smtp: use the upload buffer size for scratch buffer malloc
[platform/upstream/curl.git] / configure.ac
old mode 100644 (file)
new mode 100755 (executable)
index 5c387cc..c261f49
@@ -5,11 +5,11 @@
 #                            | (__| |_| |  _ <| |___
 #                             \___|\___/|_| \_\_____|
 #
-# Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
 #
 # This software is licensed as described in the file COPYING, which
 # you should have received as part of this distribution. The terms
-# are also available at http://curl.haxx.se/docs/copyright.html.
+# are also available at https://curl.haxx.se/docs/copyright.html.
 #
 # You may opt to use, copy, modify, merge, publish, distribute and/or sell
 # copies of the Software, and permit persons to whom the Software is
@@ -24,21 +24,22 @@ dnl Process this file with autoconf to produce a configure script.
 AC_PREREQ(2.57)
 
 dnl We don't know the version number "statically" so we use a dash here
-AC_INIT([curl], [-], [a suitable curl mailing list: http://curl.haxx.se/mail/])
+AC_INIT([curl], [-], [a suitable curl mailing list: https://curl.haxx.se/mail/])
 
 XC_OVR_ZZ50
 XC_OVR_ZZ60
 CURL_OVERRIDE_AUTOCONF
 
 dnl configure script copyright
-AC_COPYRIGHT([Copyright (c) 1998 - 2014 Daniel Stenberg, <daniel@haxx.se>
+AC_COPYRIGHT([Copyright (c) 1998 - 2017 Daniel Stenberg, <daniel@haxx.se>
 This configure script may be copied, distributed and modified under the
 terms of the curl license; see COPYING for more details])
 
 AC_CONFIG_SRCDIR([lib/urldata.h])
-AC_CONFIG_HEADERS(lib/curl_config.h include/curl/curlbuild.h)
+AC_CONFIG_HEADERS(lib/curl_config.h)
 AC_CONFIG_MACRO_DIR([m4])
 AM_MAINTAINER_MODE
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 
 CURL_CHECK_OPTION_DEBUG
 CURL_CHECK_OPTION_OPTIMIZE
@@ -47,6 +48,7 @@ CURL_CHECK_OPTION_WERROR
 CURL_CHECK_OPTION_CURLDEBUG
 CURL_CHECK_OPTION_SYMBOL_HIDING
 CURL_CHECK_OPTION_ARES
+CURL_CHECK_OPTION_RT
 
 XC_CHECK_PATH_SEPARATOR
 
@@ -118,14 +120,16 @@ AC_SUBST([AR])
 
 AC_SUBST(libext)
 
-dnl Remove non-configure distributed curlbuild.h
-if test -f ${srcdir}/include/curl/curlbuild.h; then
-  rm -f ${srcdir}/include/curl/curlbuild.h
-fi
-
 dnl figure out the libcurl version
-CURLVERSION=`$SED -ne 's/^#define LIBCURL_VERSION "\(.*\)"/\1/p' ${srcdir}/include/curl/curlver.h`
+CURLVERSION=`$SED -ne 's/^#define LIBCURL_VERSION "\(.*\)".*/\1/p' ${srcdir}/include/curl/curlver.h`
 XC_CHECK_PROG_CC
+
+dnl Check if gcc is being used before adding AX_CODE_COVERAGE
+AS_IF([ test "$GCC" = "yes" ], [AX_CODE_COVERAGE],
+  # not using GCC so pass a test below - CODE_COVERAGE_ENABLED_TRUE is not zero length
+  CODE_COVERAGE_ENABLED_TRUE='#'
+)
+
 XC_AUTOMAKE
 AC_MSG_CHECKING([curl version])
 AC_MSG_RESULT($CURLVERSION)
@@ -134,12 +138,12 @@ AC_SUBST(CURLVERSION)
 
 dnl
 dnl we extract the numerical version for curl-config only
-VERSIONNUM=`$SED -ne 's/^#define LIBCURL_VERSION_NUM 0x\(.*\)/\1/p' ${srcdir}/include/curl/curlver.h`
+VERSIONNUM=`$SED -ne 's/^#define LIBCURL_VERSION_NUM 0x\([0-9A-Fa-f]*\).*/\1/p' ${srcdir}/include/curl/curlver.h`
 AC_SUBST(VERSIONNUM)
 
 dnl Solaris pkgadd support definitions
 PKGADD_PKG="HAXXcurl"
-PKGADD_NAME="cURL - a client that groks URLs"
+PKGADD_NAME="curl - a client that groks URLs"
 PKGADD_VENDOR="curl.haxx.se"
 AC_SUBST(PKGADD_PKG)
 AC_SUBST(PKGADD_NAME)
@@ -147,15 +151,16 @@ AC_SUBST(PKGADD_VENDOR)
 
 dnl
 dnl initialize all the info variables
-    curl_ssl_msg="no      (--with-{ssl,gnutls,nss,polarssl,cyassl,axtls,winssl,darwinssl} )"
+    curl_ssl_msg="no      (--with-{ssl,gnutls,nss,polarssl,mbedtls,cyassl,axtls,winssl,darwinssl} )"
     curl_ssh_msg="no      (--with-libssh2)"
    curl_zlib_msg="no      (--with-zlib)"
+ curl_brotli_msg="no      (--with-brotli)"
     curl_gss_msg="no      (--with-gssapi)"
- curl_spnego_msg="no      (--with-spnego)"
 curl_tls_srp_msg="no      (--enable-tls-srp)"
     curl_res_msg="default (--enable-ares / --enable-threaded-resolver)"
    curl_ipv6_msg="no      (--enable-ipv6)"
-    curl_idn_msg="no      (--with-{libidn,winidn})"
+curl_unix_sockets_msg="no      (--enable-unix-sockets)"
+    curl_idn_msg="no      (--with-{libidn2,winidn})"
  curl_manual_msg="no      (--enable-manual)"
 curl_libcurl_msg="enabled (--disable-libcurl-option)"
 curl_verbose_msg="enabled (--disable-verbose)"
@@ -165,8 +170,9 @@ curl_verbose_msg="enabled (--disable-verbose)"
    curl_rtsp_msg="no      (--enable-rtsp)"
    curl_rtmp_msg="no      (--with-librtmp)"
   curl_mtlnk_msg="no      (--with-libmetalink)"
+    curl_psl_msg="no      (--with-libpsl)"
 
-    init_ssl_msg=${curl_ssl_msg}
+    ssl_backends=
 
 dnl
 dnl Save some initial values the user might have provided
@@ -184,9 +190,6 @@ AC_DEFINE_UNQUOTED(OS, "${host}", [cpu-machine-OS])
 
 dnl Checks for programs.
 
-dnl Our curl_off_t internal and external configure settings
-CURL_CONFIGURE_CURL_OFF_T
-
 dnl This defines _ALL_SOURCE for AIX
 CURL_CHECK_AIX_ALL_SOURCE
 
@@ -336,7 +339,7 @@ dnl **********************************************************************
 
 CURL_CHECK_HEADER_WINDOWS
 CURL_CHECK_NATIVE_WINDOWS
-case X-"$ac_cv_native_windows" in
+case X-"$curl_cv_native_windows" in
   X-yes)
     CURL_CHECK_HEADER_WINSOCK
     CURL_CHECK_HEADER_WINSOCK2
@@ -345,15 +348,18 @@ case X-"$ac_cv_native_windows" in
     CURL_CHECK_HEADER_WINBER
     ;;
   *)
-    ac_cv_header_winsock_h="no"
-    ac_cv_header_winsock2_h="no"
-    ac_cv_header_ws2tcpip_h="no"
-    ac_cv_header_winldap_h="no"
-    ac_cv_header_winber_h="no"
+    curl_cv_header_winsock_h="no"
+    curl_cv_header_winsock2_h="no"
+    curl_cv_header_ws2tcpip_h="no"
+    curl_cv_header_winldap_h="no"
+    curl_cv_header_winber_h="no"
     ;;
 esac
 CURL_CHECK_WIN32_LARGEFILE
 
+CURL_MAC_CFLAGS
+CURL_SUPPORTS_BUILTIN_AVAILABLE
+
 dnl ************************************************************
 dnl switch off particular protocols
 dnl
@@ -365,6 +371,7 @@ AC_HELP_STRING([--disable-http],[Disable HTTP support]),
   no)
        AC_MSG_RESULT(no)
        AC_DEFINE(CURL_DISABLE_HTTP, 1, [to disable HTTP])
+       disable_http="yes"
        AC_MSG_WARN([disable HTTP disables FTP over proxy and RTSP])
        AC_SUBST(CURL_DISABLE_HTTP, [1])
        AC_DEFINE(CURL_DISABLE_RTSP, 1, [to disable RTSP])
@@ -575,6 +582,22 @@ AC_HELP_STRING([--disable-imap],[Disable IMAP support]),
 )
 
 
+AC_MSG_CHECKING([whether to support smb])
+AC_ARG_ENABLE(smb,
+AC_HELP_STRING([--enable-smb],[Enable SMB/CIFS support])
+AC_HELP_STRING([--disable-smb],[Disable SMB/CIFS support]),
+[ case "$enableval" in
+  no)
+       AC_MSG_RESULT(no)
+       AC_DEFINE(CURL_DISABLE_SMB, 1, [to disable SMB/CIFS])
+       AC_SUBST(CURL_DISABLE_SMB, [1])
+       ;;
+  *)   AC_MSG_RESULT(yes)
+       ;;
+  esac ],
+       AC_MSG_RESULT(yes)
+)
+
 AC_MSG_CHECKING([whether to support smtp])
 AC_ARG_ENABLE(smtp,
 AC_HELP_STRING([--enable-smtp],[Enable SMTP support])
@@ -723,8 +746,8 @@ fi
 if test "$HAVE_GETHOSTBYNAME" != "1"
 then
   dnl This is for winsock systems
-  if test "$ac_cv_header_windows_h" = "yes"; then
-    if test "$ac_cv_header_winsock_h" = "yes"; then
+  if test "$curl_cv_header_windows_h" = "yes"; then
+    if test "$curl_cv_header_winsock_h" = "yes"; then
       case $host in
         *-*-mingw32ce*)
           winsock_LIB="-lwinsock"
@@ -734,7 +757,7 @@ then
           ;;
       esac
     fi
-    if test "$ac_cv_header_winsock2_h" = "yes"; then
+    if test "$curl_cv_header_winsock2_h" = "yes"; then
       winsock_LIB="-lws2_32"
     fi
     if test ! -z "$winsock_LIB"; then
@@ -832,17 +855,6 @@ if test "$HAVE_GETHOSTBYNAME" != "1"; then
   AC_MSG_ERROR([couldn't find libraries for gethostbyname()])
 fi
 
-dnl resolve lib?
-AC_CHECK_FUNC(strcasecmp, , [ AC_CHECK_LIB(resolve, strcasecmp) ])
-
-if test "$ac_cv_lib_resolve_strcasecmp" = "$ac_cv_func_strcasecmp"; then
-  AC_CHECK_LIB(resolve, strcasecmp,
-              [LIBS="-lresolve $LIBS"],
-               ,
-               -lnsl)
-fi
-ac_cv_func_strcasecmp="no"
-
 CURL_CHECK_LIBS_CONNECT
 
 CURL_NETWORK_LIBS=$LIBS
@@ -884,16 +896,28 @@ else
   fi
 
   if test -z "$OPT_ZLIB" ; then
-    dnl check for the lib first without setting any new path, since many
-    dnl people have it in the default path
+    CURL_CHECK_PKGCONFIG(zlib)
+
+    if test "$PKGCONFIG" != "no" ; then
+      LIBS="`$PKGCONFIG --libs-only-l zlib` $LIBS"
+      LDFLAGS="$LDFLAGS `$PKGCONFIG --libs-only-L zlib`"
+      CPPFLAGS="$CPPFLAGS `$PKGCONFIG --cflags-only-I zlib`"
+      OPT_ZLIB=""
+      HAVE_LIBZ="1"
+    fi
+
+    if test -z "$HAVE_LIBZ"; then
 
