livecd-iso-to-disk.sh in livecd-tools-027 needs a small fix (for my previous patch) to show the correct amount of space needed to be freed before it can fit a new liveusb image + overlays. This is only noticed when you're replacing an existing an usblive with another, and not --format'ing or initially empty.

patch summary:
-  echo "= To fit, free or decrease requested size total by:  $(($tba - $free + $tbd))"
+  echo "= To fit, free or decrease requested size total by:  $(($tba - $free - $tbd))"



Example reproduced below:


[root@nano tmp]# qemu-img create usb.img 2G
Formatting 'usb.img', fmt=raw, size=2097152 kB
[root@nano tmp]# losetup /dev/loop0 usb.img
[root@nano tmp]# mkfs.vfat /dev/loop0
mkfs.vfat 3.0.1 (23 Nov 2008)
Loop device does not match a floppy size, using default hd params
[root@nano tmp]# ./tools_livecd-iso-to-disk.sh.orig --noverify --overlay-size-mb 2047 /0safe/iso-images/F12-Snap2-i686-Live/F12-Snap2-i686-Live.iso /dev/loop0
Unable to fit live image + overlay on available space on USB stick
+ Size of live image:  634
+ Overlay size:  2047
---------------------------
= Requested:  2681
- Available:  2044
---------------------------
= To fit, free or decrease requested size total by:  637
Cleaning up to exit...
[root@nano tmp]# ./tools_livecd-iso-to-disk.sh.orig --noverify --overlay-size-mb 1024 /0safe/iso-images/F12-Snap2-i686-Live/F12-Snap2-i686-Live.iso /dev/loop0
Copying live image to USB stick
Updating boot config file
Initializing persistent overlay file
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 5.04073 s, 213 MB/s
Installing boot loader
USB stick set up as live image!
[root@nano tmp]# ./tools_livecd-iso-to-disk.sh.orig --noverify --overlay-size-mb 2047 /0safe/iso-images/F12-Snap2-i686-Live/F12-Snap2-i686-Live.iso /dev/loop0
Unable to fit live image + overlay on available space on USB stick
+ Size of live image:  634
+ Overlay size:  2047
---------------------------
= Requested:  2681
- Available:  2030
---------------------------
= To fit, free or decrease requested size total by:  3967
Cleaning up to exit...

###### wrong ----------------------------------------^^^^
###### compared with the fix:

[root@nano tmp]# ./tools_livecd-iso-to-disk.sh --noverify --overlay-size-mb 2047 /0safe/iso-images/F12-Snap2-i686-Live/F12-Snap2-i686-Live.iso /dev/loop0
Unable to fit live image + overlay on available space on USB stick
+ Size of live image:  634
+ Overlay size:  2047
---------------------------
= Requested:  2681
- Available:  2030
---------------------------
= To fit, free or decrease requested size total by:  651

###### right ----------------------------------------^^^