Version 2.9.2

Works around Zig issue https://github.com/ziglang/zig/issues/25664

Fixes #266

ChangeLog

@@ -1,6 +1,46 @@
 # SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
 # SPDX-License-Identifier: MIT
 
+2.9.2 - 2025-10-24
+	- Still requires Zig 0.14 or 0.15
+	- Fix hang on loading config file when compiled with Zig 0.15.2
+
+2.9.1 - 2025-08-21
+	- Add support for building with Zig 0.15
+	- Zig 0.14 is still supported
+
+2.9 - 2025-08-16
+	- Still requires Zig 0.14
+	- Add --delete-command option to replace the built-in file deletion
+	- Move term cursor to selected option in delete confirmation window
+	- Support binary import on older Linux kernels lacking statx() (may break
+	  again in the future, Zig does not officially support such old kernels)
+
+2.8.2 - 2025-05-01
+	- Still requires Zig 0.14
+	- Fix a build error on MacOS
+
+2.8.1 - 2025-04-28
+	- Still requires Zig 0.14
+	- Fix integer overflow in binary export
+	- Fix crash when `fstatat()` returns EINVAL
+	- Minor build system improvements
+
+2.8 - 2025-03-05
+	- Now requires Zig 0.14
+	- Add support for @-prefixed lines to ignore errors in config file
+	- List all supported options in `--help`
+	- Use `kB` instead of `KB` in `--si` mode
+
+2.7 - 2024-11-19
+	- Still requires Zig 0.12 or 0.13
+	- Support transparent reading/writing of zstandard-compressed JSON
+	- Add `--compress` and `--export-block-size` options
+	- Perform tilde expansion on paths in the config file
+	- Fix JSON import of escaped UTF-16 surrogate pairs
+	- Fix incorrect field in root item when exporting to the binary format
+	- Add -Dstrip build flag
+
 2.6 - 2024-09-27
 	- Still requires Zig 0.12 or 0.13
 	- Add dependency on libzstd

Makefile

@@ -9,7 +9,7 @@ ZIG ?= zig
 PREFIX ?= /usr/local
 BINDIR ?= ${PREFIX}/bin
 MANDIR ?= ${PREFIX}/share/man/man1
-ZIG_FLAGS ?= --release=fast
+ZIG_FLAGS ?= --release=fast -Dstrip
 
 NCDU_VERSION=$(shell grep 'program_version = "' src/main.zig | sed -e 's/^.*"\(.\+\)".*$$/\1/')
 
@@ -68,24 +68,25 @@ static-%.tar.gz:
 		LD="${ZIG} cc --target=$*"\
 		AR="${ZIG} ar" RANLIB="${ZIG} ranlib"
 	cd static-$*/nc && ../../ncurses/configure --prefix="`pwd`/../inst"\
-		--with-pkg-config-libdir="`pwd`/../inst/pkg"\
 		--without-cxx --without-cxx-binding --without-ada --without-manpages --without-progs\
-		--without-tests --enable-pc-files --without-pkg-config --without-shared --without-debug\
+		--without-tests --disable-pc-files --without-pkg-config --without-shared --without-debug\
 		--without-gpm --without-sysmouse --enable-widec --with-default-terminfo-dir=/usr/share/terminfo\
 		--with-terminfo-dirs=/usr/share/terminfo:/lib/terminfo:/usr/local/share/terminfo\
 		--with-fallbacks="screen linux vt100 xterm xterm-256color" --host=$*\
 		CC="${ZIG} cc --target=$*"\
 		LD="${ZIG} cc --target=$*"\
 		AR="${ZIG} ar" RANLIB="${ZIG} ranlib"\
-		CPPFLAGS=-D_GNU_SOURCE && make -j8 && make install.libs
+		CPPFLAGS=-D_GNU_SOURCE && make -j8
 	@# zig-build - cleaner approach but doesn't work, results in a dynamically linked binary.
 	@#cd static-$* && PKG_CONFIG_LIBDIR="`pwd`/inst/pkg" zig build -Dtarget=$*
 	@#	--build-file ../build.zig --search-prefix inst/ --cache-dir zig -Drelease-fast=true
 	@# Alternative approach, bypassing zig-build
 	cd static-$* && ${ZIG} build-exe -target $*\
-		-Iinst/include -Iinst/include/ncursesw -Izstd -lc inst/lib/libncursesw.a zstd/libzstd.a\
+		-Inc/include -Izstd -lc nc/lib/libncursesw.a zstd/libzstd.a\
 		--cache-dir zig-cache -static -fstrip -O ReleaseFast ../src/main.zig
-	strip -R .eh_frame -R .eh_frame_hdr static-$*/main
+	@# My system's strip can't deal with arm binaries and zig doesn't wrap a strip alternative.
+	@# Whatever, just let it error for those.
+	strip -R .eh_frame -R .eh_frame_hdr static-$*/main || true
 	cd static-$* && mv main ncdu && tar -czf ../static-$*.tar.gz ncdu
 	rm -rf static-$*
 

README.md

@@ -19,7 +19,7 @@ C version (1.x).
 
 ## Requirements
 
-- Zig 0.12 or 0.13.
+- Zig 0.14 or 0.15
 - Some sort of POSIX-like OS
 - ncurses
 - libzstd

build.zig

@@ -7,21 +7,26 @@ pub fn build(b: *std.Build) void {
     const target = b.standardTargetOptions(.{});
     const optimize = b.standardOptimizeOption(.{});
 
-    const pie = b.option(bool, "pie", "Build with PIE support (by default false)") orelse false;
+    const pie = b.option(bool, "pie", "Build with PIE support (by default: target-dependant)");
+    const strip = b.option(bool, "strip", "Strip debugging info (by default false)") orelse false;
 
-    const exe = b.addExecutable(.{
+    const main_mod = b.createModule(.{
-        .name = "ncdu",
         .root_source_file = b.path("src/main.zig"),
         .target = target,
         .optimize = optimize,
+        .strip = strip,
         .link_libc = true,
     });
+    main_mod.linkSystemLibrary("ncursesw", .{});
+    main_mod.linkSystemLibrary("zstd", .{});
 
+    const exe = b.addExecutable(.{
+        .name = "ncdu",
+        .root_module = main_mod,
+    });
     exe.pie = pie;
-    exe.root_module.linkSystemLibrary("ncursesw", .{});
+    // https://github.com/ziglang/zig/blob/faccd79ca5debbe22fe168193b8de54393257604/build.zig#L745-L748
-    exe.root_module.linkSystemLibrary("libzstd", .{});
+    if (target.result.os.tag.isDarwin()) {
-    // https://github.com/ziglang/zig/blob/b52be973dfb7d1408218b8e75800a2da3dc69108/build.zig#L551-L554
-    if (target.result.isDarwin()) {
         // useful for package maintainers
         exe.headerpad_max_install_names = true;
     }
@@ -37,13 +42,9 @@ pub fn build(b: *std.Build) void {
     run_step.dependOn(&run_cmd.step);
 
     const unit_tests = b.addTest(.{
-        .root_source_file = b.path("src/main.zig"),
+        .root_module = main_mod,
-        .target = target,
-        .optimize = optimize,
-        .link_libc = true,
     });
     unit_tests.pie = pie;
-    unit_tests.root_module.linkSystemLibrary("ncursesw", .{});
 
     const run_unit_tests = b.addRunArtifact(unit_tests);
 

ncdu.1

@@ -1,6 +1,6 @@
 .\" SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
 .\" SPDX-License-Identifier: MIT
-.Dd September 27, 2024
+.Dd August 16, 2025
 .Dt NCDU 1
 .Os
 .Sh NAME
@@ -21,7 +21,9 @@
 .Op Fl L , \-follow\-symlinks , \-no\-follow\-symlinks
 .Op Fl \-include\-kernfs , \-exclude\-kernfs
 .Op Fl t , \-threads Ar num
+.Op Fl c , \-compress , \-no\-compress
 .Op Fl \-compress\-level Ar num
+.Op Fl \-export\-block\-size Ar num
 .Op Fl 0 , 1 , 2
 .Op Fl q , \-slow\-ui\-updates , \-fast\-ui\-updates
 .Op Fl \-enable\-shell , \-disable\-shell
@@ -42,6 +44,7 @@
 .Op Fl \-group\-directories\-first , \-no\-group\-directories\-first
 .Op Fl \-confirm\-quit , \-no\-confirm\-quit
 .Op Fl \-confirm\-delete , \-no\-confirm\-delete
+.Op Fl \-delete\-command Ar command
 .Op Fl \-color Ar off | dark | dark-bg
 .Op Ar path
 .Nm
@@ -97,6 +100,11 @@ uncompressed, or a little over 100 KiB when compressed with gzip.
 This scales linearly, so be prepared to handle a few tens of megabytes when
 dealing with millions of files.
 .Pp
+Consider enabling
+.Fl c
+to output Zstandard-compressed JSON, which can significantly reduce size of the
+exported data.
+.Pp
 When running a multi-threaded scan or when scanning a directory tree that may
 not fit in memory, consider using
 .Fl O
@@ -187,12 +195,36 @@ The binary format (see
 .Fl O )
 does not have this problem and supports efficient exporting with any number of
 threads.
+.El
+.
+.Ss Export Options
+These options affect behavior when exporting to file with the
+.Fl o
+or
+.Fl O
+options.
+.Bl -tag -width Ds
+.It Fl c , \-compress , \-no\-compress
+Enable or disable Zstandard compression when exporting to JSON (see
+.Fl o ) .
 .It Fl \-compress\-level Ar num
 Set the Zstandard compression level when using
 .Fl O
-to create a binary export.
+or
+.Fl c .
 Valid values are 1 (fastest) to 19 (slowest).
 Defaults to 4.
+.It Fl \-export\-block\-size Ar num
+Set the block size, in kibibytes, for the binary export format (see
+.Fl O ) .
+Larger blocks require more memory but result in better compression efficiency.
+This option can be combined with a higher
+.Fl \-compress\-level
+for even better compression.
+.Pp
+Accepted values are between 4 and 16000.
+The defaults is to start at 64 KiB and then gradually increase the block size
+for large exports.
 .El
 .
 .Ss Interface Options
@@ -255,7 +287,7 @@ when given twice it will also add
 thus ensuring that there is no way to modify the file system from within
 .Nm .
 .It Fl \-si , \-no\-si
-List sizes using base 10 prefixes, that is, powers of 1000 (KB, MB, etc), as
+List sizes using base 10 prefixes, that is, powers of 1000 (kB, MB, etc), as
 defined in the International System of Units (SI), instead of the usual base 2
 prefixes (KiB, MiB, etc).
 .It Fl \-disk\-usage , \-apparent\-size
@@ -328,6 +360,31 @@ Can be helpful when you accidentally press 'q' during or after a very long scan.
 Require a confirmation before deleting a file or directory.
 Enabled by default, but can be disabled if you're absolutely sure you won't
 accidentally press 'd'.
+.It Fl \-delete\-command Ar command
+When set to a non-empty string, replace the built-in file deletion feature with
+a custom shell command.
+.Pp
+The absolute path of the item to be deleted is appended to the given command
+and the result is evaluated in a shell.
+The command is run from the same directory that ncdu itself was started in.
+The
+.Ev NCDU_DELETE_PATH
+environment variable is set to the absolute path of the item to be deleted and
+.Ev NCDU_LEVEL
+is set in the same fashion as when spawning a shell from within ncdu.
+.Pp
+After command completion, the in-memory view of the selected item is refreshed
+and directory sizes are adjusted as necessary.
+This is not a full refresh of the complete directory tree, so if the item has
+been renamed or moved to another directory, it's new location is not
+automatically picked up.
+.Pp
+For example, to use
+.Xr rm 1
+interactive mode to prompt before each deletion:
+.Dl ncdu --no-confirm-delete --delete-command \[aq]rm -ri --\[aq]
+Or to move files to trash:
+.Dl ncdu --delete-command \[aq]gio trash --\[aq]
 .It Fl \-color Ar off | dark | dark-bg
 Set the color scheme.
 The following schemes are recognized:
@@ -361,6 +418,7 @@ is given on the command line.
 .Pp
 The configuration file format is simply one command line option per line.
 Lines starting with '#' are ignored.
+A line can be prefixed with '@' to suppress errors while parsing the option.
 Example configuration file:
 .Bd -literal -offset indent
 # Always enable extended mode
@@ -371,6 +429,9 @@ Example configuration file:
 
 # Exclude .git directories
 \-\-exclude .git
+
+# Read excludes from ~/.ncduexcludes, ignore error if the file does not exist
+@--exclude-from ~/.ncduexcludes
 .Ed
 .
 .Sh KEYS
@@ -487,34 +548,28 @@ Empty directory.
 .Sh EXAMPLES
 To scan and browse the directory you're currently in, all you need is a simple:
 .Dl ncdu
-If you want to scan a full filesystem, for example your root filesystem, then
+To scan a full filesystem, for example your root filesystem, you'll want to use
-you'll want to use
 .Fl x :
 .Dl ncdu \-x /
 .Pp
 Since scanning a large directory may take a while, you can scan a directory and
 export the results for later viewing:
 .Bd -literal -offset indent
-ncdu \-1xo\- / | gzip >export.gz
+ncdu \-1xO export.ncdu /
 # ...some time later:
-zcat export.gz | ncdu \-f\-
+ncdu \-f export.ncdu
 .Ed
 To export from a cron job, make sure to replace
 .Fl 1
 with
 .Fl 0
-to suppress any unnecessary output.
+to suppress unnecessary progress output.
 .Pp
 You can also export a directory and browse it once scanning is done:
-.Dl ncdu \-o\- | tee export.file | ./ncdu \-f\-
+.Dl ncdu \-co\- | tee export.json.zst | ./ncdu \-f\-
-The same is possible with gzip compression, but is a bit kludgey:
-.Dl ncdu \-o\- | gzip | tee export.gz | gunzip | ./ncdu \-f\-
 .Pp
 To scan a system remotely, but browse through the files locally:
-.Dl ssh \-C user@system ncdu \-o\- / | ./ncdu \-f\-
+.Dl ssh user@system ncdu \-co\- / | ./ncdu \-f\-
-The
-.Fl C
-option to ssh enables compression, which will be very useful over slow links.
 Remote scanning and local viewing has two major advantages when
 compared to running
 .Nm

