Method: LinuxStat::Battery.devices_stat

Defined in:

lib/linux_stat/battery.rb

.devices_stat ⇒ Object

A linux system can have multiple batteries. This method attempts to find all of them and return a Hash based on the availibility of the information.

This method is somewhat slower than other Battery module singleton methods. Because it does various checks and opens various files from /sys/

For example, a sample output can be like this (taken on a test system):

LinuxStat::Battery.devices_stat
=> {:AC=>{:type=>"Mains", :online=>1},

:BAT0=>CYMGM77”, :manufacturer=>“Samsung SDI”, :type=>“Battery”, :status=>“Full”, :capacity=>100, :voltage_min_design=>11.4, :charge_full_design=>3.684, :charge_full_design_wh=>42.0, :voltage_now=>12.558, :charge_now=>2.087, :charge_now_wh=>26.21, :charge_full_wh=>23.79, :charge_percentage=>100.0, :hidpp_battery_0=>Keyboard”, :manufacturer=>“Logitech”, :type=>“Battery”, :status=>“Discharging”, :online=>1}

If you need info about lots of batteries, use this method. If the informations are not available, it will return empty Hash for each devices. If the system has no batteries, it will return an empty Hash.

# File 'lib/linux_stat/battery.rb', line 201

def devices_stat
	h = {}
	Dir["/sys/class/power_supply/*/".freeze].tap(&:sort!).each do |x|
		# model name
		mn_file = File.join(x, 'model_name'.freeze).freeze
		model_name = File.readable?(mn_file) ? IO.read(mn_file).strip : nil

		# manufacturer
		m_f = File.join(x, 'manufacturer'.freeze).freeze
		manufacturer = File.readable?(m_f) ? IO.read(m_f).strip : nil

		# type
		t_f = File.join(x, 'type'.freeze).freeze
		type = File.readable?(t_f) ? IO.read(t_f).strip : nil

		# capacity
		c_file = File.join(x, 'capacity'.freeze).freeze
		capacity = File.readable?(c_file) ? IO.read(c_file).to_i : nil

		# voltage now
		vn_f = File.join(x, 'voltage_now'.freeze).freeze
		voltage_now = File.readable?(vn_f) ? IO.read(vn_f).to_i.fdiv(1_000_000) : nil

		# charge now
		cn_f = File.join(x, 'charge_now'.freeze).freeze
		charge_now = if File.readable?(cn_f)
			IO.read(cn_f).to_i.fdiv(1_000_000)
		else
			en_f = File.join(x, 'energy_now'.freeze)
			if File.readable?(en_f)
				IO.read(en_f) .to_i.fdiv(1_000_000)
			else
				nil
			end
		end

		# voltage min design
		vmd_f = File.join(x, 'voltage_min_design'.freeze).freeze
		v_m_d = File.readable?(vmd_f) ? IO.read(vmd_f).to_i.fdiv(1_000_000) : nil

		# charge full design
		cfd_f = File.join(x, 'charge_full_design'.freeze).freeze
		c_f_d = File.readable?(cfd_f) ? IO.read(cfd_f).to_i.fdiv(1_000_000) : nil

		# charge full
		cf_f = File.join(x, 'charge_full'.freeze).freeze
		charge_full = if File.readable?(cf_f)
			IO.read(cf_f).to_i.fdiv(1_000_000)
		else
			ef_f = File.join(x, 'energy_full'.freeze)
			if File.readable?(ef_f)
				IO.read(ef_f).to_i.fdiv(1_000_000)
			else
				nil
			end
		end

		# status
		s_f = File.join(x, 'status'.freeze).freeze
		status = File.readable?(s_f) ? IO.read(s_f).strip : nil

		# online
		o_f = File.join(x, 'online'.freeze).freeze
		online = File.readable?(o_f) ? IO.read(o_f).to_i : nil

		charge_percentage = if charge_now && charge_full
			charge_now.*(100).fdiv(charge_full).round(2)
		else
			nil
		end

		# full_charge_design (WH)
		c_f_d_wh =  if c_f_d && v_m_d
			v_m_d.*(c_f_d).round(2)
		else
			nil
		end

		c_n_wh = if voltage_now && charge_now
			voltage_now.*(charge_now).round(2)
		else
			nil
		end

		c_f_wh = if v_m_d && charge_full
			v_m_d.*(charge_full).round(2)
		else
			nil
		end

		ret = {}
		ret[:model] = model_name if model_name
		ret[:manufacturer] = manufacturer if manufacturer
		ret[:type] = type if type

		ret[:status] = status if status
		ret[:online] = online if online
		ret[:capacity] = capacity if capacity

		ret[:voltage_min_design] = v_m_d if v_m_d
		ret[:charge_full_design] = c_f_d if c_f_d
		ret[:charge_full_design_wh] = c_f_d_wh if c_f_d_wh

		ret[:voltage_now] = voltage_now if voltage_now
		ret[:charge_now] = charge_now if charge_now

		ret[:charge_now_wh] = c_n_wh if c_n_wh
		ret[:charge_full_wh] = c_f_wh if c_f_wh
		ret[:charge_percentage] = charge_percentage if charge_percentage

		h.merge!(File.split(x)[-1].to_sym => ret)
	end
	h
end