blob: ef7a6f54d9ee4f5d4828fb27791c017490476d84 [file] [log] [blame]
/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <private/gui/BitTube.h>
#include <stdint.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <utils/Errors.h>
#include <binder/Parcel.h>
namespace android {
namespace gui {
// Socket buffer size. The default is typically about 128KB, which is much larger than we really
// need. So we make it smaller.
static const size_t DEFAULT_SOCKET_BUFFER_SIZE = 4 * 1024;
BitTube::BitTube(size_t bufsize) {
init(bufsize, bufsize);
}
BitTube::BitTube(DefaultSizeType) : BitTube(DEFAULT_SOCKET_BUFFER_SIZE) {}
BitTube::BitTube(const Parcel& data) {
readFromParcel(&data);
}
void BitTube::init(size_t rcvbuf, size_t sndbuf) {
int sockets[2];
if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sockets) == 0) {
size_t size = DEFAULT_SOCKET_BUFFER_SIZE;
setsockopt(sockets[0], SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf));
setsockopt(sockets[1], SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf));
// since we don't use the "return channel", we keep it small...
setsockopt(sockets[0], SOL_SOCKET, SO_SNDBUF, &size, sizeof(size));
setsockopt(sockets[1], SOL_SOCKET, SO_RCVBUF, &size, sizeof(size));
fcntl(sockets[0], F_SETFL, O_NONBLOCK);
fcntl(sockets[1], F_SETFL, O_NONBLOCK);
mReceiveFd.reset(sockets[0]);
mSendFd.reset(sockets[1]);
} else {
mReceiveFd.reset();
ALOGE("BitTube: pipe creation failed (%s)", strerror(errno));
}
}
status_t BitTube::initCheck() const {
if (mReceiveFd < 0) {
return status_t(mReceiveFd);
}
return NO_ERROR;
}
int BitTube::getFd() const {
return mReceiveFd;
}
int BitTube::getSendFd() const {
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 {
len = ::send(mSendFd, vaddr, size, MSG_DONTWAIT | MSG_NOSIGNAL);
// cannot return less than size, since we're using SOCK_SEQPACKET
err = len < 0 ? errno : 0;
} while (err == EINTR);
return err == 0 ? len : -err;
}
ssize_t BitTube::read(void* vaddr, size_t size) {
ssize_t err, len;
do {
len = ::recv(mReceiveFd, vaddr, size, MSG_DONTWAIT);
err = len < 0 ? errno : 0;
} while (err == EINTR);
if (err == EAGAIN || err == EWOULDBLOCK) {
// EAGAIN means that we have non-blocking I/O but there was no data to be read. Nothing the
// client should care about.
return 0;
}
return err == 0 ? len : -err;
}
status_t BitTube::writeToParcel(Parcel* reply) const {
if (mReceiveFd < 0) return -EINVAL;
status_t result = reply->writeDupFileDescriptor(mReceiveFd);
mReceiveFd.reset();
return result;
}
status_t BitTube::readFromParcel(const Parcel* parcel) {
mReceiveFd.reset(dup(parcel->readFileDescriptor()));
if (mReceiveFd < 0) {
mReceiveFd.reset();
int error = errno;
ALOGE("BitTube::readFromParcel: can't dup file descriptor (%s)", strerror(error));
return -error;
}
return NO_ERROR;
}
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);
// should never happen because of SOCK_SEQPACKET
LOG_ALWAYS_FATAL_IF((size >= 0) && (size % static_cast<ssize_t>(objSize)),
"BitTube::sendObjects(count=%zu, size=%zu), res=%zd (partial events were "
"sent!)",
count, objSize, size);
// ALOGE_IF(size<0, "error %d sending %d events", size, count);
return size < 0 ? size : size / static_cast<ssize_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);
// should never happen because of SOCK_SEQPACKET
LOG_ALWAYS_FATAL_IF((size >= 0) && (size % static_cast<ssize_t>(objSize)),
"BitTube::recvObjects(count=%zu, size=%zu), res=%zd (partial events were "
"received!)",
count, objSize, size);
// ALOGE_IF(size<0, "error %d receiving %d events", size, count);
return size < 0 ? size : size / static_cast<ssize_t>(objSize);
}
} // namespace gui
} // namespace android