Changed SOCKET_DEFAULT_MAX_CONNECTIONS to SOCKET_DEFAULT_MAX_BACKLOG and changed the default from 5 to 50. Added SOCKET_MAX_DARWIN_BACKLOG for macOS. Changed the signature of listen(on port: Int, maxPendingConnections: Int) to listen(on port: Int, maxBacklogSize: Int = Socket.SOCKET_DEFAULT_MAX_BACKLOG) and removed the listen(on port: Int) API since the same can be accomplished using defaults. Updated documentation in README.md to reflect changes.

Author: Bill Abt

README.md

@@ -1,7 +1,7 @@
 # BlueSocket
 
 ## Overview
-Socket framework for Swift using the Swift Package Manager. Works on OS X and Linux.
+Socket framework for Swift using the Swift Package Manager. Works on macOS and Linux.
 
 ## Contents
 
@@ -12,9 +12,9 @@ Socket framework for Swift using the Swift Package Manager. Works on OS X and Li
 ### Swift
 * Swift Open Source `swift-DEVELOPMENT-SNAPSHOT-2016-06-20-a` toolchain (**Minimum REQUIRED for latest release**)
 
-### OS X
+### macOS
 
-* OS X 10.11.0 (*El Capitan*) or higher
+* macOS 10.11.0 (*El Capitan*) or higher
 * Xcode Version 8.0 beta (8S128d) or higher using the above toolchain (*Recommended*)
 
 ### Linux
@@ -59,10 +59,9 @@ To close the socket of an open instance, the following function is provided:
 
 ### Listen on a socket.
 
-**BlueSocket** supports two ways to listen for an connection on a socket. These are:
-- `listen(on port: Int)`
-- `listen(on port: Int, maxPendingConnections: Int)`
-The first requires that you only specify a port upon which the socket will listen for connections. The second way allow you to limit the maximum number of incoming connection. In both cases, the function will determine the appropriate socket configuration based on the `port` specified.
+To use **BlueSocket** to listen for an connection on a socket the following API is provided:
+- `listen(on port: Int, maxBacklogSize: Int = Socket.SOCKET_DEFAULT_MAX_BACKLOG)`
+The first parameter `port`, is the port to be used to listen on. The second paramete, `maxBacklogSize` allows you to set the size of the queue holding pending connections. The function will determine the appropriate socket configuration based on the `port` specified.  For convenience on macOS, the constant `Socket.SOCKET_MAX_DARWIN_BACKLOG` can be set to use the maximum allowed backlog size.  The default value for all platforms is `Socket.SOCKET_DEFAULT_MAX_BACKLOG`, currently set to *5*.
 
 #### Example:
 

Sources/Socket.swift

@@ -20,12 +20,12 @@
 
 #if os(OSX) || os(iOS) || os(tvOS) || os(watchOS)
 	import Darwin
-	import Foundation
 #elseif os(Linux)
-	import Foundation
 	import Glibc
 #endif
 
+import Foundation
+
 // MARK: Socket
 
 ///
@@ -39,7 +39,10 @@ public class Socket: SocketReader, SocketWriter {
 
 	public static let SOCKET_MINIMUM_READ_BUFFER_SIZE		= 1024
 	public static let SOCKET_DEFAULT_READ_BUFFER_SIZE		= 4096
-	public static let SOCKET_DEFAULT_MAX_CONNECTIONS		= 5
+	public static let SOCKET_DEFAULT_MAX_BACKLOG			= 50
+	#if os(OSX)
+	public static let SOCKET_MAX_DARWIN_BACKLOG				= 128
+	#endif
 
 	public static let SOCKET_INVALID_PORT					= Int32(0)
 	public static let SOCKET_INVALID_DESCRIPTOR 			= Int32(-1)
@@ -582,10 +585,10 @@ public class Socket: SocketReader, SocketWriter {
 	}
 
 	///
-	/// Maximum number of pending connections per listening socket.
-	///		**Note:** Default value is `Socket.SOCKET_DEFAULT_MAX_CONNECTIONS`
+	/// Maximum size of the queue containing pending connections.
+	///		**Note:** Default value is `Socket.SOCKET_DEFAULT_MAX_BACKLOG`
 	///
-	public var maxPendingConnections: Int = Socket.SOCKET_DEFAULT_MAX_CONNECTIONS
+	public var maxBacklogSize: Int = Socket.SOCKET_DEFAULT_MAX_BACKLOG
 
 	///
 	/// True if this socket is connected. False otherwise. (Readonly)
@@ -1541,24 +1544,14 @@ public class Socket: SocketReader, SocketWriter {
 
 	// MARK: -- Listen
 
-	///
-	/// Listen on a port using the default for max pending connections.
-	///
-	/// - Parameter port: The port to listen on.
-	///
-	public func listen(on port: Int) throws {
-		
-		return try self.listen(on: port, maxPendingConnections: self.maxPendingConnections)
-	}
-	
 	///
 	/// Listen on a port, limiting the maximum number of pending connections.
 	///
 	/// - Parameters:
-	///		- port: 					The port to listen on.
-	/// 	- maxPendingConnections: 	The maximum number of pending connections to allow.
+	///		- port: 				The port to listen on.
+	/// 	- maxBacklogSize: 		The maximum size of the queue containing pending connections. Default is *Socket.SOCKET_DEFAULT_MAX_BACKLOG*.
 	///
-	public func listen(on port: Int, maxPendingConnections: Int) throws {
+	public func listen(on port: Int, maxBacklogSize: Int = Socket.SOCKET_DEFAULT_MAX_BACKLOG) throws {
 
 		// Set a flag so that this address can be re-used immediately after the connection
 		// closes.  (TCP normally imposes a delay before an address can be re-used.)
@@ -1568,10 +1561,10 @@ public class Socket: SocketReader, SocketWriter {
 			throw Error(code: Socket.SOCKET_ERR_SETSOCKOPT_FAILED, reason: self.lastError())
 		}
 
-		// Set the socket to ignore SIGPIPE to avoid dying on interrupted connections...
-		//	Note: Linux does not support the SO_NOSIGPIPE option. Instead, we use the
-		//		  MSG_NOSIGNAL flags passed to send.  See the writeData() functions below.
 		#if !os(Linux)
+			// Set the socket to ignore SIGPIPE to avoid dying on interrupted connections...
+			//	Note: Linux does not support the SO_NOSIGPIPE option. Instead, we use the
+			//		  MSG_NOSIGNAL flags passed to send.  See the writeData() functions below.
 			if setsockopt(self.socketfd, SOL_SOCKET, SO_NOSIGPIPE, &on, socklen_t(sizeof(Int32.self))) < 0 {
 
 				throw Error(code: Socket.SOCKET_ERR_SETSOCKOPT_FAILED, reason: self.lastError())
@@ -1705,12 +1698,12 @@ public class Socket: SocketReader, SocketWriter {
 
 		// Now listen for connections...
 		#if os(Linux)
-			if Glibc.listen(self.socketfd, Int32(maxPendingConnections)) < 0 {
+			if Glibc.listen(self.socketfd, Int32(maxBacklogSize)) < 0 {
 
 				throw Error(code: Socket.SOCKET_ERR_LISTEN_FAILED, reason: self.lastError())
 			}
 		#else
-			if Darwin.listen(self.socketfd, Int32(maxPendingConnections)) < 0 {
+			if Darwin.listen(self.socketfd, Int32(maxBacklogSize)) < 0 {
 
 				throw Error(code: Socket.SOCKET_ERR_LISTEN_FAILED, reason: self.lastError())
 			}