clutter: Generate keynames table

Infrastructure to provide a meta_accelerator_name and
avoid libmutter clients from depending on GTK for that.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2407>

clutter/clutter/gen-keyname-table.pl

@@ -0,0 +1,100 @@
+#!/usr/bin/perl -w
+# Slightly modified version of <https://gitlab.gnome.org/GNOME/gtk/-/blob/main/gdk/gen-keyname-table.pl>
+
+if (@ARGV != 1) {
+    die "Usage: gen-keyname-table.pl keynames.txt > keyname-table.h\n";
+}
+
+open IN, $ARGV[0] || die "Cannot open $ARGV[0]: $!\n";
+
+@keys = ();
+@translate = ();
+while (defined($_ = <IN>)) {
+    next if /^!/;
+    if (!/^\s*(0x[0-9a-f]+)\s+([\w_]*\S)\s+(1)?\s*$/) {
+	die "Cannot parse line $_";
+    }
+
+    push @keys, [$1, $2];
+
+    if (defined ($3)) {
+	push @translate, $2;
+    }
+}
+close IN;
+
+$offset = 0;
+
+$date = gmtime;
+
+print <<EOT;
+/* keyname-table.h: Generated by gen-keyname-table.pl from keynames.txt
+ *
+ *  Date: $date
+ *
+ * Do not edit.   
+ */
+static const char keynames[] =
+EOT
+
+for $key (@keys) {
+    $name = $key->[1];
+
+    if ($offset != 0) {
+	print qq(\n);
+    }
+    print qq(  "$name\\0");
+
+    $key->[3] = $offset;
+    $offset += length($name) + 1;
+}
+
+print ";\n\n";
+
+print <<EOT;
+typedef struct {
+    unsigned int keyval;
+    unsigned int offset;
+} clutter_key;
+
+static const clutter_key clutter_keys_by_keyval[] = {
+EOT
+
+$i = 0;
+for $key (@keys) {
+    $keyval = $key->[0];
+    $name = $key->[1];
+    $offset = $key->[3];
+
+    if ($i != 0) {
+	print ",\n";
+    }
+    print "  { $keyval, $offset }";
+    $i++;
+}
+
+print "\n};\n\n";
+
+@keys = sort { $a->[1] cmp $b->[1] } @keys;
+
+
+print <<EOT;
+static const clutter_key clutter_keys_by_name[] = {
+EOT
+
+$i = 0;
+for $key (@keys) {
+    $keyval = $key->[0];
+    $name = $key->[1];
+    $offset = $key->[3];
+
+    if ($i != 0) {
+	print ",\n";
+    }
+    print "  { $keyval, $offset }";
+    $i++;
+}
+
+print <<EOT;
+};
+EOT