Inflater - Code Metrics - mlocati/chm-lib - Measure and Improve Code Quality continuously with Scrutinizer

Inflater B
last analyzed 2020-03-31 15:07 UTC

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	465
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	2

Test Coverage

Coverage

72.67%

Importance

Changes

Metric	Value
wmc	52
lcom	1
cbo	2
dl	0
loc	465
ccs	125
cts	172
cp	0.7267
rs	7.44
c	0
b	0
f	0

2 Methods

Rating	Name	Duplication	Size	Complexity
B	__construct()	0	27	6
F	inflate()	0	210	46

How to fix Complexity

<?php

namespace CHMLib\LZX;

use Exception;
use CHMLib\Reader\BitReader;

/**
 * Decompressor of LXZ-compressed data.
 */
class Inflater
{
    /**
     * The smallest allowable match length.
     *
     * @var int
     */
    const MIN_MATCH = 2;

    /**
     * The number of uncompressed character types.
     *
     * @var int
     */
    const NUM_CHARS = 256;

    /**
     * Block type: verbatim.
     *
     * @var int
     */
    const BLOCKTYPE_VERBATIM = 1;

    /**
     * Block type: aligned offset.
     *
     * @var int
     */
    const BLOCKTYPE_ALIGNED = 2;

    /**
     * Block type: uncompressed.
     *
     * @var int
     */
    const BLOCKTYPE_UNCOMPRESSED = 3;

    /**
     * The number of elements in the aligned offset tree.
     *
     * @var int
     */
    const ALIGNED_NUM_ELEMENTS = 8;

    /**
     * Unknown.
     *
     * @var int
     */
    const NUM_PRIMARY_LENGTHS = 7;

    /**
     * The number of elements in the length tree.
     *
     * @var int
     */
    const NUM_SECONDARY_LENGTHS = 249;

    /**
     * The index matrix of the position slot bases.
     *
     * @var int[]
     */
    protected static $POSITION_BASE = array(
              0,       1,       2,      3,      4,      6,      8,     12,     16,     24,     32,       48,      64,      96,     128,     192,
            256,     384,     512,    768,   1024,   1536,   2048,   3072,   4096,   6144,   8192,    12288,   16384,   24576,   32768,   49152,
          65536,   98304,  131072, 196608, 262144, 393216, 524288, 655360, 786432, 917504, 1048576, 1179648, 1310720, 1441792, 1572864, 1703936,
        1835008, 1966080, 2097152,
    );

    /**
     * Number of needed bits for offset-from-base data.
     *
     * @var int
     */
    protected static $EXTRA_BITS = array(
         0,  0,  0,  0,  1,  1,  2,  2,  3,  3,  4,  4,  5,  5,  6,  6,
         7,  7,  8,  8,  9,  9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
        15, 15, 16, 16, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
        17, 17, 17,
    );

    /**
     * The size of the actual decoding window.
     *
     * @var int
     */
    protected $windowSize;

    /**
     * The actual decoding window.
     *
     * @var int[]
     */
    protected $window;

    /**
     * The current offset within the window.
     *
     * @var int
     */
    protected $windowPosition;

    /**
     * The most recent non-repeated offset (LRU offset system).
     *
     * @var int
     */
    protected $r0;

    /**
     * The second most recent non-repeated offset (LRU offset system).
     *
     * @var int
     */
    protected $r1;

    /**
     * The third most recent non-repeated offset (LRU offset system).
     *
     * @var int
     */
    protected $r2;

    /**
     * The number of main tree elements.
     *
     * @var int
     */
    protected $mainElements;

    /**
     * Decoding has already been started?
     *
     * @var bool
     */
    protected $headerRead;

    /**
     * The type of the current block.
     *
     * @var int
     */
    protected $blockType;

    /**
     * The uncompressed length of the current block.
     *
     * @var int
     */
    protected $blockLength;

    /**
     * The number of ncompressed bytes still left to decode in the current block.
     *
     * @var int
     */
    protected $remainingInBlock;

