re-add zstd support, enabled in the "big" builds [ci skip]

Strictly experimental, might be gone in a next commit.

```
curl 7.84.0 (x86_64-w64-mingw32) libcurl/7.84.0 BoringSSL/7528f03c (Schannel) zlib/1.2.12 brotli/1.0.9 zstd/1.5.2 libidn2/2.3.3 libpsl/0.21.1 (+libidn2/2.3.3) libssh2/1.10.0 nghttp2/1.48.0 ngtcp2/0.6.0 nghttp3/0.5.0 libgsasl/1.10.0
Release-Date: 2022-06-27
Protocols: dict file ftp ftps gopher gophers http https imap imaps ldap ldaps mqtt pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp
Features: alt-svc AsynchDNS brotli gsasl HSTS HTTP2 HTTP3 HTTPS-proxy IDN IPv6 Kerberos Largefile libz MultiSSL NTLM PSL SPNEGO SSL SSPI threadsafe UnixSockets zstd
```

README.md

@@ -79,8 +79,8 @@ Libs: -lcurl -lz -lcrypt32 -lwldap32 -lnghttp2 -lssh2 -lgsasl -lbcrypt -lssl -lc
 ```
 "big":
 Protocols: dict file ftp ftps gopher gophers http https imap imaps ldap ldaps mqtt pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp
-Features: alt-svc AsynchDNS brotli gsasl HSTS HTTP2 HTTP3 HTTPS-proxy IDN IPv6 Kerberos Largefile libz MultiSSL NTLM PSL SPNEGO SSL SSPI threadsafe         UnixSockets
-Libs: -lcurl -lz -lcrypt32 -lwldap32 -lnghttp2 -lssh2 -lgsasl          -lssl -lcrypto -lidn2 -lbrotlidec -lbrotlicommon -lnghttp3 -lngtcp2 -lpsl -liconv -lunistring
+Features: alt-svc AsynchDNS brotli gsasl HSTS HTTP2 HTTP3 HTTPS-proxy IDN IPv6 Kerberos Largefile libz MultiSSL NTLM PSL SPNEGO SSL SSPI threadsafe         UnixSockets zstd
+Libs: -lcurl -lz -lcrypt32 -lwldap32 -lnghttp2 -lssh2 -lgsasl          -lssl -lcrypto -lidn2 -lbrotlidec -lbrotlicommon -lnghttp3 -lngtcp2 -lpsl -liconv -lunistring -lzstd
 
 "boringssl":
 Protocols: dict file ftp ftps gopher gophers http https imap imaps ldap ldaps mqtt pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp

_build.sh

@@ -79,6 +79,7 @@ set -o xtrace -o errexit -o nounset; [ -n "${BASH:-}${ZSH_NAME:-}" ] && set -o p
 # Supported build tools:
 #
 #   zlib          cmake
+#   zstd          cmake
 #   brotli        cmake
 #   libunistring  autotools
 #   libiconv      autotools
@@ -687,6 +688,7 @@ build_single_target() {
   } >> "${_UNIMFT}"
 
   bld zlib                 "${ZLIB_VER_}"
+  bld zstd                 "${ZSTD_VER_}"
   bld brotli             "${BROTLI_VER_}"
   bld libunistring "${LIBUNISTRING_VER_}"
   bld libiconv         "${LIBICONV_VER_}"

_dl.sh

@@ -115,6 +115,14 @@ cat <<EOF
     "sig": ".asc",
     "keys": "5ED46A6721D365587791E2AA783FCD8E58BCAFBA"
   },
+  {
+    "name": "zstd",
+    "url": "https://github.com/facebook/zstd/releases/download/v{ver}/zstd-{ver}.tar.gz",
+    "sig": ".sig",
+    "sha": ".sha256",
+    "redir": "redir",
+    "keys": "4EF4AC63455FC9F4545D9B7DEF8FE99528B52FFD"
+  },
   {
     "name": "pefile",
     "url": "https://github.com/erocarrera/pefile/releases/download/v{ver}/pefile-{ver}.tar.gz",
@@ -533,6 +541,9 @@ if [ "${_BRANCH#*pico*}" = "${_BRANCH}" ] && \
 fi
 
 if [ "${_BRANCH#*big*}" != "${_BRANCH}" ]; then
+  live_dl zstd "${ZSTD_VER_}"
+  live_xt zstd "${ZSTD_HASH}"
+
   live_dl libunistring "${LIBUNISTRING_VER_}"
   live_xt libunistring "${LIBUNISTRING_HASH}"
   live_dl libiconv "${LIBICONV_VER_}"

_versions.sh

@@ -34,6 +34,8 @@ export LIBRESSL_VER_='3.5.3'
 export LIBRESSL_HASH=3ab5e5eaef69ce20c6b170ee64d785b42235f48f2e62b095fca5d7b6672b8b28
 export ZLIB_VER_='1.2.12'
 export ZLIB_HASH=7db46b8d7726232a621befaab4a1c870f00a90805511c0e0090441dac57def18
+export ZSTD_VER_='1.5.2'
+export ZSTD_HASH=7c42d56fac126929a6a85dbc73ff1db2411d04f104fae9bdea51305663a83fd0
 export LLVM_MINGW_LINUX_VER_='20220323'
