Changes in 7.56.0 - October 4 2017

Changes:

• curl: enable compression for SCP/SFTP with --compressed-ssh
• libcurl: enable compression for SCP/SFTP with CURLOPT_SSH_COMPRESSION
• vtls: added dynamic changing SSL backend with curl_global_sslset()
• new MIME API, curl_mime_init() and friends
• openssl: initial SSLKEYLOGFILE implementation

Bugfixes:

• FTP: zero terminate the entry path even on bad input
• examples/ftpuploadresume.c: use portable code
• runtests: match keywords case insensitively
• travis: build the examples too
• strtoofft: reduce integer overflow risks globally
• zsh.pl: produce a working completion script again
• cmake: remove dead code for CURL_DISABLE_RTMP
• progress: Track total times following redirects
• configure: fix --disable-threaded-resolver
• cmake: remove dead code for DISABLED_THREADSAFE
• configure: fix clang version detection
• darwinssi: fix error: variable length array used
• travis: add metalink to some osx builds
• configure: check for __builtin_available() availability
• http_proxy: fix build error for CURL_DOES_CONVERSIONS
• examples/ftpuploadresume: checksrc compliance
• ftp: fix CWD when doing multicwd then nocwd on same connection
• system.h: remove all CURL_SIZEOF_* defines
• http: Don't wait on CONNECT when there is no proxy
• system.h: check for __ppc__ as well
• http2_recv: return error better on fatal h2 errors
• scripts/contri*sh: use "git log --use-mailmap"
• tftp: fix memory leak on too long filename
• system.h: fix build for hppa
• cmake: enable picky compiler options with clang and gcc
• makefile.m32: add support for libidn2
• curl: turn off MinGW CRT's globbing
• request-target.d: mention added in 7.55.0
• curl: shorten and clean up CA cert verification error message
• imap: support PREAUTH
• CURLOPT_USERPWD.3: see also CURLOPT_PROXYUSERPWD
• examples/threaded-ssl: mention that this is for openssl before 1.1
• winbuild: fix embedded manifest option
• tests: Make sure libtests & unittests call curl_global_cleanup()
• system.h: include sys/poll.h for AIX
• darwinssl: handle long strings in TLS certs
• strtooff: fix build for systems with long long but no strtoll
• asyn-thread: Improved cleanup after OOM situations
• HELP-US.md: "How to get started helping out in the curl project"
• curl.h: CURLSSLBACKEND_WOLFSSL used wrong value
• unit1301: fix error message on first test
• ossfuzz: moving towards the ideal integration
• http: fix a memory leakage in checkrtspprefix()
• examples/post-callback: stop returning one byte at a time
• schannel: return CURLE_SSL_CACERT on failed verification
• MAIL-ETIQUETTE: added "1.9 Your emails are public"
• http-proxy: treat all 2xx as CONNECT success
• openssl: use OpenSSL's default ciphers by default
• runtests.pl: support attribute "nonewline" in part verify/upload
• configure: remove --enable-soname-bump and SONAME_BUMP
• travis: add c-ares enabled builds linux + osx
• vtls: fix WolfSSL 3.12 build problems
• http-proxy: when not doing CONNECT, that phase is done immediately
• configure: fix curl_off_t check's include order
• configure: use -Wno-varargs on clang 3.9[.X] debug builds
• rtsp: do not call fwrite() with NULL pointer FILE *
• mbedtls: enable CA path processing
• travis: add build without HTTP/SMTP/IMAP
• checksrc: verify more code style rules
• HTTP proxy: on connection re-use, still use the new remote port
• tests: add initial gssapi test using stub implementation
• rtsp: Segfault when using WRITEDATA
• docs: clarify the CURLOPT_INTERLEAVE* options behavior
• non-ascii: use iconv() with 'char **' argument
• server/getpart: provide dummy function to build conversion enabled
• conversions: fix several compiler warnings
• openssl: add missing includes
• schannel: Support partial send for when data is too large
• socks: fix incorrect port number in SOCKS4 error message
• curl: fix integer overflow in timeout options
• travis: on mac, don't install openssl or libidn
• cookies: reject oversized cookies instead of truncating
• cookies: use lock when using CURLINFO_COOKIELIST
• curl: check fseek() return code and bail on error
• examples/post-callback: use long for CURLOPT_POSTFIELDSIZE
• openssl: only verify RSA private key if supported
• tests: make the imap server not verify user+password
• imap: quote atoms properly when escaping characters
• tests: fix a compiler warning in test 643
• file_range: avoid integer overflow when figuring out byte range
• curl.h: include <sys/select.h> on cygwin too
• reuse_conn: don't copy flags that are known to be equal
• http: fix adding custom empty headers to repeated requests
• docs: clarify the use of environment variables for proxy
• docs: link CURLOPT_CONNECTTIMEOUT and CURLOPT_CONNECTTIMEOUT_MS
• connect: fix race condition with happy eyeballs timeout
• cookie: fix memory leak if path was set twice in header
• vtls: compare and clone ssl configs properly
• proxy: read the "no_proxy" variable only if necessary

Further