ncdubinexp.pl

@@ -1,242 +0,0 @@
-#!/usr/bin/perl
-# SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
-# SPDX-License-Identifier: MIT
-
-
-# Usage: ncdubinexp.pl [options] <export.ncdu
-# Or: ncdu -O- | ncdubinexp.pl [options]
-#
-# Reads and validates a binary ncdu export file and optionally prints out
-# various diagnostic data and statistics.
-#
-# Options:
-#   blocks    - print a listing of all blocks as they are read
-#   items     - print a listing of all items as they are read
-#   dirs      - print out dir listing stats
-#   stats     - print some overview stats
-#
-# This script is highly inefficient in both RAM and CPU, not suitable for large
-# exports.
-# This script does not permit unknown blocks or item keys, although that is
-# technically valid.
-
-
-use v5.36;
-use autodie;
-use bytes;
-no warnings 'portable';
-use List::Util 'min', 'max';
-use CBOR::XS;  # Does not officially support recent perl versions, but it's the only CPAN module that supports streaming.
-use Compress::Zstd;
-
-my $printblocks = grep $_ eq 'blocks', @ARGV;
-my $printitems = grep $_ eq 'items', @ARGV;
-my $printdirs = grep $_ eq 'dirs', @ARGV;
-my $printstats = grep $_ eq 'stats', @ARGV;
-
-my %datablocks;
-my %items;
-my $root_itemref;
-my $datablock_len = 0;
-my $rawdata_len = 0;
-my $minitemsperblock = 1e10;
-my $maxitemsperblock = 0;
-
-{
-    die "Input too short\n" if 8 != read STDIN, my $sig, 8;
-    die "Invalid file signature\n" if $sig ne "\xbfncduEX1";
-}
-
-my @itemkeys = qw/
-    type
-    name
-    prev
-    asize
-    dsize
-    dev
-    rderr
-    cumasize
-    cumdsize
-    shrasize
-    shrdsize
-    items
-    sub
-    ino
-    nlink
-    uid
-    gid
-    mode
-    mtime
-/;
-
-
-sub datablock($prefix, $off, $blklen, $content) {
-    die "$prefix: Data block too small\n" if length $content < 8;
-    die "$prefix: Data block too large\n" if length $content >= (1<<24);
-
-    my $num = unpack 'N', $content;
-    die sprintf "%s: Duplicate block id %d (first at %010x)", $prefix, $num, $datablocks{$num}>>24 if $datablocks{$num};
-    $datablocks{$num} = ($off << 24) | $blklen;
-
-    my $compressed = substr $content, 4;
-    my $rawdata = decompress($compressed);
-    die "$prefix: Block id $num failed decompression\n" if !defined $rawdata;
-    die "$prefix: Uncompressed data block size too large\n" if length $rawdata >= (1<<24);
-
-    $printblocks && printf "%s: data block %d  rawlen %d (%.2f)\n", $prefix, $num, length($rawdata), length($compressed)/length($rawdata)*100;
-
-    $datablock_len += length($compressed);
-    $rawdata_len += length($rawdata);
-
-    cbordata($num, $rawdata);
-}
-
-
-sub fmtitem($val) {
-    join '  ', map "$_:$val->{$_}", grep exists $val->{$_}, @itemkeys;
-}
-
-
-sub cbordata($blknum, $data) {
-    my $cbor = CBOR::XS->new_safe;
-    my $off = 0;
-    my $nitems = 0;
-    while ($off < length $data) { # This substr madness is prolly quite slow
-        my($val, $len) = $cbor->decode_prefix(substr $data, $off);
-        my $itemref = ($blknum << 24) | $off;
-        $off += $len;
-        $nitems++;
-
-        # Basic validation of the CBOR data. Doesn't validate that every value
-        # has the correct CBOR type or that integers are within range.
-        $val = { _itemref => $itemref, map {
-            die sprintf "#%010x: Invalid CBOR key '%s'\n", $itemref, $_ if !/^[0-9]+$/ || !$itemkeys[$_];
-            my($k, $v) = ($itemkeys[$_], $val->{$_});
-            die sprintf "#%010x: Invalid value for key '%s': '%s'\n", $itemref, $k, $v
-                if ref $v eq 'ARRAY' || ref $v eq 'HASH' || !defined $v || !(
-                    $k eq 'type' ? ($v =~ /^(-[1-4]|[0-3])$/) :
-                    $k eq 'prev' || $k eq 'sub' || $k eq 'prevlnk' ? 1 : # itemrefs are validated separately
-                    $k eq 'name' ? length $v :
-                    $k eq 'rderr' ? Types::Serialiser::is_bool($v) :
-                    /^[0-9]+$/
-                );
-            ($k,$v)
-        } keys %$val };
-
-        $printitems && printf "#%010x: %s\n", $itemref, fmtitem $val;
-        $items{$itemref} = $val;
-    }
-    $minitemsperblock = $nitems if $minitemsperblock > $nitems;
-    $maxitemsperblock = $nitems if $maxitemsperblock < $nitems;
-}
-
-
-sub indexblock($prefix, $content) {
-    $printblocks && print "$prefix: index block\n";
-
-    my $maxnum = max keys %datablocks;
-    die "$prefix: index block size incorrect for $maxnum+1 data blocks\n" if length($content) != 8*($maxnum+1) + 8;
-
-    my @ints = unpack 'Q>*', $content;
-    $root_itemref = pop @ints;
-
-    for my $i (0..$#ints-1) {
-        if (!$datablocks{$i}) {
-            die "$prefix: index entry for missing block (#$i) must be 0\n" if $ints[$i] != 0;
-        } else {
-            die sprintf "%s: invalid index entry for block #%d (got %016x expected %016x)\n",
-                $prefix, $i, $ints[$i], $datablocks{$i}
-                if $ints[$i] != $datablocks{$i};
-        }
-    }
-}
-
-
-while (1) {
-    my $off = tell STDIN;
-    my $prefix = sprintf '%010x', $off;
-    die "$prefix Input too short, expected block header\n" if 4 != read STDIN, my $blkhead, 4;
-    $blkhead = unpack 'N', $blkhead;
-    my $blkid = $blkhead >> 28;
-    my $blklen = $blkhead & 0x0fffffff;
-
-    $prefix .= "[$blklen]";
-    die "$prefix: Short read on block content\n" if $blklen - 8 != read STDIN, my $content, $blklen - 8;
-    die "$prefix: Input too short, expected block footer\n" if 4 != read STDIN, my $blkfoot, 4;
-    die "$prefix: Block footer does not match header\n" if $blkhead != unpack 'N', $blkfoot;
-
-    if ($blkid == 0) {
-        datablock($prefix, $off, $blklen, $content);
-    } elsif ($blkid == 1) {
-        indexblock($prefix, $content);
-        last;
-    } else {
-        die "$prefix Unknown block id $blkid\n";
-    }
-}
-
-{
-    die sprintf "0x%08x: Data after index block\n", tell(STDIN) if 0 != read STDIN, my $x, 1;
-}
-
-
-
-# Each item must be referenced exactly once from either a 'prev' or 'sub' key,
-# $nodup verifies the "at most once" part.
-sub resolve($cur, $key, $nodup) {
-    my $ref = exists $cur->{$key} ? $cur->{$key} : return;
-    my $item = $ref < 0
-        ? ($items{ $cur->{_itemref} + $ref } || die sprintf "#%010x: Invalid relative itemref %s: %d\n", $cur->{_itemref}, $key, $ref)
-        : ($items{$ref} || die sprintf "#%010x: Invalid reference %s to #%010x\n", $cur->{_itemref}, $key, $ref);
-    die sprintf "Item #%010x referenced more than once, from #%010x and #%010x\n", $item->{_itemref}, $item->{_lastseen}, $cur->{_itemref}
-        if $nodup && defined $item->{_lastseen};
-    $item->{_lastseen} = $cur->{_itemref} if $nodup;
-    return $item;
-}
-
-my @dirblocks; # [ path, nitems, nblocks ]
-my %dirblocks; # nblocks => ndirs
-
-sub traverse($parent, $path) {
-    my $sub = resolve($parent, 'sub', 1);
-    my %blocks;
-    my $items = 0;
-    while ($sub) {
-        $items++;
-        $blocks{ $sub->{_itemref} >> 24 }++;
-        traverse($sub, "$path/$sub->{name}") if $sub->{type} == 0;
-        $sub = resolve($sub, 'prev', 1);
-    }
-    push @dirblocks, [ $path, $items, scalar keys %blocks ] if scalar keys %blocks > 1;
-    $dirblocks{ keys %blocks }++ if $items > 0;
-    $items && $printdirs && printf "#%010x: %d items in %d blocks (%d .. %d)  %s\n",
-        $parent->{_itemref}, $items, scalar keys %blocks,
-        min(values %blocks), max(values %blocks), $path;
-}
-
-
-{
-    my $root = $items{$root_itemref} || die sprintf "Invalid root itemref: %010x\n", $root_itemref;
-    $root->{_lastseen} = 0xffffffffff;
-    traverse($root, $root->{name});
-
-    my($noref) = grep !$_->{_lastseen}, values %items;
-    die sprintf "No reference found to #%010x\n", $noref->{_itemref} if $noref;
-}
-
-if ($printstats) {
-    my $nblocks = keys %datablocks;
-    my $nitems = keys %items;
-    printf "     Total items: %d\n", $nitems;
-    printf "    Total blocks: %d\n", $nblocks;
-    printf " Items per block: %.1f (%d .. %d)\n", $nitems / $nblocks, $minitemsperblock, $maxitemsperblock;
-    printf "  Avg block size: %d compressed, %d raw (%.1f)\n", $datablock_len/$nblocks, $rawdata_len/$nblocks, $datablock_len/$rawdata_len*100;
-    printf "   Avg item size: %.1f compressed, %.1f raw\n", $datablock_len/$nitems, $rawdata_len/$nitems;
-
-    @dirblocks = sort { $b->[2] <=> $a->[2] } @dirblocks;
-    print "\nBlocks per directory listing histogram\n";
-    printf "  %5d %6d\n", $_, $dirblocks{$_} for sort { $a <=> $b } keys %dirblocks;
-    print "\nMost blocks per directory listing\n";
-    print "     items blks  path\n";
-    printf "%10d %4d  %s\n", @{$dirblocks[$_]}[1,2,0] for (0..min 9, $#dirblocks);
-}

src/bin_export.zig

@@ -7,20 +7,16 @@ const model = @import("model.zig");
 const sink = @import("sink.zig");
 const util = @import("util.zig");
 const ui = @import("ui.zig");
-
+const c = @import("c.zig").c;
-extern fn ZSTD_compress(dst: ?*anyopaque, dstCapacity: usize, src: ?*const anyopaque, srcSize: usize, compressionLevel: c_int) usize;
-extern fn ZSTD_isError(code: usize) c_uint;
 
 pub const global = struct {
     var fd: std.fs.File = undefined;
-    var index = std.ArrayList(u8).init(main.allocator);
+    var index: std.ArrayListUnmanaged(u8) = .empty;
     var file_off: u64 = 0;
     var lock: std.Thread.Mutex = .{};
     var root_itemref: u64 = 0;
 };
 
-const BLOCK_SIZE: usize = 64*1024;
-
 pub const SIGNATURE = "\xbfncduEX1";
 
 pub const ItemKey = enum(u5) {
@@ -53,7 +49,7 @@ pub const ItemKey = enum(u5) {
 
 // Pessimistic upper bound on the encoded size of an item, excluding the name field.
 // 2 bytes for map start/end, 11 per field (2 for the key, 9 for a full u64).
-const MAX_ITEM_LEN = 2 + 11 * @typeInfo(ItemKey).Enum.fields.len;
+const MAX_ITEM_LEN = 2 + 11 * @typeInfo(ItemKey).@"enum".fields.len;
 
 pub const CborMajor = enum(u3) { pos, neg, bytes, text, array, map, tag, simple };
 
@@ -65,9 +61,6 @@ inline fn blockHeader(id: u4, len: u28) [4]u8 { return bigu32((@as(u32, id) << 2
 
 inline fn cborByte(major: CborMajor, arg: u5) u8 { return (@as(u8, @intFromEnum(major)) << 5) | arg; }
 
-// ZSTD_COMPRESSBOUND(), assuming input does not exceed ZSTD_MAX_INPUT_SIZE
-fn compressBound(size: usize) usize { return size + (size>>8) + (if (size < (128<<10)) ((128<<10) - size) >> 11 else 0); }
-
 
 // (Uncompressed) data block size.
 // Start with 64k, then use increasingly larger block sizes as the export file
@@ -77,7 +70,8 @@ fn compressBound(size: usize) usize { return size + (size>>8) + (if (size < (128
 fn blockSize(num: u32) usize {
     //                        block size    uncompressed data in this num range
     //                 # mil      # KiB         # GiB
-    return if (num < ( 1<<20))   64<<10  //    64
+    return main.config.export_block_size
+    orelse if (num < ( 1<<20))   64<<10  //    64
       else if (num < ( 2<<20))  128<<10  //   128
       else if (num < ( 4<<20))  256<<10  //   512
       else if (num < ( 8<<20))  512<<10  //  2048
@@ -85,10 +79,15 @@ fn blockSize(num: u32) usize {
       else                     2048<<10; // 32768
 }
 
+// Upper bound on the return value of blockSize()
+// (config.export_block_size may be larger than the sizes listed above, let's
+// stick with the maximum block size supported by the file format to be safe)
+const MAX_BLOCK_SIZE: usize = 1<<28;
+
 
 pub const Thread = struct {
     buf: []u8 = undefined,
-    off: usize = std.math.maxInt(usize) - (1<<10), // large number to trigger a flush() for the first write
+    off: usize = MAX_BLOCK_SIZE, // pretend we have a full block to trigger a flush() for the first write
     block_num: u32 = std.math.maxInt(u32),
     itemref: u64 = 0, // ref of item currently being written
 
@@ -100,17 +99,17 @@ pub const Thread = struct {
 
     fn compressZstd(in: []const u8, out: []u8) usize {
         while (true) {
-            const r = ZSTD_compress(out.ptr, out.len, in.ptr, in.len, main.config.complevel);
+            const r = c.ZSTD_compress(out.ptr, out.len, in.ptr, in.len, main.config.complevel);
-            if (ZSTD_isError(r) == 0) return r;
+            if (c.ZSTD_isError(r) == 0) return r;
             ui.oom(); // That *ought* to be the only reason the above call can fail.
         }
     }
 
-    fn createBlock(t: *Thread) std.ArrayList(u8) {
+    fn createBlock(t: *Thread) std.ArrayListUnmanaged(u8) {
-        var out = std.ArrayList(u8).init(main.allocator);
+        var out: std.ArrayListUnmanaged(u8) = .empty;
         if (t.block_num == std.math.maxInt(u32) or t.off == 0) return out;
 
-        out.ensureTotalCapacityPrecise(12 + compressBound(t.off)) catch unreachable;
+        out.ensureTotalCapacityPrecise(main.allocator, 12 + @as(usize, @intCast(c.ZSTD_COMPRESSBOUND(@as(c_int, @intCast(t.off)))))) catch unreachable;
         out.items.len = out.capacity;
         const bodylen = compressZstd(t.buf[0..t.off], out.items[8..]);
         out.items.len = 12 + bodylen;
@@ -122,13 +121,13 @@ pub const Thread = struct {
     }
 
     fn flush(t: *Thread, expected_len: usize) void {
-        @setCold(true);
+        @branchHint(.unlikely);
-        const block = createBlock(t);
+        var block = createBlock(t);
-        defer block.deinit();
+        defer block.deinit(main.allocator);
 
         global.lock.lock();
         defer global.lock.unlock();
-        // This can only really happen when the root path exceeds BLOCK_SIZE,
+        // This can only really happen when the root path exceeds our block size,
         // in which case we would probably have error'ed out earlier anyway.
         if (expected_len > t.buf.len) ui.die("Error writing data: path too long.\n", .{});
 
@@ -142,7 +141,7 @@ pub const Thread = struct {
 
         t.off = 0;
         t.block_num = @intCast((global.index.items.len - 4) / 8);
-        global.index.appendSlice(&[1]u8{0}**8) catch unreachable;
+        global.index.appendSlice(main.allocator, &[1]u8{0}**8) catch unreachable;
         if (global.index.items.len + 12 >= (1<<28)) ui.die("Too many data blocks, please report a bug.\n", .{});
 
         const newsize = blockSize(t.block_num);
@@ -395,7 +394,7 @@ pub const Dir = struct {
             p.last_sub = t.itemStart(.dir, p.last_sub, name);
         } else {
             d.countLinks(null);
-            global.root_itemref = t.itemStart(.dir, 0, name);
+            global.root_itemref = t.itemStart(.dir, null, name);
         }
         d.inodes.deinit();
 
