When looping in this function and checking for the timeout being
expired, it was not updating the reference time when calculating the
timediff since previous round which made it think each subsequent loop
to have taken longer than it actually did.

I also modified the function to use the generic Curl_timeleft() function
instead of the custom logic.

Bug: http://curl.haxx.se/bug/view.cgi?id=3112579

When send() and recv() fail, we now store the errno value to allow the
app to access it.

Bug: http://curl.haxx.se/bug/view.cgi?id=3128121
Reported by: Yuri

- Show address string from proper buffer in case of connection failure.

- Try next address when inet_ntop() fails.

Reinstate IPV6 build variable that got removed.

Failed to commit this file changes along with the others.

warning C4146: unary minus operator applied to unsigned type, result still unsigned

Ensure that spurious results from system's getaddrinfo() ares not propagated
by Curl_getaddrinfo_ex() into the library.

Also ensure that the ai_addrlen member of Curl_getaddrinfo_ex()'s output linked
list of Curl_addrinfo structures has appropriate family-specific address size.

... not the proxy port.  It makes no difference unless a proxy is used.

Winsock builds clobber some errno.h defines in setup_once.

On Windows, translate WSAGetLastError() to errno values as GNU
TLS does it internally, too. This is necessary because send() and
recv() on Windows don't set errno when they fail but GNU TLS
expects a proper errno value.

Bug: http://curl.haxx.se/bug/view.cgi?id=3110991

When no timeout is set, we call the socket_ready function with a timeout
value of 0 during handshake, which makes it loop too much/fast in this
function. It also made this function return CURLE_OPERATION_TIMEDOUT
wrongly on a slow handshake.

However, the particular bug report that highlighted this problem is not
solved by this fix, as this fix only makes the more proper error get
reported instead.

Bug: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=594150
Reported by: Johannes Ernst

This makes it easier to spot the enum values from the variables.
Removed some unneeded DEBUGASSERT added in the previous commit.

While changing Curl_sec_read_msg to accept an enum protection_level
instead of an int, I went ahead and fixed the usage of the associated
fields.

Some code was assuming that prot_clear == 0. Fixed those to use the
proper value. Added assertions prior to any code that would set the
protection level.

This is the advised way of checking for errors in the GSS-API RFC.
Also added some '\n' to the error message so that they are not mixed
with other outputs.

init is expecting app_data. Passing it the struct connecdata would make
us crash later.