static void
ui_handler(evutil_socket_t fd, short what, void *arg)
{
struct uiclient *client = arg;
if (evbuffer_read(client->inbuf, fd, -1) <= 0) {
ui_dead(client);
return;
}
for (;;) {
size_t eol_len;
struct evbuffer_ptr line = evbuffer_search_eol(client->inbuf, NULL, &eol_len, EVBUFFER_EOL_LF);
if (line.pos == -1)
break;
char *p = (char *)malloc(line.pos + 1);
if (p != NULL) {
evbuffer_remove(client->inbuf, (void *)p, line.pos);
p[line.pos] = '\0'; /* ensure termination */
evbuffer_drain(client->inbuf, eol_len);
ui_handle_command(client->outbuf, p);
free(p);
}
}
ui_write_prompt(client);
event_add(client->ev_read, NULL);
}
static void echo_read_cb(struct bufferevent *bev, void *ctx)
{
/* This callback is invoked when there is data to read on bev. */
struct evbuffer *input = bufferevent_get_input(bev);
struct evbuffer *output = bufferevent_get_output(bev);
while (1) {
size_t eol_len = 0;
struct evbuffer_ptr eol = evbuffer_search_eol(input, NULL, &eol_len, EVBUFFER_EOL_LF);
if (eol.pos < 0) {
// not found '\n'
size_t readable = evbuffer_get_length(input);
if (readable > MAX_LINE_LENGTH) {
printf("input is too long %zd\n", readable);
bufferevent_free(bev);
}
break;
}
else if (eol.pos > MAX_LINE_LENGTH) {
printf("line is too long %zd\n", eol.pos);
bufferevent_free(bev);
break;
}
else {
assert(eol_len == 1);
// int nr = evbuffer_remove_buffer(input, output, eol.pos+1);
// copy input buffer to request
char request[MAX_LINE_LENGTH+1];
assert(eol.pos+1 <= sizeof(request));
int req_len = evbuffer_remove(input, request, eol.pos+1);
assert(req_len == eol.pos+1);
// business logic
char response[MAX_LINE_LENGTH+1];
int resp_len = req_len;
memcpy(response, request, req_len);
// copy response to output buffer
int succeed = evbuffer_add(output, response, resp_len);
assert(succeed == 0);
// high water mark check
if (evbuffer_get_length(output) > MAX_OUTPUT_BUFFER) {
// or, stop reading
bufferevent_free(bev);
break;
}
}
}
}