1 | /* |
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2 | * Copyright (c) 2017-2018 Rafael da Silva Rocha. |
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3 | * |
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4 | * Permission is hereby granted, free of charge, to any person obtaining |
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5 | * a copy of this software and associated documentation files (the |
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6 | * "Software"), to deal in the Software without restriction, including |
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7 | * without limitation the rights to use, copy, modify, merge, publish, |
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8 | * distribute, sublicense, and/or sell copies of the Software, and to |
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9 | * permit persons to whom the Software is furnished to do so, subject to |
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10 | * the following conditions: |
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11 | * |
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12 | * The above copyright notice and this permission notice shall be |
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13 | * included in all copies or substantial portions of the Software. |
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14 | * |
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15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
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16 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
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17 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
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18 | * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
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19 | * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
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20 | * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
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21 | * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
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22 | * |
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23 | */ |
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24 | |||
25 | /** |
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26 | * @fileoverview The byte-data API. |
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27 | * @see https://github.com/rochars/byte-data |
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28 | */ |
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29 | |||
30 | /** @module byteData */ |
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31 | |||
32 | import endianness from './lib/endianness.js'; |
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33 | import utf8BufferSize from './lib/utf8-buffer-size.js'; |
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34 | import {reader_, setUp_, writer_} from './lib/packer.js'; |
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35 | import {validateNotUndefined, validateValueType} from './lib/validation.js'; |
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36 | |||
37 | /** |
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38 | * Read a string of UTF-8 characters from a byte buffer. |
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39 | * @see https://encoding.spec.whatwg.org/#the-encoding |
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40 | * @see https://stackoverflow.com/a/34926911 |
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41 | * @param {!Uint8Array|!Array<!number>} buffer A byte buffer. |
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42 | * @param {number=} index The index to read. |
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43 | * @param {?number=} len The number of bytes to read. |
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44 | * If len is undefined will read until the end of the buffer. |
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45 | * @return {string} |
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46 | */ |
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47 | export function unpackString(buffer, index=0, len=undefined) { |
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48 | len = len !== undefined ? index + len : buffer.length; |
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49 | /** @type {string} */ |
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50 | let str = ""; |
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51 | while(index < len) { |
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52 | /** @type {number} */ |
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53 | let lowerBoundary = 0x80; |
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54 | /** @type {number} */ |
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55 | let upperBoundary = 0xBF; |
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56 | /** @type {boolean} */ |
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57 | let replace = false; |
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58 | /** @type {number} */ |
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59 | let charCode = buffer[index++]; |
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60 | if (charCode >= 0x00 && charCode <= 0x7F) { |
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61 | str += String.fromCharCode(charCode); |
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62 | } else { |
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63 | /** @type {number} */ |
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64 | let count = 0; |
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65 | if (charCode >= 0xC2 && charCode <= 0xDF) { |
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66 | count = 1; |
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67 | } else if (charCode >= 0xE0 && charCode <= 0xEF ) { |
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68 | count = 2; |
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69 | if (buffer[index] === 0xE0) { |
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70 | lowerBoundary = 0xA0; |
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71 | } |
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72 | if (buffer[index] === 0xED) { |
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73 | upperBoundary = 0x9F; |
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74 | } |
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75 | } else if (charCode >= 0xF0 && charCode <= 0xF4 ) { |
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76 | count = 3; |
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77 | if (buffer[index] === 0xF0) { |
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78 | lowerBoundary = 0x90; |
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79 | } |
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80 | if (buffer[index] === 0xF4) { |
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81 | upperBoundary = 0x8F; |
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82 | } |
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83 | } else { |
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84 | replace = true; |
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85 | } |
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86 | charCode = charCode & (1 << (8 - count - 1)) - 1; |
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87 | for (let i = 0; i < count; i++) { |
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88 | if (buffer[index] < lowerBoundary || buffer[index] > upperBoundary) { |
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89 | replace = true; |
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90 | } |
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91 | charCode = (charCode << 6) | (buffer[index] & 0x3f); |
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92 | index++; |
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93 | } |
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94 | if (replace) { |
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95 | str += String.fromCharCode(0xFFFD); |
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96 | } |
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97 | else if (charCode <= 0xffff) { |
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98 | str += String.fromCharCode(charCode); |
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99 | } else { |
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100 | charCode -= 0x10000; |
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101 | str += String.fromCharCode( |
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102 | ((charCode >> 10) & 0x3ff) + 0xd800, |
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103 | (charCode & 0x3ff) + 0xdc00); |
