Index: third_party/crashpad/crashpad/util/file/delimited_file_reader.cc |
diff --git a/third_party/crashpad/crashpad/util/file/delimited_file_reader.cc b/third_party/crashpad/crashpad/util/file/delimited_file_reader.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..a55c2a7c44b7b0ba1683ddf5446bcf427b8237ca |
--- /dev/null |
+++ b/third_party/crashpad/crashpad/util/file/delimited_file_reader.cc |
@@ -0,0 +1,109 @@ |
+// Copyright 2017 The Crashpad Authors. All rights reserved. |
+// |
+// 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 "util/file/delimited_file_reader.h" |
+ |
+#include <sys/types.h> |
+ |
+#include <algorithm> |
+#include <limits> |
+ |
+#include "base/logging.h" |
+#include "base/numerics/safe_conversions.h" |
+ |
+namespace crashpad { |
+ |
+DelimitedFileReader::DelimitedFileReader(FileReaderInterface* file_reader) |
+ : file_reader_(file_reader), buf_pos_(0), buf_len_(0), eof_(false) { |
+ static_assert(sizeof(buf_) <= std::numeric_limits<decltype(buf_pos_)>::max(), |
+ "buf_pos_ must cover buf_"); |
+ static_assert(sizeof(buf_) <= std::numeric_limits<decltype(buf_len_)>::max(), |
+ "buf_len_ must cover buf_"); |
+} |
+ |
+DelimitedFileReader::~DelimitedFileReader() {} |
+ |
+DelimitedFileReader::Result DelimitedFileReader::GetDelim(char delimiter, |
+ std::string* field) { |
+ if (eof_) { |
+ DCHECK_EQ(buf_pos_, buf_len_); |
+ |
+ // Allow subsequent calls to attempt to read more data from the file. If the |
+ // file is still at EOF in the future, the read will return 0 and cause |
+ // kEndOfFile to be returned anyway. |
+ eof_ = false; |
+ |
+ return Result::kEndOfFile; |
+ } |
+ |
+ std::string local_field; |
+ while (true) { |
+ if (buf_pos_ == buf_len_) { |
+ // buf_ is empty. Refill it. |
+ FileOperationResult read_result = file_reader_->Read(buf_, sizeof(buf_)); |
+ if (read_result < 0) { |
+ return Result::kError; |
+ } else if (read_result == 0) { |
+ if (!local_field.empty()) { |
+ // The file ended with a field that wasn’t terminated by a delimiter |
+ // character. |
+ // |
+ // This is EOF, but EOF can’t be returned because there’s a field that |
+ // needs to be returned to the caller. Cache the detected EOF so it |
+ // can be returned next time. This is done to support proper semantics |
+ // for weird “files” like terminal input that can reach EOF and then |
+ // “grow”, allowing subsequent reads past EOF to block while waiting |
+ // for more data. Once EOF is detected by a read that returns 0, that |
+ // EOF signal should propagate to the caller before attempting a new |
+ // read. Here, it will be returned on the next call to this method |
+ // without attempting to read more data. |
+ eof_ = true; |
+ field->swap(local_field); |
+ return Result::kSuccess; |
+ } |
+ return Result::kEndOfFile; |
+ } |
+ |
+ DCHECK_LE(static_cast<size_t>(read_result), arraysize(buf_)); |
+ DCHECK( |
+ base::IsValueInRangeForNumericType<decltype(buf_len_)>(read_result)); |
+ buf_len_ = static_cast<decltype(buf_len_)>(read_result); |
+ buf_pos_ = 0; |
+ } |
+ |
+ const char* const start = buf_ + buf_pos_; |
+ const char* const end = buf_ + buf_len_; |
+ const char* const found = std::find(start, end, delimiter); |
+ |
+ local_field.append(start, found); |
+ buf_pos_ = static_cast<decltype(buf_pos_)>(found - buf_); |
+ DCHECK_LE(buf_pos_, buf_len_); |
+ |
+ if (found != end) { |
+ // A real delimiter character was found. Append it to the field being |
+ // built and return it. |
+ local_field.push_back(delimiter); |
+ ++buf_pos_; |
+ DCHECK_LE(buf_pos_, buf_len_); |
+ field->swap(local_field); |
+ return Result::kSuccess; |
+ } |
+ } |
+} |
+ |
+DelimitedFileReader::Result DelimitedFileReader::GetLine(std::string* line) { |
+ return GetDelim('\n', line); |
+} |
+ |
+} // namespace crashpad |