Struct FixedArrayPagedPrefix 

pub struct FixedArrayPagedPrefix {
    pub client_id: u8,
    pub header_addr: u64,
    pub page_init_bitmap: Vec<u8>,
    pub prefix_size: usize,
}

Parsed prefix of a paged fixed array data block.

On-disk layout (H5FA_DBLOCK_PREFIX_SIZE + checksum):

"FADB"(4) + version=0(1) + client_id(1)
+ header_addr(sizeof_addr)
+ page_init_bitmap(ceil(npages/8) bytes)
+ checksum(4)

The npages pages follow at dblk_addr + prefix_size, where prefix_size is the full size including the checksum.

Fields

client_id: u8

header_addr: u64

page_init_bitmap: Vec<u8>

Page-init bitmap, MSB-first: page p initialized iff bitmap[p / 8] & (0x80 >> (p % 8)) is non-zero.

prefix_size: usize

Total size of the prefix on disk, including the 4-byte checksum. Pages start at dblk_addr + prefix_size.

Implementations

impl FixedArrayPagedPrefix

pub fn decode( buf: &[u8], ctx: &FormatContext, npages: u64, ) -> FormatResult<Self>

Decode the prefix of a paged data block.

npages comes from the header (FixedArrayHeader::npages).

pub fn page_initialized(&self, p: usize) -> bool

Whether page p has been initialized (MSB-first bit test).

Mirrors H5VM_bit_get: bitmap[p / 8] & (0x80 >> (p % 8)).

pub fn encode(&self, ctx: &FormatContext) -> Vec<u8>

Encode the prefix of a paged data block (matches decode).

On-disk layout: `“FADB”(4) + version(1) + client_id(1)

• header_addr(sizeof_addr) + page_init_bitmap(ceil(npages/8)) + checksum(4). The returned buffer is exactly prefix_size` bytes.

Trait Implementations

impl Clone for FixedArrayPagedPrefix

fn clone(&self) -> FixedArrayPagedPrefix

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FixedArrayPagedPrefix

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for FixedArrayPagedPrefix

fn eq(&self, other: &FixedArrayPagedPrefix) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for FixedArrayPagedPrefix