1 files changed, 34 insertions, 0 deletions
diff --git a/scripts/remove-boot-splash b/scripts/remove-boot-splash
new file mode 100644
index 0000000..e63c3b5
--- /dev/null
+++ b/scripts/remove-boot-splash
@@ -0,0 +1,34 @@
+#!/usr/bin/perl
+
+@ARGV == 1 or die "usage: remove-splash <initrd>\n";
+
+my $magic = 'BOOTSPL3';
+my $buffer_size = 15;
+
+my ($initrd) = @ARGV;
+open(my $F, "+< $initrd") or die "can't open $initrd: $!\n";
+
+while (1) {
+    my $got = read($F, my $buffer, $buffer_size);
+    $got > length($magic) or last;
+
+    my $index = index($buffer, $magic);
+    if ($index >= 0) {
+	my $offset = $index + tell($F) - $got;
+
+	seek($F, $offset + 12, 0) && read($F, my $tmp, 4) or last;
+	my $splash_size = unpack("V", $tmp) + 38;
+
+	my $initrd_size = seek($F, 0, 2) && tell($F);
+	
+	if ($offset + $splash_size == $initrd_size) {
+	    truncate($F, $offset);
+	    exit 0;
+	} else {
+	    warn "bootsplash found at offset $offset, but it is not at the end ($offset + $splash_size != $initrd_size)\n";
+	}
+    }
+    seek($F, -length($magic), 1); # handle the case BOOTSPL3 when overlaps between buffers
+}
+
+warn "bootsplash not found in $initrd\n";