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ndg/src/nd.zig

273 lines
8.8 KiB
Zig

const buildopts = @import("build_options");
const std = @import("std");
const os = std.os;
const sys = os.system;
const time = std.time;
const Address = std.net.Address;
const nif = @import("nif");
const comm = @import("comm.zig");
const Daemon = @import("nd/Daemon.zig");
const screen = @import("ui/screen.zig");
const logger = std.log.scoped(.nd);
const stderr = std.io.getStdErr().writer();
/// prints usage help text to stderr.
fn usage(prog: []const u8) !void {
try stderr.print(
\\usage: {s} -gui path/to/ngui -gui-user username -wpa path
\\
\\nd is a short for nakamochi daemon.
\\the daemon executes ngui as a child process and runs until
\\TERM or INT signal is received.
\\
\\nd logs messages to stderr.
\\
, .{prog});
}
/// prints messages in the same way std.fmt.format does and exits the process
/// with a non-zero code.
fn fatal(comptime fmt: []const u8, args: anytype) noreturn {
stderr.print(fmt, args) catch {};
if (fmt[fmt.len - 1] != '\n') {
stderr.writeByte('\n') catch {};
}
std.process.exit(1);
}
/// nd program args. see usage.
const NdArgs = struct {
gui: ?[:0]const u8 = null, // = "ngui",
gui_user: ?[:0]const u8 = null, // u8 = "uiuser",
wpa: ?[:0]const u8 = null, // = "/var/run/wpa_supplicant/wlan0",
fn deinit(self: @This(), allocator: std.mem.Allocator) void {
if (self.gui) |p| allocator.free(p);
if (self.gui_user) |p| allocator.free(p);
if (self.wpa) |p| allocator.free(p);
}
};
/// parses and validates program args.
fn parseArgs(gpa: std.mem.Allocator) !NdArgs {
var flags: NdArgs = .{};
var args = try std.process.ArgIterator.initWithAllocator(gpa);
defer args.deinit();
const prog = args.next() orelse return error.NoProgName;
var lastarg: enum {
none,
gui,
gui_user,
wpa,
} = .none;
while (args.next()) |a| {
switch (lastarg) {
.gui => {
flags.gui = try gpa.dupeZ(u8, a);
lastarg = .none;
continue;
},
.gui_user => {
flags.gui_user = try gpa.dupeZ(u8, a);
lastarg = .none;
continue;
},
.wpa => {
flags.wpa = try gpa.dupeZ(u8, a);
lastarg = .none;
continue;
},
.none => {},
}
if (std.mem.eql(u8, a, "-h") or std.mem.eql(u8, a, "-help") or std.mem.eql(u8, a, "--help")) {
usage(prog) catch {};
std.process.exit(1);
} else if (std.mem.eql(u8, a, "-v")) {
try stderr.print("{any}\n", .{buildopts.semver});
std.process.exit(0);
} else if (std.mem.eql(u8, a, "-gui")) {
lastarg = .gui;
} else if (std.mem.eql(u8, a, "-gui-user")) {
lastarg = .gui_user;
} else if (std.mem.eql(u8, a, "-wpa")) {
lastarg = .wpa;
} else {
fatal("unknown arg name {s}", .{a});
}
}
if (lastarg != .none) {
fatal("invalid arg: {s} requires a value", .{@tagName(lastarg)});
}
if (flags.gui == null) fatal("missing -gui arg", .{});
if (flags.gui_user == null) fatal("missing -gui-user arg", .{});
if (flags.wpa == null) fatal("missing -wpa arg", .{});
return flags;
}
/// quit signals nd to exit.
/// TODO: thread-safety?
var quit = false;
fn sighandler(sig: c_int) callconv(.C) void {
logger.info("got signal {}; exiting...\n", .{sig});
quit = true;
}
pub fn main() !void {
// main heap allocator used throughout the lifetime of nd
var gpa_state = std.heap.GeneralPurposeAllocator(.{}){};
defer if (gpa_state.deinit()) {
logger.err("memory leaks detected", .{});
};
const gpa = gpa_state.allocator();
// parse program args first thing and fail fast if invalid
const args = try parseArgs(gpa);
defer args.deinit(gpa);
logger.info("ndg version {any}", .{buildopts.semver});
// reset the screen backlight to normal power regardless
// of its previous state.
