NSTask - capture output from commands (#348)

* Implemented NSFileHandle.availableData

* Redirect stdin, stdout and stderr for NSTask

* [NSTask] Use precondition instead of abort

Author: Bouke

Foundation.xcodeproj/project.pbxproj

@@ -274,6 +274,8 @@
 		D3E8D6D31C36982700295652 /* NSKeyedUnarchiver-EdgeInsetsTest.plist in Resources */ = {isa = PBXBuildFile; fileRef = D3E8D6D21C36982700295652 /* NSKeyedUnarchiver-EdgeInsetsTest.plist */; };
 		D3E8D6D51C36AC0C00295652 /* NSKeyedUnarchiver-RectTest.plist in Resources */ = {isa = PBXBuildFile; fileRef = D3E8D6D41C36AC0C00295652 /* NSKeyedUnarchiver-RectTest.plist */; };
 		D5C40F331CDA1D460005690C /* TestNSOperationQueue.swift in Sources */ = {isa = PBXBuildFile; fileRef = D5C40F321CDA1D460005690C /* TestNSOperationQueue.swift */; };
+		D51239DF1CD9DA0800D433EE /* CFSocket.c in Sources */ = {isa = PBXBuildFile; fileRef = 5B5D88E01BBC9B0300234F36 /* CFSocket.c */; };
+		D512D17C1CD883F00032E6A5 /* TestNSFileHandle.swift in Sources */ = {isa = PBXBuildFile; fileRef = D512D17B1CD883F00032E6A5 /* TestNSFileHandle.swift */; };
 		E1A03F361C4828650023AF4D /* PropertyList-1.0.dtd in Resources */ = {isa = PBXBuildFile; fileRef = E1A03F351C4828650023AF4D /* PropertyList-1.0.dtd */; };
 		E1A03F381C482C730023AF4D /* NSXMLDTDTestData.xml in Resources */ = {isa = PBXBuildFile; fileRef = E1A03F371C482C730023AF4D /* NSXMLDTDTestData.xml */; };
 		E1A3726F1C31EBFB0023AF4D /* NSXMLDocumentTestData.xml in Resources */ = {isa = PBXBuildFile; fileRef = E1A3726E1C31EBFB0023AF4D /* NSXMLDocumentTestData.xml */; };
@@ -648,6 +650,7 @@
 		D3E8D6D21C36982700295652 /* NSKeyedUnarchiver-EdgeInsetsTest.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "NSKeyedUnarchiver-EdgeInsetsTest.plist"; sourceTree = "<group>"; };
 		D3E8D6D41C36AC0C00295652 /* NSKeyedUnarchiver-RectTest.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "NSKeyedUnarchiver-RectTest.plist"; sourceTree = "<group>"; };
 		D5C40F321CDA1D460005690C /* TestNSOperationQueue.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TestNSOperationQueue.swift; sourceTree = "<group>"; };
+		D512D17B1CD883F00032E6A5 /* TestNSFileHandle.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TestNSFileHandle.swift; sourceTree = "<group>"; };
 		D834F9931C31C4060023812A /* TestNSOrderedSet.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TestNSOrderedSet.swift; sourceTree = "<group>"; };
 		DCDBB8321C1768AC00313299 /* TestNSData.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TestNSData.swift; sourceTree = "<group>"; };
 		E19E17DB1C2225930023AF4D /* TestNSXMLDocument.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TestNSXMLDocument.swift; sourceTree = "<group>"; };
@@ -1219,6 +1222,7 @@
 				5B6F17961C48631C00935030 /* TestUtils.swift */,
 				E19E17DB1C2225930023AF4D /* TestNSXMLDocument.swift */,
 				294E3C1C1CC5E19300E4F44C /* TestNSAttributedString.swift */,
+				D512D17B1CD883F00032E6A5 /* TestNSFileHandle.swift */,
 			);
 			name = Tests;
 			sourceTree = "<group>";
@@ -1907,6 +1911,7 @@
 				5B7C8A921BEA7FEC00C5B690 /* CFXMLInputStream.c in Sources */,
 				5B7C8AAA1BEA800D00C5B690 /* CFBurstTrie.c in Sources */,
 				5B7C8A9E1BEA7FF900C5B690 /* CFPlugIn_Instance.c in Sources */,
+				D51239DF1CD9DA0800D433EE /* CFSocket.c in Sources */,
 				5B7C8A801BEA7FCE00C5B690 /* CFDictionary.c in Sources */,
 				5BC2C00F1C07833200CC214E /* CFStringTransform.c in Sources */,
 				5B7C8AAE1BEA800D00C5B690 /* CFStringScanner.c in Sources */,
@@ -1997,6 +2002,7 @@
 				5B13B3401C582D4C00651CE2 /* TestNSRange.swift in Sources */,
 				5B13B3371C582D4C00651CE2 /* TestNSNotificationCenter.swift in Sources */,
 				5B13B3251C582D4700651CE2 /* main.swift in Sources */,
+				D512D17C1CD883F00032E6A5 /* TestNSFileHandle.swift in Sources */,
 				5B13B33A1C582D4C00651CE2 /* TestNSNumber.swift in Sources */,
 				5B13B3521C582D4C00651CE2 /* TestNSValue.swift in Sources */,
 				5B13B3311C582D4C00651CE2 /* TestNSIndexPath.swift in Sources */,

