| /* |
| * |
| * Copyright 2015 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_LIB_TRANSPORT_TRANSPORT_H |
| #define GRPC_CORE_LIB_TRANSPORT_TRANSPORT_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include <stddef.h> |
| |
| #include "src/core/lib/channel/context.h" |
| #include "src/core/lib/gpr/arena.h" |
| #include "src/core/lib/iomgr/call_combiner.h" |
| #include "src/core/lib/iomgr/endpoint.h" |
| #include "src/core/lib/iomgr/polling_entity.h" |
| #include "src/core/lib/iomgr/pollset.h" |
| #include "src/core/lib/iomgr/pollset_set.h" |
| #include "src/core/lib/transport/byte_stream.h" |
| #include "src/core/lib/transport/metadata_batch.h" |
| |
| /* Minimum and maximum protocol accepted versions. */ |
| #define GRPC_PROTOCOL_VERSION_MAX_MAJOR 2 |
| #define GRPC_PROTOCOL_VERSION_MAX_MINOR 1 |
| #define GRPC_PROTOCOL_VERSION_MIN_MAJOR 2 |
| #define GRPC_PROTOCOL_VERSION_MIN_MINOR 1 |
| |
| /* forward declarations */ |
| |
| typedef struct grpc_transport grpc_transport; |
| |
| /* grpc_stream doesn't actually exist. It's used as a typesafe |
| opaque pointer for whatever data the transport wants to track |
| for a stream. */ |
| typedef struct grpc_stream grpc_stream; |
| |
| extern grpc_core::DebugOnlyTraceFlag grpc_trace_stream_refcount; |
| |
| typedef struct grpc_stream_refcount { |
| gpr_refcount refs; |
| grpc_closure destroy; |
| #ifndef NDEBUG |
| const char* object_type; |
| #endif |
| grpc_slice_refcount slice_refcount; |
| } grpc_stream_refcount; |
| |
| #ifndef NDEBUG |
| void grpc_stream_ref_init(grpc_stream_refcount* refcount, int initial_refs, |
| grpc_iomgr_cb_func cb, void* cb_arg, |
| const char* object_type); |
| void grpc_stream_ref(grpc_stream_refcount* refcount, const char* reason); |
| void grpc_stream_unref(grpc_stream_refcount* refcount, const char* reason); |
| #define GRPC_STREAM_REF_INIT(rc, ir, cb, cb_arg, objtype) \ |
| grpc_stream_ref_init(rc, ir, cb, cb_arg, objtype) |
| #else |
| void grpc_stream_ref_init(grpc_stream_refcount* refcount, int initial_refs, |
| grpc_iomgr_cb_func cb, void* cb_arg); |
| void grpc_stream_ref(grpc_stream_refcount* refcount); |
| void grpc_stream_unref(grpc_stream_refcount* refcount); |
| #define GRPC_STREAM_REF_INIT(rc, ir, cb, cb_arg, objtype) \ |
| grpc_stream_ref_init(rc, ir, cb, cb_arg) |
| #endif |
| |
| /* Wrap a buffer that is owned by some stream object into a slice that shares |
| the same refcount */ |
| grpc_slice grpc_slice_from_stream_owned_buffer(grpc_stream_refcount* refcount, |
| void* buffer, size_t length); |
| |
| struct grpc_transport_one_way_stats { |
| uint64_t framing_bytes = 0; |
| uint64_t data_bytes = 0; |
| uint64_t header_bytes = 0; |
| }; |
| |
| struct grpc_transport_stream_stats { |
| grpc_transport_one_way_stats incoming; |
| grpc_transport_one_way_stats outgoing; |
| }; |
| |
| void grpc_transport_move_one_way_stats(grpc_transport_one_way_stats* from, |
| grpc_transport_one_way_stats* to); |
| |
| void grpc_transport_move_stats(grpc_transport_stream_stats* from, |
| grpc_transport_stream_stats* to); |
| |
| // This struct (which is present in both grpc_transport_stream_op_batch |
| // and grpc_transport_op_batch) is a convenience to allow filters or |
| // transports to schedule a closure related to a particular batch without |
| // having to allocate memory. The general pattern is to initialize the |
| // closure with the callback arg set to the batch and extra_arg set to |
| // whatever state is associated with the handler (e.g., the call element |
| // or the transport stream object). |
| // |
| // Note that this can only be used by the current handler of a given |
| // batch on the way down the stack (i.e., whichever filter or transport is |
| // currently handling the batch). Once a filter or transport passes control |
| // of the batch to the next handler, it cannot depend on the contents of |
| // this struct anymore, because the next handler may reuse it. |
| typedef struct { |
| void* extra_arg; |
| grpc_closure closure; |
