--[[
Licensed under GNU General Public License v2
+ * (c) 2015, worron
* (c) 2013, Alexander Yakushev
--]]
-- Asynchronous io.popen for Awesome WM.
--- How to use...
--- ...asynchronously:
--- asyncshell.request('wscript -Kiev', function(f) wwidget.text = f:read("*l") end)
--- ...synchronously
--- wwidget.text = asyncshell.demand('wscript -Kiev', 5):read("*l") or "Error"
+-- How to use:
+-- asyncshell.request('wscript -Kiev', function(output) wwidget.text = output end)
-local spawn = require('awful.util').spawn
+-- Grab environment
+local awful = require('awful')
-asyncshell = {}
-asyncshell.request_table = {}
-asyncshell.id_counter = 0
-asyncshell.folder = "/tmp/asyncshell"
-asyncshell.file_template = asyncshell.folder .. '/req'
+-- Avoid discrepancies across multiple shells
+awful.util.shell = '/bin/sh'
--- Create a directory for asynchell response files
-os.execute("mkdir -p " .. asyncshell.folder)
+-- Initialize tables for module
+asyncshell = { request_table = {}, id_counter = 0 }
--- Returns next tag - unique identifier of the request
+-- Request counter
local function next_id()
- asyncshell.id_counter = (asyncshell.id_counter + 1) % 100000
- return asyncshell.id_counter
+ asyncshell.id_counter = (asyncshell.id_counter + 1) % 10000
+ return asyncshell.id_counter
end
--- Sends an asynchronous request for an output of the shell command.
+-- Remove given request
+function asyncshell.clear(id)
+ if asyncshell.request_table[id] then
+ if asyncshell.request_table[id].timer then
+ asyncshell.request_table[id].timer:stop()
+ asyncshell.request_table[id].timer = nil
+ end
+ asyncshell.request_table[id] = nil
+ end
+end
+
+-- Sends an asynchronous request for an output of the shell command
-- @param command Command to be executed and taken output from
-- @param callback Function to be called when the command finishes
--- @return Request ID
-function asyncshell.request(command, callback)
- local id = next_id()
- local tmpfname = asyncshell.file_template .. id
- asyncshell.request_table[id] = {callback = callback}
- local req =
- string.format("bash -c '%s > %s; " ..
- 'echo "asyncshell.deliver(%s)" | ' ..
- "awesome-client' 2> /dev/null",
- string.gsub(command, "'", "'\\''"), tmpfname,
- id, tmpfname)
- spawn(req, false)
- return id
-end
+-- @param timeout Maximum amount of time to wait for the result (optional)
+function asyncshell.request(command, callback, timeout)
+ local id = next_id()
+ asyncshell.request_table[id] = { callback = callback }
--- Calls the remembered callback function on the output of the shell
--- command.
--- @param id Request ID
--- @param output The output file of the shell command to be delievered
-function asyncshell.deliver(id)
- if asyncshell.request_table[id] and
- asyncshell.request_table[id].callback then
- local output = io.open(asyncshell.file_template .. id, 'r')
- asyncshell.request_table[id].callback(output)
- end
+ local formatted_command = string.gsub(command, '"','\"')
+
+ local req = string.format(
+ "echo \"asyncshell.deliver(%s, [[\\\"$(%s)\\\"]])\" | awesome-client &",
+ id, formatted_command
+ )
+
+ if type(awful.spawn) == 'table' then
+ awful.spawn.with_shell(req)
+ else
+ awful.util.spawn_with_shell(req)
+ end
+
+ if timeout then
+ asyncshell.request_table[id].timer = timer({ timeout = timeout })
+ asyncshell.request_table[id].timer:connect_signal("timeout", function() asyncshell.clear(id) end)
+ asyncshell.request_table[id].timer:start()
+ end
end
--- Sends a synchronous request for an output of the command. Waits for
--- the output, but if the given timeout expires returns nil.
--- @param command Command to be executed and taken output from
--- @param timeout Maximum amount of time to wait for the result
--- @return File handler on success, nil otherwise
-function asyncshell.demand(command, timeout)
- local id = next_id()
- local tmpfname = asyncshell.file_template .. id
- local f = io.popen(string.format("(%s > %s; echo asyncshell_done) & " ..
- "(sleep %s; echo asynchell_timeout)",
- command, tmpfname, timeout))
- local result = f:read("*line")
- if result == "asyncshell_done" then
- return io.open(tmpfname)
- end
+-- Calls the remembered callback function on the output of the shell command
+-- @param id Request ID
+-- @param output Shell command output to be delievered
+function asyncshell.deliver(id, output)
+ local output = string.sub(output, 2, -2)
+ if asyncshell.request_table[id] then
+ asyncshell.request_table[id].callback(output)
+ asyncshell.clear(id)
+ end
end
return asyncshell