Fixed indents, coding conventions and white space edits.

Modified the c-ares completion callback function to again NOT read the
conn data when the ares handle is being taken down as then it may have
been freed already.

Introducing an internal API for handling of different async resolver
backends.

For now we directly import the Idn* symbols with the linker;
an upcoming release of OWC will have these added to the import
lib normaliz.lib, and prototypes are added to winnnls.h.

Rewritten code from a patch brought by Matteo Rocco.

Found with codespell.

Found with codespell.

Make sure that files are closed before the post quote commands run as if
they operate on the just transferred file they could otherwise easily
fail.

Patch by: Rajesh Naganathan (edited)

libcurl failed to check the correct struct for HTTPS after CONNECT was
issued to the proxy, so it didn't do the TLS handshake and subsequently
failed the connection. A regression released in 7.21.5 (introduced
around commit 8831000b).

Bug: http://curl.haxx.se/mail/lib-2011-04/0134.html
Reported by: Josue Andrade Gomes

Made it compile and work again after the code move.

Massively reduce #ifdefs all over (23 #ifdef lines less so far)
Moved conversion-specific code to non-ascii.c

It is now possible to use any combination of features without
having to 1st add makefile targets to the main makefile. The
main makefile now passes the 'mingw32-feat1-feat2' as var CFG,
and the ./[lib|src]/Makefile.m32 parses the CFG var to determine
the features to be enabled.

changed windows.h include to system header;
changed obsolete 2nd check for str_w to str_utf8 in order to catch
malloc() failure and avoid a free(NULL);
changed calls to GetLastError() to void to kill unsused var compiler
warnings;
moved one call to GetLastError() into else case so that its only
called when WideCharToMultiByte() really fails.

Provide prototype for curl_win32_idn_to_ascii();
remove wrong 3rd parameter from curl_win32_idn_to_ascii() call.

The new libcurl and command line options are now described.

Added CURLOPT_TRANSFER_ENCODING as the option to set to request Transfer
Encoding in HTTP requests (if built zlib enabled). I also renamed
CURLOPT_ENCODING to CURLOPT_ACCEPT_ENCODING (while keeping the old name
around) to reduce the confusion when we have to encoding options for
HTTP.

--tr-encoding is now the new command line option for curl to request
this, and thus I updated the test cases accordingly.

When TE: is inserted in the request, we must add a "Connection: TE" as
well to be HTTP 1.1 compliant. If a custom Connection: header is passed
in, we must use that and only append TE to it. Test case 1125 verifies
TE: + custom Connection:.

Since this struct member is used in the code to determine what and how
to decode automatically and since it is now also used for compressed
Transfer-Encodings, I renamed it to the more suitable 'auto_decoding'

Transfer-Encoding differs from Content-Encoding in a few subtle ways,
but primarily it concerns the transfer only and not the content so when
discovered to be compressed we know we have to uncompress it. There will
only arrive compressed transfers in a response after we have requested
them with the appropriate TE: header.

Test case 1122 and 1123 verify.

When going back from SSL, put the send/recv function pointers back to
the plain versions.

Bug: http://curl.haxx.se/mail/lib-2011-04/0070.html
Reported by: Mehmet Bozkurt

When checking if an existing RTSP connection is alive or not, the
checkconnection function might be called with a SessionHandle pointer
being NULL and then referenced causing a crash. This happened only using
the multi interface.

Reported by: Tinus van den Berg

Bug: http://curl.haxx.se/bug/view.cgi?id=3280739

Allow openSSL without SSL2 to be used. This fix is inspired by the fix
provided by Cristian Rodrguez.

Reported by: Cristian Rodrguez

In case a client certificate is used, invalidate SSL session cache
at the end of a session.  This forces NSS to ask for a new client
certificate when connecting second time to the same host.

Bug: https://bugzilla.redhat.com/689031

When I decided to search for a potential error with the cacert bundle it
struck me I wanted to see the full source URL in the output...

* Rename the object object directory from 'objs' to 'BCC_obj'. I feel
 it should be named properly. Ref. Makefile.Watcom where it's called
 'WC_Win32.obj'.

* Turn off these warnings to keep the build totally silent (with CBuilder-6
 that is).
  -w-inl    8026 Functions X are not expanded inline.
  -w-pia   8060 Possibly incorrect assignment
  -w-pin  8061 Initialization is only partially bracketed

I'm sure the warnings could be fixed the "proper" way or with some added
"#pragma" statements. But that just clutters the sources IMHO.

* $(MKDIR) and $(RMDIR) have been replaced with the shell-commands 'md'
 and 'rd'. When having MingW/Msys programs 'mkdir.exe' and 'rmdir.exe' in
$PATH, this confuses Borland's make and the result (the cleaning etc.) would
 not be as expected.

* Added a ".path.int = $(OBJDIR)" to tell make where the $(PREPROCESSED)
 files are. Why we need the preprocess step in the fist place is beyond me
(Yang?). But I'll leave that for now.

Also add test case 584 for the same

Bug: http://curl.haxx.se/bug/view.cgi?id=3214223

Also, fixed Curl_proxyCONNECT() stub with HTTP disabled.

Stop the abuse of CURLE_FAILED_INIT as return code for things not being
init related by introducing two new return codes:

CURLE_NOT_BUILT_IN and CURLE_UNKNOWN_OPTION

CURLE_NOT_BUILT_IN replaces return code 4 that has been obsoleted for
several years. It is used for returning error when something is
attempted to be used but the feature/option was not enabled or
explictitly disabled at build-time. Getting this error mostly means that
libcurl needs to be rebuilt.

CURLE_FAILED_INIT is now saved and used strictly for init
failures. Getting this problem means something went seriously wrong,
like a resource shortage or similar.

CURLE_UNKNOWN_OPTION is the option formerly known as
CURLE_UNKNOWN_TELNET_OPTION (and the old name is still present,
separately defined to be removed in a very distant future). This error
code is meant to be used to return when an option is given to libcurl
that isn't known. This problem would mostly indicate a problem in the
program that uses libcurl.

In my attempts to reduce #ifdefs in code, the SOCKS functions are now
macros when libcurl is built without proxy support and therefore the FTP
code could avoid some #ifs.