| } grpc_handler_private_op_data; |
| |
| typedef struct grpc_transport_stream_op_batch_payload |
| grpc_transport_stream_op_batch_payload; |
| |
| /* Transport stream op: a set of operations to perform on a transport |
| against a single stream */ |
| struct grpc_transport_stream_op_batch { |
| grpc_transport_stream_op_batch() |
| : send_initial_metadata(false), |
| send_trailing_metadata(false), |
| send_message(false), |
| recv_initial_metadata(false), |
| recv_message(false), |
| recv_trailing_metadata(false), |
| cancel_stream(false), |
| is_traced(false) {} |
| |
| /** Should be scheduled when all of the non-recv operations in the batch |
| are complete. |
| |
| The recv ops (recv_initial_metadata, recv_message, and |
| recv_trailing_metadata) each have their own callbacks. If a batch |
| contains both recv ops and non-recv ops, on_complete should be |
| scheduled as soon as the non-recv ops are complete, regardless of |
| whether or not the recv ops are complete. If a batch contains |
| only recv ops, on_complete can be null. */ |
| grpc_closure* on_complete = nullptr; |
| |
| /** Values for the stream op (fields set are determined by flags above) */ |
| grpc_transport_stream_op_batch_payload* payload = nullptr; |
| |
| /** Send initial metadata to the peer, from the provided metadata batch. */ |
| bool send_initial_metadata : 1; |
| |
| /** Send trailing metadata to the peer, from the provided metadata batch. */ |
| bool send_trailing_metadata : 1; |
| |
| /** Send message data to the peer, from the provided byte stream. */ |
| bool send_message : 1; |
| |
| /** Receive initial metadata from the stream, into provided metadata batch. */ |
| bool recv_initial_metadata : 1; |
| |
| /** Receive message data from the stream, into provided byte stream. */ |
| bool recv_message : 1; |
| |
| /** Receive trailing metadata from the stream, into provided metadata batch. |
| */ |
| bool recv_trailing_metadata : 1; |
| |
| /** Cancel this stream with the provided error */ |
| bool cancel_stream : 1; |
| |
| /** Is this stream traced */ |
| bool is_traced : 1; |
| |
| /*************************************************************************** |
| * remaining fields are initialized and used at the discretion of the |
| * current handler of the op */ |
| |
| grpc_handler_private_op_data handler_private; |
| }; |
| |
| struct grpc_transport_stream_op_batch_payload { |
| explicit grpc_transport_stream_op_batch_payload( |
| grpc_call_context_element* context) |
| : context(context) {} |
| ~grpc_transport_stream_op_batch_payload() { |
| // We don't really own `send_message`, so release ownership and let the |
| // owner clean the data. |
| send_message.send_message.release(); |
| } |
| |
| struct { |
| grpc_metadata_batch* send_initial_metadata = nullptr; |
| /** Iff send_initial_metadata != NULL, flags associated with |
| send_initial_metadata: a bitfield of GRPC_INITIAL_METADATA_xxx */ |
| uint32_t send_initial_metadata_flags = 0; |
| // If non-NULL, will be set by the transport to the peer string (a char*). |
| // The transport retains ownership of the string. |
| // Note: This pointer may be used by the transport after the |
| // send_initial_metadata op is completed. It must remain valid |
| // until the call is destroyed. |
| gpr_atm* peer_string = nullptr; |
| } send_initial_metadata; |
| |
| struct { |
| grpc_metadata_batch* send_trailing_metadata = nullptr; |
| } send_trailing_metadata; |
| |
| struct { |
| // The transport (or a filter that decides to return a failure before |
| // the op gets down to the transport) takes ownership. |
| // The batch's on_complete will not be called until after the byte |
| // stream is orphaned. |
| grpc_core::OrphanablePtr<grpc_core::ByteStream> send_message; |
| } send_message; |
| |
| struct { |
| grpc_metadata_batch* recv_initial_metadata = nullptr; |
| // Flags are used only on the server side. If non-null, will be set to |
| // a bitfield of the GRPC_INITIAL_METADATA_xxx macros (e.g., to |
