lain/helpers.lua

186 lines
4.0 KiB
Lua

--[[
Licensed under GNU General Public License v2
* (c) 2013, Luke Bonham
--]]
local debug = require("debug")
local assert = assert
local capi = { timer = require("gears.timer") }
local io = { open = io.open,
lines = io.lines,
popen = io.popen }
local rawget = rawget
local table = { sort = table.sort }
local wibox = require("wibox")
-- Lain helper functions for internal use
-- lain.helpers
local helpers = {}
helpers.lain_dir = debug.getinfo(1, 'S').source:match[[^@(.*/).*$]]
helpers.icons_dir = helpers.lain_dir .. 'icons/'
helpers.scripts_dir = helpers.lain_dir .. 'scripts/'
-- {{{ Modules loader
function helpers.wrequire(table, key)
local module = rawget(table, key)
return module or require(table._NAME .. '.' .. key)
end
-- }}}
-- {{{ File operations
-- see if the file exists and is readable
function helpers.file_exists(file)
local f = io.open(file)
if f then
local s = f:read()
f:close()
f = s
end
return f ~= nil
end
-- get all lines from a file, returns an empty
-- list/table if the file does not exist
function helpers.lines_from(file)
if not helpers.file_exists(file) then return {} end
local lines = {}
for line in io.lines(file) do
lines[#lines + 1] = line
end
return lines
end
-- match all lines from a file, returns an empty
-- list/table if the file or match does not exist
function helpers.lines_match(regexp, file)
local lines = {}
for index,line in pairs(helpers.lines_from(file)) do
if string.match(line, regexp) then
lines[index] = line
end
end
return lines
end
-- get first line of a file, return nil if
-- the file does not exist
function helpers.first_line(file)
return helpers.lines_from(file)[1]
end
-- get first non empty line from a file,
-- returns nil otherwise
function helpers.first_nonempty_line(file)
for k,v in pairs(helpers.lines_from(file)) do
if #v then return v end
end
return nil
end
-- }}}
-- {{{ Timer maker
helpers.timer_table = {}
function helpers.newtimer(_name, timeout, fun, nostart)
local name = timeout
if not helpers.timer_table[name] then
helpers.timer_table[name] = capi.timer({ timeout = timeout })
helpers.timer_table[name]:start()
end
helpers.timer_table[name]:connect_signal("timeout", fun)
if not nostart then
helpers.timer_table[name]:emit_signal("timeout")
end
end
-- }}}
-- {{{ Pipe operations
-- read the full output of a command output
function helpers.read_pipe(cmd)
local f = assert(io.popen(cmd))
local output = f:read("*all")
f:close()
return output
end
-- return line iterator of a command output
function helpers.pipelines(...)
local f = assert(io.popen(...))
return function () -- iterator
local data = f:read()
if data == nil then f:close() end
return data
end
end
-- }}}
-- {{{ A map utility
helpers.map_table = {}
function helpers.set_map(element, value)
helpers.map_table[element] = value
end
function helpers.get_map(element)
return helpers.map_table[element]
end
-- }}}
-- {{{ Misc
-- check if an element exist on a table
function helpers.element_in_table(element, tbl)
for _, i in pairs(tbl) do
if i == element then
return true
end
end
return false
end
-- iterate over table of records sorted by keys
function helpers.spairs(t)
-- collect the keys
local keys = {}
for k in pairs(t) do keys[#keys+1] = k end
table.sort(keys)
-- return the iterator function
local i = 0
return function()
i = i + 1
if keys[i] then
return keys[i], t[keys[i]]
end
end
end
-- create a lain textbox widget
function helpers.make_widget_textbox()
local w = wibox.widget.textbox('')
local t = wibox.widget.base.make_widget(w)
t.widget = w
return t
end
-- }}}
return helpers