Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Also avoids confusion with hlen = head->len

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

While readdir is notorious to return DT_UNKNOWN, it works well on btrfs and
devtmpfs, which are two filesystems which are most interesting for us.

It is said it is possible for non-compressed extents, rendering some fields
of the struct garbage.  I couldn't find anything like this on any of my
disks, so let's just check and fail.

Usually they're not mapped at all, but if they are, they have a giant bogus
ram_bytes thus blow the Uncompressed size.

Now this is a brown-paper-bag bug...

A dirty hack; pushing only so I can test other stuff.  My largest 32-bit
machine has 64GB eMMC but many popular NASes use 32-bit ARM or MIPS.

It would be safer to stat() before open(), but is there a way to do so
without a TOCTOU race that's a root hole?  (Not that there'll be many users
on shared systems trying to exploit this particular program...)

Less work to write it anew than to sanitize.

This tends to always get out of sync.

It's never more than "100%" (ie, 3 bytes + '%' + '\0'), but still...

Includes only bytes actually used by a file, but if an extent is reflinked
multiple times, it will be counted every time.  Ie, the size will be what a
traditional filesystem with sparse files and efficient tail packing would
need.

Tests using UBSAN and valgrind make it seem all is ok now.

This reverts commit 760c9e5b.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>

Signed-off-by: Adam Borowski <kilobyte@angband.pl>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>