-    AC_CHECK_LIB(z, inflateEnd,
+      dnl Check for the lib without setting any new path, since many
+      dnl people have it in the default path
+
+      AC_CHECK_LIB(z, inflateEnd,
                    dnl libz found, set the variable
                    [HAVE_LIBZ="1"
                     LIBS="-lz $LIBS"],
                    dnl if no lib found, try /usr/local
                    [OPT_ZLIB="/usr/local"])
-
+    fi
   fi
 
   dnl Add a nonempty path to the compiler flags
@@ -959,6 +983,94 @@ AM_CONDITIONAL(HAVE_LIBZ, test x"$AMFIXLIB" = x1)
 AC_SUBST(ZLIB_LIBS)
 
 dnl **********************************************************************
+dnl Check for the presence of BROTLI decoder libraries and headers
+dnl **********************************************************************
+
+dnl Brotli project home page: https://github.com/google/brotli
+
+dnl Default to compiler & linker defaults for BROTLI files & libraries.
+OPT_BROTLI=off
+AC_ARG_WITH(brotli,dnl
+AC_HELP_STRING([--with-brotli=PATH],[Where to look for brotli, PATH points to the BROTLI installation; when possible, set the PKG_CONFIG_PATH environment variable instead of using this option])
+AC_HELP_STRING([--without-brotli], [disable BROTLI]),
+  OPT_BROTLI=$withval)
+
+if test X"$OPT_BROTLI" != Xno; then
+  dnl backup the pre-brotli variables
+  CLEANLDFLAGS="$LDFLAGS"
+  CLEANCPPFLAGS="$CPPFLAGS"
+  CLEANLIBS="$LIBS"
+
+  case "$OPT_BROTLI" in
+  yes)
+    dnl --with-brotli (without path) used
+    CURL_CHECK_PKGCONFIG(libbrotlidec)
+
+    if test "$PKGCONFIG" != "no" ; then
+      LIB_BROTLI=`$PKGCONFIG --libs-only-l libbrotlidec`
+      LD_BROTLI=`$PKGCONFIG --libs-only-L libbrotlidec`
+      CPP_BROTLI=`$PKGCONFIG --cflags-only-I libbrotlidec`
+      version=`$PKGCONFIG --modversion libbrotlidec`
+      DIR_BROTLI=`echo $LD_BROTLI | $SED -e 's/-L//'`
+    fi
+
+    ;;
+  off)
+    dnl no --with-brotli option given, just check default places
+    ;;
+  *)
+    dnl use the given --with-brotli spot
+    PREFIX_BROTLI=$OPT_BROTLI
+    ;;
+  esac
+
+  dnl if given with a prefix, we set -L and -I based on that
+  if test -n "$PREFIX_BROTLI"; then
+    LIB_BROTLI="-lbrotlidec"
+    LD_BROTLI=-L${PREFIX_BROTLI}/lib$libsuff
+    CPP_BROTLI=-I${PREFIX_BROTLI}/include
+    DIR_BROTLI=${PREFIX_BROTLI}/lib$libsuff
+  fi
+
+  LDFLAGS="$LDFLAGS $LD_BROTLI"
+  CPPFLAGS="$CPPFLAGS $CPP_BROTLI"
+  LIBS="$LIB_BROTLI $LIBS"
+
+  AC_CHECK_LIB(brotlidec, BrotliDecoderDecompress)
+
+  AC_CHECK_HEADERS(brotli/decode.h,
+    curl_brotli_msg="enabled (libbrotlidec)"
+    HAVE_BROTLI=1
+    AC_DEFINE(HAVE_BROTLI, 1, [if BROTLI is in use])
+    AC_SUBST(HAVE_BROTLI, [1])
+  )
+
+  if test X"$OPT_BROTLI" != Xoff &&
+     test "$HAVE_BROTLI" != "1"; then
+    AC_MSG_ERROR([BROTLI libs and/or directories were not found where specified!])
+  fi
+
+  if test "$HAVE_BROTLI" = "1"; then
+    if test -n "$DIR_BROTLI"; then
+       dnl when the brotli shared libs were found in a path that the run-time
+       dnl linker doesn't search through, we need to add it to LD_LIBRARY_PATH
+       dnl to prevent further configure tests to fail due to this
+
+       if test "x$cross_compiling" != "xyes"; then
+         LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$DIR_BROTLI"
+         export LD_LIBRARY_PATH
+         AC_MSG_NOTICE([Added $DIR_BROTLI to LD_LIBRARY_PATH])
+       fi
+    fi
+  else
+    dnl no brotli, revert back to clean variables
+    LDFLAGS=$CLEANLDFLAGS
+    CPPFLAGS=$CLEANCPPFLAGS
+    LIBS=$CLEANLIBS
+  fi
+fi
+
+dnl **********************************************************************
 dnl Check for LDAP
 dnl **********************************************************************
 
@@ -980,7 +1092,7 @@ if test x$CURL_DISABLE_LDAP != x1 ; then
   CURL_CHECK_HEADER_LDAP_SSL
 
   if test -z "$LDAPLIBNAME" ; then
-    if test "$ac_cv_native_windows" = "yes"; then
+    if test "$curl_cv_native_windows" = "yes"; then
       dnl Windows uses a single and unique LDAP library name
       LDAPLIBNAME="wldap32"
       LBERLIBNAME="no"
@@ -1030,7 +1142,7 @@ if test x$CURL_DISABLE_LDAP != x1 ; then
 
   if test "$LDAPLIBNAME" = "wldap32"; then
     curl_ldap_msg="enabled (winldap)"
-    AC_DEFINE(CURL_LDAP_WIN, 1, [Use Windows LDAP implementation])
+    AC_DEFINE(USE_WIN32_LDAP, 1, [Use Windows LDAP implementation])
   else
     curl_ldap_msg="enabled (OpenLDAP)"
     if test "x$ac_cv_func_ldap_init_fd" = "xyes"; then
@@ -1048,10 +1160,10 @@ dnl **********************************************************************
 dnl Checks for IPv6
 dnl **********************************************************************
 
-AC_MSG_CHECKING([whether to enable ipv6])
+AC_MSG_CHECKING([whether to enable IPv6])
 AC_ARG_ENABLE(ipv6,
-AC_HELP_STRING([--enable-ipv6],[Enable ipv6 (with ipv4) support])
-AC_HELP_STRING([--disable-ipv6],[Disable ipv6 support]),
+AC_HELP_STRING([--enable-ipv6],[Enable IPv6 (with IPv4) support])
+AC_HELP_STRING([--disable-ipv6],[Disable IPv6 support]),
 [ case "$enableval" in
   no)
        AC_MSG_RESULT(no)
@@ -1064,7 +1176,11 @@ AC_HELP_STRING([--disable-ipv6],[Disable ipv6 support]),
 
   AC_TRY_RUN([ /* is AF_INET6 available? */
 #include <sys/types.h>
+#ifdef HAVE_WINSOCK2_H
+#include <winsock2.h>
+#else
 #include <sys/socket.h>
+#endif
 #include <stdlib.h> /* for exit() */
 main()
 {
@@ -1078,8 +1194,8 @@ main()
   ipv6=yes,
   AC_MSG_RESULT(no)
   ipv6=no,
-  AC_MSG_RESULT(no)
-  ipv6=no
+  AC_MSG_RESULT(yes)
+  ipv6=yes
 ))
 
 if test "$ipv6" = "yes"; then
@@ -1091,7 +1207,15 @@ if test "$ipv6" = yes; then
   AC_MSG_CHECKING([if struct sockaddr_in6 has sin6_scope_id member])
   AC_TRY_COMPILE([
 #include <sys/types.h>
-#include <netinet/in.h>] ,
+#ifdef HAVE_WINSOCK2_H
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#else
+#include <netinet/in.h>
+#if defined (__TANDEM)
+# include <netinet/in6.h>
+#endif
+#endif] ,
   struct sockaddr_in6 s; s.sin6_scope_id = 0; , have_sin6_scope_id=yes)
   if test "$have_sin6_scope_id" = yes; then
     AC_MSG_RESULT([yes])
@@ -1135,41 +1259,6 @@ no)
 esac
 
 dnl **********************************************************************
-dnl Check for FBopenssl(SPNEGO) libraries
-dnl **********************************************************************
-
-AC_ARG_WITH(spnego,
-  AC_HELP_STRING([--with-spnego=DIR],
-                 [Specify location of SPNEGO library fbopenssl]), [
-  SPNEGO_ROOT="$withval"
-  if test x"$SPNEGO_ROOT" != xno; then
-    want_spnego="yes"
-  fi
-])
-
-AC_MSG_CHECKING([if SPNEGO support is requested])
-if test x"$want_spnego" = xyes; then
-
-  if test X"$SPNEGO_ROOT" = Xyes; then
-     AC_MSG_ERROR([FBOpenSSL libs and/or directories were not found where specified!])
-     AC_MSG_RESULT(no)
-  else
-     if test -z "$SPNEGO_LIB_DIR"; then
-        LDFLAGS="$LDFLAGS -L$SPNEGO_ROOT -lfbopenssl"
-     else
-        LDFLAGS="$LDFLAGS $SPNEGO_LIB_DIR"
-     fi
-
-     AC_MSG_RESULT(yes)
-     AC_DEFINE(HAVE_SPNEGO, 1,
-               [Define this if you have the SPNEGO library fbopenssl])
-     curl_spnego_msg="enabled"
-  fi
-else
-  AC_MSG_RESULT(no)
-fi
-
-dnl **********************************************************************
 dnl Check for GSS-API libraries
 dnl **********************************************************************
 
@@ -1203,14 +1292,18 @@ AC_ARG_WITH(gssapi,
   fi
 ])
 
+: ${KRB5CONFIG:="$GSSAPI_ROOT/bin/krb5-config"}
+
 save_CPPFLAGS="$CPPFLAGS"
 AC_MSG_CHECKING([if GSS-API support is requested])
 if test x"$want_gss" = xyes; then
   AC_MSG_RESULT(yes)
 
   if test -z "$GSSAPI_INCS"; then
-     if test -f "$GSSAPI_ROOT/bin/krb5-config"; then
-        GSSAPI_INCS=`$GSSAPI_ROOT/bin/krb5-config --cflags gssapi`
+     if test -n "$host_alias" -a -f "$GSSAPI_ROOT/bin/$host_alias-krb5-config"; then
+        GSSAPI_INCS=`$GSSAPI_ROOT/bin/$host_alias-krb5-config --cflags gssapi`
+     elif test -f "$KRB5CONFIG"; then
+        GSSAPI_INCS=`$KRB5CONFIG --cflags gssapi`
      elif test "$GSSAPI_ROOT" != "yes"; then
         GSSAPI_INCS="-I$GSSAPI_ROOT/include"
      fi
@@ -1282,7 +1375,7 @@ else
 fi
 if test x"$want_gss" = xyes; then
   AC_DEFINE(HAVE_GSSAPI, 1, [if you have GSS-API libraries])
-
+  HAVE_GSSAPI=1
   curl_gss_msg="enabled (MIT Kerberos/Heimdal)"
 
   if test -n "$gnu_gss"; then
@@ -1294,23 +1387,33 @@ if test x"$want_gss" = xyes; then
      *-*-darwin*)
         LIBS="-lgssapi_krb5 -lresolv $LIBS"
         ;;
-     *-hp-hpux*)
-        if test "$GSSAPI_ROOT" != "yes"; then
-           LDFLAGS="$LDFLAGS -L$GSSAPI_ROOT/lib$libsuff"
-        fi
-        LIBS="-lgss $LIBS"
-        ;;
      *)
-        if test -f "$GSSAPI_ROOT/bin/krb5-config"; then
+        if test -n "$host_alias" -a -f "$GSSAPI_ROOT/bin/$host_alias-krb5-config"; then
+           dnl krb5-config doesn't have --libs-only-L or similar, put everything
+           dnl into LIBS
+           gss_libs=`$GSSAPI_ROOT/bin/$host_alias-krb5-config --libs gssapi`
+           LIBS="$gss_libs $LIBS"
+        elif test -f "$KRB5CONFIG"; then
            dnl krb5-config doesn't have --libs-only-L or similar, put everything
            dnl into LIBS
-           gss_libs=`$GSSAPI_ROOT/bin/krb5-config --libs gssapi`
+           gss_libs=`$KRB5CONFIG --libs gssapi`
            LIBS="$gss_libs $LIBS"
-        elif test "$GSSAPI_ROOT" != "yes"; then
-           LDFLAGS="$LDFLAGS -L$GSSAPI_ROOT/lib$libsuff"
-           LIBS="-lgssapi $LIBS"
         else
-           LIBS="-lgssapi $LIBS"
+           case $host in
+           *-hp-hpux*)
+              gss_libname="gss"
+              ;;
+           *)
+              gss_libname="gssapi"
+              ;;
+           esac
+
+           if test "$GSSAPI_ROOT" != "yes"; then
+              LDFLAGS="$LDFLAGS -L$GSSAPI_ROOT/lib$libsuff"
+              LIBS="-l$gss_libname $LIBS"
+           else
+              LIBS="-l$gss_libname $LIBS"
+           fi
         fi
         ;;
      esac
@@ -1329,6 +1432,41 @@ else
   CPPFLAGS="$save_CPPFLAGS"
 fi
 
+build_libstubgss=no
+if test x"$want_gss" = "xyes"; then
+  build_libstubgss=yes
+fi
+
+AM_CONDITIONAL(BUILD_STUB_GSS, test "x$build_libstubgss" = "xyes")
+
+dnl -------------------------------------------------------------
+dnl parse --with-default-ssl-backend so it can be validated below
+dnl -------------------------------------------------------------
+
+DEFAULT_SSL_BACKEND=no
+VALID_DEFAULT_SSL_BACKEND=
+AC_ARG_WITH(default-ssl-backend,
+AC_HELP_STRING([--with-default-ssl-backend=NAME],[Use NAME as default SSL backend])
+AC_HELP_STRING([--without-default-ssl-backend],[Use implicit default SSL backend]),
+  [DEFAULT_SSL_BACKEND=$withval])
+case "$DEFAULT_SSL_BACKEND" in
+  no)
+    dnl --without-default-ssl-backend option used
+    ;;
+  default|yes)
+    dnl --with-default-ssl-backend option used without name
+    AC_MSG_ERROR([The name of the default SSL backend is required.])
+    ;;
+  *)
+    dnl --with-default-ssl-backend option used with name
+    AC_SUBST(DEFAULT_SSL_BACKEND)
+    dnl needs to be validated below
+    VALID_DEFAULT_SSL_BACKEND=no
+    ;;
+esac
+
+dnl **********************************************************************
+
 dnl -------------------------------------------------
 dnl check winssl option before other SSL libraries
 dnl -------------------------------------------------
@@ -1340,44 +1478,50 @@ AC_HELP_STRING([--without-winssl], [disable Windows native SSL/TLS]),
   OPT_WINSSL=$withval)
 
 AC_MSG_CHECKING([whether to enable Windows native SSL/TLS (Windows native builds only)])
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_WINSSL" != xno; then
+  ssl_msg=
   if test "x$OPT_WINSSL" != "xno"  &&
-     test "x$ac_cv_native_windows" = "xyes"; then
+     test "x$curl_cv_native_windows" = "xyes"; then
     AC_MSG_RESULT(yes)
     AC_DEFINE(USE_SCHANNEL, 1, [to enable Windows native SSL/TLS support])
     AC_SUBST(USE_SCHANNEL, [1])
-    curl_ssl_msg="enabled (Windows-native)"
+    ssl_msg="Windows-native"
+    test schannel != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
     WINSSL_ENABLED=1
     # --with-winssl implies --enable-sspi
     AC_DEFINE(USE_WINDOWS_SSPI, 1, [to enable SSPI support])
     AC_SUBST(USE_WINDOWS_SSPI, [1])
     curl_sspi_msg="enabled"
+    LIBS="-lcrypt32 $LIBS"
   else
     AC_MSG_RESULT(no)
   fi
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 else
   AC_MSG_RESULT(no)
 fi
 
