vtls: change send/recv signatures of tls backends

[icing]

Similar to connection filter changes, return a CURLcode and the read/written amount as size_t *.

[testclutch]

Analysis of PR #17593 at 65b84e77:

Test 410 failed, which has NOT been flaky recently, so there could be a real issue in this PR. Note that this test has failed in 6 different CI jobs (the link just goes to one of them).

Generated by Testclutch

[jay]

please check if the valgrind ci failure is related. the ancestor you branched from does not have this failure.

=== Start of file valgrind410
 ==119773== Conditional jump or move depends on uninitialised value(s)
 ==119773==    at 0x48E9234: out_number (mprintf.c:793)
 ==119773==    by 0x48E9CAE: formatf (mprintf.c:1041)
 ==119773==    by 0x48E9F96: curl_mvsnprintf (mprintf.c:1113)
 ==119773==    by 0x489EFB9: trc_infof (curl_trc.c:230)
 ==119773==    by 0x489F32B: Curl_trc_cf_infof (curl_trc.c:253)
 ==119773==    by 0x493F03F: mbed_send (mbedtls.c:1249)
 ==119773==    by 0x4944068: ssl_cf_send (vtls.c:1489)
 ==119773==    by 0x4889B10: Curl_cf_def_send (cfilters.c:105)
 ==119773==    by 0x4889B10: Curl_cf_def_send (cfilters.c:105)
 ==119773==    by 0x488A45C: Curl_cf_send (cfilters.c:269)
 ==119773==    by 0x488C5B9: Curl_conn_send (cfilters.c:941)
 ==119773==    by 0x4923116: Curl_xfer_send (transfer.c:941)
 ==119773==    by 0x4902580: xfer_send (request.c:215)
 ==119773==    by 0x49026F2: req_send_buffer_flush (request.c:242)
 ==119773==    by 0x4902B11: req_flush (request.c:296)
 ==119773==    by 0x490327A: Curl_req_send_more (request.c:446)

[icing]

please check if the valgrind ci failure is related. the ancestor you branched from does not have this failure.

Thanks, fixed via cfa807a

[jay]

lgtm but I'll leave it to @bagder whether to land it for rc-8_15_0-1 for today

[bagder]

👍