    /**
     * The number of CFDATA blocks processed.
     *
     * @var int
     */
    protected $framesRead;

    /**
     * The magic header value used for transform (0 if not encoded).
     *
     * @var int
     */
    protected $intelFilesize;

    /**
     * The current offset in transform space.
     *
     * @var int
     */
    protected $intelCurrentPosition;

    /**
     * Have we seen any translatable data yet?
     *
     * @var bool
     */
    protected $intelStarted;

    /**
     * The main Huffman tree.
     *
     * @var \CHMLib\LZX\Tree
     */
    protected $mainTree;

    /**
     * The length Huffman tree.
     *
     * @var \CHMLib\LZX\Tree
     */
    protected $lengthTree;

    /**
     * The aligned offset Huffman tree.
     *
     * @var \CHMLib\LZX\Tree
     */
    protected $alignedTree;

    /**
     * Initializes the instance.
     *
     * @param int $windowSize The window size (determines the number of window subdivisions, or "position slots"),
     *
     * @throws \Exception Throws an Exception in case of errors.
     */
    public function __construct($windowSize)
    {
        $this->windowSize = (int) $windowSize;
        if ($this->windowSize < 0x8000 || $this->windowSize > 0x200000) {
            throw new Exception("Unsupported window size: $windowSize");
        }
        $this->mainTree = new Tree(12, static::NUM_CHARS + 50 * 8);
        $this->lengthTree = new Tree(12, static::NUM_SECONDARY_LENGTHS + 1);
        $this->alignedTree = new Tree(7, static::ALIGNED_NUM_ELEMENTS);
        $this->window = array_fill(0, $this->windowSize, 0);
        $this->intelFilesize = 0;
        $numPositionSlots = 0;
        $windowSize = $this->windowSize;
        while ($windowSize > 1) {
            $windowSize >>= 1;
            $numPositionSlots += 2;
        }
        switch ($numPositionSlots) {
            case 40:
                $numPositionSlots = 42;
                break;
            case 42:
                $numPositionSlots = 50;
                break;
        }
        $this->mainElements = static::NUM_CHARS + ($numPositionSlots << 3);
    }

    /**
     * Uncompress bytes.
     *
     * @param bool $reset Reset the LXZ state?
     * @param \CHMLib\Reader\BitReader $reader The reader that provides the data.
     * @param int $numberOfBytes The number of decompressed bytes to retrieve.
     *
     * @throws \Exception Throws an Exception in case of errors.
     *
     * @return string
     */
    public function inflate($reset, BitReader $reader, $numberOfBytes)
    {
        if ($reset) {
            $this->r2 = $this->r1 = $this->r0 = 1;
            $this->headerRead = false;
            $this->framesRead = 0;
            $this->remainingInBlock = 0;
            $this->blockType = null;
            $this->intelCurrentPosition = 0;
            $this->intelStarted = false;
            $this->windowPosition = 0;
            $this->mainTree->clear();
            $this->lengthTree->clear();
        }

        if ($this->headerRead === false) {
            if ($reader->readLE(1) > 0) {
                $this->intelFilesize = ($reader->readLE(16) << 16) | $reader->readLE(16);
            }
            $this->headerRead = true;
        }

