| // Copyright 2019 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "garnet/bin/ktrace_provider/device_reader.h" |
| |
| #include <fcntl.h> |
| #include <limits.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| |
| #include "src/lib/files/eintr_wrapper.h" |
| |
| namespace ktrace_provider { |
| |
| namespace { |
| constexpr char kTraceDev[] = "/dev/misc/ktrace"; |
| } // namespace |
| |
| DeviceReader::DeviceReader() |
| : Reader(buffer_, kChunkSize), |
| fd_(open(kTraceDev, O_RDONLY)) { |
| } |
| |
| void DeviceReader::ReadMoreData() { |
| memcpy(buffer_, current_, AvailableBytes()); |
| char* new_marker = buffer_ + AvailableBytes(); |
| |
| while (new_marker < end_) { |
| int bytes_read = |
| HANDLE_EINTR(read(fd_.get(), new_marker, |
| std::distance(const_cast<const char*>(new_marker), |
| end_))); |
| |
| if (bytes_read <= 0) |
| break; |
| |
| new_marker += bytes_read; |
| } |
| |
| marker_ = new_marker; |
| current_ = buffer_; |
| } |
| |
| } // namespace ktrace_provider |