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ralexrdz/shp-to-json.browser.js

Created December 7, 2023 01:12
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shp-to-json.browser.js
class Properties {
constructor (tableBuffer) {
this.tableBuffer = tableBuffer;
this.properties = [];
if (tableBuffer === null) return
this.tableHeaderLength = tableBuffer.readInt16LE(8);
this.recordLength = tableBuffer.readInt16LE(10);
const fieldDescriptors = tableBuffer.slice(32, this.tableHeaderLength - 2);
let start = 0;
while (start < fieldDescriptors.length) {
const field = fieldDescriptors.slice(start, start + 32);
const fieldName = field.slice(0, 11).toString('utf8').replace(/[\u0000]+$/, '');
const fieldLength = field.readUInt8(16);
const fieldType = field.toString('utf8', 11, 15).replace(/[\u0000]+$/, '');
this.properties.push({fieldName, fieldType, fieldLength});
start += 32;
}
this.numberProperties = this.properties.length;
}
getRowProperties (index) {
const outProperties = {};
if (this.tableBuffer === null) return outProperties
const recordStart = this.tableHeaderLength + (index * this.recordLength) + 1;
let usedFieldLength = 0;
for (let i = 0; i < this.numberProperties; i++) {
const p = this.properties[i];
const rowData = this.tableBuffer.toString('utf8', recordStart + usedFieldLength, recordStart + usedFieldLength + p.fieldLength).replace(/^\x20+|\x20+$/g, '');
if (p.fieldType === 'N') {
let v = Number(rowData);
if (Number.isNaN(v)) v = null;
outProperties[p.fieldName] = v;
} else {
outProperties[p.fieldName] = rowData;
}
usedFieldLength += p.fieldLength;
}
return outProperties
}
}
function createPoint (recordContent, hasZ) {
const p = {
type: "Point",
coordinates: [recordContent.readDoubleLE(4), recordContent.readDoubleLE(12)]
};
if (hasZ) p.coordinates.push(recordContent.readDoubleLE(20));
return p
}
function createPolyline (recordContent, hasZ) {
const numParts = recordContent.readInt16LE(36);
const numPoints = recordContent.readInt16LE(40);
const startingIndices = [];
for (let i = 0; i < numParts; i++) {
startingIndices.push(recordContent.readInt32LE(44 + 4 * i));
}
let totalVisited = 0;
const pointsSlice = recordContent.slice(44 + (4 * (numParts - 1)));
let outPolylines = [];
for (let i = 0; i < startingIndices.length; i++) {
const finishPoint = i === startingIndices.length - 1 ? numPoints : startingIndices[i + 1];
const numPointsInRing = finishPoint - startingIndices[i];
const line = [];
for (let ii = 0; ii < numPointsInRing; ii++) {
const coords = [
pointsSlice.readDoubleLE(totalVisited * 16 + 4),
pointsSlice.readDoubleLE(totalVisited * 16 + 12)
];
if (hasZ) coords.push(pointsSlice.readDoubleLE((totalVisited * 16) + 20));
line.push(coords);
totalVisited++;
}
outPolylines.push(line);
}
const outType = outPolylines.length === 1 ? 'LineString' : 'MultiLineString';
const outCoords = outPolylines.length === 1 ? outPolylines[0] : outPolylines;
const out = {
type: outType,
coordinates: outCoords
};
return out
}
function createPolygon (recordContent, hasZ) {
const numParts = recordContent.readInt16LE(36);