@@ -434,7 +433,7 @@ pub const Dir = struct {
 
 pub fn createRoot(stat: *const sink.Stat, threads: []sink.Thread) Dir {
     for (threads) |*t| {
-        t.sink.bin.buf = main.allocator.alloc(u8, BLOCK_SIZE) catch unreachable;
+        t.sink.bin.buf = main.allocator.alloc(u8, blockSize(0)) catch unreachable;
     }
 
     return .{ .stat = stat.* };
@@ -448,12 +447,12 @@ pub fn done(threads: []sink.Thread) void {
 
     while (std.mem.endsWith(u8, global.index.items, &[1]u8{0}**8))
         global.index.shrinkRetainingCapacity(global.index.items.len - 8);
-    global.index.appendSlice(&bigu64(global.root_itemref)) catch unreachable;
+    global.index.appendSlice(main.allocator, &bigu64(global.root_itemref)) catch unreachable;
-    global.index.appendSlice(&blockHeader(1, @intCast(global.index.items.len + 4))) catch unreachable;
+    global.index.appendSlice(main.allocator, &blockHeader(1, @intCast(global.index.items.len + 4))) catch unreachable;
     global.index.items[0..4].* = blockHeader(1, @intCast(global.index.items.len));
     global.fd.writeAll(global.index.items) catch |e|
         ui.die("Error writing to file: {s}.\n", .{ ui.errorString(e) });
-    global.index.clearAndFree();
+    global.index.clearAndFree(main.allocator);
 
     global.fd.close();
 }
@@ -465,5 +464,5 @@ pub fn setupOutput(fd: std.fs.File) void {
     global.file_off = 8;
 
     // Placeholder for the index block header.
-    global.index.appendSlice("aaaa") catch unreachable;
+    global.index.appendSlice(main.allocator, "aaaa") catch unreachable;
 }

src/bin_reader.zig

@@ -8,9 +8,7 @@ const util = @import("util.zig");
 const sink = @import("sink.zig");
 const ui = @import("ui.zig");
 const bin_export = @import("bin_export.zig");
-
+const c = @import("c.zig").c;
-extern fn ZSTD_decompress(dst: ?*anyopaque, dstCapacity: usize, src: ?*const anyopaque, compressedSize: usize) usize;
-extern fn ZSTD_getFrameContentSize(src: ?*const anyopaque, srcSize: usize) c_ulonglong;
 
 
 const CborMajor = bin_export.CborMajor;
@@ -65,7 +63,7 @@ inline fn bigu32(v: [4]u8) u32 { return std.mem.bigToNative(u32, @bitCast(v)); }
 inline fn bigu64(v: [8]u8) u64 { return std.mem.bigToNative(u64, @bitCast(v)); }
 
 fn die() noreturn {
-    @setCold(true);
+    @branchHint(.cold);
     if (global.lastitem) |e| ui.die("Error reading item {x} from file\n", .{e})
     else ui.die("Error reading from file\n", .{});
 }
@@ -103,11 +101,11 @@ fn readBlock(num: u32) []const u8 {
         catch |e| ui.die("Error reading from file: {s}\n", .{ui.errorString(e)});
     if (rdlen != buf.len) die();
 
-    const rawlen = ZSTD_getFrameContentSize(buf.ptr, buf.len);
+    const rawlen = c.ZSTD_getFrameContentSize(buf.ptr, buf.len);
     if (rawlen <= 0 or rawlen >= (1<<24)) die();
     block.data = main.allocator.alloc(u8, @intCast(rawlen)) catch unreachable;
 
-    const res = ZSTD_decompress(block.data.ptr, block.data.len, buf.ptr, buf.len);
+    const res = c.ZSTD_decompress(block.data.ptr, block.data.len, buf.ptr, buf.len);
     if (res != block.data.len) ui.die("Error decompressing block {} (expected {} got {})\n", .{ num, block.data.len, res });
 
     return block.data;
@@ -340,7 +338,7 @@ const ItemParser = struct {
     // Skips over any fields that don't fit into an ItemKey.
     fn next(r: *ItemParser) ?Field {
         while (r.key()) |k| {
-            if (k.major == .pos and k.arg <= std.math.maxInt(@typeInfo(ItemKey).Enum.tag_type)) return .{
+            if (k.major == .pos and k.arg <= std.math.maxInt(@typeInfo(ItemKey).@"enum".tag_type)) return .{
                 .key = @enumFromInt(k.arg),
                 .val = r.r.next(),
             } else {
@@ -506,7 +504,9 @@ pub fn import() void {
 pub fn open(fd: std.fs.File) !void {
     global.fd = fd;
 
-    const size = try fd.getEndPos();
+    // Do not use fd.getEndPos() because that requires newer kernels supporting statx() #261.
+    try fd.seekFromEnd(0);
+    const size = try fd.getPos();
     if (size < 16) return error.EndOfStream;
 
     // Read index block

src/browser.zig

@@ -9,22 +9,22 @@ const mem_sink = @import("mem_sink.zig");
 const bin_reader = @import("bin_reader.zig");
 const delete = @import("delete.zig");
 const ui = @import("ui.zig");
-const c = @cImport(@cInclude("time.h"));
+const c = @import("c.zig").c;
 const util = @import("util.zig");
 
 // Currently opened directory.
 pub var dir_parent: *model.Dir = undefined;
 pub var dir_path: [:0]u8 = undefined;
-var dir_parents = std.ArrayList(model.Ref).init(main.allocator);
+var dir_parents: std.ArrayListUnmanaged(model.Ref) = .empty;
 var dir_alloc = std.heap.ArenaAllocator.init(main.allocator);
 
 // Used to keep track of which dir is which ref, so we can enter it.
 // Only used for binreader browsing.
-var dir_refs = std.ArrayList(struct { ptr: *model.Dir, ref: u64 }).init(main.allocator);
+var dir_refs: std.ArrayListUnmanaged(struct { ptr: *model.Dir, ref: u64 }) = .empty;
 
 // Sorted list of all items in the currently opened directory.
 // (first item may be null to indicate the "parent directory" item)
-var dir_items = std.ArrayList(?*model.Entry).init(main.allocator);
+var dir_items: std.ArrayListUnmanaged(?*model.Entry) = .empty;
 
 var dir_max_blocks: u64 = 0;
 var dir_max_size: u64 = 0;
@@ -146,7 +146,7 @@ pub fn loadDir(next_sel: u64) void {
     dir_has_shared = false;
 
     if (dir_parents.items.len > 1)
-        dir_items.append(null) catch unreachable;
+        dir_items.append(main.allocator, null) catch unreachable;
     var ref = dir_parent.sub;
     while (!ref.isNull()) {
         const e =
@@ -164,10 +164,10 @@ pub fn loadDir(next_sel: u64) void {
             break :blk !excl and name[0] != '.' and name[name.len-1] != '~';
         };
         if (shown) {
-            dir_items.append(e) catch unreachable;
+            dir_items.append(main.allocator, e) catch unreachable;
             if (e.dir()) |d| {
                 if (d.shared_blocks > 0 or d.shared_size > 0) dir_has_shared = true;
-                if (main.config.binreader) dir_refs.append(.{ .ptr = d, .ref = ref.ref }) catch unreachable;
+                if (main.config.binreader) dir_refs.append(main.allocator, .{ .ptr = d, .ref = ref.ref }) catch unreachable;
             }
         }
 
@@ -185,10 +185,10 @@ pub fn initRoot() void {
     if (main.config.binreader) {
         const ref = bin_reader.getRoot();
         dir_parent = bin_reader.get(ref, main.allocator).dir() orelse ui.die("Invalid import\n", .{});
-        dir_parents.append(.{ .ref = ref }) catch unreachable;
+        dir_parents.append(main.allocator, .{ .ref = ref }) catch unreachable;
     } else {
         dir_parent = model.root;
-        dir_parents.append(.{ .ptr = &dir_parent.entry }) catch unreachable;
+        dir_parents.append(main.allocator, .{ .ptr = &dir_parent.entry }) catch unreachable;
     }
     dir_path = main.allocator.dupeZ(u8, dir_parent.entry.name()) catch unreachable;
     loadDir(0);
@@ -202,10 +202,10 @@ fn enterSub(e: *model.Dir) void {
         };
         dir_parent.entry.destroy(main.allocator);
         dir_parent = bin_reader.get(ref, main.allocator).dir() orelse unreachable;
-        dir_parents.append(.{ .ref = ref }) catch unreachable;
+        dir_parents.append(main.allocator, .{ .ref = ref }) catch unreachable;
     } else {
         dir_parent = e;
-        dir_parents.append(.{ .ptr = &e.entry }) catch unreachable;
+        dir_parents.append(main.allocator, .{ .ptr = &e.entry }) catch unreachable;
     }
 
     const newpath = std.fs.path.joinZ(main.allocator, &[_][]const u8{ dir_path, e.entry.name() }) catch unreachable;
@@ -430,7 +430,7 @@ const info = struct {
 
     var tab: Tab = .info;
     var entry: ?*model.Entry = null;
-    var links: ?std.ArrayList(*model.Link) = null;
+    var links: ?std.ArrayListUnmanaged(*model.Link) = null;
     var links_top: usize = 0;
     var links_idx: usize = 0;
 
@@ -445,7 +445,7 @@ const info = struct {
     // Set the displayed entry to the currently selected item and open the tab.
     fn set(e: ?*model.Entry, t: Tab) void {
         if (e != entry) {
-            if (links) |*l| l.deinit();
+            if (links) |*l| l.deinit(main.allocator);
             links = null;
             links_top = 0;
             links_idx = 0;
@@ -458,10 +458,10 @@ const info = struct {
         state = .info;
         tab = t;
         if (tab == .links and links == null and !main.config.binreader) {
-            var list = std.ArrayList(*model.Link).init(main.allocator);
+            var list: std.ArrayListUnmanaged(*model.Link) = .empty;
             var l = e.?.link().?;
             while (true) {
-                list.append(l) catch unreachable;
+                list.append(main.allocator, l) catch unreachable;
                 l = l.next;
                 if (&l.entry == e)
                     break;
@@ -644,8 +644,8 @@ const info = struct {
     fn keyInput(ch: i32) bool {
         if (entry.?.pack.etype == .link) {
             switch (ch) {
-                '1', 'h', ui.c.KEY_LEFT => { set(entry, .info); return true; },
+                '1', 'h', c.KEY_LEFT => { set(entry, .info); return true; },
-                '2', 'l', ui.c.KEY_RIGHT => { set(entry, .links); return true; },
+                '2', 'l', c.KEY_RIGHT => { set(entry, .links); return true; },
                 else => {},
             }
         }
@@ -802,9 +802,9 @@ const help = struct {
             '1' => tab = .keys,
             '2' => tab = .flags,
             '3' => tab = .about,
-            'h', ui.c.KEY_LEFT => tab = if (tab == .about) .flags else .keys,
+            'h', c.KEY_LEFT => tab = if (tab == .about) .flags else .keys,
-            'l', ui.c.KEY_RIGHT => tab = if (tab == .keys) .flags else .about,
+            'l', c.KEY_RIGHT => tab = if (tab == .keys) .flags else .about,
-            'j', ' ', ui.c.KEY_DOWN, ui.c.KEY_NPAGE => {
+            'j', ' ', c.KEY_DOWN, c.KEY_NPAGE => {
                 const max = switch (tab) {
                     .keys => keys.len/2 - keylines,
                     else => @as(u32, 0),
@@ -812,7 +812,7 @@ const help = struct {
                 if (offset < max)
                     offset += 1;
             },
-            'k', ui.c.KEY_UP, ui.c.KEY_PPAGE => { if (offset > 0) offset -= 1; },
+            'k', c.KEY_UP, c.KEY_PPAGE => { if (offset > 0) offset -= 1; },
             else => state = .main,
         }
     }
@@ -917,16 +917,16 @@ fn sortToggle(col: main.config.SortCol, default_order: main.config.SortOrder) vo
 
 fn keyInputSelection(ch: i32, idx: *usize, len: usize, page: u32) bool {
     switch (ch) {
-        'j', ui.c.KEY_DOWN => {
+        'j', c.KEY_DOWN => {
             if (idx.*+1 < len) idx.* += 1;
         },
-        'k', ui.c.KEY_UP => {
+        'k', c.KEY_UP => {
             if (idx.* > 0) idx.* -= 1;
         },
-        ui.c.KEY_HOME => idx.* = 0,
+        c.KEY_HOME => idx.* = 0,
-        ui.c.KEY_END, ui.c.KEY_LL => idx.* = len -| 1,
+        c.KEY_END, c.KEY_LL => idx.* = len -| 1,
-        ui.c.KEY_PPAGE => idx.* = idx.* -| page,
+        c.KEY_PPAGE => idx.* = idx.* -| page,
-        ui.c.KEY_NPAGE => idx.* = @min(len -| 1, idx.* + page),
+        c.KEY_NPAGE => idx.* = @min(len -| 1, idx.* + page),
         else => return false,
     }
     return true;
@@ -1017,7 +1017,7 @@ pub fn keyInput(ch: i32) void {
         },
 
         // Navigation
-        10, 'l', ui.c.KEY_RIGHT => {
+        10, 'l', c.KEY_RIGHT => {
             if (dir_items.items.len == 0) {
             } else if (dir_items.items[cursor_idx]) |e| {
                 if (e.dir()) |d| {
@@ -1032,7 +1032,7 @@ pub fn keyInput(ch: i32) void {
                 state = .main;
             }
         },
-        'h', '<', ui.c.KEY_BACKSPACE, ui.c.KEY_LEFT => {
+        'h', '<', c.KEY_BACKSPACE, c.KEY_LEFT => {
             if (dir_parents.items.len > 1) {
                 //const h = dir_parent.entry.nameHash();
                 enterParent();

src/c.zig

@@ -0,0 +1,20 @@
+// SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
+// SPDX-License-Identifier: MIT
+
+pub const c = @cImport({
+    @cDefine("_XOPEN_SOURCE", "1"); // for wcwidth()
+    @cInclude("stdio.h"); // fopen(), used to initialize ncurses
+    @cInclude("string.h"); // strerror()
+    @cInclude("time.h"); // strftime()
+    @cInclude("wchar.h"); // wcwidth()
+    @cInclude("locale.h"); // setlocale() and localeconv()
+    @cInclude("fnmatch.h"); // fnmatch()
+    @cInclude("unistd.h"); // getuid()
+    @cInclude("sys/types.h"); // struct passwd
+    @cInclude("pwd.h"); // getpwnam(), getpwuid()
+    if (@import("builtin").os.tag == .linux) {
+        @cInclude("sys/vfs.h"); // statfs()
+    }
+    @cInclude("curses.h");
+    @cInclude("zstd.h");
+});

src/delete.zig

@@ -6,7 +6,11 @@ const main = @import("main.zig");
 const model = @import("model.zig");
 const ui = @import("ui.zig");
 const browser = @import("browser.zig");
+const scan = @import("scan.zig");
+const sink = @import("sink.zig");
+const mem_sink = @import("mem_sink.zig");
 const util = @import("util.zig");
+const c = @import("c.zig").c;
 
 var parent: *model.Dir = undefined;
 var entry: *model.Entry = undefined;
@@ -67,6 +71,57 @@ fn deleteItem(dir: std.fs.Dir, path: [:0]const u8, ptr: *align(1) ?*model.Entry)
     return false;
 }
 