Foundation/NSFileHandle.swift

@@ -20,15 +20,19 @@ public class NSFileHandle : NSObject, NSSecureCoding {
     internal var _closeOnDealloc: Bool
     internal var _closed: Bool = false
 
-    /*@NSCopying*/ public var availableData: NSData {
-        NSUnimplemented()
+    public var availableData: NSData {
+        return _readDataOfLength(Int.max, untilEOF: false)
     }
 
     public func readDataToEndOfFile() -> NSData {
         return readDataOfLength(Int.max)
     }
-    
+
     public func readDataOfLength(_ length: Int) -> NSData {
+        return _readDataOfLength(length, untilEOF: true)
+    }
+
+    internal func _readDataOfLength(_ length: Int, untilEOF: Bool) -> NSData {
         var statbuf = stat()
         var dynamicBuffer: UnsafeMutablePointer<UInt8>? = nil
         var total = 0
@@ -49,21 +53,21 @@ public class NSFileHandle : NSObject, NSSecureCoding {
                     if dynamicBuffer == nil {
                         fatalError("unable to allocate backing buffer")
                     }
-                    let amtRead = read(_fd, dynamicBuffer!.advanced(by: total), amountToRead)
-                    if 0 > amtRead {
-                        free(dynamicBuffer)
-                        fatalError("read failure")
-                    }
-                    if 0 == amtRead {
-                        break // EOF
-                    }
-                    
-                    total += amtRead
-                    remaining -= amtRead
-                    
-                    if total == length {
-                        break // We read everything the client asked for.
-                    }
+                }
+                let amtRead = read(_fd, dynamicBuffer!.advanced(by: total), amountToRead)
+                if 0 > amtRead {
+                    free(dynamicBuffer)
+                    fatalError("read failure")
+                }
+                if 0 == amtRead {
+                    break // EOF
+                }
+                
+                total += amtRead
+                remaining -= amtRead
+                
+                if total == length || !untilEOF {
+                    break // We read everything the client asked for.
                 }
             }
         } else {

Foundation/NSTask.swift

@@ -151,9 +151,24 @@ public class NSTask : NSObject {
     public var currentDirectoryPath: String = NSFileManager.defaultInstance.currentDirectoryPath
 
     // standard I/O channels; could be either an NSFileHandle or an NSPipe
-    public var standardInput: AnyObject?
-    public var standardOutput: AnyObject?
-    public var standardError: AnyObject?
+    public var standardInput: AnyObject? {
+        willSet {
+            precondition(newValue is NSPipe || newValue is NSFileHandle,
+                         "standardInput must be either NSPipe or NSFileHandle")
+        }
+    }
+    public var standardOutput: AnyObject? {
+        willSet {
+            precondition(newValue is NSPipe || newValue is NSFileHandle,
+                         "standardOutput must be either NSPipe or NSFileHandle")
+        }
+    }
+    public var standardError: AnyObject? {
+        willSet {
+            precondition(newValue is NSPipe || newValue is NSFileHandle,
+                         "standardError must be either NSPipe or NSFileHandle")
+        }
+    }
 
     private var runLoopSourceContext : CFRunLoopSourceContext?
     private var runLoopSource : CFRunLoopSource?
@@ -284,16 +299,68 @@ public class NSTask : NSObject {
 
