1 //! This is a small server which is intended to run inside of an emulator or
2 //! on a remote test device. This server pairs with the `remote-test-client`
3 //! program in this repository. The `remote-test-client` connects to this
4 //! server over a TCP socket and performs work such as:
5 //!
6 //! 1. Pushing shared libraries to the server
7 //! 2. Running tests through the server
8 //!
9 //! The server supports running tests concurrently and also supports tests
10 //! themselves having support libraries. All data over the TCP sockets is in a
11 //! basically custom format suiting our needs.
12
13 #[cfg(not(windows))]
14 use std::fs::Permissions;
15 use std::net::SocketAddr;
16 #[cfg(not(windows))]
17 use std::os::unix::prelude::*;
18
19 use std::cmp;
20 use std::env;
21 use std::fs::{self, File};
22 use std::io::prelude::*;
23 use std::io::{self, BufReader};
24 use std::net::{TcpListener, TcpStream};
25 use std::path::{Path, PathBuf};
26 use std::process::{Command, ExitStatus, Stdio};
27 use std::str;
28 use std::sync::atomic::{AtomicUsize, Ordering};
29 use std::sync::{Arc, Mutex};
30 use std::thread;
31
32 macro_rules! t {
33 ($e:expr) => {
34 match $e {
35 Ok(e) => e,
36 Err(e) => panic!("{} failed with {}", stringify!($e), e),
37 }
38 };
39 }
40
41 static TEST: AtomicUsize = AtomicUsize::new(0);
42 const RETRY_INTERVAL: u64 = 1;
43 const NUMBER_OF_RETRIES: usize = 5;
44
45 #[derive(Copy, Clone)]
46 struct Config {
47 verbose: bool,
48 sequential: bool,
49 batch: bool,
50 bind: SocketAddr,
51 }
52
53 impl Config {
default() -> Config54 pub fn default() -> Config {
55 Config {
56 verbose: false,
57 sequential: false,
58 batch: false,
59 bind: if cfg!(target_os = "android") || cfg!(windows) {
60 ([0, 0, 0, 0], 12345).into()
61 } else {
62 ([10, 0, 2, 15], 12345).into()
63 },
64 }
65 }
66
parse_args() -> Config67 pub fn parse_args() -> Config {
68 let mut config = Config::default();
69
70 let args = env::args().skip(1);
71 let mut next_is_bind = false;
72 for argument in args {
73 match &argument[..] {
74 bind if next_is_bind => {
75 config.bind = t!(bind.parse());
76 next_is_bind = false;
77 }
78 "--bind" => next_is_bind = true,
79 "--sequential" => config.sequential = true,
80 "--batch" => config.batch = true,
81 "--verbose" | "-v" => config.verbose = true,
82 "--help" | "-h" => {
83 show_help();
84 std::process::exit(0);
85 }
86 arg => panic!("unknown argument: {}, use `--help` for known arguments", arg),
87 }
88 }
89 if next_is_bind {
90 panic!("missing value for --bind");
91 }
92
93 config
94 }
95 }
96
show_help()97 fn show_help() {
98 eprintln!(
99 r#"Usage:
100
101 {} [OPTIONS]
102
103 OPTIONS:
104 --bind <IP>:<PORT> Specify IP address and port to listen for requests, e.g. "0.0.0.0:12345"
105 --sequential Run only one test at a time
106 --batch Send stdout and stderr in batch instead of streaming
107 -v, --verbose Show status messages
108 -h, --help Show this help screen
109 "#,
110 std::env::args().next().unwrap()
111 );
112 }
113
