main.js ➔ unpackFrom - Code Metrics - Inspection of "UTF-8" - rochars/byte-data - Measure and Improve Code Quality continuously with Scrutinizer

Passed

Push — master ( 365af9...d62841 )

by Rafael S.

created 2018-07-15 05:35 UTC

main.js ➔ unpackFrom A

↳ Parent: main.js

Complexity

Conditions	3
Paths	4

Size

Total Lines	11
Code Lines	8

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	3
eloc	8
nc	4
dl	0
loc	11
rs	10
c	0
b	0
f	0
nop	3

/*
 * Copyright (c) 2017-2018 Rafael da Silva Rocha.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

/**
 * @fileoverview The byte-data API.
 * @see https://github.com/rochars/byte-data
 */

/** @module byteData */

import endianness from './lib/endianness.js';
import {reader_, setUp_, writeBytes_} from './lib/packer.js';
import {validateNotUndefined} from './lib/validation.js';

/**
 * Read a string of UTF-8 characters from a byte buffer.
 * @see https://encoding.spec.whatwg.org/#the-encoding
 * @see https://stackoverflow.com/a/34926911
 * @param {!Uint8Array|!Array<!number>} buffer A byte buffer.
 * @param {number=} index The index to read.
 * @param {?number=} len The number of bytes to read.
 * @return {string}
 * @throws {Error} If read a value that is not UTF-8.
 */
export function unpackString(buffer, index=0, len=null) {
  len = len !== null ? index + len : buffer.length;
  /** @type {string} */
  let str = "";
  while(index < len) {
    /** @type {number} */
    let charCode = buffer[index++];
    if (charCode >> 7 == 0) {

      str += String.fromCharCode(charCode);
    } else {
      /** @type {number} */
      let count = 0;
      if (charCode >> 5 == 0x06) {
        count = 1;
      } else if (charCode >> 4 == 0x0e) {
        count = 2;
      } else if (charCode >> 3 == 0x1e) {
        count = 3;
      }
      charCode = charCode & (1 << (8 - count - 1)) - 1;
      for (let i = 0; i < count; i++) {
        charCode = (charCode << 6) | (buffer[index++] & 0x3f);
      }
      if (charCode <= 0xffff) {
        str += String.fromCharCode(charCode);
      } else {
        charCode -= 0x10000;
        str += String.fromCharCode(
          ((charCode >> 10) & 0x3ff) + 0xd800,
          (charCode & 0x3ff) + 0xdc00);
      }
    }
  }
  return str;
}

/**
 * Write a string of UTF-8 characters as a byte buffer.
 * @see https://encoding.spec.whatwg.org/#utf-8-encoder
 * @param {string} str The string to pack.
 * @return {!Array<number>} The next index to write on the buffer.
 * @throws {Error} If a character in the string is not UTF-8.
 */
export function packString(str) {
  /** @type {!Array<!number>} */
  let bytes = [];
  for (let i = 0; i < str.length; i++) {
    /** @type {number} */
    let codePoint = str.codePointAt(i);
    if (codePoint < 128) {
      bytes.push(codePoint);
    } else {
      /** @type {number} */
      let count = 0;
      /** @type {number} */
      let offset = 0;
      if (codePoint <= 0x07FF) {
        count = 1;
        offset = 0xC0;
      } else if(codePoint <= 0xFFFF) {
        count = 2;
        offset = 0xE0;
      } else if(codePoint <= 0x10FFFF) {
        count = 3;
        offset = 0xF0;
        i++;

      }
      bytes.push((codePoint >> (6 * count)) + offset);
      while (count > 0) {
        bytes.push(0x80 | (codePoint >> (6 * (count - 1)) & 0x3F));
        count--;
      }
    }
  }
  return bytes;
}

/**
 * Write a string of UTF-8 characters to a byte buffer.
 * @param {string} str The string to pack.
 * @param {!Uint8Array|!Array<number>} buffer The output buffer.
 * @param {number=} index The index to write in the buffer.
 * @return {number} The next index to write in the buffer.
 * @throws {Error} If a character in the string is not valid ASCII.
 */
export function packStringTo(str, buffer, index=0) {
  /** @type {!Array<!number>} */
  let bytes = packString(str);
  for (let i = 0; i < bytes.length; i++) {
    buffer[index++] = bytes[i];
  }
  return index;
}

// Numbers
/**
 * Pack a number as a byte buffer.
 * @param {number} value The number.
 * @param {!Object} theType The type definition.
 * @return {!Array<number>} The packed value.
 * @throws {Error} If the type definition is not valid.
 * @throws {Error} If the value is not valid.
 */
export function pack(value, theType) {
  /** @type {!Array<!number>} */
  let output = [];
  packTo(value, theType, output);
  return output;
}