         let source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, socket, 0)
         CFRunLoopAddSource(managerThreadRunLoop?._cfRunLoop, source, kCFRunLoopDefaultMode)
-        
+
+        // file_actions
+        #if os(OSX) || os(iOS)
+            var fileActions: posix_spawn_file_actions_t? = nil
+        #else
+            var fileActions: posix_spawn_file_actions_t = posix_spawn_file_actions_t()
+        #endif
+        posix_spawn_file_actions_init(&fileActions)
+
+        switch self.standardInput {
+        case let pipe as NSPipe:
+            posix_spawn_file_actions_adddup2(&fileActions, pipe.fileHandleForReading.fileDescriptor, STDIN_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, pipe.fileHandleForWriting.fileDescriptor)
+        case let handle as NSFileHandle:
+            posix_spawn_file_actions_adddup2(&fileActions, handle.fileDescriptor, STDIN_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, handle.fileDescriptor)
+        default: break
+        }
+
+        switch self.standardOutput {
+        case let pipe as NSPipe:
+            posix_spawn_file_actions_adddup2(&fileActions, pipe.fileHandleForWriting.fileDescriptor, STDOUT_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, pipe.fileHandleForWriting.fileDescriptor)
+        case let handle as NSFileHandle:
+            posix_spawn_file_actions_adddup2(&fileActions, handle.fileDescriptor, STDOUT_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, handle.fileDescriptor)
+        default: break
+        }
+
+        switch self.standardError {
+        case let pipe as NSPipe:
+            posix_spawn_file_actions_adddup2(&fileActions, pipe.fileHandleForWriting.fileDescriptor, STDERR_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, pipe.fileHandleForWriting.fileDescriptor)
+        case let handle as NSFileHandle:
+            posix_spawn_file_actions_adddup2(&fileActions, handle.fileDescriptor, STDERR_FILENO)
+            posix_spawn_file_actions_addclose(&fileActions, handle.fileDescriptor)
+        default: break
+        }
+
         // Launch
-        
+
         var pid = pid_t()
-        let status = posix_spawn(&pid, launchPath, nil, nil, argv, envp)
-        
+        let status = posix_spawn(&pid, launchPath, &fileActions, nil, argv, envp)
+
+        // cleanup file_actions
+        posix_spawn_file_actions_destroy(&fileActions)
+
+        // Close the write end of the input and output pipes.
+        if let pipe = self.standardInput as? NSPipe {
+            pipe.fileHandleForReading.closeFile()
+        }
+        if let pipe = self.standardOutput as? NSPipe {
+            pipe.fileHandleForWriting.closeFile()
+        }
+        if let pipe = self.standardError as? NSPipe {
+            pipe.fileHandleForWriting.closeFile()
+        }
+
         guard status == 0 else {
             fatalError()
         }
-        
+
         close(taskSocketPair[1])
 
         self.runLoop = NSRunLoop.currentRunLoop()

TestFoundation/TestNSFileHandle.swift

@@ -0,0 +1,41 @@
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2016 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+
+#if DEPLOYMENT_RUNTIME_OBJC || os(Linux)
+    import Foundation
+    import XCTest
+#else
+    import SwiftFoundation
+    import SwiftXCTest
+#endif
+
+class TestNSFileHandle : XCTestCase {
+    static var allTests : [(String, TestNSFileHandle -> () throws -> ())] {
+        return [
+                   ("test_pipe", test_pipe),
+        ]
+    }
+
+    func test_pipe() {
+        let pipe = NSPipe()
+        let inputs = ["Hello", "world", "🐶"]
+
+        for input in inputs {
+            let inputData = input.data(using: NSUTF8StringEncoding)!
+
+            // write onto pipe
+            pipe.fileHandleForWriting.writeData(inputData)
+
+            let outputData = pipe.fileHandleForReading.availableData
+            let output = String(data: outputData, encoding: NSUTF8StringEncoding)
+
+            XCTAssertEqual(output, input)
+        }
+    }
+}

TestFoundation/TestNSTask.swift

@@ -18,11 +18,17 @@ import CoreFoundation
 
 class TestNSTask : XCTestCase {
     static var allTests: [(String, TestNSTask -> () throws -> Void)] {
-        return [("test_exit0" , test_exit0),
-                ("test_exit1" , test_exit1),
-                ("test_exit100" , test_exit100),
-                ("test_sleep2", test_sleep2),
-                ("test_sleep2_exit1", test_sleep2_exit1)]
+        return [
+                   ("test_exit0" , test_exit0),
+                   ("test_exit1" , test_exit1),
+                   ("test_exit100" , test_exit100),
+                   ("test_sleep2", test_sleep2),
+                   ("test_sleep2_exit1", test_sleep2_exit1),
+                   ("test_pipe_stdin", test_pipe_stdin),
+                   ("test_pipe_stdout", test_pipe_stdout),
+                   ("test_pipe_stderr", test_pipe_stderr),
+                   ("test_file_stdout", test_file_stdout),
+        ]
     }
 
