Auto merge of rust-lang#102193 - ferrocene:pa-remote-test-server-improvements, r=Mark-Simulacrum

Change argument handling in `remote-test-server` and add new flags

This PR updates `remote-test-server` to add two new flags:

* `--sequential` disables parallel test execution, accepting one connection at the time instead. We need this for Ferrocene as one of our emulators occasionally deadlocks when running multiple tests in parallel.
* `--bind <ip:port>` allows customizing the IP and port `remote-test-server` binds to, rather than using the default value.

While I was changing the flags, and [after chatting on what to do on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/remote-test-server.20flags),  I took this opportunity to cleanup argument handling in `remote-test-server`, which is a breaking change:

* The `verbose` argument has been renamed to the `--verbose` flag.
* The `remote` argument has been removed in favor of the `--bind 0.0.0.0:12345` flag. The only thing the argument did was to change the bound IP to 0.0.0.0, which can easily be replicated with `--bind` and also is not secure as our "remote" default.

I'm also open to keep the old arguments with deprecation warnings.

r? `@Mark-Simulacrum`

Author: bors

Diff for: src/bootstrap/CHANGELOG.md

@@ -13,6 +13,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Change the names for `dist` commands to match the component they generate. [#90684](https://github.com/rust-lang/rust/pull/90684)
 - The `build.fast-submodules` option has been removed. Fast submodule checkouts are enabled unconditionally. Automatic submodule handling can still be disabled with `build.submodules = false`.
 - Several unsupported `./configure` options have been removed: `optimize`, `parallel-compiler`. These can still be enabled with `--set`, although it isn't recommended.
+- `remote-test-server`'s `verbose` argument has been removed in favor of the `--verbose` flag
+- `remote-test-server`'s `remote` argument has been removed in favor of the `--bind` flag. Use `--bind 0.0.0.0:12345` to replicate the behavior of the `remote` argument.
 
 ### Non-breaking changes
 

Diff for: src/tools/remote-test-server/src/main.rs

@@ -12,6 +12,7 @@
 
 #[cfg(not(windows))]
 use std::fs::Permissions;
+use std::net::SocketAddr;
 #[cfg(not(windows))]
 use std::os::unix::prelude::*;
 
@@ -41,30 +42,44 @@ static TEST: AtomicUsize = AtomicUsize::new(0);
 
 #[derive(Copy, Clone)]
 struct Config {
-    pub remote: bool,
-    pub verbose: bool,
+    verbose: bool,
+    sequential: bool,
+    bind: SocketAddr,
 }
 
 impl Config {
     pub fn default() -> Config {
-        Config { remote: false, verbose: false }
+        Config {
+            verbose: false,
+            sequential: false,
+            bind: if cfg!(target_os = "android") || cfg!(windows) {
+                ([0, 0, 0, 0], 12345).into()
+            } else {
+                ([10, 0, 2, 15], 12345).into()
+            },
+        }
     }
 
     pub fn parse_args() -> Config {
         let mut config = Config::default();
 
         let args = env::args().skip(1);
+        let mut next_is_bind = false;
         for argument in args {
             match &argument[..] {
-                "remote" => {
-                    config.remote = true;
-                }
-                "verbose" | "-v" => {
-                    config.verbose = true;
+                bind if next_is_bind => {
+                    config.bind = t!(bind.parse());
+                    next_is_bind = false;
                 }
+                "--bind" => next_is_bind = true,
+                "--sequential" => config.sequential = true,
+                "--verbose" | "-v" => config.verbose = true,
                 arg => panic!("unknown argument: {}", arg),
             }
         }
+        if next_is_bind {
+            panic!("missing value for --bind");
+        }
 
         config
     }
@@ -81,13 +96,7 @@ fn main() {
 
     let config = Config::parse_args();
 
-    let bind_addr = if cfg!(target_os = "android") || cfg!(windows) || config.remote {
-        "0.0.0.0:12345"
-    } else {
-        "10.0.2.15:12345"
-    };
-
-    let listener = t!(TcpListener::bind(bind_addr));
+    let listener = t!(TcpListener::bind(config.bind));
     let (work, tmp): (PathBuf, PathBuf) = if cfg!(target_os = "android") {
         ("/data/tmp/work".into(), "/data/tmp/work/tmp".into())
     } else {
@@ -97,7 +106,7 @@ fn main() {
         tmp_dir.push("tmp");
         (work_dir, tmp_dir)
     };
-    println!("listening on {}!", bind_addr);
+    println!("listening on {}!", config.bind);
 
     t!(fs::create_dir_all(&work));
     t!(fs::create_dir_all(&tmp));
@@ -119,7 +128,12 @@ fn main() {
             let lock = lock.clone();
             let work = work.clone();
             let tmp = tmp.clone();
-            thread::spawn(move || handle_run(socket, &work, &tmp, &lock, config));
+            let f = move || handle_run(socket, &work, &tmp, &lock, config);
+            if config.sequential {
+                f();
+            } else {
+                thread::spawn(f);
+            }
         } else {
             panic!("unknown command {:?}", buf);
         }