const numPoints = recordContent.readInt16LE(40);
const startingIndices = [];
for (let i = 0; i < numParts; i++) {
startingIndices.push(recordContent.readInt32LE(44 + 4 * i));
}
let totalVisited = 0;
const pointsSlice = recordContent.slice(44 + (4 * (numParts - 1)));
let polygon = [calculateRing(0)];
const multiPoly = [polygon];
for (let i = 1; i < startingIndices.length; i++) {
const ring = calculateRing(i);
// Outer rings are clockwise
if (ringClockwise(ring)) {
polygon = [ring];
multiPoly.push(polygon);
} else { //This is a hole
polygon.push(ring);
}
}
return {
type: multiPoly.length === 1 ? 'Polygon' : 'MultiPolygon',
coordinates: multiPoly.length === 1 ? polygon : multiPoly
}
function calculateRing (i) {
const finishPoint = i === startingIndices.length - 1 ? numPoints : startingIndices[i + 1];
const numPointsInRing = finishPoint - startingIndices[i];
const ring = [];
for (let ii = 0; ii < numPointsInRing; ii++) {
const coords = [
pointsSlice.readDoubleLE((totalVisited * 16) + 4),
pointsSlice.readDoubleLE((totalVisited * 16) + 12)
];
if (hasZ) coords.push(pointsSlice.readDoubleLE((totalVisited * 16) + 20));
ring.push(coords);
totalVisited++;
}
return ring
}
}
function ringClockwise (ring) {
let sum = 0;
let i = 1;
let prev;
let cur;
const len = ring.length;
while (i < len) {
prev = cur || ring[0];
cur = ring[i];
sum += ((cur[0] - prev[0]) * (cur[1] + prev[1]));
i++;
}
return sum > 0;
}
function createMultiPoint (recordContent) {
const coordinates = [];
const numPoints = recordContent.readInt16LE(36);
for (let i = 0; i < numPoints; i++) {
coordinates.push([recordContent.readDoubleLE(36 + (16 * i) + 4), recordContent.readDoubleLE(36 + (16 * i) + 12)]);
}
return {
"type": "MultiPoint",
"coordinates": coordinates
}
}
function createCommonjsModule(fn) {
var module = { exports: {} };
return fn(module, module.exports), module.exports;
}
var byteLength_1 = byteLength;
var toByteArray_1 = toByteArray;
var fromByteArray_1 = fromByteArray;
var lookup = [];
var revLookup = [];
var Arr = typeof Uint8Array !== 'undefined' ? Uint8Array : Array;
var code = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
for (var i = 0, len = code.length; i < len; ++i) {
lookup[i] = code[i];
revLookup[code.charCodeAt(i)] = i;
}
// Support decoding URL-safe base64 strings, as Node.js does.
// See: https://en.wikipedia.org/wiki/Base64#URL_applications
revLookup['-'.charCodeAt(0)] = 62;
revLookup['_'.charCodeAt(0)] = 63;
function getLens (b64) {
var len = b64.length;
if (len % 4 > 0) {
throw new Error('Invalid string. Length must be a multiple of 4')
}
// Trim off extra bytes after placeholder bytes are found
// See: https://github.com/beatgammit/base64-js/issues/42
var validLen = b64.indexOf('=');
if (validLen === -1) validLen = len;
var placeHoldersLen = validLen === len
? 0
: 4 - (validLen % 4);
return [validLen, placeHoldersLen]
}
// base64 is 4/3 + up to two characters of the original data
function byteLength (b64) {
var lens = getLens(b64);
var validLen = lens[0];
var placeHoldersLen = lens[1];
return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen
}
function _byteLength (b64, validLen, placeHoldersLen) {
return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen
}
function toByteArray (b64) {
var tmp;
var lens = getLens(b64);
var validLen = lens[0];
var placeHoldersLen = lens[1];
var arr = new Arr(_byteLength(b64, validLen, placeHoldersLen));
var curByte = 0;
// if there are placeholders, only get up to the last complete 4 chars
var len = placeHoldersLen > 0
? validLen - 4
: validLen;
var i;
for (i = 0; i < len; i += 4) {
tmp =
(revLookup[b64.charCodeAt(i)] << 18) |
(revLookup[b64.charCodeAt(i + 1)] << 12) |
(revLookup[b64.charCodeAt(i + 2)] << 6) |
revLookup[b64.charCodeAt(i + 3)];
arr[curByte++] = (tmp >> 16) & 0xFF;
arr[curByte++] = (tmp >> 8) & 0xFF;
arr[curByte++] = tmp & 0xFF;
}
if (placeHoldersLen === 2) {
tmp =
(revLookup[b64.charCodeAt(i)] << 2) |
(revLookup[b64.charCodeAt(i + 1)] >> 4);
arr[curByte++] = tmp & 0xFF;
}
if (placeHoldersLen === 1) {
tmp =
(revLookup[b64.charCodeAt(i)] << 10) |
(revLookup[b64.charCodeAt(i + 1)] << 4) |
(revLookup[b64.charCodeAt(i + 2)] >> 2);
arr[curByte++] = (tmp >> 8) & 0xFF;
arr[curByte++] = tmp & 0xFF;
}
return arr
}
function tripletToBase64 (num) {
return lookup[num >> 18 & 0x3F] +
lookup[num >> 12 & 0x3F] +
lookup[num >> 6 & 0x3F] +
lookup[num & 0x3F]
}
function encodeChunk (uint8, start, end) {
var tmp;
var output = [];
for (var i = start; i < end; i += 3) {
tmp =
((uint8[i] << 16) & 0xFF0000) +
((uint8[i + 1] << 8) & 0xFF00) +
(uint8[i + 2] & 0xFF);
output.push(tripletToBase64(tmp));
}
return output.join('')
}
function fromByteArray (uint8) {
var tmp;
var len = uint8.length;
var extraBytes = len % 3; // if we have 1 byte left, pad 2 bytes
var parts = [];
var maxChunkLength = 16383; // must be multiple of 3
// go through the array every three bytes, we'll deal with trailing stuff later
for (var i = 0, len2 = len - extraBytes; i < len2; i += maxChunkLength) {
parts.push(encodeChunk(uint8, i, (i + maxChunkLength) > len2 ? len2 : (i + maxChunkLength)));
}
// pad the end with zeros, but make sure to not forget the extra bytes
if (extraBytes === 1) {
tmp = uint8[len - 1];
parts.push(
lookup[tmp >> 2] +
lookup[(tmp << 4) & 0x3F] +
'=='
);
} else if (extraBytes === 2) {
tmp = (uint8[len - 2] << 8) + uint8[len - 1];
parts.push(
lookup[tmp >> 10] +
lookup[(tmp >> 4) & 0x3F] +
lookup[(tmp << 2) & 0x3F] +
'='
);
}
return parts.join('')
}
var base64Js = {
byteLength: byteLength_1,
toByteArray: toByteArray_1,
fromByteArray: fromByteArray_1
};
/*! ieee754. BSD-3-Clause License. Feross Aboukhadijeh <https://feross.org/opensource> */
var read = function (buffer, offset, isLE, mLen, nBytes) {
var e, m;
var eLen = (nBytes * 8) - mLen - 1;
var eMax = (1 << eLen) - 1;
var eBias = eMax >> 1;
var nBits = -7;
var i = isLE ? (nBytes - 1) : 0;
var d = isLE ? -1 : 1;
var s = buffer[offset + i];
i += d;
e = s & ((1 << (-nBits)) - 1);
s >>= (-nBits);
nBits += eLen;
for (; nBits > 0; e = (e * 256) + buffer[offset + i], i += d, nBits -= 8) {}
m = e & ((1 << (-nBits)) - 1);
e >>= (-nBits);
nBits += mLen;