 OPT_DARWINSSL=no
 AC_ARG_WITH(darwinssl,dnl
-AC_HELP_STRING([--with-darwinssl],[enable iOS/Mac OS X native SSL/TLS])
-AC_HELP_STRING([--without-darwinssl], [disable iOS/Mac OS X native SSL/TLS]),
+AC_HELP_STRING([--with-darwinssl],[enable Apple OS native SSL/TLS])
+AC_HELP_STRING([--without-darwinssl], [disable Apple OS native SSL/TLS]),
   OPT_DARWINSSL=$withval)
 
-AC_MSG_CHECKING([whether to enable iOS/Mac OS X native SSL/TLS])
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+AC_MSG_CHECKING([whether to enable Apple OS native SSL/TLS])
+if test -z "$ssl_backends" -o "x$OPT_DARWINSSL" != xno; then
   if test "x$OPT_DARWINSSL" != "xno" &&
      test -d "/System/Library/Frameworks/Security.framework"; then
     AC_MSG_RESULT(yes)
-    AC_DEFINE(USE_DARWINSSL, 1, [to enable iOS/Mac OS X native SSL/TLS support])
+    AC_DEFINE(USE_DARWINSSL, 1, [to enable Apple OS native SSL/TLS support])
     AC_SUBST(USE_DARWINSSL, [1])
-    curl_ssl_msg="enabled (iOS/Mac OS X-native)"
+    ssl_msg="Apple OS-native"
+    test darwinssl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
     DARWINSSL_ENABLED=1
     LDFLAGS="$LDFLAGS -framework CoreFoundation -framework Security"
   else
     AC_MSG_RESULT(no)
   fi
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 else
   AC_MSG_RESULT(no)
 fi
@@ -1395,12 +1539,33 @@ AC_HELP_STRING([--with-ssl=PATH],[Where to look for OpenSSL, PATH points to the
 AC_HELP_STRING([--without-ssl], [disable OpenSSL]),
   OPT_SSL=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
+if test -z "$ssl_backends" -o "x$OPT_SSL" != xno &&
+   test X"$OPT_SSL" != Xno; then
+  ssl_msg=
+
   dnl backup the pre-ssl variables
   CLEANLDFLAGS="$LDFLAGS"
   CLEANCPPFLAGS="$CPPFLAGS"
   CLEANLIBS="$LIBS"
 
+  dnl This is for Msys/Mingw
+  case $host in
+    *-*-msys* | *-*-mingw*)
+      AC_MSG_CHECKING([for gdi32])
+      my_ac_save_LIBS=$LIBS
+      LIBS="-lgdi32 $LIBS"
+      AC_TRY_LINK([#include <windef.h>
+                   #include <wingdi.h>],
+                   [GdiFlush();],
+                   [ dnl worked!
+                   AC_MSG_RESULT([yes])],
+                   [ dnl failed, restore LIBS
+                   LIBS=$my_ac_save_LIBS
+                   AC_MSG_RESULT(no)]
+                  )
+      ;;
+  esac
+
   case "$OPT_SSL" in
   yes)
     dnl --with-ssl (without path) used
@@ -1458,6 +1623,7 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
       SSL_CPPFLAGS=`CURL_EXPORT_PCDIR([$OPENSSL_PCDIR]) dnl
         $PKGCONFIG --cflags-only-I openssl 2>/dev/null`
 
+      AC_SUBST(SSL_LIBS)
       AC_MSG_NOTICE([pkg-config: SSL_LIBS: "$SSL_LIBS"])
       AC_MSG_NOTICE([pkg-config: SSL_LDFLAGS: "$SSL_LDFLAGS"])
       AC_MSG_NOTICE([pkg-config: SSL_CPPFLAGS: "$SSL_CPPFLAGS"])
@@ -1478,39 +1644,59 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
   CPPFLAGS="$CPPFLAGS $SSL_CPPFLAGS"
   LDFLAGS="$LDFLAGS $SSL_LDFLAGS"
 
-  dnl This is for Msys/Mingw
-  case $host in
-    *-*-msys* | *-*-mingw*)
-      AC_MSG_CHECKING([for gdi32])
-      my_ac_save_LIBS=$LIBS
-      LIBS="-lgdi32 $LIBS"
-      AC_TRY_LINK([#include <windef.h>
-                   #include <wingdi.h>],
-                   [GdiFlush();],
-                   [ dnl worked!
-                   AC_MSG_RESULT([yes])],
-                   [ dnl failed, restore LIBS
-                   LIBS=$my_ac_save_LIBS
-                   AC_MSG_RESULT(no)]
-                  )
-      ;;
-  esac
-
-  AC_CHECK_LIB(crypto, CRYPTO_lock,[
+  AC_CHECK_LIB(crypto, HMAC_Update,[
      HAVECRYPTO="yes"
      LIBS="-lcrypto $LIBS"
      ],[
      LDFLAGS="$CLEANLDFLAGS -L$LIB_OPENSSL"
      CPPFLAGS="$CLEANCPPFLAGS -I$PREFIX_OPENSSL/include/openssl -I$PREFIX_OPENSSL/include"
-     AC_CHECK_LIB(crypto, CRYPTO_add_lock,[
+     AC_CHECK_LIB(crypto, HMAC_Init_ex,[
        HAVECRYPTO="yes"
        LIBS="-lcrypto $LIBS"], [
-       LDFLAGS="$CLEANLDFLAGS"
-       CPPFLAGS="$CLEANCPPFLAGS"
-       LIBS="$CLEANLIBS"
+
+       dnl still no, but what about with -ldl?
+       AC_MSG_CHECKING([OpenSSL linking with -ldl])
+       LIBS="$LIBS -ldl"
+       AC_TRY_LINK(
+       [
+         #include <openssl/err.h>
+       ],
+       [
+         ERR_clear_error();
+       ],
+       [
+         AC_MSG_RESULT(yes)
+         HAVECRYPTO="yes"
+       ],
+       [
+         AC_MSG_RESULT(no)
+         dnl ok, so what about bouth -ldl and -lpthread?
+
+         AC_MSG_CHECKING([OpenSSL linking with -ldl and -lpthread])
+         LIBS="$LIBS -lpthread"
+         AC_TRY_LINK(
+         [
+           #include <openssl/err.h>
+         ],
+         [
+           ERR_clear_error();
+         ],
+         [
+           AC_MSG_RESULT(yes)
+           HAVECRYPTO="yes"
+         ],
+         [
+           AC_MSG_RESULT(no)
+           LDFLAGS="$CLEANLDFLAGS"
+           CPPFLAGS="$CLEANCPPFLAGS"
+           LIBS="$CLEANLIBS"
+
+         ])
+
        ])
-    ])
 
+     ])
+  ])
 
   if test X"$HAVECRYPTO" = X"yes"; then
     dnl This is only reasonable to do if crypto actually is there: check for
@@ -1534,10 +1720,11 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
 
     else
 
-      dnl Have the libraries--check for SSLeay/OpenSSL headers
+      dnl Have the libraries--check for OpenSSL headers
       AC_CHECK_HEADERS(openssl/x509.h openssl/rsa.h openssl/crypto.h \
                        openssl/pem.h openssl/ssl.h openssl/err.h,
-        curl_ssl_msg="enabled (OpenSSL)"
+        ssl_msg="OpenSSL"
+       test openssl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
         OPENSSL_ENABLED=1
         AC_DEFINE(USE_OPENSSL, 1, [if OpenSSL is in use]))
 
@@ -1551,24 +1738,15 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
            test $ac_cv_header_crypto_h = yes &&
            test $ac_cv_header_ssl_h = yes; then
           dnl three matches
-          curl_ssl_msg="enabled (OpenSSL)"
+          ssl_msg="OpenSSL"
           OPENSSL_ENABLED=1
         fi
       fi
     fi
 
-    if test X"$OPENSSL_ENABLED" = X"1"; then
-       AC_DEFINE(USE_SSLEAY, 1, [if SSL is enabled])
-
-       dnl is there a pkcs12.h header present?
-       AC_CHECK_HEADERS(openssl/pkcs12.h)
-    else
+    if test X"$OPENSSL_ENABLED" != X"1"; then
        LIBS="$CLEANLIBS"
     fi
-    dnl USE_SSLEAY is the historical name for what configure calls
-    dnl OPENSSL_ENABLED; the names should really be unified
-    USE_SSLEAY="$OPENSSL_ENABLED"
-    AC_SUBST(USE_SSLEAY)
 
     if test X"$OPT_SSL" != Xoff &&
        test "$OPENSSL_ENABLED" != "1"; then
@@ -1585,40 +1763,46 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
                 AC_CHECK_FUNCS( ENGINE_load_builtin_engines )
               ])
 
-    dnl these can only exist if openssl exists
-    dnl yassl doesn't have SSL_get_shutdown
+    dnl These can only exist if OpenSSL exists
+    dnl Older versions of Cyassl (some time before 2.9.4) don't have
+    dnl SSL_get_shutdown (but this check won't actually detect it there
+    dnl as it's a macro that needs the header files be included)
 
-    AC_CHECK_FUNCS( RAND_status \
-                    RAND_screen \
-                    RAND_egd \
+    AC_CHECK_FUNCS( RAND_egd \
                     ENGINE_cleanup \
-                    CRYPTO_cleanup_all_ex_data \
                     SSL_get_shutdown \
-                    SSLv2_client_method \
-                    SSL_CTX_set_next_proto_select_cb \
-                    SSL_CTX_set_alpn_protos \
-                    SSL_CTX_set_alpn_select_cb )
+                    SSLv2_client_method )
 
-    dnl Make an attempt to detect if this is actually yassl's headers and
-    dnl OpenSSL emulation layer. We still leave everything else believing
-    dnl and acting like OpenSSL.
+    AC_MSG_CHECKING([for BoringSSL])
+    AC_COMPILE_IFELSE([
+        AC_LANG_PROGRAM([[
+                #include <openssl/base.h>
+                ]],[[
+                #ifndef OPENSSL_IS_BORINGSSL
+                #error not boringssl
+                #endif
+       ]])
+    ],[
+        AC_MSG_RESULT([yes])
+        AC_DEFINE_UNQUOTED(HAVE_BORINGSSL, 1,
+                           [Define to 1 if using BoringSSL.])
+        ssl_msg="BoringSSL"
+    ],[
+        AC_MSG_RESULT([no])
+    ])
 
-    AC_MSG_CHECKING([for yaSSL using OpenSSL compatibility mode])
+    AC_MSG_CHECKING([for libressl])
     AC_COMPILE_IFELSE([
       AC_LANG_PROGRAM([[
-#include <openssl/ssl.h>
+#include <openssl/opensslv.h>
       ]],[[
-#if defined(YASSL_VERSION) && defined(OPENSSL_VERSION_NUMBER)
-        int dummy = SSL_ERROR_NONE;
-#else
-        Not the yaSSL OpenSSL compatibility header.
-#endif
+        int dummy = LIBRESSL_VERSION_NUMBER;
       ]])
     ],[
       AC_MSG_RESULT([yes])
-      AC_DEFINE_UNQUOTED(USE_YASSLEMUL, 1,
-        [Define to 1 if using yaSSL in OpenSSL compatibility mode.])
-      curl_ssl_msg="enabled (OpenSSL emulation by yaSSL)"
+      AC_DEFINE_UNQUOTED(HAVE_LIBRESSL, 1,
+        [Define to 1 if using libressl.])
+      ssl_msg="libressl"
     ],[
       AC_MSG_RESULT([no])
     ])
@@ -1638,6 +1822,7 @@ if test "$curl_ssl_msg" = "$init_ssl_msg" && test X"$OPT_SSL" != Xno; then
     CURL_CHECK_OPENSSL_API
   fi
 
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 fi
 
 dnl **********************************************************************
@@ -1682,8 +1867,8 @@ dnl ---
 if test "$OPENSSL_ENABLED" = "1"; then
   AC_CHECK_LIB(crypto, SRP_Calc_client_key,
    [
-     AC_DEFINE(HAVE_SSLEAY_SRP, 1, [if you have the function SRP_Calc_client_key])
-     AC_SUBST(HAVE_SSLEAY_SRP, [1])
+     AC_DEFINE(HAVE_OPENSSL_SRP, 1, [if you have the function SRP_Calc_client_key])
+     AC_SUBST(HAVE_OPENSSL_SRP, [1])
    ])
 fi
 
@@ -1699,7 +1884,8 @@ AC_HELP_STRING([--with-gnutls=PATH],[where to look for GnuTLS, PATH points to th
 AC_HELP_STRING([--without-gnutls], [disable GnuTLS detection]),
   OPT_GNUTLS=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_GNUTLS" != xno; then
+  ssl_msg=
 
   if test X"$OPT_GNUTLS" != Xno; then
 
@@ -1773,7 +1959,8 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
        AC_SUBST(USE_GNUTLS, [1])
        GNUTLS_ENABLED=1
        USE_GNUTLS="yes"
-       curl_ssl_msg="enabled (GnuTLS)"
+       ssl_msg="GnuTLS"
+       test gnutls != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
        ],
        [
          LIBS="$CLEANLIBS"
@@ -1788,18 +1975,20 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
           dnl linker doesn't search through, we need to add it to
           dnl LD_LIBRARY_PATH to prevent further configure tests to fail
           dnl due to this
-          if test "x$cross_compiling" != "xyes"; then 
+          if test "x$cross_compiling" != "xyes"; then
             LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$gtlslib"
             export LD_LIBRARY_PATH
             AC_MSG_NOTICE([Added $gtlslib to LD_LIBRARY_PATH])
           fi
         fi
+        AC_CHECK_FUNCS([gnutls_certificate_set_x509_key_file2 gnutls_alpn_set_protocols gnutls_ocsp_req_init])
       fi
 
     fi
 
   fi dnl GNUTLS not disabled
 
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 fi
 
 dnl ---
@@ -1857,7 +2046,8 @@ AC_HELP_STRING([--with-polarssl=PATH],[where to look for PolarSSL, PATH points t
 AC_HELP_STRING([--without-polarssl], [disable PolarSSL detection]),
   OPT_POLARSSL=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_POLARSSL" != xno; then
+  ssl_msg=
 
   if test X"$OPT_POLARSSL" != Xno; then
 
@@ -1875,7 +2065,8 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
          AC_SUBST(USE_POLARSSL, [1])
          POLARSSL_ENABLED=1
          USE_POLARSSL="yes"
-         curl_ssl_msg="enabled (PolarSSL)"
+         ssl_msg="PolarSSL"
+        test polarssl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
         ])
     fi
 
