MSCompressedSection::getContents() - Code Metrics - Inspection of "Allow section data greater than needed" - mlocati/chm-lib - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( 7c9391...32ff51 )

by Michele

created 2016-05-04 16:57 UTC

MSCompressedSection::getContents() C

↳ Parent: MSCompressedSection

Complexity

Conditions	15
Paths	5

Size

Total Lines	65
Code Lines	49

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	45
CRAP Score	15.0549

Importance

Changes	2
Bugs	1	Features	0

Metric	Value
c	2
b	1
f	0
dl	0
loc	65
ccs	45
cts	48
cp	0.9375
rs	5.9352
cc	15
eloc	49
nc	5
nop	2
crap	15.0549

How to fix Long Method Complexity

<?php

namespace CHMLib\Section;

use Exception;
use CHMLib\CHM;
use CHMLib\Reader\StringReader;
use CHMLib\Reader\BitReader;
use CHMLib\Header\LZXC;
use CHMLib\LZX\Inflater;
use CHMLib\LZX\LRUCache;

/**
 * Represent a LXZ-compressed section of data in a CHM file.
 */
class MSCompressedSection extends Section
{
    /**
     * The LZX reset interval.
     *
     * @var int
     */
    protected $resetInterval;

    /**
     * The window size.
     *
     * @var int
     */
    protected $windowSize;

    /**
     * The size of the uncompressed data.
     *
     * @var int
     */
    protected $uncompressedLength;

    /**
     * The size of the compressed data.
     *
     * @var int
     */
    protected $compressedLength;

    /**
     * The block size.
     *
     * @var int
     */
    protected $blockSize;

    /**
     * The address table.
     *
     * @var int[]
     */
    protected $addressTable;

    /**
     * The currently cached blocks.
     *
     * @var LRUCache
     */
    protected $cachedBlocks;

    /**
     * Initializes the instance.
     *
     * @param CHM $chm The parent CHM file.
     *
     * @throws Exception Throws an Exception in case of errors.
     */
    public function __construct(CHM $chm)
    {
        parent::__construct($chm);
        $controlDataEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/ControlData');
        if ($controlDataEntry === null) {
            throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/ControlData'");
        }
        if ($controlDataEntry->getContentSectionIndex() !== 0) {
            throw new Exception("The content of the entry '{$controlDataEntry->getPath()}' should be in section 0, but it's in section {$controlDataEntry->getContentSectionIndex()}");
        }
        $controlDataReader = new StringReader($controlDataEntry->getContents());
        $lzxc = new LZXC($controlDataReader);
        $this->resetInterval = $lzxc->getResetInterval();
        $this->windowSize = $lzxc->getWindowSize() * 32768;
        $this->cachedBlocks = new LRUCache((1 + $lzxc->getCacheSize()) << 2);
        $resetTableEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/Transform/{7FC28940-9D31-11D0-9B27-00A0C91E9C7C}/InstanceData/ResetTable');
        if ($resetTableEntry === null) {
            throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/Transform/{7FC28940-9D31-11D0-9B27-00A0C91E9C7C}/InstanceData/ResetTable'");
        }
        if ($resetTableEntry->getContentSectionIndex() !== 0) {
            throw new Exception("The content of the entry '{$resetTableEntry->getPath()}' should be in section 0, but it's in section {$resetTableEntry->getContentSectionIndex()}");
        }
        $resetTableReader = new StringReader($resetTableEntry->getContents());
        $resetTableVersion = $resetTableReader->readUInt32();
        if ($resetTableVersion !== 2) {
            throw new Exception("Unsupported LZX Reset Table version: $resetTableVersion");
        }
        $addressTableSize = $resetTableReader->readUInt32();
        /* Size of table entry (8) */ $resetTableReader->readUInt32();
        /* Header length (40) */ $resetTableReader->readUInt32();

