1  use anyhow::Context;
 2  use clap::Parser;
 3  
 4  mod avahi;
 5  
 6  #[derive(Parser, Debug)]
 7  #[command(version)]
 8  struct Args {
 9      #[arg(long, default_value_t = 120)]
10      ttl: u32,
11      #[arg(long)]
12      fqdn: Option<String>,
13      #[arg(short, long)]
14      subdomain: Vec<String>,
15  }
16  
17  fn main() -> anyhow::Result<()> {
18      let args = Args::parse();
19  
20      if args.subdomain.is_empty() {
21          println!("no subdomains specified");
22          return Ok(());
23      }
24  
25      let conn = zbus::blocking::Connection::system().context("error connecting to system buss")?;
26      let server =
27          avahi::ServerProxyBlocking::new(&conn).context("error connecting to avahi-daemon")?;
28      let fqdn = if let Some(fqdn) = args.fqdn {
29          fqdn
30      } else {
31          server
32              .get_host_name_fqdn()
33              .context("error getting hostname fqdn from avahi-daemon")?
34      };
35  
36      let rdata = {
37          let mut rdata = Vec::new();
38          for label in fqdn.split(".") {
39              rdata.push(label.len() as u8);
40              rdata.extend(label.as_bytes());
41          }
42          rdata.push(0);
43          rdata
44      };
45  
46      let entry_group = server.entry_group_new()?;
47      for name in args.subdomain {
48          entry_group
49              .add_record(-1, -1, 0, &format!("{name}.{fqdn}"), 1, 5, args.ttl, &rdata)
50              .context("error adding cname record to entry group")?;
51      }
52      entry_group
53          .commit()
54          .context("error commiting entry group")?;
55  
56      let dbus_proxy = zbus::blocking::fdo::DBusProxy::new(&conn)?;
57      for signal in dbus_proxy.receive_name_owner_changed()? {
58          let args = signal.args()?;
59          if args.name() == "org.freedesktop.Avahi"
60              && args.new_owner().as_deref().unwrap_or("").is_empty()
61          {
62              println!("avahi-daemon exited; stopping");
63              break;
64          }
65      }
66      Ok(())
67  }