1 files changed, 85 insertions, 0 deletions
diff --git a/third_party/libwebrtc/api/rtc_event_log_output_file.cc b/third_party/libwebrtc/api/rtc_event_log_output_file.cc
new file mode 100644
index 0000000000..e1d4c7c711
--- /dev/null
+++ b/third_party/libwebrtc/api/rtc_event_log_output_file.cc
@@ -0,0 +1,85 @@
+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "api/rtc_event_log_output_file.h"
+
+#include <limits>
+#include <utility>
+
+#include "api/rtc_event_log/rtc_event_log.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+
+namespace webrtc {
+
+// Together with the assumption of no single Write() would ever be called on
+// an input with length greater-than-or-equal-to (max(size_t) / 2), this
+// guarantees no overflow of the check for remaining file capacity in Write().
+// This does *not* apply to files with unlimited size.
+const size_t RtcEventLogOutputFile::kMaxReasonableFileSize =
+    std::numeric_limits<size_t>::max() / 2;
+
+RtcEventLogOutputFile::RtcEventLogOutputFile(const std::string& file_name)
+    : RtcEventLogOutputFile(FileWrapper::OpenWriteOnly(file_name),
+                            RtcEventLog::kUnlimitedOutput) {}
+
+RtcEventLogOutputFile::RtcEventLogOutputFile(const std::string& file_name,
+                                             size_t max_size_bytes)
+
+    // Unlike plain fopen, FileWrapper takes care of filename utf8 ->
+    // wchar conversion on Windows.
+    : RtcEventLogOutputFile(FileWrapper::OpenWriteOnly(file_name),
+                            max_size_bytes) {}
+
+RtcEventLogOutputFile::RtcEventLogOutputFile(FILE* file, size_t max_size_bytes)
+    : RtcEventLogOutputFile(FileWrapper(file), max_size_bytes) {}
+
+RtcEventLogOutputFile::RtcEventLogOutputFile(FileWrapper file,
+                                             size_t max_size_bytes)
+    : max_size_bytes_(max_size_bytes), file_(std::move(file)) {
+  RTC_CHECK_LE(max_size_bytes_, kMaxReasonableFileSize);
+  if (!file_.is_open()) {
+    RTC_LOG(LS_ERROR) << "Invalid file. WebRTC event log not started.";
+  }
+}
+
+bool RtcEventLogOutputFile::IsActive() const {
+  return IsActiveInternal();
+}
+
+bool RtcEventLogOutputFile::Write(absl::string_view output) {
+  RTC_DCHECK(IsActiveInternal());
+  // No single write may be so big, that it would risk overflowing the
+  // calculation of (written_bytes_ + output.length()).
+  RTC_DCHECK_LT(output.size(), kMaxReasonableFileSize);
+
+  if (max_size_bytes_ == RtcEventLog::kUnlimitedOutput ||
+      written_bytes_ + output.size() <= max_size_bytes_) {
+    if (file_.Write(output.data(), output.size())) {
+      written_bytes_ += output.size();
+      return true;
+    } else {
+      RTC_LOG(LS_ERROR) << "Write to WebRtcEventLog file failed.";
+    }
+  } else {
+    RTC_LOG(LS_VERBOSE) << "Max file size reached.";
+  }
+
+  // Failed, for one of above reasons. Close output file.
+  file_.Close();
+  return false;
+}
+
+// Internal non-virtual method.
+bool RtcEventLogOutputFile::IsActiveInternal() const {
+  return file_.is_open();
+}
+
+}  // namespace webrtc