        $this->uncompressedLength = $resetTableReader->readUInt64();
class Id
{
    public $id;

    public function __construct($id)
    {
        $this->id = $id;
    }

}

class Account
{
    /** @var  Id $id */
    public $id;
}

$account_id = false;

if (starsAreRight()) {
    $account_id = new Id(42);
}

$account = new Account();
if ($account instanceof Id)
{
    $account->id = $account_id;
}
        $this->compressedLength = $resetTableReader->readUInt64();
class Id
{
    public $id;

    public function __construct($id)
    {
        $this->id = $id;
    }

}

class Account
{
    /** @var  Id $id */
    public $id;
}

$account_id = false;

if (starsAreRight()) {
    $account_id = new Id(42);
}

$account = new Account();
if ($account instanceof Id)
{
    $account->id = $account_id;
}
        $this->blockSize = $resetTableReader->readUInt64(); // We do not support block sizes bigger than 32-bit integers
class Id
{
    public $id;

    public function __construct($id)
    {
        $this->id = $id;
    }

}

class Account
{
    /** @var  Id $id */
    public $id;
}

$account_id = false;

if (starsAreRight()) {
    $account_id = new Id(42);
}

$account = new Account();
if ($account instanceof Id)
{
    $account->id = $account_id;
}
        $this->addressTable = array();
        for ($i = 0; $i < $addressTableSize; ++$i) {
            $this->addressTable[$i] = $resetTableReader->readUInt64();
        }
        $contentEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/Content');
        if ($contentEntry === null) {
            throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/Content");
        }
        if ($this->compressedLength > $contentEntry->getLength()) {
            throw new Exception("Compressed section size should be {$this->compressedLength}, but it's {$contentEntry->getLength()}");
        }
        $this->sectionOffset = $chm->getITSF()->getContentOffset() + $contentEntry->getOffset();
    }

    /**
     * {@inheritdoc}
     *
     * @see Section::getContents()
     */
    public function getContents($offset, $length)
    {
        $result = '';
        if ($length > 0) {
            $startBlockNo = (int) ($offset / $this->blockSize);
            $startOffset = $offset % $this->blockSize;
            $endBlockNo = (int) (($offset + $length) / $this->blockSize);
            $endOffset = (int) (($offset + $length) % $this->blockSize);
            if ($endOffset === 0 && $endBlockNo > $startBlockNo) {
                $endOffset = $this->blockSize;
                --$endBlockNo;
            }
            $blockNo = $startBlockNo - $startBlockNo % $this->resetInterval;
            $inflater = new Inflater($this->windowSize);

            $buf = array();
$myVar = 'Value';
$higher = false;

if (rand(1, 6) > 3) {
    $higher = true;
} else {
    $higher = false;
}
            $pos = 0;
            $bytesLeft = 0;
            $reader = $this->chm->getReader();
            while ($bytesLeft > 0 || $blockNo <= $endBlockNo) {
                $data = '';
                while ($bytesLeft <= 0) {
                    // Read block
                    if ($blockNo > $endBlockNo) {
                        throw new Exception('Read after last data block');
                    }
                    $cacheNo = (int) ($blockNo / $this->resetInterval);
                    $cache = $this->cachedBlocks->get($cacheNo);
                    if ($cache === null) {
                        $this->cachedBlocks->prune();
                        $cache = array();
                        $resetBlockNo = $blockNo - $blockNo % $this->resetInterval;
                        for ($i = 0; $i < $this->resetInterval && $resetBlockNo + $i < count($this->addressTable); ++$i) {
                            $thisBlockNo = $resetBlockNo + $i;
                            $len = ($thisBlockNo + 1 < count($this->addressTable)) ?
                                ($this->addressTable[$thisBlockNo + 1] - $this->addressTable[$thisBlockNo])
                                :
                                ($this->compressedLength - $this->addressTable[$thisBlockNo]);
                            $reader->setPosition($this->sectionOffset + $this->addressTable[$thisBlockNo]);
                            $bitReader = new BitReader($reader->readString($len));
                            $cache[$i] = $inflater->inflate(
                                $i === 0,
                                $bitReader,
                                $this->blockSize
                            );
                        }
                        $this->cachedBlocks->put($cacheNo, $cache);
                    }
                    $data = $cache[$blockNo % $this->resetInterval];
                    // the start block has special pos value
                    $pos = ($blockNo === $startBlockNo) ? $startOffset : 0;
                    // the end block has special length
                    $bytesLeft = ($blockNo < $startBlockNo) ? 0 : (($blockNo < $endBlockNo) ? $this->blockSize : $endOffset);
                    $bytesLeft -= $pos;
                    ++$blockNo;
                }
                $togo = $bytesLeft;
                $result .= substr($data, $pos, $togo);
                $pos += $togo;
                $bytesLeft -= $togo;
            }
        }

