src/core/client_config/subchannel.h

/*
 *
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#ifndef GRPC_INTERNAL_CORE_CLIENT_CONFIG_SUBCHANNEL_H
#define GRPC_INTERNAL_CORE_CLIENT_CONFIG_SUBCHANNEL_H

#include "src/core/channel/channel_stack.h"
#include "src/core/iomgr/iomgr.h"
#include "src/core/iomgr/sockaddr.h"
#include "src/core/transport/transport.h"

/** A (sub-)channel that knows how to connect to exactly one target
    address. Provides a target for load balancing. */
typedef struct grpc_subchannel grpc_subchannel;
typedef struct grpc_subchannel_call grpc_subchannel_call;

void grpc_subchannel_ref(grpc_subchannel *channel);
void grpc_subchannel_unref(grpc_subchannel *channel);

void grpc_subchannel_call_ref(grpc_subchannel_call *call);
void grpc_subchannel_call_unref(grpc_subchannel_call *call);

/** poll the current connectivity state of a channel */
grpc_connectivity_state grpc_subchannel_check_connectivity(
    grpc_subchannel *channel);

/** call notify when the connectivity state of a channel changes from *state.
    Updates *state with the new state of the channel */
void grpc_subchannel_notify_on_state_change(grpc_subchannel *channel,
                                            grpc_connectivity_state *state,
                                            grpc_iomgr_closure *notify);

/** construct a call */
grpc_subchannel_call *grpc_subchannel_create_call(
    grpc_subchannel *subchannel, grpc_call_element *parent,
    grpc_transport_stream_op *initial_op);

/** continue processing a transport op */
void grpc_subchannel_call_process_op(grpc_subchannel_call *subchannel_call,
                                     grpc_transport_stream_op *op);

#endif /* GRPC_INTERNAL_CORE_CLIENT_CONFIG_SUBCHANNEL_H */