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helper.c
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helper.c
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#include "helper.h"
#include "defs.h"
#include <arpa/inet.h>
int initserver(char *addr, char *port) {
int status, sockfd;
struct addrinfo hints;
struct addrinfo *result, *p;
memset(&hints, 0, sizeof hints); // empty struct
hints.ai_family = AF_UNSPEC; // ipv4/6
hints.ai_socktype = SOCK_STREAM; // tcp
hints.ai_flags = AI_PASSIVE; // assigns the address of local host
// to the socket
if ((status = getaddrinfo(addr, port, &hints, &result)) != 0) {
fprintf(stderr, "Error with getting address: %s\n",
gai_strerror(status));
return -1;
}
// result -> linked list of addrinfos for localhost:PORT
// loop through the entire linked list
for (p = result; p != NULL; p = p->ai_next) {
if ((sockfd = socket(result->ai_family, result->ai_socktype,
result->ai_protocol)) == -1) {
continue;
}
if (bind(sockfd, result->ai_addr, result->ai_addrlen) == -1) {
close(sockfd);
continue;
}
break;
}
if (p == NULL) {
fprintf(stderr, "Failed to bind: %s:%s\n", addr, port);
exit(1);
}
// listen for incoming connectionss
if (listen(sockfd, BACKLOG) == -1) {
fprintf(stderr, "Error listening: %d\n", errno);
return -1;
}
printf("Listening on port %s\n", port);
return sockfd;
}
// initialises connection with server
// {address, port} -> socket fd
int initconn(char *addr, char *port) {
int status;
struct addrinfo hints;
struct addrinfo *result, *p;
memset(&hints, 0, sizeof hints); // empty struct
hints.ai_family = AF_UNSPEC; // ipv4/6
hints.ai_socktype = SOCK_STREAM; // tcp
hints.ai_flags = AI_PASSIVE; // assigns the address of local host
// to the socket
if ((status = getaddrinfo(addr, port, &hints, &result)) != 0) {
fprintf(stderr, "Error with getting address: %s\n",
gai_strerror(status));
return -1;
}
int sockfd; // socket descriptor
// loop through the entire linked list
for (p = result; p != NULL; p = p->ai_next) {
if ((sockfd = socket(result->ai_family, result->ai_socktype,
result->ai_protocol)) == -1) {
continue;
}
break;
}
if (p == NULL) {
fprintf(stderr, "Failed to bind\n");
return -1;
}
if (connect(sockfd, result->ai_addr, result->ai_addrlen) == -1) {
fprintf(stderr, "Error connecting to the server.\nAre you sure the "
"server is up?\n");
return -1;
} else {
printf("Connection established with %s!\n", port);
}
return sockfd;
}
// recv with errors
int recver(int sockfd, char *buf, int len, int flags) {
int r;
if ((r = recv(sockfd, buf, len, flags)) == -1) {
fprintf(stderr, "Issues recv reqs: %d\n", errno);
return -1;
};
return r;
}
// Function to get IP address from socket
char *getip(int sockfd) {
struct sockaddr_storage addr;
socklen_t addr_len = sizeof(addr);
if (getpeername(sockfd, (struct sockaddr *)&addr, &addr_len) == 0) {
// The socket is connected, and addr now contains the peer's address
char *ipstr = (char *)malloc(sizeof(char) * INET6_ADDRSTRLEN);
int port;
if (addr.ss_family == AF_INET) {
struct sockaddr_in *s = (struct sockaddr_in *)&addr;
port = ntohs(s->sin_port);
inet_ntop(AF_INET, &s->sin_addr, ipstr, sizeof ipstr);
} else { // AF_INET6
struct sockaddr_in6 *s = (struct sockaddr_in6 *)&addr;
port = ntohs(s->sin6_port);
inet_ntop(AF_INET6, &s->sin6_addr, ipstr, sizeof ipstr);
}
// printf("Peer IP address: %s\n", ipstr);
return ipstr;
} else {
perror("Could not get IP address...\n");
}
}
void sender(int sockfd, char *buf, int len) {
if ((send(sockfd, buf, len, 0)) == -1) {
fprintf(stderr, "Issues sending req: %d\n", errno);
exit(0);
};
}