Change data pipe wrappers used by SerialConnection to use message pipe.

device/serial/data_sender.cc

Index: device/serial/data_sender.cc
diff --git a/device/serial/data_sender.cc b/device/serial/data_sender.cc
index 409f5f449d1003f45cee750039634bc2e53f9876..18b1a43ef3357543a32a99bd16d95843262e0a35 100644
--- a/device/serial/data_sender.cc
+++ b/device/serial/data_sender.cc
@@ -4,9 +4,10 @@
 
 #include "device/serial/data_sender.h"
 
+#include <algorithm>
+
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
-#include "device/serial/async_waiter.h"
 
 namespace device {
 
@@ -34,10 +35,8 @@ class DataSender::PendingSend {
   // Reports |fatal_error_value_| to |receive_error_callback_|.
   void DispatchFatalError();
 
-  // Attempts to send any data not yet sent to |handle|. Returns MOJO_RESULT_OK
-  // if all data is sent, MOJO_RESULT_SHOULD_WAIT if not all of the data is sent
-  // or the error if one is encountered writing to |handle|.
-  MojoResult SendData(mojo::DataPipeProducerHandle handle);
+  // Attempts to send any data not yet sent to |sink|.
+  bool SendData(serial::DataSink* sink, uint32_t* available_buffer_size);
 
  private:
   // Invoked to update |bytes_acked_| and |num_bytes|.
@@ -55,7 +54,7 @@ class DataSender::PendingSend {
   // The error value to report when DispatchFatalError() is called.
   const int32_t fatal_error_value_;
 
-  // The number of bytes sent to the data pipe.
+  // The number of bytes sent to the DataSink.
   uint32_t bytes_sent_;
 
   // The number of bytes acked.
@@ -67,17 +66,11 @@ DataSender::DataSender(mojo::InterfacePtr<serial::DataSink> sink,
                        int32_t fatal_error_value)
     : sink_(sink.Pass()),
       fatal_error_value_(fatal_error_value),
+      available_buffer_capacity_(buffer_size),
       shut_down_(false) {
   sink_.set_error_handler(this);
-  MojoCreateDataPipeOptions options = {
-      sizeof(options), MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_NONE, 1, buffer_size,
-  };
-  options.struct_size = sizeof(options);
-  mojo::ScopedDataPipeConsumerHandle remote_handle;
-  MojoResult result = mojo::CreateDataPipe(&options, &handle_, &remote_handle);
-  DCHECK_EQ(MOJO_RESULT_OK, result);
-  sink_->Init(remote_handle.Pass());
   sink_.set_client(this);
+  sink_->Init(buffer_size);
 }
 
 DataSender::~DataSender() {
@@ -115,6 +108,7 @@ void DataSender::ReportBytesSent(uint32_t bytes_sent) {
   if (shut_down_)
     return;
 
+  available_buffer_capacity_ += bytes_sent;
   while (bytes_sent != 0 && !sends_awaiting_ack_.empty() &&
          sends_awaiting_ack_.front()->ReportBytesSent(&bytes_sent)) {
     sends_awaiting_ack_.pop();
@@ -133,27 +127,29 @@ void DataSender::ReportBytesSent(uint32_t bytes_sent) {
   }
   if (pending_sends_.empty() && sends_awaiting_ack_.empty())
     RunCancelCallback();
+  SendInternal();
 }
 
 void DataSender::ReportBytesSentAndError(
     uint32_t bytes_sent,
     int32_t error,
-    const mojo::Callback<void(uint32_t)>& callback) {
+    const mojo::Callback<void()>& callback) {
   if (shut_down_)
     return;
 
