net/spdy/spdy_buffer.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/spdy/spdy_buffer.h"
   6
   7 #include <cstring>
   8
   9 #include "base/callback.h"
  10 #include "base/logging.h"
  11 #include "base/profiler/scoped_tracker.h"
  12 #include "net/base/io_buffer.h"
  13 #include "net/spdy/spdy_protocol.h"
  14
  15 namespace net {
  16
  17 namespace {
  18
  19 // Bound on largest frame any SPDY version has allowed.
  20 const size_t kMaxSpdyFrameSize = 0x00ffffff;
  21
  22 // Makes a SpdyFrame with |size| bytes of data copied from
  23 // |data|. |data| must be non-NULL and |size| must be positive.
  24 scoped_ptr<SpdyFrame> MakeSpdyFrame(const char* data, size_t size) {
  25   DCHECK(data);
  26   CHECK_GT(size, 0u);
  27   CHECK_LE(size, kMaxSpdyFrameSize);
  28   scoped_ptr<char[]> frame_data(new char[size]);
  29   std::memcpy(frame_data.get(), data, size);
  30   scoped_ptr<SpdyFrame> frame(
  31       new SpdyFrame(frame_data.release(), size, true /* owns_buffer */));
  32   return frame.Pass();
  33 }
  34
  35 }  // namespace
  36
  37 // This class is an IOBuffer implementation that simply holds a
  38 // reference to a SharedFrame object and a fixed offset. Used by
  39 // SpdyBuffer::GetIOBufferForRemainingData().
  40 class SpdyBuffer::SharedFrameIOBuffer : public IOBuffer {
  41  public:
  42   SharedFrameIOBuffer(const scoped_refptr<SharedFrame>& shared_frame,
  43                       size_t offset)
  44       : IOBuffer(shared_frame->data->data() + offset),
  45         shared_frame_(shared_frame) {}
  46
  47  private:
  48   ~SharedFrameIOBuffer() override {
  49     // Prevent ~IOBuffer() from trying to delete |data_|.
  50     data_ = NULL;
  51   }
  52
  53   const scoped_refptr<SharedFrame> shared_frame_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(SharedFrameIOBuffer);
  56 };
  57
  58 SpdyBuffer::SpdyBuffer(scoped_ptr<SpdyFrame> frame)
  59     : shared_frame_(new SharedFrame()),
  60       offset_(0) {
  61   shared_frame_->data = frame.Pass();
  62 }
  63
  64 // The given data may not be strictly a SPDY frame; we (ab)use
  65 // |frame_| just as a container.
  66 SpdyBuffer::SpdyBuffer(const char* data, size_t size) :
  67     shared_frame_(new SharedFrame()),
  68     offset_(0) {
  69   CHECK_GT(size, 0u);
  70   CHECK_LE(size, kMaxSpdyFrameSize);
  71   shared_frame_->data = MakeSpdyFrame(data, size);
  72 }
  73
  74 SpdyBuffer::~SpdyBuffer() {
  75   if (GetRemainingSize() > 0)
  76     ConsumeHelper(GetRemainingSize(), DISCARD);
  77 }
  78
  79 const char* SpdyBuffer::GetRemainingData() const {
  80   return shared_frame_->data->data() + offset_;
  81 }
  82
  83 size_t SpdyBuffer::GetRemainingSize() const {
  84   return shared_frame_->data->size() - offset_;
  85 }
  86
  87 void SpdyBuffer::AddConsumeCallback(const ConsumeCallback& consume_callback) {
  88   consume_callbacks_.push_back(consume_callback);
  89 }
  90
  91 void SpdyBuffer::Consume(size_t consume_size) {
  92   // TODO(pkasting): Remove ScopedTracker below once crbug.com/457517 is fixed.
  93   tracked_objects::ScopedTracker tracking_profile(
  94       FROM_HERE_WITH_EXPLICIT_FUNCTION("457517 SpdyBuffer::Consume"));
  95   ConsumeHelper(consume_size, CONSUME);
  96 };
  97
  98 IOBuffer* SpdyBuffer::GetIOBufferForRemainingData() {
  99   return new SharedFrameIOBuffer(shared_frame_, offset_);
 100 }
 101
 102 void SpdyBuffer::ConsumeHelper(size_t consume_size,
 103                                ConsumeSource consume_source) {
 104   DCHECK_GE(consume_size, 1u);
 105   DCHECK_LE(consume_size, GetRemainingSize());
 106   offset_ += consume_size;
 107   for (std::vector<ConsumeCallback>::const_iterator it =
 108            consume_callbacks_.begin(); it != consume_callbacks_.end(); ++it) {
 109     it->Run(consume_size, consume_source);
 110   }
 111 };
 112
 113 }  // namespace net