Type Alias ZSTD_DStream 

pub type ZSTD_DStream = ZSTD_DCtx;

Port of ZSTD_DStream. Upstream typedef ZSTD_DCtx ZSTD_DStream — same struct for both APIs.

Aliased Type

pub struct ZSTD_DStream {

    pub hufTable: Vec<u32>,
    pub workspace: Vec<u32>,
    pub litExtraBuffer: Vec<u8>,
    pub litBuffer_offset: usize,
    pub litBufferEnd_offset: usize,
    pub litBufferLocation: ZSTD_litLocation_e,
    pub litPtr_offset: usize,
    pub litPtr_from_dst: bool,
    pub litSize: usize,
    pub litEntropy: u32,
    pub dictID: u32,
    pub ddict_rep: [u32; 3],
    pub previousDstEnd: Option<usize>,
    pub prefixStart: Option<usize>,
    pub virtualStart: Option<usize>,
    pub dictEnd: Option<usize>,
    pub isFrameDecompression: i32,
    pub blockSizeMax: usize,
    pub disableHufAsm: i32,
    pub bmi2: i32,
    pub ddictIsCold: i32,
    pub LLTable: Vec<ZSTD_seqSymbol>,
    pub OFTable: Vec<ZSTD_seqSymbol>,
    pub MLTable: Vec<ZSTD_seqSymbol>,
    pub ll_default_active: bool,
    pub of_default_active: bool,
    pub ml_default_active: bool,
    pub fseEntropy: u32,
    pub fse_ll_fresh: bool,
    pub fse_of_fresh: bool,
    pub fse_ml_fresh: bool,
    pub stream_in_buffer: Vec<u8>,
    pub stream_out_buffer: Vec<u8>,
    pub stream_out_drained: usize,
    pub oversizedDuration: usize,
    pub stream_dict: Vec<u8>,
    pub historyBuffer: Vec<u8>,
    pub d_windowLogMax: u32,
    pub format: ZSTD_format_e,
    pub expected: usize,
    pub stage: ZSTD_dStage,
    pub processedCSize: u64,
    pub decodedSize: u64,
    pub fParams: ZSTD_FrameHeader,
    pub bType: blockType_e,
    pub validateChecksum: u32,
    pub xxhState: XXH64_state_t,
    pub headerBuffer: [u8; 18],
    pub headerSize: usize,
    pub rleSize: usize,
    pub dictUses: ZSTD_dictUses_e,
    pub customMem: ZSTD_customMem,
}

Fields

hufTable: Vec<u32>

Huffman decoding table, sized for HUF_TABLELOG_MAX.

workspace: Vec<u32>

Scratch space for HUF_read*DTable*_wksp.

litExtraBuffer: Vec<u8>

Literal-buffer scratch; owned when litBufferLocation == ZSTD_not_in_dst.

litBuffer_offset: usize

Pointer-equivalent into litExtraBuffer or dst (as a byte index plus a tag). A real port will use an enum over &mut [u8] slices once DCtx lifetimes are settled.

litBufferEnd_offset: usize

litBufferLocation: ZSTD_litLocation_e

litPtr_offset: usize

litPtr_from_dst: bool

litSize: usize

litEntropy: u32

dictID: u32

Upstream dctx->dictID. Parsed from a zstd-format dict’s 4-byte ID field when one is loaded; 0 for raw-content dicts.

ddict_rep: [u32; 3]

Upstream dctx->ddict_rep[ZSTD_REP_NUM]. Rep values parsed from a zstd-format dict’s trailing 12-byte rep section.

previousDstEnd: Option<usize>

End pointer-equivalent of the prior decode/insert destination.

prefixStart: Option<usize>

Start pointer-equivalent of the current history segment.

virtualStart: Option<usize>

Virtual start pointer-equivalent spanning the current segment plus the immediately-previous contiguous one.

dictEnd: Option<usize>

End pointer-equivalent of the previous segment once continuity is broken and it becomes an external dictionary.

isFrameDecompression: i32

isFrameDecompression toggles ZSTD_blockSizeMax behaviour; for standalone block decode (our current scope) it’s 0.

blockSizeMax: usize

Most fParams fields are unused in the literal-block decode; keep just the block-size cap we read in frame mode.

disableHufAsm: i32

bmi2: i32

ddictIsCold: i32

LLTable: Vec<ZSTD_seqSymbol>

OFTable: Vec<ZSTD_seqSymbol>

MLTable: Vec<ZSTD_seqSymbol>

ll_default_active: bool

of_default_active: bool

ml_default_active: bool

fseEntropy: u32

fse_ll_fresh: bool

1 if the last sequences block had its FSE tables fresh (set_compressed) — gates set_repeat validity for the next block of the same type. Upstream tracks this as a bitmask inside dctx->fseEntropy; here we keep it as three independent flags.

fse_of_fresh: bool

fse_ml_fresh: bool

stream_in_buffer: Vec<u8>

Pending compressed bytes staged by ZSTD_decompressStream.

stream_out_buffer: Vec<u8>

Decoded output awaiting drain into the caller’s output buffer.

stream_out_drained: usize

Bytes already drained from stream_out_buffer into the caller.

oversizedDuration: usize

Upstream oversizedDuration: number of consecutive streaming calls whose retained buffers are much larger than the needed input/output workspace.

stream_dict: Vec<u8>

Raw-content dict set by ZSTD_initDStream_usingDict — applied to every frame decoded until reset / re-init.

historyBuffer: Vec<u8>

Sliding history of prior-block output, retained across ZSTD_decompressContinue calls so back-references in later blocks can resolve into earlier-block bytes that no longer live in the caller’s dst. Capped at fParams.windowSize (or ZSTD_BLOCKSIZE_MAX before a frame header has been parsed). Reset on frame boundaries and on ZSTD_decompressBegin.

d_windowLogMax: u32

ZSTD_d_windowLogMax: upper bound on the window size the decoder will accept. Set via ZSTD_DCtx_setParameter.

format: ZSTD_format_e

Upstream dctx->format. Selected decoder format — zstd1 (with magic) or zstd1_magicless (for embedded / streaming contexts where the 4-byte magic is known redundantly).

expected: usize

Legacy decompressContinue() expected compressed-byte count for the next state-machine transition.

stage: ZSTD_dStage

Legacy block/frame decode stage.

processedCSize: u64

Running compressed bytes consumed by the legacy continue API.

decodedSize: u64

Running decompressed bytes produced for the current frame.

fParams: ZSTD_FrameHeader

Frame header decoded for the current frame.

bType: blockType_e

Block type latched from the most recent block header.

validateChecksum: u32

Whether to validate the checksum trailer for the current frame.

xxhState: XXH64_state_t

XXH64 state for checksum validation in the legacy continue API.

headerBuffer: [u8; 18]

Full frame/skippable header bytes staged across split calls.

headerSize: usize

Full header size expected for headerBuffer.

rleSize: usize

Current RLE block’s regenerated size.

dictUses: ZSTD_dictUses_e

Upstream dctx->dictUses (zstd_decompress_internal.h:97). Tracks the dict lifecycle: ZSTD_dont_use = no dict attached; ZSTD_use_once = refPrefix-bound dict that auto-clears after one frame; ZSTD_use_indefinitely = persistent dict from loadDictionary / refDDict.

customMem: ZSTD_customMem

Upstream custom allocator bundle requested for this DCtx.