        $togo = $numberOfBytes;
        while ($togo > 0) {
            if ($this->remainingInBlock === 0) {
                if ($this->blockType === static::BLOCKTYPE_UNCOMPRESSED) {
                    if (($this->blockLength & 1) !== 0) {
                        $reader->skip(1);
                    }
                }
                $this->blockType = $reader->readLE(3);
                $this->remainingInBlock = $this->blockLength = $reader->readLE(16) << 8 | $reader->readLE(8);
                switch ($this->blockType) {
                    case static::BLOCKTYPE_ALIGNED:
                        $this->alignedTree->readAlignLengthTable($reader);
                        $this->alignedTree->makeSymbolTable();
                        /* @noinspection PhpMissingBreakStatementInspection */
                    case static::BLOCKTYPE_VERBATIM:
                        $this->mainTree->readLengthTable($reader, 0, static::NUM_CHARS);
                        $this->mainTree->readLengthTable($reader, static::NUM_CHARS, $this->mainElements);
                        $this->mainTree->makeSymbolTable();
                        if ($this->mainTree->isIntel()) {
                            $this->intelStarted = true;
                        }
                        $this->lengthTree->readLengthTable($reader, 0, static::NUM_SECONDARY_LENGTHS);
                        $this->lengthTree->makeSymbolTable();
                        break;
                    case static::BLOCKTYPE_UNCOMPRESSED:
                        $this->intelStarted = true;
                        if ($reader->ensure(16) > 16) {
                            $reader->skip(-2);
                        }
                        $this->r0 = $reader->readUInt32();
                        $this->r1 = $reader->readUInt32();
                        $this->r2 = $reader->readUInt32();
                        break;
                    default:
                        throw new Exception('Unexpected block type '.$this->blockType);
                }
            }
            while (($thisRun = $this->remainingInBlock) > 0 && $togo > 0) {
                if ($thisRun > $togo) {
                    $thisRun = $togo;
                }
                $togo -= $thisRun;
                $this->remainingInBlock -= $thisRun;
                $this->windowPosition %= $this->windowSize;
                if ($this->windowPosition + $thisRun > $this->windowSize) {
                    throw new Exception('Trying to read more that window size bytes');
                }
                if ($this->blockType === static::BLOCKTYPE_UNCOMPRESSED) {
                    $this->window = $reader->readFully($this->window, $this->windowPosition, $thisRun);
                    $this->windowPosition += $thisRun;
                } else {
                    while ($thisRun > 0) {
                        $mainElement = $this->mainTree->readHuffmanSymbol($reader);
                        if ($mainElement < static::NUM_CHARS) {
                            $this->window[$this->windowPosition++] = $mainElement;
                            --$thisRun;
                        } else {
                            $mainElement -= static::NUM_CHARS;
                            $matchLength = $mainElement & static::NUM_PRIMARY_LENGTHS;
                            if ($matchLength === static::NUM_PRIMARY_LENGTHS) {
                                $matchLength += $this->lengthTree->readHuffmanSymbol($reader);
                            }
                            $matchLength += static::MIN_MATCH;
                            $matchOffset = $mainElement >> 3;
                            switch ($matchOffset) {
                                case 0:
                                    $matchOffset = $this->r0;
                                    break;
                                case 1:
                                    $matchOffset = $this->r1;
                                    $this->r1 = $this->r0;
                                    $this->r0 = $matchOffset;
                                    break;
                                case 2:
                                    $matchOffset = $this->r2;
                                    $this->r2 = $this->r0;
                                    $this->r0 = $matchOffset;
                                    break;
                                default:
                                    switch ($this->blockType) {
                                        case static::BLOCKTYPE_VERBATIM:
                                            if ($matchOffset !== 3) {
                                                $extra = static::$EXTRA_BITS[$matchOffset];
                                                $matchOffset = static::$POSITION_BASE[$matchOffset] - 2 + $reader->readLE($extra);
                                            } else {
                                                $matchOffset = 1;
                                            }
                                            break;
                                        case static::BLOCKTYPE_ALIGNED:
                                            $extra = static::$EXTRA_BITS[$matchOffset];
                                            $matchOffset = static::$POSITION_BASE[$matchOffset] - 2;
                                            switch ($extra) {
                                                case 0:
                                                    $matchOffset = 1;
                                                    break;
                                                case 1:
                                                case 2:
                                                    // verbatim bits only
                                                    $matchOffset += $reader->readLE($extra);
                                                    break;
                                                case 3:
                                                    // aligned bits only
                                                    $matchOffset += $this->alignedTree->readHuffmanSymbol($reader);
                                                    break;
                                                default:
                                                    // verbatim and aligned bits
                                                    $extra -= 3;
                                                    $matchOffset += ($reader->readLE($extra) << 3);
                                                    $matchOffset += $this->alignedTree->readHuffmanSymbol($reader);
                                                    break;
                                            }
                                            break;
                                        default:
                                            throw new Exception('Unexpected block type ' + $this->blockType);
                                    }
                                    $this->r2 = $this->r1;
                                    $this->r1 = $this->r0;
                                    $this->r0 = $matchOffset;
                                    break;
                            }
                            $runSrc = 0;
$myVar = 'Value';
$higher = false;

