cmds/incidentd/src/FdBuffer.cpp - LeafOS-Project/android_frameworks_base - Gitiles

 /*
  * Copyright (C) 2016 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.
  */
 #define DEBUG false
 #include "Log.h"

 #include "FdBuffer.h"

 #include <cutils/log.h>
 #include <utils/SystemClock.h>

 #include <fcntl.h>
 #include <poll.h>
 #include <unistd.h>
 #include <wait.h>

 namespace android {
 namespace os {
 namespace incidentd {

 const ssize_t BUFFER_SIZE = 16 * 1024;  // 16 KB
 const ssize_t MAX_BUFFER_COUNT = 256;   // 4 MB max

 FdBuffer::FdBuffer()
     : mBuffer(BUFFER_SIZE), mStartTime(-1), mFinishTime(-1), mTimedOut(false), mTruncated(false) {}

 FdBuffer::~FdBuffer() {}

 status_t FdBuffer::read(int fd, int64_t timeout) {
     struct pollfd pfds = {.fd = fd, .events = POLLIN};
     mStartTime = uptimeMillis();

     fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);

     while (true) {
         if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
             mTruncated = true;
             break;
         }
         if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

         int64_t remainingTime = (mStartTime + timeout) - uptimeMillis();
         if (remainingTime <= 0) {
             VLOG("timed out due to long read");
             mTimedOut = true;
             break;
         }

         int count = poll(&pfds, 1, remainingTime);
         if (count == 0) {
             VLOG("timed out due to block calling poll");
             mTimedOut = true;
             break;
         } else if (count < 0) {
             VLOG("poll failed: %s", strerror(errno));
             return -errno;
         } else {
             if ((pfds.revents & POLLERR) != 0) {
                 VLOG("return event has error %s", strerror(errno));
                 return errno != 0 ? -errno : UNKNOWN_ERROR;
             } else {
                 ssize_t amt = TEMP_FAILURE_RETRY(
                         ::read(fd, mBuffer.writeBuffer(), mBuffer.currentToWrite()));
                 if (amt < 0) {
                     if (errno == EAGAIN || errno == EWOULDBLOCK) {
                         continue;
                     } else {
                         VLOG("Fail to read %d: %s", fd, strerror(errno));
                         return -errno;
                     }
                 } else if (amt == 0) {
                     VLOG("Reached EOF of fd=%d", fd);
                     break;
                 }
                 mBuffer.wp()->move(amt);
             }
         }
     }
     mFinishTime = uptimeMillis();
     return NO_ERROR;
 }

 status_t FdBuffer::readFully(int fd) {
     mStartTime = uptimeMillis();

     while (true) {
         if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
             // Don't let it get too big.
             mTruncated = true;
             VLOG("Truncating data");
             break;
         }
         if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

         ssize_t amt =
                 TEMP_FAILURE_RETRY(::read(fd, mBuffer.writeBuffer(), mBuffer.currentToWrite()));
         if (amt < 0) {
             VLOG("Fail to read %d: %s", fd, strerror(errno));
             return -errno;
         } else if (amt == 0) {
             VLOG("Done reading %zu bytes", mBuffer.size());
             // We're done.
             break;
         }
         mBuffer.wp()->move(amt);
     }

     mFinishTime = uptimeMillis();
     return NO_ERROR;
 }

 status_t FdBuffer::readProcessedDataInStream(int fd, unique_fd toFd, unique_fd fromFd,
                                              int64_t timeoutMs, const bool isSysfs) {
     struct pollfd pfds[] = {
             {.fd = fd, .events = POLLIN},
             {.fd = toFd.get(), .events = POLLOUT},
             {.fd = fromFd.get(), .events = POLLIN},
     };

     mStartTime = uptimeMillis();

     // mark all fds non blocking
     fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
     fcntl(toFd.get(), F_SETFL, fcntl(toFd.get(), F_GETFL, 0) | O_NONBLOCK);
     fcntl(fromFd.get(), F_SETFL, fcntl(fromFd.get(), F_GETFL, 0) | O_NONBLOCK);

     // A circular buffer holds data read from fd and writes to parsing process
     uint8_t cirBuf[BUFFER_SIZE];
     size_t cirSize = 0;
     int rpos = 0, wpos = 0;