@@ -1901,7 +2092,8 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
        AC_SUBST(USE_POLARSSL, [1])
        POLARSSL_ENABLED=1
        USE_POLARSSL="yes"
-       curl_ssl_msg="enabled (PolarSSL)"
+       ssl_msg="PolarSSL"
+       test polarssl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
        ],
        [
          CPPFLAGS=$_cppflags
@@ -1929,6 +2121,98 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
 
   fi dnl PolarSSL not disabled
 
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
+fi
+
+dnl ----------------------------------------------------
+dnl check for mbedTLS
+dnl ----------------------------------------------------
+
+OPT_MBEDTLS=no
+
+_cppflags=$CPPFLAGS
+_ldflags=$LDFLAGS
+AC_ARG_WITH(mbedtls,dnl
+AC_HELP_STRING([--with-mbedtls=PATH],[where to look for mbedTLS, PATH points to the installation root])
+AC_HELP_STRING([--without-mbedtls], [disable mbedTLS detection]),
+  OPT_MBEDTLS=$withval)
+
+if test -z "$ssl_backends" -o "x$OPT_MBEDTLS" != xno; then
+  ssl_msg=
+
+  if test X"$OPT_MBEDTLS" != Xno; then
+
+    if test "$OPT_MBEDTLS" = "yes"; then
+      OPT_MBEDTLS=""
+    fi
+
+    if test -z "$OPT_MBEDTLS" ; then
+      dnl check for lib first without setting any new path
+
+      AC_CHECK_LIB(mbedtls, mbedtls_havege_init,
+      dnl libmbedtls found, set the variable
+       [
+         AC_DEFINE(USE_MBEDTLS, 1, [if mbedTLS is enabled])
+         AC_SUBST(USE_MBEDTLS, [1])
+         MBEDTLS_ENABLED=1
+         USE_MBEDTLS="yes"
+         ssl_msg="mbedTLS"
+        test mbedtls != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
+        ], [], -lmbedx509 -lmbedcrypto)
+    fi
+
+    addld=""
+    addlib=""
+    addcflags=""
+    mbedtlslib=""
+
+    if test "x$USE_MBEDTLS" != "xyes"; then
+      dnl add the path and test again
+      addld=-L$OPT_MBEDTLS/lib$libsuff
+      addcflags=-I$OPT_MBEDTLS/include
+      mbedtlslib=$OPT_MBEDTLS/lib$libsuff
+
+      LDFLAGS="$LDFLAGS $addld"
+      if test "$addcflags" != "-I/usr/include"; then
+         CPPFLAGS="$CPPFLAGS $addcflags"
+      fi
+
+      AC_CHECK_LIB(mbedtls, mbedtls_ssl_init,
+       [
+       AC_DEFINE(USE_MBEDTLS, 1, [if mbedTLS is enabled])
+       AC_SUBST(USE_MBEDTLS, [1])
+       MBEDTLS_ENABLED=1
+       USE_MBEDTLS="yes"
+       ssl_msg="mbedTLS"
+       test mbedtls != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
+       ],
+       [
+         CPPFLAGS=$_cppflags
+         LDFLAGS=$_ldflags
+       ], -lmbedx509 -lmbedcrypto)
+    fi
+
+    if test "x$USE_MBEDTLS" = "xyes"; then
+      AC_MSG_NOTICE([detected mbedTLS])
+
+      LIBS="-lmbedtls -lmbedx509 -lmbedcrypto $LIBS"
+
+      if test -n "$mbedtlslib"; then
+        dnl when shared libs were found in a path that the run-time
+        dnl linker doesn't search through, we need to add it to
+        dnl LD_LIBRARY_PATH to prevent further configure tests to fail
+        dnl due to this
+        if test "x$cross_compiling" != "xyes"; then
+          LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$mbedtlslib"
+          export LD_LIBRARY_PATH
+          AC_MSG_NOTICE([Added $mbedtlslib to LD_LIBRARY_PATH])
+        fi
+      fi
+    fi
+
+  fi dnl mbedTLS not disabled
+
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 fi
 
 dnl ----------------------------------------------------
@@ -1945,7 +2229,8 @@ AC_HELP_STRING([--with-cyassl=PATH],[where to look for CyaSSL, PATH points to th
 AC_HELP_STRING([--without-cyassl], [disable CyaSSL detection]),
   OPT_CYASSL=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_CYASSL" != xno; then
+  ssl_msg=
 
   if test X"$OPT_CYASSL" != Xno; then
 
@@ -1953,6 +2238,10 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
       OPT_CYASSL=""
     fi
 
+    dnl This should be reworked to use pkg-config instead
+
+    cyassllibname=cyassl
+
     if test -z "$OPT_CYASSL" ; then
       dnl check for lib in system default first
 
@@ -1963,7 +2252,8 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
          AC_SUBST(USE_CYASSL, [1])
          CYASSL_ENABLED=1
          USE_CYASSL="yes"
-         curl_ssl_msg="enabled (CyaSSL)"
+         ssl_msg="CyaSSL"
+        test cyassl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
         ])
     fi
 
@@ -1989,31 +2279,97 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
        AC_SUBST(USE_CYASSL, [1])
        CYASSL_ENABLED=1
        USE_CYASSL="yes"
-       curl_ssl_msg="enabled (CyaSSL)"
+       ssl_msg="CyaSSL"
+       test cyassl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
        ],
        [
          CPPFLAGS=$_cppflags
          LDFLAGS=$_ldflags
+         cyassllib=""
        ])
     fi
 
-    if test "x$USE_CYASSL" = "xyes"; then
-      AC_MSG_NOTICE([detected CyaSSL])
+    addld=""
+    addlib=""
+    addcflags=""
 
-      dnl cyassl/ctaocrypt/types.h needs SIZEOF_LONG_LONG defined!
-      AC_CHECK_SIZEOF(long long)
+    if test "x$USE_CYASSL" != "xyes"; then
+      dnl libcyassl renamed to libwolfssl as of 3.4.0
+      addld=-L$OPT_CYASSL/lib$libsuff
+      addcflags=-I$OPT_CYASSL/include
+      cyassllib=$OPT_CYASSL/lib$libsuff
 
-      dnl Versions since at least 2.9.4 renamed error.h to error-ssl.h
-      AC_CHECK_HEADERS(cyassl/error-ssl.h)
+      LDFLAGS="$LDFLAGS $addld"
+      if test "$addcflags" != "-I/usr/include"; then
+         CPPFLAGS="$CPPFLAGS $addcflags"
+      fi
 
-      LIBS="-lcyassl -lm $LIBS"
+      cyassllibname=wolfssl
+      my_ac_save_LIBS="$LIBS"
+      LIBS="-l$cyassllibname -lm $LIBS"
 
-      if test -n "$cyassllib"; then
-        dnl when shared libs were found in a path that the run-time
-        dnl linker doesn't search through, we need to add it to
-        dnl LD_LIBRARY_PATH to prevent further configure tests to fail
-        dnl due to this
-        if test "x$cross_compiling" != "xyes"; then
+      AC_MSG_CHECKING([for CyaSSL_Init in -lwolfssl])
+      AC_LINK_IFELSE([
+       AC_LANG_PROGRAM([[
+/* These aren't needed for detection and confuse WolfSSL.
+   They are set up properly later if it is detected.  */
+#undef SIZEOF_LONG
+#undef SIZEOF_LONG_LONG
+#include <cyassl/ssl.h>
+       ]],[[
+         return CyaSSL_Init();
+       ]])
+      ],[
+         AC_MSG_RESULT(yes)
+         AC_DEFINE(USE_CYASSL, 1, [if CyaSSL/WolfSSL is enabled])
+         AC_SUBST(USE_CYASSL, [1])
+         CYASSL_ENABLED=1
+         USE_CYASSL="yes"
+         ssl_msg="WolfSSL"
+        test cyassl != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
+       ],
+       [
+         AC_MSG_RESULT(no)
+         CPPFLAGS=$_cppflags
+         LDFLAGS=$_ldflags
+         cyassllib=""
+       ])
+      LIBS="$my_ac_save_LIBS"
+    fi
+
+    if test "x$USE_CYASSL" = "xyes"; then
+      AC_MSG_NOTICE([detected $cyassllibname])
+
+      dnl cyassl/ctaocrypt/types.h needs SIZEOF_LONG_LONG defined!
+      AC_CHECK_SIZEOF(long long)
+
+      dnl Versions since at least 2.6.0 may have options.h
+      AC_CHECK_HEADERS(cyassl/options.h)
+
+      dnl Versions since at least 2.9.4 renamed error.h to error-ssl.h
+      AC_CHECK_HEADERS(cyassl/error-ssl.h)
+
+      LIBS="-l$cyassllibname -lm $LIBS"
+
+      if test "x$cyassllibname" = "xwolfssl"; then
+        dnl Recent WolfSSL versions build without SSLv3 by default
+        dnl WolfSSL needs configure --enable-opensslextra to have *get_peer*
+        AC_CHECK_FUNCS(wolfSSLv3_client_method \
+                       wolfSSL_CTX_UseSupportedCurve \
+                       wolfSSL_get_peer_certificate \
+                       wolfSSL_UseALPN)
+      else
+        dnl Cyassl needs configure --enable-opensslextra to have *get_peer*
+        AC_CHECK_FUNCS(CyaSSL_CTX_UseSupportedCurve \
+                       CyaSSL_get_peer_certificate)
+      fi
+
+      if test -n "$cyassllib"; then
+        dnl when shared libs were found in a path that the run-time
+        dnl linker doesn't search through, we need to add it to
+        dnl LD_LIBRARY_PATH to prevent further configure tests to fail
+        dnl due to this
+        if test "x$cross_compiling" != "xyes"; then
           LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$cyassllib"
           export LD_LIBRARY_PATH
           AC_MSG_NOTICE([Added $cyassllib to LD_LIBRARY_PATH])
@@ -2024,6 +2380,7 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
 
   fi dnl CyaSSL not disabled
 
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 fi
 
 dnl ----------------------------------------------------
@@ -2038,7 +2395,8 @@ AC_HELP_STRING([--with-nss=PATH],[where to look for NSS, PATH points to the inst
 AC_HELP_STRING([--without-nss], [disable NSS detection]),
   OPT_NSS=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_NSS" != xno; then
+  ssl_msg=
 
   if test X"$OPT_NSS" != Xno; then
 
@@ -2073,56 +2431,87 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
         fi
       fi
     else
-        # Without pkg-config, we'll kludge in some defaults
-        addlib="-L$OPT_NSS/lib -lssl3 -lsmime3 -lnss3 -lplds4 -lplc4 -lnspr4 -lpthread -ldl"
-        addcflags="-I$OPT_NSS/include"
-        version="unknown"
-        nssprefix=$OPT_NSS
+      NSS_PCDIR="$OPT_NSS/lib/pkgconfig"
+      if test -f "$NSS_PCDIR/nss.pc"; then
+        CURL_CHECK_PKGCONFIG(nss, [$NSS_PCDIR])
+        if test "$PKGCONFIG" != "no" ; then
+          addld=`CURL_EXPORT_PCDIR([$NSS_PCDIR]) $PKGCONFIG --libs-only-L nss`
+          addlib=`CURL_EXPORT_PCDIR([$NSS_PCDIR]) $PKGCONFIG --libs-only-l nss`
+          addcflags=`CURL_EXPORT_PCDIR([$NSS_PCDIR]) $PKGCONFIG --cflags nss`
+          version=`CURL_EXPORT_PCDIR([$NSS_PCDIR]) $PKGCONFIG --modversion nss`
+          nssprefix=`CURL_EXPORT_PCDIR([$NSS_PCDIR]) $PKGCONFIG --variable=prefix nss`
+        fi
+      fi
     fi
 
-    if test -n "$addlib"; then
+    if test -z "$addlib"; then
+      # Without pkg-config, we'll kludge in some defaults
+      AC_MSG_WARN([Using hard-wired libraries and compilation flags for NSS.])
+      addld="-L$OPT_NSS/lib"
+      addlib="-lssl3 -lsmime3 -lnss3 -lplds4 -lplc4 -lnspr4"
+      addcflags="-I$OPT_NSS/include"
+      version="unknown"
+      nssprefix=$OPT_NSS
+    fi
 
-      CLEANLIBS="$LIBS"
-      CLEANCPPFLAGS="$CPPFLAGS"
+    CLEANLDFLAGS="$LDFLAGS"
+    CLEANLIBS="$LIBS"
+    CLEANCPPFLAGS="$CPPFLAGS"
 
-      LIBS="$addlib $LIBS"
-      if test "$addcflags" != "-I/usr/include"; then
-         CPPFLAGS="$CPPFLAGS $addcflags"
-      fi
+    LDFLAGS="$addld $LDFLAGS"
+    LIBS="$addlib $LIBS"
+    if test "$addcflags" != "-I/usr/include"; then
+       CPPFLAGS="$CPPFLAGS $addcflags"
+    fi
 