if (rand(1, 6) > 3) {
    $higher = true;
} else {
    $higher = false;
}
                            $runDest = $this->windowPosition;
                            $thisRun -= $matchLength;
                            // copy any wrapped around source data
                            if ($this->windowPosition >= $matchOffset) {
                                // no wrap
                                $runSrc = $runDest - $matchOffset;
                            } else {
                                // wrap around
                                $runSrc = $runDest + ($this->windowSize - $matchOffset);
                                $copyLength = $matchOffset - $this->windowPosition;
                                if ($copyLength < $matchLength) {
                                    $matchLength -= $copyLength;
                                    $this->windowPosition += $copyLength;
                                    while ($copyLength-- > 0) {
                                        $this->window[$runDest++] = $this->window[$runSrc++];
                                    }
                                    $runSrc = 0;
                                }
                            }
                            $this->windowPosition += $matchLength;
                            // copy match data - no worries about destination wraps
                            while ($matchLength-- > 0) {
                                $this->window[$runDest++] = $this->window[$runSrc++];
                            }
                        }
                    }
                }
            }
        }

        if ($togo !== 0) {
            throw new Exception('should never happens');
        }

        $result = array_slice($this->window, ($this->windowPosition === 0 ? $this->windowSize : $this->windowPosition) - $numberOfBytes, $numberOfBytes);

        // Intel E8 decoding
        if (($this->intelFilesize !== 0)) {
            if ($this->framesRead++ < 32768) {
                if ($numberOfBytes <= 6 || $this->intelStarted === false) {
                    $this->intelCurrentPosition += $numberOfBytes;
                } else {
                    $currentPosition = $this->intelCurrentPosition;
                    $this->intelCurrentPosition += $numberOfBytes;
                    for ($i = 0; $i < $numberOfBytes - 10;) {
                        if ($result[$i++] !== 0xe8) {
                            ++$currentPosition;
                        } else {
                            $absoluteOffset = ($result[$i] & 0xff) | (($result[$i + 1] & 0xff) << 8) | (($result[$i + 2] & 0xff) << 16) | (($result[$i + 3] & 0xff) << 24);
                            if (($absoluteOffset >= -$currentPosition) && ($absoluteOffset < $this->intelFilesize)) {
                                $referenceOffset = ($absoluteOffset >= 0) ? $absoluteOffset - $currentPosition : $absoluteOffset + $this->intelFilesize;
                                $result[$i] = $referenceOffset;
                                $result[$i + 1] = $referenceOffset >> 8;
                                $result[$i + 2] = $referenceOffset >> 16;
                                $result[$i + 3] = $referenceOffset >> 24;
                            }
                            $i += 4;
                            $currentPosition += 5;
                        }
                    }
                }
            }
        }

