WASM: add initial support for Emscripten cross build

- configure with:
- --host=wasm64-local-emscripten
- had to make a few externals optional, so adding:
- --disable-nss
- --disable-cmis
- --disable-curl

Change-Id: I48d1c73d2675ad2e2beaf2c341578199efbd24ee
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/111130
Tested-by: Jenkins
Reviewed-by: Thorsten Behrens <thorsten.behrens@allotropia.de>

1 files changed, 122 insertions, 18 deletions

diff --git a/configure.ac b/configure.ac
index 1b0521624ac2..e5ce5560c661 100644
--- a/configure.ac
+++ b/configure.ac
@@ -804,6 +804,8 @@ dnl Sequential to keep the logic very simple
 dnl These values may be checked and reset later.
 dnl ===================================================================
 #defaults unless the os test overrides this:
+test_cmis=yes
+test_curl=yes
 test_randr=yes
 test_xrender=yes
 test_cups=yes
@@ -957,6 +959,7 @@ darwin*|macos*) # macOS
 ;;
 
 ios*) # iOS
+    test_cmis=no
     test_randr=no
     test_xrender=no
     test_freetype=no
@@ -1104,6 +1107,29 @@ haiku*)
     _os=Haiku
     ;;
 
+emscripten)
+    build_gstreamer_1_0=no
+    enable_lpsolve=no
+    enable_report_builder=no
+    with_theme="breeze"
+    test_cmis=no
+    test_cups=no
+    test_curl=no
+    test_dbus=no
+    test_fontconfig=no
+    test_freetype=no
+    test_gtk=no
+    test_randr=no
+    test_xrender=no
+    enable_postgresql_sdbc=no
+    enable_firebird_sdbc=no
+    enable_mariadb_sdbc=no
+    with_system_zlib=no
+    _os=Emscripten
+
+    BUILD_TYPE="$BUILD_TYPE FONTCONFIG FREETYPE"
+    ;;
+
 *)
     AC_MSG_ERROR([$host_os operating system is not suitable to build LibreOffice for!])
     ;;
@@ -1254,10 +1280,24 @@ if test $_os != "WINNT"; then
 fi
 AC_SUBST(DLOPEN_LIBS)
 
-AC_ARG_ENABLE(ios-simulator,
-    AS_HELP_STRING([--enable-ios-simulator],
-        [build for iOS simulator])
-)
+dnl ===================================================================
+dnl Sanity checks for Emscripten SDK setup
+dnl ===================================================================
+
+if test "$_os" = "Emscripten"; then
+    EMSCRIPTEN_ERROR=0
+    if ! which emconfigure >/dev/null 2>&1; then
+        AC_MSG_WARN([emconfigure must be in your \$PATH])
+        EMSCRIPTEN_ERROR=1
+    fi
+    if test -z "$EMMAKEN_JUST_CONFIGURE"; then
+	AC_MSG_WARN(["\$EMMAKEN_JUST_CONFIGURE wasn't set by emconfigure. Prefix configure or use autogen.sh])
+        EMSCRIPTEN_ERROR=1
+    fi
+    if test $EMSCRIPTEN_ERROR -ne 0; then
+        AC_MSG_ERROR(["Please fix your EMSDK setup to build with Emscripten!"])
+    fi
+fi
 
 ###############################################################################
 # Extensions switches --enable/--disable
@@ -1272,6 +1312,11 @@ AC_ARG_ENABLE(ios-simulator,
 # if you use --disable-extension-integration. Is that really the
 # case?
 
+AC_ARG_ENABLE(ios-simulator,
+    AS_HELP_STRING([--enable-ios-simulator],
+        [build for iOS simulator])
+)
+
 libo_FUZZ_ARG_ENABLE(extension-integration,
     AS_HELP_STRING([--disable-extension-integration],
         [Disable integration of the built extensions in the installer of the
@@ -1462,7 +1507,8 @@ libo_FUZZ_ARG_ENABLE(optimized,
         [Whether to compile with optimization flags.
          By default, disabled for --enable-debug and --enable-dbgutil, enabled
          otherwise. Using 'debug' will try to use only optimizations that should
-         not interfere with debugging.]))
+         not interfere with debugging. For Emscripten we default to optimized (-O1)
+         debug build, as otherwise biaries become too large.]))
 
 libo_FUZZ_ARG_ENABLE(runtime-optimizations,
     AS_HELP_STRING([--disable-runtime-optimizations],
@@ -1789,6 +1835,13 @@ libo_FUZZ_ARG_ENABLE(cipher-openssl-backend,
         [Enable using OpenSSL as the actual implementation of the rtl/cipher.h functionality.
          Requires --enable-openssl.]))
 
