deprecated_global_field_trials.cc (1903B)
1 /* 2 * Copyright 2019 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 #include "api/environment/deprecated_global_field_trials.h" 11 12 #include <cstddef> 13 #include <string> 14 15 #include "absl/strings/string_view.h" 16 17 namespace webrtc { 18 namespace { 19 20 constinit const char* global_field_trial_string = nullptr; 21 22 } // namespace 23 24 void DeprecatedGlobalFieldTrials::Set(const char* field_trials) { 25 global_field_trial_string = field_trials; 26 } 27 28 std::string DeprecatedGlobalFieldTrials::GetValue(absl::string_view key) const { 29 if (global_field_trial_string == nullptr) 30 return std::string(); 31 32 absl::string_view trials_string(global_field_trial_string); 33 if (trials_string.empty()) 34 return std::string(); 35 36 size_t next_item = 0; 37 while (next_item < trials_string.length()) { 38 // Find next name/value pair in field trial configuration string. 39 size_t field_name_end = trials_string.find('/', next_item); 40 if (field_name_end == trials_string.npos || field_name_end == next_item) 41 break; 42 size_t field_value_end = trials_string.find('/', field_name_end + 1); 43 if (field_value_end == trials_string.npos || 44 field_value_end == field_name_end + 1) 45 break; 46 absl::string_view field_name = 47 trials_string.substr(next_item, field_name_end - next_item); 48 absl::string_view field_value = trials_string.substr( 49 field_name_end + 1, field_value_end - field_name_end - 1); 50 next_item = field_value_end + 1; 51 52 if (key == field_name) 53 return std::string(field_value); 54 } 55 return std::string(); 56 } 57 } // namespace webrtc