feat: support name probing and conflict resolution

Cargo.toml

@@ -3,7 +3,7 @@ name = "mdns-sd"
 version = "0.11.5"
 authors = ["keepsimple <[email protected]>"]
 edition = "2018"
-rust-version = "1.63.0"
+rust-version = "1.65.0"
 license = "Apache-2.0 OR MIT"
 repository = "https://github.com/keepsimple1/mdns-sd"
 documentation = "https://docs.rs/mdns-sd"
@@ -17,14 +17,15 @@ logging = ["log"]
 default = ["async", "logging"]
 
 [dependencies]
+fastrand = "2.1"
 flume = { version = "0.11", default-features = false } # channel between threads
 if-addrs = { version = "0.13", features = ["link-local"] } # get local IP addresses
 log = { version = "0.4", optional = true }             # logging
 polling = "2.1"                                        # select/poll sockets
 socket2 = { version = "0.5.5", features = ["all"] }      # socket APIs
 
 [dev-dependencies]
-env_logger = { version = "= 0.10.2", default-features = false, features= ["humantime"] }
+env_logger = "0.11"
 fastrand = "2.1"
 humantime = "2.1"
 test-log = "= 0.2.14"

examples/register.rs

@@ -2,11 +2,11 @@
 //!
 //! Run with:
 //!
-//! cargo run --example register <service_type> <instance_name>
+//! cargo run --example register <service_type> <instance_name> <hostname> [options]
 //!
 //! Example:
 //!
-//! cargo run --example register _my-hello._udp test1
+//! cargo run --example register _my-hello._udp instance1 host1
 //!
 //! Options:
 //! "--unregister": automatically unregister after 2 seconds.
@@ -16,7 +16,9 @@ use mdns_sd::{DaemonEvent, IfKind, ServiceDaemon, ServiceInfo};
 use std::{env, thread, time::Duration};
 
 fn main() {
-    env_logger::init();
+    // setup env_logger with more precise timestamp.
+    let mut builder = env_logger::Builder::from_default_env();
+    builder.format_timestamp_millis().init();
 
     // Simple command line options.
     let args: Vec<String> = env::args().collect();
@@ -52,11 +54,18 @@ fn main() {
             return;
         }
     };
+    let hostname = match args.get(3) {
+        Some(arg) => arg,
+        None => {
+            print_usage();
+            return;
+        }
+    };
 
     // With `enable_addr_auto()`, we can give empty addrs and let the lib find them.
     // If the caller knows specific addrs to use, then assign the addrs here.
     let my_addrs = "";
-    let service_hostname = format!("{}{}", instance_name, &service_type);
+    let service_hostname = format!("{}.local.", hostname);
     let port = 3456;
 
     // The key string in TXT properties is case insensitive. Only the first
@@ -106,10 +115,11 @@ fn main() {
 
 fn print_usage() {
     println!("Usage:");
-    println!("cargo run --example register <service_type> <instance_name> [--unregister]");
+    println!("cargo run --example register <service_type> <instance_name> <hostname> [options]");
     println!("Options:");
     println!("--unregister: automatically unregister after 2 seconds");
+    println!("--disable-ipv6: not to use IPv6 interfaces.");
     println!();
     println!("For example:");
-    println!("cargo run --example register _my-hello._udp test1");
+    println!("cargo run --example register _my-hello._udp instance1 host1");
 }

src/dns_cache.rs

@@ -277,7 +277,7 @@ impl DnsCache {
                         srv_records.retain(|srv| {
                             let expired = srv.get_record().is_expired(now);
                             if expired {
-                                debug!("expired SRV: {}: {}", ty_domain, srv.get_name());
+                                debug!("expired SRV: {}: {:?}", ty_domain, srv);
                                 expired_instances
                                     .entry(ty_domain.to_string())
                                     .or_insert_with(HashSet::new)
@@ -299,7 +299,7 @@ impl DnsCache {
                 let expired = x.get_record().is_expired(now);
                 if expired {
                     if let Some(dns_ptr) = x.any().downcast_ref::<DnsPointer>() {
-                        debug!("expired PTR: {:?}", dns_ptr);
+                        debug!("expired PTR: domain:{ty_domain} record: {:?}", dns_ptr);
                         expired_instances
                             .entry(ty_domain.to_string())
                             .or_insert_with(HashSet::new)