Bug/BLE packet parsing

lib/adaptors/ble.js

@@ -165,7 +165,7 @@ Adaptor.prototype.devModeOn = function(callback) {
                                function(e, c) {
           if (e) { return callback(e); }
           c.on("read", function(data) {
-            if (data && data.length > 5) {
+            if (data) {
               self.readHandler(data);
             }
           });

lib/packet.js

@@ -68,33 +68,77 @@ Packet.prototype.create = function(opts) {
   return packet;
 };
 
+Packet.prototype._checkIfValid = function(buffer) {
+
+  if (this._checkMinSize(buffer)) {
+    // Packet is at least 6 bytes long
+
+    if (this._checkSOPs(buffer)) {
+      // Packet has valid header
+
+      if (this._checkExpectedSize(buffer) > -1) {
+        // If the buffer is at least of length
+        // specified in the DLEN value the buffer
+        // is valid (deal with extra bytes later)
+        return true;
+      }
+    }
+  }
+
+  return false;
+};
+
+Packet.prototype._checkIfInvalid = function(buffer) {
+
+  if (buffer.length >= 2) {
+
+    if (!this._checkSOPs(buffer)) {
+      // Discard packet of minimal size,
+      // but without a valid header
+      return true;
+    }
+  }
+
+  return false;
+
+};
+
 Packet.prototype.parse = function(buffer) {
+
+  if (this._checkIfValid(buffer)) {
+    // HACK: prevent having two valid packets
+    // in buffer and only react on the most recent one
+    // If received buffer is valid, compute
+    // it and drop all previous
+    this.partialBuffer = new Buffer(0);
+    return this._parse(buffer);
+  }
+
   if (this.partialBuffer.length > 0) {
+    // Concatenate with previous fragment
     buffer = Buffer.concat(
       [this.partialBuffer, buffer],
-      buffer.length + this.partialBuffer.length
+      this.partialBuffer.length + buffer.length
     );
+  }
 
+  if (this._checkIfInvalid(buffer)) {
+    // Drop if concatenation or received
+    // fragment is clearly invalid
     this.partialBuffer = new Buffer(0);
-  } else {
-    this.partialBuffer = new Buffer(buffer);
+    return null;
   }
 
-  if (this._checkSOPs(buffer)) {
-    // Check the packet is at least 6 bytes long
-    if (this._checkMinSize(buffer)) {
-      // Check the buffer length matches the
-      // DLEN value specified in the buffer
-      if (this._checkExpectedSize(buffer) > -1) {
-        // If the packet looks good parse it
-        return this._parse(buffer);
-      }
-    }
-
-    this.partialBuffer = new Buffer(buffer);
+  if (this._checkIfValid(buffer)) {
+    // Parse if valid, take care of
+    // extra bytes within
+    return this._parse(buffer);
   }
 
+  // Transfer too small packets to next step
+  this.partialBuffer = new Buffer(buffer);
   return null;
+
 };
 
 Packet.prototype._parse = function(buffer) {