A class for reading ZIP file directories, for the purposes of upload verification. More...

Public Member Functions
	error ($code, $debugMessage)
	Throw an error, and log a debug message.
	execute ()
	Read the directory according to settings in $this.
	findOldCentralDirectory ()
	Find the location of the central directory, as would be seen by a non-ZIP64 reader.
	findZip64CentralDirectory ()
	Find the location of the central directory, as would be seen by a ZIP64-compliant reader.
	getBlock ($start, $length=null)
	Get the file contents from a given offset.
	getFileLength ()
	Get the length of the file.
	getSegment ($segIndex)
	Get a section of the file starting at position $segIndex * self::SEGSIZE, of length self::SEGSIZE.
	getStructSize ($struct)
	Get the size of a structure in bytes.
	hexDump ($s)
	Debugging helper function which dumps a string in hexdump -C format.
	readCentralDirectory ($offset, $size)
	Read the central directory at the given location.
	readEndOfCentralDirectoryRecord ()
	Read the header which is at the end of the central directory, unimaginatively called the "end of central directory record" by the ZIP spec.
	readZip64EndOfCentralDirectoryLocator ()
	Read the header called the "ZIP64 end of central directory locator".
	readZip64EndOfCentralDirectoryRecord ()
	Read the header called the "ZIP64 end of central directory record".
	testBit ($value, $bitIndex)
	Returns a bit from a given position in an integer value, converted to boolean.
	unpack ($string, $struct, $offset=0)
	Unpack a binary structure.
	unpackZip64Extra ($extraField)
	Interpret ZIP64 "extra field" data and return an associative array.
Static Public Member Functions
static	read ($fileName, $callback, $options=array())
	Read a ZIP file and call a function for each file discovered in it.
Public Attributes
	$buffer
	A segmented cache of the file contents.
	$callback
	The file data callback.
	$data
	$eocdr
	Stored headers.
	$eocdr64
	$eocdr64Locator
	$file
	The opened file resource.
	$fileLength
	The cached length of the file, or null if it has not been loaded yet.
	$fileName
	The file name.
	$zip64 = false
	The ZIP64 mode.
const	GENERAL_CD_ENCRYPTED = 13
	The index of the "general field" bit for central directory encryption.
const	GENERAL_UTF8 = 11
	The index of the "general field" bit for UTF-8 file names.
const	SEGSIZE = 16384
	The segment size for the file contents cache.
const	ZIP64_EXTRA_HEADER = 0x0001
	The "extra field" ID for ZIP64 central directory entries.
Protected Member Functions
	__construct ($fileName, $callback, $options)
	Private constructor.

Detailed Description

A class for reading ZIP file directories, for the purposes of upload verification.

Only a functional interface is provided: ZipFileReader::read(). No access is given to object instances.

Definition at line 31 of file ZipDirectoryReader.php.

Constructor & Destructor Documentation

ZipDirectoryReader::__construct	(	$	fileName,
		$	callback,
		$	options
	)		`[protected]`

Private constructor.

Definition at line 132 of file ZipDirectoryReader.php.

References $callback, $fileName, and $options.

Member Function Documentation

ZipDirectoryReader::error	(	$	code,
		$	debugMessage
	)

Throw an error, and log a debug message.

Definition at line 183 of file ZipDirectoryReader.php.

References wfDebug().

Referenced by execute(), findOldCentralDirectory(), findZip64CentralDirectory(), getBlock(), getSegment(), readCentralDirectory(), readEndOfCentralDirectoryRecord(), readZip64EndOfCentralDirectoryLocator(), readZip64EndOfCentralDirectoryRecord(), and unpack().

ZipDirectoryReader::execute ( )

Read the directory according to settings in $this.

Returns:: Status

Definition at line 146 of file ZipDirectoryReader.php.

References $size, array(), data, error(), file, findOldCentralDirectory(), findZip64CentralDirectory(), ZipDirectoryReaderError\getErrorCode(), list, Status\newFatal(), Status\newGood(), readCentralDirectory(), and readEndOfCentralDirectoryRecord().

