Lift non-blocking requirements for FileDescriptor (#33)

Sources/Venice/FileDescriptor.swift

@@ -10,29 +10,31 @@ import CLibdill
 /// such as a pipe or network socket.
 public final class FileDescriptor {
     /// File descriptor handle.
-    public private(set) var fileDescriptor: Int32
-
-    /// Creates a `FileDescriptor` from a file descriptor handle and
-    /// configures it as non-blocking.
+    public private(set) var handle: Int32
+
+    /// Creates a `FileDescriptor` from a file descriptor handle
     ///
     /// - Parameters:
     ///   - fileDescriptor: Previously opened file descriptor.
+    public init(handle: Int32) {
+        self.handle = handle
+    }
+
+    /// Configures the `FileDescriptor` to non-blocking
     ///
     /// - Throws: The following errors might be thrown:
     ///   #### VeniceError.invalidFileDescriptor
-    ///   Thrown when `fileDescriptor` is not an open file descriptor.
-    public init(_ fileDescriptor: Int32) throws {
-        let flags = fcntl(fileDescriptor, F_GETFL, 0)
-        
+    ///   Thrown when `handle` is not an open file descriptor.
+    public func setNonblocking() throws {
+        let flags = fcntl(handle, F_GETFL, 0)
+
         guard flags != -1 else {
             throw VeniceError.invalidFileDescriptor
         }
-        
-        guard fcntl(fileDescriptor, F_SETFL, flags | O_NONBLOCK) == 0 else {
+
+        guard fcntl(handle, F_SETFL, flags | O_NONBLOCK) == 0 else {
             throw VeniceError.invalidFileDescriptor
         }
-
-        self.fileDescriptor = fileDescriptor
     }
 
     deinit {
@@ -70,9 +72,9 @@ public final class FileDescriptor {
 
         switch event {
         case .read:
-            result = fdin(fileDescriptor, deadline.value)
+            result = fdin(handle, deadline.value)
         case .write:
-            result = fdout(fileDescriptor, deadline.value)
+            result = fdout(handle, deadline.value)
         }
 
         guard result == 0 else {
@@ -101,11 +103,11 @@ public final class FileDescriptor {
     /// third-party libraries, just before returning them back to
     /// their original owners. Otherwise the behavior is **undefined**.
     public func clean() {
-        guard fileDescriptor != -1 else {
+        guard handle != -1 else {
             return
         }
 
-        fdclean(fileDescriptor)
+        fdclean(handle)
     }
 
     /// Closes a file descriptor, so that it no longer refers to any
@@ -114,41 +116,41 @@ public final class FileDescriptor {
     /// (regardless of the file descriptor that was used to obtain the lock).
     ///
     /// - Warning:
-    /// If `fileDescriptor` is the last file descriptor referring to the underlying open
+    /// If `handle` is the last file descriptor referring to the underlying open
     /// file description, the resources associated with the
     /// open file description are freed; if the file descriptor was the last
     /// reference to a file which has been removed using `unlink`, the file
     /// is deleted.
     ///
     /// - Throws: The following errors might be thrown:
     ///   #### VeniceError.invalidFileDescriptor
-    ///   Thrown when `fileDescriptor` is not an open file descriptor.
+    ///   Thrown when `handle` is not an open file descriptor.
     public func close() throws {
         clean()
 
         #if os(Linux)
-            guard Glibc.close(fileDescriptor) == 0 else {
+            guard Glibc.close(handle) == 0 else {
                 throw VeniceError.invalidFileDescriptor
             }
         #else
-            guard Darwin.close(fileDescriptor) == 0 else {
+            guard Darwin.close(handle) == 0 else {
                 throw VeniceError.invalidFileDescriptor
             }
         #endif
     }
 
-    /// Detaches the underlying `fileDescriptor`.
+    /// Detaches the underlying `handle`.
     /// After `detach` any operation will throw an error.
     ///
     /// - Returns: The underlying file descriptor.
     @discardableResult public func detach() -> Int32 {
         clean()
 
         defer {
-            fileDescriptor = -1
+            handle = -1
         }
 
-        return fileDescriptor
+        return handle
     }
 
     /// Event used to poll file descriptors for reading or writing.

Tests/VeniceTests/Venice/CoroutineTests.swift

@@ -119,22 +119,24 @@ public class CoroutineTests : XCTestCase {
             error: VeniceError.deadlineReached
         )
 
-        var size = send(socket2.fileDescriptor, "A", 1, 0)
+        var size = send(socket2.handle, "A", 1, 0)
         XCTAssert(size == 1)
 
         try socket1.poll(event: .write, deadline: 100.milliseconds.fromNow())
         try socket1.poll(event: .read, deadline: 100.milliseconds.fromNow())
 
         var character: Int8 = 0
-        size = recv(socket1.fileDescriptor, &character, 1, 0)
+        size = recv(socket1.handle, &character, 1, 0)
 
         XCTAssert(size == 1)
         XCTAssert(character == 65)
     }
 
     func testInvalidFileDescriptor() throws {
+        let fd = FileDescriptor(handle: -1)
+
         XCTAssertThrowsError(
-            try FileDescriptor(-1),
+            try fd.setNonblocking(),
             error: VeniceError.invalidFileDescriptor
         )
     }
@@ -174,7 +176,7 @@ public class CoroutineTests : XCTestCase {
     }
 
     func testCleanFileDescriptor() throws {
-        let fileDescriptor = try FileDescriptor(STDIN_FILENO)
+        let fileDescriptor = FileDescriptor(handle: STDIN_FILENO)
         fileDescriptor.clean()
     }
 
@@ -189,10 +191,10 @@ public class CoroutineTests : XCTestCase {
 
         XCTAssert(result == 0)
 
-        let fileDescriptor = try FileDescriptor(sockets[0])
+        let fileDescriptor = FileDescriptor(handle: sockets[0])
         let standardInput = fileDescriptor.detach()
         XCTAssertEqual(standardInput, sockets[0])
-        XCTAssertEqual(fileDescriptor.fileDescriptor, -1)
+        XCTAssertEqual(fileDescriptor.handle, -1)
 
         XCTAssertThrowsError(
             try fileDescriptor.poll(event: .read, deadline: .never),
@@ -212,7 +214,7 @@ func createSocketPair() throws -> (FileDescriptor, FileDescriptor) {
 
     XCTAssert(result == 0)
 
-    return try (FileDescriptor(sockets[0]), FileDescriptor(sockets[1]))
+    return (FileDescriptor(handle: sockets[0]), FileDescriptor(handle: sockets[1]))
 }
 
 extension CoroutineTests {