/**
 * Pack an array of numbers as a byte buffer.
 * @param {!Array<number>|!TypedArray} values The values.
 * @param {!Object} theType The type definition.
 * @return {!Array<number>} The packed values.
 * @throws {Error} If the type definition is not valid.
 * @throws {Error} If any of the values are not valid.
 */
export function packArray(values, theType) {
  /** @type {!Array<!number>} */
  let output = [];
  packArrayTo(values, theType, output);
  return output;
}

/**
 * Pack a number to a byte buffer.
 * @param {number} value The value.
 * @param {!Object} theType The type definition.
 * @param {!Uint8Array|!Array<number>} buffer The output buffer.
 * @param {number=} index The index to write.
 * @return {number} The next index to write.
 * @throws {Error} If the type definition is not valid.
 * @throws {Error} If the value is not valid.
 */
export function packTo(value, theType, buffer, index=0) {
  setUp_(theType);
  return writeBytes_(value,
    theType,
    buffer,
    index,
    index + theType.offset,
    validateNotUndefined,
    theType.be);
}

/**
 * Pack a array of numbers to a byte buffer.
 * @param {!Array<number>|!TypedArray} values The value.
 * @param {!Object} theType The type definition.
 * @param {!Uint8Array|!Array<number>} buffer The output buffer.
 * @param {number=} index The buffer index to write.
 * @return {number} The next index to write.
 * @throws {Error} If the type definition is not valid.
 * @throws {Error} If the value is not valid.
 */
export function packArrayTo(values, theType, buffer, index=0) {
  setUp_(theType);
  for (let i=0; i < values.length; i++) {
    index = writeBytes_(
      values[i],
      theType,
      buffer,
      index,
      index + theType.offset,
      validateNotUndefined,
      theType.be);
  }
  return index;
}

/**
 * Unpack a number from a byte buffer.
 * @param {!Uint8Array|!Array<!number>} buffer The byte buffer.
 * @param {!Object} theType The type definition.
 * @param {number=} index The buffer index to read.
 * @return {number}
 * @throws {Error} If the type definition is not valid
 */
export function unpack(buffer, theType, index=0) {
  setUp_(theType);
  if (theType.be) {
    endianness(buffer, theType.offset, index, index + theType.offset);
  }
  /** @type {number} */
  let value = reader_(buffer, index);
  if (theType.be) {
    endianness(buffer, theType.offset, index, index + theType.offset);
  }
  return value;
}

/**
 * Unpack an array of numbers from a byte buffer.
 * @param {!Uint8Array|!Array<!number>} buffer The byte buffer.
 * @param {!Object} theType The type definition.
 * @param {number=} index The start index. Assumes 0.
 * @param {?number=} end The end index. Assumes the buffer length.
 * @return {!Array<number>}
 * @throws {Error} If the type definition is not valid
 */
export function unpackArray(buffer, theType, index=0, end=buffer.length) {
  /** @type {!Array<!number>} */
  let output = [];
  unpackArrayTo(buffer, theType, output, index, end);
  return output;
}

/**
 * Unpack a array of numbers to a typed array.
 * @param {!Uint8Array|!Array<!number>} buffer The byte buffer.
 * @param {!Object} theType The type definition.
 * @param {!TypedArray|!Array<!number>} output The output array.
 * @param {number=} index The start index. Assumes 0.
 * @param {?number=} end The end index. Assumes the buffer length.
 * @throws {Error} If the type definition is not valid
 */
export function unpackArrayTo(buffer, theType, output, index=0, end=buffer.length) {
  setUp_(theType);
  while ((end - index) % theType.offset) {
    end--;
  }
  if (theType.be) {
    endianness(buffer, theType.offset);
  }
  for (let i = 0; index < end; index += theType.offset, i++) {

    output[i] = reader_(buffer, index);
  }
  if (theType.be) {
    endianness(buffer, theType.offset);
  }
}


