BitManipulation::intToBinaryString() - Code Metrics - Inspection of "Refacto pack" - Nekland/Woketo - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Pull Request — master (#118)

by Charlotte

created 2017-07-27 21:38 UTC

BitManipulation::intToBinaryString() B

↳ Parent: BitManipulation

Complexity

Conditions	6
Paths	10

Size

Total Lines	26
Code Lines	17

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	0
CRAP Score	42

Importance

Changes

Metric	Value
dl	0
loc	26
ccs	0
cts	22
cp	0
rs	8.439
c	0
b	0
f	0
cc	6
eloc	17
nc	10
nop	2
crap	42

<?php

/**
 * This file is a part of Woketo package.
 *
 * (c) Nekland <[email protected]>
 *
 * For the full license, take a look to the LICENSE file
 * on the root directory of this project
 */
declare(strict_types=1);

namespace Nekland\Woketo\Utils;
use Nekland\Woketo\Exception\Utils\NotLongEnoughException;

/**
 * Class BitManipulation
 *
 * Glossary:
 *   - in this context a "frame" is an assembly of bytes represented by a "byte-string" or a (signed) int.
 */
class BitManipulation
{
    /**
     * Mode from to is the default mode of inspection of frames. But PHP usually uses from and length to inspect frames.
     */
    const MODE_FROM_TO = 0;
    const MODE_PHP = 1;

    /**
     * Get a specific bit from a byte.
     *
     * @param int $byte
     * @param int $bitNumber
     * @return int
     */
    public static function nthBit(int $byte, int $bitNumber) : int
    {
        if ($byte < 0 || $byte > 255) {
            throw new \InvalidArgumentException(
                \sprintf('The given integer %s is not a byte.', $byte)
            );
        }

        if ($bitNumber < 1 || $bitNumber > 8) {
            throw new \InvalidArgumentException(
                \sprintf('The bit number %s is not a correct value for a byte (1-8 required).', $bitNumber)
            );
        }

        $realNth = \pow(2, 8 - $bitNumber);

        return (int) ($realNth === ($byte & $realNth));
    }

    /**
     * Get a specific byte inside a frame represented by an int or a string.
     *
     * @param string|int $frame      Non utf8 string (this should be more precisely a bytes-string).
     * @param int        $byteNumber Starting at 0.
     * @return int
     */
    public static function nthByte($frame, int $byteNumber) : int
    {
        if (\is_string($frame)) {
            $len = BitManipulation::frameSize($frame);

            if ($byteNumber < 0 || $byteNumber > ($len-1)) {
                throw new \InvalidArgumentException(
                    \sprintf('The frame is only %s bytes larges but you tried to get the %sth byte.', $len, $byteNumber)
                );
            }

            return \ord($frame[$byteNumber]);
        }

        if (\is_int($frame)) {
            if ($frame < 0) {
                throw new \InvalidArgumentException(
                    \sprintf('This method does not support negative ints as parameter for now. %s given.', $byteNumber)
                );
            }
            $hex = \dechex($frame);
            $len = BitManipulation::frameSize($hex);

            // Index of the first octal of the wanted byte
            $realByteNth = $byteNumber * 2;

            if ($byteNumber < 0 || ($realByteNth + 1) > $len) {
                throw new \InvalidArgumentException(
                    \sprintf('Impossible to get the byte %s from the frame %s.', $byteNumber, $frame)
                );
            }

            // Considering FF12AB (number) if you want the byte represented by AB you need to get the
            // first letter, shift it of 4 and add the next letter.
            // This may seems weird but that's because you read numbers from right to left.
            return (\hexdec($hex[$realByteNth]) << 4) + \hexdec($hex[$realByteNth + 1]);
            // _Notice that if the number is from right to left, your data is still from left to right_
        }

        throw new \InvalidArgumentException(
            \sprintf('The frame must be an int or string, %s given.', gettype($frame))
        );
    }

    public static function partOfByte(int $byte, int $part) : int
    {
        if ($byte < 0 || $byte > 255) {
            throw new \InvalidArgumentException(sprintf('%s is not a byte', $byte));
        }

        if ($part === 1) {
            return ($byte & 240) >> 4;
        }

        if ($part === 2) {
            return $byte & 15;
        }

        throw new \InvalidArgumentException(sprintf('A byte have only 2 parts. %s asked.', $part));
    }