+AC_ARG_ENABLE(nss,
+    AS_HELP_STRING([--disable-nss],
+        [Disable using NSS. If disabled,
+         components will either use GNUTLS or openssl. Work in progress,
+         use only if you are hacking on it.]),
+,enable_nss=yes)
+
 AC_ARG_ENABLE(library-bin-tar,
     AS_HELP_STRING([--enable-library-bin-tar],
         [Enable the building and reused of tarball of binary build for some 'external' libraries.
@@ -1832,6 +1885,16 @@ libo_FUZZ_ARG_ENABLE(librelogo,
         [Do not build LibreLogo.]),
 ,enable_librelogo=yes)
 
+AC_ARG_ENABLE(cmis,
+    AS_HELP_STRING([--disable-cmis],
+        [Disable CMIS support.]),
+,enable_cmis=yes)
+
+AC_ARG_ENABLE(curl,
+    AS_HELP_STRING([--disable-curl],
+        [Disable CURL support.]),
+,enable_curl=yes)
+
 dnl ===================================================================
 dnl Optional Packages (--with/without-)
 dnl ===================================================================
@@ -2817,7 +2880,7 @@ dnl "desktop" one but a "mobile" one, we are always cross-compiling.
 dnl Note the direction of the implication; there is no assumption that
 dnl cross-compiling would imply a non-desktop OS.
 
-if test $_os != iOS -a $_os != Android -a "$enable_fuzzers" != "yes"; then
+if test $_os != iOS -a $_os != Android -a $_os != Emscripten -a "$enable_fuzzers" != "yes"; then
     BUILD_TYPE="$BUILD_TYPE DESKTOP"
     AC_DEFINE(HAVE_FEATURE_DESKTOP)
     AC_DEFINE(HAVE_FEATURE_MULTIUSER_ENVIRONMENT)
@@ -2868,7 +2931,7 @@ fi
 if test -z "$enable_scripting"; then
     # Disable scripting for iOS unless specifically overridden
     # with --enable-scripting.
-    if test $_os != iOS; then
+    if test $_os != iOS -o $_os = Emscripten; then
         enable_scripting=yes
     fi
 fi
@@ -2882,7 +2945,7 @@ else
     SCPDEFS="$SCPDEFS -DDISABLE_SCRIPTING"
 fi
 
-if test $_os = iOS -o $_os = Android; then
+if test $_os = iOS -o $_os = Android -o $_os = Emscripten; then
     # Disable dynamic_loading always for iOS and Android
     enable_dynamic_loading=no
 elif test -z "$enable_dynamic_loading"; then
@@ -4105,6 +4168,8 @@ if test "$COM_IS_CLANG" = TRUE; then
         [my_apple_clang=yes],[my_apple_clang=])
     if test "$my_apple_clang" = yes; then
         AC_MSG_RESULT([assumed yes (Apple Clang)])
+    elif test "$_os" = Emscripten; then
+        AC_MSG_RESULT([assumed yes (Emscripten Clang)])
     else
         if test "$_os" = WINNT; then
             dnl In which case, assume clang-cl:
@@ -4186,7 +4251,7 @@ fi
 # ===================================================================
 
 HAVE_GCC_GGDB2=
-if test "$GCC" = "yes"; then
+if test "$GCC" = "yes" -a "$_os" != "Emscripten"; then
     AC_MSG_CHECKING([whether $CC_BASE supports -ggdb2])
     save_CFLAGS=$CFLAGS
     CFLAGS="$CFLAGS -Werror -ggdb2"
@@ -4414,7 +4479,7 @@ fi
 AC_SUBST(USE_LD)
 