     func test_exit0() {
@@ -84,4 +90,111 @@ class TestNSTask : XCTestCase {
         task.waitUntilExit()
         XCTAssertEqual(task.terminationStatus, 1)
     }
+
+
+    func test_pipe_stdin() {
+        let task = NSTask()
+
+        task.launchPath = "/bin/cat"
+
+        let outputPipe = NSPipe()
+        task.standardOutput = outputPipe
+
+        let inputPipe = NSPipe()
+        task.standardInput = inputPipe
+
+        task.launch()
+
+        inputPipe.fileHandleForWriting.writeData("Hello, 🐶.\n".data(using: NSUTF8StringEncoding)!)
+
+        // Close the input pipe to send EOF to cat.
+        inputPipe.fileHandleForWriting.closeFile()
+
+        task.waitUntilExit()
+        XCTAssertEqual(task.terminationStatus, 0)
+
+        let data = outputPipe.fileHandleForReading.availableData
+        guard let string = String(data: data, encoding: NSUTF8StringEncoding) else {
+            XCTFail("Could not read stdout")
+            return
+        }
+        XCTAssertEqual(string, "Hello, 🐶.\n")
+    }
+
+    func test_pipe_stdout() {
+        let task = NSTask()
+
+        task.launchPath = "/usr/bin/which"
+        task.arguments = ["which"]
+
+        let pipe = NSPipe()
+        task.standardOutput = pipe
+
+        task.launch()
+        task.waitUntilExit()
+        XCTAssertEqual(task.terminationStatus, 0)
+
+        let data = pipe.fileHandleForReading.availableData
+        guard let string = String(data: data, encoding: NSASCIIStringEncoding) else {
+            XCTFail("Could not read stdout")
+            return
+        }
+        XCTAssertEqual(string, "/usr/bin/which\n")
+    }
+
+    func test_pipe_stderr() {
+        let task = NSTask()
+
+        task.launchPath = "/bin/cat"
+        task.arguments = ["invalid_file_name"]
+
+        let errorPipe = NSPipe()
+        task.standardError = errorPipe
+
+        task.launch()
+        task.waitUntilExit()
+        XCTAssertEqual(task.terminationStatus, 1)
+
+        let data = errorPipe.fileHandleForReading.availableData
+        guard let string = String(data: data, encoding: NSASCIIStringEncoding) else {
+            XCTFail("Could not read stdout")
+            return
+        }
+        XCTAssertEqual(string, "cat: invalid_file_name: No such file or directory\n")
+    }
+
+    func test_file_stdout() {
+        let task = NSTask()
+
+        task.launchPath = "/usr/bin/which"
+        task.arguments = ["which"]
+
+        mkstemp(template: "TestNSTask.XXXXXX") { handle in
+            task.standardOutput = handle
+
+            task.launch()
+            task.waitUntilExit()
+            XCTAssertEqual(task.terminationStatus, 0)
+
+            handle.seekToFileOffset(0)
+            let data = handle.readDataToEndOfFile()
+            guard let string = String(data: data, encoding: NSASCIIStringEncoding) else {
+                XCTFail("Could not read stdout")
+                return
+            }
+            XCTAssertEqual(string, "/usr/bin/which\n")
+        }
+    }
 }
+
+private func mkstemp(template: String, body: @noescape (NSFileHandle) throws -> Void) rethrows {
+    let url = NSURL(fileURLWithPath: NSTemporaryDirectory()).URLByAppendingPathComponent("TestNSTask.XXXXXX")!
+    var buffer = [Int8](repeating: 0, count: Int(PATH_MAX))
+    url.getFileSystemRepresentation(&buffer, maxLength: buffer.count)
+    switch mkstemp(&buffer) {
+    case -1: XCTFail("Could not create temporary file")
+    case let fd:
+        defer { unlink(&buffer) }
+        try body(NSFileHandle(fileDescriptor: fd, closeOnDealloc: true))
+    }
+}

TestFoundation/main.swift

@@ -58,8 +58,8 @@ XCTMain([
     testCase(TestNSScanner.allTests),
     testCase(TestNSSet.allTests),
     testCase(TestNSString.allTests),
-//    testCase(TestNSTask.allTests),
 //    testCase(TestNSThread.allTests),
+    testCase(TestNSTask.allTests),
     testCase(TestNSTimer.allTests),
     testCase(TestNSTimeZone.allTests),
     testCase(TestNSURL.allTests),
@@ -75,4 +75,5 @@ XCTMain([
     testCase(TestNSXMLParser.allTests),
     testCase(TestNSXMLDocument.allTests),
     testCase(TestNSAttributedString.allTests),
+    testCase(TestNSFileHandle.allTests),
 ])