Receive file from server using send and fwrite - c

Question

Hello I am working on a school lab in which I have to ask a server to send me a file. Here is my code so far. for some reason, when I run this code, in which I have fixed the arguments for debug purposes, it is as if I get in an infinite loop and get nothing. The problem is surely in gettftp function in the "send" function i think.
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <arpa/tftp.h>
#include <sys/socket.h>
#include <netinet/in.h>
int gettftp(const char *fileName, const char *serverIp)
{
int sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
struct sockaddr_in server_address;
server_address.sin_family = AF_INET;
server_address.sin_port = htons(69);
server_address.sin_addr.s_addr = inet_addr(serverIp);
//sending read request
struct tftphdr *read_request = (struct tftphdr *) malloc(sizeof(struct tftphdr) + strlen(fileName) + 1);
read_request->th_opcode = htons(RRQ);
strcpy(read_request->th_stuff, fileName);
send(sock, read_request, sizeof(struct tftphdr) + strlen(fileName) + 1, 0);
// Receive and save the file
FILE *fp = fopen(fileName, "wb");
while (1) {
char buffer[512];
int bytes_received = recv(sock, buffer, sizeof(buffer), 0);
if (bytes_received < 0) {
break;
}
fwrite(buffer, 1, bytes_received, fp);
}
fclose(fp);
close(sock);
return 0;
}
/**
* Send back the ip address of the requested server
* #param server name inputed right after file to be executed.
* #output none
*/
int main(int argc, char* argv[])
{
char* server, file;
char buffile[100],bufsN[100];
unsigned char ip[50] ="";
struct addrinfo hints, *results, *rp;
int sfd;
argv[1] = "10.10.32.11";
argv[2] = "alt256";
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC; /* Allow IPv4 or IPv6 */
hints.ai_socktype = SOCK_DGRAM; /* Datagram socket */
hints.ai_flags = 0;
hints.ai_protocol = 0; /* Any protocol */
if(argc<3)
{
printf("You have requested file :\033[0;31m%s\033[0m", argv[2]); //print file name. the part that has 31 changes color to red
printf(" from server : \033[0;31m%s\033[0m \n", argv[1]); //print server name
}
int status = getaddrinfo(argv[1], "69", &hints, &results);
if (status != 0) {
printf("Error: getaddrinfo: %s\n", gai_strerror(status)); //describes what the error does
return 1;
}
else
{
inet_ntop(AF_INET, &results->ai_addr->sa_data[2], ip, sizeof(ip)); //convert ip adress which is part of a struct to string
printf("L'adresse du serveur est: \033[0;31m%s\033[0m \n", ip); //print server ip address
}
for (rp = results; rp != NULL; rp = rp->ai_next) { //socket creation using address family (rp->ai_family), the socket type (ai_socktype)
sfd = socket(rp->ai_family, rp->ai_socktype, //and protocol(ai_protocol)
rp->ai_protocol);
if (sfd == -1) //in case sfd = -1 move on to the next iteration because there is some error somewhere
continue;
if (connect(sfd, rp->ai_addr, rp->ai_addrlen) != -1){ //if connection is successful print message and break out of the oop
printf("Connected to server: \033[0;31m%s\033[0m \n", argv[1] );
break; /* Success */
}
close(sfd);
}
if (rp == NULL) { /* No address succeeded */
fprintf(stderr, "Could not connect\n");
exit(EXIT_FAILURE);
}
//const char* filen = "alt256";
const char* filen = argv[2];
//const char* serverName = "srvtpinfo1.ensea.fr";
strcpy(buffile, filen);
strcpy(bufsN, ip);
gettftp(buffile, bufsN);
//gettftp("alt256", "10.10.32.11");
return 0;
}
}
I have tries debugging to see if the parameters are right when they get in the function and that was the case