Something went wrong. Try again.
What happens if I push all of nixpkgs
Something went wrong. Try again.
Nix
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110# Builds an ext4 image containing a populated /nix/store with the closure# of store paths passed in the storePaths parameter, in addition to the# contents of a directory that can be populated with commands. The# generated image is sized to only fit its contents, with the expectation# that a script resizes the filesystem at boot time.{ pkgs, lib, # List of derivations to be included storePaths, # Whether or not to compress the resulting image with zstd compressImage ? false, zstd, # Shell commands to populate the ./files directory. # All files in that directory are copied to the root of the FS. populateImageCommands ? "", volumeLabel, uuid ? "44444444-4444-4444-8888-888888888888", e2fsprogs, libfaketime, perl, fakeroot,}:
let sdClosureInfo = pkgs.buildPackages.closureInfo { rootPaths = storePaths; };inpkgs.stdenv.mkDerivation { name = "ext4-fs.img${lib.optionalString compressImage ".zst"}";
nativeBuildInputs = [ e2fsprogs.bin libfaketime perl fakeroot ] ++ lib.optional compressImage zstd;
buildCommand = '' ${if compressImage then "img=temp.img" else "img=$out"} ( mkdir -p ./files ${populateImageCommands} )
echo "Preparing store paths for image..."
# Create nix/store before copying path mkdir -p ./rootImage/nix/store
xargs -I % cp -a --reflink=auto % -t ./rootImage/nix/store/ < ${sdClosureInfo}/store-paths ( GLOBIGNORE=".:.." shopt -u dotglob
for f in ./files/*; do cp -a --reflink=auto -t ./rootImage/ "$f" done )
# Also include a manifest of the closures in a format suitable for nix-store --load-db cp ${sdClosureInfo}/registration ./rootImage/nix-path-registration
# Make a crude approximation of the size of the target image. # If the script starts failing, increase the fudge factors here. numInodes=$(find ./rootImage | wc -l) numDataBlocks=$(du -s -c -B 4096 --apparent-size ./rootImage | tail -1 | awk '{ print int($1 * 1.20) }') bytes=$((2 * 4096 * $numInodes + 4096 * $numDataBlocks)) echo "Creating an EXT4 image of $bytes bytes (numInodes=$numInodes, numDataBlocks=$numDataBlocks)"
mebibyte=$(( 1024 * 1024 )) # Round up to the nearest mebibyte. # This ensures whole 512 bytes sector sizes in the disk image # and helps towards aligning partitions optimally. if (( bytes % mebibyte )); then bytes=$(( ( bytes / mebibyte + 1) * mebibyte )) fi
truncate -s $bytes $img
faketime -f "1970-01-01 00:00:01" fakeroot mkfs.ext4 -L ${volumeLabel} -U ${uuid} -d ./rootImage $img
export EXT2FS_NO_MTAB_OK=yes # I have ended up with corrupted images sometimes, I suspect that happens when the build machine's disk gets full during the build. if ! fsck.ext4 -n -f $img; then echo "--- Fsck failed for EXT4 image of $bytes bytes (numInodes=$numInodes, numDataBlocks=$numDataBlocks) ---" cat errorlog return 1 fi
# We may want to shrink the file system and resize the image to # get rid of the unnecessary slack here--but see # https://github.com/NixOS/nixpkgs/issues/125121 for caveats.
# shrink to fit resize2fs -M $img
# Add 16 MebiByte to the current_size new_size=$(dumpe2fs -h $img | awk -F: \ '/Block count/{count=$2} /Block size/{size=$2} END{print (count*size+16*2**20)/size}')
resize2fs $img $new_size
if [ ${builtins.toString compressImage} ]; then echo "Compressing image" zstd -T$NIX_BUILD_CORES -v --no-progress ./$img -o $out fi '';}