1			/*
2			* Copyright (c) 2017-2018 Rafael da Silva Rocha.
3			*
4			* Permission is hereby granted, free of charge, to any person obtaining
5			* a copy of this software and associated documentation files (the
6			* "Software"), to deal in the Software without restriction, including
7			* without limitation the rights to use, copy, modify, merge, publish,
8			* distribute, sublicense, and/or sell copies of the Software, and to
9			* permit persons to whom the Software is furnished to do so, subject to
10			* the following conditions:
11			*
12			* The above copyright notice and this permission notice shall be
13			* included in all copies or substantial portions of the Software.
14			*
15			* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16			* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17			* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18			* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
19			* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
20			* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
21			* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22			*
23			*/
24
25			/**
26			* @fileoverview The byte-data API.
27			* @see https://github.com/rochars/byte-data
28			*/
29
30			/** @module byteData */
31
32			import endianness from './lib/endianness.js';
33			import {reader_, setUp_, writeBytes_} from './lib/packer.js';
34			import {validateNotUndefined} from './lib/validation.js';
35
36			/**
37			* Read a string of UTF-8 characters from a byte buffer.
38			* @see https://encoding.spec.whatwg.org/#the-encoding
39			* @see https://stackoverflow.com/a/34926911
40			* @param {!Uint8Array\|!Array<!number>} buffer A byte buffer.
41			* @param {number=} index The index to read.
42			* @param {?number=} len The number of bytes to read.
43			* @return {string}
44			* @throws {Error} If read a value that is not UTF-8.
45			*/
46			export function unpackString(buffer, index=0, len=null) {
47			len = len !== null ? index + len : buffer.length;
48			/** @type {string} */
49			let str = "";
50			while(index < len) {
51			/** @type {number} */
52			let charCode = buffer[index++];
53			if (charCode >> 7 == 0) {
			0 ignored issues – show Best Practice introduced 2018-07-15 05:37 UTC by Report Bug Copy Issue Report Comparing `charCode >> 7` to `0` using the `==` operator is not safe. Consider using `===` instead. Loading history...
54			str += String.fromCharCode(charCode);
55			} else {
56			/** @type {number} */
57			let count = 0;
58			if (charCode >> 5 == 0x06) {
59			count = 1;
60			} else if (charCode >> 4 == 0x0e) {
61			count = 2;
62			} else if (charCode >> 3 == 0x1e) {
63			count = 3;
64			}
65			charCode = charCode & (1 << (8 - count - 1)) - 1;
66			for (let i = 0; i < count; i++) {
67			charCode = (charCode << 6) \| (buffer[index++] & 0x3f);
68			}
69			if (charCode <= 0xffff) {
70			str += String.fromCharCode(charCode);
71			} else {
72			charCode -= 0x10000;
73			str += String.fromCharCode(
74			((charCode >> 10) & 0x3ff) + 0xd800,
75			(charCode & 0x3ff) + 0xdc00);
76			}
77			}
78			}
79			return str;
80			}
81
82			/**
83			* Write a string of UTF-8 characters as a byte buffer.
84			* @see https://encoding.spec.whatwg.org/#utf-8-encoder
85			* @param {string} str The string to pack.
86			* @return {!Array<number>} The next index to write on the buffer.
87			* @throws {Error} If a character in the string is not UTF-8.
88			*/
89			export function packString(str) {
90			/** @type {!Array<!number>} */
91			let bytes = [];
92			for (let i = 0; i < str.length; i++) {
93			/** @type {number} */
94			let codePoint = str.codePointAt(i);
95			if (codePoint < 128) {
96			bytes.push(codePoint);
97			} else {
98			/** @type {number} */
99			let count = 0;
100			/** @type {number} */
101			let offset = 0;
102			if (codePoint <= 0x07FF) {
103			count = 1;
104			offset = 0xC0;
105			} else if(codePoint <= 0xFFFF) {
106			count = 2;
107			offset = 0xE0;
108			} else if(codePoint <= 0x10FFFF) {
109			count = 3;
110			offset = 0xF0;
111			i++;
			0 ignored issues – show Complexity Coding Style introduced 2018-07-15 05:37 UTC by Report Bug Copy Issue Report You seem to be assigning a new value to the loop variable `i` here. Please check if this was indeed your intention. Even if it was, consider using another kind of loop instead. Loading history...
112			}
113			bytes.push((codePoint >> (6 * count)) + offset);
114			while (count > 0) {
115			bytes.push(0x80 \| (codePoint >> (6 * (count - 1)) & 0x3F));
116			count--;
117			}
118			}
119			}
120			return bytes;
121			}
122
123			/**
124			* Write a string of UTF-8 characters to a byte buffer.
125			* @param {string} str The string to pack.
126			* @param {!Uint8Array\|!Array<number>} buffer The output buffer.
127			* @param {number=} index The index to write in the buffer.
128			* @return {number} The next index to write in the buffer.
129			* @throws {Error} If a character in the string is not valid ASCII.
130			*/
131			export function packStringTo(str, buffer, index=0) {
132			/** @type {!Array<!number>} */
133			let bytes = packString(str);
134			for (let i = 0; i < bytes.length; i++) {
135			buffer[index++] = bytes[i];
136			}
137			return index;
138			}
139
140			// Numbers