+// Returns true if the item has been deleted successfully.
+fn deleteCmd(path: [:0]const u8, ptr: *align(1) ?*model.Entry) bool {
+    {
+        var env = std.process.getEnvMap(main.allocator) catch unreachable;
+        defer env.deinit();
+        env.put("NCDU_DELETE_PATH", path) catch unreachable;
+
+        // Since we're passing the path as an environment variable and go through
+        // the shell anyway, we can refer to the variable and avoid error-prone
+        // shell escaping.
+        const cmd = std.fmt.allocPrint(main.allocator, "{s} \"$NCDU_DELETE_PATH\"", .{main.config.delete_command}) catch unreachable;
+        defer main.allocator.free(cmd);
+        ui.runCmd(&.{"/bin/sh", "-c", cmd}, null, &env, true);
+    }
+
+    const stat = scan.statAt(std.fs.cwd(), path, false, null) catch {
+        // Stat failed. Would be nice to display an error if it's not
+        // 'FileNotFound', but w/e, let's just assume the item has been
+        // deleted as expected.
+        ptr.*.?.zeroStats(parent);
+        ptr.* = ptr.*.?.next.ptr;
+        return true;
+    };
+
+    // If either old or new entry is not a dir, remove & re-add entry in the in-memory tree.
+    if (ptr.*.?.pack.etype != .dir or stat.etype != .dir) {
+        ptr.*.?.zeroStats(parent);
+        const e = model.Entry.create(main.allocator, stat.etype, main.config.extended and !stat.ext.isEmpty(), ptr.*.?.name());
+        e.next.ptr = ptr.*.?.next.ptr;
+        mem_sink.statToEntry(&stat, e, parent);
+        ptr.* = e;
+
+        var it : ?*model.Dir = parent;
+        while (it) |p| : (it = p.parent) {
+            if (stat.etype != .link) {
+                p.entry.pack.blocks +|= e.pack.blocks;
+                p.entry.size +|= e.size;
+            }
+            p.items +|= 1;
+        }
+    }
+
+    // If new entry is a dir, recursively scan.
+    if (ptr.*.?.dir()) |d| {
+        main.state = .refresh;
+        sink.global.sink = .mem;
+        mem_sink.global.root = d;
+    }
+    return false;
+}
+
 // Returns the item that should be selected in the browser.
 pub fn delete() ?*model.Entry {
     while (main.state == .delete and state == .confirm)
@@ -81,22 +136,29 @@ pub fn delete() ?*model.Entry {
         if (it.* == entry)
             break;
 
-    var path = std.ArrayList(u8).init(main.allocator);
+    var path: std.ArrayListUnmanaged(u8) = .empty;
-    defer path.deinit();
+    defer path.deinit(main.allocator);
-    parent.fmtPath(true, &path);
+    parent.fmtPath(main.allocator, true, &path);
     if (path.items.len == 0 or path.items[path.items.len-1] != '/')
-        path.append('/') catch unreachable;
+        path.append(main.allocator, '/') catch unreachable;
-    path.appendSlice(entry.name()) catch unreachable;
+    path.appendSlice(main.allocator, entry.name()) catch unreachable;
 
-    _ = deleteItem(std.fs.cwd(), util.arrayListBufZ(&path), it);
+    if (main.config.delete_command.len == 0) {
+        _ = deleteItem(std.fs.cwd(), util.arrayListBufZ(&path, main.allocator), it);
         model.inodes.addAllStats();
         return if (it.* == e) e else next_sel;
+    } else {
+        const isdel = deleteCmd(util.arrayListBufZ(&path, main.allocator), it);
+        model.inodes.addAllStats();
+        return if (isdel) next_sel else it.*;
+    }
 }
 
 fn drawConfirm() void {
     browser.draw();
     const box = ui.Box.create(6, 60, "Confirm delete");
     box.move(1, 2);
+    if (main.config.delete_command.len == 0) {
         ui.addstr("Are you sure you want to delete \"");
         ui.addstr(ui.shorten(ui.toUtf8(entry.name()), 21));
         ui.addch('"');
@@ -106,6 +168,15 @@ fn drawConfirm() void {
             box.move(2, 18);
             ui.addstr("and all of its contents?");
         }
+    } else {
+        ui.addstr("Are you sure you want to run \"");
+        ui.addstr(ui.shorten(ui.toUtf8(main.config.delete_command), 25));
+        ui.addch('"');
+        box.move(2, 4);
+        ui.addstr("on \"");
+        ui.addstr(ui.shorten(ui.toUtf8(entry.name()), 50));
+        ui.addch('"');
+    }
 
     box.move(4, 15);
     ui.style(if (confirm == .yes) .sel else .default);
@@ -118,20 +189,25 @@ fn drawConfirm() void {
     box.move(4, 31);
     ui.style(if (confirm == .ignore) .sel else .default);
     ui.addstr("don't ask me again");
+    box.move(4, switch (confirm) {
+        .yes    => 15,
+        .no     => 25,
+        .ignore => 31
+    });
 }
 
 fn drawProgress() void {
-    var path = std.ArrayList(u8).init(main.allocator);
+    var path: std.ArrayListUnmanaged(u8) = .empty;
-    defer path.deinit();
+    defer path.deinit(main.allocator);
-    parent.fmtPath(false, &path);
+    parent.fmtPath(main.allocator, false, &path);
-    path.append('/') catch unreachable;
+    path.append(main.allocator, '/') catch unreachable;
-    path.appendSlice(entry.name()) catch unreachable;
+    path.appendSlice(main.allocator, entry.name()) catch unreachable;
 
     // TODO: Item counts and progress bar would be nice.
 
     const box = ui.Box.create(6, 60, "Deleting...");
     box.move(2, 2);
-    ui.addstr(ui.shorten(ui.toUtf8(util.arrayListBufZ(&path)), 56));
+    ui.addstr(ui.shorten(ui.toUtf8(util.arrayListBufZ(&path, main.allocator)), 56));
     box.move(4, 41);
     ui.addstr("Press ");
     ui.style(.key);
@@ -141,16 +217,16 @@ fn drawProgress() void {
 }
 
 fn drawErr() void {
-    var path = std.ArrayList(u8).init(main.allocator);
+    var path: std.ArrayListUnmanaged(u8) = .empty;
-    defer path.deinit();
+    defer path.deinit(main.allocator);
-    parent.fmtPath(false, &path);
+    parent.fmtPath(main.allocator, false, &path);
-    path.append('/') catch unreachable;
+    path.append(main.allocator, '/') catch unreachable;
-    path.appendSlice(entry.name()) catch unreachable;
+    path.appendSlice(main.allocator, entry.name()) catch unreachable;
 
     const box = ui.Box.create(6, 60, "Error");
     box.move(1, 2);
     ui.addstr("Error deleting ");
-    ui.addstr(ui.shorten(ui.toUtf8(util.arrayListBufZ(&path)), 41));
+    ui.addstr(ui.shorten(ui.toUtf8(util.arrayListBufZ(&path, main.allocator)), 41));
     box.move(2, 4);
     ui.addstr(ui.errorString(error_code));
 
@@ -178,11 +254,11 @@ pub fn draw() void {
 pub fn keyInput(ch: i32) void {
     switch (state) {
         .confirm => switch (ch) {
-            'h', ui.c.KEY_LEFT => confirm = switch (confirm) {
+            'h', c.KEY_LEFT => confirm = switch (confirm) {
                 .ignore => .no,
                 else => .yes,
             },
-            'l', ui.c.KEY_RIGHT => confirm = switch (confirm) {
+            'l', c.KEY_RIGHT => confirm = switch (confirm) {
                 .yes => .no,
                 else => .ignore,
             },
@@ -202,11 +278,11 @@ pub fn keyInput(ch: i32) void {
                 main.state = .browse;
         },
         .err => switch (ch) {
-            'h', ui.c.KEY_LEFT => error_option = switch (error_option) {
+            'h', c.KEY_LEFT => error_option = switch (error_option) {
                 .all => .ignore,
                 else => .abort,
             },
-            'l', ui.c.KEY_RIGHT => error_option = switch (error_option) {
+            'l', c.KEY_RIGHT => error_option = switch (error_option) {
                 .abort => .ignore,
                 else => .all,
             },

src/exclude.zig

@@ -3,7 +3,7 @@
 
 const std = @import("std");
 const main = @import("main.zig");
-const c = @cImport(@cInclude("fnmatch.h"));
+const c = @import("c.zig").c;
 
 // Reference:
 //   https://manned.org/glob.7
@@ -123,7 +123,7 @@ test "parse" {
 fn PatternList(comptime withsub: bool) type {
     return struct {
         literals: std.HashMapUnmanaged(*const Pattern, Val, Ctx, 80) = .{},
-        wild: std.ArrayListUnmanaged(*const Pattern) = .{},
+        wild: std.ArrayListUnmanaged(*const Pattern) = .empty,
 
         // Not a fan of the map-of-arrays approach in the 'withsub' case, it
         // has a lot of extra allocations. Linking the Patterns together in a

src/json_export.zig

@@ -7,6 +7,7 @@ const model = @import("model.zig");
 const sink = @import("sink.zig");
 const util = @import("util.zig");
 const ui = @import("ui.zig");
+const c = @import("c.zig").c;
 
 // JSON output is necessarily single-threaded and items MUST be added depth-first.
 
@@ -14,8 +15,55 @@ pub const global = struct {
     var writer: *Writer = undefined;
 };
 
+
+const ZstdWriter = struct {
+    ctx: ?*c.ZSTD_CStream,
+    out: c.ZSTD_outBuffer,
+    outbuf: [c.ZSTD_BLOCKSIZE_MAX + 64]u8,
+
+    fn create() *ZstdWriter {
+        const w = main.allocator.create(ZstdWriter) catch unreachable;
+        w.out = .{
+            .dst = &w.outbuf,
+            .size = w.outbuf.len,
+            .pos = 0,
+        };
+        while (true) {
+            w.ctx = c.ZSTD_createCStream();
+            if (w.ctx != null) break;
+            ui.oom();
+        }
+        _ = c.ZSTD_CCtx_setParameter(w.ctx, c.ZSTD_c_compressionLevel, main.config.complevel);
+        return w;
+    }
+
+    fn destroy(w: *ZstdWriter) void {
+        _ = c.ZSTD_freeCStream(w.ctx);
+        main.allocator.destroy(w);
+    }
+
+    fn write(w: *ZstdWriter, f: std.fs.File, in: []const u8, flush: bool) !void {
+        var arg = c.ZSTD_inBuffer{
+            .src = in.ptr,
+            .size = in.len,
+            .pos = 0,
+        };
+        while (true) {
+            const v = c.ZSTD_compressStream2(w.ctx, &w.out, &arg, if (flush) c.ZSTD_e_end else c.ZSTD_e_continue);
+            if (c.ZSTD_isError(v) != 0) return error.ZstdCompressError;
+            if (flush or w.out.pos > w.outbuf.len / 2) {
+                try f.writeAll(w.outbuf[0..w.out.pos]);
+                w.out.pos = 0;
+            }
+            if (!flush and arg.pos == arg.size) break;
+            if (flush and v == 0) break;
+        }
+    }
+};
+
 pub const Writer = struct {
     fd: std.fs.File,
+    zstd: ?*ZstdWriter = null,
     // Must be large enough to hold PATH_MAX*6 plus some overhead.
     // (The 6 is because, in the worst case, every byte expands to a "\u####"
     // escape, and we do pessimistic estimates here in order to avoid checking
@@ -25,11 +73,12 @@ pub const Writer = struct {
     dir_entry_open: bool = false,
 
     fn flush(ctx: *Writer, bytes: usize) void {
-        @setCold(true);
+        @branchHint(.unlikely);
         // This can only really happen when the root path exceeds PATH_MAX,
         // in which case we would probably have error'ed out earlier anyway.
         if (bytes > ctx.buf.len) ui.die("Error writing JSON export: path too long.\n", .{});
-        ctx.fd.writeAll(ctx.buf[0..ctx.off]) catch |e|
+        const buf = ctx.buf[0..ctx.off];
+        (if (ctx.zstd) |z| z.write(ctx.fd, buf, bytes == 0) else ctx.fd.writeAll(buf)) catch |e|
             ui.die("Error writing to file: {s}.\n", .{ ui.errorString(e) });
         ctx.off = 0;
     }
@@ -77,14 +126,14 @@ pub const Writer = struct {
         var index: usize = buf.len;
         while (a >= 100) : (a = @divTrunc(a, 100)) {
             index -= 2;
-            buf[index..][0..2].* = std.fmt.digits2(@as(usize, @intCast(a % 100)));
+            buf[index..][0..2].* = std.fmt.digits2(@as(u8, @intCast(a % 100)));
         }
         if (a < 10) {
             index -= 1;
             buf[index] = '0' + @as(u8, @intCast(a));
         } else {
             index -= 2;
-            buf[index..][0..2].* = std.fmt.digits2(@as(usize, @intCast(a)));
+            buf[index..][0..2].* = std.fmt.digits2(@as(u8, @intCast(a)));
         }
         ctx.write(buf[index..]);
     }
@@ -92,6 +141,7 @@ pub const Writer = struct {
     fn init(out: std.fs.File) *Writer {
         var ctx = main.allocator.create(Writer) catch unreachable;
         ctx.* = .{ .fd = out };
+        if (main.config.compress) ctx.zstd = ZstdWriter.create();
         ctx.write("[1,2,{\"progname\":\"ncdu\",\"progver\":\"" ++ main.program_version ++ "\",\"timestamp\":");
         ctx.writeUint(@intCast(@max(0, std.time.timestamp())));
         ctx.writeByte('}');
@@ -210,6 +260,7 @@ pub fn createRoot(path: []const u8, stat: *const sink.Stat) Dir {
 pub fn done() void {
     global.writer.write("]\n");
     global.writer.flush(0);
+    if (global.writer.zstd) |z| z.destroy();
     global.writer.fd.close();
     main.allocator.destroy(global.writer);
 }

src/json_import.zig

@@ -7,6 +7,54 @@ const util = @import("util.zig");
 const model = @import("model.zig");
 const sink = @import("sink.zig");
 const ui = @import("ui.zig");
+const c = @import("c.zig").c;
+
+
+const ZstdReader = struct {
+    ctx: ?*c.ZSTD_DStream,
+    in: c.ZSTD_inBuffer,
+    lastret: usize = 0,
+    inbuf: [c.ZSTD_BLOCKSIZE_MAX + 16]u8, // This ZSTD_DStreamInSize() + a little bit extra
+
+    fn create(head: []const u8) *ZstdReader {
+        const r = main.allocator.create(ZstdReader) catch unreachable;
+        @memcpy(r.inbuf[0..head.len], head);
+        r.in = .{
+            .src = &r.inbuf,
+            .size = head.len,
+            .pos = 0,
+        };
+        while (true) {
+            r.ctx = c.ZSTD_createDStream();
+            if (r.ctx != null) break;
+            ui.oom();
+        }
+        return r;
+    }
+
+    fn destroy(r: *ZstdReader) void {
+        _ = c.ZSTD_freeDStream(r.ctx);
+        main.allocator.destroy(r);
+    }
+
+    fn read(r: *ZstdReader, f: std.fs.File, out: []u8) !usize {
+        while (true) {
+            if (r.in.size == r.in.pos) {
+                r.in.pos = 0;
+                r.in.size = try f.read(&r.inbuf);
+                if (r.in.size == 0) {
+                    if (r.lastret == 0) return 0;
+                    return error.ZstdDecompressError; // Early EOF
+                }
+            }
+
+            var arg = c.ZSTD_outBuffer{ .dst = out.ptr, .size = out.len, .pos = 0 };
+            r.lastret = c.ZSTD_decompressStream(r.ctx, &arg, &r.in);
+            if (c.ZSTD_isError(r.lastret) != 0) return error.ZstdDecompressError;
+            if (arg.pos > 0) return arg.pos;
+        }
+    }
+};
 