        return implode('', array_map('chr', $result));
    }
}


1		<?php
2
3		namespace CHMLib\LZX;
4
5		use Exception;
6		use CHMLib\Reader\BitReader;
7
8		/**
9		* Decompressor of LXZ-compressed data.
10		*/
11		class Inflater
12		{
13		/**
14		* The smallest allowable match length.
15		*
16		* @var int
17		*/
18		const MIN_MATCH = 2;
19
20		/**
21		* The number of uncompressed character types.
22		*
23		* @var int
24		*/
25		const NUM_CHARS = 256;
26
27		/**
28		* Block type: verbatim.
29		*
30		* @var int
31		*/
32		const BLOCKTYPE_VERBATIM = 1;
33
34		/**
35		* Block type: aligned offset.
36		*
37		* @var int
38		*/
39		const BLOCKTYPE_ALIGNED = 2;
40
41		/**
42		* Block type: uncompressed.
43		*
44		* @var int
45		*/
46		const BLOCKTYPE_UNCOMPRESSED = 3;
47
48		/**
49		* The number of elements in the aligned offset tree.
50		*
51		* @var int
52		*/
53		const ALIGNED_NUM_ELEMENTS = 8;
54
55		/**
56		* Unknown.
57		*
58		* @var int
59		*/
60		const NUM_PRIMARY_LENGTHS = 7;
61
62		/**
63		* The number of elements in the length tree.
64		*
65		* @var int
66		*/
67		const NUM_SECONDARY_LENGTHS = 249;
68
69		/**
70		* The index matrix of the position slot bases.
71		*
72		* @var int[]
73		*/
74		protected static $POSITION_BASE = array(
75		0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
76		256, 384, 512, 768, 1024, 1536, 2048, 3072, 4096, 6144, 8192, 12288, 16384, 24576, 32768, 49152,
77		65536, 98304, 131072, 196608, 262144, 393216, 524288, 655360, 786432, 917504, 1048576, 1179648, 1310720, 1441792, 1572864, 1703936,
78		1835008, 1966080, 2097152,
79		);
80
81		/**
82		* Number of needed bits for offset-from-base data.
83		*
84		* @var int
85		*/
86		protected static $EXTRA_BITS = array(
87		0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
88		7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
89		15, 15, 16, 16, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
90		17, 17, 17,
91		);
92
93		/**
94		* The size of the actual decoding window.
95		*
96		* @var int
97		*/
98		protected $windowSize;
99
100		/**
101		* The actual decoding window.
102		*
103		* @var int[]
104		*/
105		protected $window;
106
107		/**
108		* The current offset within the window.
109		*
110		* @var int
111		*/
112		protected $windowPosition;
113
114		/**
115		* The most recent non-repeated offset (LRU offset system).
116		*
117		* @var int
118		*/
119		protected $r0;
120
121		/**
122		* The second most recent non-repeated offset (LRU offset system).
123		*
124		* @var int
125		*/
126		protected $r1;
127
128		/**
129		* The third most recent non-repeated offset (LRU offset system).
130		*
131		* @var int
132		*/
133		protected $r2;
134
135		/**
136		* The number of main tree elements.
137		*
138		* @var int
139		*/
140		protected $mainElements;
141
142		/**
143		* Decoding has already been started?
144		*
145		* @var bool
146		*/
147		protected $headerRead;
148
149		/**
150		* The type of the current block.
151		*
152		* @var int
153		*/
154		protected $blockType;
155
156		/**
157		* The uncompressed length of the current block.
158		*
159		* @var int
160		*/
161		protected $blockLength;
162
163		/**
164		* The number of ncompressed bytes still left to decode in the current block.
165		*
166		* @var int
167		*/
168		protected $remainingInBlock;
169
170		/**
171		* The number of CFDATA blocks processed.
