content_encoding: add zstd decoding support

include zstd curl patch for Makefile.m32 from vszakats
and include Add CMake support for zstd from Peter Wu

Helped-by: Viktor Szakats
Helped-by: Peter Wu
Closes #5453

1 files changed, 91 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index ffce699a4..ed1b5fcec 100755
--- a/configure.ac
+++ b/configure.ac
@@ -1116,6 +1116,93 @@ if test X"$OPT_BROTLI" != Xno; then
 fi
 
 dnl **********************************************************************
+dnl Check for libzstd
+dnl **********************************************************************
+
+dnl Default to compiler & linker defaults for libzstd
+OPT_ZSTD=off
+AC_ARG_WITH(zstd,dnl
+AC_HELP_STRING([--with-zstd=PATH],[Where to look for libzstd, PATH points to the libzstd installation; when possible, set the PKG_CONFIG_PATH environment variable instead of using this option])
+AC_HELP_STRING([--without-zstd], [disable libzstd]),
+  OPT_ZSTD=$withval)
+
+if test X"$OPT_ZSTD" != Xno; then
+  dnl backup the pre-zstd variables
+  CLEANLDFLAGS="$LDFLAGS"
+  CLEANCPPFLAGS="$CPPFLAGS"
+  CLEANLIBS="$LIBS"
+
+  case "$OPT_ZSTD" in
+  yes)
+    dnl --with-zstd (without path) used
+    CURL_CHECK_PKGCONFIG(libzstd)
+
+    if test "$PKGCONFIG" != "no" ; then
+      LIB_ZSTD=`$PKGCONFIG --libs-only-l libzstd`
+      LD_ZSTD=`$PKGCONFIG --libs-only-L libzstd`
+      CPP_ZSTD=`$PKGCONFIG --cflags-only-I libzstd`
+      version=`$PKGCONFIG --modversion libzstd`
+      DIR_ZSTD=`echo $LD_ZSTD | $SED -e 's/-L//'`
+    fi
+
+    ;;
+  off)
+    dnl no --with-zstd option given, just check default places
+    ;;
+  *)
+    dnl use the given --with-zstd spot
+    PREFIX_ZSTD=$OPT_ZSTD
+    ;;
+  esac
+
+  dnl if given with a prefix, we set -L and -I based on that
+  if test -n "$PREFIX_ZSTD"; then
+    LIB_ZSTD="-lzstd"
+    LD_ZSTD=-L${PREFIX_ZSTD}/lib$libsuff
+    CPP_ZSTD=-I${PREFIX_ZSTD}/include
+    DIR_ZSTD=${PREFIX_ZSTD}/lib$libsuff
+  fi
+
+  LDFLAGS="$LDFLAGS $LD_ZSTD"
+  CPPFLAGS="$CPPFLAGS $CPP_ZSTD"
+  LIBS="$LIB_ZSTD $LIBS"
+
+  AC_CHECK_LIB(zstd, ZSTD_createDStream)
+
+  AC_CHECK_HEADERS(zstd.h,
+    curl_zstd_msg="enabled (libzstd)"
+    HAVE_ZSTD=1
+    AC_DEFINE(HAVE_ZSTD, 1, [if libzstd is in use])
+    AC_SUBST(HAVE_ZSTD, [1])
+  )
+
+  if test X"$OPT_ZSTD" != Xoff &&
+     test "$HAVE_ZSTD" != "1"; then
+    AC_MSG_ERROR([libzstd was not found where specified!])
+  fi
+
+  if test "$HAVE_ZSTD" = "1"; then
+    if test -n "$DIR_ZSTD"; then
+       dnl when the zstd shared lib were found in a path that the run-time
+       dnl linker doesn't search through, we need to add it to
+       dnl CURL_LIBRARY_PATH to prevent further configure tests to fail due to
+       dnl this
+
+       if test "x$cross_compiling" != "xyes"; then
+         CURL_LIBRARY_PATH="$CURL_LIBRARY_PATH:$DIR_ZSTD"
+         export CURL_LIBRARY_PATH
+         AC_MSG_NOTICE([Added $DIR_ZSTD to CURL_LIBRARY_PATH])
+       fi
+    fi
+  else
+    dnl no zstd, revert back to clean variables
+    LDFLAGS=$CLEANLDFLAGS
+    CPPFLAGS=$CLEANCPPFLAGS
+    LIBS=$CLEANLIBS
+  fi
+fi
+
+dnl **********************************************************************
 dnl Check for LDAP
 dnl **********************************************************************
 
@@ -4825,6 +4912,9 @@ fi
 if test "x$HAVE_BROTLI" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES brotli"
 fi
+if test "x$HAVE_ZSTD" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES zstd"
+fi
 if test "x$USE_ARES" = "x1" -o "x$USE_THREADS_POSIX" = "x1" \
                             -o "x$USE_THREADS_WIN32" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES AsynchDNS"
@@ -5067,6 +5157,7 @@ AC_MSG_NOTICE([Configured to build curl/libcurl:
   SSH:              ${curl_ssh_msg}
   zlib:             ${curl_zlib_msg}
   brotli:           ${curl_brotli_msg}
+  zstd:             ${curl_zstd_msg}
   GSS-API:          ${curl_gss_msg}
   TLS-SRP:          ${curl_tls_srp_msg}
   resolver:         ${curl_res_msg}