        return $result;
    }
}


1		<?php
2
3		namespace CHMLib\Section;
4
5		use Exception;
6		use CHMLib\CHM;
7		use CHMLib\Reader\StringReader;
8		use CHMLib\Reader\BitReader;
9		use CHMLib\Header\LZXC;
10		use CHMLib\LZX\Inflater;
11		use CHMLib\LZX\LRUCache;
12
13		/**
14		* Represent a LXZ-compressed section of data in a CHM file.
15		*/
16		class MSCompressedSection extends Section
17		{
18		/**
19		* The LZX reset interval.
20		*
21		* @var int
22		*/
23		protected $resetInterval;
24
25		/**
26		* The window size.
27		*
28		* @var int
29		*/
30		protected $windowSize;
31
32		/**
33		* The size of the uncompressed data.
34		*
35		* @var int
36		*/
37		protected $uncompressedLength;
38
39		/**
40		* The size of the compressed data.
41		*
42		* @var int
43		*/
44		protected $compressedLength;
45
46		/**
47		* The block size.
48		*
49		* @var int
50		*/
51		protected $blockSize;
52
53		/**
54		* The address table.
55		*
56		* @var int[]
57		*/
58		protected $addressTable;
59
60		/**
61		* The currently cached blocks.
62		*
63		* @var LRUCache
64		*/
65		protected $cachedBlocks;
66
67		/**
68		* Initializes the instance.
69		*
70		* @param CHM $chm The parent CHM file.
71		*
72		* @throws Exception Throws an Exception in case of errors.
73		*/
74	1	public function __construct(CHM $chm)
75		{
76	1	parent::__construct($chm);
77	1	$controlDataEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/ControlData');
78	1	if ($controlDataEntry === null) {
79		throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/ControlData'");
80		}
81	1	if ($controlDataEntry->getContentSectionIndex() !== 0) {
82		throw new Exception("The content of the entry '{$controlDataEntry->getPath()}' should be in section 0, but it's in section {$controlDataEntry->getContentSectionIndex()}");
83		}
84	1	$controlDataReader = new StringReader($controlDataEntry->getContents());
85	1	$lzxc = new LZXC($controlDataReader);
86	1	$this->resetInterval = $lzxc->getResetInterval();
87	1	$this->windowSize = $lzxc->getWindowSize() * 32768;
88	1	$this->cachedBlocks = new LRUCache((1 + $lzxc->getCacheSize()) << 2);
89	1	$resetTableEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/Transform/{7FC28940-9D31-11D0-9B27-00A0C91E9C7C}/InstanceData/ResetTable');
90	1	if ($resetTableEntry === null) {
91		throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/Transform/{7FC28940-9D31-11D0-9B27-00A0C91E9C7C}/InstanceData/ResetTable'");
92		}
93	1	if ($resetTableEntry->getContentSectionIndex() !== 0) {
94		throw new Exception("The content of the entry '{$resetTableEntry->getPath()}' should be in section 0, but it's in section {$resetTableEntry->getContentSectionIndex()}");
95		}
96	1	$resetTableReader = new StringReader($resetTableEntry->getContents());
97	1	$resetTableVersion = $resetTableReader->readUInt32();
98	1	if ($resetTableVersion !== 2) {
99		throw new Exception("Unsupported LZX Reset Table version: $resetTableVersion");
100		}
101	1	$addressTableSize = $resetTableReader->readUInt32();
102	1	/* Size of table entry (8) */ $resetTableReader->readUInt32();
103	1	/* Header length (40) */ $resetTableReader->readUInt32();
		0 ignored issues – show Unused Code Comprehensibility introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report `38%` of this comment could be valid code. Did you maybe forget this after debugging? Sometimes obsolete code just ends up commented out instead of removed. In this case it is better to remove the code once you have checked you do not need it. The code might also have been commented out for debugging purposes. In this case it is vital that someone uncomments it again or your project may behave in very unexpected ways in production. This check looks for comments that seem to be mostly valid code and reports them. Loading history...
104	1	$this->uncompressedLength = $resetTableReader->readUInt64();
