Struct Decompress

pub struct Decompress { /* private fields */ }

Available on crate feature zlib only.

Raw in-memory decompression stream for blocks of data.

This type is the building block for the I/O streams in the rest of this crate. It requires more management than the Read/Write API but is maximally flexible in terms of accepting input from any source and being able to produce output to any memory location.

It is recommended to use the I/O stream adaptors over this type as they’re easier to use.

Implementations

impl Decompress

pub fn new(zlib_header: bool) -> Decompress

Creates a new object ready for decompressing data that it’s given.

The zlib_header argument indicates whether the input data is expected to have a zlib header or not.

pub fn new_with_window_bits(zlib_header: bool, window_bits: u8) -> Decompress

Available on crate feature any_zlib only.

Creates a new object ready for decompressing data that it’s given.

The zlib_header argument indicates whether the input data is expected to have a zlib header or not. The window_bits parameter indicates the base-2 logarithm of the sliding window size and must be between 9 and 15.

Panics

If window_bits does not fall into the range 9 ..= 15, new_with_window_bits will panic.

pub fn new_gzip(window_bits: u8) -> Decompress

Available on crate feature any_zlib only.

Creates a new object ready for decompressing data that it’s given.

The Decompress object produced by this constructor expects gzip headers for the compressed data.

Panics

If window_bits does not fall into the range 9 ..= 15, new_with_window_bits will panic.

pub fn total_in(&self) -> u64

Returns the total number of input bytes which have been processed by this decompression object.

pub fn total_out(&self) -> u64

Returns the total number of output bytes which have been produced by this decompression object.

pub fn decompress( &mut self, input: &[u8], output: &mut [u8], flush: FlushDecompress, ) -> Result<Status, DecompressError>

Decompresses the input data into the output, consuming only as much input as needed and writing as much output as possible.

The flush option can be any of the available FlushDecompress parameters.

If the first call passes FlushDecompress::Finish it is assumed that the input and output buffers are both sized large enough to decompress the entire stream in a single call.

A flush value of FlushDecompress::Finish indicates that there are no more source bytes available beside what’s already in the input buffer, and the output buffer is large enough to hold the rest of the decompressed data.

To learn how much data was consumed or how much output was produced, use the total_in and total_out functions before/after this is called.

Errors

If the input data to this instance of Decompress is not a valid zlib/deflate stream then this function may return an instance of DecompressError to indicate that the stream of input bytes is corrupted.

pub fn decompress_vec( &mut self, input: &[u8], output: &mut Vec<u8>, flush: FlushDecompress, ) -> Result<Status, DecompressError>

Decompresses the input data into the extra space in the output vector specified by output.

This function has the same semantics as decompress, except that the length of vec is managed by this function. This will not reallocate the vector provided or attempt to grow it, so space for the output must be reserved in the output vector by the caller before calling this function.

Errors

If the input data to this instance of Decompress is not a valid zlib/deflate stream then this function may return an instance of DecompressError to indicate that the stream of input bytes is corrupted.

pub fn set_dictionary( &mut self, dictionary: &[u8], ) -> Result<u32, DecompressError>

Available on crate feature any_zlib only.

Specifies the decompression dictionary to use.

pub fn reset(&mut self, zlib_header: bool)

Performs the equivalent of replacing this decompression state with a freshly allocated copy.

This function may not allocate memory, though, and attempts to reuse any previously existing resources.

The argument provided here indicates whether the reset state will attempt to decode a zlib header first or not.

Trait Implementations

impl Debug for Decompress

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

Formats the value using the given formatter.