Don't consider zero-size disks to exist.

(Crossport from win0405.)

diff --git a/src/utils/pintos b/src/utils/pintos
index a86e8de282973d2a6f9f5d209b2e52a34618d045..40a240ce974a66c0d590597be4bed25bed0e52dd 100755 (executable)
--- a/src/utils/pintos
+++ b/src/utils/pintos
@@ -23,17 +23,17 @@ GetOptions ("sim=s" => sub { set_sim (@_) },
            "no-debug" => sub { set_debug ("no-debug") },
            "monitor" => sub { set_debug ("monitor") },
            "gdb" => sub { set_debug ("gdb") },
-           
+
            "run|get|put|make-disk" => \&cmd_option,
-           
+
            "m|memory=i" => \$mem,
            "j|jitter=i" => sub { set_jitter (@_) },
            "r|realtime" => sub { set_realtime () },
-           
+
            "v|no-vga" => sub { set_vga ('none'); },
            "s|no-serial" => sub { $serial_out = 0; },
            "t|terminal" => sub { set_vga ('terminal'); },
-           
+
            "h|help" => sub { usage (0); },
 
            "0|os-disk|disk-0|hda=s" => \$disks[0],
@@ -113,7 +113,7 @@ if ($cmd eq 'run') {
     # Create scratch disk from file.
     die "$hostfn: $!\n" if ! -e $hostfn;
     my ($size) = -s _;
-    if ($size) { 
+    if ($size) {
        copy_pad ($hostfn, "scratch.dsk", 512);
     } else {
        open (SCRATCH, ">scratch.dsk") or die "scratch.dsk: create: $!\n";
@@ -214,8 +214,9 @@ sub run_vm {
     our (@disks);
 
     die "$disks[0]: can't find OS disk\n" if ! -e $disks[0];
+    die "$disks[0]: OS disk cannot have zero size\n" if ! -s $disks[0];
     for my $i (1...3) {
-       undef $disks[$i] if ! -e $disks[$i];
+       undef $disks[$i] if ! -s $disks[$i];
     }
 
     if (my ($project) = `pwd` =~ /\b(threads|userprog|vm|filesys)\b/) {