for (; nBits > 0; m = (m * 256) + buffer[offset + i], i += d, nBits -= 8) {}
if (e === 0) {
e = 1 - eBias;
} else if (e === eMax) {
return m ? NaN : ((s ? -1 : 1) * Infinity)
} else {
m = m + Math.pow(2, mLen);
e = e - eBias;
}
return (s ? -1 : 1) * m * Math.pow(2, e - mLen)
};
var write = function (buffer, value, offset, isLE, mLen, nBytes) {
var e, m, c;
var eLen = (nBytes * 8) - mLen - 1;
var eMax = (1 << eLen) - 1;
var eBias = eMax >> 1;
var rt = (mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0);
var i = isLE ? 0 : (nBytes - 1);
var d = isLE ? 1 : -1;
var s = value < 0 || (value === 0 && 1 / value < 0) ? 1 : 0;
value = Math.abs(value);
if (isNaN(value) || value === Infinity) {
m = isNaN(value) ? 1 : 0;
e = eMax;
} else {
e = Math.floor(Math.log(value) / Math.LN2);
if (value * (c = Math.pow(2, -e)) < 1) {
e--;
c *= 2;
}
if (e + eBias >= 1) {
value += rt / c;
} else {
value += rt * Math.pow(2, 1 - eBias);
}
if (value * c >= 2) {
e++;
c /= 2;
}
if (e + eBias >= eMax) {
m = 0;
e = eMax;
} else if (e + eBias >= 1) {
m = ((value * c) - 1) * Math.pow(2, mLen);
e = e + eBias;
} else {
m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen);
e = 0;
}
}
for (; mLen >= 8; buffer[offset + i] = m & 0xff, i += d, m /= 256, mLen -= 8) {}
e = (e << mLen) | m;
eLen += mLen;
for (; eLen > 0; buffer[offset + i] = e & 0xff, i += d, e /= 256, eLen -= 8) {}
buffer[offset + i - d] |= s * 128;
};
var ieee754 = {
read: read,
write: write
};
/*!
* The buffer module from node.js, for the browser.
*
* @author Feross Aboukhadijeh <https://feross.org>
* @license MIT
*/
var buffer = createCommonjsModule(function (module, exports) {
const customInspectSymbol =
(typeof Symbol === 'function' && typeof Symbol['for'] === 'function') // eslint-disable-line dot-notation
? Symbol['for']('nodejs.util.inspect.custom') // eslint-disable-line dot-notation
: null;
exports.Buffer = Buffer;
exports.SlowBuffer = SlowBuffer;
exports.INSPECT_MAX_BYTES = 50;
const K_MAX_LENGTH = 0x7fffffff;
exports.kMaxLength = K_MAX_LENGTH;
/**
* If `Buffer.TYPED_ARRAY_SUPPORT`:
* === true Use Uint8Array implementation (fastest)
* === false Print warning and recommend using `buffer` v4.x which has an Object
* implementation (most compatible, even IE6)
*
* Browsers that support typed arrays are IE 10+, Firefox 4+, Chrome 7+, Safari 5.1+,
* Opera 11.6+, iOS 4.2+.
*
* We report that the browser does not support typed arrays if the are not subclassable
* using __proto__. Firefox 4-29 lacks support for adding new properties to `Uint8Array`
* (See: https://bugzilla.mozilla.org/show_bug.cgi?id=695438). IE 10 lacks support
* for __proto__ and has a buggy typed array implementation.
*/
Buffer.TYPED_ARRAY_SUPPORT = typedArraySupport();
if (!Buffer.TYPED_ARRAY_SUPPORT && typeof console !== 'undefined' &&
typeof console.error === 'function') {
console.error(
'This browser lacks typed array (Uint8Array) support which is required by ' +
'`buffer` v5.x. Use `buffer` v4.x if you require old browser support.'
);
}
function typedArraySupport () {
// Can typed array instances can be augmented?
