Adjusted ftpserver.pl to add support for the IMAP IDLE command

Adjusted test 660 to sync with the fix

... as it made protocol specific disconnect commands wrongly get used.

Bug: https://curl.se/mail/lib-2021-06/0024.html

Closes #7287

The execution bit of curl.h file was wrongly added:

  commit 2621025d ("curl.h: <sys/select.h> is supported by VxWorks7")

and should be removed.

Follow-up to 2621025d

 ("curl.h: <sys/select.h> is supported by VxWorks7")
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Closes #7286

Closes #7285

sendto() always returns "Socket is already connected" error on macos

Closes #7260

Move the definition of sockaddr_un struct from config-win32.h to
curl_setup.h, so that it could be shared by all build systems.

Add ADDRESS_FAMILY typedef for old mingw, now old mingw can also use
unix sockets.

Also fix the build of tests/server/sws.c on Win32 when USE_UNIX_SOCKETS
is defined.

Closes #7034

From Apples documentation on SCDynamicStoreCopyProxies, "Return Value: A
dictionary of key-value pairs that represent the current internet proxy
settings, or NULL if no proxy settings have been defined or if an error
occurred. You must release the returned value."

Failure to release the returned value of SCDynamicStoreCopyProxies can
result in a memory leak.

Source: https://developer.apple.com/documentation/systemconfiguration/1517088-scdynamicstorecopyproxies

Closes #7265

b09c8ee1 changed the function prototype. Caught by Visual Studio.

- If the UTF-8 to UTF-16 conversion fails in Windows Unicode builds then
  no longer fall back to assuming the string is in a local encoding.

Background:

Some functions in Windows Unicode builds must convert UTF-8 to UTF-16 to
pass to the Windows CRT API wide-character functions since in Windows
UTF-8 is not a valid locale (or at least 99% of the time right now).

Prior to this change if the Unicode encoding conversion failed then
libcurl would assume, for backwards compatibility with applications that
may have written their code for non-Unicode builds, attempt to convert
the string from local encoding to UTF-16.

That type of "best effort" could theoretically cause some type of
security or other problem if a string that was locally encoded was also
valid UTF-8, and therefore an unexpected UTF-8 to UTF-16 conversion
could occur.

Ref: https://github.com/curl/curl/pull/7246

Closes https://github.com/curl/curl/pull/7257

The last usage was removed in cca455a3

Closes #7280

Introducing a 'isproxy' argument to the connect function so that it
knows wether to store the time stamp or not.

Reported-by: Yongkang Huang
Fixes #7274
Closes #7274

Regression since 781864be (curl 7.77.0)

Reported-by: civodul on github
Assisted-by: Nikos Mavrogiannopoulos
Fixes #7277
Closes #7278

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7276

Closes #7273

... and move the security report section last.

Reported-by: Harry Sintonen
Closes #7270

it needs to be processed by autoconf or autoreconf, and doesn't have a
suitable shebang to be directly executed. other projects normally set
configure.ac -x.

Closes #7272

To allow users to set them when invoking configure without using
--with-debug.

Reported-by: Alex Xu
Fixes #7216
Closes #7267

Closes #7271

... by making sure the loops are only allowed to read the shutdown
traffic a limited number of times.

Reported-by: Harry Sintonen
Closes #7271

Makes test 513 work with hyper

Closes #7266

Closes #5881

Closes #6882
Closes #6884

... that were configured, just not run

Closes #7261

Unicode Windows builds use UTF-8 strings internally in libcurl,
so make sure to call the UTF-8 flavour of the libidn2 API. Also
document that Windows builds with libidn2 and UNICODE do expect
CURLOPT_URL as an UTF-8 string.

Reported-by: dEajL3kA on github
Assisted-by: Jay Satiro
Reviewed-by: Marcel Raad
Closes #7246
Fixes #7228

They were never officially allowed and slipped in only due to sloppy
parsing. Spaces (ascii 32) should be correctly encoded (to %20) before
being part of a URL.

The new flag bit CURLU_ALLOW_SPACE when a full URL is set, makes libcurl
allow spaces.

Updated test 1560 to verify.

Closes #7073

... and bump to version 7.78.0 for the next planned release.

- Document that HTTP/2 multiplexing is supported by the curl tool when
  parallel transfers are used.

Supported since 7.66.0 via --parallel, but the doc wasn't updated.

Closes https://github.com/curl/curl/pull/7259