    /**
     * Because strings are the best way to store many bytes in PHP it can
     * be useful to make the conversion between hex (which are strings)
     * array to string.
     *
     * @param array $hexArray
     * @return string
     */
    public static function hexArrayToString(...$hexArray) : string
    {
        if (\is_array($hexArray[0])) {
            $hexArray = $hexArray[0];
        }
        
        $res = '';
        foreach ($hexArray as $hexNum) {
            $res .= \chr(\hexdec($hexNum));
        }

        return $res;
    }

    /**
     * @param string|int $frame
     * @param int        $from        Byte where to start (should be inferior to $to).
     * @param int        $to          Byte where to stop (considering it starts at 0). The `to` value include the target
     *                                byte.
     * @param bool       $force8bytes By default PHP have a wrong behavior with 8 bytes variables. If you have 8 bytes
     *                                the returned int will be negative (because unsigned integers does not exists in PHP)
     * @return int
     */
    public static function bytesFromTo($frame, int $from, int $to, bool $force8bytes = false) : int
    {
        // No more than 64b (which return negative number when the first bit is specified)
        if (($to - $from) > 7 && (!$force8bytes && ($to - $from) !== 8)) {
            if ($force8bytes) {
                throw new \InvalidArgumentException(sprintf('Not more than 8 bytes (64bit) is supported by this method and you asked for %s bytes.', $to - $from));
            }
            throw new \InvalidArgumentException('PHP limitation: getting more than 7 bytes will return a negative number because unsigned int does not exist.');
        }

        if (\is_string($frame)) {
            if ((BitManipulation::frameSize($frame) - 1) < $to) {
                throw new NotLongEnoughException('The frame is not long enough.');
            }

            $subStringLength = $to - $from + 1;
            // Getting responsible bytes
            $subString = \substr($frame, $from, $subStringLength);
            $res = 0;

            // for each byte, getting ord
            for($i = 0; $i < $subStringLength; $i++) {
                $res <<= 8;
                $res += \ord($subString[$i]);
            }

            return $res;
        }

        if (!\is_int($frame)) {
            throw new \InvalidArgumentException(
                \sprintf('A frame can only be a string or int. %s given', gettype($frame))
            );
        }

        if ($frame < 0) {
            throw new \InvalidArgumentException('The frame cannot be a negative number');
        }

        $res = 0;
        for ($i = $from; $i <= $to; $i++) {
            $res <<= 8;
            $res += BitManipulation::nthByte($frame, $i);
        }

        return $res;
    }

    /**
     * Proxy to the substr to be sure to be use the right method (mb_substr)
     *
     * @param string $frame
     * @param int    $from
     * @param int    $to
     * @return string
     */
    public static function bytesFromToString(string $frame, int $from, int $to, int $mode = BitManipulation::MODE_FROM_TO) : string
    {
        if ($mode === BitManipulation::MODE_FROM_TO) {
            return \mb_substr($frame, $from, $to - $from + 1, '8bit');
        }

        return \mb_substr($frame, $from, $to, '8bit');
    }

    /**
     * Take a frame represented by a decimal int to transform it in a string.
     * Notice that any int is a frame and cannot be more than 8 bytes
     *
     * @param int      $frame
     * @param int|null $size  In bytes. This value should always be precise. Be careful if you don't !
     * @return string
     */
    public static function intToBinaryString(int $frame, int $size = null) : string
    {
        $format = 'J*';

        if ($size !== null) {
            switch (true) {
                case $size <= 2:
                    $format = 'n*';
                    break;
                case $size <= 4:
                    $format = 'N*';
                    break;
                case $size > 4:
                    $format = 'J*';
                    break;
            }
        }