 
 // Using a custom JSON parser here because, while std.json is great, it does
@@ -16,11 +64,12 @@ const ui = @import("ui.zig");
 
 const Parser = struct {
     rd: std.fs.File,
+    zstd: ?*ZstdReader = null,
     rdoff: usize = 0,
     rdsize: usize = 0,
     byte: u64 = 1,
     line: u64 = 1,
-    buf: [16*1024]u8 = undefined,
+    buf: [129*1024]u8 = undefined,
 
     fn die(p: *Parser, str: []const u8) noreturn {
         ui.die("Error importing file on line {}:{}: {s}.\n", .{ p.line, p.byte, str });
@@ -34,11 +83,11 @@ const Parser = struct {
     }
 
     fn fill(p: *Parser) void {
-        @setCold(true);
         p.rdoff = 0;
-        p.rdsize = p.rd.read(&p.buf) catch |e| switch (e) {
+        p.rdsize = (if (p.zstd) |z| z.read(p.rd, &p.buf) else p.rd.read(&p.buf)) catch |e| switch (e) {
             error.IsDir => p.die("not a file"), // should be detected at open() time, but no flag for that...
             error.SystemResources => p.die("out of memory"),
+            error.ZstdDecompressError => p.die("decompression error"),
             else => p.die("I/O error"),
         };
     }
@@ -48,6 +97,7 @@ const Parser = struct {
     // (Returning a '?u8' here is nicer but kills performance by about +30%)
     fn nextByte(p: *Parser) u8 {
         if (p.rdoff == p.rdsize) {
+            @branchHint(.unlikely);
             p.fill();
             if (p.rdsize == 0) return 0;
         }
@@ -83,7 +133,7 @@ const Parser = struct {
     }
 
     fn stringContentSlow(p: *Parser, buf: []u8, head: u8, off: usize) []u8 {
-        @setCold(true);
+        @branchHint(.unlikely);
         var b = head;
         var n = off;
         while (true) {
@@ -99,9 +149,16 @@ const Parser = struct {
                     'r' => if (n < buf.len) { buf[n] = 0xd; n += 1; },
                     't' => if (n < buf.len) { buf[n] = 0x9; n += 1; },
                     'u' => {
-                        const char = (p.hexdig()<<12) + (p.hexdig()<<8) + (p.hexdig()<<4) + p.hexdig();
+                        const first = (p.hexdig()<<12) + (p.hexdig()<<8) + (p.hexdig()<<4) + p.hexdig();
+                        var unit = @as(u21, first);
+                        if (std.unicode.utf16IsLowSurrogate(first)) p.die("Unexpected low surrogate");
+                        if (std.unicode.utf16IsHighSurrogate(first)) {
+                            p.expectLit("\\u");
+                            const second = (p.hexdig()<<12) + (p.hexdig()<<8) + (p.hexdig()<<4) + p.hexdig();
+                            unit = std.unicode.utf16DecodeSurrogatePair(&.{first, second}) catch p.die("Invalid low surrogate");
+                        }
                         if (n + 6 < buf.len)
-                            n += std.unicode.utf8Encode(char, buf[n..n+5]) catch unreachable;
+                            n += std.unicode.utf8Encode(unit, buf[n..n+5]) catch unreachable;
                     },
                     else => p.die("invalid escape sequence"),
                 },
@@ -475,8 +532,15 @@ pub fn import(fd: std.fs.File, head: []const u8) void {
     const sink_threads = sink.createThreads(1);
     defer sink.done();
 
-    var p = Parser{.rd = fd, .rdsize = head.len};
+    var p = Parser{.rd = fd};
+    defer if (p.zstd) |z| z.destroy();
+
+    if (head.len >= 4 and std.mem.eql(u8, head[0..4], "\x28\xb5\x2f\xfd")) {
+        p.zstd = ZstdReader.create(head);
+    } else {
+        p.rdsize = head.len;
         @memcpy(p.buf[0..head.len], head);
+    }
     p.array();
     if (p.uint(u16) != 1) p.die("incompatible major format version");
     if (!p.elem(false)) p.die("expected array element");

src/main.zig

@@ -1,7 +1,7 @@
 // SPDX-FileCopyrightText: Yorhel <projects@yorhel.nl>
 // SPDX-License-Identifier: MIT
 
-pub const program_version = "2.6";
+pub const program_version = "2.9.2";
 
 const std = @import("std");
 const model = @import("model.zig");
@@ -18,7 +18,7 @@ const browser = @import("browser.zig");
 const delete = @import("delete.zig");
 const util = @import("util.zig");
 const exclude = @import("exclude.zig");
-const c = @cImport(@cInclude("locale.h"));
+const c = @import("c.zig").c;
 
 test "imports" {
     _ = model;
@@ -41,7 +41,7 @@ test "imports" {
 // This allocator never returns an error, it either succeeds or causes ncdu to quit.
 // (Which means you'll find a lot of "catch unreachable" sprinkled through the code,
 // they look scarier than they are)
-fn wrapAlloc(_: *anyopaque, len: usize, ptr_alignment: u8, return_address: usize) ?[*]u8 {
+fn wrapAlloc(_: *anyopaque, len: usize, ptr_alignment: std.mem.Alignment, return_address: usize) ?[*]u8 {
     while (true) {
         if (std.heap.c_allocator.vtable.alloc(undefined, len, ptr_alignment, return_address)) |r|
             return r
@@ -56,18 +56,20 @@ pub const allocator = std.mem.Allocator{
         .alloc = wrapAlloc,
         // AFAIK, all uses of resize() to grow an allocation will fall back to alloc() on failure.
         .resize = std.heap.c_allocator.vtable.resize,
+        .remap = std.heap.c_allocator.vtable.remap,
         .free = std.heap.c_allocator.vtable.free,
     },
 };
 
 
 // Custom panic impl to reset the terminal before spewing out an error message.
-pub fn panic(msg: []const u8, error_return_trace: ?*std.builtin.StackTrace, ret_addr: ?usize) noreturn {
+pub const panic = std.debug.FullPanic(struct {
-    @setCold(true);
+    pub fn panicFn(msg: []const u8, first_trace_addr: ?usize) noreturn {
+        @branchHint(.cold);
         ui.deinit();
-    std.debug.panicImpl(error_return_trace, ret_addr orelse @returnAddress(), msg);
+        std.debug.defaultPanic(msg, first_trace_addr);
     }
-
+}.panicFn);
 
 pub const config = struct {
     pub const SortCol = enum { name, blocks, size, items, mtime };
@@ -78,9 +80,10 @@ pub const config = struct {
     pub var follow_symlinks: bool = false;
     pub var exclude_caches: bool = false;
     pub var exclude_kernfs: bool = false;
-    pub var exclude_patterns: std.ArrayList([:0]const u8) = std.ArrayList([:0]const u8).init(allocator);
     pub var threads: usize = 1;
     pub var complevel: u8 = 4;
+    pub var compress: bool = false;
+    pub var export_block_size: ?usize = null;
 
     pub var update_delay: u64 = 100*std.time.ns_per_ms;
     pub var scan_ui: ?enum { none, line, full } = null;
@@ -110,10 +113,14 @@ pub const config = struct {
     pub var confirm_quit: bool = false;
     pub var confirm_delete: bool = true;
     pub var ignore_delete_errors: bool = false;
+    pub var delete_command: [:0]const u8 = "";
 };
 
 pub var state: enum { scan, browse, refresh, shell, delete } = .scan;
 
+const stdin = if (@hasDecl(std.io, "getStdIn")) std.io.getStdIn() else std.fs.File.stdin();
+const stdout = if (@hasDecl(std.io, "getStdOut")) std.io.getStdOut() else std.fs.File.stdout();
+
 // Simple generic argument parser, supports getopt_long() style arguments.
 const Args = struct {
     lst: []const [:0]const u8,
@@ -122,6 +129,7 @@ const Args = struct {
     last_arg: ?[:0]const u8 = null, // In the case of --option=<arg>
     shortbuf: [2]u8 = undefined,
     argsep: bool = false,
+    ignerror: bool = false,
 
     const Self = @This();
     const Option = struct {
@@ -151,22 +159,27 @@ const Args = struct {
         return .{ .opt = true, .val = &self.shortbuf };
     }
 
+    pub fn die(self: *const Self, comptime msg: []const u8, args: anytype) !noreturn {
+        if (self.ignerror) return error.InvalidArg;
+        ui.die(msg, args);
+    }
+
     /// Return the next option or positional argument.
     /// 'opt' indicates whether it's an option or positional argument,
     /// 'val' will be either -x, --something or the argument.
-    pub fn next(self: *Self) ?Option {
+    pub fn next(self: *Self) !?Option {
-        if (self.last_arg != null) ui.die("Option '{s}' does not expect an argument.\n", .{ self.last.? });
+        if (self.last_arg != null) try self.die("Option '{s}' does not expect an argument.\n", .{ self.last.? });
         if (self.short) |s| return self.shortopt(s);
         const val = self.pop() orelse return null;
         if (self.argsep or val.len == 0 or val[0] != '-') return Option{ .opt = false, .val = val };
-        if (val.len == 1) ui.die("Invalid option '-'.\n", .{});
+        if (val.len == 1) try self.die("Invalid option '-'.\n", .{});
         if (val.len == 2 and val[1] == '-') {
             self.argsep = true;
             return self.next();
         }
         if (val[1] == '-') {
             if (std.mem.indexOfScalar(u8, val, '=')) |sep| {
-                if (sep == 2) ui.die("Invalid option '{s}'.\n", .{val});
+                if (sep == 2) try self.die("Invalid option '{s}'.\n", .{val});
                 self.last_arg = val[sep+1.. :0];
                 self.last = val[0..sep];
                 return Option{ .opt = true, .val = self.last.? };
@@ -178,7 +191,7 @@ const Args = struct {
     }
 
     /// Returns the argument given to the last returned option. Dies with an error if no argument is provided.
-    pub fn arg(self: *Self) [:0]const u8 {
+    pub fn arg(self: *Self) ![:0]const u8 {
         if (self.short) |a| {
             defer self.short = null;
             return a;
@@ -188,11 +201,11 @@ const Args = struct {
             return a;
         }
         if (self.pop()) |o| return o;
-        ui.die("Option '{s}' requires an argument.\n", .{ self.last.? });
+        try self.die("Option '{s}' requires an argument.\n", .{ self.last.? });
     }
 };
 
-fn argConfig(args: *Args, opt: Args.Option) bool {
+fn argConfig(args: *Args, opt: Args.Option, infile: bool) !void {
     if (opt.is("-q") or opt.is("--slow-ui-updates")) config.update_delay = 2*std.time.ns_per_s
     else if (opt.is("--fast-ui-updates")) config.update_delay = 100*std.time.ns_per_ms
     else if (opt.is("-x") or opt.is("--one-file-system")) config.same_fs = true
@@ -222,13 +235,13 @@ fn argConfig(args: *Args, opt: Args.Option) bool {
     else if (opt.is("--enable-natsort")) config.sort_natural = true
     else if (opt.is("--disable-natsort")) config.sort_natural = false
     else if (opt.is("--graph-style")) {
-        const val = args.arg();
+        const val = try args.arg();
         if (std.mem.eql(u8, val, "hash")) config.graph_style = .hash
         else if (std.mem.eql(u8, val, "half-block")) config.graph_style = .half
         else if (std.mem.eql(u8, val, "eighth-block") or std.mem.eql(u8, val, "eigth-block")) config.graph_style = .eighth
-        else ui.die("Unknown --graph-style option: {s}.\n", .{val});
+        else try args.die("Unknown --graph-style option: {s}.\n", .{val});
     } else if (opt.is("--sort")) {
-        var val: []const u8 = args.arg();
+        var val: []const u8 = try args.arg();
         var ord: ?config.SortOrder = null;
         if (std.mem.endsWith(u8, val, "-asc")) {
             val = val[0..val.len-4];
@@ -252,13 +265,13 @@ fn argConfig(args: *Args, opt: Args.Option) bool {
         } else if (std.mem.eql(u8, val, "mtime")) {
             config.sort_col = .mtime;
             config.sort_order = ord orelse .asc;
-        } else ui.die("Unknown --sort option: {s}.\n", .{val});
+        } else try args.die("Unknown --sort option: {s}.\n", .{val});
     } else if (opt.is("--shared-column")) {
-        const val = args.arg();
+        const val = try args.arg();
         if (std.mem.eql(u8, val, "off")) config.show_shared = .off
         else if (std.mem.eql(u8, val, "shared")) config.show_shared = .shared
         else if (std.mem.eql(u8, val, "unique")) config.show_shared = .unique
-        else ui.die("Unknown --shared-column option: {s}.\n", .{val});
+        else try args.die("Unknown --shared-column option: {s}.\n", .{val});
     } else if (opt.is("--apparent-size")) config.show_blocks = false
     else if (opt.is("--disk-usage")) config.show_blocks = true
     else if (opt.is("-0")) config.scan_ui = .none
@@ -268,33 +281,45 @@ fn argConfig(args: *Args, opt: Args.Option) bool {
     else if (opt.is("--no-si")) config.si = false
     else if (opt.is("-L") or opt.is("--follow-symlinks")) config.follow_symlinks = true
     else if (opt.is("--no-follow-symlinks")) config.follow_symlinks = false
-    else if (opt.is("--exclude")) exclude.addPattern(args.arg())
+    else if (opt.is("--exclude")) {
-    else if (opt.is("-X") or opt.is("--exclude-from")) {
+        const arg = if (infile) (util.expanduser(try args.arg(), allocator) catch unreachable) else try args.arg();
-        const arg = args.arg();
+        defer if (infile) allocator.free(arg);
-        readExcludeFile(arg) catch |e| ui.die("Error reading excludes from {s}: {s}.\n", .{ arg, ui.errorString(e) });
+        exclude.addPattern(arg);
+    } else if (opt.is("-X") or opt.is("--exclude-from")) {
+        const arg = if (infile) (util.expanduser(try args.arg(), allocator) catch unreachable) else try args.arg();
+        defer if (infile) allocator.free(arg);
+        readExcludeFile(arg) catch |e| try args.die("Error reading excludes from {s}: {s}.\n", .{ arg, ui.errorString(e) });
     } else if (opt.is("--exclude-caches")) config.exclude_caches = true
     else if (opt.is("--include-caches")) config.exclude_caches = false
     else if (opt.is("--exclude-kernfs")) config.exclude_kernfs = true
     else if (opt.is("--include-kernfs")) config.exclude_kernfs = false
+    else if (opt.is("-c") or opt.is("--compress")) config.compress = true
+    else if (opt.is("--no-compress")) config.compress = false
     else if (opt.is("--compress-level")) {
-        const val = args.arg();
+        const val = try args.arg();
-        config.complevel = std.fmt.parseInt(u8, val, 10) catch ui.die("Invalid number for --compress-level: {s}.\n", .{val});
+        const num = std.fmt.parseInt(u8, val, 10) catch try args.die("Invalid number for --compress-level: {s}.\n", .{val});
-        if (config.complevel <= 0 or config.complevel > 20) ui.die("Invalid number for --compress-level: {s}.\n", .{val});
+        if (num <= 0 or num > 20) try args.die("Invalid number for --compress-level: {s}.\n", .{val});
+        config.complevel = num;
+    } else if (opt.is("--export-block-size")) {
+        const val = try args.arg();
+        const num = std.fmt.parseInt(u14, val, 10) catch try args.die("Invalid number for --export-block-size: {s}.\n", .{val});
+        if (num < 4 or num > 16000) try args.die("Invalid number for --export-block-size: {s}.\n", .{val});
+        config.export_block_size = @as(usize, num) * 1024;
     } else if (opt.is("--confirm-quit")) config.confirm_quit = true
     else if (opt.is("--no-confirm-quit")) config.confirm_quit = false
     else if (opt.is("--confirm-delete")) config.confirm_delete = true
     else if (opt.is("--no-confirm-delete")) config.confirm_delete = false
+    else if (opt.is("--delete-command")) config.delete_command = allocator.dupeZ(u8, try args.arg()) catch unreachable
     else if (opt.is("--color")) {
-        const val = args.arg();
+        const val = try args.arg();
         if (std.mem.eql(u8, val, "off")) config.ui_color = .off
         else if (std.mem.eql(u8, val, "dark")) config.ui_color = .dark
         else if (std.mem.eql(u8, val, "dark-bg")) config.ui_color = .darkbg
-        else ui.die("Unknown --color option: {s}.\n", .{val});
+        else try args.die("Unknown --color option: {s}.\n", .{val});
     } else if (opt.is("-t") or opt.is("--threads")) {
-        const val = args.arg();
+        const val = try args.arg();
-        config.threads = std.fmt.parseInt(u8, val, 10) catch ui.die("Invalid number of --threads: {s}.\n", .{val});
+        config.threads = std.fmt.parseInt(u8, val, 10) catch try args.die("Invalid number of --threads: {s}.\n", .{val});
-    } else return false;
+    } else return error.UnknownOption;
-    return true;
 }
 
 fn tryReadArgsFile(path: [:0]const u8) void {
@@ -305,148 +330,117 @@ fn tryReadArgsFile(path: [:0]const u8) void {
     };
     defer f.close();
 