-      dnl The function SSL_VersionRangeSet() is needed to enable TLS > 1.0
-      AC_CHECK_LIB(nss3, SSL_VersionRangeSet,
-       [
-       AC_DEFINE(USE_NSS, 1, [if NSS is enabled])
-       AC_SUBST(USE_NSS, [1])
-       USE_NSS="yes"
-       NSS_ENABLED=1
-       curl_ssl_msg="enabled (NSS)"
-       ],
-       [
-         LIBS="$CLEANLIBS"
-         CPPFLAGS="$CLEANCPPFLAGS"
-       ])
+    dnl The function SSL_VersionRangeSet() is needed to enable TLS > 1.0
+    AC_CHECK_LIB(nss3, SSL_VersionRangeSet,
+     [
+     AC_DEFINE(USE_NSS, 1, [if NSS is enabled])
+     AC_SUBST(USE_NSS, [1])
+     USE_NSS="yes"
+     NSS_ENABLED=1
+     ssl_msg="NSS"
+     test nss != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
+     ],
+     [
+       LDFLAGS="$CLEANLDFLAGS"
+       LIBS="$CLEANLIBS"
+       CPPFLAGS="$CLEANCPPFLAGS"
+     ])
 
-      if test "x$USE_NSS" = "xyes"; then
-        AC_MSG_NOTICE([detected NSS version $version])
+    if test "x$USE_NSS" = "xyes"; then
+      AC_MSG_NOTICE([detected NSS version $version])
 
-        dnl when shared libs were found in a path that the run-time
-        dnl linker doesn't search through, we need to add it to
-        dnl LD_LIBRARY_PATH to prevent further configure tests to fail
-        dnl due to this
-        if test "x$cross_compiling" != "xyes"; then
-          LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$nssprefix/lib$libsuff"
-          export LD_LIBRARY_PATH
-          AC_MSG_NOTICE([Added $nssprefix/lib$libsuff to LD_LIBRARY_PATH])
-        fi
+      dnl PK11_CreateManagedGenericObject() was introduced in NSS 3.34 because
+      dnl PK11_DestroyGenericObject() does not release resources allocated by
+      dnl PK11_CreateGenericObject() early enough.
+      AC_CHECK_FUNC(PK11_CreateManagedGenericObject,
+        [
+          AC_DEFINE(HAVE_PK11_CREATEMANAGEDGENERICOBJECT, 1,
+                    [if you have the PK11_CreateManagedGenericObject function])
+        ])
+
+      dnl needed when linking the curl tool without USE_EXPLICIT_LIB_DEPS
+      NSS_LIBS=$addlib
+      AC_SUBST([NSS_LIBS])
+
+      dnl when shared libs were found in a path that the run-time
+      dnl linker doesn't search through, we need to add it to
+      dnl LD_LIBRARY_PATH to prevent further configure tests to fail
+      dnl due to this
+      if test "x$cross_compiling" != "xyes"; then
+        LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$nssprefix/lib$libsuff"
+        export LD_LIBRARY_PATH
+        AC_MSG_NOTICE([Added $nssprefix/lib$libsuff to LD_LIBRARY_PATH])
       fi
 
-    fi
+    fi dnl NSS found
 
   fi dnl NSS not disabled
 
-fi dnl curl_ssl_msg = init_ssl_msg
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
+fi
 
 OPT_AXTLS=off
 
@@ -2131,7 +2520,8 @@ AC_HELP_STRING([--with-axtls=PATH],[Where to look for axTLS, PATH points to the
 AC_HELP_STRING([--without-axtls], [disable axTLS]),
   OPT_AXTLS=$withval)
 
-if test "$curl_ssl_msg" = "$init_ssl_msg"; then
+if test -z "$ssl_backends" -o "x$OPT_AXTLS" != xno; then
+  ssl_msg=
   if test X"$OPT_AXTLS" != Xno; then
     dnl backup the pre-axtls variables
     CLEANLDFLAGS="$LDFLAGS"
@@ -2165,7 +2555,8 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
       AC_SUBST(USE_AXTLS, [1])
       AXTLS_ENABLED=1
       USE_AXTLS="yes"
-      curl_ssl_msg="enabled (axTLS)"
+      ssl_msg="axTLS"
+      test axtls != "$DEFAULT_SSL_BACKEND" || VALID_DEFAULT_SSL_BACKEND=yes
 
       if test "x$cross_compiling" != "xyes"; then
         LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$LIB_AXTLS"
@@ -2178,15 +2569,46 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
       LIBS="$CLEANLIBS"
     ])
   fi
+  test -z "$ssl_msg" || ssl_backends="${ssl_backends:+$ssl_backends, }$ssl_msg"
 fi
 
-if test "x$OPENSSL_ENABLED$GNUTLS_ENABLED$NSS_ENABLED$POLARSSL_ENABLED$AXTLS_ENABLED$CYASSL_ENABLED$WINSSL_ENABLED$DARWINSSL_ENABLED" = "x"; then
+case "x$OPENSSL_ENABLED$GNUTLS_ENABLED$NSS_ENABLED$POLARSSL_ENABLED$MBEDTLS_ENABLED$AXTLS_ENABLED$CYASSL_ENABLED$WINSSL_ENABLED$DARWINSSL_ENABLED" in
+x)
   AC_MSG_WARN([SSL disabled, you will not be able to use HTTPS, FTPS, NTLM and more.])
   AC_MSG_WARN([Use --with-ssl, --with-gnutls, --with-polarssl, --with-cyassl, --with-nss, --with-axtls, --with-winssl, or --with-darwinssl to address this.])
-else
-  # SSL is enabled, genericly
+  ;;
+x1)
+  # one SSL backend is enabled
+  AC_SUBST(SSL_ENABLED)
+  SSL_ENABLED="1"
+  AC_MSG_NOTICE([built with one SSL backend])
+  ;;
+*)
+  # more than one SSL backend is enabled
   AC_SUBST(SSL_ENABLED)
   SSL_ENABLED="1"
+  AC_SUBST(CURL_WITH_MULTI_SSL)
+  CURL_WITH_MULTI_SSL="1"
+  AC_DEFINE(CURL_WITH_MULTI_SSL, 1, [built with multiple SSL backends])
+  AC_MSG_NOTICE([built with multiple SSL backends])
+  ;;
+esac
+
+if test -n "$ssl_backends"; then
+  curl_ssl_msg="enabled ($ssl_backends)"
+fi
+
+if test no = "$VALID_DEFAULT_SSL_BACKEND"
+then
+  if test -n "$SSL_ENABLED"
+  then
+    AC_MSG_ERROR([Default SSL backend $DEFAULT_SSL_BACKEND not enabled!])
+  else
+    AC_MSG_ERROR([Default SSL backend requires SSL!])
+  fi
+elif test yes = "$VALID_DEFAULT_SSL_BACKEND"
+then
+  AC_DEFINE_UNQUOTED([CURL_DEFAULT_SSL_BACKEND], ["$DEFAULT_SSL_BACKEND"], [Default SSL backend])
 fi
 
 dnl **********************************************************************
@@ -2196,6 +2618,27 @@ dnl **********************************************************************
 CURL_CHECK_CA_BUNDLE
 
 dnl **********************************************************************
+dnl Check for libpsl
+dnl **********************************************************************
+
+AC_ARG_WITH(libpsl,
+           AS_HELP_STRING([--without-libpsl],
+           [disable support for libpsl cookie checking]),
+           with_libpsl=$withval,
+           with_libpsl=yes)
+if test $with_libpsl != "no"; then
+  AC_SEARCH_LIBS(psl_builtin, psl,
+    [curl_psl_msg="yes";
+     AC_DEFINE([USE_LIBPSL], [1], [PSL support enabled])
+     ],
+    [curl_psl_msg="no      (libpsl not found)";
+     AC_MSG_WARN([libpsl was not found])
+     ]
+  )
+fi
+AM_CONDITIONAL([USE_LIBPSL], [test "$curl_psl_msg" = "yes"])
+
+dnl **********************************************************************
 dnl Check for libmetalink
 dnl **********************************************************************
 
@@ -2246,8 +2689,8 @@ if test X"$OPT_LIBMETALINK" != Xno; then
     clean_CPPFLAGS="$CPPFLAGS"
     clean_LDFLAGS="$LDFLAGS"
     clean_LIBS="$LIBS"
-    CPPFLAGS="$addcflags $clean_CPPFLAGS"
-    LDFLAGS="$addld $clean_LDFLAGS"
+    CPPFLAGS="$clean_CPPFLAGS $addcflags"
+    LDFLAGS="$clean_LDFLAGS $addld"
     LIBS="$addlib $clean_LIBS"
     AC_MSG_CHECKING([if libmetalink is recent enough])
     AC_LINK_IFELSE([
@@ -2291,8 +2734,15 @@ dnl Default to compiler & linker defaults for LIBSSH2 files & libraries.
 OPT_LIBSSH2=off
 AC_ARG_WITH(libssh2,dnl
 AC_HELP_STRING([--with-libssh2=PATH],[Where to look for libssh2, PATH points to the LIBSSH2 installation; when possible, set the PKG_CONFIG_PATH environment variable instead of using this option])
-AC_HELP_STRING([--without-libssh2], [disable LIBSSH2]),
-  OPT_LIBSSH2=$withval)
+AC_HELP_STRING([--with-libssh2], [enable LIBSSH2]),
+  OPT_LIBSSH2=$withval, OPT_LIBSSH2=no)
+
+
+OPT_LIBSSH=off
+AC_ARG_WITH(libssh,dnl
+AC_HELP_STRING([--with-libssh=PATH],[Where to look for libssh, PATH points to the LIBSSH installation; when possible, set the PKG_CONFIG_PATH environment variable instead of using this option])
+AC_HELP_STRING([--with-libssh], [enable LIBSSH]),
+  OPT_LIBSSH=$withval, OPT_LIBSSH=no)
 
 if test X"$OPT_LIBSSH2" != Xno; then
   dnl backup the pre-libssh2 variables
@@ -2355,12 +2805,6 @@ if test X"$OPT_LIBSSH2" != Xno; then
        dnl linker doesn't search through, we need to add it to LD_LIBRARY_PATH
        dnl to prevent further configure tests to fail due to this
 
-       dnl libssh2_version is a post 1.0 addition
-       dnl libssh2_init and libssh2_exit were added in 1.2.5
-       dnl libssh2_scp_send64 was added in 1.2.6
-       dnl libssh2_session_handshake was added in 1.2.8
-       AC_CHECK_FUNCS( libssh2_version libssh2_init libssh2_exit \
-                       libssh2_scp_send64 libssh2_session_handshake)
        if test "x$cross_compiling" != "xyes"; then
          LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$DIR_SSH2"
          export LD_LIBRARY_PATH
@@ -2373,6 +2817,79 @@ if test X"$OPT_LIBSSH2" != Xno; then
     CPPFLAGS=$CLEANCPPFLAGS
     LIBS=$CLEANLIBS
   fi
+elif test X"$OPT_LIBSSH" != Xno; then
+  dnl backup the pre-libssh variables
+  CLEANLDFLAGS="$LDFLAGS"
+  CLEANCPPFLAGS="$CPPFLAGS"
+  CLEANLIBS="$LIBS"
+
+  case "$OPT_LIBSSH" in
+  yes)
+    dnl --with-libssh (without path) used
+    CURL_CHECK_PKGCONFIG(libssh)
+
+    if test "$PKGCONFIG" != "no" ; then
+      LIB_SSH=`$PKGCONFIG --libs-only-l libssh`
+      LD_SSH=`$PKGCONFIG --libs-only-L libssh`
+      CPP_SSH=`$PKGCONFIG --cflags-only-I libssh`
+      version=`$PKGCONFIG --modversion libssh`
+      DIR_SSH=`echo $LD_SSH | $SED -e 's/-L//'`
+    fi
+
+    ;;
+  off)
+    dnl no --with-libssh option given, just check default places
+    ;;
+  *)
+    dnl use the given --with-libssh spot
+    PREFIX_SSH=$OPT_LIBSSH
+    ;;
+  esac
+
+  dnl if given with a prefix, we set -L and -I based on that
+  if test -n "$PREFIX_SSH"; then
+    LIB_SSH="-lssh"
+    LD_SSH=-L${PREFIX_SSH}/lib$libsuff
+    CPP_SSH=-I${PREFIX_SSH}/include
+    DIR_SSH=${PREFIX_SSH}/lib$libsuff
+  fi
+
+  LDFLAGS="$LDFLAGS $LD_SSH"
+  CPPFLAGS="$CPPFLAGS $CPP_SSH"
+  LIBS="$LIB_SSH $LIBS"
+
+  AC_CHECK_LIB(ssh, ssh_new)
+
+  AC_CHECK_HEADERS(libssh/libssh.h,
+    curl_ssh_msg="enabled (libSSH)"
+    LIBSSH_ENABLED=1
+    AC_DEFINE(USE_LIBSSH, 1, [if libSSH is in use])
+    AC_SUBST(USE_LIBSSH, [1])
+  )
+
+  if test X"$OPT_LIBSSH" != Xoff &&
+     test "$LIBSSH_ENABLED" != "1"; then
+    AC_MSG_ERROR([libSSH libs and/or directories were not found where specified!])
+  fi
+
+  if test "$LIBSSH_ENABLED" = "1"; then
+    if test -n "$DIR_SSH"; then
+       dnl when the libssh shared libs were found in a path that the run-time
+       dnl linker doesn't search through, we need to add it to LD_LIBRARY_PATH
+       dnl to prevent further configure tests to fail due to this
+
+       if test "x$cross_compiling" != "xyes"; then
+         LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$DIR_SSH"
+         export LD_LIBRARY_PATH
+         AC_MSG_NOTICE([Added $DIR_SSH to LD_LIBRARY_PATH])
+       fi
+    fi
+  else
+    dnl no libssh, revert back to clean variables
+    LDFLAGS=$CLEANLDFLAGS
+    CPPFLAGS=$CLEANCPPFLAGS
+    LIBS=$CLEANLIBS
+  fi
 fi
 
