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// Copyright 2017 The Chromium 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 "base/metrics/field_trial_params.h"
#include "base/feature_list.h"
#include "base/metrics/field_trial.h"
#include "base/metrics/field_trial_param_associator.h"
#include "base/strings/string_number_conversions.h"
namespace base {
bool AssociateFieldTrialParams(
const std::string& trial_name,
const std::string& group_name,
const std::map<std::string, std::string>& params) {
return base::FieldTrialParamAssociator::GetInstance()
->AssociateFieldTrialParams(trial_name, group_name, params);
}
bool GetFieldTrialParams(const std::string& trial_name,
std::map<std::string, std::string>* params) {
return base::FieldTrialParamAssociator::GetInstance()->GetFieldTrialParams(
trial_name, params);
}
bool GetFieldTrialParamsByFeature(const base::Feature& feature,
std::map<std::string, std::string>* params) {
if (!base::FeatureList::IsEnabled(feature))
return false;
base::FieldTrial* trial = base::FeatureList::GetFieldTrial(feature);
if (!trial)
return false;
return GetFieldTrialParams(trial->trial_name(), params);
}
std::string GetFieldTrialParamValue(const std::string& trial_name,
const std::string& param_name) {
std::map<std::string, std::string> params;
if (GetFieldTrialParams(trial_name, ¶ms)) {
std::map<std::string, std::string>::iterator it = params.find(param_name);
if (it != params.end())
return it->second;
}
return std::string();
}
std::string GetFieldTrialParamValueByFeature(const base::Feature& feature,
const std::string& param_name) {
if (!base::FeatureList::IsEnabled(feature))
return std::string();
base::FieldTrial* trial = base::FeatureList::GetFieldTrial(feature);
if (!trial)
return std::string();
return GetFieldTrialParamValue(trial->trial_name(), param_name);
}
int GetFieldTrialParamByFeatureAsInt(const base::Feature& feature,
const std::string& param_name,
int default_value) {
std::string value_as_string =
GetFieldTrialParamValueByFeature(feature, param_name);
int value_as_int = 0;
if (!base::StringToInt(value_as_string, &value_as_int)) {
if (!value_as_string.empty()) {
DLOG(WARNING) << "Failed to parse field trial param " << param_name
<< " with string value " << value_as_string
<< " under feature " << feature.name
<< " into an int. Falling back to default value of "
<< default_value;
}
value_as_int = default_value;
}
return value_as_int;
}
double GetFieldTrialParamByFeatureAsDouble(const base::Feature& feature,
const std::string& param_name,
double default_value) {
std::string value_as_string =
GetFieldTrialParamValueByFeature(feature, param_name);
double value_as_double = 0;
if (!base::StringToDouble(value_as_string, &value_as_double)) {
if (!value_as_string.empty()) {
DLOG(WARNING) << "Failed to parse field trial param " << param_name
<< " with string value " << value_as_string
<< " under feature " << feature.name
<< " into a double. Falling back to default value of "
<< default_value;
}
value_as_double = default_value;
}
return value_as_double;
}
bool GetFieldTrialParamByFeatureAsBool(const base::Feature& feature,
const std::string& param_name,
bool default_value) {
std::string value_as_string =
GetFieldTrialParamValueByFeature(feature, param_name);
if (value_as_string == "true")
return true;
if (value_as_string == "false")
return false;
if (!value_as_string.empty()) {
DLOG(WARNING) << "Failed to parse field trial param " << param_name
<< " with string value " << value_as_string
<< " under feature " << feature.name
<< " into a bool. Falling back to default value of "
<< default_value;
}
return default_value;
}
std::string FeatureParam<std::string>::Get() const {
const std::string value = GetFieldTrialParamValueByFeature(*feature, name);
return value.empty() ? default_value : value;
}
double FeatureParam<double>::Get() const {
return GetFieldTrialParamByFeatureAsDouble(*feature, name, default_value);
}
int FeatureParam<int>::Get() const {
return GetFieldTrialParamByFeatureAsInt(*feature, name, default_value);
}
bool FeatureParam<bool>::Get() const {
return GetFieldTrialParamByFeatureAsBool(*feature, name, default_value);
}
void LogInvalidEnumValue(const base::Feature& feature,
const std::string& param_name,
const std::string& value_as_string,
int default_value_as_int) {
DLOG(WARNING) << "Failed to parse field trial param " << param_name
<< " with string value " << value_as_string << " under feature "
<< feature.name
<< " into an enum. Falling back to default value of "
<< default_value_as_int;
}
} // namespace base
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