try {
const arr = new Uint8Array(1);
const proto = { foo: function () { return 42 } };
Object.setPrototypeOf(proto, Uint8Array.prototype);
Object.setPrototypeOf(arr, proto);
return arr.foo() === 42
} catch (e) {
return false
}
}
Object.defineProperty(Buffer.prototype, 'parent', {
enumerable: true,
get: function () {
if (!Buffer.isBuffer(this)) return undefined
return this.buffer
}
});
Object.defineProperty(Buffer.prototype, 'offset', {
enumerable: true,
get: function () {
if (!Buffer.isBuffer(this)) return undefined
return this.byteOffset
}
});
function createBuffer (length) {
if (length > K_MAX_LENGTH) {
throw new RangeError('The value "' + length + '" is invalid for option "size"')
}
// Return an augmented `Uint8Array` instance
const buf = new Uint8Array(length);
Object.setPrototypeOf(buf, Buffer.prototype);
return buf
}
/**
* The Buffer constructor returns instances of `Uint8Array` that have their
* prototype changed to `Buffer.prototype`. Furthermore, `Buffer` is a subclass of
* `Uint8Array`, so the returned instances will have all the node `Buffer` methods
* and the `Uint8Array` methods. Square bracket notation works as expected -- it
* returns a single octet.
*
* The `Uint8Array` prototype remains unmodified.
*/
function Buffer (arg, encodingOrOffset, length) {
// Common case.
if (typeof arg === 'number') {
if (typeof encodingOrOffset === 'string') {
throw new TypeError(
'The "string" argument must be of type string. Received type number'
)
}
return allocUnsafe(arg)
}
return from(arg, encodingOrOffset, length)
}
Buffer.poolSize = 8192; // not used by this implementation
function from (value, encodingOrOffset, length) {
if (typeof value === 'string') {
return fromString(value, encodingOrOffset)
}
if (ArrayBuffer.isView(value)) {
return fromArrayView(value)
}
if (value == null) {
throw new TypeError(
'The first argument must be one of type string, Buffer, ArrayBuffer, Array, ' +
'or Array-like Object. Received type ' + (typeof value)
)
}
if (isInstance(value, ArrayBuffer) ||
(value && isInstance(value.buffer, ArrayBuffer))) {
return fromArrayBuffer(value, encodingOrOffset, length)
}
if (typeof SharedArrayBuffer !== 'undefined' &&
(isInstance(value, SharedArrayBuffer) ||
(value && isInstance(value.buffer, SharedArrayBuffer)))) {
return fromArrayBuffer(value, encodingOrOffset, length)
}
if (typeof value === 'number') {
throw new TypeError(
'The "value" argument must not be of type number. Received type number'
)
}
const valueOf = value.valueOf && value.valueOf();
if (valueOf != null && valueOf !== value) {
return Buffer.from(valueOf, encodingOrOffset, length)
}
const b = fromObject(value);
if (b) return b
if (typeof Symbol !== 'undefined' && Symbol.toPrimitive != null &&
typeof value[Symbol.toPrimitive] === 'function') {
return Buffer.from(value[Symbol.toPrimitive]('string'), encodingOrOffset, length)
}
throw new TypeError(
'The first argument must be one of type string, Buffer, ArrayBuffer, Array, ' +
'or Array-like Object. Received type ' + (typeof value)
)
}
/**
* Functionally equivalent to Buffer(arg, encoding) but throws a TypeError
* if value is a number.
* Buffer.from(str[, encoding])
* Buffer.from(array)
* Buffer.from(buffer)
* Buffer.from(arrayBuffer[, byteOffset[, length]])
**/
Buffer.from = function (value, encodingOrOffset, length) {
return from(value, encodingOrOffset, length)
};
// Note: Change prototype *after* Buffer.from is defined to workaround Chrome bug:
// https://github.com/feross/buffer/pull/148
Object.setPrototypeOf(Buffer.prototype, Uint8Array.prototype);
Object.setPrototypeOf(Buffer, Uint8Array);
function assertSize (size) {
if (typeof size !== 'number') {
throw new TypeError('"size" argument must be of type number')
} else if (size < 0) {
throw new RangeError('The value "' + size + '" is invalid for option "size"')
}
}
function alloc (size, fill, encoding) {
assertSize(size);
if (size <= 0) {
return createBuffer(size)
}
if (fill !== undefined) {
// Only pay attention to encoding if it's a string. This
// prevents accidentally sending in a number that would
// be interpreted as a start offset.
return typeof encoding === 'string'
? createBuffer(size).fill(fill, encoding)
: createBuffer(size).fill(fill)
}
return createBuffer(size)
}
/**
* Creates a new filled Buffer instance.
