pyrox.dev
1{ lib, stdenv, squashfsTools, closureInfo
2
3, fileName ? "squashfs"
4, # The root directory of the squashfs filesystem is filled with the
5 # closures of the Nix store paths listed here.
6 storeContents ? []
7 # Pseudo files to be added to squashfs image
8, pseudoFiles ? []
9, noStrip ? false
10, # Compression parameters.
11 # For zstd compression you can use "zstd -Xcompression-level 6".
12 comp ? "xz -Xdict-size 100%"
13}:
14
15let
16 pseudoFilesArgs = lib.concatMapStrings (f: ''-p "${f}" '') pseudoFiles;
17 compFlag = if comp == null then "-no-compression" else "-comp ${comp}";
18in
19stdenv.mkDerivation {
20 name = "${fileName}.img";
21 __structuredAttrs = true;
22
23 nativeBuildInputs = [ squashfsTools ];
24
25 buildCommand =
26 ''
27 closureInfo=${closureInfo { rootPaths = storeContents; }}
28
29 # Also include a manifest of the closures in a format suitable
30 # for nix-store --load-db.
31 cp $closureInfo/registration nix-path-registration
32
33 '' + lib.optionalString stdenv.buildPlatform.is32bit ''
34 # 64 cores on i686 does not work
35 # fails with FATAL ERROR: mangle2:: xz compress failed with error code 5
36 if ((NIX_BUILD_CORES > 48)); then
37 NIX_BUILD_CORES=48
38 fi
39 '' + ''
40
41 # Generate the squashfs image.
42 mksquashfs nix-path-registration $(cat $closureInfo/store-paths) $out ${pseudoFilesArgs} \
43 -no-hardlinks ${lib.optionalString noStrip "-no-strip"} -keep-as-directory -all-root -b 1048576 ${compFlag} \
44 -processors $NIX_BUILD_CORES
45 '';
46}