 dnl **********************************************************************
@@ -2416,6 +2933,7 @@ if test X"$OPT_LIBRTMP" != Xno; then
     ;;
   *)
     dnl use the given --with-librtmp spot
+    LIB_RTMP="-lrtmp"
     PREFIX_RTMP=$OPT_LIBRTMP
     ;;
   esac
@@ -2471,7 +2989,9 @@ AC_HELP_STRING([--disable-versioned-symbols], [Disable versioned symbols in shar
         AC_MSG_WARN([You need an ld version supporting the --version-script option])
     else
         AC_MSG_RESULT(yes)
-        if test "x$OPENSSL_ENABLED" = "x1"; then
+        if test "x$CURL_WITH_MULTI_SSL" = "x1"; then
+          versioned_symbols_flavour="MULTISSL_"
+        elif test "x$OPENSSL_ENABLED" = "x1"; then
           versioned_symbols_flavour="OPENSSL_"
         elif test "x$GNUTLS_ENABLED" = "x1"; then
           versioned_symbols_flavour="GNUTLS_"
@@ -2543,6 +3063,7 @@ if test "$want_winidn" = "yes"; then
   clean_LDFLAGS="$LDFLAGS"
   clean_LIBS="$LIBS"
   WINIDN_LIBS="-lnormaliz"
+  WINIDN_CPPFLAGS="-DWINVER=0x0600"
   #
   if test "$want_winidn_path" != "default"; then
     dnl path has been specified
@@ -2552,13 +3073,17 @@ if test "$want_winidn" = "yes"; then
     WINIDN_DIR="$want_winidn_path/lib$libsuff"
   fi
   #
-  CPPFLAGS="$WINIDN_CPPFLAGS $CPPFLAGS"
-  LDFLAGS="$WINIDN_LDFLAGS $LDFLAGS"
+  CPPFLAGS="$CPPFLAGS $WINIDN_CPPFLAGS"
+  LDFLAGS="$LDFLAGS $WINIDN_LDFLAGS"
   LIBS="$WINIDN_LIBS $LIBS"
   #
   AC_MSG_CHECKING([if IdnToUnicode can be linked])
   AC_LINK_IFELSE([
-    AC_LANG_FUNC_LINK_TRY([IdnToUnicode])
+    AC_LANG_PROGRAM([[
+      #include <windows.h>
+    ]],[[
+      IdnToUnicode(0, NULL, 0, NULL, 0);
+    ]])
   ],[
     AC_MSG_RESULT([yes])
     tst_links_winidn="yes"
@@ -2584,15 +3109,15 @@ dnl **********************************************************************
 dnl Check for the presence of IDN libraries and headers
 dnl **********************************************************************
 
-AC_MSG_CHECKING([whether to build with libidn])
+AC_MSG_CHECKING([whether to build with libidn2])
 OPT_IDN="default"
-AC_ARG_WITH(libidn,
-AC_HELP_STRING([--with-libidn=PATH],[Enable libidn usage])
-AC_HELP_STRING([--without-libidn],[Disable libidn usage]),
+AC_ARG_WITH(libidn2,
+AC_HELP_STRING([--with-libidn2=PATH],[Enable libidn2 usage])
+AC_HELP_STRING([--without-libidn2],[Disable libidn2 usage]),
   [OPT_IDN=$withval])
 case "$OPT_IDN" in
   no)
-    dnl --without-libidn option used
+    dnl --without-libidn2 option used
     want_idn="no"
     AC_MSG_RESULT([no])
     ;;
@@ -2603,13 +3128,13 @@ case "$OPT_IDN" in
     AC_MSG_RESULT([(assumed) yes])
     ;;
   yes)
-    dnl --with-libidn option used without path
+    dnl --with-libidn2 option used without path
     want_idn="yes"
     want_idn_path="default"
     AC_MSG_RESULT([yes])
     ;;
   *)
-    dnl --with-libidn option used with path
+    dnl --with-libidn2 option used with path
     want_idn="yes"
     want_idn_path="$withval"
     AC_MSG_RESULT([yes ($withval)])
@@ -2626,33 +3151,33 @@ if test "$want_idn" = "yes"; then
   if test "$want_idn_path" != "default"; then
     dnl path has been specified
     IDN_PCDIR="$want_idn_path/lib$libsuff/pkgconfig"
-    CURL_CHECK_PKGCONFIG(libidn, [$IDN_PCDIR])
+    CURL_CHECK_PKGCONFIG(libidn2, [$IDN_PCDIR])
     if test "$PKGCONFIG" != "no"; then
       IDN_LIBS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
-        $PKGCONFIG --libs-only-l libidn 2>/dev/null`
+        $PKGCONFIG --libs-only-l libidn2 2>/dev/null`
       IDN_LDFLAGS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
-        $PKGCONFIG --libs-only-L libidn 2>/dev/null`
+        $PKGCONFIG --libs-only-L libidn2 2>/dev/null`
       IDN_CPPFLAGS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
-        $PKGCONFIG --cflags-only-I libidn 2>/dev/null`
+        $PKGCONFIG --cflags-only-I libidn2 2>/dev/null`
       IDN_DIR=`echo $IDN_LDFLAGS | $SED -e 's/-L//'`
     else
       dnl pkg-config not available or provides no info
-      IDN_LIBS="-lidn"
+      IDN_LIBS="-lidn2"
       IDN_LDFLAGS="-L$want_idn_path/lib$libsuff"
       IDN_CPPFLAGS="-I$want_idn_path/include"
       IDN_DIR="$want_idn_path/lib$libsuff"
     fi
   else
     dnl path not specified
-    CURL_CHECK_PKGCONFIG(libidn)
+    CURL_CHECK_PKGCONFIG(libidn2)
     if test "$PKGCONFIG" != "no"; then
-      IDN_LIBS=`$PKGCONFIG --libs-only-l libidn 2>/dev/null`
-      IDN_LDFLAGS=`$PKGCONFIG --libs-only-L libidn 2>/dev/null`
-      IDN_CPPFLAGS=`$PKGCONFIG --cflags-only-I libidn 2>/dev/null`
+      IDN_LIBS=`$PKGCONFIG --libs-only-l libidn2 2>/dev/null`
+      IDN_LDFLAGS=`$PKGCONFIG --libs-only-L libidn2 2>/dev/null`
+      IDN_CPPFLAGS=`$PKGCONFIG --cflags-only-I libidn2 2>/dev/null`
       IDN_DIR=`echo $IDN_LDFLAGS | $SED -e 's/-L//'`
     else
       dnl pkg-config not available or provides no info
-      IDN_LIBS="-lidn"
+      IDN_LIBS="-lidn2"
     fi
   fi
   #
@@ -2668,13 +3193,13 @@ if test "$want_idn" = "yes"; then
     AC_MSG_NOTICE([IDN_DIR: "$IDN_DIR"])
   fi
   #
-  CPPFLAGS="$IDN_CPPFLAGS $CPPFLAGS"
-  LDFLAGS="$IDN_LDFLAGS $LDFLAGS"
+  CPPFLAGS="$CPPFLAGS $IDN_CPPFLAGS"
+  LDFLAGS="$LDFLAGS $IDN_LDFLAGS"
   LIBS="$IDN_LIBS $LIBS"
   #
-  AC_MSG_CHECKING([if idna_to_ascii_4i can be linked])
+  AC_MSG_CHECKING([if idn2_lookup_ul can be linked])
   AC_LINK_IFELSE([
-    AC_LANG_FUNC_LINK_TRY([idna_to_ascii_4i])
+    AC_LANG_FUNC_LINK_TRY([idn2_lookup_ul])
   ],[
     AC_MSG_RESULT([yes])
     tst_links_libidn="yes"
@@ -2682,37 +3207,19 @@ if test "$want_idn" = "yes"; then
     AC_MSG_RESULT([no])
     tst_links_libidn="no"
   ])
-  if test "$tst_links_libidn" = "no"; then
-    AC_MSG_CHECKING([if idna_to_ascii_lz can be linked])
-    AC_LINK_IFELSE([
-      AC_LANG_FUNC_LINK_TRY([idna_to_ascii_lz])
-    ],[
-      AC_MSG_RESULT([yes])
-      tst_links_libidn="yes"
-    ],[
-      AC_MSG_RESULT([no])
-      tst_links_libidn="no"
-    ])
-  fi
   #
+  AC_CHECK_HEADERS( idn2.h )
+
   if test "$tst_links_libidn" = "yes"; then
-    AC_DEFINE(HAVE_LIBIDN, 1, [Define to 1 if you have the `idn' library (-lidn).])
+    AC_DEFINE(HAVE_LIBIDN2, 1, [Define to 1 if you have the `idn2' library (-lidn2).])
     dnl different versions of libidn have different setups of these:
-    AC_CHECK_FUNCS( idn_free idna_strerror tld_strerror )
-    AC_CHECK_HEADERS( idn-free.h tld.h )
-    if test "x$ac_cv_header_tld_h" = "xyes"; then
-      AC_SUBST([IDN_ENABLED], [1])
-      curl_idn_msg="enabled"
-      if test -n "$IDN_DIR" -a "x$cross_compiling" != "xyes"; then
-        LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$IDN_DIR"
-        export LD_LIBRARY_PATH
-        AC_MSG_NOTICE([Added $IDN_DIR to LD_LIBRARY_PATH])
-      fi
-    else
-      AC_MSG_WARN([Libraries for IDN support too old: IDN disabled])
-      CPPFLAGS="$clean_CPPFLAGS"
-      LDFLAGS="$clean_LDFLAGS"
-      LIBS="$clean_LIBS"
+
+    AC_SUBST([IDN_ENABLED], [1])
+    curl_idn_msg="enabled (libidn2)"
+    if test -n "$IDN_DIR" -a "x$cross_compiling" != "xyes"; then
+      LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$IDN_DIR"
+      export LD_LIBRARY_PATH
+      AC_MSG_NOTICE([Added $IDN_DIR to LD_LIBRARY_PATH])
     fi
   else
     AC_MSG_WARN([Cannot find libraries for IDN support: IDN disabled])
@@ -2727,13 +3234,158 @@ dnl Let's hope this split URL remains working:
 dnl http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixprggd/ \
 dnl genprogc/thread_quick_ref.htm
 
+dnl **********************************************************************
+dnl Check for ICU-UC (IDN support)
+dnl **********************************************************************
+
+AC_MSG_CHECKING([whether to build with icu-uc])
+OPT_IDN="default"
+AC_ARG_WITH(icu-uc,
+AC_HELP_STRING([--with-icu-uc=PATH],[Enable icu-uc usage])
+AC_HELP_STRING([--without-icu-uc],[Disable icu-uc usage]),
+  [OPT_IDN=$withval])
+case "$OPT_IDN" in
+  no)
+    dnl --without-icu-uc option used
+    want_idn="no"
+    AC_MSG_RESULT([no])
+    ;;
+  default)
+    dnl configure option not specified
+    want_idn="yes"
+    want_idn_path="default"
+    AC_MSG_RESULT([(assumed) yes])
+    ;;
+  yes)
+    dnl --with-icu-uc option used without path
+    want_idn="yes"
+    want_idn_path="default"
+    AC_MSG_RESULT([yes])
+    ;;
+  *)
+    dnl --with-icu-uc option used with path
+    want_idn="yes"
+    want_idn_path="$withval"
+    AC_MSG_RESULT([yes ($withval)])
+    ;;
+esac
+
+if test "$want_idn" = "yes"; then
+  dnl idn library support has been requested
+  clean_CPPFLAGS="$CPPFLAGS"
+  clean_LDFLAGS="$LDFLAGS"
+  clean_LIBS="$LIBS"
+  PKGCONFIG="no"
+  #
+  if test "$want_idn_path" != "default"; then
+    dnl path has been specified
+    IDN_PCDIR="$want_idn_path/lib$libsuff/pkgconfig"
+    CURL_CHECK_PKGCONFIG(icu-uc, [$IDN_PCDIR])
+    if test "$PKGCONFIG" != "no"; then
+      IDN_LIBS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
+        $PKGCONFIG --libs-only-l icu-uc 2>/dev/null`
+      IDN_LDFLAGS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
+        $PKGCONFIG --libs-only-L icu-uc 2>/dev/null`
+      IDN_CPPFLAGS=`CURL_EXPORT_PCDIR([$IDN_PCDIR]) dnl
+        $PKGCONFIG --cflags-only-I icu-uc 2>/dev/null`
+      IDN_DIR=`echo $IDN_LDFLAGS | $SED -e 's/-L//'`
+    else
+      dnl pkg-config not available or provides no info
+      IDN_LIBS="-licu-uc"
+      IDN_LDFLAGS="-L$want_idn_path/lib$libsuff"
+      IDN_CPPFLAGS="-I$want_idn_path/include"
+      IDN_DIR="$want_idn_path/lib$libsuff"
+    fi
+  else
+    dnl path not specified
+    CURL_CHECK_PKGCONFIG(icu-uc)
+    if test "$PKGCONFIG" != "no"; then
+      IDN_LIBS=`$PKGCONFIG --libs-only-l icu-uc 2>/dev/null`
+      IDN_LDFLAGS=`$PKGCONFIG --libs-only-L icu-uc 2>/dev/null`
+      IDN_CPPFLAGS=`$PKGCONFIG --cflags-only-I icu-uc 2>/dev/null`
+      IDN_DIR=`echo $IDN_LDFLAGS | $SED -e 's/-L//'`
+    else
+      dnl pkg-config not available or provides no info
+      IDN_LIBS="-licu-uc"
+    fi
+  fi
+  #
+  if test "$PKGCONFIG" != "no"; then
+    AC_MSG_NOTICE([pkg-config: IDN_LIBS: "$IDN_LIBS"])
+    AC_MSG_NOTICE([pkg-config: IDN_LDFLAGS: "$IDN_LDFLAGS"])
+    AC_MSG_NOTICE([pkg-config: IDN_CPPFLAGS: "$IDN_CPPFLAGS"])
+    AC_MSG_NOTICE([pkg-config: IDN_DIR: "$IDN_DIR"])
+  else
+    AC_MSG_NOTICE([IDN_LIBS: "$IDN_LIBS"])
+    AC_MSG_NOTICE([IDN_LDFLAGS: "$IDN_LDFLAGS"])
+    AC_MSG_NOTICE([IDN_CPPFLAGS: "$IDN_CPPFLAGS"])
+    AC_MSG_NOTICE([IDN_DIR: "$IDN_DIR"])
+  fi
+  #
+  CPPFLAGS="$IDN_CPPFLAGS $CPPFLAGS"
+  LDFLAGS="$IDN_LDFLAGS $LDFLAGS"
+  LIBS="$IDN_LIBS $LIBS"
+  #
+  AC_MSG_CHECKING([if uidna_nameToASCII_UTF8 can be linked])
+  AC_LINK_IFELSE([
+    AC_LANG_FUNC_LINK_TRY([uidna_nameToASCII_UTF8])
+  ],[
+    AC_MSG_RESULT([yes])
+    tst_links_icu="yes"
+  ],[
+    AC_MSG_RESULT([no])
+    tst_links_icu="no"
+  ])
+  #
+  if test "$tst_links_icu" = "yes"; then
+    AC_DEFINE(USE_ICU_IDNA, 1, [Define to 1 if you have the `icu-uc' library (-licu-uc).])
+    dnl different versions of libidn have different setups of these:
+
+    AC_SUBST([IDN_ENABLED], [1])
+    curl_idn_msg="enabled (icu-uc)"
+    if test -n "$IDN_DIR" -a "x$cross_compiling" != "xyes"; then
+      LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$IDN_DIR"
+      export LD_LIBRARY_PATH
+      AC_MSG_NOTICE([Added $IDN_DIR to LD_LIBRARY_PATH])
+    fi
+  else
+    AC_MSG_WARN([Cannot find libraries for IDN support: IDN disabled])
+    CPPFLAGS="$clean_CPPFLAGS"
+    LDFLAGS="$clean_LDFLAGS"
+    LIBS="$clean_LIBS"
+  fi
+
+fi
+
+dnl Let's hope this split URL remains working:
+dnl http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixprggd/ \
+dnl genprogc/thread_quick_ref.htm
+
+dnl **********************************************************************
+dnl Check for DLP
+dnl **********************************************************************
+
+AC_ARG_ENABLE([dlp],
+    AS_HELP_STRING([--enable-dlp], [Enable DLP usage]))
+
+AS_IF([test "x$enable_dlp" = "xyes"], [
+    CPPFLAGS+=" -DUSE_TIZEN_FEATURE_DLP"
+])
+
+AM_CONDITIONAL(USE_TIZEN_FEATURE_DLP, test "x$enable_dlp" = "xyes")
+
 
