Kaido Kert | f585e26 | 2020-06-08 11:42:28 -0700 | [diff] [blame] | 1 | "use strict"; |
| 2 | var Buffer = require("buffer").Buffer; |
| 3 | // Note: not polyfilled with safer-buffer on a purpose, as overrides Buffer |
| 4 | |
| 5 | // == Extend Node primitives to use iconv-lite ================================= |
| 6 | |
| 7 | module.exports = function (iconv) { |
| 8 | var original = undefined; // Place to keep original methods. |
| 9 | |
| 10 | // Node authors rewrote Buffer internals to make it compatible with |
| 11 | // Uint8Array and we cannot patch key functions since then. |
| 12 | // Note: this does use older Buffer API on a purpose |
| 13 | iconv.supportsNodeEncodingsExtension = !(Buffer.from || new Buffer(0) instanceof Uint8Array); |
| 14 | |
| 15 | iconv.extendNodeEncodings = function extendNodeEncodings() { |
| 16 | if (original) return; |
| 17 | original = {}; |
| 18 | |
| 19 | if (!iconv.supportsNodeEncodingsExtension) { |
| 20 | console.error("ACTION NEEDED: require('iconv-lite').extendNodeEncodings() is not supported in your version of Node"); |
| 21 | console.error("See more info at https://github.com/ashtuchkin/iconv-lite/wiki/Node-v4-compatibility"); |
| 22 | return; |
| 23 | } |
| 24 | |
| 25 | var nodeNativeEncodings = { |
| 26 | 'hex': true, 'utf8': true, 'utf-8': true, 'ascii': true, 'binary': true, |
| 27 | 'base64': true, 'ucs2': true, 'ucs-2': true, 'utf16le': true, 'utf-16le': true, |
| 28 | }; |
| 29 | |
| 30 | Buffer.isNativeEncoding = function(enc) { |
| 31 | return enc && nodeNativeEncodings[enc.toLowerCase()]; |
| 32 | } |
| 33 | |
| 34 | // -- SlowBuffer ----------------------------------------------------------- |
| 35 | var SlowBuffer = require('buffer').SlowBuffer; |
| 36 | |
| 37 | original.SlowBufferToString = SlowBuffer.prototype.toString; |
| 38 | SlowBuffer.prototype.toString = function(encoding, start, end) { |
| 39 | encoding = String(encoding || 'utf8').toLowerCase(); |
| 40 | |
| 41 | // Use native conversion when possible |
| 42 | if (Buffer.isNativeEncoding(encoding)) |
| 43 | return original.SlowBufferToString.call(this, encoding, start, end); |
| 44 | |
| 45 | // Otherwise, use our decoding method. |
| 46 | if (typeof start == 'undefined') start = 0; |
| 47 | if (typeof end == 'undefined') end = this.length; |
| 48 | return iconv.decode(this.slice(start, end), encoding); |
| 49 | } |
| 50 | |
| 51 | original.SlowBufferWrite = SlowBuffer.prototype.write; |
| 52 | SlowBuffer.prototype.write = function(string, offset, length, encoding) { |
| 53 | // Support both (string, offset, length, encoding) |
| 54 | // and the legacy (string, encoding, offset, length) |
| 55 | if (isFinite(offset)) { |
| 56 | if (!isFinite(length)) { |
| 57 | encoding = length; |
| 58 | length = undefined; |
| 59 | } |
| 60 | } else { // legacy |
| 61 | var swap = encoding; |
| 62 | encoding = offset; |
| 63 | offset = length; |
| 64 | length = swap; |
| 65 | } |
| 66 | |
| 67 | offset = +offset || 0; |
| 68 | var remaining = this.length - offset; |
| 69 | if (!length) { |
| 70 | length = remaining; |
| 71 | } else { |
| 72 | length = +length; |
| 73 | if (length > remaining) { |
| 74 | length = remaining; |
| 75 | } |
| 76 | } |
| 77 | encoding = String(encoding || 'utf8').toLowerCase(); |
| 78 | |
| 79 | // Use native conversion when possible |
| 80 | if (Buffer.isNativeEncoding(encoding)) |
| 81 | return original.SlowBufferWrite.call(this, string, offset, length, encoding); |
| 82 | |
| 83 | if (string.length > 0 && (length < 0 || offset < 0)) |
| 84 | throw new RangeError('attempt to write beyond buffer bounds'); |
| 85 | |
| 86 | // Otherwise, use our encoding method. |
| 87 | var buf = iconv.encode(string, encoding); |
| 88 | if (buf.length < length) length = buf.length; |
| 89 | buf.copy(this, offset, 0, length); |
| 90 | return length; |
| 91 | } |
| 92 | |
| 93 | // -- Buffer --------------------------------------------------------------- |
| 94 | |
| 95 | original.BufferIsEncoding = Buffer.isEncoding; |
| 96 | Buffer.isEncoding = function(encoding) { |
| 97 | return Buffer.isNativeEncoding(encoding) || iconv.encodingExists(encoding); |
| 98 | } |
| 99 | |
| 100 | original.BufferByteLength = Buffer.byteLength; |
| 101 | Buffer.byteLength = SlowBuffer.byteLength = function(str, encoding) { |
| 102 | encoding = String(encoding || 'utf8').toLowerCase(); |
| 103 | |
| 104 | // Use native conversion when possible |
