fix clean up memory in log task executor

Source/Swiftline/CommandExecutor.swift

@@ -96,27 +96,28 @@ class LogTaskExecutor: TaskExecutor {
 
     func execute(_ commandParts: [String]) -> ExecutorReturnValue  {
         let argv: [UnsafeMutablePointer<CChar>?] = commandParts.map{ $0.withCString(strdup) }
-        defer { for case let arg? in argv { free(arg) } }
-
         var pid: pid_t = 0
         var childFDActions: posix_spawn_file_actions_t? = nil
         let outputPipe: Int32 = 69
         let outerrPipe: Int32 = 70
 
+        defer {
+            for case let arg? in argv { free(arg) }
+            posix_spawn_file_actions_addclose(&childFDActions, outputPipe)
+            posix_spawn_file_actions_addclose(&childFDActions, outerrPipe)
+            posix_spawn_file_actions_destroy(&childFDActions)
+        }
+
         posix_spawn_file_actions_init(&childFDActions)
         posix_spawn_file_actions_addopen(&childFDActions, outputPipe, stdoutLogPath, O_CREAT | O_TRUNC | O_WRONLY, ~0)
         posix_spawn_file_actions_addopen(&childFDActions, outerrPipe, stderrLogPath, O_CREAT | O_TRUNC | O_WRONLY, ~0)
         posix_spawn_file_actions_adddup2(&childFDActions, outputPipe, 1)
         posix_spawn_file_actions_adddup2(&childFDActions, outerrPipe, 2)
 
         var result = posix_spawn(&pid, argv[0], &childFDActions, nil, argv + [nil], nil)
-        guard result == 0 else { return (Int(1), "", "") }
-
+        guard result == 0 else { return (Int(result), "", "") }
         waitpid(pid, &result, 0)
-        posix_spawn_file_actions_addclose(&childFDActions, outputPipe)
-        posix_spawn_file_actions_addclose(&childFDActions, outerrPipe)
-        posix_spawn_file_actions_destroy(&childFDActions)
-
+
         let (stdout, stderr) = read(outputPath: stdoutLogPath, outerrPath: stderrLogPath)
         removeFiles(stdoutLogPath, stderrLogPath)
         write(atPath: logPath, content: "\(stdout)\n\(stderr)")