        $res = pack($format, $frame);

        if ($size === null) {
            $res = ltrim($res, "\0");
        }

        return $res;
    }

    /**
     * Take an string frame and transform it to a decimal frame (inside an int).
     *
     * @param string $frame
     * @return int
     */
    public static function binaryToInt(string $frame) : int
    {
        $len = BitManipulation::frameSize($frame);

        if ($len > 8) {
            throw new \InvalidArgumentException(
                \sprintf('The string %s cannot be converted to int because an int cannot be more than 8 bytes (64b).', $frame)
            );
        }

        switch(true) {
            case $len <= 2:
                $format = 'n';
                break;
            case $len <= 4:
                $format = 'N';
                break;
            case $len > 4:
                $format = 'J';
                break;
        }

        return unpack($format, $frame)[1];
function myFunction($a) {
    switch ($a) {
        case 'foo':
            $x = 1;
            break;

        case 'bar':
            $x = 2;
            break;
    }

    // $x is potentially undefined here.
    echo $x;
}
    }

    /**
     * Method that return frame as hex (more readable).
     * Helpful for debug !
     *
     * @param string $frame
     * @return string
     */
    public static function binaryToHex(string $frame) : string
    {
        return unpack('H*', $frame)[1];
    }

    /**
     * Haters gonna hate. `strlen` cannot be trusted because of an option of mbstring extension, more info:
     * http://php.net/manual/fr/mbstring.overload.php
     * http://php.net/manual/fr/function.mb-strlen.php#77040
     *
     * @param string $frame
     * @return int
     */
    public static function frameSize(string $frame) : int
    {
        if (\extension_loaded('mbstring')) {
            return \mb_strlen($frame, '8bit');
        }

