Adds enum field trial parser.
Removed the need to create a custom parser function and reuses some of
the code to reduce binary overhead of enums.
Bug: webrtc:9346
Change-Id: I51c9da713ed5456a86a2afbcf0991477bb83b894
Reviewed-on: https://webrtc-review.googlesource.com/83623
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23752}diff --git a/rtc_base/experiments/field_trial_parser.h b/rtc_base/experiments/field_trial_parser.h
index ff00b90..a385ccf 100644
--- a/rtc_base/experiments/field_trial_parser.h
+++ b/rtc_base/experiments/field_trial_parser.h
@@ -12,6 +12,8 @@
#include <stdint.h>
#include <initializer_list>
+#include <map>
+#include <set>
#include <string>
#include "absl/types/optional.h"
@@ -83,6 +85,47 @@
T value_;
};
+class AbstractFieldTrialEnum : public FieldTrialParameterInterface {
+ public:
+ AbstractFieldTrialEnum(std::string key,
+ int default_value,
+ std::map<std::string, int> mapping);
+ ~AbstractFieldTrialEnum() override;
+ AbstractFieldTrialEnum(const AbstractFieldTrialEnum&);
+
+ protected:
+ bool Parse(absl::optional<std::string> str_value) override;
+
+ protected:
+ int value_;
+ std::map<std::string, int> enum_mapping_;
+ std::set<int> valid_values_;
+};
+
+// The FieldTrialEnum class can be used to quickly define a parser for a
+// specific enum. It handles values provided as integers and as strings if a
+// mapping is provided.
+template <typename T>
+class FieldTrialEnum : public AbstractFieldTrialEnum {
+ public:
+ FieldTrialEnum(std::string key,
+ T default_value,
+ std::map<std::string, T> mapping)
+ : AbstractFieldTrialEnum(key,
+ static_cast<int>(default_value),
+ ToIntMap(mapping)) {}
+ T Get() const { return static_cast<T>(value_); }
+ operator T() const { return Get(); }
+
+ private:
+ static std::map<std::string, int> ToIntMap(std::map<std::string, T> mapping) {
+ std::map<std::string, int> res;
+ for (const auto& it : mapping)
+ res[it.first] = static_cast<int>(it.second);
+ return res;
+ }
+};
+
// This class uses the ParseTypedParameter function to implement an optional
// parameter implementation that can default to absl::nullopt.
template <typename T>