 HAVE_LD_BSYMBOLIC_FUNCTIONS=
-if test "$GCC" = "yes"; then
+if test "$GCC" = "yes" -a "$_os" != Emscripten ; then
     AC_MSG_CHECKING([for -Bsymbolic-functions linker support])
     bsymbolic_functions_ldflags_save=$LDFLAGS
     LDFLAGS="$LDFLAGS -Wl,-Bsymbolic-functions"
@@ -4600,7 +4665,7 @@ elif test "$enable_optimized" = debug; then
     ENABLE_OPTIMIZED_DEBUG=TRUE
     AC_MSG_RESULT([yes (debug)])
     HAVE_GCC_OG=
-    if test "$GCC" = "yes"; then
+    if test "$GCC" = "yes" -a "$_os" != "Emscripten"; then
         AC_MSG_CHECKING([whether $CC_BASE supports -Og])
         save_CFLAGS=$CFLAGS
         CFLAGS="$CFLAGS -Werror -Og"
@@ -4612,7 +4677,7 @@ elif test "$enable_optimized" = debug; then
             AC_MSG_RESULT([no])
         fi
     fi
-    if test -z "$HAVE_GCC_OG"; then
+    if test -z "$HAVE_GCC_OG" -a "$_os" != "Emscripten"; then
         AC_MSG_ERROR([The compiler does not support optimizations suitable for debugging.])
     fi
 else
@@ -5055,6 +5120,25 @@ solaris*)
     SOLARINC="$SOLARINC -I/usr/local/include"
     ;;
 
+emscripten*)
+    COM=GCC
+    USING_X11=
+    OS=EMSCRIPTEN
+    RTL_OS=Emscripten
+    P_SEP=:
+
+    case "$host_cpu" in
+    wasm32|wasm64)
+        ;;
+    *)
+        AC_MSG_ERROR([Unsupported host_cpu $host_cpu for host_os $host_os])
+        ;;
+    esac
+    CPUNAME=INTEL
+    RTL_ARCH=x86
+    PLATFORMID=linux_x86
+    ;;
+
 *)
     AC_MSG_ERROR([$host_os operating system is not suitable to build LibreOffice for!])
     ;;
@@ -5179,9 +5263,10 @@ if test "$cross_compiling" = "yes"; then
     (
     unset COM USING_X11 OS CPUNAME
     unset CC CXX SYSBASE CFLAGS
-    unset AR NM OBJDUMP PKG_CONFIG RANLIB READELF STRIP
+    unset AR LD NM OBJDUMP PKG_CONFIG RANLIB READELF STRIP
     unset CPPUNIT_CFLAGS CPPUNIT_LIBS
-    unset LIBXML_CFLAGS LIBXML_LIBS LIBXSLT_CFLAGS LIBXSLT_LIBS XSLTPROC PKG_CONFIG_LIBDIR
+    unset LIBXML_CFLAGS LIBXML_LIBS LIBXSLT_CFLAGS LIBXSLT_LIBS XSLTPROC
+    unset PKG_CONFIG_LIBDIR PKG_CONFIG_PATH
     if test -n "$CC_FOR_BUILD"; then
         export CC="$CC_FOR_BUILD"
         CC_BASE=`first_arg_basename "$CC"`
@@ -5193,6 +5278,7 @@ if test "$cross_compiling" = "yes"; then
     test -n "$PKG_CONFIG_FOR_BUILD" && export PKG_CONFIG="$PKG_CONFIG_FOR_BUILD"
     cd CONF-FOR-BUILD
 
