1 files changed, 93 insertions, 0 deletions
diff --git a/third_party/libwebrtc/webrtc/test/field_trial.cc b/third_party/libwebrtc/webrtc/test/field_trial.cc
new file mode 100644
index 0000000000..00e5b69041
--- /dev/null
+++ b/third_party/libwebrtc/webrtc/test/field_trial.cc
@@ -0,0 +1,93 @@
+/*
+ *  Copyright (c) 2014 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 "test/field_trial.h"
+
+#include <algorithm>
+#include <cassert>
+#include <cstdio>
+#include <cstdlib>
+#include <map>
+#include <string>
+
+#include "system_wrappers/include/field_trial.h"
+#include "system_wrappers/include/field_trial_default.h"
+
+namespace webrtc {
+namespace {
+bool field_trials_initiated_ = false;
+}  // namespace
+
+namespace test {
+// Note: this code is copied from src/base/metrics/field_trial.cc since the aim
+// is to mimic chromium --force-fieldtrials.
+void InitFieldTrialsFromString(const std::string& trials_string) {
+  static const char kPersistentStringSeparator = '/';
+
+  // Catch an error if this is called more than once.
+  assert(!field_trials_initiated_);
+  field_trials_initiated_ = true;
+
+  if (trials_string.empty())
+    return;
+
+  size_t next_item = 0;
+  std::map<std::string, std::string> field_trials;
+  while (next_item < trials_string.length()) {
+    size_t name_end = trials_string.find(kPersistentStringSeparator, next_item);
+    if (name_end == trials_string.npos || next_item == name_end)
+      break;
+    size_t group_name_end = trials_string.find(kPersistentStringSeparator,
+                                               name_end + 1);
+    if (group_name_end == trials_string.npos || name_end + 1 == group_name_end)
+      break;
+    std::string name(trials_string, next_item, name_end - next_item);
+    std::string group_name(trials_string, name_end + 1,
+                           group_name_end - name_end - 1);
+    next_item = group_name_end + 1;
+
+    // Fail if duplicate with different group name.
+    if (field_trials.find(name) != field_trials.end() &&
+        field_trials.find(name)->second != group_name) {
+      break;
+    }
+
+    field_trials[name] = group_name;
+
+    // Successfully parsed all field trials from the string.
+    if (next_item == trials_string.length()) {
+      webrtc::field_trial::InitFieldTrialsFromString(trials_string.c_str());
+      return;
+    }
+  }
+  // Using fprintf as RTC_LOG does not print when this is called early in main.
+  fprintf(stderr, "Invalid field trials string.\n");
+
+  // Using abort so it crashes in both debug and release mode.
+  abort();
+}
+
+ScopedFieldTrials::ScopedFieldTrials(const std::string& config)
+  : previous_field_trials_(webrtc::field_trial::GetFieldTrialString()) {
+  assert(field_trials_initiated_);
+  field_trials_initiated_ = false;
+  current_field_trials_ = config;
+  InitFieldTrialsFromString(current_field_trials_);
+}
+
+ScopedFieldTrials::~ScopedFieldTrials() {
+  // Should still be initialized, since InitFieldTrials is called from ctor.
+  // That's why we don't restore the flag.
+  assert(field_trials_initiated_);
+  webrtc::field_trial::InitFieldTrialsFromString(previous_field_trials_);
+}
+
+}  // namespace test
+}  // namespace webrtc