/*
* Read client response from an HTTP request into a buffer. Return the number of
* characters written to buf (EXCLUDING null character);
*/
void
extract_client_response(struct HTTPObject *h, EthernetClient client){
extract_status_code(h, client);
skip_http_headers(client);
extract_body(h, client);
// Clean up the connection
client.flush();
client.stop();
}
int retrieve_chatserver_info(char *chatserver_name, u_int16_t *tcp_port, u_int16_t *udp_port)
{
int locn_socket_fd;
char *buf;
int buflen;
int code;
int n;
/* Initialize locnserver_addr.
* We use a text file at a web server for location info
* so this is just contacting the CDF web server
*/
/*
* 1. Set up TCP connection to web server "www.cdf.toronto.edu",
* port 80
*/
/* The code you write should initialize locn_socket_fd so that
* it is valid for the write() in the next step.
*/
int status;
struct addrinfo hints;
struct addrinfo *res; // pointer for the results
memset(&hints, 0, sizeof(hints)); // make sure the struct is empty
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
status = getaddrinfo("www.cdf.toronto.edu", "http", &hints, &res);
if (status != 0) {
return -1;
}
// make a tcp socket
locn_socket_fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (locn_socket_fd < 0) {
freeaddrinfo(res);
return -1;
}
// connect to the server
status = connect(locn_socket_fd, res->ai_addr, res->ai_addrlen);
if (status != 0) {
freeaddrinfo(res);
close(locn_socket_fd);
return -1;
}
/* 2. write HTTP GET request to socket */
buf = (char *)malloc(MAX_MSG_LEN);
bzero(buf, MAX_MSG_LEN);
build_req(buf);
buflen = strlen(buf);
write(locn_socket_fd, buf, buflen);
/* 3. Read reply from web server */
read(locn_socket_fd, buf, MAX_MSG_LEN);
/*
* 4. Check if request succeeded. If so, skip headers and initialize
* server parameters with body of message. If not, print the
* STATUS-CODE and STATUS-TEXT and return -1.
*/
/* Ignore version, read STATUS-CODE into variable 'code' , and record
* the number of characters scanned from buf into variable 'n'
*/
sscanf(buf, "%*s %d%n", &code, &n);
if (code >= 200 && code < 300) { // success!
int eol = find_nn(buf, MAX_MSG_LEN);
assert(eol >= 0);
//printf("HTTP %d", code); // for debugging
int i;
for (i = n; i < eol; ++i) {
putchar(buf[i]);
}
printf("\n");
// get the server info
char *body = skip_http_headers(buf);
sscanf(body, "%s %hu %hu", chatserver_name, tcp_port, udp_port);
} else {
// not success, so print out status and message
int eol = find_nn(buf, MAX_MSG_LEN);
assert(eol >= 0);
printf("HTTP error %d", code);
int i;
for (i = n; i < eol; ++i) {
putchar(buf[i]);
}
printf("\n");
free(buf);
freeaddrinfo(res);
close(locn_socket_fd);
return -1;
}
/* 5. Clean up after ourselves and return. */
free(buf);
freeaddrinfo(res);
close(locn_socket_fd);
return 0;
}