configure: prepare for auto-generated option parsing

Prepare the configure script and Makefile for automatically generated
help and parsing.

Because we need to run the script to generate the full help, we
cannot rely on the user supplying the path to a Python interpreter
with --python; therefore, the introspection output is parsed into
shell functions and stored in scripts/.  The converter is written
in Python as standard for QEMU, and this commit contains a stub.

Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20211007130829.632254-18-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 22 insertions, 9 deletions

diff --git a/configure b/configure
index 2ec410378e..8eb0ef160f 100755
--- a/configure
+++ b/configure
@@ -789,6 +789,18 @@ fi
 
 werror=""
 
+. $source_path/scripts/meson-buildoptions.sh
+
+meson_options=
+meson_option_parse() {
+  meson_options="$meson_options $(_meson_option_parse "$@")"
+  if test $? -eq 1; then
+    echo "ERROR: unknown option $1"
+    echo "Try '$0 --help' for more information"
+    exit 1
+  fi
+}
+
 for opt do
   optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
   case "$opt" in
@@ -1548,6 +1560,8 @@ for opt do
   ;;
   --disable-slirp-smbd) slirp_smbd=no
   ;;
+  --enable-* | --disable-*) meson_option_parse "$opt" "$optarg"
+  ;;
   *)
       echo "ERROR: unknown option $opt"
       echo "Try '$0 --help' for more information"
@@ -1804,11 +1818,9 @@ Advanced options (experts only):
                            enable plugins via shared library loading
   --disable-containers     don't use containers for cross-building
   --gdb=GDB-path           gdb to use for gdbstub tests [$gdb_bin]
-
-Optional features, enabled with --enable-FEATURE and
-disabled with --disable-FEATURE, default is enabled if available
-(unless built with --without-default-features):
-
+EOF
+  meson_options_help
+cat << EOF
   system          all system emulation targets
   user            supported user emulation targets
   linux-user      all linux usermode emulation targets
@@ -4489,7 +4501,8 @@ if test "$skip_meson" = no; then
   mv $cross config-meson.cross
 
   rm -rf meson-private meson-info meson-logs
-  NINJA=$ninja $meson setup \
+  run_meson() {
+    NINJA=$ninja $meson setup \
         --prefix "$prefix" \
         --libdir "$libdir" \
         --libexecdir "$libexecdir" \
@@ -4534,9 +4547,9 @@ if test "$skip_meson" = no; then
         -Dpa=$pa -Daudio_drv_list=$audio_drv_list -Dtcg_interpreter=$tcg_interpreter \
         -Dtrace_backends=$trace_backends -Dtrace_file=$trace_file -Dlinux_aio=$linux_aio \
         -Dnetmap=$netmap -Dvde=$vde \
-        $cross_arg \
-        "$PWD" "$source_path"
-
+        "$@" $cross_arg "$PWD" "$source_path"
+  }
+  eval run_meson $meson_options
   if test "$?" -ne 0 ; then
       error_exit "meson setup failed"
   fi