Change the WebSocket OpCode constants to an enum

net/websockets/websocket_frame.h

Index: net/websockets/websocket_frame.h
diff --git a/net/websockets/websocket_frame.h b/net/websockets/websocket_frame.h
index ff146768f8d1358ba38eaaff839020a1cd8ab95e..37bf6f758f69eb07c9f287e270217401c4ce7e2d 100644
--- a/net/websockets/websocket_frame.h
+++ b/net/websockets/websocket_frame.h
@@ -22,25 +22,32 @@ class IOBufferWithSize;
 // (see http://tools.ietf.org/html/rfc6455#section-5.2).
 struct NET_EXPORT WebSocketFrameHeader {
   typedef int OpCode;
-  static const OpCode kOpCodeContinuation;
-  static const OpCode kOpCodeText;
-  static const OpCode kOpCodeBinary;
-  static const OpCode kOpCodeDataUnused;
-  static const OpCode kOpCodeClose;
-  static const OpCode kOpCodePing;
-  static const OpCode kOpCodePong;
-  static const OpCode kOpCodeControlUnused;
+
+  // Originally these constants were static const int, but to make it possible
+  // to use them in a switch statement they were changed to an enum.
+  enum OpCodeEnum {
+    kOpCodeContinuation = 0x0,
+    kOpCodeText = 0x1,
+    kOpCodeBinary = 0x2,
+    kOpCodeDataUnused = 0x3,
+    kOpCodeClose = 0x8,
+    kOpCodePing = 0x9,
+    kOpCodePong = 0xA,
+    kOpCodeControlUnused = 0xB,
+  };
 
   // Efficiently determine whether a given opcode is one of the data opcodes

[yhirano, 2013/05/20 05:06:02]

Does "Efficiently" means using the bit operation? Then we should modify this
comment, I think.

[Adam Rice, 2013/05/20 07:19:49]

Originally I wrote "efficiently" to constrast against comparing the values
directly, which was inefficient to users of this header because the values
weren't available at compile time. 

Now that the values are in the header it doesn't make any difference to
efficiency, it is just useful to have a single function to give the answer.

So I have removed the word "Efficiently".

   // known to this implementation.
-  static bool IsKnownDataOpCode(OpCode opCode) {
-    return (opCode & ~3) == 0 && opCode != 3;
+  static bool IsKnownDataOpCode(OpCode opcode) {
+    return opcode == kOpCodeContinuation || opcode == kOpCodeText ||
+           opcode == kOpCodeBinary;
   }
 
   // Efficiently determine whether a given opcode is one of the control opcodes

[yhirano, 2013/05/20 05:06:02]

Ditto

[Adam Rice, 2013/05/20 07:19:49]

Done.

   // known to this implementation.
-  static bool IsKnownControlOpCode(OpCode opCode) {
-    return (opCode & ~3) == 8 && opCode != 0x0B;
+  static bool IsKnownControlOpCode(OpCode opcode) {
+    return opcode == kOpCodeClose || opcode == kOpCodePing ||
+           opcode == kOpCodePong;
   }
 
   // These values must be a compile-time constant. "enum hack" is used here
@@ -53,13 +60,13 @@ struct NET_EXPORT WebSocketFrameHeader {
 
   // Constructor to avoid a lot of repetitive initialisation.
   explicit WebSocketFrameHeader(OpCode opCode)
-    : final(false),
-      reserved1(false),
-      reserved2(false),
-      reserved3(false),
-      opcode(opCode),
-      masked(false),
-      payload_length(0) {}
+      : final(false),
+        reserved1(false),
+        reserved2(false),
+        reserved3(false),
+        opcode(opCode),
+        masked(false),
+        payload_length(0) {}
 
   // Create a clone of this object on the heap.
   scoped_ptr<WebSocketFrameHeader> Clone();
@@ -119,8 +126,7 @@ struct WebSocketMaskingKey {
 // Returns the size of WebSocket frame header. The size of WebSocket frame
 // header varies from 2 bytes to 14 bytes depending on the payload length
 // and maskedness.
-NET_EXPORT int GetWebSocketFrameHeaderSize(
-    const WebSocketFrameHeader& header);
+NET_EXPORT int GetWebSocketFrameHeaderSize(const WebSocketFrameHeader& header);
 
 // Writes wire format of a WebSocket frame header into |output|, and returns
 // the number of bytes written.
@@ -138,11 +144,10 @@ NET_EXPORT int GetWebSocketFrameHeaderSize(
 // GetWebSocketFrameHeaderSize() can be used to know the size of header
 // beforehand. If the size of |buffer| is insufficient, this function returns
 // ERR_INVALID_ARGUMENT and does not write any data to |buffer|.
-NET_EXPORT int WriteWebSocketFrameHeader(
-    const WebSocketFrameHeader& header,
-    const WebSocketMaskingKey* masking_key,
-    char* buffer,
-    int buffer_size);
+NET_EXPORT int WriteWebSocketFrameHeader(const WebSocketFrameHeader& header,
+                                         const WebSocketMaskingKey* masking_key,
+                                         char* buffer,
+                                         int buffer_size);
 
 // Generates a masking key suitable for use in a new WebSocket frame.
 NET_EXPORT WebSocketMaskingKey GenerateWebSocketMaskingKey();