-    var arglist = std.ArrayList([:0]const u8).init(allocator);
-
-    var rd_ = std.io.bufferedReader(f.reader());
-    const rd = rd_.reader();
-
     var line_buf: [4096]u8 = undefined;
-    var line_fbs = std.io.fixedBufferStream(&line_buf);
+    var line_rd = util.LineReader.init(f, &line_buf);
-    const line_writer = line_fbs.writer();
 
-    while (true) : (line_fbs.reset()) {
+    while (true) {
-        rd.streamUntilDelimiter(line_writer, '\n', line_buf.len) catch |err| switch (err) {
+        const line_ = (line_rd.read() catch |e|
-            error.EndOfStream => if (line_fbs.getPos() catch unreachable == 0) break,
+            ui.die("Error reading from {s}: {s}\nRun with --ignore-config to skip reading config files.\n", .{ path, ui.errorString(e) })
-            else => |e| ui.die("Error reading from {s}: {s}\nRun with --ignore-config to skip reading config files.\n", .{ path, ui.errorString(e) }),
+        ) orelse break;
-        };
+
-        const line_ = line_fbs.getWritten();
+        var argc: usize = 0;
+        var ignerror = false;
+        var arglist: [2][:0]const u8 = .{ "", "" };
 
         var line = std.mem.trim(u8, line_, &std.ascii.whitespace);
+        if (line.len > 0 and line[0] == '@') {
+            ignerror = true;
+            line = line[1..];
+        }
         if (line.len == 0 or line[0] == '#') continue;
         if (std.mem.indexOfAny(u8, line, " \t=")) |i| {
-            arglist.append(allocator.dupeZ(u8, line[0..i]) catch unreachable) catch unreachable;
+            arglist[argc] = allocator.dupeZ(u8, line[0..i]) catch unreachable;
+            argc += 1;
             line = std.mem.trimLeft(u8, line[i+1..], &std.ascii.whitespace);
         }
-        arglist.append(allocator.dupeZ(u8, line) catch unreachable) catch unreachable;
+        arglist[argc] = allocator.dupeZ(u8, line) catch unreachable;
-    }
+        argc += 1;
 
-    var args = Args.init(arglist.items);
+        var args = Args.init(arglist[0..argc]);
-    while (args.next()) |opt| {
+        args.ignerror = ignerror;
-        if (!argConfig(&args, opt))
+        while (args.next() catch null) |opt| {
+            if (argConfig(&args, opt, true)) |_| {}
+            else |_| {
+                if (ignerror) break;
                 ui.die("Unrecognized option in config file '{s}': {s}.\nRun with --ignore-config to skip reading config files.\n", .{path, opt.val});
             }
-    for (arglist.items) |i| allocator.free(i);
+        }
-    arglist.deinit();
+        allocator.free(arglist[0]);
+        if (argc == 2) allocator.free(arglist[1]);
+    }
 }
 
 fn version() noreturn {
-    const stdout = std.io.getStdOut();
     stdout.writeAll("ncdu " ++ program_version ++ "\n") catch {};
     std.process.exit(0);
 }
 
 fn help() noreturn {
-    const stdout = std.io.getStdOut();
     stdout.writeAll(
     \\ncdu <options> <directory>
     \\
-    \\Options:
+    \\Mode selection:
     \\  -h, --help                 This help message
-    \\  -q                         Quiet mode, refresh interval 2 seconds
     \\  -v, -V, --version          Print version
-    \\  -x                         Same filesystem
-    \\  -e                         Enable extended information
-    \\  -t NUM                     Number of threads to use
-    \\  -r                         Read only
-    \\  -o FILE                    Export scanned directory to FILE
     \\  -f FILE                    Import scanned directory from FILE
-    \\  -0,-1,-2                   UI to use when scanning (0=none,2=full ncurses)
+    \\  -o FILE                    Export scanned directory to FILE in JSON format
-    \\  --si                       Use base 10 (SI) prefixes instead of base 2
+    \\  -O FILE                    Export scanned directory to FILE in binary format
-    \\  --exclude PATTERN          Exclude files that match PATTERN
+    \\  -e, --extended             Enable extended information
-    \\  -X, --exclude-from FILE    Exclude files that match any pattern in FILE
-    \\  -L, --follow-symlinks      Follow symbolic links (excluding directories)
-    \\  --exclude-caches           Exclude directories containing CACHEDIR.TAG
-    \\  --exclude-kernfs           Exclude Linux pseudo filesystems (procfs,sysfs,cgroup,...)
-    \\  --confirm-quit             Confirm quitting ncdu
-    \\  --color SCHEME             Set color scheme (off/dark/dark-bg)
     \\  --ignore-config            Don't load config files
     \\
-    \\Refer to `man ncdu` for the full list of options.
+    \\Scan options:
+    \\  -x, --one-file-system      Stay on the same filesystem
+    \\  --exclude PATTERN          Exclude files that match PATTERN
+    \\  -X, --exclude-from FILE    Exclude files that match any pattern in FILE
+    \\  --exclude-caches           Exclude directories containing CACHEDIR.TAG
+    \\  -L, --follow-symlinks      Follow symbolic links (excluding directories)
+    \\  --exclude-kernfs           Exclude Linux pseudo filesystems (procfs,sysfs,cgroup,...)
+    \\  -t NUM                     Scan with NUM threads
+    \\
+    \\Export options:
+    \\  -c, --compress             Use Zstandard compression with `-o`
+    \\  --compress-level NUM       Set compression level
+    \\  --export-block-size KIB    Set export block size with `-O`
+    \\
+    \\Interface options:
+    \\  -0, -1, -2                 UI to use when scanning (0=none,2=full ncurses)
+    \\  -q, --slow-ui-updates      "Quiet" mode, refresh interval 2 seconds
+    \\  --enable-shell             Enable/disable shell spawning feature
+    \\  --enable-delete            Enable/disable file deletion feature
+    \\  --enable-refresh           Enable/disable directory refresh feature
+    \\  -r                         Read only (--disable-delete)
+    \\  -rr                        Read only++ (--disable-delete & --disable-shell)
+    \\  --si                       Use base 10 (SI) prefixes instead of base 2
+    \\  --apparent-size            Show apparent size instead of disk usage by default
+    \\  --hide-hidden              Hide "hidden" or excluded files by default
+    \\  --show-itemcount           Show item count column by default
+    \\  --show-mtime               Show mtime column by default (requires `-e`)
+    \\  --show-graph               Show graph column by default
+    \\  --show-percent             Show percent column by default
+    \\  --graph-style STYLE        hash / half-block / eighth-block
+    \\  --shared-column            off / shared / unique
+    \\  --sort COLUMN-(asc/desc)   disk-usage / name / apparent-size / itemcount / mtime
+    \\  --enable-natsort           Use natural order when sorting by name
+    \\  --group-directories-first  Sort directories before files
+    \\  --confirm-quit             Ask confirmation before quitting ncdu
+    \\  --no-confirm-delete        Don't ask confirmation before deletion
+    \\  --delete-command CMD       Command to run for file deletion
+    \\  --color SCHEME             off / dark / dark-bg
+    \\
+    \\Refer to `man ncdu` for more information.
     \\
     ) catch {};
     std.process.exit(0);
 }
 
 
-fn spawnShell() void {
-    ui.deinit();
-    defer ui.init();
-
-    var env = std.process.getEnvMap(allocator) catch unreachable;
-    defer env.deinit();
-    // NCDU_LEVEL can only count to 9, keeps the implementation simple.
-    if (env.get("NCDU_LEVEL")) |l|
-        env.put("NCDU_LEVEL", if (l.len == 0) "1" else switch (l[0]) {
-            '0'...'8' => |d| &[1] u8{d+1},
-            '9' => "9",
-            else => "1"
-        }) catch unreachable
-    else
-        env.put("NCDU_LEVEL", "1") catch unreachable;
-
-    const shell = std.posix.getenvZ("NCDU_SHELL") orelse std.posix.getenvZ("SHELL") orelse "/bin/sh";
-    var child = std.process.Child.init(&.{shell}, allocator);
-    child.cwd = browser.dir_path;
-    child.env_map = &env;
-
-    const stdin = std.io.getStdIn();
-    const stderr = std.io.getStdErr();
-    const term = child.spawnAndWait() catch |e| blk: {
-        stderr.writer().print(
-            "Error spawning shell: {s}\n\nPress enter to continue.\n",
-            .{ ui.errorString(e) }
-        ) catch {};
-        stdin.reader().skipUntilDelimiterOrEof('\n') catch unreachable;
-        break :blk std.process.Child.Term{ .Exited = 0 };
-    };
-    if (term != .Exited) {
-        const n = switch (term) {
-            .Exited  => "status",
-            .Signal  => "signal",
-            .Stopped => "stopped",
-            .Unknown => "unknown",
-        };
-        const v = switch (term) {
-            .Exited  => |v| v,
-            .Signal  => |v| v,
-            .Stopped => |v| v,
-            .Unknown => |v| v,
-        };
-        stderr.writer().print(
-            "Shell returned with {s} code {}.\n\nPress enter to continue.\n", .{ n, v }
-        ) catch {};
-        stdin.reader().skipUntilDelimiterOrEof('\n') catch unreachable;
-    }
-}
-
-
 fn readExcludeFile(path: [:0]const u8) !void {
     const f = try std.fs.cwd().openFileZ(path, .{});
     defer f.close();
 
-    var rd_ = std.io.bufferedReader(f.reader());
-    const rd = rd_.reader();
-
     var line_buf: [4096]u8 = undefined;
-    var line_fbs = std.io.fixedBufferStream(&line_buf);
+    var line_rd = util.LineReader.init(f, &line_buf);
-    const line_writer = line_fbs.writer();
+    while (try line_rd.read()) |line| {
-
-    while (true) : (line_fbs.reset()) {
-        rd.streamUntilDelimiter(line_writer, '\n', line_buf.len) catch |err| switch (err) {
-            error.EndOfStream => if (line_fbs.getPos() catch unreachable == 0) break,
-            else => |e| return e,
-        };
-        const line = line_fbs.getWritten();
         if (line.len > 0)
             exclude.addPattern(line);
     }
@@ -454,13 +448,12 @@ fn readExcludeFile(path: [:0]const u8) !void {
 
 fn readImport(path: [:0]const u8) !void {
     const fd =
-        if (std.mem.eql(u8, "-", path)) std.io.getStdIn()
+        if (std.mem.eql(u8, "-", path)) stdin
         else try std.fs.cwd().openFileZ(path, .{});
     errdefer fd.close();
 
-    // TODO: While we're at it, recognize and handle compressed JSON
     var buf: [8]u8 = undefined;
-    try fd.reader().readNoEof(&buf);
+    if (8 != try fd.readAll(&buf)) return error.EndOfStream;
     if (std.mem.eql(u8, &buf, bin_export.SIGNATURE)) {
         try bin_reader.open(fd);
         config.binreader = true;
@@ -514,8 +507,8 @@ pub fn main() void {
         const arglist = std.process.argsAlloc(allocator) catch unreachable;
         defer std.process.argsFree(allocator, arglist);
         var args = Args.init(arglist);
-        _ = args.next(); // program name
+        _ = args.next() catch unreachable; // program name
-        while (args.next()) |opt| {
+        while (args.next() catch unreachable) |opt| {
             if (!opt.opt) {
                 // XXX: ncdu 1.x doesn't error, it just silently ignores all but the last argument.
                 if (scan_dir != null) ui.die("Multiple directories given, see ncdu -h for help.\n", .{});
@@ -525,15 +518,15 @@ pub fn main() void {
             if (opt.is("-h") or opt.is("-?") or opt.is("--help")) help()
             else if (opt.is("-v") or opt.is("-V") or opt.is("--version")) version()
             else if (opt.is("-o") and (export_json != null or export_bin != null)) ui.die("The -o flag can only be given once.\n", .{})
-            else if (opt.is("-o")) export_json = allocator.dupeZ(u8, args.arg()) catch unreachable
+            else if (opt.is("-o")) export_json = allocator.dupeZ(u8, args.arg() catch unreachable) catch unreachable
             else if (opt.is("-O") and (export_json != null or export_bin != null)) ui.die("The -O flag can only be given once.\n", .{})
-            else if (opt.is("-O")) export_bin = allocator.dupeZ(u8, args.arg()) catch unreachable
+            else if (opt.is("-O")) export_bin = allocator.dupeZ(u8, args.arg() catch unreachable) catch unreachable
             else if (opt.is("-f") and import_file != null) ui.die("The -f flag can only be given once.\n", .{})
-            else if (opt.is("-f")) import_file = allocator.dupeZ(u8, args.arg()) catch unreachable
+            else if (opt.is("-f")) import_file = allocator.dupeZ(u8, args.arg() catch unreachable) catch unreachable
             else if (opt.is("--ignore-config")) {}
             else if (opt.is("--quit-after-scan")) quit_after_scan = true // undocumented feature to help with benchmarking scan/import
-            else if (argConfig(&args, opt)) {}
+            else if (argConfig(&args, opt, false)) |_| {}
-            else ui.die("Unrecognized option '{s}'.\n", .{opt.val});
+            else |_| ui.die("Unrecognized option '{s}'.\n", .{opt.val});
         }
     }
 
@@ -542,8 +535,6 @@ pub fn main() void {
     if (@import("builtin").os.tag != .linux and config.exclude_kernfs)
         ui.die("The --exclude-kernfs flag is currently only supported on Linux.\n", .{});
 
-    const stdin = std.io.getStdIn();
-    const stdout = std.io.getStdOut();
     const out_tty = stdout.isTty();
     const in_tty = stdin.isTty();
     if (config.scan_ui == null) {
@@ -581,7 +572,7 @@ pub fn main() void {
         if (config.binreader and (export_json != null or export_bin != null))
             bin_reader.import();
     } else {
-        var buf = [_]u8{0} ** (std.fs.MAX_PATH_BYTES+1);
+        var buf: [std.fs.max_path_bytes+1]u8 = @splat(0);
         const path =
             if (std.posix.realpathZ(scan_dir orelse ".", buf[0..buf.len-1])) |p| buf[0..p.len:0]
             else |_| (scan_dir orelse ".");
@@ -601,10 +592,10 @@ pub fn main() void {
     while (true) {
         switch (state) {
             .refresh => {
-                var full_path = std.ArrayList(u8).init(allocator);
+                var full_path: std.ArrayListUnmanaged(u8) = .empty;
-                defer full_path.deinit();
+                defer full_path.deinit(allocator);
-                mem_sink.global.root.?.fmtPath(true, &full_path);
+                mem_sink.global.root.?.fmtPath(allocator, true, &full_path);
-                scan.scan(util.arrayListBufZ(&full_path)) catch {
+                scan.scan(util.arrayListBufZ(&full_path, allocator)) catch {
                     sink.global.last_error = allocator.dupeZ(u8, full_path.items) catch unreachable;
                     sink.global.state = .err;
                     while (state == .refresh) handleEvent(true, true);
@@ -613,13 +604,18 @@ pub fn main() void {
                 browser.loadDir(0);
             },
             .shell => {
-                spawnShell();
+                const shell = std.posix.getenvZ("NCDU_SHELL") orelse std.posix.getenvZ("SHELL") orelse "/bin/sh";
+                var env = std.process.getEnvMap(allocator) catch unreachable;
+                defer env.deinit();
+                ui.runCmd(&.{shell}, browser.dir_path, &env, false);
                 state = .browse;
             },
             .delete => {
                 const next = delete.delete();
+                if (state != .refresh) {
                     state = .browse;
                     browser.loadDir(if (next) |n| n.nameHash() else 0);
+                }
             },
             else => handleEvent(true, false)
         }
@@ -634,14 +630,14 @@ pub fn handleEvent(block: bool, force_draw: bool) void {
     while (ui.oom_threads.load(.monotonic) > 0) ui.oom();
 
     if (block or force_draw or event_delay_timer.read() > config.update_delay) {
-        if (ui.inited) _ = ui.c.erase();
+        if (ui.inited) _ = c.erase();
         switch (state) {
             .scan, .refresh => sink.draw(),
             .browse => browser.draw(),
             .delete => delete.draw(),
             .shell => unreachable,
         }
-        if (ui.inited) _ = ui.c.refresh();
+        if (ui.inited) _ = c.refresh();
         event_delay_timer.reset();
     }
     if (!ui.inited) {
@@ -669,13 +665,13 @@ test "argument parser" {
     const T = struct {
         a: Args,
         fn opt(self: *@This(), isopt: bool, val: []const u8) !void {
-            const o = self.a.next().?;
+            const o = (self.a.next() catch unreachable).?;
             try std.testing.expectEqual(isopt, o.opt);
             try std.testing.expectEqualStrings(val, o.val);
             try std.testing.expectEqual(o.is(val), isopt);
         }
         fn arg(self: *@This(), val: []const u8) !void {
-            try std.testing.expectEqualStrings(val, self.a.arg());
+            try std.testing.expectEqualStrings(val, self.a.arg() catch unreachable);
         }
     };
     var t = T{ .a = Args.init(&lst) };

src/mem_sink.zig

@@ -17,6 +17,24 @@ pub const Thread = struct {
     arena: std.heap.ArenaAllocator = std.heap.ArenaAllocator.init(std.heap.page_allocator),
 };
 
