int rd_kafka_sasl_io_event (rd_kafka_transport_t *rktrans, int events,
char *errstr, int errstr_size) {
if (events & POLLIN) {
rd_kafka_buf_t *rkbuf;
int r;
r = rd_kafka_transport_framed_recvmsg(rktrans, &rkbuf,
errstr, errstr_size);
if (r == -1)
return -1;
else if (r == 0)
return 0;
return rd_kafka_sasl_handle_recv(rktrans, rkbuf,
errstr, errstr_size);
}
return 0;
}
/**
* Length framed receive handling.
* Currently only supports a the following framing:
* [int32_t:big_endian_length_of_payload][payload]
*
* To be used on POLLIN event, will return:
* -1: on fatal error (errstr will be updated, *rkbufp remains unset)
* 0: still waiting for data (*rkbufp remains unset)
* 1: data complete, (buffer returned in *rkbufp)
*/
int rd_kafka_transport_framed_recvmsg (rd_kafka_transport_t *rktrans,
rd_kafka_buf_t **rkbufp,
char *errstr, size_t errstr_size) {
rd_kafka_buf_t *rkbuf = rktrans->rktrans_recv_buf;
ssize_t r;
const int log_decode_errors = 0;
/* States:
* !rktrans_recv_buf: initial state; set up buf to receive header.
* rkbuf_len == 0: awaiting header
* rkbuf_len > 0: awaiting payload
*/
if (!rkbuf) {
rkbuf = rd_kafka_buf_new(NULL, 1, 4);
/* Point read buffer to main buffer. */
rkbuf->rkbuf_rbuf = rkbuf->rkbuf_buf;
rd_kafka_buf_push(rkbuf, rkbuf->rkbuf_buf, 4);
rktrans->rktrans_recv_buf = rkbuf;
}
r = rd_kafka_transport_recvmsg(rktrans, &rkbuf->rkbuf_msg,
errstr, errstr_size);
if (r == 0)
return 0;
else if (r == -1)
return -1;
rkbuf->rkbuf_wof += r;
if (rkbuf->rkbuf_len == 0) {
/* Frame length not known yet. */
int32_t frame_len;
if (rkbuf->rkbuf_wof < sizeof(frame_len)) {
/* Wait for entire frame header. */
return 0;
}
/* Reader header: payload length */
rd_kafka_buf_read_i32(rkbuf, &frame_len);
if (frame_len < 0 ||
frame_len > rktrans->rktrans_rkb->
rkb_rk->rk_conf.recv_max_msg_size) {
rd_snprintf(errstr, errstr_size,
"Invalid frame size %"PRId32, frame_len);
return -1;
}
rkbuf->rkbuf_len = frame_len;
if (frame_len == 0) {
/* Payload is empty, we're done. */
rktrans->rktrans_recv_buf = NULL;
*rkbufp = rkbuf;
return 1;
}
/* Allocate memory to hold entire frame payload in contigious
* memory. */
rd_kafka_buf_alloc_recvbuf(rkbuf, frame_len);
/* Try reading directly, there is probably more data available*/
return rd_kafka_transport_framed_recvmsg(rktrans, rkbufp,
errstr, errstr_size);
}
if (rkbuf->rkbuf_wof == rkbuf->rkbuf_len) {
/* Payload is complete. */
rktrans->rktrans_recv_buf = NULL;
*rkbufp = rkbuf;
return 1;
}
/* Wait for more data */
return 0;
err:
if (rkbuf)
rd_kafka_buf_destroy(rkbuf);
rd_snprintf(errstr, errstr_size, "Frame header parsing failed");
return -1;
}