 export LLVM_MINGW_LINUX_HASH=6d69ab28a3a9a2b7159178ff11cae8545fd44c9343573900fcf60434539695d8
 export LLVM_MINGW_MAC_VER_="${LLVM_MINGW_LINUX_VER_}"

curl-autotools.sh

@@ -150,8 +150,13 @@ fi
     else
       options="${options} --without-brotli"
     fi
-
-    options="${options} --without-zstd"
+    if [ -d ../zstd ]; then
+      options="${options} --with-zstd=${_TOP}/zstd/${_PP}"
+      LDFLAGS="${LDFLAGS} -L${_TOP}/zstd/${_PP}/lib"
+      LIBS="${LIBS} -lzstd"
+    else
+      options="${options} --without-zstd"
+    fi
 
     options="${options} --with-schannel"
     CPPFLAGS="${CPPFLAGS} -DHAS_ALPN"

curl-cmake.sh

@@ -135,6 +135,13 @@ _VER="$1"
     else
       options="${options} -DCURL_BROTLI=OFF"
     fi
+    if [ -d ../zstd ]; then
+      options="${options} -DCURL_ZSTD=ON"
+      options="${options} -DZstd_LIBRARY=${_TOP}/zstd/${_PP}/lib/libzstd.a"
+      options="${options} -DZstd_INCLUDE_DIR=${_TOP}/zstd/${_PP}/include"
+    else
+      options="${options} -DCURL_ZSTD=OFF"
+    fi
 
     if [ -d ../libressl ]; then
       options="${options} -DCURL_USE_OPENSSL=ON"

curl-m32.sh

@@ -135,6 +135,11 @@ _VER="$1"
     export BROTLI_PATH="../../brotli/${_PP}"
     export BROTLI_LIBS='-Wl,-Bstatic -lbrotlidec -lbrotlicommon -Wl,-Bdynamic'
   fi
+  if [ -d ../zstd ]; then
+    options="${options}-zstd"
+    export ZSTD_PATH="../../zstd/${_PP}"
+    export ZSTD_LIBS='-Wl,-Bstatic -lzstd -Wl,-Bdynamic'
+  fi
 
   export OPENSSL_LIBS=''
   if [ -d ../libressl ]; then

zstd.sh

@@ -0,0 +1,66 @@
+#!/bin/sh
+
+# Copyright 2017-present Viktor Szakats. See LICENSE.md
+
+# shellcheck disable=SC3040
+set -o xtrace -o errexit -o nounset; [ -n "${BASH:-}${ZSH_NAME:-}" ] && set -o pipefail
+
+export _NAM _VER _OUT _BAS _DST
+
+_NAM="$(basename "$0" | cut -f 1 -d '.')"
+_VER="$1"
+
+(
+  cd "${_NAM}" || exit 0
+
+  rm -r -f "${_PKGDIR}" "${_BLDDIR}"
+
+  _CFLAGS="${_CFLAGS_GLOBAL} ${_CPPFLAGS_GLOBAL}"
+
+  # shellcheck disable=SC2086
+  cmake build/cmake -B "${_BLDDIR}" ${_CMAKE_GLOBAL} ${_CMAKE_CXX_GLOBAL} \
+    '-DZSTD_BUILD_CONTRIB=OFF' \
+    '-DZSTD_BUILD_TESTS=OFF' \
+    '-DZSTD_LEGACY_SUPPORT=OFF' \
+    '-DZSTD_BUILD_PROGRAMS=OFF' \
+    '-DZSTD_PROGRAMS_LINK_SHARED=OFF' \
+    '-DZSTD_BUILD_SHARED=OFF' \
+    '-DZSTD_BUILD_STATIC=ON' \
+    '-DZSTD_MULTITHREAD_SUPPORT=OFF' \
+    "-DCMAKE_C_FLAGS=-Wno-unused-command-line-argument ${_CFLAGS} ${_LDFLAGS_GLOBAL} ${_LIBS_GLOBAL}" \
+    "-DCMAKE_CXX_FLAGS=-Wno-unused-command-line-argument ${_CFLAGS} ${_LDFLAGS_GLOBAL} ${_LIBS_GLOBAL} ${_CXXFLAGS_GLOBAL} ${_LDFLAGS_CXX_GLOBAL}"
+
+  make --directory="${_BLDDIR}" --jobs="${_JOBS}" install "DESTDIR=$(pwd)/${_PKGDIR}"
+
+  _pkg="${_PP}"  # DESTDIR= + _PREFIX
+
+  # Delete .pc files
+  rm -r -f "${_pkg}"/lib/pkgconfig
+
+  # Make steps for determinism
+
+  readonly _ref='CHANGELOG'
+
+  "${_STRIP}" --enable-deterministic-archives --strip-debug "${_pkg}"/lib/*.a
+
+  touch -c -r "${_ref}" "${_pkg}"/include/*.h
+  touch -c -r "${_ref}" "${_pkg}"/lib/*.a
+
+  # Create package
+
+  _OUT="${_NAM}-${_VER}${_REVSUFFIX}${_PKGSUFFIX}"
+  _BAS="${_NAM}-${_VER}${_PKGSUFFIX}"
+  _DST="$(mktemp -d)/${_BAS}"
+
+  mkdir -p "${_DST}"
+  mkdir -p "${_DST}/include"
+  mkdir -p "${_DST}/lib"
+
+  cp -f -p "${_pkg}"/include/*.h "${_DST}/include/"
+  cp -f -p "${_pkg}"/lib/*.a     "${_DST}/lib/"
+  cp -f -p CHANGELOG             "${_DST}/CHANGELOG.txt"
+  cp -f -p README.md             "${_DST}/"
+  cp -f -p LICENSE               "${_DST}/LICENSE.txt"
+
+  ../_pkg.sh "$(pwd)/${_ref}"
+)