From f4eb86bae6460636cef1bb96c68515047ca67435 Mon Sep 17 00:00:00 2001
From: Johannes Weiss <johannesweiss@apple.com>
Date: Thu, 22 Aug 2019 19:44:11 +0100
Subject: [PATCH 1/3] do not inherit fds

---
 Foundation/Process.swift                | 18 ++++++++++++++++++
 TestFoundation/TestProcess.swift        | 20 ++++++++++++++++++++
 TestFoundation/xdgTestHelper/main.swift | 14 +++++++++++++-
 3 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/Foundation/Process.swift b/Foundation/Process.swift
index c89a244a92..1881cd5c89 100644
--- a/Foundation/Process.swift
+++ b/Foundation/Process.swift
@@ -8,6 +8,7 @@
 //
 
 import CoreFoundation
+import Darwin
 
 extension Process {
     public enum TerminationReason : Int {
@@ -837,6 +838,16 @@ open class Process: NSObject {
             posix(_CFPosixSpawnFileActionsAddClose(fileActions, fd))
         }
 
+        #if os(macOS)
+        var spawnAttrs: posix_spawnattr_t? = nil
+        posix_spawnattr_init(&spawnAttrs)
+        posix_spawnattr_setflags(&spawnAttrs, .init(POSIX_SPAWN_CLOEXEC_DEFAULT))
+        #else
+        for fd in 3..<getdtablesize() {
+            posix(_CFPosixSpawnFileActionsAddClose(fileActions, fd))
+        }
+        #endif
+
         let fileManager = FileManager()
         let previousDirectoryPath = fileManager.currentDirectoryPath
         if !fileManager.changeCurrentDirectoryPath(currentDirectoryURL.path) {
@@ -850,9 +861,16 @@ open class Process: NSObject {
 
         // Launch
         var pid = pid_t()
+        #if os(macOS)
+        guard _CFPosixSpawn(&pid, launchPath, fileActions, &spawnAttrs, argv, envp) == 0 else {
+            throw _NSErrorWithErrno(errno, reading: true, path: launchPath)
+        }
+        #else
         guard _CFPosixSpawn(&pid, launchPath, fileActions, nil, argv, envp) == 0 else {
             throw _NSErrorWithErrno(errno, reading: true, path: launchPath)
         }
+        #endif
+
 
         // Close the write end of the input and output pipes.
         if let pipe = standardInput as? Pipe {
diff --git a/TestFoundation/TestProcess.swift b/TestFoundation/TestProcess.swift
index 935a7c3735..f23371c511 100644
--- a/TestFoundation/TestProcess.swift
+++ b/TestFoundation/TestProcess.swift
@@ -565,6 +565,25 @@ class TestProcess : XCTestCase {
         XCTAssertEqual(String(data: stdoutData, encoding: .utf8)?.trimmingCharacters(in: .whitespacesAndNewlines), "No files specified.")
     }
 
+    func test_fileDescriptorsAreNotInherited() throws {
+        let task = Process()
+        let clonedFD = dup(1)
+        task.executableURL = xdgTestHelperURL()
+        task.arguments = ["--print-open-file-descriptors"]
+        task.standardInput = FileHandle.nullDevice
+        let stdoutPipe = Pipe()
+        task.standardOutput = stdoutPipe.fileHandleForWriting
+        task.standardError = FileHandle.nullDevice
+        XCTAssertNoThrow(try task.run())
+
+        try task.run()
+        try stdoutPipe.fileHandleForWriting.close()
+        let stdoutData = try stdoutPipe.fileHandleForReading.readToEnd()
+        task.waitUntilExit()
+        print(String(decoding: stdoutData ?? Data(), as: Unicode.UTF8.self))
+        XCTAssertEqual("0\n1\n2\n", String(decoding: stdoutData ?? Data(), as: Unicode.UTF8.self))
+        close(clonedFD)
+    }
 
     static var allTests: [(String, (TestProcess) -> () throws -> Void)] {
         var tests = [
@@ -592,6 +611,7 @@ class TestProcess : XCTestCase {
             ("test_redirect_all_using_null", test_redirect_all_using_null),
             ("test_redirect_all_using_nil", test_redirect_all_using_nil),
             ("test_plutil", test_plutil),
+            ("test_fileDescriptorsAreNotInherited", test_fileDescriptorsAreNotInherited),
         ]
 
