dicom-map 0.2.6

Memory-mapped O(1) DICOM tag dictionary
Documentation 
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//! Embedded dictionary - available with the `embedded` feature.
//!
//! The bytes of `tags.dmap` at workspace root are baked into the compiled
//! binary via `include_bytes!`. Consumers call `embedded()` to obtain an
//! already-validated [`DmapDict`] without touching the filesystem.
//!
//! The build fails if `tags.dmap` is missing - run `dmap-compile` first.

use crate::DmapDict;

// rkyv requires the archive body to be 4-byte aligned. `include_bytes!` only
// guarantees 1-byte alignment, so we wrap the data in an aligned newtype.
#[repr(C, align(4))]
struct AlignedAs<Align, Bytes: ?Sized> {
    _align: [Align; 0],
    bytes: Bytes,
}

static ALIGNED_DMAP: &AlignedAs<u32, [u8]> = &AlignedAs {
    _align: [],
    bytes: *include_bytes!(concat!(env!("CARGO_MANIFEST_DIR"), "/../tags.dmap")),
};

/// Raw bytes of the embedded dictionary, guaranteed 4-byte aligned.
pub const TAGS_DMAP: &[u8] = &ALIGNED_DMAP.bytes;

/// Returns a validated [`DmapDict`] backed by the embedded bytes. Panics if
/// the bytes are somehow malformed (they can't be, in practice - the build
/// would have produced them from the same schema).
pub fn embedded() -> DmapDict {
    DmapDict::from_static(TAGS_DMAP).expect("embedded tags.dmap is malformed")
}