        return \strlen($frame);
    }
}


1			<?php
2
3			/**
4			* This file is a part of Woketo package.
5			*
6			* (c) Nekland <[email protected]>
7			*
8			* For the full license, take a look to the LICENSE file
9			* on the root directory of this project
10			*/
11			declare(strict_types=1);
12
13			namespace Nekland\Woketo\Utils;
14			use Nekland\Woketo\Exception\Utils\NotLongEnoughException;
15
16			/**
17			* Class BitManipulation
18			*
19			* Glossary:
20			* - in this context a "frame" is an assembly of bytes represented by a "byte-string" or a (signed) int.
21			*/
22			class BitManipulation
23			{
24			/**
25			* Mode from to is the default mode of inspection of frames. But PHP usually uses from and length to inspect frames.
26			*/
27			const MODE_FROM_TO = 0;
28			const MODE_PHP = 1;
29
30			/**
31			* Get a specific bit from a byte.
32			*
33			* @param int $byte
34			* @param int $bitNumber
35			* @return int
36			*/
37			public static function nthBit(int $byte, int $bitNumber) : int
38			{
39			if ($byte < 0 \|\| $byte > 255) {
40			throw new \InvalidArgumentException(
41			\sprintf('The given integer %s is not a byte.', $byte)
42			);
43			}
44
45			if ($bitNumber < 1 \|\| $bitNumber > 8) {
46			throw new \InvalidArgumentException(
47			\sprintf('The bit number %s is not a correct value for a byte (1-8 required).', $bitNumber)
48			);
49			}
50
51			$realNth = \pow(2, 8 - $bitNumber);
52
53			return (int) ($realNth === ($byte & $realNth));
54			}
55
56			/**
57			* Get a specific byte inside a frame represented by an int or a string.
58			*
59			* @param string\|int $frame Non utf8 string (this should be more precisely a bytes-string).
60			* @param int $byteNumber Starting at 0.
61			* @return int
62			*/
63			public static function nthByte($frame, int $byteNumber) : int
64			{
65			if (\is_string($frame)) {
66			$len = BitManipulation::frameSize($frame);
67
68			if ($byteNumber < 0 \|\| $byteNumber > ($len-1)) {
69			throw new \InvalidArgumentException(
70			\sprintf('The frame is only %s bytes larges but you tried to get the %sth byte.', $len, $byteNumber)
71			);
72			}
73
74			return \ord($frame[$byteNumber]);
75			}
76
77			if (\is_int($frame)) {
78			if ($frame < 0) {
79			throw new \InvalidArgumentException(
80			\sprintf('This method does not support negative ints as parameter for now. %s given.', $byteNumber)
81			);
82			}
83			$hex = \dechex($frame);
84			$len = BitManipulation::frameSize($hex);
85
86			// Index of the first octal of the wanted byte
87			$realByteNth = $byteNumber * 2;
88
89			if ($byteNumber < 0 \|\| ($realByteNth + 1) > $len) {
90			throw new \InvalidArgumentException(
91			\sprintf('Impossible to get the byte %s from the frame %s.', $byteNumber, $frame)
92			);
93			}
94
95			// Considering FF12AB (number) if you want the byte represented by AB you need to get the
96			// first letter, shift it of 4 and add the next letter.
97			// This may seems weird but that's because you read numbers from right to left.
98			return (\hexdec($hex[$realByteNth]) << 4) + \hexdec($hex[$realByteNth + 1]);
99			// _Notice that if the number is from right to left, your data is still from left to right_
100			}
101
102			throw new \InvalidArgumentException(
103			\sprintf('The frame must be an int or string, %s given.', gettype($frame))
104			);
105			}
106
107			public static function partOfByte(int $byte, int $part) : int
108			{
109			if ($byte < 0 \|\| $byte > 255) {
110			throw new \InvalidArgumentException(sprintf('%s is not a byte', $byte));
111			}
112
113			if ($part === 1) {
114			return ($byte & 240) >> 4;
115			}
116
117			if ($part === 2) {
118			return $byte & 15;
119			}
120
121			throw new \InvalidArgumentException(sprintf('A byte have only 2 parts. %s asked.', $part));
122			}
123
124			/**
125			* Because strings are the best way to store many bytes in PHP it can
126			* be useful to make the conversion between hex (which are strings)
127			* array to string.
128			*
129			* @param array $hexArray
130			* @return string
131			*/
132			public static function hexArrayToString(...$hexArray) : string
133			{
134			if (\is_array($hexArray[0])) {
135			$hexArray = $hexArray[0];
136			}
137
138			$res = '';
139			foreach ($hexArray as $hexNum) {
140			$res .= \chr(\hexdec($hexNum));
141			}
142
143			return $res;
144			}
145
146			/**
147			* @param string\|int $frame
148			* @param int $from Byte where to start (should be inferior to $to).
149			* @param int $to Byte where to stop (considering it starts at 0). The `to` value include the target
150			* byte.
151			* @param bool $force8bytes By default PHP have a wrong behavior with 8 bytes variables. If you have 8 bytes
152			* the returned int will be negative (because unsigned integers does not exists in PHP)
153			* @return int
154			*/
155			public static function bytesFromTo($frame, int $from, int $to, bool $force8bytes = false) : int
156			{
157			// No more than 64b (which return negative number when the first bit is specified)
158			if (($to - $from) > 7 && (!$force8bytes && ($to - $from) !== 8)) {
159			if ($force8bytes) {
160			throw new \InvalidArgumentException(sprintf('Not more than 8 bytes (64bit) is supported by this method and you asked for %s bytes.', $to - $from));
161			}
162			throw new \InvalidArgumentException('PHP limitation: getting more than 7 bytes will return a negative number because unsigned int does not exist.');