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104 | } |
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105 | } |
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106 | } |
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107 | return str; |
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108 | } |
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109 | |||
110 | /** |
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111 | * Write a string of UTF-8 characters as a byte buffer. |
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112 | * @see https://encoding.spec.whatwg.org/#utf-8-encoder |
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113 | * @param {string} str The string to pack. |
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114 | * @return {!Uint8Array} The packed string. |
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115 | */ |
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116 | export function packString(str) { |
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117 | /** @type {!Uint8Array} */ |
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118 | let bytes = new Uint8Array(utf8BufferSize(str)); |
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119 | let bufferIndex = 0; |
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120 | for (let i = 0, len = str.length; i < len; i++) { |
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121 | /** @type {number} */ |
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122 | let codePoint = str.codePointAt(i); |
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123 | if (codePoint < 128) { |
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124 | bytes[bufferIndex] = codePoint; |
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125 | bufferIndex++; |
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126 | } else { |
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127 | /** @type {number} */ |
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128 | let count = 0; |
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129 | /** @type {number} */ |
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130 | let offset = 0; |
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131 | if (codePoint <= 0x07FF) { |
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132 | count = 1; |
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133 | offset = 0xC0; |
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134 | } else if(codePoint <= 0xFFFF) { |
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135 | count = 2; |
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136 | offset = 0xE0; |
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137 | } else if(codePoint <= 0x10FFFF) { |
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138 | count = 3; |
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139 | offset = 0xF0; |
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140 | i++; |
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141 | } |
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142 | bytes[bufferIndex] = (codePoint >> (6 * count)) + offset; |
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143 | bufferIndex++; |
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144 | while (count > 0) { |
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145 | bytes[bufferIndex] = 0x80 | (codePoint >> (6 * (count - 1)) & 0x3F); |
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146 | bufferIndex++; |
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147 | count--; |
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148 | } |
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149 | } |
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150 | } |
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151 | return bytes; |
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152 | } |
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153 | |||
154 | /** |
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155 | * Write a string of UTF-8 characters to a byte buffer. |
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156 | * @param {string} str The string to pack. |
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157 | * @param {!Uint8Array|!Array<number>} buffer The output buffer. |
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158 | * @param {number=} index The buffer index to start writing. |
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159 | * Assumes zero if undefined. |
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160 | * @return {number} The next index to write in the buffer. |
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161 | */ |
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162 | export function packStringTo(str, buffer, index=0) { |
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163 | /** @type {!Uint8Array} */ |
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164 | let bytes = packString(str); |
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165 | for (let i = 0, len = bytes.length; i < len; i++) { |
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166 | buffer[index++] = bytes[i]; |
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167 | } |
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168 | return index; |
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169 | } |
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170 | |||
171 | // Numbers |
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172 | /** |
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173 | * Pack a number as a byte buffer. |
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174 | * @param {number} value The number. |
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175 | * @param {!Object} theType The type definition. |
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176 | * @return {!Array<number>} The packed value. |
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177 | * @throws {Error} If the type definition is not valid. |
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178 | * @throws {Error} If the value is not valid. |
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179 | */ |
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180 | export function pack(value, theType) { |
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181 | /** @type {!Array<!number>} */ |
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182 | let output = []; |
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183 | packTo(value, theType, output); |
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184 | return output; |
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185 | } |
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186 | |||
187 | /** |
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188 | * Pack a number to a byte buffer. |
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189 | * @param {number} value The value. |
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190 | * @param {!Object} theType The type definition. |
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191 | * @param {!Uint8Array|!Array<number>} buffer The output buffer. |
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192 | * @param {number=} index The buffer index to write. Assumes 0 if undefined. |
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193 | * @return {number} The next index to write. |
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194 | * @throws {Error} If the type definition is not valid. |
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195 | * @throws {Error} If the value is not valid. |
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196 | */ |
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197 | export function packTo(value, theType, buffer, index=0) { |
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198 | return packArrayTo([value], theType, buffer, index); |
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199 | } |
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200 | |||
201 | /** |
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202 | * Pack an array of numbers as a byte buffer. |
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203 | * @param {!Array<number>|!TypedArray} values The values. |
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204 | * @param {!Object} theType The type definition. |
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205 | * @return {!Array<number>} The packed values. |
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206 | * @throws {Error} If the type definition is not valid. |
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207 | * @throws {Error} If any of the values are not valid. |
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208 | */ |
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209 | export function packArray(values, theType) { |
