zflate

This unit allows you to easily compress and decompress buffers and strings like in PHP. Main goal of this unit is to be as small as possible.

• compiled demo is ~80 kB in size
• adding unit to uses section increases binary size by ~45 kB, even less if you already use zlib units for other things

Status

Compression	Decompression
Function Format Status gzdeflate() DEFLATE ✔ gzcompress() ZLIB ✔ gzencode() GZIP ✔	Function Format Status gzinflate() DEFLATE ✔ gzuncompress() ZLIB ✔ gzdecode() GZIP ✔ zdecompress() ANY ✔

Usage

compressed := gzencode('some string');
decompressed := gzdecode(compressed);

Use zdecompress() to auto detect stream type and decompress:

compressed := gzencode('some string');
decompressed := zdecompress(compressed);

Functions

//compress whole buffer to DEFLATE at once
function gzdeflate(data: pointer; size: dword; var output: pointer; var outputsize: dword; level: dword=9): boolean;
//compress whole string to DEFLATE at once
function gzdeflate(str: string; level: dword=9): string;
//decompress whole DEFLATE buffer at once
function gzinflate(data: pointer; size: dword; var output: pointer; var outputsize: dword): boolean;
//decompress whole DEFLATE string at once
function gzinflate(str: string): string;

//compress whole buffer to ZLIB at once
function gzcompress(data: pointer; size: dword; var output: pointer; var outputsize: dword; level: dword=9): boolean;
//compress whole string to ZLIB at once
function gzcompress(str: string; level: dword=9): string;
//dempress whole ZLIB buffer at once
function gzuncompress(data: pointer; size: dword; var output: pointer; var outputsize: dword): boolean;
//dempress whole ZLIB string at once
function gzuncompress(str: string): string;

//compress whole buffer to GZIP at once
function gzencode(data: pointer; size: dword; var output: pointer; var outputsize: dword; level: dword=9; filename: string=''; comment: string=''): boolean;
//compress whole string to GZIP at once
function gzencode(str: string; level: dword=9; filename: string=''; comment: string=''): string;
//decompress whole GZIP buffer at once
function gzdecode(data: pointer; size: dword; var output: pointer; var outputsize: dword): boolean;
//decompress whole GZIP string at once
function gzdecode(str: string): string;

//try to detect buffer format and decompress it at once
function zdecompress(data: pointer; size: dword; var output: pointer; var outputsize: dword): boolean;
//try to detect string format and decompress it at once
function zdecompress(str: string): string;

zflatefiles

Additional unit to handle bigger files. Read & write & compress/decompress by chunks.

Status

Compression	Decompression
Function Format Status gzdeflate_file() DEFLATE ❌ gzcompress_file() ZLIB ❌ gzencode_file() GZIP ✔	Function Format Status gzinflate_file() DEFLATE ❌ gzuncompress_file() ZLIB ❌ gzdecode_file() GZIP ✔

Functions

//compress a file to GZIP
function gzencode_file(src, dst: string; level: dword=9; filename: string=''; comment: string=''; progresscb: tzprogresscb=nil; resolution: dword=100): boolean;
//decompress a GZIP file
function gzdecode_file(src, dst: string; progresscb: tzprogresscb=nil; resolution: dword=100): boolean;  

A callback may be provided to these functions. Callback function may abort ongoing operation by returning false.