-  uint32_t bytes_to_flush = 0;
+  available_buffer_capacity_ += bytes_sent;
   while (!sends_awaiting_ack_.empty()) {
-    bytes_to_flush += sends_awaiting_ack_.front()->ReportBytesSentAndError(
-        &bytes_sent, error);
+    available_buffer_capacity_ +=
+        sends_awaiting_ack_.front()->ReportBytesSentAndError(&bytes_sent,
+                                                             error);
     sends_awaiting_ack_.pop();
   }
   while (!pending_sends_.empty()) {
-    bytes_to_flush +=
+    available_buffer_capacity_ +=
         pending_sends_.front()->ReportBytesSentAndError(&bytes_sent, error);
     pending_sends_.pop();
   }
-  callback.Run(bytes_to_flush);
+  callback.Run();
   RunCancelCallback();
 }
 
@@ -162,33 +158,15 @@ void DataSender::OnConnectionError() {
 }
 
 void DataSender::SendInternal() {
-  while (!pending_sends_.empty()) {
-    MojoResult result = pending_sends_.front()->SendData(handle_.get());
-    if (result == MOJO_RESULT_OK) {
+  while (!pending_sends_.empty() && available_buffer_capacity_) {
+    if (pending_sends_.front()->SendData(sink_.get(),
+                                         &available_buffer_capacity_)) {
       sends_awaiting_ack_.push(pending_sends_.front());
       pending_sends_.pop();
-    } else if (result == MOJO_RESULT_SHOULD_WAIT) {
-      waiter_.reset(new AsyncWaiter(
-          handle_.get(),
-          MOJO_HANDLE_SIGNAL_WRITABLE,
-          base::Bind(&DataSender::OnDoneWaiting, base::Unretained(this))));
-      return;
-    } else {
-      ShutDown();
-      return;
     }
   }
 }
 
-void DataSender::OnDoneWaiting(MojoResult result) {
-  waiter_.reset();
-  if (result != MOJO_RESULT_OK) {
-    ShutDown();
-    return;
-  }
-  SendInternal();
-}
-
 void DataSender::RunCancelCallback() {
   DCHECK(pending_sends_.empty() && sends_awaiting_ack_.empty());
   if (pending_cancel_.is_null())
@@ -200,7 +178,6 @@ void DataSender::RunCancelCallback() {
 }
 
 void DataSender::ShutDown() {
-  waiter_.reset();
   shut_down_ = true;
   while (!pending_sends_.empty()) {
     pending_sends_.front()->DispatchFatalError();
@@ -253,18 +230,17 @@ void DataSender::PendingSend::DispatchFatalError() {
       FROM_HERE, base::Bind(error_callback_, 0, fatal_error_value_));
 }
 
-MojoResult DataSender::PendingSend::SendData(
-    mojo::DataPipeProducerHandle handle) {
-  uint32_t bytes_to_send = static_cast<uint32_t>(data_.size()) - bytes_sent_;
-  MojoResult result = mojo::WriteDataRaw(handle,
-                                         data_.data() + bytes_sent_,
-                                         &bytes_to_send,
-                                         MOJO_WRITE_DATA_FLAG_NONE);
-  if (result != MOJO_RESULT_OK)
-    return result;
-
-  bytes_sent_ += bytes_to_send;
-  return bytes_sent_ == data_.size() ? MOJO_RESULT_OK : MOJO_RESULT_SHOULD_WAIT;
+bool DataSender::PendingSend::SendData(serial::DataSink* sink,
+                                       uint32_t* available_buffer_size) {
+  uint32_t num_bytes_to_send =
+      std::min(static_cast<uint32_t>(data_.size() - bytes_sent_),
+               *available_buffer_size);
+  mojo::Array<uint8_t> bytes(num_bytes_to_send);
+  memcpy(&bytes[0], data_.data() + bytes_sent_, num_bytes_to_send);
+  bytes_sent_ += num_bytes_to_send;
+  *available_buffer_size -= num_bytes_to_send;
+  sink->OnData(bytes.Pass());
+  return bytes_sent_ == data_.size();
 }
 
 void DataSender::PendingSend::ReportBytesSentInternal(uint32_t* num_bytes) {