 #if !os(Windows)
diff --git a/TestFoundation/xdgTestHelper/main.swift b/TestFoundation/xdgTestHelper/main.swift
index 1950db2750..c010892d83 100644
--- a/TestFoundation/xdgTestHelper/main.swift
+++ b/TestFoundation/xdgTestHelper/main.swift
@@ -206,6 +206,15 @@ func cat(_ args: ArraySlice<String>.Iterator) {
     exit(exitCode)
 }
 
+func printOpenFileDescriptors() {
+    for fd in 0..<getdtablesize() {
+        if fcntl(fd, F_GETFD) != -1 {
+            print(fd)
+        }
+    }
+    exit(0)
+}
+
 // -----
 
 var arguments = ProcessInfo.processInfo.arguments.dropFirst().makeIterator()
@@ -265,7 +274,10 @@ case "--nspathfor":
 case "--signal-test":
     signalTest()
 #endif
-    
+
+case "--print-open-file-descriptors":
+    printOpenFileDescriptors()
+
 default:
     fatalError("These arguments are not recognized. Only run this from a unit test.")
 }

From eb23f1e9b0e5ff149ad7e04855791f02353b7889 Mon Sep 17 00:00:00 2001
From: Lily Vulcano <millenomi@apple.com>
Date: Thu, 22 Aug 2019 14:04:23 -0700
Subject: [PATCH 2/3] Cleanup:  - POSIX_SPAWN_CLOEXEC_DEFAULT is a constant
 offered by the Darwin module. Import it conditionally that way.  - Do not
 close Pipe/FileHandle-owned fds.

---
 Foundation/Process.swift | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/Foundation/Process.swift b/Foundation/Process.swift
index 1881cd5c89..6dd06f1079 100644
--- a/Foundation/Process.swift
+++ b/Foundation/Process.swift
@@ -8,7 +8,10 @@
 //
 
 import CoreFoundation
+
+#if canImport(Darwin)
 import Darwin
+#endif
 
 extension Process {
     public enum TerminationReason : Int {
@@ -838,12 +841,16 @@ open class Process: NSObject {
             posix(_CFPosixSpawnFileActionsAddClose(fileActions, fd))
         }
 
-        #if os(macOS)
+        #if canImport(Darwin)
         var spawnAttrs: posix_spawnattr_t? = nil
         posix_spawnattr_init(&spawnAttrs)
         posix_spawnattr_setflags(&spawnAttrs, .init(POSIX_SPAWN_CLOEXEC_DEFAULT))
         #else
-        for fd in 3..<getdtablesize() {
+        for fd in 3 ..< getdtablesize() {
+            guard adddup2[fd] == nil &&
+                  !addclose.contains(fd) else {
+                    continue // Do not double-close descriptors, or close those pertaining to Pipes or FileHandles we want inherited.
+            }
             posix(_CFPosixSpawnFileActionsAddClose(fileActions, fd))
         }
         #endif

From c6da1a0151b4aaf94c8287add85c1ddf9fddef42 Mon Sep 17 00:00:00 2001
From: Johannes Weiss <johannesweiss@apple.com>
Date: Fri, 30 Aug 2019 15:21:12 +0100
Subject: [PATCH 3/3] more cleanup

---
 Foundation/Process.swift                |  3 ++-
 TestFoundation/TestProcess.swift        | 19 +++++++++++++------
 TestFoundation/xdgTestHelper/main.swift |  4 +++-
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/Foundation/Process.swift b/Foundation/Process.swift
index 6dd06f1079..6c0e30e1ce 100644
--- a/Foundation/Process.swift
+++ b/Foundation/Process.swift
@@ -848,7 +848,8 @@ open class Process: NSObject {
         #else
         for fd in 3 ..< getdtablesize() {
             guard adddup2[fd] == nil &&
-                  !addclose.contains(fd) else {
+                  !addclose.contains(fd) &&
+                  fd != taskSocketPair[1] else {
                     continue // Do not double-close descriptors, or close those pertaining to Pipes or FileHandles we want inherited.
             }
             posix(_CFPosixSpawnFileActionsAddClose(fileActions, fd))
diff --git a/TestFoundation/TestProcess.swift b/TestFoundation/TestProcess.swift
index f23371c511..3f6ccae85a 100644
--- a/TestFoundation/TestProcess.swift
+++ b/TestFoundation/TestProcess.swift
@@ -567,7 +567,7 @@ class TestProcess : XCTestCase {
 
