cURL 7.70.0

What's new in this version:

Changes:
- curl: add --ssl-revoke-best-effort to allow a "best effort" revocation check
- mqtt: add new experimental protocol
- schannel: add "best effort" revocation check option: CURLSSLOPT_REVOKE_BEST_EFFORT
- writeout: support to generate JSON output with '%{json}'

Bugfixes:
- appveyor: add Unicode winbuild jobs
- appveyor: completely disable tests that fail to timeout early
- appveyor: show failed tests in log even if test is ignored
- appveyor: sort builds by type and add two new variants
- appveyor: turn disabled tests into ignored result tests
- appveyor: use random test server ports based upon APPVEYOR_API_URL
- build: fixed build for systems with select() in unistd.h
- buildconf: avoid using tempfile when removing files
- checksrc: warn on obvious conditional blocks on the same line as if()
- CI-fuzz: increase fuzz time to 40 minutes
- ci/tests: fix Azure Pipelines not running Windows containers
- CI: add build with ngtcp2 + gnutls on Travis CI
- CI: bring GitHub Actions fuzzing job in line with macOS jobs
- CI: migrate macOS jobs from Azure and Travis CI to GitHub Actions
- CI: remove default Ubuntu build from GitHub Actions
- cirrus: no longer ignore test 504 which is working again
- cirrus: re-enable the FreeBSD 13 CI builds
- cleanup: insert newline after if() conditions
- cmake: add aliases so exported target names are available in tree
- cmake: add CMAKE_MSVC_RUNTIME_LIBRARY
- cmake: add support for building with wolfSSL
- cmake: Avoid MSVC C4273 warnings in send/recv checks
- cmdline: fix handling of OperationConfig linked list (--next)
- compressed.d: stress that the headers are not modified
- config: remove all defines of HAVE_DES_H
- configure: convert -I to -isystem as a last step
- configure: document 'compiler_num' for gcc
- configure: don't check for Security.framework when cross-compiling
- configure: fix -pedantic-errors for GCC 5 and later
- configure: remove use of -vec-report0 from CFLAGS with icc
- connect: happy eyeballs cleanup
- connect: store connection info for QUIC connections
- copyright: fix out-of-date copyright ranges and missing headers
- curl-functions.m4: remove inappropriate AC_REQUIRE
- curl.h: remnove CURL_VERSION_ESNI. Never supported nor documented
- curl.h: update comment typo
- curl: allow both --etag-compare and --etag-save with same file name
- curl_setup: define _WIN32_WINNT_[OS] symbols
- CURLINFO_CONDITION_UNMET: return true for 304 http status code
- CURLINFO_NUM_CONNECTS: improve accuracy
- CURLOPT_WRITEFUNCTION.3: add inline example and new see-also
- dist: add mail-rcpt-allowfails.d to the tarball
- docs/make: generate curl.1 from listed files only
- docs: add warnings about FILE: URLs on Windows
- easy: fix curl_easy_duphandle for builds missing IPv6 that use c-ares
- examples/sessioninfo.c: add include to fix compiler warning
- github actions: run when pushed to master or */ci + PRs
- gnutls: bump lowest supported version to 3.1.10
- gnutls: Don't skip really long certificate fields
- gnutls: ensure TLS 1.3 when SRP isn't requested
- gopher: check remaining time left during write busy loop
- gskit: use our internal select wrapper for portability
- http2: Fix erroneous debug message that h2 connection closed
- http: don't consider upload done if the request isn't completely sent off
- http: free memory when Alt-Used header creation fails due to OOM
- lib/mk-ca-bundle: skip empty certs
- lib670: use the same Win32 API check as all other lib tests
- lib: fix typos in comments and errormessages
- lib: never define CURL_CA_BUNDLE with a getenv
- libcurl-multi.3: added missing full stop
- libssh: avoid options override by configuration files
- libssh: Use new ECDSA key types to check known hosts
- mailmap: fixup a few author names/fields
- Makefile.m32: Improve windres parameter compatibility
- Makefile: run the cd commands in a subshell
