Behavioral changes:
- A single wildcard ('*') does not cross directory boundary anymore.
Previously 'a*b' would also match 'a/b', but no other tool that I am
aware of matches paths that way. This change breaks compatibility with
old exclude patterns but improves consistency with other tools.
- Patterns with a trailing '/' now prevent recursing into the directory.
Previously any directory excluded with such a pattern would show up as
a regular directory with all its contents excluded, but now the
directory entry itself shows up as excluded.
- If the path given to ncdu matches one of the exclude patterns, the old
implementation would exclude every file/dir being read, this new
implementation would instead ignore the rule. Not quite sure how to
best handle this case, perhaps just exit with an error message?
Performance wise, I haven't yet found a scenario where this
implementation is slower than the old one and it's *significantly*
faster in some cases - in particular when using a large amount of
patterns, especially with literal paths and file names.
That's not to say this implementation is anywhere near optimal:
- A list of relevant patterns is constructed for each directory being
scanned. It may be possible to merge pattern lists that share
the same prefix, which could both reduce memory use and the number of
patterns that need to be matched upon entering a directory.
- A hash table with dynamic arrays as values is just garbage from a
memory allocation point of view.
- This still uses libc fnmatch(), but there's an opportunity to
precompile patterns for faster matching.
And also adjust the graph width calculation to do a better job when the
largest item is smaller than the number of columns used for the graph,
which would previously draw either nothing (if size = 0) or a full bar
(if size > 0).
Fixes#172.
I'm tagging this as a "stable" 2.0 release because the 2.0-beta#
numbering will get confusing when I'm working on new features and fixes.
It's still only usable for people who can use the particular Zig version
that's required (0.9.0 currently) and it will certainly break on
different Zig versions. But once you have a working binary for a
supported arch, it's perfectly stable.
The --enable-* options also work for imported files, this fixes#120.
Most other options are not super useful on its own, but these will be
useful when there's a config file.
While this simplifies the code a bit, it's a regression in the sense
that it increases memory use.
This commit is yak shaving for another hard link counting approach I'd
like to try out, which should be a *LOT* less memory hungry compared to
the current approach. Even though it does, indeed, add an extra cost of
these parent node pointers.
This complicated the scan code more than I had anticipated and has a
few inherent bugs with respect to calculating shared hardlink sizes.
Still, the merge approach avoids creating a full copy of the subtree, so
that's another memory usage related win compared to the C version.
On the other hand, it does leak memory if nodes can't be reused.
Not quite as well tested as I should have, so I'm sure there's bugs.
In a similar way to the C version of ncdu: by wrapping malloc(). It's
simpler to handle allocation failures at the source to allow for easy
retries, pushing the retries up the stack will complicate code somewhat
more. Likewise, this is a best-effort approach to handling OOM,
allocation failures in ncurses aren't handled and display glitches may
occur when we get an OOM inside a drawing function.
This is a somewhat un-Zig-like way of handling errors and adds
scary-looking 'catch unreachable's all over the code, but that's okay.
Performance is looking great, but the code is rather ugly and
potentially buggy. Also doesn't handle hard links without an "nlink"
field yet.
Error handling of the import code is different from what I've been doing
until now. That's intentional, I'll change error handling of other
pieces to call ui.die() directly rather than propagating error enums.
The approach is less testable but conceptually simpler, it's perfectly
fine for a tiny application like ncdu.
I plan to add more display options, but ran out of keys to bind.
Probably going for a quick-select menu thingy so that we can keep the
old key bindings for people accustomed to it.
The graph width algorithm is slightly different, but I think this one's
a minor improvement.
Now we're getting somewhere. This works surprisingly well, too. Existing
ncdu behavior is to remember which entry was previously selected but not
which entry was displayed at the top, so the view would be slightly
different when switching directories. This new approach remembers both
the entry and the offset.
I initially wanted to keep a directory's block count and size as a
separate field so that exporting an in-memory tree to a JSON dump would
be easier to do, but that doesn't seem like a common operation to
optimize for. We'll probably need the algorithms to subtract sub-items
from directory counts anyway, so such an export can still be
implemented, albeit slower.
libc locale-dependent APIs are pure madness, but I can't avoid them as
long as I use ncurses. libtickit seems like a much saner alternative (at
first glance), but no popular application seems to use it. :(
Eaiser to implement now that we're linking against libc.
But exclude pattern matching is extremely slow, so that should really be
rewritten with a custom fnmatch implementation. It's exactly as slow as
in ncdu 1.x as well, I'm surprised nobody's complained about it yet.
And while I'm at it, supporting .gitignore-style patterns would be
pretty neat, too.
I tried playing with zbox (pure Zig termbox-like lib) for a bit, but I
don't think I want to have to deal with the terminal support issues that
will inevitably come with it. I already stumbled upon one myself: it
doesn't properly put the terminal in a sensible state after cleanup in
tmux. As much as I dislike ncurses, it /is/ ubiquitous and tends to kind
of work.
