/**
* Invoked when a client connection has data ready to be read.
* We need to take care to add the data to our buffers, and then
* invoke the connection handlers who have the business logic
* of what to do.
*/
static int read_client_data(conn_info *conn) {
/**
* Figure out how much space we have to write.
* If we have < 50% free, we resize the buffer using
* a multiplier.
*/
int avail_buf = circbuf_avail_buf(&conn->input);
if (avail_buf < conn->input.buf_size / 2) {
circbuf_grow_buf(&conn->input);
}
// Build the IO vectors to perform the read
struct iovec vectors[2];
int num_vectors;
circbuf_setup_readv_iovec(&conn->input, (struct iovec*)&vectors, &num_vectors);
// Issue the read
ssize_t read_bytes = readv(conn->client.fd, (struct iovec*)&vectors, num_vectors);
// Make sure we actually read something
if (read_bytes == 0) {
syslog(LOG_DEBUG, "Closed client connection. [%d]\n", conn->client.fd);
return 1;
} else if (read_bytes == -1) {
if (errno != EAGAIN && errno != EINTR) {
syslog(LOG_ERR, "Failed to read() from connection [%d]! %s.",
conn->client.fd, strerror(errno));
}
return 1;
}
// Update the write cursor
circbuf_advance_write(&conn->input, read_bytes);
return 0;
}
/**
* Invoked when a UDP connection has a message ready to be read.
* We need to take care to add the data to our buffers, and then
* invoke the connection handlers who have the business logic
* of what to do.
*/
static void handle_udp_message(ev_io *watch, int ready_events) {
while (1) {
// Get the associated connection struct
conn_info *conn = watch->data;
// Clear the input buffer
circbuf_clear(&conn->input);
// Build the IO vectors to perform the read
struct iovec vectors[2];
int num_vectors;
circbuf_setup_readv_iovec(&conn->input, (struct iovec*)&vectors, &num_vectors);
/*
* Issue the read, always use the first vector.
* since we just cleared the buffer, and it should
* be a contiguous buffer.
*/
assert(num_vectors == 1);
ssize_t read_bytes = recv(watch->fd, vectors[0].iov_base,
vectors[0].iov_len, 0);
// Make sure we actually read something
if (read_bytes == 0) {
syslog(LOG_DEBUG, "Got empty UDP packet. [%d]\n", watch->fd);
return;
} else if (read_bytes == -1) {
if (errno != EAGAIN && errno != EINTR) {
syslog(LOG_ERR, "Failed to recv() from connection [%d]! %s.",
watch->fd, strerror(errno));
}
return;
}
// Update the write cursor
circbuf_advance_write(&conn->input, read_bytes);
// UDP clients don't need to append newlines to the messages like
// TCP clients do, but our parser requires them. Append one if
// it's not present.
if (conn->input.buffer[conn->input.write_cursor - 1] != '\n')
circbuf_write(&conn->input, "\n", 1);
// Get the user data
worker_ev_userdata *data = ev_userdata();
// Invoke the connection handler
statsite_conn_handler handle = {data->netconf->config, watch->data};
handle_client_connect(&handle);
}
}