     // This is the buffer used to store processed data
     while (true) {
         if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
             mTruncated = true;
             break;
         }
         if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

         int64_t remainingTime = (mStartTime + timeoutMs) - uptimeMillis();
         if (remainingTime <= 0) {
             VLOG("timed out due to long read");
             mTimedOut = true;
             break;
         }

         // wait for any pfds to be ready to perform IO
         int count = poll(pfds, 3, remainingTime);
         if (count == 0) {
             VLOG("timed out due to block calling poll");
             mTimedOut = true;
             break;
         } else if (count < 0) {
             VLOG("Fail to poll: %s", strerror(errno));
             return -errno;
         }

         // make sure no errors occur on any fds
         for (int i = 0; i < 3; ++i) {
             if ((pfds[i].revents & POLLERR) != 0) {
                 if (i == 0 && isSysfs) {
                     VLOG("fd %d is sysfs, ignore its POLLERR return value", fd);
                     continue;
                 }
                 VLOG("fd[%d]=%d returns error events: %s", i, fd, strerror(errno));
                 return errno != 0 ? -errno : UNKNOWN_ERROR;
             }
         }

         // read from fd
         if (cirSize != BUFFER_SIZE && pfds[0].fd != -1) {
             ssize_t amt;
             if (rpos >= wpos) {
                 amt = TEMP_FAILURE_RETRY(::read(fd, cirBuf + rpos, BUFFER_SIZE - rpos));
             } else {
                 amt = TEMP_FAILURE_RETRY(::read(fd, cirBuf + rpos, wpos - rpos));
             }
             if (amt < 0) {
                 if (!(errno == EAGAIN || errno == EWOULDBLOCK)) {
                     VLOG("Fail to read fd %d: %s", fd, strerror(errno));
                     return -errno;
                 }  // otherwise just continue
             } else if (amt == 0) {
                 VLOG("Reached EOF of input file %d", fd);
                 pfds[0].fd = -1;  // reach EOF so don't have to poll pfds[0].
             } else {
                 rpos += amt;
                 cirSize += amt;
             }
         }

         // write to parsing process
         if (cirSize > 0 && pfds[1].fd != -1) {
             ssize_t amt;
             if (rpos > wpos) {
                 amt = TEMP_FAILURE_RETRY(::write(toFd.get(), cirBuf + wpos, rpos - wpos));
             } else {
                 amt = TEMP_FAILURE_RETRY(::write(toFd.get(), cirBuf + wpos, BUFFER_SIZE - wpos));
             }
             if (amt < 0) {
                 if (!(errno == EAGAIN || errno == EWOULDBLOCK)) {
                     VLOG("Fail to write toFd %d: %s", toFd.get(), strerror(errno));
                     return -errno;
                 }  // otherwise just continue
             } else {
                 wpos += amt;
                 cirSize -= amt;
             }
         }

         // if buffer is empty and fd is closed, close write fd.
         if (cirSize == 0 && pfds[0].fd == -1 && pfds[1].fd != -1) {
             VLOG("Close write pipe %d", toFd.get());
             toFd.reset();
             pfds[1].fd = -1;
         }

         // circular buffer, reset rpos and wpos
         if (rpos >= BUFFER_SIZE) {
             rpos = 0;
         }
         if (wpos >= BUFFER_SIZE) {
             wpos = 0;
         }

         // read from parsing process
         ssize_t amt = TEMP_FAILURE_RETRY(
                 ::read(fromFd.get(), mBuffer.writeBuffer(), mBuffer.currentToWrite()));
         if (amt < 0) {
             if (!(errno == EAGAIN || errno == EWOULDBLOCK)) {
                 VLOG("Fail to read fromFd %d: %s", fromFd.get(), strerror(errno));
                 return -errno;
             }  // otherwise just continue
         } else if (amt == 0) {
             VLOG("Reached EOF of fromFd %d", fromFd.get());
             break;
         } else {
             mBuffer.wp()->move(amt);
         }
     }

     mFinishTime = uptimeMillis();
     return NO_ERROR;
 }

 size_t FdBuffer::size() const { return mBuffer.size(); }

 EncodedBuffer::iterator FdBuffer::data() const { return mBuffer.begin(); }

 }  // namespace incidentd
 }  // namespace os
 }  // namespace android
	/*
	* Copyright (C) 2016 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.
	*/
	#define DEBUG false
	#include "Log.h"

