Refactor RST_STREAM status code handling.

net/spdy/spdy_protocol.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains some protocol structures for use with SPDY 2 and 3
 // The SPDY 2 spec can be found at:
 // http://dev.chromium.org/spdy/spdy-protocol/spdy-protocol-draft2
 // The SPDY 3 spec can be found at:
 // http://dev.chromium.org/spdy/spdy-protocol/spdy-protocol-draft3
 
@@ skipping 342 matching lines @@
   SETTINGS_HEADER_TABLE_SIZE = 0x8,
   // Whether or not server push (PUSH_PROMISE) is enabled.
   SETTINGS_ENABLE_PUSH = 0x9,
 };
 
 // Status codes for RST_STREAM frames.
 enum SpdyRstStreamStatus {
   RST_STREAM_INVALID = 0,
   RST_STREAM_PROTOCOL_ERROR = 1,
   RST_STREAM_INVALID_STREAM = 2,
+  RST_STREAM_STREAM_CLOSED = 2,  // Equivalent to INVALID_STREAM
   RST_STREAM_REFUSED_STREAM = 3,
   RST_STREAM_UNSUPPORTED_VERSION = 4,
   RST_STREAM_CANCEL = 5,
   RST_STREAM_INTERNAL_ERROR = 6,
   RST_STREAM_FLOW_CONTROL_ERROR = 7,
   RST_STREAM_STREAM_IN_USE = 8,
   RST_STREAM_STREAM_ALREADY_CLOSED = 9,
   RST_STREAM_INVALID_CREDENTIALS = 10,
   RST_STREAM_FRAME_TOO_LARGE = 11,
-  RST_STREAM_NUM_STATUS_CODES = 12
+  RST_STREAM_FRAME_SIZE_ERROR = 11,  // Equivalent to FRAME_TOO_LARGE

[jar (doing other things), 2014/04/22 00:02:59]

nit: If you're not going to distigiush them... why not just use FRAME_SIZE_ERROR
everywhere, and get rid of TOO_LARGE?

[Johnny, 2014/04/22 00:31:27]

Yea, this is not optimal, but: FRAME_TOO_LARGE is a specific error name in the
SPDY/3.1 specification. FRAME_SIZE_ERROR is a specific error name in the HTTP/2
specification.

We're supporting both specifications with this codebase; their meanings are so
semantically close that Hasan elected to map them to the same internal error in
this CL.

[jar (doing other things), 2014/04/25 16:03:45]

OK... good enough.  Might be worth a comment... but your choice.

+  RST_STREAM_SETTINGS_TIMEOUT = 12,
+  RST_STREAM_CONNECT_ERROR = 13,
+  RST_STREAM_ENHANCE_YOUR_CALM = 14,
+  RST_STREAM_NUM_STATUS_CODES = 15
 };
 
 // Status codes for GOAWAY frames.
 enum SpdyGoAwayStatus {
   GOAWAY_INVALID = -1,
   GOAWAY_OK = 0,
   GOAWAY_PROTOCOL_ERROR = 1,
   GOAWAY_INTERNAL_ERROR = 2,
   GOAWAY_NUM_STATUS_CODES = 3  // Must be last.
 };
@@ skipping 36 matching lines @@
   // version.
   // Behavior is undefined for invalid setting id fields; consumers should first
   // use IsValidSettingId() to verify validity of setting id fields.
   static SpdySettingsIds ParseSettingId(SpdyMajorVersion version,
                                         int setting_id_field);
 
   // Serializes a given setting id to the on-the-wire enumeration value for the
   // given protocol version.
   // Returns -1 on failure (I.E. Invalid setting id for the given version).
   static int SerializeSettingId(SpdyMajorVersion version, SpdySettingsIds id);
+
+  // Returns true if a given on-the-wire enumeration of a RST_STREAM status code
+  // is valid for a given protocol version, false otherwise.
+  static bool IsValidRstStreamStatus(SpdyMajorVersion version,
+                                     int rst_stream_status_field);
+
+  // Parses a RST_STREAM status code from an on-the-wire enumeration of a given
+  // protocol version.
+  // Behavior is undefined for invalid RST_STREAM status code fields; consumers
+  // should first use IsValidRstStreamStatus() to verify validity of RST_STREAM
+  // status code fields..
+  static SpdyRstStreamStatus ParseRstStreamStatus(SpdyMajorVersion version,
+                                                  int rst_stream_status_field);
+
+  // Serializes a given RST_STREAM status code to the on-the-wire enumeration
+  // value for the given protocol version.
+  // Returns -1 on failure (I.E. Invalid RST_STREAM status code for the given
+  // version).
+  static int SerializeRstStreamStatus(SpdyMajorVersion version,
+                                      SpdyRstStreamStatus rst_stream_status);
 };
 
 class SpdyFrame;
 typedef SpdyFrame SpdySerializedFrame;
 
 class SpdyFrameVisitor;
 
 // Intermediate representation for SPDY frames.
 // TODO(hkhalil): Rename this class to SpdyFrame when the existing SpdyFrame is
 // gone.
@@ skipping 190 matching lines @@
  public:
   SpdyRstStreamIR(SpdyStreamId stream_id, SpdyRstStreamStatus status,
                   base::StringPiece description);
 
   virtual ~SpdyRstStreamIR();
 
   SpdyRstStreamStatus status() const {
     return status_;
   }
   void set_status(SpdyRstStreamStatus status) {
-    DCHECK_NE(status, RST_STREAM_INVALID);
-    DCHECK_LT(status, RST_STREAM_NUM_STATUS_CODES);
     status_ = status;
   }
 
   base::StringPiece description() const { return description_; }
 
   void set_description(base::StringPiece description) {
     description_ = description;
   }
 
   virtual void Visit(SpdyFrameVisitor* visitor) const OVERRIDE;
@@ skipping 264 matching lines @@
   SpdyFrameVisitor() {}
   virtual ~SpdyFrameVisitor() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SpdyFrameVisitor);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_PROTOCOL_H_