XZ API Reference Overview

The xz package exports top-level compression and decompression functions, streaming engines, integrity check algorithms, container format components, and error sets.

Import the package:

const xz = @import("xz");

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Top-Level Functions

xz.compress

pub fn compress(allocator: std.mem.Allocator, src: []const u8, options: CompressOptions) ![]u8

Compresses src into a newly allocated slice containing a complete .xz stream.

• Parameters:
  • allocator: Memory allocator for the output slice.
  • src: Uncompressed input bytes.
  • options: Compression options (check, enable_bcj_x86, delta_distance, lzma2_options).
• Returns: Owned slice containing the valid XZ file. Must be freed by caller using allocator.free().
• Errors: OutOfMemory, InvalidOptions, OutputTooSmall.

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xz.decompress

pub fn decompress(allocator: std.mem.Allocator, src: []const u8, options: DecompressOptions) ![]u8

Decompresses an .xz container stream src into a newly allocated slice.

• Parameters:
  • allocator: Memory allocator for the output slice.
  • src: Complete XZ container bytes.
  • options: Decompression parameters (max_output_size, dict_size_limit).
• Returns: Owned slice containing restored bytes. Must be freed by caller using allocator.free().
• Errors: OutOfMemory, InvalidMagic, ChecksumMismatch, CorruptData, ExceededSizeLimit, UnsupportedFilter.

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xz.compressInto

pub fn compressInto(dst: []u8, src: []const u8, options: CompressOptions) !usize

Compresses src directly into caller-provided buffer dst with zero heap allocations.

• Returns: The number of bytes written to dst.
• Errors: OutputTooSmall.

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xz.decompressInto

pub fn decompressInto(dst: []u8, src: []const u8, options: DecompressOptions) !usize

Decompresses src directly into caller-provided buffer dst with zero heap allocations.

• Returns: The number of bytes written to dst.
• Errors: OutputTooSmall, InvalidMagic, ChecksumMismatch, CorruptData.

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xz.compressStream

pub fn compressStream(reader: anytype, writer: anytype, options: CompressOptions) !void

Incrementally reads uncompressed data from reader and writes XZ container blocks to writer.

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xz.decompressStream

pub fn decompressStream(reader: anytype, writer: anytype, options: DecompressOptions) !void

Incrementally reads an XZ container stream from reader and writes decompressed data to writer.

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xz.isXzStream

pub fn isXzStream(data: []const u8) bool

Returns true if data begins with the 6-byte XZ header magic FD 37 7A 58 5A 00.

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Submodule Exports

• xz.checksum: Checksum routines (crc32, crc64, sha256).
• xz.filters: Filter IDs (FILTER_LZMA2, FILTER_DELTA, FILTER_X86_BCJ) and state structures.
• xz.stream_header: Stream header parsing and serialization.
• xz.stream_footer: Stream footer validation and backward size calculations.
• xz.block_header: Block header flags, sizes, filter chains, and CRC32.
• xz.index: Index records, VLI serialization, padding, and CRC32.
• xz.vli: Variable-Length Integer encoders and decoders.
• xz.errors: Comprehensive error definitions.