	#include "FdBuffer.h"

	#include <cutils/log.h>
	#include <utils/SystemClock.h>

	#include <fcntl.h>
	#include <poll.h>
	#include <unistd.h>
	#include <wait.h>

	namespace android {
	namespace os {
	namespace incidentd {

	const ssize_t BUFFER_SIZE = 16 * 1024; // 16 KB
	const ssize_t MAX_BUFFER_COUNT = 256; // 4 MB max

	FdBuffer::FdBuffer()
	: mBuffer(BUFFER_SIZE), mStartTime(-1), mFinishTime(-1), mTimedOut(false), mTruncated(false) {}

	FdBuffer::~FdBuffer() {}

	status_t FdBuffer::read(int fd, int64_t timeout) {
	struct pollfd pfds = {.fd = fd, .events = POLLIN};
	mStartTime = uptimeMillis();

	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) \| O_NONBLOCK);

	while (true) {
	if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
	mTruncated = true;
	break;
	}
	if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

	int64_t remainingTime = (mStartTime + timeout) - uptimeMillis();
	if (remainingTime <= 0) {
	VLOG("timed out due to long read");
	mTimedOut = true;
	break;
	}

	int count = poll(&pfds, 1, remainingTime);
	if (count == 0) {
	VLOG("timed out due to block calling poll");
	mTimedOut = true;
	break;
	} else if (count < 0) {
	VLOG("poll failed: %s", strerror(errno));
	return -errno;
	} else {
	if ((pfds.revents & POLLERR) != 0) {
	VLOG("return event has error %s", strerror(errno));
	return errno != 0 ? -errno : UNKNOWN_ERROR;
	} else {
	ssize_t amt = TEMP_FAILURE_RETRY(
	::read(fd, mBuffer.writeBuffer(), mBuffer.currentToWrite()));
	if (amt < 0) {
	if (errno == EAGAIN \|\| errno == EWOULDBLOCK) {
	continue;
	} else {
	VLOG("Fail to read %d: %s", fd, strerror(errno));
	return -errno;
	}
	} else if (amt == 0) {
	VLOG("Reached EOF of fd=%d", fd);
	break;
	}
	mBuffer.wp()->move(amt);
	}
	}
	}
	mFinishTime = uptimeMillis();
	return NO_ERROR;
	}

	status_t FdBuffer::readFully(int fd) {
	mStartTime = uptimeMillis();

	while (true) {
	if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
	// Don't let it get too big.
	mTruncated = true;
	VLOG("Truncating data");
	break;
	}
	if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

	ssize_t amt =
	TEMP_FAILURE_RETRY(::read(fd, mBuffer.writeBuffer(), mBuffer.currentToWrite()));
	if (amt < 0) {
	VLOG("Fail to read %d: %s", fd, strerror(errno));
	return -errno;
	} else if (amt == 0) {
	VLOG("Done reading %zu bytes", mBuffer.size());
	// We're done.
	break;
	}
	mBuffer.wp()->move(amt);
	}

	mFinishTime = uptimeMillis();
	return NO_ERROR;
	}

	status_t FdBuffer::readProcessedDataInStream(int fd, unique_fd toFd, unique_fd fromFd,
	int64_t timeoutMs, const bool isSysfs) {
	struct pollfd pfds[] = {
	{.fd = fd, .events = POLLIN},
	{.fd = toFd.get(), .events = POLLOUT},
	{.fd = fromFd.get(), .events = POLLIN},
	};

	mStartTime = uptimeMillis();

	// mark all fds non blocking
	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) \| O_NONBLOCK);
	fcntl(toFd.get(), F_SETFL, fcntl(toFd.get(), F_GETFL, 0) \| O_NONBLOCK);
	fcntl(fromFd.get(), F_SETFL, fcntl(fromFd.get(), F_GETFL, 0) \| O_NONBLOCK);

	// A circular buffer holds data read from fd and writes to parsing process
	uint8_t cirBuf[BUFFER_SIZE];
	size_t cirSize = 0;
	int rpos = 0, wpos = 0;

