Visual C++ now complains about implicitly casting time_t (64-bit) to
long (32-bit). Fix this by changing some variables from long to time_t,
or explicitly casting to long where the public interface would be
affected.

Closes #1131

When reusing a connection, make sure the unix domain
socket option matches.

- Improve performance by using a huge HTTP/2 window size.

Bug: https://github.com/curl/curl/issues/1102


Reported-by:  <afrind@users.noreply.github.com>
Assisted-by: Tatsuhiro Tsujikawa

- In Curl_http2_switched don't call memcpy when src is NULL.

Curl_http2_switched can be called like:

Curl_http2_switched(conn, NULL, 0);

.. and prior to this change memcpy was then called like:

memcpy(dest, NULL, 0)

.. causing address sanitizer to warn:

http2.c:2057:3: runtime error: null pointer passed as argument 2, which
is declared to never be null

Reviewed-by: Nick Zitzmann

Closes #1105

Now Curl_rand() is made to fail if it cannot get the necessary random
level.

Changed the proto of Curl_rand() slightly to provide a number of ints at
once.

Moved out from vtls, since it isn't a TLS function and vtls provides
Curl_ssl_random() for this to use.

Discussion: https://curl.haxx.se/mail/lib-2016-11/0119.html

Blah, I accidentally wrote size_t instead of time_t for two variables.

Reported-by: Dave Reisner

... as long is still 32bit on modern 64bit windows machines, while
time_t is generally 64bit.

Previously, the [host] part was just ignored which made libcurl accept
strange URLs misleading users. like "file://etc/passwd" which might've
looked like it refers to "/etc/passwd" but is just "/passwd" since the
"etc" is an ignored host name.

Reported-by: Mike Crowe
Assisted-by: Kamil Dudka

1.1.0+ does more of this by itself so we can avoid extra processing this
way.

and remove RAND_screen from configure since nothing is using that
function

Discussed: https://curl.haxx.se/mail/lib-2016-11/0087.html

Now I've managed to negotiate TLS 1.3 with https://enabled.tls13.com/ when
using boringssl.

- Fix GnuTLS code for CURL_SSLVERSION_TLSv1_2 that broke when the
TLS 1.3 support was added in 6ad3add6.

- Homogenize across code for all backends the error message when TLS 1.3
is not available to "<backend>: TLS 1.3 is not yet supported".

- Return an error when a user-specified ssl version is unrecognized.

---

Prior to this change our code for some of the backends used the
'default' label in the switch statement (ie ver unrecognized) for
ssl.version and treated it the same as CURL_SSLVERSION_DEFAULT.

Bug: https://curl.haxx.se/mail/lib-2016-11/0048.html
Reported-by: Kamil Dudka

If SPNEGO fails, cleanup the negotiate handle right away.

Fixes #1115

Signed-off-by: Isaac Boukris <iboukris@gmail.com>
Reported-by: ashman-p

It would always use precision 1 instead of reading it from the argument
list as intended.

Reported-by: Ray Satiro

Bug: #1113

... with nss-3.26.0 and newer

Reported-by: Daniel Stenberg

BoringSSL supports TLSv1.3 already, but these changes don't seem to be anough
to get it working.

Revert the change from ce8d0948 but use the new function

Reported-by: Kamil Dudka
Bug: https://github.com/curl/curl/commit/ce8d09483eea2fcb1b50e323e1a8ed1f3613b2e3#commitcomment-19666146

Fully implemented with the NSS backend only for now.

Reviewed-by: Ray Satiro

... but make sure we use at least TLSv1.0 according to libcurl API

Reported-by: Cure53
Reviewed-by: Ray Satiro

We're mostly saying just "curl" in lower case these days so here's a big
cleanup to adapt to this reality. A few instances are left as the
project could still formally be considered called cURL.

Previously, we just ignored "Connection" header field.  But HTTP/2
specification actually prohibits few more header fields.  This commit
ignores all of them so that we don't send these bad header fields.

Bug: https://curl.haxx.se/mail/archive-2016-10/0033.html
Reported-by: Ricki Hirner

Closes https://github.com/curl/curl/pull/1092

- Call Curl_initinfo on init and duphandle.

Prior to this change the statistical and informational variables were
simply zeroed by calloc on easy init and duphandle. While zero is the
correct default value for almost all info variables, there is one where
it isn't (filetime initializes to -1).

Bug: https://github.com/curl/curl/issues/1103
Reported-by: Neal Poole

Regression added in 62a8095e

Reported-by: Tony Kelman

Discussed in #1087

Follow-up to 502acba2

Coverity CID 1374359 pointed out the unused result value.

Coverity CID 1374358

follow-up to 46133aa5

...to use the public function curl_strnequal(). This isn't ideal because
it adds extra overhead to any internal calls to checkprefix.

follow-up to 95bd2b3e

As they are after all part of the public API. Saves space and reduces
complexity. Remove the strcase defines from the curlx_ family.

Suggested-by: Dan Fandrich
Idea: https://curl.haxx.se/mail/lib-2016-10/0136.html

follow-up to 811a693b

This should fix the "warning: 'curl_strequal' redeclared without
dllimport attribute: previous dllimport ignored" message and subsequent
link error on Windows because of the missing CURL_EXTERN on the
prototype.

This is a followup to commit 811a693b

Fix compile break from 811a693b

Fix bug from 811a693b

Mistake brought by 9c91ec77