From 981076d393f462e1b72ed75b1d67505c254edcc9 Mon Sep 17 00:00:00 2001
From: Alsey Coleman Miller <alseycmiller@gmail.com>
Date: Tue, 11 Sep 2018 22:04:52 -0500
Subject: [PATCH] Working on non-blocking reading

---
 Sources/BluetoothLinux/L2CAP.swift            | 31 ++++++++++++++++---
 .../CSwiftBluetoothLinux/include/bluetooth.h  |  1 +
 2 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/Sources/BluetoothLinux/L2CAP.swift b/Sources/BluetoothLinux/L2CAP.swift
index b225a13..15dbde5 100644
--- a/Sources/BluetoothLinux/L2CAP.swift
+++ b/Sources/BluetoothLinux/L2CAP.swift
@@ -229,9 +229,14 @@ public final class L2CAPSocket: L2CAPSocketProtocol {
         // error accepting new connection
         guard client >= 0 else { throw POSIXError.fromErrno! }
 
-        return L2CAPSocket(clientSocket: client,
-                           remoteAddress: remoteAddress,
-                           securityLevel: securityLevel)
+        let newSocket = L2CAPSocket(clientSocket: client,
+                                    remoteAddress: remoteAddress,
+                                    securityLevel: securityLevel)
+        
+        // make socket non-blocking
+        try newSocket.setNonblocking()
+        
+        return newSocket
     }
     
     /// Connect to another L2CAP server.
@@ -252,6 +257,9 @@ public final class L2CAPSocket: L2CAPSocketProtocol {
                 connect(internalSocket, $0, socklen_t(MemoryLayout<sockaddr_l2>.size)) == 0
             })
         }) else { throw POSIXError.fromErrno! }
+        
+        // make socket non-blocking
+        try setNonblocking()
     }
 
     /// Reads from the socket.
@@ -286,9 +294,22 @@ public final class L2CAPSocket: L2CAPSocketProtocol {
         guard fdCount != -1
             else { throw POSIXError.fromErrno! }
                 
-        return readSockets.contains(internalSocket)
+        return fdCount > 0
     }
-
+    
+    private func setNonblocking() throws {
+        
+        var flags = fcntl(internalSocket, F_GETFL, 0)
+        
+        guard flags != -1
+            else { throw POSIXError.fromErrno! }
+        
+        flags = fcntl(internalSocket, F_SETFL, flags | O_NONBLOCK);
+        
+        guard flags != -1
+            else { throw POSIXError.fromErrno! }
+    }
+    
     /// Write to the socket.
     public func send(_ data: Data) throws {
         
diff --git a/Sources/CSwiftBluetoothLinux/include/bluetooth.h b/Sources/CSwiftBluetoothLinux/include/bluetooth.h
index f946e68..5c4b9f7 100644
--- a/Sources/CSwiftBluetoothLinux/include/bluetooth.h
+++ b/Sources/CSwiftBluetoothLinux/include/bluetooth.h
@@ -83,3 +83,4 @@ __attribute__((swift_name("FileDescriptorSet.contains(self:_:)")))
 {
     return FD_ISSET(fileDescriptor, set);
 }
+