| // indicate if the call is idempotent). |
| uint32_t* recv_flags = nullptr; |
| /** Should be enqueued when initial metadata is ready to be processed. */ |
| grpc_closure* recv_initial_metadata_ready = nullptr; |
| // If not NULL, will be set to true if trailing metadata is |
| // immediately available. This may be a signal that we received a |
| // Trailers-Only response. |
| bool* trailing_metadata_available = nullptr; |
| // If non-NULL, will be set by the transport to the peer string (a char*). |
| // The transport retains ownership of the string. |
| // Note: This pointer may be used by the transport after the |
| // recv_initial_metadata op is completed. It must remain valid |
| // until the call is destroyed. |
| gpr_atm* peer_string = nullptr; |
| } recv_initial_metadata; |
| |
| struct { |
| // Will be set by the transport to point to the byte stream |
| // containing a received message. |
| // Will be NULL if trailing metadata is received instead of a message. |
| grpc_core::OrphanablePtr<grpc_core::ByteStream>* recv_message = nullptr; |
| /** Should be enqueued when one message is ready to be processed. */ |
| grpc_closure* recv_message_ready = nullptr; |
| } recv_message; |
| |
| struct { |
| grpc_metadata_batch* recv_trailing_metadata = nullptr; |
| grpc_transport_stream_stats* collect_stats = nullptr; |
| /** Should be enqueued when initial metadata is ready to be processed. */ |
| grpc_closure* recv_trailing_metadata_ready = nullptr; |
| } recv_trailing_metadata; |
| |
| /** Forcefully close this stream. |
| The HTTP2 semantics should be: |
| - server side: if cancel_error has GRPC_ERROR_INT_GRPC_STATUS, and |
| trailing metadata has not been sent, send trailing metadata with status |
| and message from cancel_error (use grpc_error_get_status) followed by |
| a RST_STREAM with error=GRPC_CHTTP2_NO_ERROR to force a full close |
| - at all other times: use grpc_error_get_status to get a status code, and |
| convert to a HTTP2 error code using |
| grpc_chttp2_grpc_status_to_http2_error. Send a RST_STREAM with this |
| error. */ |
| struct { |
| // Error contract: the transport that gets this op must cause cancel_error |
| // to be unref'ed after processing it |
| grpc_error* cancel_error = GRPC_ERROR_NONE; |
| } cancel_stream; |
| |
| /* Indexes correspond to grpc_context_index enum values */ |
| grpc_call_context_element* context; |
| }; |
| |
| /** Transport op: a set of operations to perform on a transport as a whole */ |
| typedef struct grpc_transport_op { |
| /** Called when processing of this op is done. */ |
| grpc_closure* on_consumed; |
| /** connectivity monitoring - set connectivity_state to NULL to unsubscribe */ |
| grpc_closure* on_connectivity_state_change; |
| grpc_connectivity_state* connectivity_state; |
| /** should the transport be disconnected |
| * Error contract: the transport that gets this op must cause |
| * disconnect_with_error to be unref'ed after processing it */ |
| grpc_error* disconnect_with_error; |
| /** what should the goaway contain? |
| * Error contract: the transport that gets this op must cause |
| * goaway_error to be unref'ed after processing it */ |
| grpc_error* goaway_error; |
| /** set the callback for accepting new streams; |
| this is a permanent callback, unlike the other one-shot closures. |
| If true, the callback is set to set_accept_stream_fn, with its |
| user_data argument set to set_accept_stream_user_data */ |
| bool set_accept_stream; |
| void (*set_accept_stream_fn)(void* user_data, grpc_transport* transport, |
| const void* server_data); |
| void* set_accept_stream_user_data; |
| /** add this transport to a pollset */ |
| grpc_pollset* bind_pollset; |
| /** add this transport to a pollset_set */ |
| grpc_pollset_set* bind_pollset_set; |
| /** send a ping, if either on_initiate or on_ack is not NULL */ |
| struct { |
| /** Ping may be delayed by the transport, on_initiate callback will be |
| called when the ping is actually being sent. */ |
