libsocket.h

// Copyright 2019 Google LLC
//
// 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
//
// https://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 LIBSOCKET_H
#define LIBSOCKET_H

#include <stdint.h>
#include <sys/types.h>
#if defined(_WIN32)
#include <WinSock2.h>
#endif

#if defined(_WIN32)
typedef SOCKET socket_t;

// We need C11 or newer due to the use of `_Generic`.  Windows does not have a
// signed size type, so we construct the equivalent type by inspecting the type
// of `size_t` and mapping from the signed to the unsigned version.
#if __STDC_VERSION__-0 >= 201112l
typedef __typeof__(_Generic((size_t)0,                                  \
                            unsigned long long int : (long long int)0,  \
                            unsigned long int : (long int)0,            \
                            unsigned int : (int)0,                      \
                            unsigned short : (short)0,                  \
                            unsigned char : (char)0)) ssize_t;
#endif
#else
typedef int libsocket_t;
#define INVALID_SOCKET (-1)
#endif

libsocket_t socket_listen(const char* address, uint16_t port);
libsocket_t socket_accept(libsocket_t socket);
libsocket_t socket_connect(const char* address, uint16_t port);

ssize_t socket_send(libsocket_t socket, const uint8_t* data, size_t length);
ssize_t socket_recv(libsocket_t socket, uint8_t* buffer, size_t length);

int socket_shutdown(libsocket_t socket);
int socket_close(libsocket_t socket);

#endif