ZipDirectoryReader::findOldCentralDirectory ( )

Find the location of the central directory, as would be seen by a non-ZIP64 reader.

Returns:: List containing offset, size and end position.

Definition at line 302 of file ZipDirectoryReader.php.

References $size, array(), and error().

Referenced by execute().

ZipDirectoryReader::findZip64CentralDirectory ( )

Find the location of the central directory, as would be seen by a ZIP64-compliant reader.

Returns:: array List containing offset, size and end position.

Definition at line 322 of file ZipDirectoryReader.php.

References $size, array(), error(), readZip64EndOfCentralDirectoryLocator(), and readZip64EndOfCentralDirectoryRecord().

Referenced by execute().

ZipDirectoryReader::getBlock	(	$	start,
		$	length = `null`
	)

Get the file contents from a given offset.

If there are not enough bytes in the file to satisfy the request, an exception will be thrown.

Parameters:

int	$start	The byte offset of the start of the block.
int	$length	The number of bytes to return. If omitted, the remainder of the file will be returned.

Returns:: string

Definition at line 503 of file ZipDirectoryReader.php.

References $fileLength, error(), getFileLength(), and getSegment().

Referenced by readCentralDirectory(), readEndOfCentralDirectoryRecord(), readZip64EndOfCentralDirectoryLocator(), and readZip64EndOfCentralDirectoryRecord().

ZipDirectoryReader::getFileLength ( )

Get the length of the file.

Definition at line 485 of file ZipDirectoryReader.php.

References file.

Referenced by getBlock(), getSegment(), readEndOfCentralDirectoryRecord(), and readZip64EndOfCentralDirectoryLocator().

ZipDirectoryReader::getSegment ( $ segIndex )

Get a section of the file starting at position $segIndex * self::SEGSIZE, of length self::SEGSIZE.

The result is cached. This is a helper function for getBlock().

If there are not enough bytes in the file to satisfy the request, the return value will be truncated. If a request is made for a segment beyond the end of the file, an empty string will be returned.

Returns:: string

Definition at line 546 of file ZipDirectoryReader.php.

References error(), file, getFileLength(), and SEGSIZE.

Referenced by getBlock().

ZipDirectoryReader::getStructSize ( $ struct )

Get the size of a structure in bytes.

See unpack() for the format of $struct.

Returns:: int

Definition at line 569 of file ZipDirectoryReader.php.

References $size, as, and list.

Referenced by readCentralDirectory(), readEndOfCentralDirectoryRecord(), readZip64EndOfCentralDirectoryLocator(), readZip64EndOfCentralDirectoryRecord(), unpack(), and unpackZip64Extra().

ZipDirectoryReader::hexDump ( $ s )

Debugging helper function which dumps a string in hexdump -C format.

Definition at line 664 of file ZipDirectoryReader.php.

References $n, $s, and print.

static ZipDirectoryReader::read	(	$	fileName,
		$	callback,
		$	options = `array()`
	)		`[static]`

Read a ZIP file and call a function for each file discovered in it.

Because this class is aimed at verification, an error is raised on suspicious or ambiguous input, instead of emulating some standard behavior.

Parameters:

string	$fileName	The archive file name
array	$callback	The callback function. It will be called for each file with a single associative array each time, with members:

name: The file name. Directories conventionally have a trailing slash.

mtime: The file modification time, in MediaWiki 14-char format

size: The uncompressed file size

Parameters:

array $options An associative array of read options, with the option name in the key. This may currently contain:

zip64: If this is set to true, then we will emulate a library with ZIP64 support, like OpenJDK 7. If it is set to false, then we will emulate a library with no knowledge of ZIP64.

NOTE: The ZIP64 code is untested and probably doesn't work. It turned out to be easier to just reject ZIP64 archive uploads, since they are likely to be very rare. Confirming safety of a ZIP64 file is fairly complex. What do you do with a file that is ambiguous and broken when read with a non-ZIP64 reader, but valid when read with a ZIP64 reader? This situation is normal for a valid ZIP64 file, and working out what non-ZIP64 readers will make of such a file is not trivial.