* alloc(size[, fill[, encoding]])
**/
Buffer.alloc = function (size, fill, encoding) {
return alloc(size, fill, encoding)
};
function allocUnsafe (size) {
assertSize(size);
return createBuffer(size < 0 ? 0 : checked(size) | 0)
}
/**
* Equivalent to Buffer(num), by default creates a non-zero-filled Buffer instance.
* */
Buffer.allocUnsafe = function (size) {
return allocUnsafe(size)
};
/**
* Equivalent to SlowBuffer(num), by default creates a non-zero-filled Buffer instance.
*/
Buffer.allocUnsafeSlow = function (size) {
return allocUnsafe(size)
};
function fromString (string, encoding) {
if (typeof encoding !== 'string' || encoding === '') {
encoding = 'utf8';
}
if (!Buffer.isEncoding(encoding)) {
throw new TypeError('Unknown encoding: ' + encoding)
}
const length = byteLength(string, encoding) | 0;
let buf = createBuffer(length);
const actual = buf.write(string, encoding);
if (actual !== length) {
// Writing a hex string, for example, that contains invalid characters will
// cause everything after the first invalid character to be ignored. (e.g.
// 'abxxcd' will be treated as 'ab')
buf = buf.slice(0, actual);
}
return buf
}
function fromArrayLike (array) {
const length = array.length < 0 ? 0 : checked(array.length) | 0;
const buf = createBuffer(length);
for (let i = 0; i < length; i += 1) {
buf[i] = array[i] & 255;
}
return buf
}
function fromArrayView (arrayView) {
if (isInstance(arrayView, Uint8Array)) {
const copy = new Uint8Array(arrayView);
return fromArrayBuffer(copy.buffer, copy.byteOffset, copy.byteLength)
}
return fromArrayLike(arrayView)
}
function fromArrayBuffer (array, byteOffset, length) {
if (byteOffset < 0 || array.byteLength < byteOffset) {
throw new RangeError('"offset" is outside of buffer bounds')
}
if (array.byteLength < byteOffset + (length || 0)) {
throw new RangeError('"length" is outside of buffer bounds')
}
let buf;
if (byteOffset === undefined && length === undefined) {
buf = new Uint8Array(array);
} else if (length === undefined) {
buf = new Uint8Array(array, byteOffset);
} else {
buf = new Uint8Array(array, byteOffset, length);
}
// Return an augmented `Uint8Array` instance
Object.setPrototypeOf(buf, Buffer.prototype);
return buf
}
function fromObject (obj) {
if (Buffer.isBuffer(obj)) {
const len = checked(obj.length) | 0;
const buf = createBuffer(len);
if (buf.length === 0) {
return buf
}
obj.copy(buf, 0, 0, len);
return buf
}
if (obj.length !== undefined) {
if (typeof obj.length !== 'number' || numberIsNaN(obj.length)) {
return createBuffer(0)
}
return fromArrayLike(obj)
}
if (obj.type === 'Buffer' && Array.isArray(obj.data)) {
return fromArrayLike(obj.data)
}
}
function checked (length) {
// Note: cannot use `length < K_MAX_LENGTH` here because that fails when
// length is NaN (which is otherwise coerced to zero.)
