cpu-info.vala

/* cpu-info.vala
 *
 * requirements:
 *  * lscpu (if not exists, query() always throws an error)
 *
 * deps:
 *  * glib-2.0
 *  * gobject-2.0
 *
 * Written in 2018 by kosmolot ([email protected])
 *
 * To the extent possible under law, the author have dedicated all copyright
 * and related and neighboring rights to this software to the public domain
 * worldwide. This software is distributed without any warranty.
 *
 * You should have received a copy of the CC0 legalcode along with this
 * work. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
 */

public class CpuInfo : Object {
	private static string ARCHITECTURE = "Architecture";
	private static string MODEL_NAME = "Model name";
	private static string SOCKETS = "Socket(s)";
	private static string CORES_PER_SOCKET = "Core(s) per socket";
	private static string THREADS_PER_CORE = "Thread(s) per core";
	private static string MAX_SPEED = "CPU max MHz";

	public static CpuInfo query () throws QueryError {
		string output;
		try {
			Process.spawn_command_line_sync("lscpu", out output);
		} catch (SpawnError err) {
			throw new QueryError.FAILED(@"Failed to spawn process: $(err.message)");
		}

		CpuInfo? result = new CpuInfo();
		result.architecture = extract_value(ARCHITECTURE, output);
		result.model = extract_value(MODEL_NAME, output);
		uint64 socks = uint64.parse( extract_value(SOCKETS, output) );
		uint64 cps = uint64.parse( extract_value(CORES_PER_SOCKET, output) );
		uint64 tpc = uint64.parse( extract_value(THREADS_PER_CORE, output) );
		double speed = double.parse( extract_value(MAX_SPEED, output) );
		result.physical_cores = socks * cps;
		result.logical_cores = result.physical_cores * tpc;
		result.max_speed = speed;
		return result;
	}

	private static string extract_value (string target, string str) throws QueryError {
		Regex regex;
		try {
			string escaped = Regex.escape_string(target);
			regex = new Regex(@"^$escaped:[ \\t]*(.+)[ \\t]*$$", RegexCompileFlags.MULTILINE);
		} catch (RegexError err) {
			throw new QueryError.FAILED(@"Failed to create regex: $(err.message)");
		}
		MatchInfo match;
		bool matched = regex.match(str, 0, out match);
		if (!matched) throw new QueryError.FAILED(@"Failed to fetch info '$target'");
		string? sub_match = match.fetch(1);
		if (sub_match == null) throw new QueryError.FAILED(@"Failed to fetch info '$target'");
		return sub_match;
	}

	public string architecture { get; set; }
	public string model { get; set; }
	public uint64 physical_cores { get; set; }
	public uint64 logical_cores { get; set; }
	public double max_speed { get; set; }

	public void print () {
		GLib.print("> Architecture: %s\n", architecture);
		GLib.print("> CPU model: %s\n", model);
		GLib.print("> Physical cores: %u\n", (uint) physical_cores);
		GLib.print("> Logical cores: %u\n", (uint) logical_cores);
		GLib.print("> Max clock rate: %.2f MHz\n", max_speed);
	}
}

public errordomain QueryError {
	FAILED
}

main.vala

void main () {
	try {
		CpuInfo.query().print();
	} catch (QueryError err) {
		print("Failed to fetch cpu information: %s\n", err.message);
	}
}