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#include "network.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
/*
* Create a file descriptor connected to a socket peer.
* Client sockets will be connected, listening sockets will be bound.
* Returns -1 in case of failure, a valid fd otherwise.
*/
int network_socket(char* host, char* port, int socktype, int listener){
int fd = -1, status, yes = 1, flags;
struct addrinfo hints = {
.ai_family = AF_UNSPEC,
.ai_socktype = socktype,
.ai_flags = (listener ? AI_PASSIVE : 0)
};
struct addrinfo *info, *addr_it;
status = getaddrinfo(host, port, &hints, &info);
if(status){
fprintf(stderr, "Failed to parse address %s port %s: %s\n", host, port, gai_strerror(status));
return -1;
}
//traverse the result list
for(addr_it = info; addr_it; addr_it = addr_it->ai_next){
fd = socket(addr_it->ai_family, addr_it->ai_socktype, addr_it->ai_protocol);
if(fd < 0){
continue;
}
//set required socket options
yes = 1;
if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void*)&yes, sizeof(yes)) < 0){
fprintf(stderr, "Failed to enable SO_REUSEADDR on socket: %s\n", strerror(errno));
}
yes = 0;
if(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&yes, sizeof(yes)) < 0){
fprintf(stderr, "Failed to unset IPV6_V6ONLY on socket: %s\n", strerror(errno));
}
//TODO loop, bcast for udp
if(listener){
status = bind(fd, addr_it->ai_addr, addr_it->ai_addrlen);
if(status < 0){
close(fd);
continue;
}
}
else{
status = connect(fd, addr_it->ai_addr, addr_it->ai_addrlen);
if(status < 0){
close(fd);
continue;
}
}
break;
}
freeaddrinfo(info);
if(!addr_it){
fprintf(stderr, "Failed to create socket for %s port %s\n", host, port);
return -1;
}
//set nonblocking
flags = fcntl(fd, F_GETFL, 0);
if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) < 0){
fprintf(stderr, "Failed to set socket nonblocking: %s\n", strerror(errno));
close(fd);
return -1;
}
if(!listener){
return fd;
}
if(socktype == SOCK_STREAM){
status = listen(fd, SOMAXCONN);
if(status < 0){
fprintf(stderr, "Failed to listen on socket: %s\n", strerror(errno));
close(fd);
return -1;
}
}
return fd;
}
/*
* Send arbitrary data over multiple writes if necessary.
* Returns 0 on success
*/
int network_send(int fd, uint8_t* data, size_t length){
//TODO probably should introduce send buffering at some point
ssize_t total = 0, sent;
while(total < length){
sent = send(fd, data + total, length - total, 0);
if(sent < 0){
fprintf(stderr, "Failed to send: %s\n", strerror(errno));
return 1;
}
total += sent;
}
return 0;
}
/*
* Send string data over multiple writes if necessary.
* Returns 0 on success
*/
int network_send_str(int fd, char* data){
return network_send(fd, (uint8_t*) data, strlen(data));
}
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