DiffHistoryBlob Class Reference

Diff-based history compression Requires xdiff and zlib. More...

Inherits HistoryBlob.

Collaboration diagram for DiffHistoryBlob:

Public Member Functions
	__construct ()
	__sleep ()
	__wakeup ()
	addItem ( $text)
	getItem ( $key)
	getText ()
	isHappy ()
	Helper function for compression jobs Returns true until the object is "full" and ready to be committed.
	setText ( $text)
	xdiffAdler32 ( $s)
	Compute a binary "Adler-32" checksum as defined by LibXDiff, i.e.

Public Attributes
string null	$mCompressed
	Compressed storage.
string	$mDefaultKey
	The key for getText()
array	$mDiffMap
	The diff map, see above.
array null	$mDiffs
	Array of diffs.
bool	$mFrozen = false
	True if the object is locked against further writes.
string[]	$mItems = []
	Uncompressed item cache.
int	$mMaxCount = 100
	The maximum number of text items before the object becomes sad.
int	$mMaxSize = 10_000_000
	The maximum uncompressed size before the object becomes sad Should be less than max_allowed_packet.
int	$mSize = 0
	Total uncompressed size.

Detailed Description

Diff-based history compression Requires xdiff and zlib.

WARNING: Objects of this class are serialized and permanently stored in the DB. Do not change the name or visibility of any property!

Definition at line 30 of file DiffHistoryBlob.php.

Constructor & Destructor Documentation

__construct()

DiffHistoryBlob::__construct

(

)

Definition at line 74 of file DiffHistoryBlob.php.

Member Function Documentation

__sleep()

DiffHistoryBlob::__sleep

(

)

Returns

array

Definition at line 289 of file DiffHistoryBlob.php.

References $mDefaultKey, and $mDiffs.

__wakeup()

DiffHistoryBlob::__wakeup

(

)

Definition at line 316 of file DiffHistoryBlob.php.

addItem()

DiffHistoryBlob::addItem

(

$text

)

Parameters

string

$text

Returns

string

Implements HistoryBlob.

Definition at line 84 of file DiffHistoryBlob.php.

Referenced by setText().

getItem()

DiffHistoryBlob::getItem

(

$key

)

Parameters

string

$key

Returns

string

Implements HistoryBlob.

Definition at line 99 of file DiffHistoryBlob.php.

Referenced by getText().

getText()

DiffHistoryBlob::getText

(

)

Returns

string

Implements HistoryBlob.

Definition at line 113 of file DiffHistoryBlob.php.

References getItem().

isHappy()

DiffHistoryBlob::isHappy

(

)

Helper function for compression jobs Returns true until the object is "full" and ready to be committed.

Returns

bool

Definition at line 356 of file DiffHistoryBlob.php.

References $mMaxCount.

setText()

DiffHistoryBlob::setText

(

$text

)

Parameters

string

$text

Implements HistoryBlob.

Definition at line 106 of file DiffHistoryBlob.php.

References addItem().

xdiffAdler32()

DiffHistoryBlob::xdiffAdler32

(

$s

)

Compute a binary "Adler-32" checksum as defined by LibXDiff, i.e.

with the bytes backwards and initialised with 0 instead of 1. See T36428.

Parameters

string

$s

Returns

string

Definition at line 262 of file DiffHistoryBlob.php.

Member Data Documentation

$mCompressed

string null DiffHistoryBlob::$mCompressed

Compressed storage.

Definition at line 55 of file DiffHistoryBlob.php.

$mDefaultKey

string DiffHistoryBlob::$mDefaultKey

The key for getText()

Definition at line 52 of file DiffHistoryBlob.php.

Referenced by __sleep().

$mDiffMap

array DiffHistoryBlob::$mDiffMap

The diff map, see above.

Definition at line 48 of file DiffHistoryBlob.php.

$mDiffs

array null DiffHistoryBlob::$mDiffs

Array of diffs.

If a diff D from A to B is notated D = B - A, and Z is an empty string:

         { item[map[i]] - item[map[i-1]]   where i > 0

diff[i] = { { item[map[i]] - Z where i = 0

Definition at line 45 of file DiffHistoryBlob.php.

Referenced by __sleep().

$mFrozen

bool DiffHistoryBlob::$mFrozen = false

True if the object is locked against further writes.

Definition at line 58 of file DiffHistoryBlob.php.

$mItems

string [] DiffHistoryBlob::$mItems = []

Uncompressed item cache.

Definition at line 32 of file DiffHistoryBlob.php.

$mMaxCount

int DiffHistoryBlob::$mMaxCount = 100

The maximum number of text items before the object becomes sad.

Definition at line 67 of file DiffHistoryBlob.php.

Referenced by isHappy().

$mMaxSize

int DiffHistoryBlob::$mMaxSize = 10_000_000

The maximum uncompressed size before the object becomes sad Should be less than max_allowed_packet.

Definition at line 64 of file DiffHistoryBlob.php.

$mSize

int DiffHistoryBlob::$mSize = 0

Total uncompressed size.

Definition at line 35 of file DiffHistoryBlob.php.

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The documentation for this class was generated from the following file:

• includes/historyblob/DiffHistoryBlob.php