| grpc_closure* on_initiate; |
| /** Called when the ping ack is received */ |
| grpc_closure* on_ack; |
| } send_ping; |
| // If true, will reset the channel's connection backoff. |
| bool reset_connect_backoff; |
| |
| /*************************************************************************** |
| * remaining fields are initialized and used at the discretion of the |
| * transport implementation */ |
| |
| grpc_handler_private_op_data handler_private; |
| } grpc_transport_op; |
| |
| /* Returns the amount of memory required to store a grpc_stream for this |
| transport */ |
| size_t grpc_transport_stream_size(grpc_transport* transport); |
| |
| /* Initialize transport data for a stream. |
| |
| Returns 0 on success, any other (transport-defined) value for failure. |
| May assume that stream contains all-zeros. |
| |
| Arguments: |
| transport - the transport on which to create this stream |
| stream - a pointer to uninitialized memory to initialize |
| server_data - either NULL for a client initiated stream, or a pointer |
| supplied from the accept_stream callback function */ |
| int grpc_transport_init_stream(grpc_transport* transport, grpc_stream* stream, |
| grpc_stream_refcount* refcount, |
| const void* server_data, gpr_arena* arena); |
| |
| void grpc_transport_set_pops(grpc_transport* transport, grpc_stream* stream, |
| grpc_polling_entity* pollent); |
| |
| /* Destroy transport data for a stream. |
| |
| Requires: a recv_batch with final_state == GRPC_STREAM_CLOSED has been |
| received by the up-layer. Must not be called in the same call stack as |
| recv_frame. |
| |
| Arguments: |
| transport - the transport on which to create this stream |
| stream - the grpc_stream to destroy (memory is still owned by the |
| caller, but any child memory must be cleaned up) */ |
| void grpc_transport_destroy_stream(grpc_transport* transport, |
| grpc_stream* stream, |
| grpc_closure* then_schedule_closure); |
| |
| void grpc_transport_stream_op_batch_finish_with_failure( |
| grpc_transport_stream_op_batch* op, grpc_error* error, |
| grpc_call_combiner* call_combiner); |
| |
| char* grpc_transport_stream_op_batch_string(grpc_transport_stream_op_batch* op); |
| char* grpc_transport_op_string(grpc_transport_op* op); |
| |
| /* Send a batch of operations on a transport |
| |
| Takes ownership of any objects contained in ops. |
| |
| Arguments: |
| transport - the transport on which to initiate the stream |
| stream - the stream on which to send the operations. This must be |
| non-NULL and previously initialized by the same transport. |
| op - a grpc_transport_stream_op_batch specifying the op to perform |
| */ |
| void grpc_transport_perform_stream_op(grpc_transport* transport, |
| grpc_stream* stream, |
| grpc_transport_stream_op_batch* op); |
| |
| void grpc_transport_perform_op(grpc_transport* transport, |
| grpc_transport_op* op); |
| |
| /* Send a ping on a transport |
| |
| Calls cb with user data when a response is received. */ |
| void grpc_transport_ping(grpc_transport* transport, grpc_closure* cb); |
| |
| /* Advise peer of pending connection termination. */ |
| void grpc_transport_goaway(grpc_transport* transport, grpc_status_code status, |
| grpc_slice debug_data); |
| |
| /* Destroy the transport */ |
| void grpc_transport_destroy(grpc_transport* transport); |
| |
| /* Get the endpoint used by \a transport */ |
| grpc_endpoint* grpc_transport_get_endpoint(grpc_transport* transport); |
| |
| /* Allocate a grpc_transport_op, and preconfigure the on_consumed closure to |
| \a on_consumed and then delete the returned transport op */ |
| grpc_transport_op* grpc_make_transport_op(grpc_closure* on_consumed); |
| /* Allocate a grpc_transport_stream_op_batch, and preconfigure the on_consumed |
| closure |
| to \a on_consumed and then delete the returned transport op */ |
| grpc_transport_stream_op_batch* grpc_make_transport_stream_op( |
| grpc_closure* on_consumed); |
| |
| #endif /* GRPC_CORE_LIB_TRANSPORT_TRANSPORT_H */ |