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

Having an open brace without a closing brace caused a segfault.

Having a closing brace too many caused a silent error to occur, which
caused curl to bail out and return an error code but no error message
was shown. It does now!

All error message outputs no longer wrongly get _two_ newlines written
after the error message.

Reported by: Vlad Ureche
Bug: http://curl.haxx.se/bug/view.cgi?id=3083942

The invocation of autoconf's AC_PATH_PROG( ) is not quite right for
finding curl-config. This fix corrects the negative case (where
curl-config is not found).

"261 - configure and libidn" is removed from the list since Julien
Chaffraix tried to repeat it but failed and the reporter did not return
to provide further details.

Reported by: Lyndon Hill
Bug: http://curl.haxx.se/mail/lib-2010-07/0029.html

The macro provides a --with-libcurl option that expects a PREFIX to be
specified and not actually a "directory" in which libcurl will be found.
This now spells that out more clearly.

Reported by: Dan Locks
Bug: http://curl.haxx.se/bug/view.cgi?id=3079891

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.

"3076808 Requests fail silently following a 416 error" done

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

This delays between write operations, hopefully making it easier
to spot problems where libcurl doesn't flush the socket properly
before waiting for the next response.

The issue named "266 - Bug in ftp_nextconnect?" was deemed to not be a
bug and instead resulted in clarified docs.

Make it explicit that setting CURLOPT_DIRLISTONLY to 1 will make libcurl
to list the directory.

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

I haven't read any really convincing arguments for adding it

all multi and hiper examples:

* don't loop curl_multi_perform calls, that was <7.20.0 style, currently
  the exported multi functions will not return CURLM_CALL_MULTI_PERFORM

all hiper examples:
* renamed check_run_count to check_multi_info
* don't  compare current running handle count with previous value, this
  was the wrong way to check for finished requests, simply call
  curl_multi_info_read
* it's also safe to call curl_multi_remove_handle inside the
  curl_multi_info_read loop.

ghiper.c:
* replaced curl_multi_socket (that function is marked as obsolete) calls
  with curl_multi_socket_action calls (as in hiperfifo.c and
  evhiperfifo.c)

ghiper.c and evhiperfifo.c:
* be smart as hiperfifo.c, don't do uncessary curl_multi_* calls in
  new_conn and main

As we're already in feature freeze, I pushed the feature onwards.

OS400 compile script in test dir updated for chkhostname.

Remove a leak seen on Kerberos/MIT (gss_OID is copied internally and
we were leaking it). Now we just pass NULL as advised in RFC2744.

|tmp| was never set back to buf->data.

Cleaned up Curl_sec_end to take into account failure in Curl_sec_login
(where conn->mech would be NULL but not conn->app_data or
conn->in_buffer->data).

The current implementation would make us send wrong data on a closed
socket. We don't buffer our data so the method can be safely removed.

Following a change in the way socket handler are registered, the custom
recv and send method were conditionaly registered.
We need to register them everytime to handle the ftp security
extensions.

Re-added the clear text handling in sec_recv.

Curl_sec_login was returning the opposite result that the code in ftp.c
was expecting. Simplified the return code (using a CURLcode) so to see
more clearly what is going on.

They are not automatically added and make the output of the verbose
mode a lot more readable.

My use of va_args was completely wrong. Fixed the usage so that
we send the right commands!

According to RFC3986 section 2.3 the letters -, ., _ and ~ should not be
percent-encoded.

Reported by: Miguel Diaz
Bug: http://curl.haxx.se/mail/lib-2010-09/0227.html