| 105 | if (Buffer.isNativeEncoding(encoding)) |
| 106 | return original.BufferByteLength.call(this, str, encoding); |
| 107 | |
| 108 | // Slow, I know, but we don't have a better way yet. |
| 109 | return iconv.encode(str, encoding).length; |
| 110 | } |
| 111 | |
| 112 | original.BufferToString = Buffer.prototype.toString; |
| 113 | Buffer.prototype.toString = function(encoding, start, end) { |
| 114 | encoding = String(encoding || 'utf8').toLowerCase(); |
| 115 | |
| 116 | // Use native conversion when possible |
| 117 | if (Buffer.isNativeEncoding(encoding)) |
| 118 | return original.BufferToString.call(this, encoding, start, end); |
| 119 | |
| 120 | // Otherwise, use our decoding method. |
| 121 | if (typeof start == 'undefined') start = 0; |
| 122 | if (typeof end == 'undefined') end = this.length; |
| 123 | return iconv.decode(this.slice(start, end), encoding); |
| 124 | } |
| 125 | |
| 126 | original.BufferWrite = Buffer.prototype.write; |
| 127 | Buffer.prototype.write = function(string, offset, length, encoding) { |
| 128 | var _offset = offset, _length = length, _encoding = encoding; |
| 129 | // Support both (string, offset, length, encoding) |
| 130 | // and the legacy (string, encoding, offset, length) |
| 131 | if (isFinite(offset)) { |
| 132 | if (!isFinite(length)) { |
| 133 | encoding = length; |
| 134 | length = undefined; |
| 135 | } |
| 136 | } else { // legacy |
| 137 | var swap = encoding; |
| 138 | encoding = offset; |
| 139 | offset = length; |
| 140 | length = swap; |
| 141 | } |
| 142 | |
| 143 | encoding = String(encoding || 'utf8').toLowerCase(); |
| 144 | |
| 145 | // Use native conversion when possible |
| 146 | if (Buffer.isNativeEncoding(encoding)) |
| 147 | return original.BufferWrite.call(this, string, _offset, _length, _encoding); |
| 148 | |
| 149 | offset = +offset || 0; |
| 150 | var remaining = this.length - offset; |
| 151 | if (!length) { |
| 152 | length = remaining; |
| 153 | } else { |
| 154 | length = +length; |
| 155 | if (length > remaining) { |
| 156 | length = remaining; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | if (string.length > 0 && (length < 0 || offset < 0)) |
| 161 | throw new RangeError('attempt to write beyond buffer bounds'); |
| 162 | |
| 163 | // Otherwise, use our encoding method. |
| 164 | var buf = iconv.encode(string, encoding); |
| 165 | if (buf.length < length) length = buf.length; |
| 166 | buf.copy(this, offset, 0, length); |
| 167 | return length; |
| 168 | |
| 169 | // TODO: Set _charsWritten. |
| 170 | } |
| 171 | |
| 172 | |
| 173 | // -- Readable ------------------------------------------------------------- |
| 174 | if (iconv.supportsStreams) { |
| 175 | var Readable = require('stream').Readable; |
| 176 | |
| 177 | original.ReadableSetEncoding = Readable.prototype.setEncoding; |
| 178 | Readable.prototype.setEncoding = function setEncoding(enc, options) { |
| 179 | // Use our own decoder, it has the same interface. |
| 180 | // We cannot use original function as it doesn't handle BOM-s. |
| 181 | this._readableState.decoder = iconv.getDecoder(enc, options); |
| 182 | this._readableState.encoding = enc; |
| 183 | } |
| 184 | |
| 185 | Readable.prototype.collect = iconv._collect; |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | // Remove iconv-lite Node primitive extensions. |
| 190 | iconv.undoExtendNodeEncodings = function undoExtendNodeEncodings() { |
| 191 | if (!iconv.supportsNodeEncodingsExtension) |
| 192 | return; |
| 193 | if (!original) |
| 194 | throw new Error("require('iconv-lite').undoExtendNodeEncodings(): Nothing to undo; extendNodeEncodings() is not called.") |
| 195 | |
| 196 | delete Buffer.isNativeEncoding; |
| 197 | |
| 198 | var SlowBuffer = require('buffer').SlowBuffer; |
| 199 | |
| 200 | SlowBuffer.prototype.toString = original.SlowBufferToString; |
| 201 | SlowBuffer.prototype.write = original.SlowBufferWrite; |
| 202 | |
| 203 | Buffer.isEncoding = original.BufferIsEncoding; |
| 204 | Buffer.byteLength = original.BufferByteLength; |
| 205 | Buffer.prototype.toString = original.BufferToString; |
| 206 | Buffer.prototype.write = original.BufferWrite; |
| 207 | |
| 208 | if (iconv.supportsStreams) { |
| 209 | var Readable = require('stream').Readable; |
| 210 | |
| 211 | Readable.prototype.setEncoding = original.ReadableSetEncoding; |
| 212 | delete Readable.prototype.collect; |
| 213 | } |
| 214 | |
| 215 | original = undefined; |
| 216 | } |
| 217 | } |