Library Reference

version 2.112.0

Internal API

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std.zlib

Compress/decompress data using thezlib library.

Examples:

If you have a small buffer you can usecompress anduncompress directly.

import std.zlib;auto src ="the quick brown fox jumps over the lazy dog\r the quick brown fox jumps over the lazy dog\r";ubyte[] dst;ubyte[] result;dst = compress(src);result =cast(ubyte[]) uncompress(dst);assert(result == src);

When the data to be compressed doesn't fit in one buffer, useCompress andUnCompress.

import std.zlib;import std.stdio;import std.conv : to;import std.algorithm.iteration : map;UnCompress decmp =new UnCompress;foreach (chunk; stdin.byChunk(4096).map!(x => decmp.uncompress(x))){    chunk.to!string.write;}

ReferencesWikipedia

License:

Boost License 1.0.

Authors:

Walter Bright

Sourcestd/zlib.d

classZlibException:object.Exception;

Errors throw a ZlibException.

uintadler32(uintadler, const(void)[]buf);

Compute the Adler-32 checksum of a buffer's worth of data.

Parameters:

uint`adler`	the starting checksum for the computation. Use 1 for a new checksum. Use the output of this function for a cumulative checksum.
const(void)[]`buf`	buffer containing input data

Returns:

Auint checksum for the provided input data and starting checksum

ubyte[]compress(const(void)[]srcbuf, intlevel); ubyte[]compress(const(void)[]srcbuf);

Compress data

Parameters:

const(void)[]`srcbuf`	buffer containing the data to compress
int`level`	compression level. Legal values are -1 .. 9, with -1 indicating the default level (6), 0 indicating no compression, 1 being the least compression and 9 being the most.

Returns:

the compressed data

void[]uncompress(const(void)[]srcbuf, size_tdestlen = 0u, intwinbits = 15);

Decompresses the data in srcbuf[].

Parameters:

const(void)[]`srcbuf`	buffer containing the compressed data.
size_t`destlen`	size of the uncompressed data. It need not be accurate, but the decompression will be faster if the exact size is supplied.
int`winbits`	the base two logarithm of the maximum window size.

Returns:

the decompressed data.

enumHeaderFormat: int;

the header format the compressed stream is wrapped in

deflate: a standard zlib header
gzip: a gzip file format header
determineFromData: used when decompressing. Try to automatically detect the stream format by looking at the data

classCompress;

Used when the data to be compressed is not all in one buffer.

this(intlevel, HeaderFormatheader = HeaderFormat.deflate); this(HeaderFormatheader = HeaderFormat.deflate);

Constructor.

Parameters:

int`level`	compression level. Legal values are 1 .. 9, with 1 being the least compression and 9 being the most. The default value is 6.
HeaderFormat`header`	sets the compression type to one of the options available inHeaderFormat. Defaults to HeaderFormat.deflate.

See Also:

compress,HeaderFormat

const(void)[]compress(const(void)[]buf);

Compress the data in buf and return the compressed data.

Parameters:

const(void)[]buf data to compress

Returns:

the compressed data. The buffers returned from successive calls to this should be concatenated together.

void[]flush(intmode = Z_FINISH);

Compress and return any remaining data. The returned data should be appended to that returned by compress().

Parameters:

intmode

one of the following:

Z_SYNC_FLUSH: Syncs up flushing to the next byte boundary. Used when more data is to be compressed later on.
Z_FULL_FLUSH: Syncs up flushing to the next byte boundary. Used when more data is to be compressed later on, and the decompressor needs to be restartable at this point.
Z_FINISH: (default) Used when finished compressing the data.

classUnCompress;

Used when the data to be decompressed is not all in one buffer.

this(uintdestbufsize); this(HeaderFormatformat = HeaderFormat.determineFromData);

Construct. destbufsize is the same as for D.zlib.uncompress().

const(void)[]uncompress(const(void)[]buf);

Decompress the data in buf and return the decompressed data. The buffers returned from successive calls to this should be concatenated together.

void[]flush();

Decompress and return any remaining data. The returned data should be appended to that returned by uncompress(). The UnCompress object cannot be used further.

@property boolempty() const;

Returns true if all input data has been decompressed and no further datacan be decompressed (inflate() returned Z_STREAM_END)

Examples:

// some random dataubyte[1024] originalData =void;// append garbage data (or don't, this works in both cases)auto compressedData =cast(ubyte[]) compress(originalData) ~cast(ubyte[])"whatever";auto decompressor =new UnCompress();auto uncompressedData = decompressor.uncompress(compressedData);assert(uncompressedData[] == originalData[],"The uncompressed and the original data differ");assert(decompressor.empty,"The UnCompressor reports not being done");

uint`crc`	the starting checksum for the computation. Use 0 for a new checksum. Use the output of this function for a cumulative checksum.
const(void)[]`buf`	buffer containing input data

Movatterモバイル変換

Library Reference

std.zlib