+pub fn statToEntry(stat: *const sink.Stat, e: *model.Entry, parent: *model.Dir) void {
+    e.pack.blocks = stat.blocks;
+    e.size = stat.size;
+    if (e.dir()) |d| {
+        d.parent = parent;
+        d.pack.dev = model.devices.getId(stat.dev);
+    }
+    if (e.link()) |l| {
+        l.parent = parent;
+        l.ino = stat.ino;
+        l.pack.nlink = stat.nlink;
+        model.inodes.lock.lock();
+        defer model.inodes.lock.unlock();
+        l.addLink();
+    }
+    if (e.ext()) |ext| ext.* = stat.ext;
+}
+
 pub const Dir = struct {
     dir: *model.Dir,
     entries: Map,
@@ -107,21 +125,7 @@ pub const Dir = struct {
         }
 
         const e = self.getEntry(t, stat.etype, main.config.extended and !stat.ext.isEmpty(), name);
-        e.pack.blocks = stat.blocks;
+        statToEntry(stat, e, self.dir);
-        e.size = stat.size;
-        if (e.dir()) |d| {
-            d.parent = self.dir;
-            d.pack.dev = model.devices.getId(stat.dev);
-        }
-        if (e.link()) |l| {
-            l.parent = self.dir;
-            l.ino = stat.ino;
-            l.pack.nlink = stat.nlink;
-            model.inodes.lock.lock();
-            defer model.inodes.lock.unlock();
-            l.addLink();
-        }
-        if (e.ext()) |ext| ext.* = stat.ext;
         return e;
     }
 

src/mem_src.zig

@@ -56,14 +56,14 @@ fn rec(ctx: *Ctx, dir: *sink.Dir, entry: *model.Entry) void {
 pub fn run(d: *model.Dir) void {
     const sink_threads = sink.createThreads(1);
 
-    var ctx = .{
+    var ctx: Ctx = .{
         .sink = &sink_threads[0],
         .stat = toStat(&d.entry),
     };
-    var buf = std.ArrayList(u8).init(main.allocator);
+    var buf: std.ArrayListUnmanaged(u8) = .empty;
-    d.fmtPath(true, &buf);
+    d.fmtPath(main.allocator, true, &buf);
     const root = sink.createRoot(buf.items, &ctx.stat);
-    buf.deinit();
+    buf.deinit(main.allocator);
 
     var it = d.sub.ptr;
     while (it) |e| : (it = e.next.ptr) rec(&ctx, root, e);

src/model.zig

@@ -109,7 +109,8 @@ pub const Entry = extern struct {
     fn alloc(comptime T: type, allocator: std.mem.Allocator, etype: EType, isext: bool, ename: []const u8) *Entry {
         const size = (if (isext) @as(usize, @sizeOf(Ext)) else 0) + @sizeOf(T) + ename.len + 1;
         var ptr = blk: while (true) {
-            if (allocator.allocWithOptions(u8, size, 1, null)) |p| break :blk p
+            const alignment = if (@typeInfo(@TypeOf(std.mem.Allocator.allocWithOptions)).@"fn".params[3].type == ?u29) 1 else std.mem.Alignment.@"1";
+            if (allocator.allocWithOptions(u8, size, alignment, null)) |p| break :blk p
             else |_| {}
             ui.oom();
         };
@@ -217,19 +218,20 @@ pub const Dir = extern struct {
         suberr: bool = false,
     };
 
-    pub fn fmtPath(self: *const @This(), withRoot: bool, out: *std.ArrayList(u8)) void {
+    pub fn fmtPath(self: *const @This(), alloc: std.mem.Allocator, withRoot: bool, out: *std.ArrayListUnmanaged(u8)) void {
         if (!withRoot and self.parent == null) return;
-        var components = std.ArrayList([:0]const u8).init(main.allocator);
+        var components: std.ArrayListUnmanaged([:0]const u8) = .empty;
-        defer components.deinit();
+        defer components.deinit(main.allocator);
         var it: ?*const @This() = self;
         while (it) |e| : (it = e.parent)
             if (withRoot or e.parent != null)
-                components.append(e.entry.name()) catch unreachable;
+                components.append(main.allocator, e.entry.name()) catch unreachable;
 
         var i: usize = components.items.len-1;
         while (true) {
-            if (i != components.items.len-1 and !(out.items.len != 0 and out.items[out.items.len-1] == '/')) out.append('/') catch unreachable;
+            if (i != components.items.len-1 and !(out.items.len != 0 and out.items[out.items.len-1] == '/'))
-            out.appendSlice(components.items[i]) catch unreachable;
+                out.append(main.allocator, '/') catch unreachable;
+            out.appendSlice(alloc, components.items[i]) catch unreachable;
             if (i == 0) break;
             i -= 1;
         }
@@ -271,11 +273,11 @@ pub const Link = extern struct {
 
     // Return value should be freed with main.allocator.
     pub fn path(self: *const @This(), withRoot: bool) [:0]const u8 {
-        var out = std.ArrayList(u8).init(main.allocator);
+        var out: std.ArrayListUnmanaged(u8) = .empty;
-        self.parent.fmtPath(withRoot, &out);
+        self.parent.fmtPath(main.allocator, withRoot, &out);
-        out.append('/') catch unreachable;
+        out.append(main.allocator, '/') catch unreachable;
-        out.appendSlice(self.entry.name()) catch unreachable;
+        out.appendSlice(main.allocator, self.entry.name()) catch unreachable;
-        return out.toOwnedSliceSentinel(0) catch unreachable;
+        return out.toOwnedSliceSentinel(main.allocator, 0) catch unreachable;
     }
 
     // Add this link to the inodes map and mark it as 'uncounted'.
@@ -350,7 +352,7 @@ pub const Ext = extern struct {
 pub const devices = struct {
     var lock = std.Thread.Mutex{};
     // id -> dev
-    pub var list = std.ArrayList(u64).init(main.allocator);
+    pub var list: std.ArrayListUnmanaged(u64) = .empty;
     // dev -> id
     var lookup = std.AutoHashMap(u64, DevId).init(main.allocator);
 
@@ -361,7 +363,7 @@ pub const devices = struct {
         if (!d.found_existing) {
             if (list.items.len >= std.math.maxInt(DevId)) ui.die("Maximum number of device identifiers exceeded.\n", .{});
             d.value_ptr.* = @as(DevId, @intCast(list.items.len));
-            list.append(dev) catch unreachable;
+            list.append(main.allocator, dev) catch unreachable;
         }
         return d.value_ptr.*;
     }

src/scan.zig

@@ -8,13 +8,13 @@ const model = @import("model.zig");
 const sink = @import("sink.zig");
 const ui = @import("ui.zig");
 const exclude = @import("exclude.zig");
-const c_statfs = @cImport(@cInclude("sys/vfs.h"));
+const c = @import("c.zig").c;
 
 
 // This function only works on Linux
 fn isKernfs(dir: std.fs.Dir) bool {
-    var buf: c_statfs.struct_statfs = undefined;
+    var buf: c.struct_statfs = undefined;
-    if (c_statfs.fstatfs(dir.fd, &buf) != 0) return false; // silently ignoring errors isn't too nice.
+    if (c.fstatfs(dir.fd, &buf) != 0) return false; // silently ignoring errors isn't too nice.
     const iskern = switch (util.castTruncate(u32, buf.f_type)) {
         // These numbers are documented in the Linux 'statfs(2)' man page, so I assume they're stable.
         0x42494e4d, // BINFMTFS_MAGIC
@@ -46,14 +46,24 @@ fn truncate(comptime T: type, comptime field: anytype, x: anytype) std.meta.fiel
 }
 
 
-fn statAt(parent: std.fs.Dir, name: [:0]const u8, follow: bool, symlink: *bool) !sink.Stat {
+pub fn statAt(parent: std.fs.Dir, name: [:0]const u8, follow: bool, symlink: ?*bool) !sink.Stat {
-    const stat = try std.posix.fstatatZ(parent.fd, name, if (follow) 0 else std.posix.AT.SYMLINK_NOFOLLOW);
+    // std.posix.fstatatZ() in Zig 0.14 is not suitable due to https://github.com/ziglang/zig/issues/23463
-    symlink.* = std.posix.S.ISLNK(stat.mode);
+    var stat: std.c.Stat = undefined;
+    if (std.c.fstatat(parent.fd, name, &stat, if (follow) 0 else std.c.AT.SYMLINK_NOFOLLOW) != 0) {
+        return switch (std.c._errno().*) {
+            @intFromEnum(std.c.E.NOENT) => error.FileNotFound,
+            @intFromEnum(std.c.E.NAMETOOLONG) => error.NameTooLong,
+            @intFromEnum(std.c.E.NOMEM) => error.OutOfMemory,
+            @intFromEnum(std.c.E.ACCES) => error.AccessDenied,
+            else => error.Unexpected,
+        };
+    }
+    if (symlink) |s| s.* = std.c.S.ISLNK(stat.mode);
     return sink.Stat{
         .etype =
-            if (std.posix.S.ISDIR(stat.mode)) .dir
+            if (std.c.S.ISDIR(stat.mode)) .dir
             else if (stat.nlink > 1) .link
-            else if (!std.posix.S.ISREG(stat.mode)) .nonreg
+            else if (!std.c.S.ISREG(stat.mode)) .nonreg
             else .reg,
         .blocks = clamp(sink.Stat, .blocks, stat.blocks),
         .size = clamp(sink.Stat, .size, stat.size),
@@ -67,7 +77,7 @@ fn statAt(parent: std.fs.Dir, name: [:0]const u8, follow: bool, symlink: *bool)
                 .hasgid = true,
                 .hasmode = true,
             },
-            .mtime = clamp(model.Ext, .mtime, stat.mtime().tv_sec),
+            .mtime = clamp(model.Ext, .mtime, stat.mtime().sec),
             .uid = truncate(model.Ext, .uid, stat.uid),
             .gid = truncate(model.Ext, .gid, stat.gid),
             .mode = truncate(model.Ext, .mode, stat.mode),
@@ -81,7 +91,7 @@ fn isCacheDir(dir: std.fs.Dir) bool {
     const f = dir.openFileZ("CACHEDIR.TAG", .{}) catch return false;
     defer f.close();
     var buf: [sig.len]u8 = undefined;
-    const len = f.reader().readAll(&buf) catch return false;
+    const len = f.readAll(&buf) catch return false;
     return len == sig.len and std.mem.eql(u8, &buf, sig);
 }
 
@@ -174,7 +184,7 @@ const Thread = struct {
     thread_num: usize,
     sink: *sink.Thread,
     state: *State,
-    stack: std.ArrayList(*Dir) = std.ArrayList(*Dir).init(main.allocator),
+    stack: std.ArrayListUnmanaged(*Dir) = .empty,
     thread: std.Thread = undefined,
     namebuf: [4096]u8 = undefined,
 
@@ -255,13 +265,13 @@ const Thread = struct {
         const s = dir.sink.addDir(t.sink, name, &stat);
         const ndir = Dir.create(edir, stat.dev, dir.pat.enter(name), s);
         if (main.config.threads == 1 or !t.state.tryPush(ndir))
-            t.stack.append(ndir) catch unreachable;
+            t.stack.append(main.allocator, ndir) catch unreachable;
     }
 
     fn run(t: *Thread) void {
-        defer t.stack.deinit();
+        defer t.stack.deinit(main.allocator);
         while (t.state.waitPop()) |dir| {
-            t.stack.append(dir) catch unreachable;
+            t.stack.append(main.allocator, dir) catch unreachable;
 
             while (t.stack.items.len > 0) {
                 const d = t.stack.items[t.stack.items.len - 1];
@@ -276,7 +286,7 @@ const Thread = struct {
                 if (entry) |e| t.scanOne(d, e.name)
                 else {
                     t.sink.setDir(null);
-                    t.stack.pop().destroy(t);
+                    t.stack.pop().?.destroy(t);
                 }
             }
         }

src/sink.zig

@@ -140,20 +140,21 @@ pub const Dir = struct {
     }
 
     fn path(d: *Dir) [:0]u8 {
-        var components = std.ArrayList([]const u8).init(main.allocator);
+        var components: std.ArrayListUnmanaged([]const u8) = .empty;
-        defer components.deinit();
+        defer components.deinit(main.allocator);
         var it: ?*Dir = d;
-        while (it) |e| : (it = e.parent) components.append(e.name) catch unreachable;
+        while (it) |e| : (it = e.parent) components.append(main.allocator, e.name) catch unreachable;
 
-        var out = std.ArrayList(u8).init(main.allocator);
+        var out: std.ArrayListUnmanaged(u8) = .empty;
         var i: usize = components.items.len-1;
         while (true) {
-            if (i != components.items.len-1 and !(out.items.len != 0 and out.items[out.items.len-1] == '/')) out.append('/') catch unreachable;
+            if (i != components.items.len-1 and !(out.items.len != 0 and out.items[out.items.len-1] == '/'))
-            out.appendSlice(components.items[i]) catch unreachable;
+                out.append(main.allocator, '/') catch unreachable;
+            out.appendSlice(main.allocator, components.items[i]) catch unreachable;
             if (i == 0) break;
             i -= 1;
         }
-        return out.toOwnedSliceSentinel(0) catch unreachable;
+        return out.toOwnedSliceSentinel(main.allocator, 0) catch unreachable;
     }
 
     fn ref(d: *Dir) void {
@@ -162,7 +163,7 @@ pub const Dir = struct {
 
     pub fn unref(d: *Dir, t: *Thread) void {
         if (d.refcnt.fetchSub(1, .release) != 1) return;
-        d.refcnt.fence(.acquire);
+        _ = d.refcnt.load(.acquire);
 
         switch (d.out) {
             .mem => |*m| m.final(if (d.parent) |p| &p.out.mem else null),
@@ -291,7 +292,7 @@ fn drawConsole() void {
         var ansi: ?bool = null;
         var lines_written: usize = 0;
     };
-    const stderr = std.io.getStdErr();
+    const stderr = if (@hasDecl(std.io, "getStdErr")) std.io.getStdErr() else std.fs.File.stderr();
     const ansi = st.ansi orelse blk: {
         const t = stderr.supportsAnsiEscapeCodes();
         st.ansi = t;
@@ -450,7 +451,9 @@ pub fn draw() void {
     switch (main.config.scan_ui.?) {
         .none => {},
         .line => drawConsole(),
-        .full => switch (global.state) {
+        .full => {
+            ui.init();
+            switch (global.state) {
                 .done => {},
                 .err => drawError(),
                 .zeroing => {
@@ -469,6 +472,7 @@ pub fn draw() void {
                     }
                 },
                 .running => drawProgress(),
+            }
         },
     }
 }

src/ui.zig

@@ -6,16 +6,7 @@
 const std = @import("std");
 const main = @import("main.zig");
 const util = @import("util.zig");
-
+const c = @import("c.zig").c;
-pub const c = @cImport({
-    @cDefine("_XOPEN_SOURCE", "1");
-    @cInclude("stdio.h");
-    @cInclude("string.h");
-    @cInclude("curses.h");
-    @cInclude("time.h");
-    @cInclude("wchar.h");
-    @cInclude("locale.h");
-});
 
 pub var inited: bool = false;
 pub var main_thread: std.Thread.Id = undefined;
@@ -26,8 +17,7 @@ pub var cols: u32 = undefined;
 
 pub fn die(comptime fmt: []const u8, args: anytype) noreturn {
     deinit();
-    const stderr = std.io.getStdErr();
+    std.debug.print(fmt, args);
-    stderr.writer().print(fmt, args) catch {};
     std.process.exit(1);
 }
 
