static void send_response(int sock, int err_code, const json_t *ret)
{
char *buf = NULL;
size_t len;
json_t *res = NULL;
res = json_object();
if(res == NULL)
goto end;
json_object_set_new(res, "err_code", json_integer(err_code));
json_object_set(res, "ret", (json_t *)ret);
buf = json_dumps(res, JSON_COMPACT | JSON_ENSURE_ASCII);
if(buf == NULL)
goto end;
len = strlen(buf);
if(send_full(sock, &len, sizeof(len)) != sizeof(len)) {
log_error_errno();
goto end;
}
if(send_full(sock, buf, len) != len) {
log_error_errno();
goto end;
}
end:
if(buf)
free(buf);
if(res)
json_decref(res);
}
int main(int argc, char *argv[])
{
// get tcp socket file descriptor (fd) using server IP address
int sockfd;
if (argc != 2) {
printf("Using localhost. You can use: %s ipaddress\n", argv[0]);
sockfd = get_socket_tcp("127.0.0.1");
} else {
sockfd = get_socket_tcp(argv[1]);
}
fd_set read_fds; // set of fds used in function select()
uint8_t stdin_fd = STDIN_FILENO; // store fd for stdin
uint8_t nbytes;
uint8_t msg_len;
char ch;
char txtbuf[MSGSIZE];
printf("Start chatting\n");
while (1) {
// clear read_fds and add fds for stdin and tcp socket
FD_ZERO(&read_fds);
FD_SET(stdin_fd, &read_fds);
FD_SET(sockfd, &read_fds);
// monitor fds
if (select(sockfd + 1, &read_fds, NULL, NULL, NULL) < 0)
perror("select()");
// recv()'d something from the server
if (FD_ISSET(sockfd, &read_fds)) {
memset(txtbuf, '\0', MSGSIZE);
if ((nbytes = recv(sockfd, txtbuf, MSGSIZE - 1, 0)) < 0) {
perror("recv()");
return -1;
}
if (nbytes == 0) { // connection closed
printf("Server disconnected\n");
return 1;
}
printf("> '%s'\n", txtbuf);
}
// user is typing a message
if (FD_ISSET(stdin_fd, &read_fds)) {
memset(txtbuf, '\0', MSGSIZE);
if (fgets(txtbuf, MSGSIZE, stdin) == NULL)
perror("fgets()");
// get rid of unnecessary characters
txtbuf[strcspn(txtbuf, "\r\n")] = '\0';
msg_len = strlen(txtbuf);
// clear the stdin buffer
if (msg_len == MSGSIZE - 1)
while ((ch = getchar()) != '\n' && ch != EOF);
if (send_full(sockfd, txtbuf, msg_len, 0) < 0)
perror("send_full()");
}
}
close(sockfd);
return 0;
}
