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-rw-r--r--node_modules/string_decoder/lib/string_decoder.js296
1 files changed, 296 insertions, 0 deletions
diff --git a/node_modules/string_decoder/lib/string_decoder.js b/node_modules/string_decoder/lib/string_decoder.js
new file mode 100644
index 0000000..2e89e63
--- /dev/null
+++ b/node_modules/string_decoder/lib/string_decoder.js
@@ -0,0 +1,296 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// 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.
+
+'use strict';
+
+/*<replacement>*/
+
+var Buffer = require('safe-buffer').Buffer;
+/*</replacement>*/
+
+var isEncoding = Buffer.isEncoding || function (encoding) {
+ encoding = '' + encoding;
+ switch (encoding && encoding.toLowerCase()) {
+ case 'hex':case 'utf8':case 'utf-8':case 'ascii':case 'binary':case 'base64':case 'ucs2':case 'ucs-2':case 'utf16le':case 'utf-16le':case 'raw':
+ return true;
+ default:
+ return false;
+ }
+};
+
+function _normalizeEncoding(enc) {
+ if (!enc) return 'utf8';
+ var retried;
+ while (true) {
+ switch (enc) {
+ case 'utf8':
+ case 'utf-8':
+ return 'utf8';
+ case 'ucs2':
+ case 'ucs-2':
+ case 'utf16le':
+ case 'utf-16le':
+ return 'utf16le';
+ case 'latin1':
+ case 'binary':
+ return 'latin1';
+ case 'base64':
+ case 'ascii':
+ case 'hex':
+ return enc;
+ default:
+ if (retried) return; // undefined
+ enc = ('' + enc).toLowerCase();
+ retried = true;
+ }
+ }
+};
+
+// Do not cache `Buffer.isEncoding` when checking encoding names as some
+// modules monkey-patch it to support additional encodings
+function normalizeEncoding(enc) {
+ var nenc = _normalizeEncoding(enc);
+ if (typeof nenc !== 'string' && (Buffer.isEncoding === isEncoding || !isEncoding(enc))) throw new Error('Unknown encoding: ' + enc);
+ return nenc || enc;
+}
+
+// StringDecoder provides an interface for efficiently splitting a series of
+// buffers into a series of JS strings without breaking apart multi-byte
+// characters.
+exports.StringDecoder = StringDecoder;
+function StringDecoder(encoding) {
+ this.encoding = normalizeEncoding(encoding);
+ var nb;
+ switch (this.encoding) {
+ case 'utf16le':
+ this.text = utf16Text;
+ this.end = utf16End;
+ nb = 4;
+ break;
+ case 'utf8':
+ this.fillLast = utf8FillLast;
+ nb = 4;
+ break;
+ case 'base64':
+ this.text = base64Text;
+ this.end = base64End;
+ nb = 3;
+ break;
+ default:
+ this.write = simpleWrite;
+ this.end = simpleEnd;
+ return;
+ }
+ this.lastNeed = 0;
+ this.lastTotal = 0;
+ this.lastChar = Buffer.allocUnsafe(nb);
+}
+
+StringDecoder.prototype.write = function (buf) {
+ if (buf.length === 0) return '';
+ var r;
+ var i;
+ if (this.lastNeed) {
+ r = this.fillLast(buf);
+ if (r === undefined) return '';
+ i = this.lastNeed;
+ this.lastNeed = 0;
+ } else {
+ i = 0;
+ }
+ if (i < buf.length) return r ? r + this.text(buf, i) : this.text(buf, i);
+ return r || '';
+};
+
+StringDecoder.prototype.end = utf8End;
+
+// Returns only complete characters in a Buffer
+StringDecoder.prototype.text = utf8Text;
+
+// Attempts to complete a partial non-UTF-8 character using bytes from a Buffer
+StringDecoder.prototype.fillLast = function (buf) {
+ if (this.lastNeed <= buf.length) {
+ buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, this.lastNeed);
+ return this.lastChar.toString(this.encoding, 0, this.lastTotal);
+ }
+ buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, buf.length);
+ this.lastNeed -= buf.length;
+};
+
+// Checks the type of a UTF-8 byte, whether it's ASCII, a leading byte, or a
+// continuation byte. If an invalid byte is detected, -2 is returned.
+function utf8CheckByte(byte) {
+ if (byte <= 0x7F) return 0;else if (byte >> 5 === 0x06) return 2;else if (byte >> 4 === 0x0E) return 3;else if (byte >> 3 === 0x1E) return 4;
+ return byte >> 6 === 0x02 ? -1 : -2;
+}
+
+// Checks at most 3 bytes at the end of a Buffer in order to detect an
+// incomplete multi-byte UTF-8 character. The total number of bytes (2, 3, or 4)
+// needed to complete the UTF-8 character (if applicable) are returned.
