Crate datacard_rs 

DataCard: Generic Binary Card Format Library

DataCard provides a generic binary card format for storing payloads with self-describing metadata and optional CRC32 checksums.

Generic Card System

Implementors define their own card formats by implementing CardFormat:

use datacard_rs::{CardFormat, GenericCard, CardError};

pub struct TernsigFormat;

impl CardFormat for TernsigFormat {
    const MAGIC: [u8; 4] = *b"TERN";
    const VERSION_MAJOR: u8 = 1;
    const VERSION_MINOR: u8 = 0;

    fn format_name() -> &'static str { "Ternsig" }
}

// Create and use cards
let card: GenericCard<TernsigFormat> = GenericCard::new("program", payload);
card.save("program.card")?;

let loaded: GenericCard<TernsigFormat> = GenericCard::load("program.card")?;

Format Structure

┌────────────────────────────────┐
│ Header (8 bytes)               │
│   - Magic (4 bytes)            │
│   - Version (2 bytes)          │
│   - Flags (2 bytes)            │
├────────────────────────────────┤
│ Metadata (JSON, length-prefix) │
├────────────────────────────────┤
│ Payload (raw bytes)            │
├────────────────────────────────┤
│ Footer (4 bytes, optional)     │
│   - CRC32 checksum             │
└────────────────────────────────┘

Modules

checksum

CRC32 checksum utilities for DataCard

Structs

CardDeprecated

A DataCard: BytePunch-compressed CML document with metadata

CardHeader

Card file header (8 bytes)

CardMetadataDeprecated

Card metadata (stored as JSON)

GenericCard

Generic card that works with any CardFormat

GenericHeader

Generic card header (8 bytes)

GenericMetadata

Generic card metadata (JSON-serializable)

Enums

CardError

Error types for DataCard operations

Constants

FLAG_HAS_CHECKSUM

Flag: Card has CRC32 checksum in footer

FLAG_HAS_TIMESTAMP

Flag: Metadata includes timestamp

MAGIC

Magic bytes for card files (“CARD”)

VERSION_MAJOR

Current major version

VERSION_MINOR

Current minor version

Traits

CardFormat

Trait for defining card formats

Type Aliases

Result