README

PHP Extension providing XZ (LZMA2) compression/decompression functions (see Implement lzma (xz?) compression).

Installation

The recommended way to install the extension is using PIE:

pie install codemasher/php-ext-xz

Windows builds are now done automatically; you can download them from the releases. Copy the dll file into the /ext directory of your PHP installation and add the line extension=xz-1.x.x-8.5-ts-vs17-x86_64 to your php.ini (whatever the filename may be, you may omit the leading "php_" and the extension), see also: Loading an extension in the PHP manual.

You can check if the extension is loaded via phpinfo(), or from within PHP via:

if(!extension_loaded('xz')){
	throw new Exception('ext-xz not loaded!');
}

// ...continue to do stuff with ext-xz...

Basic usage

String-based operations

You can easily compress and decompress strings.

$string = 'This is a test string that will be compressed and then decompressed.';

// Compress a string
$compressed = xzencode($string);

// Decompress a string
$decompressed = xzdecode($compressed);

File-based operations

The extension also supports stream-based operations for working with .xz files.

$file = '/tmp/test.xz';

// Writing to an .xz file
$wh = xzopen($file, 'w');
xzwrite($wh, 'Data to write');
xzclose($wh);

// Reading from an .xz file and outputting its contents
$rh = xzopen($file, 'r');
xzpassthru($rh);
xzclose($rh);

Configuration

You can configure the default compression level and memory limit:

; Default compression level. Affects `xzencode` and `xzopen`, 
; but only when the level was not specified. Values 0-9, default is 5.
xz.compression_level=5

; The maximum amount of memory that can be used when decompressing. Default is 0 (no limit).
xz.max_memory=65536

Alternatively, the compression level can be supplied as a parameter to the xzencode() and xzopen() functions:

const COMPRESSION_LEVEL = 7;

$compressed = xzencode($string, COMPRESSION_LEVEL);

$wh = xzopen($file, 'w', COMPRESSION_LEVEL);

Build from source

Linux

This module requires liblzma-dev (https://tukaani.org/xz/) as well as php7-dev or php8-dev. If you are using Ubuntu, you can easily install all of them by typing the following command in your terminal:

sudo apt-get install git php7.4-dev liblzma-dev

To build and install as module, perform the following steps:

git clone https://github.com/codemasher/php-ext-xz.git
cd php-ext-xz
phpize
./configure
make
sudo make install

Do not forget to add extension=xz.so to your php.ini.

Windows

If you want to build it on your own, follow the steps under "Build your own PHP on Windows" to setup your build environment. Before the compilation step, clone this repository to [...]\php-src\ext\xz and proceed.

git clone https://github.com/Microsoft/php-sdk-binary-tools.git c:\php-sdk
cd c:\php-sdk
phpsdk-vs16-x64.bat

Run the buildtree script and check out the php source:

phpsdk_buildtree php-8.0
git clone https://github.com/php/php-src.git
cd php-src
git checkout PHP-8.0

Clone the xz extension and run the build:

git clone https://github.com/codemasher/php-ext-xz .\ext\xz
phpsdk_deps -u
buildconf --force
configure --enable-xz
nmake snap

Please note that the liblzma dependency is not included with PHP < 8, so you will need to download it manually and extract it into the deps directory.

Disclaimer

May or may not contain bugs. Use at your own risk.