Cmd, 10]}},
get_reply(Port, []).
get_reply(Port, O) ->
receive
{Port, {data, N}} ->
case newline(N, O) of
{ok, Str} -> Str;
{more, Acc} -> get_reply(Port, Acc)
end;
{'EXIT', Port, Reason} ->
exit({port_died, Reason})
end.
newline([13|_], B) -> {ok, lists:reverse(B)};
newline([H|T], B) -> newline(T, [H|B]);
newline([], B) -> {more, B}.
%%--Check disk space----------------------------------------------------
check_disk_space({win32,_}, not_used, Threshold) ->
Result = os_mon_sysinfo:get_disk_info(),
check_disks_win32(Result, Threshold);
check_disk_space({unix, solaris}, Port, Threshold) ->
Result = my_cmd("/usr/bin/df -lk", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, irix}, Port, Threshold) ->
Result = my_cmd("/usr/sbin/df -lk",Port),
check_disks_irix(skip_to_eol(Result), Threshold);
check_disk_space({unix, linux}, Port, Threshold) ->
Result = my_cmd("/bin/df -lk -x squashfs", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, posix}, Port, Threshold) ->
Result = my_cmd("df -k -P", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, dragonfly}, Port, Threshold) ->
Result = my_cmd("/bin/df -k -t ufs,hammer", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, freebsd}, Port, Threshold) ->
Result = my_cmd("/bin/df -k -l", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, openbsd}, Port, Threshold) ->
Result = my_cmd("/bin/df -k -l", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, netbsd}, Port, Threshold) ->
Result = my_cmd("/bin/df -k -t ffs", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, sunos4}, Port, Threshold) ->
Result = my_cmd("df", Port),
check_disks_solaris(skip_to_eol(Result), Threshold);
check_disk_space({unix, darwin}, Port, Threshold) ->
Result = my_cmd("/bin/df -i -k -t ufs,hfs,apfs", Port),
check_disks_susv3(skip_to_eol(Result), Threshold).
% This code works for Linux and FreeBSD as well
check_disks_solaris("", _Threshold) ->
[];
check_disks_solaris("\n", _Threshold) ->
[];
check_disks_solaris(Str, Threshold) ->
case parse_df(Str, posix) of
{ok, {KB, Cap, MntOn}, RestStr} ->
if
Cap >= Threshold ->
set_alarm({disk_almost_full, MntOn}, []);
true ->
clear_alarm({disk_almost_full, MntOn})
end,
[{MntOn, KB, Cap} |
check_disks_solaris(RestStr, Threshold)];
_Other ->
check_disks_solaris(skip_to_eol(Str),Threshold)
end.
%% @private
%% @doc Predicate to take a word from the input string until a space or
%% a percent '%' sign (the Capacity field is followed by a %)
parse_df_is_not_space($ ) -> false;
parse_df_is_not_space($%) -> false;
parse_df_is_not_space(_) -> true.
%% @private
%% @doc Predicate to take spaces away from string. Stops on a non-space
parse_df_is_space($ ) -> true;
parse_df_is_space(_) -> false.
%% @private
%% @doc Predicate to consume remaining characters until end of line.
parse_df_is_not_eol($\r) -> false;
parse_df_is_not_eol($\n) -> false;
parse_df_is_not_eol(_) -> true.
%% @private
%% @doc Trims leading non-spaces (the word) from the string then trims spaces.
parse_df_skip_word(Input) ->
Remaining = lists:dropwhile(fun parse_df_is_not_space/1, Input),
lists:dropwhile(fun parse_df_is_space/1, Remaining).
%% @private
%% @doc Takes all non-spaces and then drops following spaces.
parse_df_take_word(Input) ->
{Word, Remaining0} = lists:splitwith(fun parse_df_is_not_space/1, Input),
Remaining1 = lists:dropwhile(fun parse_df_is_space/1, Remaining0),
{Word, Remaining1}.
%% @private
%% @doc Takes all non-spaces and then drops the % after it and the spaces.
parse_df_take_word_percent(Input) ->
{Word, Remaining0} = lists:splitwith(fun parse_df_is_not_space/1, Input),
%% Drop the leading % or do nothing
Remaining1 = case Remaining0 of
[$% | R1] -> R1;
_ -> Remaining0 % Might be no % or empty list even
end,
Remaining2 = lists:dropwhile(fun parse_df_is_space/1, Remaining1),
{Word, Remaining2}.