+    # Handle host configuration, which affects the cross-toolset too
     sub_conf_opts=""
     test -n "$enable_ccache" && sub_conf_opts="$sub_conf_opts --enable-ccache=$enable_ccache"
     test -n "$with_ant_home" && sub_conf_opts="$sub_conf_opts --with-ant-home=$with_ant_home"
@@ -5227,6 +5313,7 @@ if test "$cross_compiling" = "yes"; then
         --disable-gstreamer-1-0 \
         --disable-gtk3 \
         --disable-mariadb-sdbc \
+        --disable-nss \
         --disable-online-update \
         --disable-opencl \
         --disable-pdfimport \
@@ -5249,7 +5336,9 @@ if test "$cross_compiling" = "yes"; then
     PERMITTED_BUILD_TARGETS="
         AVMEDIA
         BOOST
+        CAIRO
         CLUCENE
+        CURL
         DBCONNECTIVITY
         DESKTOP
         DYNLOADING
@@ -6062,9 +6151,12 @@ if test "$_os" != "WINNT"; then
 fi
 AC_SUBST(AR)
 AC_SUBST(DLLTOOL)
+AC_SUBST(LD)
 AC_SUBST(NM)
 AC_SUBST(OBJDUMP)
 AC_SUBST(PKG_CONFIG)
+AC_SUBST(PKG_CONFIG_PATH)
+AC_SUBST(PKG_CONFIG_LIBDIR)
 AC_SUBST(RANLIB)
 AC_SUBST(READELF)
 AC_SUBST(STRIP)
@@ -7054,7 +7146,7 @@ dnl ===================================================================
 dnl Check for system libcmis
 dnl ===================================================================
 # libcmis requires curl and we can't build curl for iOS
-if test $_os != iOS; then
+if test "$test_cmis" = "yes" -a "$enable_cmis" = "yes"; then
     libo_CHECK_SYSTEM_MODULE([libcmis],[LIBCMIS],[libcmis-0.5 >= 0.5.2])
     ENABLE_LIBCMIS=TRUE
 else
@@ -9207,6 +9299,9 @@ if test "$with_system_libxml" = "auto"; then
     WINNT|iOS|Android)
         with_system_libxml="$with_system_libs"
         ;;
+    Emscripten)
+        with_system_libxml=no
+        ;;
     *)
         if test "$enable_fuzzers" != "yes"; then
             with_system_libxml=yes
@@ -9349,7 +9444,11 @@ no|disable)
         # Python is required to build LibreOffice. In theory we could separate the build-time Python
         # requirement from the choice whether to include Python stuff in the installer, but why
         # bother?
-        AC_MSG_ERROR([Python is required at build time.])
+        if test "$cross_compiling" = yes; then
+            enable_python=system
+        else
+            AC_MSG_ERROR([Python is required at build time.])
+        fi
     fi
     enable_python=no
     AC_MSG_RESULT([none])
@@ -10037,7 +10136,7 @@ if test "$with_system_curl" = "auto"; then
     with_system_curl="$with_system_libs"
 fi
 
-if test "$with_system_curl" = "yes"; then
+if test "$test_curl" = "yes" -a "$enable_curl" = "yes" -a "$with_system_curl" = "yes"; then
     AC_MSG_RESULT([external])
     SYSTEM_CURL=TRUE
 
@@ -10069,6 +10168,8 @@ if test "$with_system_curl" = "yes"; then
     fi
 
     ENABLE_CURL=TRUE
+elif test "$test_curl" = "no"; then
+    AC_MSG_RESULT([none])
 else
     AC_MSG_RESULT([internal])
     SYSTEM_CURL=
@@ -10211,7 +10312,7 @@ AC_SUBST(SYSTEM_OPENLDAP)
 dnl ===================================================================
 dnl Check for system NSS
 dnl ===================================================================
-if test "$enable_fuzzers" != "yes"; then
+if test "$enable_fuzzers" != "yes" -a "$enable_nss" = "yes"; then
     libo_CHECK_SYSTEM_MODULE([nss],[NSS],[nss >= 3.9.3 nspr >= 4.8])
     AC_DEFINE(HAVE_FEATURE_NSS)
     ENABLE_NSS="TRUE"
@@ -11372,6 +11473,8 @@ if test -z "$build_vcl_plugins"; then
     build_vcl_plugins="none"
 fi
 AC_MSG_NOTICE([VCLplugs to be built: $build_vcl_plugins])
+VCL_PLUGIN_INFO=$R
+AC_SUBST([VCL_PLUGIN_INFO])
 
 dnl ===================================================================
 dnl check for dbus support
@@ -12412,6 +12515,7 @@ MOC5="moc"
 QT5_GOBJECT_CFLAGS=""
 QT5_GOBJECT_LIBS=""
 QT5_HAVE_GOBJECT=""
+QT5_PLATFORMS_SRCDIR=""
 if test \( "$test_kf5" = "yes" -a "$ENABLE_KF5" = "TRUE" \) -o \
         \( "$test_qt5" = "yes" -a "$ENABLE_QT5" = "TRUE" \) -o \
         \( "$test_gtk3_kde5" = "yes" -a "$ENABLE_GTK3_KDE5" = "TRUE" \)