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.

I've made the code intended using curl-style now to look more like other
examples.

My previous "fix" was a bit too invasive but is now fixed again.

An example application source code sending SMTP mail with the multi
interface. It is based on the code Alona Rossen provided, which in turn
is based on existing example/test code, and I converted it even more
into a decent example with a fair multi API use, put the info required
to edit at the top and I added some comments.

If a command is set type="perl", it can now specify a perl program that will
be run instead of an ordinary curl or built tool.

A perl test automatically disables memory and valgrind debugging.

This new script scans for all enums and #defines used by the curl/curl.h
and curl/multi.h headers. Then it reads all symbols mentioned in
symbols-in-vesions and make sure that there's no entries missing in
there. It then proceeds to verify that the entries that
symbols-in-vesions mentions but aren't found in the sources are truly
documented as removed.

This script is used in the new test case 1119

I've developed a script I call symbol-scan.pl that scans the curl.h and
multi.h header files and compare the symbols it finds in there with the
symbols symbols-in-versions documents and outputs a report on the
differences.  Using this I've dug through the history to fill up
symbols-in-versions with all the symbols my script found mismatches for.

I will commit symbol-scan.pl separatly and think of a way to put it to
use in the build/tests so that we from now on will get this in-sync
check automatically.

The new perl script mk580.pl generates a C table in a fresh source file
named lib580.c and if that compiles fine we know that the file
docs/libcurl/symbols-in-versions at least doesn't include any symbols
that are misspelled.

An additional feature would be to somehow scan curl/curl.h and compare
with symbols-in-versions to see if there are symbols missing.

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

It is for FTP, SMTP, POP3, IMAP at least.

"SFTP resume with 4GB file does not work" is now removed as I'm sure
this is really a libssh2 bug and not a libcurl bug.

7.21.2 is released already

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

Some options, such as the automatic decompression and some SSL related
ones now will bail out if the underlying libcurl doesn't have support
for the particular feature needed.

Reported by: Christian Weisgerber
Bug: http://curl.haxx.se/bug/view.cgi?id=3087479

The option takes a parameter that should be 1 or 0 to enable or disable
the feature.

URL: http://curl.haxx.se/bug/view.cgi?id=3086428

Modified Watcom targets to avoid backslashs so that they can
work on Linux too.