Introduce new SpdyConstants class

net/spdy/spdy_protocol.cc

Index: net/spdy/spdy_protocol.cc
diff --git a/net/spdy/spdy_protocol.cc b/net/spdy/spdy_protocol.cc
index b9e458a8a83dd2f8d1beebd31ee551de196cf26e..a5f3a1c679198be225f1bb416f2b66937001f18f 100644
--- a/net/spdy/spdy_protocol.cc
+++ b/net/spdy/spdy_protocol.cc
@@ -27,6 +27,151 @@ SpdyDataIR::SpdyDataIR(SpdyStreamId stream_id)
 
 SpdyDataIR::~SpdyDataIR() {}
 
+bool SpdyConstants::IsValidFrameType(SpdyMajorVersion version,
+                                     int frame_type_field) {
+  switch (version) {
+    case SPDY2:
+    case SPDY3:
+      // SYN_STREAM is the first valid frame.
+      if (frame_type_field < SerializeFrameType(version, SYN_STREAM)) {
+        return false;
+      }
+
+      // WINDOW_UPDATE is the last valid frame.
+      if (frame_type_field > SerializeFrameType(version, WINDOW_UPDATE)) {
+        return false;
+      }
+
+      // The valid range is non-contiguous.
+      if (frame_type_field == NOOP) {
+        return false;
+      }
+
+      return true;
+    case SPDY4:
+      // DATA is the first valid frame.
+      if (frame_type_field < SerializeFrameType(version, DATA)) {
+        return false;
+      }
+
+      // BLOCKED is the last valid frame.
+      if (frame_type_field > SerializeFrameType(version, BLOCKED)) {
+        return false;
+      }
+
+      return true;
+  }
+}
+
+SpdyFrameType SpdyConstants::ParseFrameType(SpdyMajorVersion version,
+                                            int frame_type_field) {
+  switch (version) {
+    case SPDY2:
+    case SPDY3:
+      switch (frame_type_field) {
+        case 1:
+          return SYN_STREAM;
+        case 2:
+          return SYN_REPLY;
+        case 3:
+          return RST_STREAM;
+        case 4:
+          return SETTINGS;
+        case 6:
+          return PING;
+        case 7:
+          return GOAWAY;
+        case 8:
+          return HEADERS;
+        case 9:
+          return WINDOW_UPDATE;
+        default:
+          return DATA;
+      }
+    case SPDY4:
+      switch (frame_type_field) {
+        case 0:
+          return DATA;
+        case 1:
+          return HEADERS;
+        // TODO(hkhalil): Add PRIORITY.
+        case 3:
+          return RST_STREAM;
+        case 4:
+          return SETTINGS;
+        case 5:
+          return PUSH_PROMISE;
+        case 6:
+          return PING;
+        case 7:
+          return GOAWAY;
+        case 8:
+          return WINDOW_UPDATE;
+        case 9:
+          return CONTINUATION;
+        case 10:
+          return BLOCKED;
+        default:
+          return DATA;
+      }
+  }
+  return DATA;
+}
+
+int SpdyConstants::SerializeFrameType(SpdyMajorVersion version,
+                                      SpdyFrameType frame_type) {
+  switch (version) {
+    case SPDY2:
+    case SPDY3:
+      switch (frame_type) {
+        case SYN_STREAM:
+          return 1;
+        case SYN_REPLY:
+          return 2;
+        case RST_STREAM:
+          return 3;
+        case SETTINGS:
+          return 4;
+        case PING:
+          return 6;
+        case GOAWAY:
+          return 7;
+        case HEADERS:
+          return 8;
+        case WINDOW_UPDATE:
+          return 9;
+        default:
+          return -1;
+      }
+    case SPDY4:
+      switch (frame_type) {
+        case DATA:
+          return 0;
+        case HEADERS:
+          return 1;
+        // TODO(hkhalil): Add PRIORITY.
+        case RST_STREAM:
+          return 3;
+        case SETTINGS:
+          return 4;
+        case PUSH_PROMISE:
+          return 5;
+        case PING:
+          return 6;
+        case GOAWAY:
+          return 7;
+        case WINDOW_UPDATE:
+          return 8;
+        case CONTINUATION:
+          return 9;
+        case BLOCKED:
+          return 10;
+        default:
+          return -1;
+      }
+  }
+}
+
 void SpdyDataIR::Visit(SpdyFrameVisitor* visitor) const {
   return visitor->VisitData(*this);
 }