	// This is the buffer used to store processed data
	while (true) {
	if (mBuffer.size() >= MAX_BUFFER_COUNT * BUFFER_SIZE) {
	mTruncated = true;
	break;
	}
	if (mBuffer.writeBuffer() == NULL) return NO_MEMORY;

	int64_t remainingTime = (mStartTime + timeoutMs) - uptimeMillis();
	if (remainingTime <= 0) {
	VLOG("timed out due to long read");
	mTimedOut = true;
	break;
	}

	// wait for any pfds to be ready to perform IO
	int count = poll(pfds, 3, remainingTime);
	if (count == 0) {
	VLOG("timed out due to block calling poll");
	mTimedOut = true;
	break;
	} else if (count < 0) {
	VLOG("Fail to poll: %s", strerror(errno));
	return -errno;
	}

	// make sure no errors occur on any fds
	for (int i = 0; i < 3; ++i) {
	if ((pfds[i].revents & POLLERR) != 0) {
	if (i == 0 && isSysfs) {
	VLOG("fd %d is sysfs, ignore its POLLERR return value", fd);
	continue;
	}
	VLOG("fd[%d]=%d returns error events: %s", i, fd, strerror(errno));
	return errno != 0 ? -errno : UNKNOWN_ERROR;
	}
	}

	// read from fd
	if (cirSize != BUFFER_SIZE && pfds[0].fd != -1) {
	ssize_t amt;
	if (rpos >= wpos) {
	amt = TEMP_FAILURE_RETRY(::read(fd, cirBuf + rpos, BUFFER_SIZE - rpos));
	} else {
	amt = TEMP_FAILURE_RETRY(::read(fd, cirBuf + rpos, wpos - rpos));
	}
	if (amt < 0) {
	if (!(errno == EAGAIN \|\| errno == EWOULDBLOCK)) {
	VLOG("Fail to read fd %d: %s", fd, strerror(errno));
	return -errno;
	} // otherwise just continue
	} else if (amt == 0) {
	VLOG("Reached EOF of input file %d", fd);
	pfds[0].fd = -1; // reach EOF so don't have to poll pfds[0].
	} else {
	rpos += amt;
	cirSize += amt;
	}
	}

	// write to parsing process
	if (cirSize > 0 && pfds[1].fd != -1) {
	ssize_t amt;
	if (rpos > wpos) {
	amt = TEMP_FAILURE_RETRY(::write(toFd.get(), cirBuf + wpos, rpos - wpos));
	} else {
	amt = TEMP_FAILURE_RETRY(::write(toFd.get(), cirBuf + wpos, BUFFER_SIZE - wpos));
	}
	if (amt < 0) {
	if (!(errno == EAGAIN \|\| errno == EWOULDBLOCK)) {
	VLOG("Fail to write toFd %d: %s", toFd.get(), strerror(errno));
	return -errno;
	} // otherwise just continue
	} else {
	wpos += amt;
	cirSize -= amt;
	}
	}

	// if buffer is empty and fd is closed, close write fd.
	if (cirSize == 0 && pfds[0].fd == -1 && pfds[1].fd != -1) {
	VLOG("Close write pipe %d", toFd.get());
	toFd.reset();
	pfds[1].fd = -1;
	}

	// circular buffer, reset rpos and wpos
	if (rpos >= BUFFER_SIZE) {
	rpos = 0;
	}
	if (wpos >= BUFFER_SIZE) {
	wpos = 0;
	}

	// read from parsing process
	ssize_t amt = TEMP_FAILURE_RETRY(
	::read(fromFd.get(), mBuffer.writeBuffer(), mBuffer.currentToWrite()));
	if (amt < 0) {
	if (!(errno == EAGAIN \|\| errno == EWOULDBLOCK)) {
	VLOG("Fail to read fromFd %d: %s", fromFd.get(), strerror(errno));
	return -errno;
	} // otherwise just continue
	} else if (amt == 0) {
	VLOG("Reached EOF of fromFd %d", fromFd.get());
	break;
	} else {
	mBuffer.wp()->move(amt);
	}
	}

	mFinishTime = uptimeMillis();
	return NO_ERROR;
	}

	size_t FdBuffer::size() const { return mBuffer.size(); }

	EncodedBuffer::iterator FdBuffer::data() const { return mBuffer.begin(); }

	} // namespace incidentd
	} // namespace os
	} // namespace android