configure: check for submodules if --with-git-submodules=ignore

Right now --with-git-submodules=ignore has a subtle difference from
just running without a .git directory, in that it does not check
that submodule sources actually exist.  Move the check for
ui/keycodemapdb/README so that it happens even if the user
specified --with-git-submodules=ignore, with a customized
error message that is more suitable for this situation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 22 insertions, 18 deletions

diff --git a/configure b/configure
index 808874cb31..f32c6f1a26 100755
--- a/configure
+++ b/configure
@@ -260,24 +260,6 @@ then
 else
     git_submodules_action="ignore"
     git_submodules=""
-
-    if ! test -f "$source_path/ui/keycodemapdb/README"
-    then
-        echo
-        echo "ERROR: missing file $source_path/ui/keycodemapdb/README"
-        echo
-        echo "This is not a GIT checkout but module content appears to"
-        echo "be missing. Do not use 'git archive' or GitHub download links"
-        echo "to acquire QEMU source archives. Non-GIT builds are only"
-        echo "supported with source archives linked from:"
-        echo
-        echo "  https://www.qemu.org/download/#source"
-        echo
-        echo "Developers working with GIT can use scripts/archive-source.sh"
-        echo "if they need to create valid source archives."
-        echo
-        exit 1
-    fi
 fi
 git="git"
 
@@ -1591,6 +1573,28 @@ case $git_submodules_action in
         fi
     ;;
     ignore)
+        if ! test -f "$source_path/ui/keycodemapdb/README"
+        then
+            echo
+            echo "ERROR: missing GIT submodules"
+            echo
+            if test -e "$source_path/.git"; then
+                echo "--with-git-submodules=ignore specified but submodules were not"
+                echo "checked out.  Please initialize and update submodules."
+            else
+                echo "This is not a GIT checkout but module content appears to"
+                echo "be missing. Do not use 'git archive' or GitHub download links"
+                echo "to acquire QEMU source archives. Non-GIT builds are only"
+                echo "supported with source archives linked from:"
+                echo
+                echo "  https://www.qemu.org/download/#source"
+                echo
+                echo "Developers working with GIT can use scripts/archive-source.sh"
+                echo "if they need to create valid source archives."
+            fi
+            echo
+            exit 1
+        fi
     ;;
     *)
         echo "ERROR: invalid --with-git-submodules= value '$git_submodules_action'"