My additional call to Curl_pgrsUpdate() would sometimes get
called even though there's no connection (left) so a NULL pointer
would get passed, causing a segfault.

Reported-by: Steven M. Schweda

1) no need to call the progress function twice when in the
CURLM_STATE_TOOFAST state.

2) Make sure that the progress callback's return code is
acknowledged when used

As long as no error is reported, the progress function can get
called. This may be a little TOO often so we should keep an eye
on this and possibly make this conditional somehow.

Previously we only accepted the option when named
--disable-threaded-resover, which wasn't quite intended.

Reported by: Helwing Lutz

There is an implicit conversion from "unsigned long" to "long";
rounding, sign extension, or loss of accuracy may result.

Fixed by an added typecast.

Curl_fillreadbuffer()'s second argument takes an int, so
typecasting to another is a bad idea.

Older unixes want an 'int' instead of 'size_t' as the 3rd
argumment so before this change it would cause warnings such as:

There is an implicit conversion from "unsigned long" to "int";
rounding, sign extension, or loss of accuracy may result.

Signed-off-by: Diego Casorran <dcasorran@gmail.com>

Was seeing spurious SSL connection aborts using libcurl and
OpenSSL. I tracked it down to uncleared error state on the
OpenSSL error stack - patch attached deals with that.

Rough idea of problem:

Code that uses libcurl calls some library that uses OpenSSL but
don't clear the OpenSSL error stack after an error.

ssluse.c calls SSL_read which eventually gets an EWOULDBLOCK from
the OS. Returns -1 to indicate an error

ssluse.c calls SSL_get_error. First thing, SSL_get_error calls
ERR_get_error to check the OpenSSL error stack, finds an old
error and returns SSL_ERROR_SSL instead of SSL_ERROR_WANT_READ or
SSL_ERROR_WANT_WRITE.

ssluse.c returns an error and aborts the connection

Solution:

Clear the openssl error stack before calling SSL_* operation if
we're going to call SSL_get_error afterwards.

Notes:

This is much more likely to happen with multi because it's easier
to intersperse other calls to the OpenSSL library in the same
thread.

Enable OpenLDAP support for cygwin builds. This support was disabled back
in 2008 due to incompatibilities between OpenSSL and OpenLDAP headers.
cygwin's OpenSSL 0.9.8l and OpenLDAP 2.3.43 versions on cygwin 1.5.25
allow building an OpenLDAP enabled libcurl supporting back to Windows 95.

Remove non-functional CURL_LDAP_HYBRID code and references.

Jason McDonald posted bug report #3006786 when he found that the
SFTP code didn't timeout properly in several places in the code
even if a timeout was set properly.

Based on his suggested patch, I wrote a different implementation
that I think addressed the issue better and also uses the connect
timeout for the initial part of the SSH/SFTP done during the
"protocol connect" phase.

(http://curl.haxx.se/bug/view.cgi?id=3006786)