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210 | /** @type {!Array<!number>} */ |
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211 | let output = []; |
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212 | packArrayTo(values, theType, output); |
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213 | return output; |
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214 | } |
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215 | |||
216 | /** |
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217 | * Pack a array of numbers to a byte buffer. |
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218 | * @param {!Array<number>|!TypedArray} values The value. |
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219 | * @param {!Object} theType The type definition. |
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220 | * @param {!Uint8Array|!Array<number>} buffer The output buffer. |
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221 | * @param {number=} index The buffer index to start writing. |
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222 | * Assumes zero if undefined. |
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223 | * @return {number} The next index to write. |
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224 | * @throws {Error} If the type definition is not valid. |
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225 | * @throws {Error} If the value is not valid. |
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226 | */ |
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227 | export function packArrayTo(values, theType, buffer, index=0) { |
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228 | setUp_(theType); |
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229 | for (let i = 0, valuesLen = values.length; i < valuesLen; i++) { |
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230 | validateNotUndefined(values[i]); |
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231 | validateValueType(values[i]); |
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232 | /** @type {number} */ |
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233 | let len = index + theType.offset; |
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234 | while (index < len) { |
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235 | index = writer_(buffer, values[i], index); |
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236 | } |
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237 | if (theType.be) { |
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238 | endianness( |
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239 | buffer, theType.offset, index - theType.offset, index); |
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240 | } |
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241 | } |
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242 | return index; |
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243 | } |
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244 | |||
245 | /** |
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246 | * Unpack a number from a byte buffer. |
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247 | * @param {!Uint8Array|!Array<!number>} buffer The byte buffer. |
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248 | * @param {!Object} theType The type definition. |
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249 | * @param {number=} index The buffer index to read. Assumes zero if undefined. |
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250 | * @return {number} |
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251 | * @throws {Error} If the type definition is not valid |
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252 | * @throws {Error} On bad buffer length. |
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253 | */ |
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254 | export function unpack(buffer, theType, index=0) { |
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255 | setUp_(theType); |
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256 | if ((theType.offset + index) > buffer.length) { |
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257 | throw Error('Bad buffer length.'); |
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258 | } |
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259 | if (theType.be) { |
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260 | endianness(buffer, theType.offset, index, index + theType.offset); |
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261 | } |
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262 | /** @type {number} */ |
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263 | let value = reader_(buffer, index); |
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264 | if (theType.be) { |
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265 | endianness(buffer, theType.offset, index, index + theType.offset); |
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266 | } |
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267 | return value; |
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268 | } |
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269 | |||
270 | /** |
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271 | * Unpack an array of numbers from a byte buffer. |
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272 | * @param {!Uint8Array|!Array<!number>} buffer The byte buffer. |
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273 | * @param {!Object} theType The type definition. |
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274 | * @param {number=} index The buffer index to start reading. |
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275 | * Assumes zero if undefined. |
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276 | * @param {number=} end The buffer index to stop reading. |
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277 | * Assumes the buffer length if undefined. |
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278 | * @return {!Array<number>} |
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279 | * @throws {Error} If the type definition is not valid |
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280 | */ |
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281 | export function unpackArray(buffer, theType, index=0, end=buffer.length) { |
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282 | /** @type {!Array<!number>} */ |
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283 | let output = []; |
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284 | unpackArrayTo(buffer, theType, output, index, end); |
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285 | return output; |
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286 | } |
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287 | |||
288 | /** |
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289 | * Unpack a array of numbers to a typed array. |
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290 | * @param {!Uint8Array|!Array<!number>} buffer The byte buffer. |
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291 | * @param {!Object} theType The type definition. |
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292 | * @param {!TypedArray|!Array<!number>} output The output array. |
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293 | * @param {number=} index The buffer index to start reading. |
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294 | * Assumes zero if undefined. |
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295 | * @param {number=} end The buffer index to stop reading. |
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296 | * Assumes the buffer length if undefined. |
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297 | * @throws {Error} If the type definition is not valid |
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298 | */ |
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299 | export function unpackArrayTo( |
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300 | buffer, theType, output, index=0, end=buffer.length) { |
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301 | setUp_(theType); |
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302 | while ((end - index) % theType.offset) { |
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303 | end--; |
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304 | } |
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305 | for (let i = 0; index < end; index += theType.offset, i++) { |
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306 | output[i] = unpack(buffer, theType, index); |
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307 | } |
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308 | } |
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309 |