+function utf8CheckIncomplete(self, buf, i) {
+ var j = buf.length - 1;
+ if (j < i) return 0;
+ var nb = utf8CheckByte(buf[j]);
+ if (nb >= 0) {
+ if (nb > 0) self.lastNeed = nb - 1;
+ return nb;
+ }
+ if (--j < i || nb === -2) return 0;
+ nb = utf8CheckByte(buf[j]);
+ if (nb >= 0) {
+ if (nb > 0) self.lastNeed = nb - 2;
+ return nb;
+ }
+ if (--j < i || nb === -2) return 0;
+ nb = utf8CheckByte(buf[j]);
+ if (nb >= 0) {
+ if (nb > 0) {
+ if (nb === 2) nb = 0;else self.lastNeed = nb - 3;
+ }
+ return nb;
+ }
+ return 0;
+}
+
+// Validates as many continuation bytes for a multi-byte UTF-8 character as
+// needed or are available. If we see a non-continuation byte where we expect
+// one, we "replace" the validated continuation bytes we've seen so far with
+// a single UTF-8 replacement character ('\ufffd'), to match v8's UTF-8 decoding
+// behavior. The continuation byte check is included three times in the case
+// where all of the continuation bytes for a character exist in the same buffer.
+// It is also done this way as a slight performance increase instead of using a
+// loop.
+function utf8CheckExtraBytes(self, buf, p) {
+ if ((buf[0] & 0xC0) !== 0x80) {
+ self.lastNeed = 0;
+ return '\ufffd';
+ }
+ if (self.lastNeed > 1 && buf.length > 1) {
+ if ((buf[1] & 0xC0) !== 0x80) {
+ self.lastNeed = 1;
+ return '\ufffd';
+ }
+ if (self.lastNeed > 2 && buf.length > 2) {
+ if ((buf[2] & 0xC0) !== 0x80) {
+ self.lastNeed = 2;
+ return '\ufffd';
+ }
+ }
+ }
+}
+
+// Attempts to complete a multi-byte UTF-8 character using bytes from a Buffer.
+function utf8FillLast(buf) {
+ var p = this.lastTotal - this.lastNeed;
+ var r = utf8CheckExtraBytes(this, buf, p);
+ if (r !== undefined) return r;
+ if (this.lastNeed <= buf.length) {
+ buf.copy(this.lastChar, p, 0, this.lastNeed);
+ return this.lastChar.toString(this.encoding, 0, this.lastTotal);
+ }
+ buf.copy(this.lastChar, p, 0, buf.length);
+ this.lastNeed -= buf.length;
+}
+
+// Returns all complete UTF-8 characters in a Buffer. If the Buffer ended on a
+// partial character, the character's bytes are buffered until the required
+// number of bytes are available.
+function utf8Text(buf, i) {
+ var total = utf8CheckIncomplete(this, buf, i);
+ if (!this.lastNeed) return buf.toString('utf8', i);
+ this.lastTotal = total;
+ var end = buf.length - (total - this.lastNeed);
+ buf.copy(this.lastChar, 0, end);
+ return buf.toString('utf8', i, end);
+}
+
+// For UTF-8, a replacement character is added when ending on a partial
+// character.
+function utf8End(buf) {
+ var r = buf && buf.length ? this.write(buf) : '';
+ if (this.lastNeed) return r + '\ufffd';
+ return r;
+}
+
+// UTF-16LE typically needs two bytes per character, but even if we have an even
+// number of bytes available, we need to check if we end on a leading/high
+// surrogate. In that case, we need to wait for the next two bytes in order to
+// decode the last character properly.
+function utf16Text(buf, i) {
+ if ((buf.length - i) % 2 === 0) {
+ var r = buf.toString('utf16le', i);
+ if (r) {
+ var c = r.charCodeAt(r.length - 1);
+ if (c >= 0xD800 && c <= 0xDBFF) {
+ this.lastNeed = 2;
+ this.lastTotal = 4;
+ this.lastChar[0] = buf[buf.length - 2];
+ this.lastChar[1] = buf[buf.length - 1];
+ return r.slice(0, -1);
+ }
+ }
+ return r;
+ }
+ this.lastNeed = 1;
+ this.lastTotal = 2;
+ this.lastChar[0] = buf[buf.length - 1];
+ return buf.toString('utf16le', i, buf.length - 1);
+}
+
+// For UTF-16LE we do not explicitly append special replacement characters if we
+// end on a partial character, we simply let v8 handle that.
+function utf16End(buf) {
+ var r = buf && buf.length ? this.write(buf) : '';
+ if (this.lastNeed) {
+ var end = this.lastTotal - this.lastNeed;
+ return r + this.lastChar.toString('utf16le', 0, end);
+ }
+ return r;
+}
+
+function base64Text(buf, i) {
+ var n = (buf.length - i) % 3;
+ if (n === 0) return buf.toString('base64', i);
+ this.lastNeed = 3 - n;
+ this.lastTotal = 3;
+ if (n === 1) {
+ this.lastChar[0] = buf[buf.length - 1];
+ } else {
+ this.lastChar[0] = buf[buf.length - 2];
+ this.lastChar[1] = buf[buf.length - 1];
+ }
+ return buf.toString('base64', i, buf.length - n);
+}
+
+function base64End(buf) {
+ var r = buf && buf.length ? this.write(buf) : '';
+ if (this.lastNeed) return r + this.lastChar.toString('base64', 0, 3 - this.lastNeed);
+ return r;
+}
+
+// Pass bytes on through for single-byte encodings (e.g. ascii, latin1, hex)
+function simpleWrite(buf) {
+ return buf.toString(this.encoding);
+}
+
+function simpleEnd(buf) {
+ return buf && buf.length ? this.write(buf) : '';
+} \ No newline at end of file
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