There is information about the compiled-in SSL backends that is really
no concern of any code other than the SSL backend itself, such as which
function (if any) implements SHA-256 summing.

And there is information that is really interesting to the user, such as
the name, or the curl_sslbackend value.

Let's factor out the latter into a publicly visible struct. This
information will be used in the upcoming API to set the SSL backend
globally.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

... to get the event/revent defines that might be used for the poll
struct.

Reported-by: Michael Smith
Fixes #1828
Closes #1833

Reported-by: John David Anglin
Bug: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=872502#10

... regression since issue #1774 (commit 10b3df10) since obviously
some older gcc doesn't know __powerpc__ while some newer doesn't know
__ppc__ ...

Fixes #1797
Closes #1798
Reported-by: Ryan Schmidt

... as they're not used externally and internally we check for the sizes
already in configure etc.

Closes #1767

The required low-level logic was already available as part of
`libssh2` (via `LIBSSH2_FLAG_COMPRESS` `libssh2_session_flag()`[1]
option.)

This patch adds the new `libcurl` option `CURLOPT_SSH_COMPRESSION`
(boolean) and the new `curl` command-line option `--compressed-ssh`
to request this `libssh2` feature. To have compression enabled, it
is required that the SSH server supports a (zlib) compatible
compression method and that `libssh2` was built with `zlib` support
enabled.

[1] https://www.libssh2.org/libssh2_session_flag.html

Ref: https://github.com/curl/curl/issues/1732
Closes https://github.com/curl/curl/pull/1735

Closes #1774

Fixes #1752

The long list of architectures in include/curl/system.h is annoying to
maintain, and needs to be extended for each and every architecture to
support.

Instead, let's rely on the __SIZEOF_LONG__ define of the gcc compiler
(we are in the GNUC condition anyway), which tells us if long is 4
bytes or 8 bytes.

This fixes the build of libcurl 7.55.0 on architectures such as
OpenRISC or ARC.

Closes #1766

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

... to avoid compiler warnings if the user doesn't want
WIN32_LEAN_AND_MEAN.

Make sure to always define WIN32_LEAN_AND_MEAN before including any
Windows headers to avoid pulling in unnecessary headers. This avoids
unnecessary macro clashes and compiler warnings.

Ref: https://github.com/curl/curl/issues/1562
Closes https://github.com/curl/curl/pull/1672

If libcurl was built with GSS-API support, it unconditionally advertised
GSS-API authentication while connecting to a SOCKS5 proxy.  This caused
problems in environments with improperly configured Kerberos: a stock
libcurl failed to connect, despite libcurl built without GSS-API
connected fine using username and password.

This commit introduces the CURLOPT_SOCKS5_AUTH option to control the
allowed methods for SOCKS5 authentication at run time.

Note that a new option was preferred over reusing CURLOPT_PROXYAUTH
for compatibility reasons because the set of authentication methods
allowed by default was different for HTTP and SOCKS5 proxies.

Bug: https://curl.haxx.se/mail/lib-2017-01/0005.html
Closes https://github.com/curl/curl/pull/1454

Reported-by: Neil Kolban
Fixes: 1598

... and CURLOPT_REQUEST_TARGET instead of CURLOPT_STRIP_PATH_SLASH.

This option instead provides the full "alternative" target to use in the
request, instead of extracting the path from the URL.

Test 1298 and 1299 updated accordingly.

Idea-by: Evert Pot
Suggestion: https://daniel.haxx.se/blog/2017/06/19/options-with-curl/comment-page-1/#comment-18373

Closes #1593

typecheck-gcc expected curl_socket_t instead of curl_off_t arguments
for CURLINFO_OFF_T. Detected by test1521, unfortunately only when run
locally.

Closes https://github.com/curl/curl/pull/1592

... to enable sending "OPTIONS *" which wasn't possible previously.

This option currently only works for HTTP.