 dnl **********************************************************************
 dnl Check for nghttp2
 dnl **********************************************************************
 
-AC_MSG_CHECKING([whether to build with nghttp2])
-OPT_H2="no"
+OPT_H2="yes"
+
+if test "x$disable_http" = "xyes"; then
+  # without HTTP, nghttp2 is no use
+  OPT_H2="no"
+fi
+
 AC_ARG_WITH(nghttp2,
 AC_HELP_STRING([--with-nghttp2=PATH],[Enable nghttp2 usage])
 AC_HELP_STRING([--without-nghttp2],[Disable nghttp2 usage]),
@@ -2742,24 +3394,16 @@ case "$OPT_H2" in
   no)
     dnl --without-nghttp2 option used
     want_h2="no"
-    AC_MSG_RESULT([no])
-    ;;
-  default)
-    dnl configure option not specified
-    want_h2="no"
-    AC_MSG_RESULT([no])
     ;;
   yes)
     dnl --with-nghttp2 option used without path
-    want_h2="yes"
+    want_h2="default"
     want_h2_path=""
-    AC_MSG_RESULT([yes])
     ;;
   *)
     dnl --with-nghttp2 option used with path
     want_h2="yes"
     want_h2_path="$withval/lib/pkgconfig"
-    AC_MSG_RESULT([yes ($withval)])
     ;;
 esac
 
@@ -2785,32 +3429,62 @@ if test X"$want_h2" != Xno; then
       $PKGCONFIG --libs-only-L libnghttp2`
     AC_MSG_NOTICE([-L is $LD_H2])
 
+    LDFLAGS="$LDFLAGS $LD_H2"
+    CPPFLAGS="$CPPFLAGS $CPP_H2"
+    LIBS="$LIB_H2 $LIBS"
+
+    # use nghttp2_option_set_no_recv_client_magic to require nghttp2
+    # >= 1.0.0
+    AC_CHECK_LIB(nghttp2, nghttp2_option_set_no_recv_client_magic,
+      [
+       AC_CHECK_HEADERS(nghttp2/nghttp2.h,
+          curl_h2_msg="enabled (nghttp2)"
+          NGHTTP2_ENABLED=1
+          AC_DEFINE(USE_NGHTTP2, 1, [if nghttp2 is in use])
+          AC_SUBST(USE_NGHTTP2, [1])
+       )
+      ],
+        dnl not found, revert back to clean variables
+        LDFLAGS=$CLEANLDFLAGS
+        CPPFLAGS=$CLEANCPPFLAGS
+        LIBS=$CLEANLIBS
+    )
+
   else
-    dnl To avoid link errors, we do not allow --libnghttp2 without
-    dnl a pkgconfig file
-    AC_MSG_ERROR([--with-nghttp2 was specified but could not find libnghttp2 pkg-config file.])
+    dnl no nghttp2 pkg-config found, deal with it
+    if test X"$want_h2" != Xdefault; then
+      dnl To avoid link errors, we do not allow --with-nghttp2 without
+      dnl a pkgconfig file
+      AC_MSG_ERROR([--with-nghttp2 was specified but could not find libnghttp2 pkg-config file.])
+    fi
   fi
 
-  LDFLAGS="$LDFLAGS $LD_H2"
-  CPPFLAGS="$CPPFLAGS $CPP_H2"
-  LIBS="$LIB_H2 $LIBS"
+fi
 
-  AC_CHECK_LIB(nghttp2, nghttp2_session_client_new,
-    [
-     AC_CHECK_HEADERS(nghttp2/nghttp2.h,
-        curl_h2_msg="enabled (nghttp2)"
-        NGHTTP2_ENABLED=1
-        AC_DEFINE(USE_NGHTTP2, 1, [if nghttp2 is in use])
-        AC_SUBST(USE_NGHTTP2, [1])
-     )
-    ],
-      dnl not found, revert back to clean variables
-      LDFLAGS=$CLEANLDFLAGS
-      CPPFLAGS=$CLEANCPPFLAGS
-      LIBS=$CLEANLIBS
-  )
+dnl **********************************************************************
+dnl Check for zsh completion path
+dnl **********************************************************************
 
-fi
+OPT_ZSH_FPATH=default
+AC_ARG_WITH(zsh-functions-dir,
+AC_HELP_STRING([--with-zsh-functions-dir=PATH],[Install zsh completions to PATH])
+AC_HELP_STRING([--without-zsh-functions-dir],[Do not install zsh completions]),
+  [OPT_ZSH_FPATH=$withval])
+case "$OPT_ZSH_FPATH" in
+  no)
+    dnl --without-zsh-functions-dir option used
+    ;;
+  default|yes)
+    dnl --with-zsh-functions-dir option used without path
+    ZSH_FUNCTIONS_DIR="$datarootdir/zsh/site-functions"
+    AC_SUBST(ZSH_FUNCTIONS_DIR)
+    ;;
+  *)
+    dnl --with-zsh-functions-dir option used with path
+    ZSH_FUNCTIONS_DIR="$withval"
+    AC_SUBST(ZSH_FUNCTIONS_DIR)
+    ;;
+esac
 
 dnl **********************************************************************
 dnl Back to "normal" configuring
@@ -2834,11 +3508,12 @@ AC_CHECK_HEADERS(
         assert.h \
         unistd.h \
         stdlib.h \
-        limits.h \
         arpa/inet.h \
         net/if.h \
         netinet/in.h \
+       netinet/in6.h \
         sys/un.h \
+        linux/tcp.h \
         netinet/tcp.h \
         netdb.h \
         sys/sockio.h \
@@ -2887,6 +3562,9 @@ dnl default includes
 #ifdef HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
+#ifdef HAVE_NETINET_IN6_H
+#include <netinet/in6.h>
+#endif
 #ifdef HAVE_SYS_UN_H
 #include <sys/un.h>
 #endif
@@ -2905,18 +3583,15 @@ AC_CHECK_SIZEOF(size_t)
 AC_CHECK_SIZEOF(long)
 AC_CHECK_SIZEOF(int)
 AC_CHECK_SIZEOF(short)
-CURL_CONFIGURE_LONG
 AC_CHECK_SIZEOF(time_t)
 AC_CHECK_SIZEOF(off_t)
 
-soname_bump=no
-if test x"$ac_cv_native_windows" != "xyes" &&
-   test $ac_cv_sizeof_off_t -ne $curl_sizeof_curl_off_t; then
-  AC_MSG_WARN([This libcurl built is probably not ABI compatible with previous])
-  AC_MSG_WARN([builds! You MUST read lib/README.curl_off_t to figure it out.])
-  soname_bump=yes
-fi
-
+o=$CPPFLAGS
+CPPFLAGS="-I$srcdir/include $CPPFLAGS"
+AC_CHECK_SIZEOF(curl_off_t, unused , [
+#include <curl/system.h>
+])
+CPPFLAGS=$o
 
 AC_CHECK_TYPE(long long,
    [AC_DEFINE(HAVE_LONGLONG, 1,
@@ -2957,6 +3632,23 @@ AC_CHECK_TYPE([bool],[
 #endif
 ])
 
+AC_MSG_CHECKING([if time_t is unsigned])
+AC_RUN_IFELSE([
+  AC_LANG_SOURCE([[
+  #include <time.h>
+  #include <limits.h>
+  time_t t = -1;
+  return (t > 0);
+  ]])] ,[
+  AC_MSG_RESULT([yes])
+  AC_DEFINE(HAVE_TIME_T_UNSIGNED, 1, [Define this if time_t is unsigned])
+],[
+  AC_MSG_RESULT([no])
+],[
+  dnl cross-compiling, most systems are unsigned
+  AC_MSG_RESULT([no])
+])
+
 CURL_CONFIGURE_CURL_SOCKLEN_T
 
 CURL_CONFIGURE_PULL_SYS_POLL
@@ -3033,22 +3725,21 @@ case $host in
     ;;
 esac
 
-AC_CHECK_FUNCS([fork \
-  geteuid \
+AC_CHECK_FUNCS([geteuid \
   getpass_r \
   getppid \
-  getprotobyname \
   getpwuid \
+  getpwuid_r \
   getrlimit \
   gettimeofday \
-  inet_addr \
-  perror \
+  if_nametoindex \
+  mach_absolute_time \
   pipe \
   setlocale \
   setmode \
   setrlimit \
-  uname \
-  utime
+  utime \
+  utimes
 ],[
 ],[
   func="$ac_func"
@@ -3076,7 +3767,7 @@ dnl and get the types of five of its arguments.
 CURL_CHECK_FUNC_GETNAMEINFO
 
 if test "$ipv6" = "yes"; then
-  if test "$ac_cv_func_getaddrinfo" = "yes"; then
+  if test "$curl_cv_func_getaddrinfo" = "yes"; then
     AC_DEFINE(ENABLE_IPV6, 1, [Define if you want to enable IPv6 support])
     IPV6_ENABLED=1
     AC_SUBST(IPV6_ENABLED)
@@ -3143,7 +3834,7 @@ AM_CONDITIONAL(USE_MANUAL, test x"$USE_MANUAL" = x1)
 CURL_CHECK_LIB_ARES
 AM_CONDITIONAL(USE_EMBEDDED_ARES, test x$embedded_ares = xyes)
 
-if test "x$ac_cv_native_windows" != "xyes" &&
+if test "x$curl_cv_native_windows" != "xyes" &&
    test "x$enable_shared" = "xyes"; then
   build_libhostname=yes
 else
@@ -3151,14 +3842,52 @@ else
 fi
 AM_CONDITIONAL(BUILD_LIBHOSTNAME, test x$build_libhostname = xyes)
 
-CURL_CHECK_OPTION_THREADED_RESOLVER
+if test "x$want_ares" != xyes; then
+  CURL_CHECK_OPTION_THREADED_RESOLVER
+fi
+
+dnl ************************************************************
+dnl disable POSIX threads
+dnl
+AC_MSG_CHECKING([whether to use POSIX threads for threaded resolver])
+AC_ARG_ENABLE(pthreads,
+AC_HELP_STRING([--enable-pthreads],
+               [Enable POSIX threads (default for threaded resolver)])
+AC_HELP_STRING([--disable-pthreads],[Disable POSIX threads]),
+[ case "$enableval" in
+  no)  AC_MSG_RESULT(no)
+       want_pthreads=no
+       ;;
+  *)   AC_MSG_RESULT(yes)
+       want_pthreads=yes
+       ;;
+  esac ], [
+       AC_MSG_RESULT(auto)
+       want_pthreads=auto
+       ]
+)
 
-if test "x$want_thres" = xyes && test "x$want_ares" = xyes; then
-  AC_MSG_ERROR(
-[Options --enable-threaded-resolver and --enable-ares are mutually exclusive])
+dnl turn off pthreads if rt is disabled
+if test "$want_pthreads" != "no"; then
+  if test "$want_pthreads" = "yes" && test "$dontwant_rt" = "yes"; then
+    AC_MSG_ERROR([options --enable-pthreads and --disable-rt are mutually exclusive])
+  fi
+  if test "$dontwant_rt" != "no"; then
+    dnl if --enable-pthreads was explicit then warn it's being ignored
+    if test "$want_pthreads" = "yes"; then
+      AC_MSG_WARN([--enable-pthreads Ignored since librt is disabled.])
+    fi
+    want_pthreads=no
+  fi
 fi
 