%% @private
%% @doc Given a line of 'df' POSIX/SUSv3 output split it into fields:
%% a string (mounted device), 4 integers (kilobytes, used, available
%% and capacity), skip % sign, (optionally for susv3 can also skip IUsed, IFree
%% and ICap% fields) then take remaining characters as the mount path
-spec parse_df(string(), posix | susv3) ->
{error, parse_df} | {ok, {integer(), integer(), list()}, string()}.
parse_df(Input0, Flavor) ->
%% Format of Posix/Linux df output looks like Header + Lines
%% Filesystem 1024-blocks Used Available Capacity Mounted on
%% udev 2467108 0 2467108 0% /dev
Input1 = parse_df_skip_word(Input0), % skip device path field
{KbStr, Input2} = parse_df_take_word(Input1), % take Kb field
Input3 = parse_df_skip_word(Input2), % skip Used field
Input4 = parse_df_skip_word(Input3), % skip Avail field
% take Capacity% field; drop a % sign following the capacity
{CapacityStr, Input5} = parse_df_take_word_percent(Input4),
%% Format of OS X/SUSv3 df looks similar to POSIX but has 3 extra columns
%% Filesystem 1024-blocks Used Available Capacity iused ifree %iused Mounted
%% /dev/disk1 243949060 2380 86690680 65% 2029724 37555 0% /
Input6 = case Flavor of
posix -> Input5;
susv3 -> % there are 3 extra integers we want to skip
Input5a = parse_df_skip_word(Input5), % skip IUsed field
Input5b = parse_df_skip_word(Input5a), % skip IFree field
%% skip the value of ICap + '%' field
{_, Input5c} = parse_df_take_word_percent(Input5b),
Input5c
end,
% path is the remaining string till end of line
{MountPath, Input7} = lists:splitwith(fun parse_df_is_not_eol/1, Input6),
% Trim the newlines
Remaining = lists:dropwhile(fun(X) -> not parse_df_is_not_eol(X) end,
Input7),
try
Kb = erlang:list_to_integer(KbStr),
Capacity = erlang:list_to_integer(CapacityStr),
{ok, {Kb, Capacity, MountPath}, Remaining}
catch error:badarg ->
{error, parse_df}
end.
% Parse per SUSv3 specification, notably recent OS X
check_disks_susv3("", _Threshold) ->
[];
check_disks_susv3("\n", _Threshold) ->
[];
check_disks_susv3(Str, Threshold) ->
case parse_df(Str, susv3) of
{ok, {KB, Cap, MntOn}, RestStr} ->
if
Cap >= Threshold ->
set_alarm({disk_almost_full, MntOn}, []);
true ->
clear_alarm({disk_almost_full, MntOn})
end,
[{MntOn, KB, Cap} |
check_disks_susv3(RestStr, Threshold)];
_Other ->
check_disks_susv3(skip_to_eol(Str),Threshold)
end.
%% Irix: like Linux with an extra FS type column and no '%'.
check_disks_irix("", _Threshold) -> [];
check_disks_irix("\n", _Threshold) -> [];
check_disks_irix(Str, Threshold) ->
case io_lib:fread("~s~s~d~d~d~d~s", Str) of
{ok, [_FS, _FSType, KB, _Used, _Avail, Cap, MntOn], RestStr} ->
if Cap >= Threshold -> set_alarm({disk_almost_full, MntOn}, []);
true -> clear_alarm({disk_almost_full, MntOn}) end,
[{MntOn, KB, Cap} | check_disks_irix(RestStr, Threshold)];
_Other ->
check_disks_irix(skip_to_eol(Str),Threshold)
end.
check_disks_win32([], _Threshold) ->
[];
check_disks_win32([H|T], Threshold) ->
case io_lib:fread("~s~s~d~d~d", H) of
{ok, [Drive,"DRIVE_FIXED",BAvail,BTot,_TotFree], _RestStr} ->
Cap = trunc((BTot-BAvail) / BTot * 100),
if
Cap >= Threshold ->
set_alarm({disk_almost_full, Drive}, []);
true ->
clear_alarm({disk_almost_full, Drive})
end,
[{Drive, BTot div 1024, Cap} |
check_disks_win32(T, Threshold)]; % Return Total Capacity in Kbytes
{ok,_,_RestStr} ->
check_disks_win32(T,Threshold);
_Other ->
[]
end.
%%--Alarm handling------------------------------------------------------
set_alarm(AlarmId, AlarmDescr) ->
case get(AlarmId) of
set ->
ok;
undefined ->
alarm_handler:set_alarm({AlarmId, AlarmDescr}),
put(AlarmId, set)
end.
clear_alarm(AlarmId) ->
case get(AlarmId) of
set ->
alarm_handler:clear_alarm(AlarmId),
erase(AlarmId);
undefined ->
ok
end.
clear_alarms() ->
lists:foreach(fun({{disk_almost_full, _MntOn} = AlarmId, set}) ->
alarm_handler:clear_alarm(AlarmId);
(_Other) ->
ignore
end,
get()).
%%--Auxiliary-----------------------------------------------------------
%% Type conversion
minutes_to_ms(Minutes) ->
trunc(60000*Minutes).
skip_to_eol([]) ->
[];
skip_to_eol([$\n | T]) ->
T;
skip_to_eol([_ | T]) ->
skip_to_eol(T).