163			}
164
165			if (\is_string($frame)) {
166			if ((BitManipulation::frameSize($frame) - 1) < $to) {
167			throw new NotLongEnoughException('The frame is not long enough.');
168			}
169
170			$subStringLength = $to - $from + 1;
171			// Getting responsible bytes
172			$subString = \substr($frame, $from, $subStringLength);
173			$res = 0;
174
175			// for each byte, getting ord
176			for($i = 0; $i < $subStringLength; $i++) {
177			$res <<= 8;
178			$res += \ord($subString[$i]);
179			}
180
181			return $res;
182			}
183
184			if (!\is_int($frame)) {
185			throw new \InvalidArgumentException(
186			\sprintf('A frame can only be a string or int. %s given', gettype($frame))
187			);
188			}
189
190			if ($frame < 0) {
191			throw new \InvalidArgumentException('The frame cannot be a negative number');
192			}
193
194			$res = 0;
195			for ($i = $from; $i <= $to; $i++) {
196			$res <<= 8;
197			$res += BitManipulation::nthByte($frame, $i);
198			}
199
200			return $res;
201			}
202
203			/**
204			* Proxy to the substr to be sure to be use the right method (mb_substr)
205			*
206			* @param string $frame
207			* @param int $from
208			* @param int $to
209			* @return string
210			*/
211			public static function bytesFromToString(string $frame, int $from, int $to, int $mode = BitManipulation::MODE_FROM_TO) : string
212			{
213			if ($mode === BitManipulation::MODE_FROM_TO) {
214			return \mb_substr($frame, $from, $to - $from + 1, '8bit');
215			}
216
217			return \mb_substr($frame, $from, $to, '8bit');
218			}
219
220			/**
221			* Take a frame represented by a decimal int to transform it in a string.
222			* Notice that any int is a frame and cannot be more than 8 bytes
223			*
224			* @param int $frame
225			* @param int\|null $size In bytes. This value should always be precise. Be careful if you don't !
226			* @return string
227			*/
228			public static function intToBinaryString(int $frame, int $size = null) : string
229			{
230			$format = 'J*';
231
232			if ($size !== null) {
233			switch (true) {
234			case $size <= 2:
235			$format = 'n*';
236			break;
237			case $size <= 4:
238			$format = 'N*';
239			break;
240			case $size > 4:
241			$format = 'J*';
242			break;
243			}
244			}
245
246			$res = pack($format, $frame);
247
248			if ($size === null) {
249			$res = ltrim($res, "\0");
250			}
251
252			return $res;
253			}
254
255			/**
256			* Take an string frame and transform it to a decimal frame (inside an int).
257			*
258			* @param string $frame
259			* @return int
260			*/
261			public static function binaryToInt(string $frame) : int
262			{
263			$len = BitManipulation::frameSize($frame);
264
265			if ($len > 8) {
266			throw new \InvalidArgumentException(
267			\sprintf('The string %s cannot be converted to int because an int cannot be more than 8 bytes (64b).', $frame)
268			);
269			}
270
271			switch(true) {
272			case $len <= 2:
273			$format = 'n';
274			break;
275			case $len <= 4:
276			$format = 'N';
277			break;
278			case $len > 4:
279			$format = 'J';
280			break;
281			}
282
283			return unpack($format, $frame)[1];
			0 ignored issues – show Bug introduced 2017-07-27 21:40 UTC by Report Bug Copy Issue Report The variable `$format` does not seem to be defined for all execution paths leading up to this point. If you define a variable conditionally, it can happen that it is not defined for all execution paths. Let’s take a look at an example: function myFunction($a) { switch ($a) { case 'foo': $x = 1; break; case 'bar': $x = 2; break; } // $x is potentially undefined here. echo $x; } In the above example, the variable `$x` is defined if you pass “foo” or “bar” as argument for `$a`. However, since the `switch` statement has no default case statement, if you pass any other value, the variable `$x` would be undefined. Available Fixes Check for existence of the variable explicitly: function myFunction($a) { switch ($a) { case 'foo': $x = 1; break; case 'bar': $x = 2; break; } if (isset($x)) { // Make sure it's always set. echo $x; } } Define a default value for the variable: function myFunction($a) { $x = ''; // Set a default which gets overridden for certain paths. switch ($a) { case 'foo': $x = 1; break; case 'bar': $x = 2; break; } echo $x; } Add a value for the missing path: function myFunction($a) { switch ($a) { case 'foo': $x = 1; break; case 'bar': $x = 2; break; // We add support for the missing case. default: $x = ''; break; } echo $x; } Loading history...
284			}
285
286			/**
287			* Method that return frame as hex (more readable).
288			* Helpful for debug !
289			*
290			* @param string $frame
291			* @return string
292			*/
293			public static function binaryToHex(string $frame) : string
294			{
295			return unpack('H*', $frame)[1];
296			}
297
298			/**
299			* Haters gonna hate. `strlen` cannot be trusted because of an option of mbstring extension, more info:
300			* http://php.net/manual/fr/mbstring.overload.php
301			* http://php.net/manual/fr/function.mb-strlen.php#77040
302			*
303			* @param string $frame
304			* @return int
305			*/
306			public static function frameSize(string $frame) : int
307			{
308			if (\extension_loaded('mbstring')) {
309			return \mb_strlen($frame, '8bit');
310			}
311
312			return \strlen($frame);
313			}
314			}
315

Nekland / Woketo

Pull Request — master (#118)

BitManipulation::intToBinaryString() B

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