172		*
173		* @var int
174		*/
175		protected $framesRead;
176
177		/**
178		* The magic header value used for transform (0 if not encoded).
179		*
180		* @var int
181		*/
182		protected $intelFilesize;
183
184		/**
185		* The current offset in transform space.
186		*
187		* @var int
188		*/
189		protected $intelCurrentPosition;
190
191		/**
192		* Have we seen any translatable data yet?
193		*
194		* @var bool
195		*/
196		protected $intelStarted;
197
198		/**
199		* The main Huffman tree.
200		*
201		* @var \CHMLib\LZX\Tree
202		*/
203		protected $mainTree;
204
205		/**
206		* The length Huffman tree.
207		*
208		* @var \CHMLib\LZX\Tree
209		*/
210		protected $lengthTree;
211
212		/**
213		* The aligned offset Huffman tree.
214		*
215		* @var \CHMLib\LZX\Tree
216		*/
217		protected $alignedTree;
218
219		/**
220		* Initializes the instance.
221		*
222		* @param int $windowSize The window size (determines the number of window subdivisions, or "position slots"),
223		*
224		* @throws \Exception Throws an Exception in case of errors.
225		*/
226	483	public function __construct($windowSize)
227		{
228	483	$this->windowSize = (int) $windowSize;
229	483	if ($this->windowSize < 0x8000 \|\| $this->windowSize > 0x200000) {
230		throw new Exception("Unsupported window size: $windowSize");
231		}
232	483	$this->mainTree = new Tree(12, static::NUM_CHARS + 50 * 8);
233	483	$this->lengthTree = new Tree(12, static::NUM_SECONDARY_LENGTHS + 1);
234	483	$this->alignedTree = new Tree(7, static::ALIGNED_NUM_ELEMENTS);
235	483	$this->window = array_fill(0, $this->windowSize, 0);
236	483	$this->intelFilesize = 0;
237	483	$numPositionSlots = 0;
238	483	$windowSize = $this->windowSize;
239	483	while ($windowSize > 1) {
240	483	$windowSize >>= 1;
241	483	$numPositionSlots += 2;
242		}
243		switch ($numPositionSlots) {
244	483	case 40:
245		$numPositionSlots = 42;
246		break;
247	483	case 42:
248		$numPositionSlots = 50;
249		break;
250		}
251	483	$this->mainElements = static::NUM_CHARS + ($numPositionSlots << 3);
252	483	}
253
254		/**
255		* Uncompress bytes.
256		*
257		* @param bool $reset Reset the LXZ state?
258		* @param \CHMLib\Reader\BitReader $reader The reader that provides the data.
259		* @param int $numberOfBytes The number of decompressed bytes to retrieve.
260		*
261		* @throws \Exception Throws an Exception in case of errors.
262		*
263		* @return string
264		*/
265	26	public function inflate($reset, BitReader $reader, $numberOfBytes)
266		{
267	26	if ($reset) {
268	26	$this->r2 = $this->r1 = $this->r0 = 1;
269	26	$this->headerRead = false;
270	26	$this->framesRead = 0;
271	26	$this->remainingInBlock = 0;
272	26	$this->blockType = null;
273	26	$this->intelCurrentPosition = 0;
274	26	$this->intelStarted = false;
275	26	$this->windowPosition = 0;
276	26	$this->mainTree->clear();
277	26	$this->lengthTree->clear();
278		}
279
280	26	if ($this->headerRead === false) {
281	26	if ($reader->readLE(1) > 0) {
282		$this->intelFilesize = ($reader->readLE(16) << 16) \| $reader->readLE(16);
283		}
284	26	$this->headerRead = true;
285		}
286
287	26	$togo = $numberOfBytes;
288	26	while ($togo > 0) {
289	26	if ($this->remainingInBlock === 0) {
290	26	if ($this->blockType === static::BLOCKTYPE_UNCOMPRESSED) {
291		if (($this->blockLength & 1) !== 0) {
292		$reader->skip(1);
293		}
294		}
295	26	$this->blockType = $reader->readLE(3);
