| /* |
| * 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 <log/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 = 1536; // 24 MB max |
| |
| FdBuffer::FdBuffer() |
| :mBuffer(new EncodedBuffer(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; |
| VLOG("Truncating data"); |
| break; |
| } |
| if (mBuffer->writeBuffer() == NULL) { |
| VLOG("No memory"); |
| return NO_MEMORY; |
| } |
| |
| int64_t remainingTime = (mStartTime + timeout) - uptimeMillis(); |
| if (remainingTime <= 0) { |
| VLOG("timed out due to long read"); |
| mTimedOut = true; |
| break; |
| } |
| |
| int count = TEMP_FAILURE_RETRY(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) { |
| VLOG("No memory"); |
| 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) { |
| VLOG("Truncating data"); |
| mTruncated = true; |
| break; |
| } |
| if (mBuffer->writeBuffer() == NULL) { |
| VLOG("No memory"); |
| 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 = TEMP_FAILURE_RETRY(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; |
| } |
| |
| status_t FdBuffer::write(uint8_t const* buf, size_t size) { |
| return mBuffer->writeRaw(buf, size); |
| } |
| |
| status_t FdBuffer::write(const sp<ProtoReader>& reader) { |
| return mBuffer->writeRaw(reader); |
| } |
| |
| status_t FdBuffer::write(const sp<ProtoReader>& reader, size_t size) { |
| return mBuffer->writeRaw(reader, size); |
| } |
| |
| size_t FdBuffer::size() const { |
| return mBuffer->size(); |
| } |
| |
| sp<EncodedBuffer> FdBuffer::data() const { |
| return mBuffer; |
| } |
| |
| } // namespace incidentd |
| } // namespace os |
| } // namespace android |