/*
 *
 * 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_IOMGR_SOCKET_MUTATOR_H
#define GRPC_CORE_LIB_IOMGR_SOCKET_MUTATOR_H

#include <grpc/impl/codegen/grpc_types.h>
#include <grpc/support/sync.h>

#include <stdbool.h>

#ifdef __cplusplus
extern "C" {
#endif

/** The virtual table of grpc_socket_mutator */
typedef struct {
  /** Mutates the socket opitons of \a fd */
  bool (*mutate_fd)(int fd, grpc_socket_mutator *mutator);
  /** Compare socket mutator \a a and \a b */
  int (*compare)(grpc_socket_mutator *a, grpc_socket_mutator *b);
  /** Destroys the socket mutator instance */
  void (*destory)(grpc_socket_mutator *mutator);
} grpc_socket_mutator_vtable;

/** The Socket Mutator interface allows changes on socket options */
struct grpc_socket_mutator {
  const grpc_socket_mutator_vtable *vtable;
  gpr_refcount refcount;
};

/** called by concrete implementations to initialize the base struct */
void grpc_socket_mutator_init(grpc_socket_mutator *mutator,
                              const grpc_socket_mutator_vtable *vtable);

/** Wrap \a mutator as a grpc_arg */
grpc_arg grpc_socket_mutator_to_arg(grpc_socket_mutator *mutator);

/** Perform the file descriptor mutation operation of \a mutator on \a fd */
bool grpc_socket_mutator_mutate_fd(grpc_socket_mutator *mutator, int fd);

/** Compare if \a a and \a b are the same mutator or have same settings */
int grpc_socket_mutator_compare(grpc_socket_mutator *a, grpc_socket_mutator *b);

grpc_socket_mutator *grpc_socket_mutator_ref(grpc_socket_mutator *mutator);
void grpc_socket_mutator_unref(grpc_socket_mutator *mutator);

#ifdef __cplusplus
}
#endif

#endif /* GRPC_CORE_LIB_IOMGR_SOCKET_MUTATOR_H */