296	26	$this->remainingInBlock = $this->blockLength = $reader->readLE(16) << 8 \| $reader->readLE(8);
297	26	switch ($this->blockType) {
298	26	case static::BLOCKTYPE_ALIGNED:
299	6	$this->alignedTree->readAlignLengthTable($reader);
300	6	$this->alignedTree->makeSymbolTable();
301		/* @noinspection PhpMissingBreakStatementInspection */
302	22	case static::BLOCKTYPE_VERBATIM:
303	26	$this->mainTree->readLengthTable($reader, 0, static::NUM_CHARS);
304	26	$this->mainTree->readLengthTable($reader, static::NUM_CHARS, $this->mainElements);
305	26	$this->mainTree->makeSymbolTable();
306	26	if ($this->mainTree->isIntel()) {
307	6	$this->intelStarted = true;
308		}
309	26	$this->lengthTree->readLengthTable($reader, 0, static::NUM_SECONDARY_LENGTHS);
310	26	$this->lengthTree->makeSymbolTable();
311	26	break;
312		case static::BLOCKTYPE_UNCOMPRESSED:
313		$this->intelStarted = true;
314		if ($reader->ensure(16) > 16) {
315		$reader->skip(-2);
316		}
317		$this->r0 = $reader->readUInt32();
318		$this->r1 = $reader->readUInt32();
319		$this->r2 = $reader->readUInt32();
320		break;
321		default:
322		throw new Exception('Unexpected block type '.$this->blockType);
323		}
324		}
325	26	while (($thisRun = $this->remainingInBlock) > 0 && $togo > 0) {
326	26	if ($thisRun > $togo) {
327	23	$thisRun = $togo;
328		}
329	26	$togo -= $thisRun;
330	26	$this->remainingInBlock -= $thisRun;
331	26	$this->windowPosition %= $this->windowSize;
332	26	if ($this->windowPosition + $thisRun > $this->windowSize) {
333		throw new Exception('Trying to read more that window size bytes');
334		}
335	26	if ($this->blockType === static::BLOCKTYPE_UNCOMPRESSED) {
336		$this->window = $reader->readFully($this->window, $this->windowPosition, $thisRun);
337		$this->windowPosition += $thisRun;
338		} else {
339	26	while ($thisRun > 0) {
340	26	$mainElement = $this->mainTree->readHuffmanSymbol($reader);
341	26	if ($mainElement < static::NUM_CHARS) {
342	26	$this->window[$this->windowPosition++] = $mainElement;
343	26	--$thisRun;
344		} else {
345	26	$mainElement -= static::NUM_CHARS;
346	26	$matchLength = $mainElement & static::NUM_PRIMARY_LENGTHS;
347	26	if ($matchLength === static::NUM_PRIMARY_LENGTHS) {
348	26	$matchLength += $this->lengthTree->readHuffmanSymbol($reader);
349		}
350	26	$matchLength += static::MIN_MATCH;
351	26	$matchOffset = $mainElement >> 3;
352		switch ($matchOffset) {
353	26	case 0:
354	26	$matchOffset = $this->r0;
355	26	break;
356	26	case 1:
357	26	$matchOffset = $this->r1;
358	26	$this->r1 = $this->r0;
359	26	$this->r0 = $matchOffset;
360	26	break;
361	26	case 2:
362	26	$matchOffset = $this->r2;
363	26	$this->r2 = $this->r0;
364	26	$this->r0 = $matchOffset;
365	26	break;
366		default:
367	26	switch ($this->blockType) {
368	26	case static::BLOCKTYPE_VERBATIM:
369	22	if ($matchOffset !== 3) {
370	22	$extra = static::$EXTRA_BITS[$matchOffset];
371	22	$matchOffset = static::$POSITION_BASE[$matchOffset] - 2 + $reader->readLE($extra);
372		} else {
373	21	$matchOffset = 1;
374		}
375	22	break;
376	6	case static::BLOCKTYPE_ALIGNED:
377	6	$extra = static::$EXTRA_BITS[$matchOffset];
378	6	$matchOffset = static::$POSITION_BASE[$matchOffset] - 2;
379	6	switch ($extra) {
380	6	case 0:
381	6	$matchOffset = 1;
382	6	break;
383	6	case 1:
384	6	case 2:
385		// verbatim bits only
386	6	$matchOffset += $reader->readLE($extra);
