Initial commit

Author: meithecatte

LICENSE

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+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+                    Version 2, December 2004
+
+ Copyright (C) 2004 Sam Hocevar <[email protected]>
+
+ Everyone is permitted to copy and distribute verbatim or modified
+ copies of this license document, and changing it is allowed as long
+ as the name is changed.
+
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. You just DO WHAT THE FUCK YOU WANT TO.

README.md

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+# cursedfs
+
+Make a disk image formatted with both ext2 and FAT, at once.
+
+```bash
+~/cursedfs% wget 'https://github.com/NieDzejkob/cursedfs/releases/download/v1.0/cursed.img'
+~/cursedfs% sudo mount -o loop -t ext2 cursed.img mountpoint/
+~/cursedfs% ls mountpoint/
+mkfs.cursed
+~/cursedfs% sudo umount mountpoint/
+~/cursedfs% sudo mount -o loop -t msdos cursed.img mountpoint/
+~/cursedfs% ls mountpoint/
+gudnuse.ogg
+```
+
+# Why?
+
+[I got nerd-sniped](https://twitter.com/Foone/status/1217162186130198529?s=20)
+
+# How?
+
+It turns out this is surprisingly simple to do: just create a FAT volume with a
+lot of reserved sectors and put the ext2 into the reserved sectors. This works
+because the filesystems choose different places to put their superblock: FAT
+uses the very first sector, while ext2 leaves the first kilobyte unused.

mkfs.cursed

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+#!/bin/sh
+
+SIZE_EXT2=128 # sectors, max is 65535
+
+set -euxo pipefail
+EXT2_TMP="$(mktemp)"
+trap "rm $EXT2_TMP" EXIT
+
+truncate -s 4M cursed.img
+truncate -s "$((512*$SIZE_EXT2))" $EXT2_TMP
+mkfs.ext2 $EXT2_TMP
+mkfs.fat -R $SIZE_EXT2 cursed.img
+dd if=$EXT2_TMP of=cursed.img bs=512 skip=1 seek=1 conv=notrunc