- memdebug: don't log free(NULL)
- mime: properly check Content-Type even if it has parameters
- multi-ssl: reset the SSL backend on `Curl_global_cleanup()`
- multi: improve parameter check for curl_multi_remove_handle
- nghttp2: 1.12.0 required
- ngtcp2: update to git master for the key installation API change
- nss: check for PK11_CreateDigestContext() returning NULL
- openssl: adapt to functions marked as deprecated since version 3
- OS400: update strings for ccsid-ifier (fixes the build)
- output.d: quote the URL when globbing
- packages: add OS400/chkstrings.c to the dist
- RELEASE-PROCEDURE.md: run the copyright.pl script!
- Revert "file: on Windows, refuse paths that start with \"
- runtests: always put test number in servercmd file
- runtests: provide nicer errormsg when protocol "dump" file is empty
- schannel: Fix blocking timeout logic
- schannel: support .P12 or .PFX client certificates
- scripts/release-notes.pl: add helper script for RELEASE-NOTES maintenance
- select: make Curl_socket_check take timediff_t timeout
- select: move duplicate select preparation code into Curl_select
- select: remove typecast from SOCKET_WRITABLE/READABLE macros
- server/getpart: make the "XML-parser" stricter
- server/resolve: remove AI_CANONNAME to make macos tell the truth
- smtp: set auth correctly
- sockfilt: add logmsg output to select_ws_wait_thread on Windows
- sockfilt: fix broken pipe on Windows to be ready in select_ws
- sockfilt: fix handling of ready closed sockets on Windows
- sockfilt: fix race-condition of waiting threads and event handling
- socks: Fix blocking timeout logic
- src: Remove C99 constructs to ensure C89 compliance
- SSLCERTS.md: Fix example code for setting CA cert file
- test1148: tolerate progress updates better (again)
- test1154: set a proper name
- test1177: verify that all the CURL_VERSION_ bits are documented
- test1566: verify --etag-compare that gets a 304 back
- test1908: avoid using fixed port number in test data
- test2043: use revoked.badssl.com instead of revoked.grc.com
- test2100: fix static port instead of dynamic value being used
- tests/data: fix some XML formatting issues in test cases
- tests/FILEFORMAT: converted to markdown and extended
- tests/server/util.c: use curl_off_t instead of long for pid
- tests: add %NOLISTENPORT and use it
- tests: add Windows compatible pidwait like pidkill and pidterm
- tests: fix conflict between Cygwin/msys and Windows PIDs
- tests: introduce preprocessed test cases
- tests: make Python-based servers compatible with Python 2 and 3
- tests: make runtests check that disabled tests exists
- tests: move pingpong server to dynamic listening port
- tests: remove python_dependencies for smbserver from our tree
- tests: run the RTSP test server on a dynamic port number
- tests: run the SOCKS test server on a dynamic port number
- tests: run the sws server on "any port"
- tests: run the TFTP test server on a dynamic port number
- tests: use Cygwin/msys PIDs for stunnel and sshd on Windows
- tls: remove the BACKEND define kludge from most backends
- tool: do not declare functions with Curl_ prefix
- tool_operate: fix add_parallel_transfers when more are in queue
- transfer: cap retries of "dead connections" to 5
- transfer: Switch PUT to GET/HEAD on 303 redirect
- travis: bump the wolfssl CI build to use 4.4.0
- travis: update the ngtcp2 build to use the latest OpenSSL patch
- url: allow non-HTTPS altsvc-matching for debug builds
- version: add 'cainfo' and 'capath' to version info struct
- version: increase buffer space for ssl version output
- version: skip idn2_check_version() check and add precaution
- vquic: add support for GnuTLS backend of ngtcp2
- vtls: fix ssl_config memory-leak on out-of-memory
- warnless: remove code block for icc that didn't work
- windows: enable UnixSockets with all build toolchains
- windows: suppress UI in all CryptAcquireContext() calls