387	6	break;
388	6	case 3:
389		// aligned bits only
390	6	$matchOffset += $this->alignedTree->readHuffmanSymbol($reader);
391	6	break;
392		default:
393		// verbatim and aligned bits
394	6	$extra -= 3;
395	6	$matchOffset += ($reader->readLE($extra) << 3);
396	6	$matchOffset += $this->alignedTree->readHuffmanSymbol($reader);
397	6	break;
398		}
399	6	break;
400		default:
401		throw new Exception('Unexpected block type ' + $this->blockType);
402		}
403	26	$this->r2 = $this->r1;
404	26	$this->r1 = $this->r0;
405	26	$this->r0 = $matchOffset;
406	26	break;
407		}
408	26	$runSrc = 0;
		0 ignored issues – show Unused Code introduced 2016-05-04 14:16 UTC by Report Bug Copy Issue Report `$runSrc` 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...
409	26	$runDest = $this->windowPosition;
410	26	$thisRun -= $matchLength;
411		// copy any wrapped around source data
412	26	if ($this->windowPosition >= $matchOffset) {
413		// no wrap
414	26	$runSrc = $runDest - $matchOffset;
415		} else {
416		// wrap around
417		$runSrc = $runDest + ($this->windowSize - $matchOffset);
418		$copyLength = $matchOffset - $this->windowPosition;
419		if ($copyLength < $matchLength) {
420		$matchLength -= $copyLength;
421		$this->windowPosition += $copyLength;
422		while ($copyLength-- > 0) {
423		$this->window[$runDest++] = $this->window[$runSrc++];
424		}
425		$runSrc = 0;
426		}
427		}
428	26	$this->windowPosition += $matchLength;
429		// copy match data - no worries about destination wraps
430	26	while ($matchLength-- > 0) {
431	26	$this->window[$runDest++] = $this->window[$runSrc++];
432		}
433		}
434		}
435		}
436		}
437		}
438
439	26	if ($togo !== 0) {
440		throw new Exception('should never happens');
441		}
442
443	26	$result = array_slice($this->window, ($this->windowPosition === 0 ? $this->windowSize : $this->windowPosition) - $numberOfBytes, $numberOfBytes);
444
445		// Intel E8 decoding
446	26	if (($this->intelFilesize !== 0)) {
447		if ($this->framesRead++ < 32768) {
448		if ($numberOfBytes <= 6 \|\| $this->intelStarted === false) {
449		$this->intelCurrentPosition += $numberOfBytes;
450		} else {
451		$currentPosition = $this->intelCurrentPosition;
452		$this->intelCurrentPosition += $numberOfBytes;
453		for ($i = 0; $i < $numberOfBytes - 10;) {
454		if ($result[$i++] !== 0xe8) {
455		++$currentPosition;
456		} else {
457		$absoluteOffset = ($result[$i] & 0xff) \| (($result[$i + 1] & 0xff) << 8) \| (($result[$i + 2] & 0xff) << 16) \| (($result[$i + 3] & 0xff) << 24);
458		if (($absoluteOffset >= -$currentPosition) && ($absoluteOffset < $this->intelFilesize)) {
459		$referenceOffset = ($absoluteOffset >= 0) ? $absoluteOffset - $currentPosition : $absoluteOffset + $this->intelFilesize;
460		$result[$i] = $referenceOffset;
461		$result[$i + 1] = $referenceOffset >> 8;
462		$result[$i + 2] = $referenceOffset >> 16;
463		$result[$i + 3] = $referenceOffset >> 24;
464		}
465		$i += 4;
466		$currentPosition += 5;
467		}
468		}
469		}
470		}
471		}
472
473	26	return implode('', array_map('chr', $result));
474		}
475		}
476

mlocati / chm-lib

Inflater B last analyzed 2020-03-31 15:07 UTC

Complexity

Size/Duplication

Coupling/Cohesion

Test Coverage

Importance

2 Methods

How to fix Complexity

Complex Class

Duplication Side-by-Side

Filter issues like

Inflater B
last analyzed 2020-03-31 15:07 UTC