Pumpkin-MC/Pumpkin · error · CompressionError

Error while working with Gzip compression

Error message

Error while working with Gzip compression: {0}

What it means

CompressionError variant from chunk (de)compression: the Gzip encoder/decoder returned an io error while handling the chunk payload. The offending input is the Gzip-compressed chunk data read from (or being written to) the region file; corruption or truncation of that stream surfaces here wrapped in the io error.

Solutions

1. Regenerate the affected chunk data
2. Verify the gzip stream header and integrity
3. Log the underlying io error

Example fix

// before
let raw = gzip_decode(payload).unwrap();
// after
let raw = gzip_decode(payload)
    .map_err(|e| { log::error!("gzip failure on chunk data: {e}"); e })?;

fn is_gzip_failure(e: &CompressionError) -> Option<&std::io::Error> {
    if let CompressionError::GZipError(e) = e { Some(e) } else { None }
}

match decompress_chunk(payload, Scheme::Gzip) {
    Err(CompressionError::GZipError(e)) => { log::error!("gzip: {e}"); restore_from_backup() }
    other => other?,
}

When it happens

Trigger: Reading a chunk stored with gzip compression whose payload is corrupt, truncated, or not valid gzip; or a gzip compression failure during save.

Common situations: Old region files (gzip was used in early formats) that are damaged, worlds transferred incompletely, editors writing malformed gzip blobs.

Understand the failure class

Background: "failed to read file", EACCES, ENOENT and "could not read <path>" errors: when a program can't read a file from disk — this error's family across 49 libraries.

Related errors

• Compression error
• Error while working with zlib compression
• NBT reading was cut short
• Region is invalid
• Compression scheme not recognised

AI-assisted analysis of Pumpkin-MC/Pumpkin@8d4639e25a (2026-09-09). Data as JSON: /api/errors/a16537832a73b0c2. Report an issue: GitHub.

Appendix: source

Thrown at crates/pumpkin-world/src/chunk/mod.rs:60

}

#[derive(Error, Debug)]
pub enum ChunkWritingError {
    #[error("Io error: {0}")]
    IoError(std::io::Error),
    #[error("Compression error {0}")]
    Compression(CompressionError),
    #[error("Chunk serializing error: {0}")]
    ChunkSerializingError(String),
}

#[derive(Error, Debug)]
pub enum CompressionError {
    #[error("Compression scheme not recognised")]
    UnknownCompression,
    #[error("Error while working with zlib compression: {0}")]
    ZlibError(std::io::Error),
    #[error("Error while working with Gzip compression: {0}")]
    GZipError(std::io::Error),
    #[error("Error while working with LZ4 compression: {0}")]
    LZ4Error(std::io::Error),
    #[error("Error while working with zstd compression: {0}")]
    ZstdError(std::io::Error),
}

// Clone here cause we want to clone a snapshot of the chunk so we don't block writing for too long
pub struct ChunkData {
    pub section: ChunkSections,
    /// See `https://minecraft.wiki/w/Heightmap` for more info
    pub heightmap: std::sync::Mutex<ChunkHeightmaps>,
    pub x: i32,
    pub z: i32,
    pub block_ticks: ChunkTickScheduler<&'static Block>,
    pub fluid_ticks: ChunkTickScheduler<&'static Fluid>,
    pub pending_block_entities: std::sync::Mutex<FxHashMap<BlockPos, NbtCompound>>,
    pub light_engine: std::sync::Mutex<ChunkLight>,

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