screen.backlight(.on) catch |err| {
logger.err("backlight: {any}", .{err});
};
// start ngui, unless -nogui mode
var ngui = std.ChildProcess.init(&.{args.gui.?}, gpa);
ngui.stdin_behavior = .Pipe;
ngui.stdout_behavior = .Pipe;
ngui.stderr_behavior = .Inherit;
// fix zig std: child_process.zig:125:33: error: container 'std.os' has no member called 'getUserInfo'
//ngui.setUserName(args.gui_user) catch |err| {
// fatal("unable to set gui username to {s}: {s}", .{args.gui_user.?, err});
//};
// TODO: the following fails with "cannot open framebuffer device: Permission denied"
// but works with "doas -u uiuser ngui"
// ftr, zig uses setreuid and setregid
//const uiuser = std.process.getUserInfo(args.gui_user.?) catch |err| {
// fatal("unable to set gui username to {s}: {any}", .{ args.gui_user.?, err });
//};
//ngui.uid = uiuser.uid;
//ngui.gid = uiuser.gid;
// ngui.env_map = ...
ngui.spawn() catch |err| {
fatal("unable to start ngui: {any}", .{err});
};
// TODO: thread-safety, esp. uiwriter
const uireader = ngui.stdout.?.reader();
const uiwriter = ngui.stdin.?.writer();
// send UI a ping as the first thing to make sure pipes are working.
// https://git.qcode.ch/nakamochi/ndg/issues/16
comm.write(gpa, uiwriter, .ping) catch |err| {
logger.err("comm.write ping: {any}", .{err});
};
// graceful shutdown; see sigaction(2)
const sa = os.Sigaction{
.handler = .{ .handler = sighandler },
.mask = os.empty_sigset,
.flags = 0,
};
try os.sigaction(os.SIG.INT, &sa, null);
//TODO: try os.sigaction(os.SIG.TERM, &sa, null);
// start network monitor
var ctrl = try nif.wpa.Control.open(args.wpa.?);
defer ctrl.close() catch {};
var nd: Daemon = .{
.allocator = gpa,
.uiwriter = uiwriter,
.wpa_ctrl = ctrl,
};
try nd.start();
// send the UI network report right away, without scanning wifi
nd.reportNetworkStatus(.{ .scan = false });
// comm with ui loop; run until exit is requested
var poweroff = false;
while (!quit) {
time.sleep(100 * time.ns_per_ms);
// note: uireader.read is blocking
// TODO: handle error.EndOfStream - ngui exited
const msg = comm.read(gpa, uireader) catch |err| {
logger.err("comm.read: {any}", .{err});
continue;
};
logger.debug("got ui msg tagged {s}", .{@tagName(msg)});
switch (msg) {
.pong => {
logger.info("received pong from ngui", .{});
},
.poweroff => {
logger.info("poweroff requested; terminating", .{});
quit = true;
poweroff = true;
},
.get_network_report => |req| {
nd.reportNetworkStatus(.{ .scan = req.scan });
},
.wifi_connect => |req| {
nd.startConnectWifi(req.ssid, req.password) catch |err| {
logger.err("startConnectWifi: {any}", .{err});
};
},
.standby => {
logger.info("entering standby mode", .{});
nd.standby() catch |err| {
logger.err("nd.standby: {any}", .{err});
};
},
.wakeup => {
logger.info("wakeup from standby", .{});
nd.wakeup() catch |err| {
logger.err("nd.wakeup: {any}", .{err});
};
},
else => logger.warn("unhandled msg tag {s}", .{@tagName(msg)}),
}
comm.free(gpa, msg);
}
// shutdown
_ = ngui.kill() catch |err| logger.err("ngui.kill: {any}", .{err});
nd.stop();
if (poweroff) {
svShutdown(gpa);
var off = std.ChildProcess.init(&.{"poweroff"}, gpa);
_ = try off.spawnAndWait();
}
}
/// shut down important services manually.
/// TODO: make this OS-agnostic
fn svShutdown(allocator: std.mem.Allocator) void {
// sv waits 7sec by default but bitcoind and lnd need more
// http://smarden.org/runit/
const Argv = []const []const u8;
const cmds: []const Argv = &.{
&.{ "sv", "-w", "600", "stop", "lnd" },
&.{ "sv", "-w", "600", "stop", "bitcoind" },
};
var procs: [cmds.len]?std.ChildProcess = undefined;
for (cmds) |argv, i| {
var p = std.ChildProcess.init(argv, allocator);
if (p.spawn()) {
procs[i] = p;
} else |err| {
logger.err("{s}: {any}", .{ argv, err });
}
}
for (procs) |_, i| {
var p = procs[i];
if (p != null) {
_ = p.?.wait() catch |err| logger.err("{any}", .{err});
}
}
}