libgui: Remove RefBase from BitTube
Removes RefBase from BitTube, since because it is not a Binder object,
it doesn't need to be reference-counted in this way.
In the process, we rename IDisplayEventConnection::getDataChannel to
IDEC::stealReceiveChannel to make it clearer that this is a non-const
operation on the remote end that removes its access to the receive
channel.
This also adds a couple of methods for moving the receive file
descriptor out of one BitTube and into another, since this is the
essence of the IDisplayEventConnection::stealReceiveChannel method,
and now with C++11 move semantics, we can do this without needing to
return an sp<> from EventThread's implementation of stealReceiveChannel.
Test: m -j + manual testing
Change-Id: Ibaaca2a14fb6155052fe5434c14bc3e671b43743
diff --git a/libs/gui/BitTube.cpp b/libs/gui/BitTube.cpp
index c023711..ef7a6f5 100644
--- a/libs/gui/BitTube.cpp
+++ b/libs/gui/BitTube.cpp
@@ -78,6 +78,14 @@
return mSendFd;
}
+base::unique_fd BitTube::moveReceiveFd() {
+ return std::move(mReceiveFd);
+}
+
+void BitTube::setReceiveFd(base::unique_fd&& receiveFd) {
+ mReceiveFd = std::move(receiveFd);
+}
+
ssize_t BitTube::write(void const* vaddr, size_t size) {
ssize_t err, len;
do {
@@ -121,8 +129,7 @@
return NO_ERROR;
}
-ssize_t BitTube::sendObjects(const sp<BitTube>& tube, void const* events, size_t count,
- size_t objSize) {
+ssize_t BitTube::sendObjects(BitTube* tube, void const* events, size_t count, size_t objSize) {
const char* vaddr = reinterpret_cast<const char*>(events);
ssize_t size = tube->write(vaddr, count * objSize);
@@ -136,7 +143,7 @@
return size < 0 ? size : size / static_cast<ssize_t>(objSize);
}
-ssize_t BitTube::recvObjects(const sp<BitTube>& tube, void* events, size_t count, size_t objSize) {
+ssize_t BitTube::recvObjects(BitTube* tube, void* events, size_t count, size_t objSize) {
char* vaddr = reinterpret_cast<char*>(events);
ssize_t size = tube->read(vaddr, count * objSize);
diff --git a/libs/gui/DisplayEventReceiver.cpp b/libs/gui/DisplayEventReceiver.cpp
index a3ae68c..1507d51 100644
--- a/libs/gui/DisplayEventReceiver.cpp
+++ b/libs/gui/DisplayEventReceiver.cpp
@@ -37,7 +37,8 @@
if (sf != NULL) {
mEventConnection = sf->createDisplayEventConnection();
if (mEventConnection != NULL) {
- mEventConnection->getDataChannel(&mDataChannel);
+ mDataChannel = std::make_unique<gui::BitTube>();
+ mEventConnection->stealReceiveChannel(mDataChannel.get());
}
}
}
@@ -80,16 +81,16 @@
ssize_t DisplayEventReceiver::getEvents(DisplayEventReceiver::Event* events,
size_t count) {
- return DisplayEventReceiver::getEvents(mDataChannel, events, count);
+ return DisplayEventReceiver::getEvents(mDataChannel.get(), events, count);
}
-ssize_t DisplayEventReceiver::getEvents(const sp<gui::BitTube>& dataChannel,
+ssize_t DisplayEventReceiver::getEvents(gui::BitTube* dataChannel,
Event* events, size_t count)
{
return gui::BitTube::recvObjects(dataChannel, events, count);
}
-ssize_t DisplayEventReceiver::sendEvents(const sp<gui::BitTube>& dataChannel,
+ssize_t DisplayEventReceiver::sendEvents(gui::BitTube* dataChannel,
Event const* events, size_t count)
{
return gui::BitTube::sendObjects(dataChannel, events, count);
diff --git a/libs/gui/IDisplayEventConnection.cpp b/libs/gui/IDisplayEventConnection.cpp
index d3ee39c..a197426 100644
--- a/libs/gui/IDisplayEventConnection.cpp
+++ b/libs/gui/IDisplayEventConnection.cpp
@@ -22,7 +22,11 @@
