legacy-libs/grpc-cloned/deps/grpc/src/core/ext/filters/client_channel/subchannel_pool_interface.cc

   1 //
   2 //
   3 // Copyright 2018 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/subchannel_pool_interface.h"
  22
  23 #include "src/core/lib/gpr/useful.h"
  24
  25 // The subchannel pool to reuse subchannels.
  26 #define GRPC_ARG_SUBCHANNEL_POOL "grpc.subchannel_pool"
  27 // The subchannel key ID that is only used in test to make each key unique.
  28 #define GRPC_ARG_SUBCHANNEL_KEY_TEST_ONLY_ID "grpc.subchannel_key_test_only_id"
  29
  30 namespace grpc_core {
  31
  32 TraceFlag grpc_subchannel_pool_trace(false, "subchannel_pool");
  33
  34 SubchannelKey::SubchannelKey(const grpc_channel_args* args) {
  35   Init(args, grpc_channel_args_normalize);
  36 }
  37
  38 SubchannelKey::~SubchannelKey() {
  39   grpc_channel_args_destroy(const_cast<grpc_channel_args*>(args_));
  40 }
  41
  42 SubchannelKey::SubchannelKey(const SubchannelKey& other) {
  43   Init(other.args_, grpc_channel_args_copy);
  44 }
  45
  46 SubchannelKey& SubchannelKey::operator=(const SubchannelKey& other) {
  47   grpc_channel_args_destroy(const_cast<grpc_channel_args*>(args_));
  48   Init(other.args_, grpc_channel_args_copy);
  49   return *this;
  50 }
  51
  52 int SubchannelKey::Cmp(const SubchannelKey& other) const {
  53   return grpc_channel_args_compare(args_, other.args_);
  54 }
  55
  56 void SubchannelKey::Init(
  57     const grpc_channel_args* args,
  58     grpc_channel_args* (*copy_channel_args)(const grpc_channel_args* args)) {
  59   args_ = copy_channel_args(args);
  60 }
  61
  62 namespace {
  63
  64 void* arg_copy(void* p) {
  65   auto* subchannel_pool = static_cast<SubchannelPoolInterface*>(p);
  66   subchannel_pool->Ref().release();
  67   return p;
  68 }
  69
  70 void arg_destroy(void* p) {
  71   auto* subchannel_pool = static_cast<SubchannelPoolInterface*>(p);
  72   subchannel_pool->Unref();
  73 }
  74
  75 int arg_cmp(void* a, void* b) { return GPR_ICMP(a, b); }
  76
  77 const grpc_arg_pointer_vtable subchannel_pool_arg_vtable = {
  78     arg_copy, arg_destroy, arg_cmp};
  79
  80 }  // namespace
  81
  82 grpc_arg SubchannelPoolInterface::CreateChannelArg(
  83     SubchannelPoolInterface* subchannel_pool) {
  84   return grpc_channel_arg_pointer_create(
  85       const_cast<char*>(GRPC_ARG_SUBCHANNEL_POOL), subchannel_pool,
  86       &subchannel_pool_arg_vtable);
  87 }
  88
  89 SubchannelPoolInterface*
  90 SubchannelPoolInterface::GetSubchannelPoolFromChannelArgs(
  91     const grpc_channel_args* args) {
  92   const grpc_arg* arg = grpc_channel_args_find(args, GRPC_ARG_SUBCHANNEL_POOL);
  93   if (arg == nullptr || arg->type != GRPC_ARG_POINTER) return nullptr;
  94   return static_cast<SubchannelPoolInterface*>(arg->value.pointer.p);
  95 }
  96
  97 }  // namespace grpc_core