replicant-frameworks_native/libs/gui/BitTube.cpp

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/*
* 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 <stdint.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <utils/Errors.h>
#include <binder/Parcel.h>
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#include <gui/BitTube.h>
namespace android {
// ----------------------------------------------------------------------------
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BitTube::BitTube()
: mSendFd(-1), mReceiveFd(-1)
{
int fds[2];
if (pipe(fds) == 0) {
mReceiveFd = fds[0];
mSendFd = fds[1];
fcntl(mReceiveFd, F_SETFL, O_NONBLOCK);
fcntl(mSendFd, F_SETFL, O_NONBLOCK);
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} else {
mReceiveFd = -errno;
LOGE("BitTube: pipe creation failed (%s)", strerror(-mReceiveFd));
}
}
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BitTube::BitTube(const Parcel& data)
: mSendFd(-1), mReceiveFd(-1)
{
mReceiveFd = dup(data.readFileDescriptor());
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if (mReceiveFd >= 0) {
fcntl(mReceiveFd, F_SETFL, O_NONBLOCK);
} else {
mReceiveFd = -errno;
LOGE("BitTube(Parcel): can't dup filedescriptor (%s)",
strerror(-mReceiveFd));
}
}
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BitTube::~BitTube()
{
if (mSendFd >= 0)
close(mSendFd);
if (mReceiveFd >= 0)
close(mReceiveFd);
}
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status_t BitTube::initCheck() const
{
if (mReceiveFd < 0) {
return status_t(mReceiveFd);
}
return NO_ERROR;
}
int BitTube::getFd() const
{
return mReceiveFd;
}
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ssize_t BitTube::write(void const* vaddr, size_t size)
{
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ssize_t err, len;
do {
len = ::write(mSendFd, vaddr, size);
err = len < 0 ? errno : 0;
} while (err == EINTR);
return err == 0 ? len : -err;
}
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ssize_t BitTube::read(void* vaddr, size_t size)
{
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ssize_t err, len;
do {
len = ::read(mReceiveFd, vaddr, size);
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;
}
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return err == 0 ? len : -err;
}
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status_t BitTube::writeToParcel(Parcel* reply) const
{
if (mReceiveFd < 0)
return -EINVAL;
status_t result = reply->writeDupFileDescriptor(mReceiveFd);
close(mReceiveFd);
mReceiveFd = -1;
return result;
}
// ----------------------------------------------------------------------------
}; // namespace android