| /* |
| * |
| * Copyright 2016 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H |
| #define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include <ares.h> |
| #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h" |
| #include "src/core/lib/gprpp/abstract.h" |
| #include "src/core/lib/iomgr/pollset_set.h" |
| |
| typedef struct grpc_ares_ev_driver grpc_ares_ev_driver; |
| |
| /* Start \a ev_driver. It will keep working until all IO on its ares_channel is |
| done, or grpc_ares_ev_driver_destroy() is called. It may notify the callbacks |
| bound to its ares_channel when necessary. */ |
| void grpc_ares_ev_driver_start_locked(grpc_ares_ev_driver* ev_driver); |
| |
| /* Returns the ares_channel owned by \a ev_driver. To bind a c-ares query to |
| \a ev_driver, use the ares_channel owned by \a ev_driver as the arg of the |
| query. */ |
| ares_channel* grpc_ares_ev_driver_get_channel_locked( |
| grpc_ares_ev_driver* ev_driver); |
| |
| /* Creates a new grpc_ares_ev_driver. Returns GRPC_ERROR_NONE if \a ev_driver is |
| created successfully. */ |
| grpc_error* grpc_ares_ev_driver_create_locked(grpc_ares_ev_driver** ev_driver, |
| grpc_pollset_set* pollset_set, |
| int query_timeout_ms, |
| grpc_combiner* combiner, |
| grpc_ares_request* request); |
| |
| /* Called back when all DNS lookups have completed. */ |
| void grpc_ares_ev_driver_on_queries_complete_locked( |
| grpc_ares_ev_driver* ev_driver); |
| |
| /* Shutdown all the grpc_fds used by \a ev_driver */ |
| void grpc_ares_ev_driver_shutdown_locked(grpc_ares_ev_driver* ev_driver); |
| |
| namespace grpc_core { |
| |
| /* A wrapped fd that integrates with the grpc iomgr of the current platform. |
| * A GrpcPolledFd knows how to create grpc platform-specific iomgr endpoints |
| * from "ares_socket_t" sockets, and then sign up for readability/writeability |
| * with that poller, and do shutdown and destruction. */ |
| class GrpcPolledFd { |
| public: |
| virtual ~GrpcPolledFd() {} |
| /* Called when c-ares library is interested and there's no pending callback */ |
| virtual void RegisterForOnReadableLocked(grpc_closure* read_closure) |
| GRPC_ABSTRACT; |
| /* Called when c-ares library is interested and there's no pending callback */ |
| virtual void RegisterForOnWriteableLocked(grpc_closure* write_closure) |
| GRPC_ABSTRACT; |
| /* Indicates if there is data left even after just being read from */ |
| virtual bool IsFdStillReadableLocked() GRPC_ABSTRACT; |
| /* Called once and only once. Must cause cancellation of any pending |
| * read/write callbacks. */ |
| virtual void ShutdownLocked(grpc_error* error) GRPC_ABSTRACT; |
| /* Get the underlying ares_socket_t that this was created from */ |
| virtual ares_socket_t GetWrappedAresSocketLocked() GRPC_ABSTRACT; |
| /* A unique name, for logging */ |
| virtual const char* GetName() GRPC_ABSTRACT; |
| |
| GRPC_ABSTRACT_BASE_CLASS |
| }; |
| |
| /* A GrpcPolledFdFactory is 1-to-1 with and owned by the |
| * ares event driver. It knows how to create GrpcPolledFd's |
| * for the current platform, and the ares driver uses it for all of |
| * its fd's. */ |
| class GrpcPolledFdFactory { |
| public: |
| virtual ~GrpcPolledFdFactory() {} |
| /* Creates a new wrapped fd for the current platform */ |
| virtual GrpcPolledFd* NewGrpcPolledFdLocked( |
| ares_socket_t as, grpc_pollset_set* driver_pollset_set, |
| grpc_combiner* combiner) GRPC_ABSTRACT; |
| /* Optionally configures the ares channel after creation */ |
| virtual void ConfigureAresChannelLocked(ares_channel channel) GRPC_ABSTRACT; |
| |
| GRPC_ABSTRACT_BASE_CLASS |
| }; |
| |
| UniquePtr<GrpcPolledFdFactory> NewGrpcPolledFdFactory(grpc_combiner* combiner); |
| |
| } // namespace grpc_core |
| |
| #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H \ |
| */ |