if (length >= K_MAX_LENGTH) {
throw new RangeError('Attempt to allocate Buffer larger than maximum ' +
'size: 0x' + K_MAX_LENGTH.toString(16) + ' bytes')
}
return length | 0
}
function SlowBuffer (length) {
if (+length != length) { // eslint-disable-line eqeqeq
length = 0;
}
return Buffer.alloc(+length)
}
Buffer.isBuffer = function isBuffer (b) {
return b != null && b._isBuffer === true &&
b !== Buffer.prototype // so Buffer.isBuffer(Buffer.prototype) will be false
};
Buffer.compare = function compare (a, b) {
if (isInstance(a, Uint8Array)) a = Buffer.from(a, a.offset, a.byteLength);
if (isInstance(b, Uint8Array)) b = Buffer.from(b, b.offset, b.byteLength);
if (!Buffer.isBuffer(a) || !Buffer.isBuffer(b)) {
throw new TypeError(
'The "buf1", "buf2" arguments must be one of type Buffer or Uint8Array'
)
}
if (a === b) return 0
let x = a.length;
let y = b.length;
for (let i = 0, len = Math.min(x, y); i < len; ++i) {
if (a[i] !== b[i]) {
x = a[i];
y = b[i];
break
}
}
if (x < y) return -1
if (y < x) return 1
return 0
};
Buffer.isEncoding = function isEncoding (encoding) {
switch (String(encoding).toLowerCase()) {
case 'hex':
case 'utf8':
case 'utf-8':
case 'ascii':
case 'latin1':
case 'binary':
case 'base64':
case 'ucs2':
case 'ucs-2':
case 'utf16le':
case 'utf-16le':
return true
default:
return false
}
};
Buffer.concat = function concat (list, length) {
if (!Array.isArray(list)) {
throw new TypeError('"list" argument must be an Array of Buffers')
}
if (list.length === 0) {
return Buffer.alloc(0)
}
let i;
if (length === undefined) {
length = 0;
for (i = 0; i < list.length; ++i) {
length += list[i].length;
}
}
const buffer = Buffer.allocUnsafe(length);
let pos = 0;
for (i = 0; i < list.length; ++i) {
let buf = list[i];
if (isInstance(buf, Uint8Array)) {
if (pos + buf.length > buffer.length) {
if (!Buffer.isBuffer(buf)) buf = Buffer.from(buf);
buf.copy(buffer, pos);
} else {
Uint8Array.prototype.set.call(
buffer,
buf,
pos
);
}
} else if (!Buffer.isBuffer(buf)) {
throw new TypeError('"list" argument must be an Array of Buffers')
} else {
buf.copy(buffer, pos);
}
pos += buf.length;
}
return buffer
};
function byteLength (string, encoding) {
if (Buffer.isBuffer(string)) {
return string.length
}
if (ArrayBuffer.isView(string) || isInstance(string, ArrayBuffer)) {
return string.byteLength
}
if (typeof string !== 'string') {
throw new TypeError(
'The "string" argument must be one of type string, Buffer, or ArrayBuffer. ' +
'Received type ' + typeof string
)
}
const len = string.length;
const mustMatch = (arguments.length > 2 && arguments[2] === true);
if (!mustMatch && len === 0) return 0
// Use a for loop to avoid recursion
let loweredCase = false;
for (;;) {
switch (encoding) {
case 'ascii':
case 'latin1':
case 'binary':
return len
case 'utf8':
case 'utf-8':
return utf8ToBytes(string).length
case 'ucs2':
case 'ucs-2':
case 'utf16le':
case 'utf-16le':
return len * 2
case 'hex':
return len >>> 1
case 'base64':
return base64ToBytes(string).length
default:
if (loweredCase) {
return mustMatch ? -1 : utf8ToBytes(string).length // assume utf8
}
encoding = ('' + encoding).toLowerCase();
loweredCase = true;
}
}
}
Buffer.byteLength = byteLength;
function slowToString (encoding, start, end) {
let loweredCase = false;
// No need to verify that "this.length <= MAX_UINT32" since it's a read-only
// property of a typed array.
// This behaves neither like String nor Uint8Array in that we set start/end
// to their upper/lower bounds if the value passed is out of range.
