Add new HTTP/2 and HPACK decoder in net/http2/.

net/http2/decoder/payload_decoders/data_payload_decoder.cc

Index: net/http2/decoder/payload_decoders/data_payload_decoder.cc
diff --git a/net/http2/decoder/payload_decoders/data_payload_decoder.cc b/net/http2/decoder/payload_decoders/data_payload_decoder.cc
new file mode 100644
index 0000000000000000000000000000000000000000..60b8a714f1996f31755c0c0db548e8aa1fe0c274
--- /dev/null
+++ b/net/http2/decoder/payload_decoders/data_payload_decoder.cc
@@ -0,0 +1,123 @@
+// Copyright 2016 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.
+
+#include "net/http2/decoder/payload_decoders/data_payload_decoder.h"
+
+#include <stddef.h>
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "net/http2/decoder/decode_buffer.h"
+#include "net/http2/decoder/http2_frame_decoder_listener.h"
+#include "net/http2/http2_constants.h"
+#include "net/http2/http2_structures.h"
+#include "net/http2/tools/http2_bug_tracker.h"
+
+namespace net {
+
+std::ostream& operator<<(std::ostream& out,
+                         DataPayloadDecoder::PayloadState v) {
+  switch (v) {
+    case DataPayloadDecoder::PayloadState::kReadPadLength:
+      return out << "kReadPadLength";
+    case DataPayloadDecoder::PayloadState::kReadPayload:
+      return out << "kReadPayload";
+    case DataPayloadDecoder::PayloadState::kSkipPadding:
+      return out << "kSkipPadding";
+  }
+  return out << static_cast<int>(v);
+}
+
+DecodeStatus DataPayloadDecoder::StartDecodingPayload(FrameDecoderState* state,
+                                                      DecodeBuffer* db) {
+  const Http2FrameHeader& frame_header = state->frame_header();
+  const uint32_t total_length = frame_header.payload_length;
+
+  DVLOG(2) << "DataPayloadDecoder::StartDecodingPayload: " << frame_header;
+  DCHECK_EQ(Http2FrameType::DATA, frame_header.type);
+  DCHECK_LE(db->Remaining(), total_length);
+  DCHECK_EQ(
+      0, frame_header.flags &
+             ~(Http2FrameFlag::FLAG_END_STREAM | Http2FrameFlag::FLAG_PADDED));
+
+  // Special case for the hoped for common case: unpadded and fits fully into
+  // the decode buffer. TO BE SEEN if that is true. It certainly requires that
+  // the transport buffers be large (e.g. >> 16KB typically).
+  // TODO(jamessynge) Add counters.
+  DVLOG(2) << "StartDecodingPayload total_length=" << total_length;
+  if (!frame_header.IsPadded()) {
+    DVLOG(2) << "StartDecodingPayload !IsPadded";
+    if (db->Remaining() == total_length) {
+      DVLOG(2) << "StartDecodingPayload all present";
+      // Note that we don't cache the listener field so that the callee can
+      // replace it if the frame is bad.
+      // If this case is common enough, consider combining the 3 callbacks
+      // into one.
+      state->listener()->OnDataStart(frame_header);
+      if (total_length > 0) {
+        state->listener()->OnDataPayload(db->cursor(), total_length);
+        db->AdvanceCursor(total_length);
+      }
+      state->listener()->OnDataEnd();
+      return DecodeStatus::kDecodeDone;
+    }
+    payload_state_ = PayloadState::kReadPayload;
+  } else {
+    payload_state_ = PayloadState::kReadPadLength;
+  }
+  state->InitializeRemainders();
+  state->listener()->OnDataStart(frame_header);
+  return ResumeDecodingPayload(state, db);
+}
+
+DecodeStatus DataPayloadDecoder::ResumeDecodingPayload(FrameDecoderState* state,
+                                                       DecodeBuffer* db) {
+  DVLOG(2) << "DataPayloadDecoder::ResumeDecodingPayload payload_state_="
+           << payload_state_;
+  const Http2FrameHeader& frame_header = state->frame_header();
+  DCHECK_EQ(Http2FrameType::DATA, frame_header.type);
+  DCHECK_LE(state->remaining_payload_and_padding(),
+            frame_header.payload_length);
+  DCHECK_LE(db->Remaining(), state->remaining_payload_and_padding());
+  DecodeStatus status;
+  size_t avail;
+  switch (payload_state_) {
+    case PayloadState::kReadPadLength:
+      // ReadPadLength handles the OnPadLength callback, and updating the
+      // remaining_payload and remaining_padding fields. If the amount of
+      // padding is too large to fit in the frame's payload, ReadPadLength
+      // instead calls OnPaddingTooLong and returns kDecodeError.
+      status = state->ReadPadLength(db, /*report_pad_length*/ true);
+      if (status != DecodeStatus::kDecodeDone) {
+        return status;
+      }
+    // FALLTHROUGH_INTENDED
+
+    case PayloadState::kReadPayload:
+      avail = state->AvailablePayload(db);
+      if (avail > 0) {
+        state->listener()->OnDataPayload(db->cursor(), avail);
+        db->AdvanceCursor(avail);
+        state->ConsumePayload(avail);
+      }
+      if (state->remaining_payload() > 0) {
+        payload_state_ = PayloadState::kReadPayload;
+        return DecodeStatus::kDecodeInProgress;
+      }
+    // FALLTHROUGH_INTENDED
+
+    case PayloadState::kSkipPadding:
+      // SkipPadding handles the OnPadding callback.
+      if (state->SkipPadding(db)) {
+        state->listener()->OnDataEnd();
+        return DecodeStatus::kDecodeDone;
+      }
+      payload_state_ = PayloadState::kSkipPadding;
+      return DecodeStatus::kDecodeInProgress;
+  }
+  HTTP2_BUG << "PayloadState: " << payload_state_;
+  return DecodeStatus::kDecodeError;
+}
+
+}  // namespace net