print_verbose(s: &str, conf: Config)114 fn print_verbose(s: &str, conf: Config) {
115 if conf.verbose {
116 println!("{}", s);
117 }
118 }
119
main()120 fn main() {
121 let config = Config::parse_args();
122 println!("starting test server");
123
124 let listener = bind_socket(config.bind);
125 let (work, tmp): (PathBuf, PathBuf) = if cfg!(target_os = "android") {
126 ("/data/local/tmp/work".into(), "/data/local/tmp/work/tmp".into())
127 } else {
128 let mut work_dir = env::temp_dir();
129 work_dir.push("work");
130 let mut tmp_dir = work_dir.clone();
131 tmp_dir.push("tmp");
132 (work_dir, tmp_dir)
133 };
134 println!("listening on {}!", config.bind);
135
136 t!(fs::create_dir_all(&work));
137 t!(fs::create_dir_all(&tmp));
138
139 let lock = Arc::new(Mutex::new(()));
140
141 for socket in listener.incoming() {
142 let mut socket = t!(socket);
143 let mut buf = [0; 4];
144 if socket.read_exact(&mut buf).is_err() {
145 continue;
146 }
147 if &buf[..] == b"ping" {
148 print_verbose("Received ping", config);
149 t!(socket.write_all(b"pong"));
150 } else if &buf[..] == b"push" {
151 handle_push(socket, &work, config);
152 } else if &buf[..] == b"run " {
153 let lock = lock.clone();
154 let work = work.clone();
155 let tmp = tmp.clone();
156 let f = move || handle_run(socket, &work, &tmp, &lock, config);
157 if config.sequential {
158 f();
159 } else {
160 thread::spawn(f);
161 }
162 } else {
163 panic!("unknown command {:?}", buf);
164 }
165 }
166 }
167
bind_socket(addr: SocketAddr) -> TcpListener168 fn bind_socket(addr: SocketAddr) -> TcpListener {
169 for _ in 0..(NUMBER_OF_RETRIES - 1) {
170 if let Ok(x) = TcpListener::bind(addr) {
171 return x;
172 }
173 std::thread::sleep(std::time::Duration::from_secs(RETRY_INTERVAL));
174 }
175 TcpListener::bind(addr).unwrap()
176 }
177
handle_push(socket: TcpStream, work: &Path, config: Config)178 fn handle_push(socket: TcpStream, work: &Path, config: Config) {
179 let mut reader = BufReader::new(socket);
180 let dst = recv(&work, &mut reader);
181 print_verbose(&format!("push {:#?}", dst), config);
182
183 let mut socket = reader.into_inner();
184 t!(socket.write_all(b"ack "));
185 }
186
187 struct RemoveOnDrop<'a> {
188 inner: &'a Path,
189 }
190
191 impl Drop for RemoveOnDrop<'_> {
drop(&mut self)192 fn drop(&mut self) {
193 t!(fs::remove_dir_all(self.inner));
194 }
195 }
196
handle_run(socket: TcpStream, work: &Path, tmp: &Path, lock: &Mutex<()>, config: Config)197 fn handle_run(socket: TcpStream, work: &Path, tmp: &Path, lock: &Mutex<()>, config: Config) {
198 let mut arg = Vec::new();
199 let mut reader = BufReader::new(socket);
200
201 // Allocate ourselves a directory that we'll delete when we're done to save
202 // space.
203 let n = TEST.fetch_add(1, Ordering::SeqCst);
204 let path = work.join(format!("test{}", n));
205 t!(fs::create_dir(&path));
206 let _a = RemoveOnDrop { inner: &path };
207
208 // First up we'll get a list of arguments delimited with 0 bytes. An empty
209 // argument means that we're done.