-if test "$want_thres" = "yes"; then
+dnl turn off pthreads if no threaded resolver
+if test "$want_pthreads" != "no" && test "$want_thres" != "yes"; then
+  want_pthreads=no
+fi
+
+dnl detect pthreads
+if test "$want_pthreads" != "no"; then
   AC_CHECK_HEADER(pthread.h,
     [ AC_DEFINE(HAVE_PTHREAD_H, 1, [if you have <pthread.h>])
       save_CFLAGS="$CFLAGS"
@@ -3180,11 +3909,24 @@ if test "$want_thres" = "yes"; then
         AC_DEFINE(USE_THREADS_POSIX, 1, [if you want POSIX threaded DNS lookup])
         curl_res_msg="POSIX threaded"
       fi
-
-
   ])
 fi
 
+dnl threaded resolver check
+if test "$want_thres" = "yes" && test "x$USE_THREADS_POSIX" != "x1"; then
+  if test "$want_pthreads" = "yes"; then
+    AC_MSG_ERROR([--enable-pthreads but pthreads was not found])
+  fi
+  dnl If native Windows fallback on Win32 threads since no POSIX threads
+  if test "$curl_cv_native_windows" = "yes"; then
+    USE_THREADS_WIN32=1
+    AC_DEFINE(USE_THREADS_WIN32, 1, [if you want Win32 threaded DNS lookup])
+    curl_res_msg="Win32 threaded"
+  else
+    AC_MSG_ERROR([Threaded resolver enabled but no thread library found])
+  fi
+fi
+
 dnl ************************************************************
 dnl disable verbose text strings
 dnl
@@ -3213,7 +3955,7 @@ AC_HELP_STRING([--enable-sspi],[Enable SSPI])
 AC_HELP_STRING([--disable-sspi],[Disable SSPI]),
 [ case "$enableval" in
   yes)
-       if test "$ac_cv_native_windows" = "yes"; then
+       if test "$curl_cv_native_windows" = "yes"; then
          AC_MSG_RESULT(yes)
          AC_DEFINE(USE_WINDOWS_SSPI, 1, [to enable SSPI support])
          AC_SUBST(USE_WINDOWS_SSPI, [1])
@@ -3284,13 +4026,46 @@ AC_HELP_STRING([--disable-tls-srp],[Disable TLS-SRP authentication]),
        want_tls_srp=yes
 )
 
-if test "$want_tls_srp" = "yes" && ( test "x$HAVE_GNUTLS_SRP" = "x1" || test "x$HAVE_SSLEAY_SRP" = "x1") ; then
+if test "$want_tls_srp" = "yes" && ( test "x$HAVE_GNUTLS_SRP" = "x1" || test "x$HAVE_OPENSSL_SRP" = "x1") ; then
    AC_DEFINE(USE_TLS_SRP, 1, [Use TLS-SRP authentication])
    USE_TLS_SRP=1
    curl_tls_srp_msg="enabled"
 fi
 
 dnl ************************************************************
+dnl disable Unix domain sockets support
+dnl
+AC_MSG_CHECKING([whether to enable Unix domain sockets])
+AC_ARG_ENABLE(unix-sockets,
+AC_HELP_STRING([--enable-unix-sockets],[Enable Unix domain sockets])
+AC_HELP_STRING([--disable-unix-sockets],[Disable Unix domain sockets]),
+[ case "$enableval" in
+  no)  AC_MSG_RESULT(no)
+       want_unix_sockets=no
+       ;;
+  *)   AC_MSG_RESULT(yes)
+       want_unix_sockets=yes
+       ;;
+  esac ], [
+       AC_MSG_RESULT(auto)
+       want_unix_sockets=auto
+       ]
+)
+if test "x$want_unix_sockets" != "xno"; then
+  AC_CHECK_MEMBER([struct sockaddr_un.sun_path], [
+    AC_DEFINE(USE_UNIX_SOCKETS, 1, [Use Unix domain sockets])
+    AC_SUBST(USE_UNIX_SOCKETS, [1])
+    curl_unix_sockets_msg="enabled"
+  ], [
+    if test "x$want_unix_sockets" = "xyes"; then
+      AC_MSG_ERROR([--enable-unix-sockets is not available on this platform!])
+    fi
+  ], [
+    #include <sys/un.h>
+  ])
+fi
+
+dnl ************************************************************
 dnl disable cookies support
 dnl
 AC_MSG_CHECKING([whether to enable support for cookies])
@@ -3313,26 +4088,6 @@ dnl hiding of library internal symbols
 dnl
 CURL_CONFIGURE_SYMBOL_HIDING
 
-dnl ************************************************************
-dnl enforce SONAME bump
-dnl
-
-AC_MSG_CHECKING([whether to enforce SONAME bump])
-AC_ARG_ENABLE(soname-bump,
-AC_HELP_STRING([--enable-soname-bump],[Enable enforced SONAME bump])
-AC_HELP_STRING([--disable-soname-bump],[Disable enforced SONAME bump]),
-[ case "$enableval" in
-  yes)   AC_MSG_RESULT(yes)
-         soname_bump=yes
-         ;;
-  *)
-         AC_MSG_RESULT(no)
-         ;;
-  esac ],
-        AC_MSG_RESULT($soname_bump)
-)
-AM_CONDITIONAL(SONAME_BUMP, test x$soname_bump = xyes)
-
 dnl
 dnl All the library dependencies put into $LIB apply to libcurl only.
 dnl
@@ -3365,7 +4120,7 @@ dnl For keeping supported features and protocols also in pkg-config file
 dnl since it is more cross-compile friendly than curl-config
 dnl
 
-if test "x$USE_SSLEAY" = "x1"; then
+if test "x$OPENSSL_ENABLED" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES SSL"
 elif test -n "$SSL_ENABLED"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES SSL"
@@ -3373,10 +4128,17 @@ fi
 if test "x$IPV6_ENABLED" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES IPv6"
 fi
+if test "x$USE_UNIX_SOCKETS" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES UnixSockets"
+fi
 if test "x$HAVE_LIBZ" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES libz"
 fi
-if test "x$USE_ARES" = "x1" -o "x$USE_THREADS_POSIX" = "x1"; then
+if test "x$HAVE_BROTLI" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES brotli"
+fi
+if test "x$USE_ARES" = "x1" -o "x$USE_THREADS_POSIX" = "x1" \
+                            -o "x$USE_THREADS_WIN32" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES AsynchDNS"
 fi
 if test "x$IDN_ENABLED" = "x1"; then
@@ -3385,17 +4147,38 @@ fi
 if test "x$USE_WINDOWS_SSPI" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES SSPI"
 fi
-if test "x$CURL_DISABLE_HTTP" != "x1" -a \
-       "x$CURL_DISABLE_CRYPTO_AUTH" != "x1"; then
-  if test "x$USE_SSLEAY" = "x1" -o "x$USE_WINDOWS_SSPI" = "x1" \
-      -o "x$GNUTLS_ENABLED" = "x1" -o "x$NSS_ENABLED" = "x1" \
-      -o "x$DARWINSSL_ENABLED" = "x1"; then
+
+if test "x$HAVE_GSSAPI" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES GSS-API"
+fi
+
+if test "x$curl_psl_msg" = "xyes"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES PSL"
+fi
+
+if test "x$CURL_DISABLE_CRYPTO_AUTH" != "x1" -a \
+    \( "x$HAVE_GSSAPI" = "x1" -o "x$USE_WINDOWS_SSPI" = "x1" \); then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES SPNEGO"
+fi
+
+if test "x$CURL_DISABLE_CRYPTO_AUTH" != "x1" -a \
+    \( "x$HAVE_GSSAPI" = "x1" -o "x$USE_WINDOWS_SSPI" = "x1" \); then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES Kerberos"
+fi
+
+if test "x$CURL_DISABLE_CRYPTO_AUTH" != "x1"; then
+  if test "x$OPENSSL_ENABLED" = "x1" -o "x$USE_WINDOWS_SSPI" = "x1" \
+      -o "x$GNUTLS_ENABLED" = "x1" -o "x$MBEDTLS_ENABLED" = "x1" \
+      -o "x$NSS_ENABLED" = "x1" -o "x$DARWINSSL_ENABLED" = "x1"; then
     SUPPORT_FEATURES="$SUPPORT_FEATURES NTLM"
-    if test "x$NTLM_WB_ENABLED" = "x1"; then
+
+    if test "x$CURL_DISABLE_HTTP" != "x1" -a \
+        "x$NTLM_WB_ENABLED" = "x1"; then
       SUPPORT_FEATURES="$SUPPORT_FEATURES NTLM_WB"
     fi
   fi
 fi
+
 if test "x$USE_TLS_SRP" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES TLS-SRP"
 fi
@@ -3404,6 +4187,15 @@ if test "x$USE_NGHTTP2" = "x1"; then
   SUPPORT_FEATURES="$SUPPORT_FEATURES HTTP2"
 fi
 
+if test "x$CURL_WITH_MULTI_SSL" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES MultiSSL"
+fi
+
+if test "x$OPENSSL_ENABLED" = "x1" -o "x$GNUTLS_ENABLED" = "x1" \
+    -o "x$NSS_ENABLED" = "x1"; then
+  SUPPORT_FEATURES="$SUPPORT_FEATURES HTTPS-proxy"
+fi
+
 AC_SUBST(SUPPORT_FEATURES)
 
 dnl For supported protocols in pkg-config file
@@ -3455,6 +4247,16 @@ if test "x$CURL_DISABLE_IMAP" != "x1"; then
     SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS IMAPS"
   fi
 fi
+if test "x$CURL_DISABLE_SMB" != "x1" \
+    -a "x$CURL_DISABLE_CRYPTO_AUTH" != "x1" \
+    -a \( "x$OPENSSL_ENABLED" = "x1" -o "x$USE_WINDOWS_SSPI" = "x1" \
+      -o "x$GNUTLS_ENABLED" = "x1" -o "x$MBEDTLS_ENABLED" = "x1" \
+      -o "x$NSS_ENABLED" = "x1" -o "x$DARWINSSL_ENABLED" = "x1" \); then
+  SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SMB"
+  if test "x$SSL_ENABLED" = "x1"; then
+    SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SMBS"
+  fi
+fi
 if test "x$CURL_DISABLE_SMTP" != "x1"; then
   SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SMTP"
   if test "x$SSL_ENABLED" = "x1"; then
@@ -3465,6 +4267,10 @@ if test "x$USE_LIBSSH2" = "x1"; then
   SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SCP"
   SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SFTP"
 fi
+if test "x$USE_LIBSSH" = "x1"; then
+  SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SCP"
+  SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS SFTP"
+fi
 if test "x$CURL_DISABLE_RTSP" != "x1"; then
   SUPPORT_PROTOCOLS="$SUPPORT_PROTOCOLS RTSP"
 fi
@@ -3496,6 +4302,9 @@ squeeze SUPPORT_PROTOCOLS
 
 XC_CHECK_BUILD_FLAGS
 
+SSL_BACKENDS=${ssl_backends}
+AC_SUBST(SSL_BACKENDS)
+
 if test "x$want_curldebug_assumed" = "xyes" &&
   test "x$want_curldebug" = "xyes" && test "x$USE_ARES" = "x1"; then
   ac_configure_args="$ac_configure_args --enable-curldebug"
@@ -3505,10 +4314,14 @@ AC_CONFIG_FILES([Makefile \
            docs/Makefile \
            docs/examples/Makefile \
            docs/libcurl/Makefile \
+           docs/libcurl/opts/Makefile \
+           docs/cmdline-opts/Makefile \
            include/Makefile \
            include/curl/Makefile \
            src/Makefile \
            lib/Makefile \
+           extensions/Makefile \
+           scripts/Makefile \
            lib/libcurl.vers \
            tests/Makefile \
            tests/certs/Makefile \
@@ -3549,35 +4362,27 @@ AC_MSG_NOTICE([Configured to build curl/libcurl:
   SSL support:      ${curl_ssl_msg}
   SSH support:      ${curl_ssh_msg}
   zlib support:     ${curl_zlib_msg}
+  brotli support:   ${curl_brotli_msg}
   GSS-API support:  ${curl_gss_msg}
-  SPNEGO support:   ${curl_spnego_msg}
   TLS-SRP support:  ${curl_tls_srp_msg}
   resolver:         ${curl_res_msg}
-  ipv6 support:     ${curl_ipv6_msg}
+  IPv6 support:     ${curl_ipv6_msg}
+  Unix sockets support: ${curl_unix_sockets_msg}
   IDN support:      ${curl_idn_msg}
   Build libcurl:    Shared=${enable_shared}, Static=${enable_static}
   Built-in manual:  ${curl_manual_msg}
   --libcurl option: ${curl_libcurl_msg}
   Verbose errors:   ${curl_verbose_msg}
   SSPI support:     ${curl_sspi_msg}
-  ca cert bundle:   ${ca}
-  ca cert path:     ${capath}
+  ca cert bundle:   ${ca}${ca_warning}
+  ca cert path:     ${capath}${capath_warning}
+  ca fallback:      ${with_ca_fallback}
   LDAP support:     ${curl_ldap_msg}
   LDAPS support:    ${curl_ldaps_msg}
   RTSP support:     ${curl_rtsp_msg}
   RTMP support:     ${curl_rtmp_msg}
   metalink support: ${curl_mtlnk_msg}
+  PSL support:      ${curl_psl_msg}
   HTTP2 support:    ${curl_h2_msg}
   Protocols:        ${SUPPORT_PROTOCOLS}
 ])
-
-if test "x$soname_bump" = "xyes"; then
-
-cat <<EOM
-  SONAME bump:     yes - WARNING: this library will be built with the SONAME
-                   number bumped due to (a detected) ABI breakage.
-                   See lib/README.curl_off_t for details on this.
-EOM
-
-fi
-