I've now made TFTP "connections" not being kept for re-use within libcurl.
TFTP is UDP-based so the benefit was really low (if even existing) to begin
with so instead of tracking down to fix this problem we instead removed the
re-use. I also enabled test case 1099 that I wrote a few days ago to verify
that this change fixes the reported problem.
Chen pointed out how curl couldn't upload with resume when reading from a
pipe.
This ended up with the introduction of a new return code for the
CURLOPT_SEEKFUNCTION callback that basically says that the seek failed but
that libcurl may try to resolve the situation anyway. In our case this means
libcurl will attempt to instead read that much data from the stream instead
of seeking and that way curl can now upload with resume when data is read
from a stream!
Previous workaround proved useful, but triggered the following warning:
warning #556: a value of type "volatile Curl_addrinfo *" cannot be assigned to an entity of type "Curl_addrinfo *"
Previous 'volatile' variables workaround proved useful, but it triggered the following warning:
warning #167: argument of type "volatile Curl_addrinfo *" is incompatible with parameter of type "void *"
how it occurs (http://curl.haxx.se/mail/lib-2009-04/0289.html). The
conclusion was that if an error is detected and Curl_done() is called for
the connection, ftp_done() could at times return another error code that
then would take precedence and that new code confused existing logic that
works for the first error code (CURLE_SEND_ERROR) only.
proxy. libcurl would then wrongly close the connection after each
request. In his case it had the weird side-effect that it killed NTLM auth
for the proxy causing an inifinite loop!
I added test case 1098 to verify this fix. The test case does however not
properly verify that the transfers are done persistently - as I couldn't
think of a clever way to achieve it right now - but you need to read the
stderr output after a test run to see that it truly did the right thing.
Storsjo pointed out how setting CURLOPT_NOBODY to 0 could be downright
confusing as it set the method to either GET or HEAD. The example he showed
looked like:
curl_easy_setopt(curl, CURLOPT_PUT, 1);
curl_easy_setopt(curl, CURLOPT_NOBODY, 0);
The new way doesn't alter the method until the request is about to start. If
CURLOPT_NOBODY is then 1 the HTTP request will be HEAD. If CURLOPT_NOBODY is
0 and the request happens to have been set to HEAD, it will then instead be
set to GET. I believe this will be less surprising to users, and hopefully
not hit any existing users badly.
out to be leaking cacerts. Kamil Dudka helped me complete the fix. The issue
is found in Redhat's bug tracker:
https://bugzilla.redhat.com/show_bug.cgi?id=453612
There are still memory leaks present, but they seem to have other reasons.