Module: LinuxStat::Kernel

Defined in:
lib/linux_stat/kernel.rb

Overview

Shows various Kernel related information of the current system.

Class Method Summary collapse

Class Method Details

.build_date ⇒ Object

Returns the time when the kernel was compiled.

The return value is a Time object.

If the information isn’t available, it will return nil

The time will be searched in specific order.

  • It will match any date matching any of these formats:

  1. %b %d %H:%M:%S %z %Y

  2. %d %b %Y %H:%M:%S %z

  3. %Y-%m-%d

Most kernels have date in them in this format.

Do note that Ruby sometimes fails to work with timezones like BST for example.

In such case, the timezone is unrealiable and often returns the local timezone.

You have to use regexp yourself to get the proper zone.

Use LinuxStat::Kernel.build_date_string to get the original string if you need that.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 88

def build_date
	return nil if splitted.empty?

	@@time ||= begin
		require 'time' unless Time.respond_to?(:strptime)

		splitted.each_cons(5).map do |x|
			joined = x.each(&:strip!).join(?\s.freeze)

			# Match 21 Oct 2020 01:11:20 +0000
			if joined[/^\d{1,2}\s\w{3}\s\d{4}\s\d{1,2}:\d{1,2}:\d{1,2}\s\+\d*$/]
				Time.strptime(joined, '%d %b %Y %H:%M:%S %Z') rescue nil

			# Match Aug 25 17:23:54 UTC 2020
			elsif joined[/^\w{3}\s\d{1,2}\s\d{1,2}:\d{1,2}:\d{2}\s\w+\s\d*$/]
				Time.strptime(joined, '%b %d %H:%M:%S %z %Y') rescue nil

			# Match 2017-09-19
			elsif joined[/\d{4}-\d{1,2}-\d{1,2}/]
				Time.strptime(joined[/\d{4}-\d{2}-\d{2}/] + " +00:00", '%Y-%m-%d %z') rescue nil

			else
				nil
			end
		end.tap(&:compact!)[0]
	end
end

.build_date_string ⇒ Object

Returns the time when the kernel was compiled.

The return value is a String.

If the information isn’t available, it will return nil

The time will be searched in specific order.

  • It will match any date matching any of these formats:

  1. %b %d %H:%M:%S %z %Y

  2. %d %b %Y %H:%M:%S %z

  3. %Y-%m-%d

Most kernels have date in them in this format.

Do note that Ruby sometimes fails to work with timezones like BST for example.

In such case, the timezone is unrealiable and often returns the local timezone.

You have to use regexp yourself to get the proper zone.

Use LinuxStat::Kernel.build_date_string to get the original string if you need that.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 142

def build_date_string
	return nil if splitted.empty?

	@@time2 ||= begin
		require 'time' unless Time.respond_to?(:strptime)

		splitted.each_cons(5).map do |x|
			joined = x.each(&:strip!).join(?\s.freeze)

			# Match 21 Oct 2020 01:11:20 +0000
			if (joined[/^\d{1,2}\s\w{3}\s\d{4}\s\d{1,2}:\d{1,2}:\d{1,2}\s\+\d*$/] && (Time.strptime(joined, '%d %b %Y %H:%M:%S %Z') rescue nil)) ||

			# Match Aug 25 17:23:54 UTC 2020
			(joined[/^\w{3}\s\d{1,2}\s\d{1,2}:\d{1,2}:\d{1,2}\s\w+\s\d*$/] && (Time.strptime(joined, '%b %d %H:%M:%S %z %Y') rescue nil)) ||

			# Match 2017-09-19
			(joined[/\d{4}-\d{1,2}-\d{1,2}/] && (Time.strptime(joined[/\d{4}-\d{2}-\d{2}/] + " +00:00", '%Y-%m-%d %z') rescue nil))
				joined
			else
				nil
			end
		end.tap(&:compact!)[0]
	end
end

.build_user ⇒ Object

Returns the name of the user who built the kernel using KBUILD_FLAGS.

If the information isn’t available, it will return a frozen empty string.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 23

def build_user
	@@build_user ||= string.split(/(\(.+\))/).each(&:strip!)
		.reject(&:empty?).find { |x| x[/^\(.+\)$/] }.to_s
		.split[0].to_s[1..-2].to_s.freeze
end

.compiler ⇒ Object

Returns the compiler used to compile the Linux Kernel.

If the information isn’t available, it will return a frozen empty string.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 35

def compiler
	return ''.freeze if string.empty?

	@@compiler ||= string.split(/(\(.+\))/).each(&:strip!)
		.reject(&:empty?)
		.find { |x| x[/^\(.+\)$/] }.to_s
		.split.find { |x| !x[/^(.+@.+)$/] }.to_s[/\w+/].to_s.freeze

	@@compiler_val ||= case @@compiler
		when /gcc/i then [:gcc ]
		when /clang/i then [:clang]
		when /icc/i then [:icc]
		else [@@compiler &.to_sym]
	end << compiler_version
end

.compiler_version ⇒ Object

Returns the compiler version used to compile the Linux Kernel.

If the information isn’t available, it will return a frozen empty string.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 57

def compiler_version
	@@compiler_version ||= string.split(/(\(.+?\))/).each(&:strip!)
		.reject(&:empty?)[2..4].to_a
		.find { |x| x[/[\d.]+/] }.to_s[/[\d.]+/].to_s.freeze
end

.string ⇒ Object

Reads maximum 1024 bytes from /proc/version and returns the string.

The output is also cached ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 171

def string
	@@string ||= File.readable?('/proc/version') ? IO.read('/proc/version', 1024).tap(&:strip!) : ''
end

.ticks ⇒ Object Also known as: clk_tck

Returns the sc_clk_tck or the same output from command ‘getconf CLK_TCK`.

Also, clk_tck is an alias of this method.

The output is also cached ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 181

def ticks
	@@tick ||= LinuxStat::Sysconf.sc_clk_tck
end

.version ⇒ Object Also known as: release

Returns the Linux Kernel version.

If the information isn’t available, it will return a frozen empty string.

The output is also cached (memoized) ; as changing the value in runtime is unexpected.



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# File 'lib/linux_stat/kernel.rb', line 12

def version
	return ''.freeze if string.empty?
	@@version ||= splitted[2]
end