kws_read_frame when receive a short ping frame

[shanghaimoon888]

Where the function kws_read_frame() read a ping frame which the frame length is 6(2 header and 4 payload) and followed with a text frame. Then the code below will make the kws->datalen to be 9:
if ((kws->datalen = kws_string_read(kws, kws->buffer, 9 + 1, kws->block)) < 0)
This will trigger the error in below code because the need will be -3:
need = (kws->plen - (kws->datalen - need));
if (need < 0) {
/* invalid read - protocol err .. */
ks_log(KS_LOG_ERROR, "Read frame error because need = %ld\n", need);
*oc = WSOC_CLOSE;
return kws_close(kws, WS_NONE);
}
I have modify the code to:
if ((kws->datalen = kws_string_read(kws, kws->buffer, 6 + 1, kws->block)) < 0)
and it seems worked. But if the ping frame length is less than 6, the error is still exist. What about a perfect solution?

[chucongqing]

#181