210 let mut args = Vec::new();
211 while t!(reader.read_until(0, &mut arg)) > 1 {
212 args.push(t!(str::from_utf8(&arg[..arg.len() - 1])).to_string());
213 arg.truncate(0);
214 }
215
216 // Next we'll get a bunch of env vars in pairs delimited by 0s as well
217 let mut env = Vec::new();
218 arg.truncate(0);
219 while t!(reader.read_until(0, &mut arg)) > 1 {
220 let key_len = arg.len() - 1;
221 let val_len = t!(reader.read_until(0, &mut arg)) - 1;
222 {
223 let key = &arg[..key_len];
224 let val = &arg[key_len + 1..][..val_len];
225 let key = t!(str::from_utf8(key)).to_string();
226 let val = t!(str::from_utf8(val)).to_string();
227 env.push((key, val));
228 }
229 arg.truncate(0);
230 }
231
232 // The section of code from here down to where we drop the lock is going to
233 // be a critical section for us. On Linux you can't execute a file which is
234 // open somewhere for writing, as you'll receive the error "text file busy".
235 // Now here we never have the text file open for writing when we spawn it,
236 // so why do we still need a critical section?
237 //
238 // Process spawning first involves a `fork` on Unix, which clones all file
239 // descriptors into the child process. This means that it's possible for us
240 // to open the file for writing (as we're downloading it), then some other
241 // thread forks, then we close the file and try to exec. At that point the
242 // other thread created a child process with the file open for writing, and
243 // we attempt to execute it, so we get an error.
244 //
245 // This race is resolve by ensuring that only one thread can write the file
246 // and spawn a child process at once. Kinda an unfortunate solution, but we
247 // don't have many other choices with this sort of setup!
248 //
249 // In any case the lock is acquired here, before we start writing any files.
250 // It's then dropped just after we spawn the child. That way we don't lock
251 // the execution of the child, just the creation of its files.
252 let lock = lock.lock();
253
254 // Next there's a list of dynamic libraries preceded by their filenames.
255 while t!(reader.fill_buf())[0] != 0 {
256 recv(&path, &mut reader);
257 }
258 assert_eq!(t!(reader.read(&mut [0])), 1);
259
260 // Finally we'll get the binary. The other end will tell us how big the
261 // binary is and then we'll download it all to the exe path we calculated
262 // earlier.
263 let exe = recv(&path, &mut reader);
264 print_verbose(&format!("run {:#?}", exe), config);
265
266 let mut cmd = Command::new(&exe);
267 cmd.args(args);
268 cmd.envs(env);
269
270 // On windows, libraries are just searched in the executable directory,
271 // system directories, PWD, and PATH, in that order. PATH is the only one
272 // we can change for this.
273 let library_path = if cfg!(windows) { "PATH" } else { "LD_LIBRARY_PATH" };
274
275 // Support libraries were uploaded to `work` earlier, so make sure that's
276 // in `LD_LIBRARY_PATH`. Also include our own current dir which may have
277 // had some libs uploaded.
278 let mut paths = vec![work.to_owned(), path.clone()];
279 if let Some(library_path) = env::var_os(library_path) {
280 paths.extend(env::split_paths(&library_path));
281 }
282 cmd.env(library_path, env::join_paths(paths).unwrap());
283
284 // Some tests assume RUST_TEST_TMPDIR exists
285 cmd.env("RUST_TEST_TMPDIR", tmp.to_owned());
286
287 let socket = Arc::new(Mutex::new(reader.into_inner()));
288
289 let status = if config.batch {
290 let child =
291 t!(cmd.stdin(Stdio::null()).stdout(Stdio::piped()).stderr(Stdio::piped()).output());
292 batch_copy(&child.stdout, 0, &*socket);
293 batch_copy(&child.stderr, 1, &*socket);
294 child.status
295 } else {
296 // Spawn the child and ferry over stdout/stderr to the socket in a framed
297 // fashion (poor man's style)
298 let mut child =
299 t!(cmd.stdin(Stdio::null()).stdout(Stdio::piped()).stderr(Stdio::piped()).spawn());
300 drop(lock);
301 let mut stdout = child.stdout.take().unwrap();
302 let mut stderr = child.stderr.take().unwrap();
303 let socket2 = socket.clone();
304 let thread = thread::spawn(move || my_copy(&mut stdout, 0, &*socket2));
305 my_copy(&mut stderr, 1, &*socket);
306 thread.join().unwrap();
307 t!(child.wait())
308 };
309
310 // Finally send over the exit status.