Returns:: Status object. The following fatal errors are defined:

zip-file-open-error: The file could not be opened.

zip-wrong-format: The file does not appear to be a ZIP file.

zip-bad: There was something wrong or ambiguous about the file data.

zip-unsupported: The ZIP file uses features which ZipDirectoryReader does not support.

The default messages for those fatal errors are written in a way that makes sense for upload verification.

If a fatal error is returned, more information about the error will be available in the debug log.

Note that the callback function may be called any number of times before a fatal error is returned. If this occurs, the data sent to the callback function should be discarded.

Definition at line 89 of file ZipDirectoryReader.php.

References $callback, $fileName, and $options.

Referenced by ZipDirectoryReaderTest\readZipAssertError(), ZipDirectoryReaderTest\readZipAssertSuccess(), and UploadBase\verifyPartialFile().

ZipDirectoryReader::readCentralDirectory	(	$	offset,
		$	size
	)

Read the central directory at the given location.

Definition at line 357 of file ZipDirectoryReader.php.

References $data, $name, $size, $time, $timestamp, array(), error(), getBlock(), getStructSize(), testBit(), unpack(), and unpackZip64Extra().

Referenced by execute().

ZipDirectoryReader::readEndOfCentralDirectoryRecord ( )

Read the header which is at the end of the central directory, unimaginatively called the "end of central directory record" by the ZIP spec.

Definition at line 193 of file ZipDirectoryReader.php.

References array(), error(), getBlock(), getFileLength(), getStructSize(), and unpack().

Referenced by execute().

ZipDirectoryReader::readZip64EndOfCentralDirectoryLocator ( )

Read the header called the "ZIP64 end of central directory locator".

An error will be raised if it does not exist.

Definition at line 239 of file ZipDirectoryReader.php.

References $data, array(), error(), getBlock(), getFileLength(), getStructSize(), and unpack().

Referenced by findZip64CentralDirectory().

ZipDirectoryReader::readZip64EndOfCentralDirectoryRecord ( )

Read the header called the "ZIP64 end of central directory record".

It may replace the regular "end of central directory record" in ZIP64 files.

Definition at line 264 of file ZipDirectoryReader.php.

References $data, array(), error(), getBlock(), getStructSize(), and unpack().

Referenced by findZip64CentralDirectory().

ZipDirectoryReader::testBit	(	$	value,
		$	bitIndex
	)

Returns a bit from a given position in an integer value, converted to boolean.

Parameters:

	$value	integer
int	$bitIndex	The index of the bit, where 0 is the LSB.

Returns:: bool

Definition at line 657 of file ZipDirectoryReader.php.

References $value.

Referenced by readCentralDirectory().

ZipDirectoryReader::unpack	(	$	string,
		$	struct,
		$	offset = `0`
	)

Unpack a binary structure.

This is like the built-in unpack() function except nicer.

Parameters:

string	$string	The binary data input
array	$struct	An associative array giving structure members and their types. In the key is the field name. The value may be either an integer, in which case the field is a little-endian unsigned integer encoded in the given number of bytes, or an array, in which case the first element of the array is the type name, and the subsequent elements are type-dependent parameters. Only one such type is defined: "string": The second array element gives the length of string. Not null terminated.
int	$offset	The offset into the string at which to start unpacking.

Exceptions:

MWException

Returns:: array Unpacked associative array. Note that large integers in the input may be represented as floating point numbers in the return value, so the use of weak comparison is advised.

Definition at line 604 of file ZipDirectoryReader.php.

References $data, $key, $size, $value, array(), as, error(), getStructSize(), and list.

Referenced by readCentralDirectory(), readEndOfCentralDirectoryRecord(), readZip64EndOfCentralDirectoryLocator(), readZip64EndOfCentralDirectoryRecord(), and unpackZip64Extra().

ZipDirectoryReader::unpackZip64Extra ( $ extraField )

Interpret ZIP64 "extra field" data and return an associative array.