The IP version choice was previously only in the UserDefined struct
within the SessionHandle, but since we sometimes alter that option
during a request we need to have it on a per-connection basis.

I also moved more "init conn" code into the allocate_conn() function
which is designed for that purpose more or less.

I found a bug in tftp_tx() in tftp.c. If a data resend is done after
reception of an ACK/OACK, the call to sendto is wrong.

Bug: https://bugzilla.redhat.com/650255
Reported by: Simon H.

... and do not send ABOR unless really necessary.

Bug: https://bugzilla.redhat.com/649347
Reported by: Simon H.

CURLOPT_RESOLVE is a new option that sends along a curl_slist with
name:port:address sets that will populate the DNS cache with entries so
that request can be "fooled" to use another host than what otherwise
would've been used. Previously we've encouraged the use of Host: for
that when dealing with HTTP, but this new feature has the added bonus
that it allows the name from the URL to be used for TLS SNI and server
certificate name checks as well.

This is a first change. Surely more will follow to make it decent.

If the query result has a binary attribute, the binary attribute is
base64 encoded. But all following non binary attributes are also base64
encoded which is wrong.

This is a test (LDAP server is public).

curl
ldap://x500.bund.de:389/o=Bund,c=DE?userCertificate,certificateSerialNumber?sub
?cn=*Woehleke*

This reverts commit b0fd03f5,
4b2fbe1e, afecd1aa, 68cde058

If you use a custom Host: name in a request to a SSL server, libcurl
will now use that given name when it verifies the server certificate to
be correct rather than using the host name used in the actual URL.

The redirect check is already done at the position where the customhost
field is assigned so there's no point in doing that a second time.

When given a custom host name in a Host: header, we can use it for
several different purposes other than just cookies, so we rename it and
use it for SSL SNI etc.

OpenSSL SNI host name should be set to the custom Host header, if the
user provided one.

Some FTP servers (e.g. Pure-ftpd) end up hanging if we close the data
connection before transferring all the requested data.  If we send ABOR
in that case, it prevents the server from hanging.

Bug: https://bugzilla.redhat.com/643656
Reported by: Pasi Karkkainen, Patrick Monnerat

These haven't worked in at least 8 years due to missing source
files, and most active RiscOS developers these days apparently
cross-compile anyway.

Signed-off-by: James Bursa <james@zamez.org>

Also, added a few hints to help compilers to perform tail call
recursion optimization.

In libssh2 1.2.8, libssh2_session_handshake() replaces
libssh2_session_startup() to fix the previous portability problem with
the socket type that was too small for win64 and thus easily could cause
crashes and more.

It is a bad idea to use the public prefix used by another library and
now we realize that libssh2 introduces a symbol in the upcoming version
1.2.8 that conflicts with our static function named libssh2_free.

When failing to build form post due to an error, the code now does a
proper failf(). Previously libcurl would report an error like "failed
creating formpost data" when a file wasn't possible to open which was
not easy for users to figure out.

I also lower cased a function name to be named more curl-style and
removed some unnecessary code.

The URL parser got a little stricter as it now considers a ? to be a
host name divider so that the slightly sloppier URLs work too. The
problem that made me do this change was the reported problem with an URL
like: www.example.com?email=name@example.com This form of URL is not
really a legal URL (due to the missing slash after the host name) but is
widely accepted by all major browsers and libcurl also already accepted
it, it was just the '@' letter that triggered the problem now.

The side-effect of this change is that now libcurl no longer accepts the
?  letter as part of user-name or password when given in the URL, which
it used to accept (and is tested in test 191). That letter is however
mentioned in RFC3986 to be required to be percent encoded since it is
used as a divider.

Bug: http://curl.haxx.se/bug/view.cgi?id=3090268

Accidentally left in there during my previous debugging of this

In order to avoid for example the pingpong protocols to issue STARTTLS
(or equivalent) even though there's no SSL support built-in.

Reported by: Sune Ahlgren
Bug: http://curl.haxx.se/mail/archive-2010-10/0045.html

As the change in 5f0ae7a0 added a precaution against negative
file sizes that for some reason managed to get returned, this change now
introduces the same check at the second place in the code where the file
size from the libssh2 stat call is used.

This check might not be suitable for a 32 bit curl_off_t, but libssh2.h
assumes long long to work and to be 64 bit so I believe such a small
curl_off_t will be very unlikely to occur in the wild.

... and some minor source code whitespace edits

Renamed SDK_* to NDK_*; made NDK_* defines overwriteable from
environment; removed now obsolete YACC macro;
moved some curl_config.h defines to IPv6 section since they
are only needed when IPv6 is enabled - this makes libcurl compile
with older NDKs too which were not IPv6-aware.

We forgot to release the buffer passed to gss_init_sec_context.

The previous logic was difficult to read as we were reusing the same
variable (gssbuf) for both input buffer and output buffer. Splitted the
logic in 2 variables to better underline who needs to be released.
Also made the code break at 80 lines.

kr5_auth missed a final 'return' statement. This is not an error in
gcc but can lead to potential bugs.

This fixes a memory leak related to the GSS-API code.

Added a krb5_init and krb5_end functions. Also removed a work-around
the lack of proper initialization of the GSS-API context.

It was pointed out that the special case libcurl did for 416 was
incorrect and wrong. 416 is not really different to other errors so the
response body must be handled like for other errors/http responses.

Reported by: Chris Smowton
Bug: http://curl.haxx.se/bug/view.cgi?id=3076808

It is still not clarified exactly why this happens, but libssh2
sometimes report a negative file size for the remote SFTP file and that
deeply confuses libcurl (or crashes it) so this precaution is added to
avoid badness.

Reported by: Ernest Beinrohr
Bug: http://curl.haxx.se/bug/view.cgi?id=3076430