@@ -36,6 +26,8 @@ pub fn quit() noreturn {
     std.process.exit(0);
 }
 
+const sleep = if (@hasDecl(std.time, "sleep")) std.time.sleep else std.Thread.sleep;
+
 // Should be called when malloc fails. Will show a message to the user, wait
 // for a second and return to give it another try.
 // Glitch: this function may be called while we're in the process of drawing
@@ -46,18 +38,17 @@ pub fn quit() noreturn {
 // no clue if ncurses will consistently report OOM, but we're not handling that
 // right now.
 pub fn oom() void {
-    @setCold(true);
+    @branchHint(.cold);
     if (main_thread == std.Thread.getCurrentId()) {
         const haveui = inited;
         deinit();
-        const stderr = std.io.getStdErr();
+        std.debug.print("\x1b7\x1b[JOut of memory, trying again in 1 second. Hit Ctrl-C to abort.\x1b8", .{});
-        stderr.writeAll("\x1b7\x1b[JOut of memory, trying again in 1 second. Hit Ctrl-C to abort.\x1b8") catch {};
+        sleep(std.time.ns_per_s);
-        std.time.sleep(std.time.ns_per_s);
         if (haveui)
             init();
     } else {
         _ = oom_threads.fetchAdd(1, .monotonic);
-        std.time.sleep(std.time.ns_per_s);
+        sleep(std.time.ns_per_s);
         _ = oom_threads.fetchSub(1, .monotonic);
     }
 }
@@ -89,7 +80,7 @@ pub fn errorString(e: anyerror) [:0]const u8 {
     };
 }
 
-var to_utf8_buf = std.ArrayList(u8).init(main.allocator);
+var to_utf8_buf: std.ArrayListUnmanaged(u8) = .empty;
 
 fn toUtf8BadChar(ch: u8) bool {
     return switch (ch) {
@@ -116,19 +107,19 @@ pub fn toUtf8(in: [:0]const u8) [:0]const u8 {
         if (std.unicode.utf8ByteSequenceLength(in[i])) |cp_len| {
             if (!toUtf8BadChar(in[i]) and i + cp_len <= in.len) {
                 if (std.unicode.utf8Decode(in[i .. i + cp_len])) |_| {
-                    to_utf8_buf.appendSlice(in[i .. i + cp_len]) catch unreachable;
+                    to_utf8_buf.appendSlice(main.allocator, in[i .. i + cp_len]) catch unreachable;
                     i += cp_len;
                     continue;
                 } else |_| {}
             }
         } else |_| {}
-        to_utf8_buf.writer().print("\\x{X:0>2}", .{in[i]}) catch unreachable;
+        to_utf8_buf.writer(main.allocator).print("\\x{X:0>2}", .{in[i]}) catch unreachable;
         i += 1;
     }
-    return util.arrayListBufZ(&to_utf8_buf);
+    return util.arrayListBufZ(&to_utf8_buf, main.allocator);
 }
 
-var shorten_buf = std.ArrayList(u8).init(main.allocator);
+var shorten_buf: std.ArrayListUnmanaged(u8) = .empty;
 
 // Shorten the given string to fit in the given number of columns.
 // If the string is too long, only the prefix and suffix will be printed, with '...' in between.
@@ -159,8 +150,8 @@ pub fn shorten(in: [:0]const u8, max_width: u32) [:0] const u8 {
     if (total_width <= max_width) return in;
 
     shorten_buf.shrinkRetainingCapacity(0);
-    shorten_buf.appendSlice(in[0..prefix_end]) catch unreachable;
+    shorten_buf.appendSlice(main.allocator, in[0..prefix_end]) catch unreachable;
-    shorten_buf.appendSlice("...") catch unreachable;
+    shorten_buf.appendSlice(main.allocator, "...") catch unreachable;
 
     var start_width: u32 = prefix_width;
     var start_len: u32 = prefix_end;
@@ -172,11 +163,11 @@ pub fn shorten(in: [:0]const u8, max_width: u32) [:0] const u8 {
         start_width += cp_width;
         start_len += cp_len;
         if (total_width - start_width <= max_width - prefix_width - 3) {
-            shorten_buf.appendSlice(in[start_len..]) catch unreachable;
+            shorten_buf.appendSlice(main.allocator, in[start_len..]) catch unreachable;
             break;
         }
     }
-    return util.arrayListBufZ(&shorten_buf);
+    return util.arrayListBufZ(&shorten_buf, main.allocator);
 }
 
 fn shortenTest(in: [:0]const u8, max_width: u32, out: [:0]const u8) !void {
@@ -297,7 +288,7 @@ pub const Style = lbl: {
         };
     }
     break :lbl @Type(.{
-        .Enum = .{
+        .@"enum" = .{
             .tag_type = u8,
             .fields = &fields,
             .decls = &[_]std.builtin.Type.Declaration{},
@@ -344,8 +335,7 @@ fn updateSize() void {
 fn clearScr() void {
     // Send a "clear from cursor to end of screen" instruction, to clear a
     // potential line left behind from scanning in -1 mode.
-    const stderr = std.io.getStdErr();
+    std.debug.print("\x1b[J", .{});
-    stderr.writeAll("\x1b[J") catch {};
 }
 
 pub fn init() void {
@@ -428,7 +418,7 @@ pub const FmtSize = struct {
     pub fn fmt(v: u64) FmtSize {
         if (main.config.si) {
             if      (v < 1000)                    { return FmtSize.init("  B", v, 10, 1); }
-            else if (v < 999_950)                 { return FmtSize.init(" KB", v, 1, 100); }
+            else if (v < 999_950)                 { return FmtSize.init(" kB", v, 1, 100); }
             else if (v < 999_950_000)             { return FmtSize.init(" MB", v, 1, 100_000); }
             else if (v < 999_950_000_000)         { return FmtSize.init(" GB", v, 1, 100_000_000); }
             else if (v < 999_950_000_000_000)     { return FmtSize.init(" TB", v, 1, 100_000_000_000); }
@@ -461,11 +451,11 @@ test "fmtsize" {
     main.config.si = true;
     try FmtSize.fmt(            0).testEql("  0.0  B");
     try FmtSize.fmt(          999).testEql("999.0  B");
-    try FmtSize.fmt(         1000).testEql("  1.0 KB");
+    try FmtSize.fmt(         1000).testEql("  1.0 kB");
-    try FmtSize.fmt(         1049).testEql("  1.0 KB");
+    try FmtSize.fmt(         1049).testEql("  1.0 kB");
-    try FmtSize.fmt(         1050).testEql("  1.1 KB");
+    try FmtSize.fmt(         1050).testEql("  1.1 kB");
-    try FmtSize.fmt(      999_899).testEql("999.9 KB");
+    try FmtSize.fmt(      999_899).testEql("999.9 kB");
-    try FmtSize.fmt(      999_949).testEql("999.9 KB");
+    try FmtSize.fmt(      999_949).testEql("999.9 kB");
     try FmtSize.fmt(      999_950).testEql("  1.0 MB");
     try FmtSize.fmt(     1000_000).testEql("  1.0 MB");
     try FmtSize.fmt(  999_850_009).testEql("999.9 MB");
@@ -643,7 +633,7 @@ pub fn getch(block: bool) i32 {
         }
         if (ch == c.ERR) {
             if (!block) return 0;
-            std.time.sleep(10*std.time.ns_per_ms);
+            sleep(10*std.time.ns_per_ms);
             continue;
         }
         return ch;
@@ -651,3 +641,50 @@ pub fn getch(block: bool) i32 {
     die("Error reading keyboard input, assuming TTY has been lost.\n(Potentially nonsensical error message: {s})\n",
         .{ c.strerror(@intFromEnum(std.posix.errno(-1))) });
 }
+
+fn waitInput() void {
+    if (@hasDecl(std.io, "getStdIn")) {
+        std.io.getStdIn().reader().skipUntilDelimiterOrEof('\n') catch unreachable;
+    } else {
+        var buf: [512]u8 = undefined;
+        var rd = std.fs.File.stdin().reader(&buf);
+        _ = rd.interface.discardDelimiterExclusive('\n') catch unreachable;
+    }
+}
+
+pub fn runCmd(cmd: []const []const u8, cwd: ?[]const u8, env: *std.process.EnvMap, reporterr: bool) void {
+    deinit();
+    defer init();
+
+    // NCDU_LEVEL can only count to 9, keeps the implementation simple.
+    if (env.get("NCDU_LEVEL")) |l|
+        env.put("NCDU_LEVEL", if (l.len == 0) "1" else switch (l[0]) {
+            '0'...'8' => |d| &[1] u8{d+1},
+            '9' => "9",
+            else => "1"
+        }) catch unreachable
+    else
+        env.put("NCDU_LEVEL", "1") catch unreachable;
+
+    var child = std.process.Child.init(cmd, main.allocator);
+    child.cwd = cwd;
+    child.env_map = env;
+
+    const term = child.spawnAndWait() catch |e| blk: {
+        std.debug.print("Error running command: {s}\n\nPress enter to continue.\n", .{ ui.errorString(e) });
+        waitInput();
+        break :blk std.process.Child.Term{ .Exited = 0 };
+    };
+
+    const n = switch (term) {
+        .Exited  => "error",
+        .Signal  => "signal",
+        .Stopped => "stopped",
+        .Unknown => "unknown",
+    };
+    const v = switch (term) { inline else => |v| v };
+    if (term != .Exited or (reporterr and v != 0)) {
+        std.debug.print("\nCommand returned with {s} code {}.\nPress enter to continue.\n", .{ n, v });
+        waitInput();
+    }
+}

src/util.zig

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: MIT
 
 const std = @import("std");
+const c = @import("c.zig").c;
 
 // Cast any integer type to the target type, clamping the value to the supported maximum if necessary.
 pub fn castClamp(comptime T: type, x: anytype) T {
@@ -17,8 +18,8 @@ pub fn castClamp(comptime T: type, x: anytype) T {
 
 // Cast any integer type to the target type, truncating if necessary.
 pub fn castTruncate(comptime T: type, x: anytype) T {
-    const Ti = @typeInfo(T).Int;
+    const Ti = @typeInfo(T).int;
-    const Xi = @typeInfo(@TypeOf(x)).Int;
+    const Xi = @typeInfo(@TypeOf(x)).int;
     const nx: std.meta.Int(Ti.signedness, Xi.bits) = @bitCast(x);
     return if (Xi.bits > Ti.bits) @truncate(nx) else nx;
 }
@@ -31,8 +32,8 @@ pub fn blocksToSize(b: u64) u64 {
 // Ensure the given arraylist buffer gets zero-terminated and returns a slice
 // into the buffer. The returned buffer is invalidated whenever the arraylist
 // is freed or written to.
-pub fn arrayListBufZ(buf: *std.ArrayList(u8)) [:0]const u8 {
+pub fn arrayListBufZ(buf: *std.ArrayListUnmanaged(u8), alloc: std.mem.Allocator) [:0]const u8 {
-    buf.append(0) catch unreachable;
+    buf.append(alloc, 0) catch unreachable;
     defer buf.items.len -= 1;
     return buf.items[0..buf.items.len-1:0];
 }
@@ -170,3 +171,79 @@ test "strnatcmp" {
         for (i+1..w.len) |j| try eq(strnatcmp(w[i], w[j]), .lt);
     }
 }
+
+
+pub fn expanduser(path: []const u8, alloc: std.mem.Allocator) ![:0]u8 {
+    if (path.len == 0 or path[0] != '~') return alloc.dupeZ(u8, path);
+
+    const len = std.mem.indexOfScalar(u8, path, '/') orelse path.len;
+    const home_raw = blk: {
+        const pwd = pwd: {
+            if (len == 1) {
+                if (std.posix.getenvZ("HOME")) |p| break :blk p;
+                break :pwd c.getpwuid(c.getuid());
+            } else {
+                const name = try alloc.dupeZ(u8, path[1..len]);
+                defer alloc.free(name);
+                break :pwd c.getpwnam(name.ptr);
+            }
+        };
+        if (pwd != null)
+            if (@as(*c.struct_passwd, pwd).pw_dir) |p|
+                break :blk std.mem.span(p);
+        return alloc.dupeZ(u8, path);
+    };
+    const home = std.mem.trimRight(u8, home_raw, "/");
+
+    if (home.len == 0 and path.len == len) return alloc.dupeZ(u8, "/");
+    return try std.mem.concatWithSentinel(alloc, u8, &.{ home, path[len..] }, 0);
+}
+
+
+// Silly abstraction to read a file one line at a time. Only exists to help
+// with supporting both Zig 0.14 and 0.15, can be removed once 0.14 support is
+// dropped.
+pub const LineReader = if (@hasDecl(std.io, "bufferedReader")) struct {
+    rd: std.io.BufferedReader(4096, std.fs.File.Reader),
+    fbs: std.io.FixedBufferStream([]u8),
+
+    pub fn init(f: std.fs.File, buf: []u8) @This() {
+        return .{
+            .rd = std.io.bufferedReader(f.reader()),
+            .fbs = std.io.fixedBufferStream(buf),
+        };
+    }
+
+    pub fn read(s: *@This()) !?[]u8 {
+        s.fbs.reset();
+        s.rd.reader().streamUntilDelimiter(s.fbs.writer(), '\n', s.fbs.buffer.len) catch |err| switch (err) {
+            error.EndOfStream => if (s.fbs.getPos() catch unreachable == 0) return null,
+            else => |e| return e,
+        };
+        return s.fbs.getWritten();
+    }
+
+} else struct {
+    rd: std.fs.File.Reader,
+
+    pub fn init(f: std.fs.File, buf: []u8) @This() {
+        return .{ .rd = f.readerStreaming(buf) };
+    }
+
+    pub fn read(s: *@This()) !?[]u8 {
+        // Can't use takeDelimiter() because that's not available in 0.15.1,
+        // Can't use takeDelimiterExclusive() because that changed behavior in 0.15.2.
+        const r = &s.rd.interface;
+        const result = r.peekDelimiterInclusive('\n') catch |err| switch (err) {
+            error.EndOfStream => {
+                const remaining = r.buffer[r.seek..r.end];
+                if (remaining.len == 0) return null;
+                r.toss(remaining.len);
+                return remaining;
+            },
+            else => |e| return e,
+        };
+        r.toss(result.len);
+        return result[0 .. result.len - 1];
+    }
+};