content/child/web_data_consumer_handle_impl.cc

   1 // Copyright 2014 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 "content/child/web_data_consumer_handle_impl.h"
   6
   7 #include <limits>
   8 #include "base/bind.h"
   9 #include "base/logging.h"
  10 #include "third_party/mojo/src/mojo/public/c/system/types.h"
  11
  12 namespace content {
  13
  14 using Result = blink::WebDataConsumerHandle::Result;
  15
  16 class WebDataConsumerHandleImpl::Context
  17     : public base::RefCountedThreadSafe<Context> {
  18  public:
  19   explicit Context(Handle handle) : handle_(handle.Pass()) {}
  20
  21   const Handle& handle() { return handle_; }
  22
  23  private:
  24   friend class base::RefCountedThreadSafe<Context>;
  25   ~Context() {}
  26   Handle handle_;
  27
  28   DISALLOW_COPY_AND_ASSIGN(Context);
  29 };
  30
  31 WebDataConsumerHandleImpl::ReaderImpl::ReaderImpl(
  32     scoped_refptr<Context> context,
  33     Client* client)
  34     : context_(context), client_(client) {
  35   if (client_)
  36     StartWatching();
  37 }
  38
  39 WebDataConsumerHandleImpl::ReaderImpl::~ReaderImpl() {
  40 }
  41
  42 Result WebDataConsumerHandleImpl::ReaderImpl::read(void* data,
  43                                                    size_t size,
  44                                                    Flags flags,
  45                                                    size_t* read_size) {
  46   // We need this variable definition to avoid a link error.
  47   const Flags kNone = FlagNone;
  48   DCHECK_EQ(flags, kNone);
  49   DCHECK_LE(size, std::numeric_limits<uint32_t>::max());
  50
  51   *read_size = 0;
  52
  53   uint32_t size_to_pass = size;
  54   MojoReadDataFlags flags_to_pass = MOJO_READ_DATA_FLAG_NONE;
  55   MojoResult rv = mojo::ReadDataRaw(context_->handle().get(), data,
  56                                     &size_to_pass, flags_to_pass);
  57   if (rv == MOJO_RESULT_OK)
  58     *read_size = size_to_pass;
  59
  60   return HandleReadResult(rv);
  61 }
  62
  63 Result WebDataConsumerHandleImpl::ReaderImpl::beginRead(const void** buffer,
  64                                                         Flags flags,
  65                                                         size_t* available) {
  66   // We need this variable definition to avoid a link error.
  67   const Flags kNone = FlagNone;
  68   DCHECK_EQ(flags, kNone);
  69
  70   *buffer = nullptr;
  71   *available = 0;
  72
  73   uint32_t size_to_pass = 0;
  74   MojoReadDataFlags flags_to_pass = MOJO_READ_DATA_FLAG_NONE;
  75
  76   MojoResult rv = mojo::BeginReadDataRaw(context_->handle().get(), buffer,
  77                                          &size_to_pass, flags_to_pass);
  78   if (rv == MOJO_RESULT_OK)
  79     *available = size_to_pass;
  80   return HandleReadResult(rv);
  81 }
  82
  83 Result WebDataConsumerHandleImpl::ReaderImpl::endRead(size_t read_size) {
  84   MojoResult rv = mojo::EndReadDataRaw(context_->handle().get(), read_size);
  85   return rv == MOJO_RESULT_OK ? Ok : UnexpectedError;
  86 }
  87
  88 Result WebDataConsumerHandleImpl::ReaderImpl::HandleReadResult(
  89     MojoResult mojo_result) {
  90   switch (mojo_result) {
  91     case MOJO_RESULT_OK:
  92       return Ok;
  93     case MOJO_RESULT_FAILED_PRECONDITION:
  94       return Done;
  95     case MOJO_RESULT_BUSY:
  96       return Busy;
  97     case MOJO_RESULT_SHOULD_WAIT:
  98       if (client_)
  99         StartWatching();
 100       return ShouldWait;
 101     case MOJO_RESULT_RESOURCE_EXHAUSTED:
 102       return ResourceExhausted;
 103     default:
 104       return UnexpectedError;
 105   }
 106 }
 107
 108 void WebDataConsumerHandleImpl::ReaderImpl::StartWatching() {
 109   handle_watcher_.Start(
 110       context_->handle().get(), MOJO_HANDLE_SIGNAL_READABLE,
 111       MOJO_DEADLINE_INDEFINITE,
 112       base::Bind(&ReaderImpl::OnHandleGotReadable, base::Unretained(this)));
 113 }
 114
 115 void WebDataConsumerHandleImpl::ReaderImpl::OnHandleGotReadable(MojoResult) {
 116   DCHECK(client_);
 117   client_->didGetReadable();
 118 }
 119
 120 WebDataConsumerHandleImpl::WebDataConsumerHandleImpl(Handle handle)
 121     : context_(new Context(handle.Pass())) {
 122 }
 123
 124 WebDataConsumerHandleImpl::~WebDataConsumerHandleImpl() {
 125 }
 126
 127 scoped_ptr<blink::WebDataConsumerHandle::Reader>
 128 WebDataConsumerHandleImpl::ObtainReader(Client* client) {
 129   return make_scoped_ptr(obtainReaderInternal(client));
 130 }
 131
 132 WebDataConsumerHandleImpl::ReaderImpl*
 133 WebDataConsumerHandleImpl::obtainReaderInternal(Client* client) {
 134   return new ReaderImpl(context_, client);
 135 }
 136
 137 }  // namespace content