fatr not working with new fat12 images

[kallisti5]

Creating a new 16MiB image, attempting to inject 84K file via fatr:

kallisti5@eris fatr :( $ dd if=/dev/zero of=/home/kallisti5/fat12.img bs=$((1024*1024)) count=16
16+0 records in
16+0 records out
16777216 bytes (17 MB, 16 MiB) copied, 0.00789041 s, 2.1 GB/s
kallisti5@eris fatr :) $ ls -lah /home/kallisti5/fat12.img
-rw-rw-r-- 1 kallisti5 kallisti5 16M Aug 11 08:04 /home/kallisti5/fat12.img
kallisti5@eris fatr :) $ mkfs.fat -F12 /home/kallisti5/fat12.img
mkfs.fat 4.1 (2017-01-24)
kallisti5@eris fatr :) $ file /home/kallisti5/fat12.img
/home/kallisti5/fat12.img: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID "mkfs.fat", sectors/cluster 16, reserved sectors 16, root entries 512, sectors 32768 (volumes <=32 MB) , Media descriptor 0xf8, sectors/FAT 16, sectors/track 32, heads 64, serial number 0xb6b5b284, unlabeled, FAT (12 bit)
kallisti5@eris fatr :) $ ./target/debug/
build/        deps/         examples/     fatr          .fingerprint/ incremental/  native/
kallisti5@eris fatr :) $ ./target/debug/fatr ls /home/kallisti5/fat12.img
kallisti5@eris fatr :) $ ./target/debug/fatr add /home/kallisti5/error.png /home/kallisti5/fat12.img
error: no free entries

Injecting the file with linux mount, but not showing via fatr ls:

kallisti5@eris fatr :( $ mkdir /tmp/mount
kallisti5@eris fatr :( $ sudo mount /home/kallisti5/fat12.img /tmp/mount
kallisti5@eris fatr :( $ sudo cp ~/error.png /tmp/mount/
kallisti5@eris fatr :) $ sudo umount /tmp/mount
kallisti5@eris fatr :) $ ./target/debug/fatr ls /home/kallisti5/fat12.img
kallisti5@eris fatr :) $

[kallisti5]

Hm, a little troubleshooting:

diff --git a/src/fat/image.rs b/src/fat/image.rs
index 9357cf3..d874fad 100644
--- a/src/fat/image.rs
+++ b/src/fat/image.rs
@@ -75,6 +75,7 @@ impl Image {
 
     // TODO: Make this an iterator
     pub fn root_entries(&self) -> Vec<RootEntry> {
+        println!("root_dir: {:?}", self.root_dir);
         self.root_dir
             .chunks(BYTES_PER_ROOT_ENTRY)
             .map(|chunk| {
@@ -83,10 +84,11 @@ impl Image {
 
                 let entry: RootEntry;
                 unsafe { entry = mem::transmute(entry_bytes); }
+                println!("entry: {:?}", entry);
                 entry
             })
             .filter(|entry| { entry.filename[0] != 0xe5 })
-            .take_while(|entry| { entry.filename[0] != 0 })
+            //.take_while(|entry| { entry.filename[0] != 0 })
             .collect::<Vec<RootEntry>>()
     }

Full data attached.

$ file ~/fat12.img 
/home/kallisti5/fat12.img: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID "mkfs.fat", sectors/cluster 16, reserved sectors 16, root entries 512, sectors 32768 (volumes <=32 MB) , Media descriptor 0xf8, sectors/FAT 16, sectors/track 32, heads 64, serial number 0xa658378, unlabeled, FAT (12 bit)

Looks like:

• Root entries aren't populated in order from 0+
• Root entry offsets incorrect?

logs.txt

[kallisti5]

After using the data from the BIOS Param Block instead of making assumptions on sector sizes, starting to see some life from fatr on fat12 images created under Linux:

kallisti5@nyx fatr :) $ ./target/debug/fatr ls ~/fat12.img 
BIOSParam { bytes_per_sector: 512, sectors_per_cluster: 4, reserved_sectors: 1, fat_count: 2, max_roots: 512, sectors: 8192, media_id: 248, sectors_per_fat: 6 }

HAIKU   .    0
Atest.. 4294967295
TEST    .TXT 7