namespace android {
-enum { GET_DATA_CHANNEL = IBinder::FIRST_CALL_TRANSACTION, SET_VSYNC_RATE, REQUEST_NEXT_VSYNC };
+enum {
+ STEAL_RECEIVE_CHANNEL = IBinder::FIRST_CALL_TRANSACTION,
+ SET_VSYNC_RATE,
+ REQUEST_NEXT_VSYNC
+};
class BpDisplayEventConnection : public BpInterface<IDisplayEventConnection> {
public:
@@ -31,11 +35,11 @@
~BpDisplayEventConnection() override;
- status_t getDataChannel(sp<gui::BitTube>* outChannel) const override {
+ status_t stealReceiveChannel(gui::BitTube* outChannel) override {
Parcel data, reply;
data.writeInterfaceToken(IDisplayEventConnection::getInterfaceDescriptor());
- remote()->transact(GET_DATA_CHANNEL, data, &reply);
- *outChannel = new gui::BitTube(reply);
+ remote()->transact(STEAL_RECEIVE_CHANNEL, data, &reply);
+ outChannel->readFromParcel(&reply);
return NO_ERROR;
}
@@ -63,11 +67,11 @@
status_t BnDisplayEventConnection::onTransact(uint32_t code, const Parcel& data, Parcel* reply,
uint32_t flags) {
switch (code) {
- case GET_DATA_CHANNEL: {
+ case STEAL_RECEIVE_CHANNEL: {
CHECK_INTERFACE(IDisplayEventConnection, data, reply);
- sp<gui::BitTube> channel;
- getDataChannel(&channel);
- channel->writeToParcel(reply);
+ gui::BitTube channel;
+ stealReceiveChannel(&channel);
+ channel.writeToParcel(reply);
return NO_ERROR;
}
case SET_VSYNC_RATE: {
diff --git a/libs/gui/include/private/gui/BitTube.h b/libs/gui/include/private/gui/BitTube.h
index e93dc5f..13c0162 100644
--- a/libs/gui/include/private/gui/BitTube.h
+++ b/libs/gui/include/private/gui/BitTube.h
@@ -16,14 +16,9 @@
#pragma once
-#include <stdint.h>
-#include <sys/types.h>
-
-#include <android/log.h>
#include <android-base/unique_fd.h>
#include <binder/Parcelable.h>
#include <utils/Errors.h>
-#include <utils/RefBase.h>
namespace android {
@@ -31,7 +26,7 @@
namespace gui {
-class BitTube : public RefBase, public Parcelable {
+class BitTube : public Parcelable {
public:
// creates an uninitialized BitTube (to unparcel into)
BitTube() = default;
@@ -57,16 +52,22 @@
// get the send file-descriptor.
int getSendFd() const;
+ // moves the receive file descriptor out of this BitTube
+ base::unique_fd moveReceiveFd();
+
+ // resets this BitTube's receive file descriptor to receiveFd
+ void setReceiveFd(base::unique_fd&& receiveFd);
+
// send objects (sized blobs). All objects are guaranteed to be written or the call fails.
template <typename T>
- static ssize_t sendObjects(const sp<BitTube>& tube, T const* events, size_t count) {
+ static ssize_t sendObjects(BitTube* tube, T const* events, size_t count) {
return sendObjects(tube, events, count, sizeof(T));
}
// receive objects (sized blobs). If the receiving buffer isn't large enough, excess messages
// are silently discarded.
template <typename T>
- static ssize_t recvObjects(const sp<BitTube>& tube, T* events, size_t count) {
+ static ssize_t recvObjects(BitTube* tube, T* events, size_t count) {
return recvObjects(tube, events, count, sizeof(T));
}
@@ -87,10 +88,9 @@
base::unique_fd mSendFd;
mutable base::unique_fd mReceiveFd;
- static ssize_t sendObjects(const sp<BitTube>& tube, void const* events, size_t count,
- size_t objSize);
+ static ssize_t sendObjects(BitTube* tube, void const* events, size_t count, size_t objSize);
- static ssize_t recvObjects(const sp<BitTube>& tube, void* events, size_t count, size_t objSize);
+ static ssize_t recvObjects(BitTube* tube, void* events, size_t count, size_t objSize);
};
} // namespace gui