Merge pull request #210 from vibe-d/async_improvements

Remove potentially blocking file I/O code (upgrade to eventcore 0.9.0).

dub.sdl

@@ -4,7 +4,7 @@ authors "Sönke Ludwig"
 copyright "Copyright © 2016-2020, Sönke Ludwig"
 license "MIT"
 
-dependency "eventcore" version="~>0.8.43"
+dependency "eventcore" version="~>0.9.0"
 dependency "stdx-allocator" version="~>2.77.0"
 
 targetName "vibe_core"

source/vibe/core/file.d

@@ -190,16 +190,21 @@ void moveFile(NativePath from, NativePath to, bool copy_fallback = false)
 /// ditto
 void moveFile(string from, string to, bool copy_fallback = false)
 {
-	if (!copy_fallback) {
-		std.file.rename(from, to);
-	} else {
+	auto fail = performInWorker((string from, string to) {
 		try {
 			std.file.rename(from, to);
-		} catch (FileException e) {
-			copyFile(from, to);
-			std.file.remove(from);
+		} catch (Exception e) {
+			return e.msg.length ? e.msg : "Failed to move file.";
 		}
-	}
+		return null;
+	}, from, to);
+
+	if (!fail.length) return;
+
+	if (!copy_fallback) throw new Exception(fail);
+
+	copyFile(from, to);
+	removeFile(from);
 }
 
 /**
@@ -236,6 +241,7 @@ void copyFile(NativePath from, NativePath to, bool overwrite = false)
 		enforce(overwrite || !existsFile(to), "Destination file already exists.");
 		auto dst = openFile(to, FileMode.createTrunc);
 		scope(exit) dst.close();
+		dst.truncate(src.size);
 		dst.write(src);
 	}
 
@@ -267,7 +273,16 @@ void removeFile(NativePath path)
 /// ditto
 void removeFile(string path)
 {
-	std.file.remove(path);
+	auto fail = performInWorker((string path) {
+		try {
+			std.file.remove(path);
+		} catch (Exception e) {
+			return e.msg.length ? e.msg : "Failed to delete file.";
+		}
+		return null;
+	}, path);
+
+	if (fail.length) throw new Exception(fail);
 }
 
 /**
@@ -567,12 +582,18 @@ struct FileStream {
 	/// Closes the file handle.
 	void close()
 	{
-		if (m_fd != FileFD.init) {
-			eventDriver.files.close(m_fd); // FIXME: may leave dangling references!
-			releaseHandle!"files"(m_fd, m_ctx.driver);
-			m_fd = FileFD.init;
-			m_ctx = null;
-		}
+		if (m_fd == FileFD.invalid) return;
+		if (!eventDriver.files.isValid(m_fd)) return;
+
+		auto res = asyncAwaitUninterruptible!(FileCloseCallback,
+			cb => eventDriver.files.close(m_fd, cb)
+		);
+		releaseHandle!"files"(m_fd, m_ctx.driver);
+		m_fd = FileFD.invalid;
+		m_ctx = null;
+
+		if (res[1] != CloseStatus.ok)
+			throw new Exception("Failed to close file");
 	}
 
 	@property bool empty() const { assert(this.readable); return ctx.ptr >= ctx.size; }

source/vibe/core/internal/release.d

@@ -1,6 +1,7 @@
 module vibe.core.internal.release;
 
 import eventcore.core;
+import std.stdint : intptr_t;
 
 /// Release a handle in a thread-safe way
 void releaseHandle(string subsys, H)(H handle, shared(NativeEventDriver) drv)
@@ -19,8 +20,8 @@ void releaseHandle(string subsys, H)(H handle, shared(NativeEventDriver) drv)
 
 		// in case the destructor was called from a foreign thread,
 		// perform the release in the owner thread
-		drv.core.runInOwnerThread((h) {
-			__traits(getMember, eventDriver, subsys).releaseRef(cast(H)h);
-		}, cast(size_t)handle);
+		drv.core.runInOwnerThread((H handle) {
+			__traits(getMember, eventDriver, subsys).releaseRef(handle);
+		}, handle);
 	}
 }

tests/std.concurrency.d

@@ -7,6 +7,7 @@ module test;
 
 import vibe.core.core;
 import vibe.core.log;
+import std.algorithm;
 import std.concurrency;
 import core.atomic;
 import core.time;
@@ -18,9 +19,16 @@ shared watchdog_count = 0;
 void main()
 {
 	t1 = spawn({
-		// ensure that asynchronous operations run in parallel to receive()
+		// ensure that asynchronous operations can run in parallel to receive()
 		int wc = 0;
-		runTask({ while (true) { sleep(250.msecs); wc++; logInfo("Watchdog receiver %s", wc); } });
+		MonoTime stime = MonoTime.currTime;
+		runTask({
+			while (true) {
+				sleepUntil((wc + 1) * 250.msecs, stime, 200.msecs);
+				wc++;
+				logInfo("Watchdog receiver %s", wc);
+			}
+		});
 
 		bool finished = false;
 		try while (!finished) {
@@ -57,28 +65,30 @@ void main()
 	});
 
 	t2 = spawn({
+		MonoTime stime = MonoTime.currTime;
+
 		scope (failure) assert(false);
-		sleep(1.seconds());
+		sleepUntil(1.seconds, stime, 900.msecs);
 		logInfo("send Hello World");
 		t1.send("Hello, World!");
 
-		sleep(1.seconds());
+		sleepUntil(2.seconds, stime, 900.msecs);
 		logInfo("send int 1");
 		t1.send(1);
 
-		sleep(1.seconds());
+		sleepUntil(3.seconds, stime, 900.msecs);
 		logInfo("send double 1.2");
 		t1.send(1.2);
 
-		sleep(1.seconds());
+		sleepUntil(4.seconds, stime, 900.msecs);
 		logInfo("send int 2");
 		t1.send(2);
 
-		sleep(1.seconds());
+		sleepUntil(5.seconds, stime, 900.msecs);
 		logInfo("send 3xint 1 2 3");
 		t1.send(1, 2, 3);
 
-		sleep(1.seconds());
+		sleepUntil(6.seconds, stime, 900.msecs);
 		logInfo("send string Bye bye");
 		t1.send("Bye bye");
 
@@ -89,3 +99,12 @@ void main()
 
 	runApplication();
 }
+
+// corrects for small timing inaccuracies to avoid the counter
+// getting systematically out of sync when sleep timing is inaccurate
+void sleepUntil(Duration until, MonoTime start_time, Duration min_sleep)
+{
+	auto tm = MonoTime.currTime;
+	auto timeout = max(start_time - tm + until, min_sleep);
+	sleep(timeout);
+}