		0 ignored issues – show Documentation Bug introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report It seems like `$resetTableReader->readUInt64()` can also be of type `double`. However, the property `$uncompressedLength` is declared as type `integer`. Maybe add an additional type check? Our type inference engine has found a suspicous assignment of a value to a property. This check raises an issue when a value that can be of a mixed type is assigned to a property that is type hinted more strictly. For example, imagine you have a variable `$accountId` that can either hold an Id object or false (if there is no account id yet). Your code now assigns that value to the `id` property of an instance of the `Account` class. This class holds a proper account, so the id value must no longer be false. Either this assignment is in error or a type check should be added for that assignment. class Id { public $id; public function __construct($id) { $this->id = $id; } } class Account { /** @var Id $id */ public $id; } $account_id = false; if (starsAreRight()) { $account_id = new Id(42); } $account = new Account(); if ($account instanceof Id) { $account->id = $account_id; } Loading history...
105	1	$this->compressedLength = $resetTableReader->readUInt64();
		0 ignored issues – show Documentation Bug introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report It seems like `$resetTableReader->readUInt64()` can also be of type `double`. However, the property `$compressedLength` is declared as type `integer`. Maybe add an additional type check? Our type inference engine has found a suspicous assignment of a value to a property. This check raises an issue when a value that can be of a mixed type is assigned to a property that is type hinted more strictly. For example, imagine you have a variable `$accountId` that can either hold an Id object or false (if there is no account id yet). Your code now assigns that value to the `id` property of an instance of the `Account` class. This class holds a proper account, so the id value must no longer be false. Either this assignment is in error or a type check should be added for that assignment. class Id { public $id; public function __construct($id) { $this->id = $id; } } class Account { /** @var Id $id */ public $id; } $account_id = false; if (starsAreRight()) { $account_id = new Id(42); } $account = new Account(); if ($account instanceof Id) { $account->id = $account_id; } Loading history...
106	1	$this->blockSize = $resetTableReader->readUInt64(); // We do not support block sizes bigger than 32-bit integers
		0 ignored issues – show Documentation Bug introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report It seems like `$resetTableReader->readUInt64()` can also be of type `double`. However, the property `$blockSize` is declared as type `integer`. Maybe add an additional type check? Our type inference engine has found a suspicous assignment of a value to a property. This check raises an issue when a value that can be of a mixed type is assigned to a property that is type hinted more strictly. For example, imagine you have a variable `$accountId` that can either hold an Id object or false (if there is no account id yet). Your code now assigns that value to the `id` property of an instance of the `Account` class. This class holds a proper account, so the id value must no longer be false. Either this assignment is in error or a type check should be added for that assignment. class Id { public $id; public function __construct($id) { $this->id = $id; } } class Account { /** @var Id $id */ public $id; } $account_id = false; if (starsAreRight()) { $account_id = new Id(42); } $account = new Account(); if ($account instanceof Id) { $account->id = $account_id; } Loading history...
107	1	$this->addressTable = array();
108	1	for ($i = 0; $i < $addressTableSize; ++$i) {
109	1	$this->addressTable[$i] = $resetTableReader->readUInt64();
110		}