141			/**
142			* Pack a number as a byte buffer.
143			* @param {number} value The number.
144			* @param {!Object} theType The type definition.
145			* @return {!Array<number>} The packed value.
146			* @throws {Error} If the type definition is not valid.
147			* @throws {Error} If the value is not valid.
148			*/
149			export function pack(value, theType) {
150			/** @type {!Array<!number>} */
151			let output = [];
152			packTo(value, theType, output);
153			return output;
154			}
155
156			/**
157			* Pack an array of numbers as a byte buffer.
158			* @param {!Array<number>\|!TypedArray} values The values.
159			* @param {!Object} theType The type definition.
160			* @return {!Array<number>} The packed values.
161			* @throws {Error} If the type definition is not valid.
162			* @throws {Error} If any of the values are not valid.
163			*/
164			export function packArray(values, theType) {
165			/** @type {!Array<!number>} */
166			let output = [];
167			packArrayTo(values, theType, output);
168			return output;
169			}
170
171			/**
172			* Pack a number to a byte buffer.
173			* @param {number} value The value.
174			* @param {!Object} theType The type definition.
175			* @param {!Uint8Array\|!Array<number>} buffer The output buffer.
176			* @param {number=} index The index to write.
177			* @return {number} The next index to write.
178			* @throws {Error} If the type definition is not valid.
179			* @throws {Error} If the value is not valid.
180			*/
181			export function packTo(value, theType, buffer, index=0) {
182			setUp_(theType);
183			return writeBytes_(value,
184			theType,
185			buffer,
186			index,
187			index + theType.offset,
188			validateNotUndefined,
189			theType.be);
190			}
191
192			/**
193			* Pack a array of numbers to a byte buffer.
194			* @param {!Array<number>\|!TypedArray} values The value.
195			* @param {!Object} theType The type definition.
196			* @param {!Uint8Array\|!Array<number>} buffer The output buffer.
197			* @param {number=} index The buffer index to write.
198			* @return {number} The next index to write.
199			* @throws {Error} If the type definition is not valid.
200			* @throws {Error} If the value is not valid.
201			*/
202			export function packArrayTo(values, theType, buffer, index=0) {
203			setUp_(theType);
204			for (let i=0; i < values.length; i++) {
205			index = writeBytes_(
206			values[i],
207			theType,
208			buffer,
209			index,
210			index + theType.offset,
211			validateNotUndefined,
212			theType.be);
213			}
214			return index;
215			}
216
217			/**
218			* Unpack a number from a byte buffer.
219			* @param {!Uint8Array\|!Array<!number>} buffer The byte buffer.
220			* @param {!Object} theType The type definition.
221			* @param {number=} index The buffer index to read.
222			* @return {number}
223			* @throws {Error} If the type definition is not valid
224			*/
225			export function unpack(buffer, theType, index=0) {
226			setUp_(theType);
227			if (theType.be) {
228			endianness(buffer, theType.offset, index, index + theType.offset);
229			}
230			/** @type {number} */
231			let value = reader_(buffer, index);
232			if (theType.be) {
233			endianness(buffer, theType.offset, index, index + theType.offset);
234			}
235			return value;
236			}
237
238			/**
239			* Unpack an array of numbers from a byte buffer.
240			* @param {!Uint8Array\|!Array<!number>} buffer The byte buffer.
241			* @param {!Object} theType The type definition.
242			* @param {number=} index The start index. Assumes 0.
243			* @param {?number=} end The end index. Assumes the buffer length.
244			* @return {!Array<number>}
245			* @throws {Error} If the type definition is not valid
246			*/
247			export function unpackArray(buffer, theType, index=0, end=buffer.length) {
248			/** @type {!Array<!number>} */
249			let output = [];
250			unpackArrayTo(buffer, theType, output, index, end);
251			return output;
252			}
253
254			/**
255			* Unpack a array of numbers to a typed array.
256			* @param {!Uint8Array\|!Array<!number>} buffer The byte buffer.
257			* @param {!Object} theType The type definition.
258			* @param {!TypedArray\|!Array<!number>} output The output array.
259			* @param {number=} index The start index. Assumes 0.
260			* @param {?number=} end The end index. Assumes the buffer length.
261			* @throws {Error} If the type definition is not valid
262			*/
263			export function unpackArrayTo(buffer, theType, output, index=0, end=buffer.length) {
264			setUp_(theType);
265			while ((end - index) % theType.offset) {
266			end--;
267			}
268			if (theType.be) {
269			endianness(buffer, theType.offset);
270			}
271			for (let i = 0; index < end; index += theType.offset, i++) {
			0 ignored issues – show Unused Code introduced 2018-07-15 05:37 UTC by Report Bug Copy Issue Report The loop variable `i` is initialized by the loop but not used in the test. Consider using another type of loop if this is the intended behavior. Loading history...
272			output[i] = reader_(buffer, index);
273			}
274			if (theType.be) {
275			endianness(buffer, theType.offset);
276			}
277			}
278

rochars / byte-data

Push — master ( 365af9...d62841 )

main.js ➔ unpackFrom A

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