src/core/lib/client_config/lb_policy_factory.h

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#ifndef GRPC_CORE_LIB_CLIENT_CONFIG_LB_POLICY_FACTORY_H
#define GRPC_CORE_LIB_CLIENT_CONFIG_LB_POLICY_FACTORY_H

#include "src/core/client_config/lb_policy.h"
#include "src/core/client_config/subchannel.h"

typedef struct grpc_lb_policy_factory grpc_lb_policy_factory;
typedef struct grpc_lb_policy_factory_vtable grpc_lb_policy_factory_vtable;

/** grpc_lb_policy provides grpc_client_config objects to grpc_channel
    objects */
struct grpc_lb_policy_factory {
  const grpc_lb_policy_factory_vtable *vtable;
};

typedef struct grpc_lb_policy_args {
  grpc_subchannel **subchannels;
  size_t num_subchannels;
} grpc_lb_policy_args;

struct grpc_lb_policy_factory_vtable {
  void (*ref)(grpc_lb_policy_factory *factory);
  void (*unref)(grpc_lb_policy_factory *factory);

  /** Implementation of grpc_lb_policy_factory_create_lb_policy */
  grpc_lb_policy *(*create_lb_policy)(grpc_lb_policy_factory *factory,
                                      grpc_lb_policy_args *args);

  /** Name for the LB policy this factory implements */
  const char *name;
};

void grpc_lb_policy_factory_ref(grpc_lb_policy_factory *factory);
void grpc_lb_policy_factory_unref(grpc_lb_policy_factory *factory);

/** Create a lb_policy instance. */
grpc_lb_policy *grpc_lb_policy_factory_create_lb_policy(
    grpc_lb_policy_factory *factory, grpc_lb_policy_args *args);

#endif /* GRPC_CORE_LIB_CLIENT_CONFIG_LB_POLICY_FACTORY_H */