1 /* 2 * 3 * Copyright 2015 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 #include <grpc/support/port_platform.h> 20 21 #include "src/core/ext/filters/client_channel/lb_policy_registry.h" 22 23 #include <string.h> 24 25 #include "src/core/lib/gpr/string.h" 26 #include "src/core/lib/gprpp/inlined_vector.h" 27 28 namespace grpc_core { 29 30 namespace { 31 32 class RegistryState { 33 public: RegistryState()34 RegistryState() {} 35 RegisterLoadBalancingPolicyFactory(UniquePtr<LoadBalancingPolicyFactory> factory)36 void RegisterLoadBalancingPolicyFactory( 37 UniquePtr<LoadBalancingPolicyFactory> factory) { 38 for (size_t i = 0; i < factories_.size(); ++i) { 39 GPR_ASSERT(strcmp(factories_[i]->name(), factory->name()) != 0); 40 } 41 factories_.push_back(std::move(factory)); 42 } 43 GetLoadBalancingPolicyFactory(const char * name) const44 LoadBalancingPolicyFactory* GetLoadBalancingPolicyFactory( 45 const char* name) const { 46 for (size_t i = 0; i < factories_.size(); ++i) { 47 if (strcmp(name, factories_[i]->name()) == 0) { 48 return factories_[i].get(); 49 } 50 } 51 return nullptr; 52 } 53 54 private: 55 InlinedVector<UniquePtr<LoadBalancingPolicyFactory>, 10> factories_; 56 }; 57 58 RegistryState* g_state = nullptr; 59 60 } // namespace 61 62 // 63 // LoadBalancingPolicyRegistry::Builder 64 // 65 InitRegistry()66void LoadBalancingPolicyRegistry::Builder::InitRegistry() { 67 if (g_state == nullptr) g_state = New<RegistryState>(); 68 } 69 ShutdownRegistry()70void LoadBalancingPolicyRegistry::Builder::ShutdownRegistry() { 71 Delete(g_state); 72 g_state = nullptr; 73 } 74 RegisterLoadBalancingPolicyFactory(UniquePtr<LoadBalancingPolicyFactory> factory)75void LoadBalancingPolicyRegistry::Builder::RegisterLoadBalancingPolicyFactory( 76 UniquePtr<LoadBalancingPolicyFactory> factory) { 77 InitRegistry(); 78 g_state->RegisterLoadBalancingPolicyFactory(std::move(factory)); 79 } 80 81 // 82 // LoadBalancingPolicyRegistry 83 // 84 85 OrphanablePtr<LoadBalancingPolicy> CreateLoadBalancingPolicy(const char * name,const LoadBalancingPolicy::Args & args)86LoadBalancingPolicyRegistry::CreateLoadBalancingPolicy( 87 const char* name, const LoadBalancingPolicy::Args& args) { 88 GPR_ASSERT(g_state != nullptr); 89 // Find factory. 90 LoadBalancingPolicyFactory* factory = 91 g_state->GetLoadBalancingPolicyFactory(name); 92 if (factory == nullptr) return nullptr; // Specified name not found. 93 // Create policy via factory. 94 return factory->CreateLoadBalancingPolicy(args); 95 } 96 97 } // namespace grpc_core 98