Struct DecodeBudget 

pub struct DecodeBudget { /* private fields */ }

How much a stream is allowed to decompress to.

The ceiling starts at MAX_DECODED_STREAM_BYTES and is raised — never lowered — by whatever the stream dictionary declares about its own uncompressed size. Raising rather than replacing is what keeps this from rejecting files stet renders correctly today: a stream that declares nothing, or declares something small, still gets the full general allowance.

Implementations

impl DecodeBudget

pub const fn new(limit: usize) -> Self

A budget with an explicit ceiling.

pub const fn limit(&self) -> usize

The ceiling, in bytes.

pub fn for_stream(dict: &PdfDict) -> Self

Derive a budget from a stream dictionary.

Two dictionary shapes declare an uncompressed size, and a file that legitimately carries a stream larger than the general allowance will be one of them:

• An image XObject declares /Width, /Height, /BitsPerComponent and /ColorSpace, which give the raster size exactly. A 60x40 inch grand-format image at 1200 dpi is 3.46 Gpx, and as 8-bit CMYK that is a legitimate 13.8 GB stream. Refusing it would be precisely the prepress regression an earlier corpus-derived image cap already caused once.
• An embedded file declares /Params << /Size n >> (PDF 32000-1 7.11.4.2), the attachment’s uncompressed length. Attachments are only decoded when a caller explicitly asks for one by name.

Both declared values are themselves bounded — image dimensions by stet_graphics::image_limits, attachment size by the file’s own claim — so a lie is a bounded lie, which is the property the general ceiling exists to guarantee.

Trait Implementations

impl Clone for DecodeBudget

fn clone(&self) -> DecodeBudget

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DecodeBudget

impl Debug for DecodeBudget

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

Formats the value using the given formatter.

impl Default for DecodeBudget

fn default() -> Self

Returns the “default value” for a type.