     func test_fileDescriptorsAreNotInherited() throws {
         let task = Process()
-        let clonedFD = dup(1)
+        let someExtraFDs = [dup(1), dup(1), dup(1), dup(1), dup(1), dup(1), dup(1)]
         task.executableURL = xdgTestHelperURL()
         task.arguments = ["--print-open-file-descriptors"]
         task.standardInput = FileHandle.nullDevice
@@ -576,13 +576,20 @@ class TestProcess : XCTestCase {
         task.standardError = FileHandle.nullDevice
         XCTAssertNoThrow(try task.run())
 
-        try task.run()
         try stdoutPipe.fileHandleForWriting.close()
         let stdoutData = try stdoutPipe.fileHandleForReading.readToEnd()
         task.waitUntilExit()
-        print(String(decoding: stdoutData ?? Data(), as: Unicode.UTF8.self))
-        XCTAssertEqual("0\n1\n2\n", String(decoding: stdoutData ?? Data(), as: Unicode.UTF8.self))
-        close(clonedFD)
+        let stdoutString = String(decoding: stdoutData ?? Data(), as: Unicode.UTF8.self)
+        #if os(macOS)
+        XCTAssertEqual("0\n1\n2\n", stdoutString)
+        #else
+        // on Linux we should also have a /dev/urandom open as well as some socket that Process uses for something.
+        XCTAssert(stdoutString.utf8.starts(with: "0\n1\n2\n3\n".utf8))
+        XCTAssertEqual(stdoutString.components(separatedBy: "\n").count, 6, "\(stdoutString)")
+        #endif
+        for fd in someExtraFDs {
+            close(fd)
+        }
     }
 
     static var allTests: [(String, (TestProcess) -> () throws -> Void)] {
@@ -611,7 +618,6 @@ class TestProcess : XCTestCase {
             ("test_redirect_all_using_null", test_redirect_all_using_null),
             ("test_redirect_all_using_nil", test_redirect_all_using_nil),
             ("test_plutil", test_plutil),
-            ("test_fileDescriptorsAreNotInherited", test_fileDescriptorsAreNotInherited),
         ]
 
 #if !os(Windows)
@@ -619,6 +625,7 @@ class TestProcess : XCTestCase {
         tests += [
             ("test_interrupt", test_interrupt),
             ("test_suspend_resume", test_suspend_resume),
+            ("test_fileDescriptorsAreNotInherited", test_fileDescriptorsAreNotInherited),
         ]
 #endif
         return tests
diff --git a/TestFoundation/xdgTestHelper/main.swift b/TestFoundation/xdgTestHelper/main.swift
index c010892d83..3f4e115ce3 100644
--- a/TestFoundation/xdgTestHelper/main.swift
+++ b/TestFoundation/xdgTestHelper/main.swift
@@ -206,6 +206,7 @@ func cat(_ args: ArraySlice<String>.Iterator) {
     exit(exitCode)
 }
 
+#if !os(Windows)
 func printOpenFileDescriptors() {
     for fd in 0..<getdtablesize() {
         if fcntl(fd, F_GETFD) != -1 {
@@ -214,6 +215,7 @@ func printOpenFileDescriptors() {
     }
     exit(0)
 }
+#endif
 
 // -----
 
@@ -273,10 +275,10 @@ case "--nspathfor":
 #if !os(Windows)
 case "--signal-test":
     signalTest()
-#endif
 
 case "--print-open-file-descriptors":
     printOpenFileDescriptors()
+#endif
 
 default:
     fatalError("These arguments are not recognized. Only run this from a unit test.")