This allows the compiler to pack and align the structs better in
memory. For a rather feature-complete build on x86_64 Linux, gcc 8.1.2
makes the Curl_easy struct 4.9% smaller. From 6312 bytes to 6000.

Removed an unused struct field.

No functionality changes.

Closes #3610

Closes #3616

Closes #3611

Follow-up to 180501cb

Reported-by: Marcel Raad
Fixes #3609
Closes #3620

Switch all Visual Studio 2015 builds to Visual Studio 2017. It's not a
moving target anymore as the last update, Update 9, has been released.

Closes https://github.com/curl/curl/pull/3606

The Visual Studio 2017 image has Visual Studio 2015 and 2017 installed.

Closes https://github.com/curl/curl/pull/3606

Currently, we're using the default Visual Studio 2015 image for
everything.

Closes https://github.com/curl/curl/pull/3606

Instead of using a fixed 256 byte buffer in the connectdata struct.

In my build, this reduces the size of the connectdata struct by 11.8%,
from 2160 to 1904 bytes with no functionality or performance loss.

This also fixes a bug in schannel's Curl_verify_certificate where it
called Curl_sspi_strerror when it should have called Curl_strerror for
string from GetLastError. the only effect would have been no text or the
wrong text being shown for the error.

Co-authored-by: Jay Satiro

Closes #3612

Regression brought by a52e46f3 (shipped in 7.63.0)

Closes #3613

It's passing now.

Closes https://github.com/curl/curl/pull/3615

Remove the Visual Studio 2012 and 2013 builds as they add little value.

Ref: https://github.com/curl/curl/pull/3606
Closes https://github.com/curl/curl/pull/3614

Closes #3591

- Add an additional check for LDAP that also checks for OpenSSL since
  on AIX those libraries may be required to link LDAP properly.

Fixes https://github.com/curl/curl/issues/3595
Closes https://github.com/curl/curl/pull/3596

Add support for Ephemeral elliptic curve Diffie-Hellman key exchange
algorithm option when selecting ciphers. This became available on the
Win10 SDK.

Closes https://github.com/curl/curl/pull/3608

Failing to do so would make the CURLINFO_TOTAL_TIME timeout to not get
updated correctly and could end up getting reported to the application
completely wrong (way too small).

Reported-by: accountantM on github
Fixes #3602
Closes #3605

From within the timer callbacks. Recursive is problematic for several
reasons. They should still work, but this way the examples and the
documentation becomes simpler. I don't think we need to encourage
recursive calls.

Discussed in #3537
Closes #3601

The macro itself has been removed in commit
11974ac8.

Closes https://github.com/curl/curl/pull/3604

since wolfSSL PR https://github.com/wolfSSL/wolfssl/pull/717 (shipped in
wolfSSL 3.10.2 and later) it sends these curves by default already.

Pointed-out-by: David Garske

Closes #3599

and the two remaining #ifdefs for it

Closes #3600

- Split off connection shutdown procedure from Curl_disconnect into new
  function conn_shutdown.

- Change the shutdown procedure to close the sockets before
  disassociating the transfer.

Prior to this change the sockets were closed after disassociating the
transfer so SOCKETFUNCTION wasn't called since the transfer was already
disassociated. That likely came about from recent work started in
Jan 2019 (#3442) to separate transfers from connections.

Bug: https://curl.haxx.se/mail/lib-2019-02/0101.html
Reported-by: Pavel Löbl

Closes https://github.com/curl/curl/issues/3597
Closes https://github.com/curl/curl/pull/3598

As seen in the MinGW autobuilds. Caused by commit
f26bc29c.

Suggested-by: Nicolas Grekas

... and remove it from the dist tarball. It has served its time, it
barely gets updated anymore and "everything curl" is now convering all
this document once tried to include, and does it more and better.

In the compressed scenario, this removes ~15K data from the binary,
which is 25% of the -M output.

It remains in the git repo for now for as long as the web site builds a
page using that as source. It renders poorly on the site (especially for
mobile users) so its not even good there.

Closes #3587

RFC 7540 says we should verify that the push is for an "authoritative"
server. We make sure of this by only allowing push with an :athority
header that matches the host that was asked for in the URL.

Fixes #3577
Reported-by: Nicolas Grekas
Bug: https://curl.haxx.se/mail/lib-2019-02/0057.html
Closes #3581

The variable wasn't properly reset within the loop and thus could remain
set for sockets that hadn't been set before and miss notifying the app.

This is a follow-up to 4c35574b (shipped in curl 7.64.0)

Reported-by: buzo-ffm on github
Detected-by: Jan Alexander Steffens
Fixes #3585
Closes #3589

and make CONNECT_ONLY conections never reuse any existing ones either.

Reported-by: Pavel Löbl
Bug: https://curl.haxx.se/mail/lib-2019-02/0064.html
Closes #3586

Reported-by: Marcel Raad
Fixes #3576
Closes #3583

- rename 'n' to buflen in functions, and use size_t for them. Don't pass
  in negative buffer lengths.

- move most function comments to above the function starts like we use
  to

- remove several unnecessary typecasts (especially of NULL)

Reviewed-by: Patrick Monnerat
Closes #3582

[ci skip]

Previously the function would edit the provided header in-place when a
semicolon is used to signify an empty header. This made it impossible to
use the same set of custom headers in multiple threads simultaneously.

This approach now makes a local copy when it needs to edit the string.

Reported-by: d912e3 on github
Fixes #3578
Closes #3579

Reported-by: Björn Stenberg <bjorn@haxx.se>
Closes #3584

Although safe in this context, using a single char as an array may
cause invalid accesses to adjacent memory locations.

Detected by Coverity.

To avoid NULL pointer dereferences etc in the case of problems.

Closes #3580

- Change the behavior of win32_init so that the required initialization
  procedures are not affected by CURL_GLOBAL_WIN32 flag.

libcurl via curl_global_init supports initializing for win32 with an
optional flag CURL_GLOBAL_WIN32, which if omitted was meant to stop
Winsock initialization. It did so internally by skipping win32_init()
when that flag was set. Since then win32_init() has been expanded to
include required initialization routines that are separate from
Winsock and therefore must be called in all cases. This commit fixes
it so that CURL_GLOBAL_WIN32 only controls the optional win32
initialization (which is Winsock initialization, according to our doc).

The only users affected by this change are those that don't pass
CURL_GLOBAL_WIN32 to curl_global_init. For them this commit removes the
risk of a potential crash.

Ref: https://github.com/curl/curl/pull/3573

Fixes https://github.com/curl/curl/issues/3313
Closes https://github.com/curl/curl/pull/3575

The draft-ietf-httpbis-rfc6265bis-02 draft, specify a set of prefixes
and how they should affect cookie initialization, which has been
adopted by the major browsers. This adds support for the two prefixes
defined, __Host- and __Secure, and updates the testcase with the
supplied examples from the draft.

Closes #3554
Reviewed-by: Daniel Stenberg <daniel@haxx.se>

If mbedtls_ssl_get_session() fails, it may still have allocated
memory that needs to be freed to avoid leaking. Call the library
API function to release session resources on this errorpath as
well as on Curl_ssl_addsessionid() errors.

Closes: #3574
Reported-by: Michał Antoniak <M.Antoniak@posnet.com>
Reviewed-by: Daniel Stenberg <daniel@haxx.se>