scripts/archive-source: find directory name for subprojects

Rust subprojects have the semantic version (followed by -rs) in the subproject
name, but the full version (without -rs) is used by crates.io for the root
directory of the tarball.  Teach scripts/archive-source.sh to look for the
root directory name in wrap files.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/scripts/archive-source.sh b/scripts/archive-source.sh
index 65af806..9d9b2e2 100755
--- a/scripts/archive-source.sh
+++ b/scripts/archive-source.sh
@@ -48,13 +48,34 @@
     echo "$retval"
 }
 
+function subproject_dir() {
+    if test ! -f "subprojects/$1.wrap"; then
+      error "scripts/archive-source.sh should only process wrap subprojects"
+    fi
+
+    # Print the directory key of the wrap file, defaulting to the
+    # subproject name.  The wrap file is in ini format and should
+    # have a single section only.  There should be only one section
+    # named "[wrap-*]", which helps keeping the script simple.
+    local dir
+    dir=$(sed -n \
+      -e '/^\[wrap-[a-z][a-z]*\]$/,/^\[/{' \
+      -e    '/^directory *= */!b' \
+      -e    's///p' \
+      -e    'q' \
+      -e '}' \
+      "subprojects/$1.wrap")
+
+    echo "${dir:-$1}"
+}
+
 git archive --format tar "$(tree_ish)" > "$tar_file"
 test $? -ne 0 && error "failed to archive qemu"
 
 for sp in $subprojects; do
     meson subprojects download $sp
     test $? -ne 0 && error "failed to download subproject $sp"
-    tar --append --file "$tar_file" --exclude=.git subprojects/$sp
+    tar --append --file "$tar_file" --exclude=.git subprojects/"$(subproject_dir $sp)"
     test $? -ne 0 && error "failed to append subproject $sp to $tar_file"
 done
 exit 0