www.digitalmars.com

D Programming Language 2.0

Last update Wed Apr 11 21:24:37 2012

std.zlib

Compress/decompress data using the zlib library.

References:
Wikipedia

License:
Boost License 1.0.

Authors:
Walter Bright

Source:
std/zlib.d

class ZlibException: object.Exception;
Errors throw a ZlibException.

uint adler32(uint adler, const(void)[] buf);
Compute the Adler32 checksum of the data in buf[]. adler is the starting value when computing a cumulative checksum.

uint crc32(uint crc, const(void)[] buf);
Compute the CRC32 checksum of the data in buf[]. crc is the starting value when computing a cumulative checksum.

const(void)[] compress(const(void)[] srcbuf, int level);
const(void)[] compress(const(void)[] buf);
Compresses the data in srcbuf[] using compression level level. The default value for level is 6, legal values are 1..9, with 1 being the least compression and 9 being the most. Returns the compressed data.

void[] uncompress(void[] srcbuf, size_t destlen = 0u, int winbits = 15);
Decompresses the data in srcbuf[].

Parameters:
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.

Returns:
the decompressed data.

enum HeaderFormat;
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

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

this(int level, HeaderFormat header = cast(HeaderFormat)0);
this(HeaderFormat header = cast(HeaderFormat)0);
Construct. level is the same as for D.zlib.compress(). header can be used to make a gzip compatible stream.

const(void)[] compress(const(void)[] buf);
Compress the data in buf and return the compressed data. The buffers returned from successive calls to this should be concatenated together.

void[] flush(int mode = Z_FINISH);
Compress and return any remaining data. The returned data should be appended to that returned by compress().

Parameters:
int mode 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.

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

this(uint destbufsize);
this(HeaderFormat format = cast(HeaderFormat)2);
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.