Block

#include <sbio/formats/random/randfmt.hh>

struct Block

Defined in src/lib/sbio/formats/random/randfmt.hh:222

The main descriptor of a Block of data in the sbio randfmt format.

A Block consists of a Header, followed by a payload. The payload’s can be described by the relevant structs (E.g. SuperBlock, MetadataBlock, etc.). Those other structs do NOT include the Header, and are not children of the Block struct. They describe only the payload. The DataBlock does not have a specific struct to describe its payload as it is an arbitrary byte stream (which can be described by a single pointer).

The sbio randfmt has a two-layer hieararchy. There are SuperBlocks which enclose a set of sub-Blocks that contain data, metadata, config, etc. Every Block has an identifier value in its Header, and both the SuperBlock and each sub-block have their own Headers.

With byte number increasing to the right, a single SuperBlock will look like:

Immediately, following SuperBlock0, comes the next SuperBlock. The entry is optional, controlled by a feature flag, and may or may not be present. If present, it has the offsets to quickly jump to each sub-Block within the SuperBlock. There is additionally, a separate feature flag which controls the presence of a series of IndexEntry objects which, if enabled, will appear at the end of the file, and contain the offsets to quickly jump to each SuperBlock.

List of all members

Name	Kind	Owner
`hdr`	`variable`	Declared here
`valid_magic`	`function`	Declared here
`test_flag`	`function`	Declared here
`block_type`	`function`	Declared here
`block_id`	`function`	Declared here
`payload_size`	`function`	Declared here
`data`	`function`	Declared here
`data`	`function`	Declared here
`closest_block`	`function`	Declared here
`next_block`	`function`	Declared here

Public Attributes

Return	Name	Description
`Header`	`hdr`

hdr

Header hdr

Defined in src/lib/sbio/formats/random/randfmt.hh:223

Public Methods

Return	Name	Description
`SBIO_HD bool`	`valid_magic` `const` `inline`
`SBIO_HD bool`	`test_flag` `const` `inline`
`SBIO_HDBlockType`	`block_type` `const` `inline`
`SBIO_HD hd_std::uint8_t`	`block_id` `const` `inline`
`SBIO_HD hd_std::uint32_t`	`payload_size` `const` `inline`
`SBIO_HD const char *`	`data` `const` `inline`	Access the first byte of the Block’s payload.
`SBIO_HD char *`	`data` `inline`
`SBIO_HD const Block *`	`closest_block` `const` `inline`	Return the next Block (if valid).
`SBIO_HD const Block *`	`next_block` `const` `inline`	Return the next Block (if valid) at this hierarchy level.

valid_magic

const inline

inline SBIO_HD bool valid_magic() const

Defined in src/lib/sbio/formats/random/randfmt.hh:225

test_flag

const inline

inline SBIO_HD bool test_flag(FormatFlags feat) const

Defined in src/lib/sbio/formats/random/randfmt.hh:229

block_type

const inline

inline SBIO_HDBlockType block_type() const

Defined in src/lib/sbio/formats/random/randfmt.hh:233

block_id

const inline

inline SBIO_HD hd_std::uint8_t block_id() const

Defined in src/lib/sbio/formats/random/randfmt.hh:237

payload_size

const inline

inline SBIO_HD hd_std::uint32_t payload_size() const

Defined in src/lib/sbio/formats/random/randfmt.hh:239

data

const inline

inline SBIO_HD const char * data() const

Defined in src/lib/sbio/formats/random/randfmt.hh:246

Access the first byte of the Block’s payload.

Returns

A pointer to the first byte of the payload.

data

inline

inline SBIO_HD char * data()

Defined in src/lib/sbio/formats/random/randfmt.hh:249

closest_block

const inline

inline SBIO_HD const Block * closest_block() const

Defined in src/lib/sbio/formats/random/randfmt.hh:261

Return the next Block (if valid).

Alternatively, this function can be thought of as returning the next Header that will be encountered. For SuperBlocks, it will return the first sub-block inside the SuperBlock. For everything else, it is equivalent to calling next_block.

Returns

The next Block in the stream, or alternatively, the closest Header.

next_block

const inline

inline SBIO_HD const Block * next_block() const

Defined in src/lib/sbio/formats/random/randfmt.hh:291

Return the next Block (if valid) at this hierarchy level.

The sbio randfmt has two levels of the hierarchy, SuperBlocks and the contained sub-blocks. If this is a SuperBlock, this function returns the next SuperBlock. Otherwise, it returns the next sub-block. For the second case, it is equivalent to the closest_block function.

Returns

The next Block at the same level of the two-level format hierarchy.