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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:
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.

enum HeaderFormat: 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

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

this(int level, HeaderFormat header = HeaderFormat.deflate);
this(HeaderFormat header = HeaderFormat.deflate);
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 = 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.