311 let (which, code) = get_status_code(&status);
312
313 t!(socket.lock().unwrap().write_all(&[
314 which,
315 (code >> 24) as u8,
316 (code >> 16) as u8,
317 (code >> 8) as u8,
318 (code >> 0) as u8,
319 ]));
320 }
321
322 #[cfg(not(windows))]
get_status_code(status: &ExitStatus) -> (u8, i32)323 fn get_status_code(status: &ExitStatus) -> (u8, i32) {
324 match status.code() {
325 Some(n) => (0, n),
326 None => (1, status.signal().unwrap()),
327 }
328 }
329
330 #[cfg(windows)]
get_status_code(status: &ExitStatus) -> (u8, i32)331 fn get_status_code(status: &ExitStatus) -> (u8, i32) {
332 (0, status.code().unwrap())
333 }
334
recv<B: BufRead>(dir: &Path, io: &mut B) -> PathBuf335 fn recv<B: BufRead>(dir: &Path, io: &mut B) -> PathBuf {
336 let mut filename = Vec::new();
337 t!(io.read_until(0, &mut filename));
338
339 // We've got some tests with *really* long names. We try to name the test
340 // executable the same on the target as it is on the host to aid with
341 // debugging, but the targets we're emulating are often more restrictive
342 // than the hosts as well.
343 //
344 // To ensure we can run a maximum number of tests without modifications we
345 // just arbitrarily truncate the filename to 50 bytes. That should
346 // hopefully allow us to still identify what's running while staying under
347 // the filesystem limits.
348 let len = cmp::min(filename.len() - 1, 50);
349 let dst = dir.join(t!(str::from_utf8(&filename[..len])));
350 let amt = read_u32(io) as u64;
351 t!(io::copy(&mut io.take(amt), &mut t!(File::create(&dst))));
352 set_permissions(&dst);
353 dst
354 }
355
356 #[cfg(not(windows))]
set_permissions(path: &Path)357 fn set_permissions(path: &Path) {
358 t!(fs::set_permissions(&path, Permissions::from_mode(0o755)));
359 }
360 #[cfg(windows)]
set_permissions(_path: &Path)361 fn set_permissions(_path: &Path) {}
362
my_copy(src: &mut dyn Read, which: u8, dst: &Mutex<dyn Write>)363 fn my_copy(src: &mut dyn Read, which: u8, dst: &Mutex<dyn Write>) {
364 let mut b = [0; 1024];
365 loop {
366 let n = t!(src.read(&mut b));
367 let mut dst = dst.lock().unwrap();
368 t!(dst.write_all(&create_header(which, n as u32)));
369 if n > 0 {
370 t!(dst.write_all(&b[..n]));
371 } else {
372 break;
373 }
374 }
375 }
376
batch_copy(buf: &[u8], which: u8, dst: &Mutex<dyn Write>)377 fn batch_copy(buf: &[u8], which: u8, dst: &Mutex<dyn Write>) {
378 let n = buf.len();
379 let mut dst = dst.lock().unwrap();
380 t!(dst.write_all(&create_header(which, n as u32)));
381 if n > 0 {
382 t!(dst.write_all(buf));
383 // Marking buf finished
384 t!(dst.write_all(&[which, 0, 0, 0, 0,]));
385 }
386 }
387
create_header(which: u8, n: u32) -> [u8; 5]388 const fn create_header(which: u8, n: u32) -> [u8; 5] {
389 let bytes = n.to_be_bytes();
390 [which, bytes[0], bytes[1], bytes[2], bytes[3]]
391 }
392
read_u32(r: &mut dyn Read) -> u32393 fn read_u32(r: &mut dyn Read) -> u32 {
394 let mut len = [0; 4];
395 t!(r.read_exact(&mut len));
396 u32::from_be_bytes(len)
397 }
398