111	1	$contentEntry = $chm->getEntryByPath('::DataSpace/Storage/MSCompressed/Content');
112	1	if ($contentEntry === null) {
113		throw new Exception("Missing required entry: '::DataSpace/Storage/MSCompressed/Content");
114		}
115	1	if ($this->compressedLength > $contentEntry->getLength()) {
116		throw new Exception("Compressed section size should be {$this->compressedLength}, but it's {$contentEntry->getLength()}");
117		}
118	1	$this->sectionOffset = $chm->getITSF()->getContentOffset() + $contentEntry->getOffset();
119	1	}
120
121		/**
122		* {@inheritdoc}
123		*
124		* @see Section::getContents()
125		*/
126	464	public function getContents($offset, $length)
127		{
128	464	$result = '';
129	464	if ($length > 0) {
130	464	$startBlockNo = (int) ($offset / $this->blockSize);
131	464	$startOffset = $offset % $this->blockSize;
132	464	$endBlockNo = (int) (($offset + $length) / $this->blockSize);
133	464	$endOffset = (int) (($offset + $length) % $this->blockSize);
134	464	if ($endOffset === 0 && $endBlockNo > $startBlockNo) {
135		$endOffset = $this->blockSize;
136		--$endBlockNo;
137		}
138	464	$blockNo = $startBlockNo - $startBlockNo % $this->resetInterval;
139	464	$inflater = new Inflater($this->windowSize);
140
141	464	$buf = array();
		0 ignored issues – show Unused Code introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report `$buf` is not used, you could remove the assignment. This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently. $myVar = 'Value'; $higher = false; if (rand(1, 6) > 3) { $higher = true; } else { $higher = false; } Both the `$myVar` assignment in line 1 and the `$higher` assignment in line 2 are dead. The first because `$myVar` is never used and the second because `$higher` is always overwritten for every possible time line. Loading history...
142	464	$pos = 0;
143	464	$bytesLeft = 0;
144	464	$reader = $this->chm->getReader();
145	464	while ($bytesLeft > 0 \|\| $blockNo <= $endBlockNo) {
146	464	$data = '';
147	464	while ($bytesLeft <= 0) {
148		// Read block
149	464	if ($blockNo > $endBlockNo) {
150		throw new Exception('Read after last data block');
151		}
152	464	$cacheNo = (int) ($blockNo / $this->resetInterval);
153	464	$cache = $this->cachedBlocks->get($cacheNo);
154	464	if ($cache === null) {
155	23	$this->cachedBlocks->prune();
156	23	$cache = array();
157	23	$resetBlockNo = $blockNo - $blockNo % $this->resetInterval;
158	23	for ($i = 0; $i < $this->resetInterval && $resetBlockNo + $i < count($this->addressTable); ++$i) {
159	23	$thisBlockNo = $resetBlockNo + $i;
160	23	$len = ($thisBlockNo + 1 < count($this->addressTable)) ?
161	23	($this->addressTable[$thisBlockNo + 1] - $this->addressTable[$thisBlockNo])
162		:
163	23	($this->compressedLength - $this->addressTable[$thisBlockNo]);
164	23	$reader->setPosition($this->sectionOffset + $this->addressTable[$thisBlockNo]);
165	23	$bitReader = new BitReader($reader->readString($len));
166	23	$cache[$i] = $inflater->inflate(
167	23	$i === 0,
168		$bitReader,
169	23	$this->blockSize
170		);
171		}
172	23	$this->cachedBlocks->put($cacheNo, $cache);
173		}
174	464	$data = $cache[$blockNo % $this->resetInterval];
175		// the start block has special pos value
176	464	$pos = ($blockNo === $startBlockNo) ? $startOffset : 0;
177		// the end block has special length
178	464	$bytesLeft = ($blockNo < $startBlockNo) ? 0 : (($blockNo < $endBlockNo) ? $this->blockSize : $endOffset);
179	464	$bytesLeft -= $pos;
180	464	++$blockNo;
181		}
182	464	$togo = $bytesLeft;
183	464	$result .= substr($data, $pos, $togo);
184	464	$pos += $togo;
185	464	$bytesLeft -= $togo;
186		}
187		}
188
189	464	return $result;
190		}
191		}
192

mlocati / chm-lib

Push — master ( 7c9391...32ff51 )

MSCompressedSection::getContents() C

Complexity

Size

Duplication

Code Coverage

Importance

How to fix Long Method Complexity

Long Method

Duplication Side-by-Side

Filter issues like