Added test cases 1298 + 1299 to verify

Fixes #1280
Closes #1462

This change introduces new alternatives for the existing six
curl_easy_getinfo() options that return sizes or speeds as doubles. The
new versions are named like the old ones but with an appended '_T':

CURLINFO_CONTENT_LENGTH_DOWNLOAD_T
CURLINFO_CONTENT_LENGTH_UPLOAD_T
CURLINFO_SIZE_DOWNLOAD_T
CURLINFO_SIZE_UPLOAD_T
CURLINFO_SPEED_DOWNLOAD_T
CURLINFO_SPEED_UPLOAD_T

Closes #1511

CURLSYS_PULL_WS2TCPIP_H got renamed to CURL_PULL_WS2TCPIP_H in commit
73a2fcea.

Rely entirely on curl/system.h now.

Introduced in Aug 2008 with commit 14240e9e. Now gone.

Fixes #1456

... and update the certinfo.c example accordingly.

Fixes https://github.com/curl/curl/issues/846

... so that they get the required "struct curl_tlssessioninfo **"
arguments.

Fixes #1524

... and support and additional "security patched" date for those who
enhance older versions that way. Pass on the define CURL_PATCHSTAMP with
a date for that.

Building with non-release headers shows the date as [unreleased].

Also: this changes the date format generated in the curlver.h file to be
"YYYY-MM-DD" (no name of the day or month, no time, no time zone) to
make it easier on the eye and easier to parse. Example (new) date
string: 2017-05-09

Suggested-by: Brian Childs

Closes #1474

Closes https://github.com/curl/curl/pull/1452

Closes https://github.com/curl/curl/pull/1452

Info values starting with CURLINFO_SOCKET expect a curl_socket_t, not a
curl_slist argument.

This fixes the following GCC warning when building the examples with
--enable-optimize:

../../include/curl/typecheck-gcc.h:126:42: warning: call to
‘_curl_easy_getinfo_err_curl_slist’ declared with attribute warning:
curl_easy_getinfo expects a pointer to 'struct curl_slist *' for this
info [enabled by default]
sendrecv.c:90:11: note: in expansion of macro ‘curl_easy_getinfo’
res = curl_easy_getinfo(curl, CURLINFO_ACTIVESOCKET, &sockfd);

Closes https://github.com/curl/curl/pull/1447

All the callbacks passed to curl_easy_setopt are defined as function
pointers. The possibility to pass both functions and function pointers
was handled for the callbacks that typecheck-gcc.h defined as
compatible, but not for the public callback types themselves.

This makes all compatible callback types defined in typecheck-gcc.h
function pointers too and checks all functions uniformly with
_curl_callback_compatible, which handles both functions and function
pointers.

A symptom of the problem was a warning in tool_operate.c with
--disable-libcurl-option and without --enable-debug as that file
passes the callback functions to curl_easy_setopt directly.

Fixes https://github.com/curl/curl/issues/1403
Closes https://github.com/curl/curl/pull/1404

Reported-by: Marcel Raad
Fixes #1408
Closes #1409

Closes #1397

Triggered a test failure on test 1541 for the build known as
"Linux 4.4 i686 tcc 0.9.26 glibc 2.20"

system.h is aimed to replace curlbuild.h at a later point in time when
we feel confident system.h works sufficiently well.

curl/system.h is currently used in parallel with curl/curlbuild.h

curl/system.h determines a data sizes, data types and include file
status based on available preprocessor defines instead of getting
generated at build-time. This, in order to avoid relying on a build-time
generated file that makes it complicated to do 32 and 64 bit bields from
the same installed set of headers.

Test 1541 verifies that system.h comes to the same conclusion that
curlbuild.h offers.

Closes #1373

Closes #1356

- Add new option CURLOPT_SUPPRESS_CONNECT_HEADERS to allow suppressing
  proxy CONNECT response headers from the user callback functions
  CURLOPT_HEADERFUNCTION and CURLOPT_WRITEFUNCTION.

- Add new tool option --suppress-connect-headers to expose
  CURLOPT_SUPPRESS_CONNECT_HEADERS and allow suppressing proxy CONNECT
  response headers from --dump-header and --include.

Assisted-by: Jay Satiro
Assisted-by:  <CarloCannas@users.noreply.github.com>
Closes https://github.com/curl/curl/pull/783

...due to the newly added CURL_SSLVERSION_MAX_* functionality