| /* |
| * 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. |
| */ |
| #pragma once |
| |
| #ifndef FD_BUFFER_H |
| #define FD_BUFFER_H |
| |
| #include <android/util/EncodedBuffer.h> |
| #include <utils/Errors.h> |
| |
| using namespace android; |
| using namespace android::util; |
| using namespace std; |
| |
| /** |
| * Reads data from fd into a buffer, fd must be closed explicitly. |
| */ |
| class FdBuffer { |
| public: |
| FdBuffer(); |
| ~FdBuffer(); |
| |
| /** |
| * Read the data until the timeout is hit or we hit eof. |
| * Returns NO_ERROR if there were no errors or if we timed out. |
| * Will mark the file O_NONBLOCK. |
| */ |
| status_t read(int fd, int64_t timeoutMs); |
| |
| /** |
| * Read processed results by streaming data to a parsing process, e.g. incident helper. |
| * The parsing process provides IO fds which are 'toFd' and 'fromFd'. The function |
| * reads original data in 'fd' and writes to parsing process through 'toFd', then it reads |
| * and stores the processed data from 'fromFd' in memory for later usage. |
| * This function behaves in a streaming fashion in order to save memory usage. |
| * Returns NO_ERROR if there were no errors or if we timed out. |
| * |
| * Poll will return POLLERR if fd is from sysfs, handle this edge case. |
| */ |
| status_t readProcessedDataInStream(int fd, int toFd, int fromFd, int64_t timeoutMs, |
| const bool isSysfs = false); |
| |
| /** |
| * Whether we timed out. |
| */ |
| bool timedOut() const { return mTimedOut; } |
| |
| /** |
| * If more than 4 MB is read, we truncate the data and return success. |
| * Downstream tools must handle truncated incident reports as best as possible |
| * anyway because they could be cut off for a lot of reasons and it's best |
| * to get as much useful information out of the system as possible. If this |
| * happens, truncated() will return true so it can be marked. If the data is |
| * exactly 4 MB, truncated is still set. Sorry. |
| */ |
| bool truncated() const { return mTruncated; } |
| |
| /** |
| * How much data was read. |
| */ |
| size_t size() const; |
| |
| /** |
| * How long the read took in milliseconds. |
| */ |
| int64_t durationMs() const { return mFinishTime - mStartTime; } |
| |
| /** |
| * Reader API for data stored in FdBuffer |
| */ |
| EncodedBuffer::iterator data() const; |
| |
| /** |
| * Return the internal buffer, don't call unless you are familiar with EncodedBuffer. |
| */ |
| EncodedBuffer* getInternalBuffer() { return &mBuffer; } |
| |
| private: |
| EncodedBuffer mBuffer; |
| int64_t mStartTime; |
| int64_t mFinishTime; |
| bool mTimedOut; |
| bool mTruncated; |
| }; |
| |
| #endif // FD_BUFFER_H |