// undefined is handled specially as per ECMA-262 6th Edition,
// Section 13.3.3.7 Runtime Semantics: KeyedBindingInitialization.
if (start === undefined || start < 0) {
start = 0;
}
// Return early if start > this.length. Done here to prevent potential uint32
// coercion fail below.
if (start > this.length) {
return ''
}
if (end === undefined || end > this.length) {
end = this.length;
}
if (end <= 0) {
return ''
}
// Force coercion to uint32. This will also coerce falsey/NaN values to 0.
end >>>= 0;
start >>>= 0;
if (end <= start) {
return ''
}
if (!encoding) encoding = 'utf8';
while (true) {
switch (encoding) {
case 'hex':
return hexSlice(this, start, end)
case 'utf8':
case 'utf-8':
return utf8Slice(this, start, end)
case 'ascii':
return asciiSlice(this, start, end)
case 'latin1':
case 'binary':
return latin1Slice(this, start, end)
case 'base64':
return base64Slice(this, start, end)
case 'ucs2':
case 'ucs-2':
case 'utf16le':
case 'utf-16le':
return utf16leSlice(this, start, end)
default:
if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
encoding = (encoding + '').toLowerCase();
loweredCase = true;
}
}
}
// This property is used by `Buffer.isBuffer` (and the `is-buffer` npm package)
// to detect a Buffer instance. It's not possible to use `instanceof Buffer`
// reliably in a browserify context because there could be multiple different
// copies of the 'buffer' package in use. This method works even for Buffer
// instances that were created from another copy of the `buffer` package.
// See: https://github.com/feross/buffer/issues/154
Buffer.prototype._isBuffer = true;
function swap (b, n, m) {
const i = b[n];
b[n] = b[m];
b[m] = i;
}
Buffer.prototype.swap16 = function swap16 () {
const len = this.length;
if (len % 2 !== 0) {
throw new RangeError('Buffer size must be a multiple of 16-bits')
}
for (let i = 0; i < len; i += 2) {
swap(this, i, i + 1);
}
return this
};
Buffer.prototype.swap32 = function swap32 () {
const len = this.length;
if (len % 4 !== 0) {
throw new RangeError('Buffer size must be a multiple of 32-bits')
}
for (let i = 0; i < len; i += 4) {
swap(this, i, i + 3);
swap(this, i + 1, i + 2);
}
return this
};
Buffer.prototype.swap64 = function swap64 () {
const len = this.length;
if (len % 8 !== 0) {
throw new RangeError('Buffer size must be a multiple of 64-bits')
}
for (let i = 0; i < len; i += 8) {
swap(this, i, i + 7);
swap(this, i + 1, i + 6);
swap(this, i + 2, i + 5);
swap(this, i + 3, i + 4);
}
return this
};
Buffer.prototype.toString = function toString () {
const length = this.length;
if (length === 0) return ''
if (arguments.length === 0) return utf8Slice(this, 0, length)
return slowToString.apply(this, arguments)
};
Buffer.prototype.toLocaleString = Buffer.prototype.toString;
Buffer.prototype.equals = function equals (b) {
if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
if (this === b) return true
return Buffer.compare(this, b) === 0
};
Buffer.prototype.inspect = function inspect () {
let str = '';
const max = exports.INSPECT_MAX_BYTES;
str = this.toString('hex', 0, max).replace(/(.{2})/g, '$1 ').trim();
if (this.length > max) str += ' ... ';
return '<Buffer ' + str + '>'
};
if (customInspectSymbol) {
Buffer.prototype[customInspectSymbol] = Buffer.prototype.inspect;
}
Buffer.prototype.compare = function compare (target, start, end, thisStart, thisEnd) {
if (isInstance(target, Uint8Array)) {
target = Buffer.from(target, target.offset, target.byteLength);
}
if (!Buffer.isBuffer(target)) {
throw new TypeError(
'The "target" argument must be one of type Buffer or Uint8Array. ' +
'Received type ' + (typeof target)
)
}
if (start === undefined) {
start = 0;
}
if (end === undefined) {
end = target ? target.length : 0;
}
if (thisStart === undefined) {
thisStart = 0;
}
if (thisEnd === undefined) {
thisEnd = this.length;
}
if (start < 0 || end > target.length || thisStart < 0 || thisEnd > this.length) {
throw new RangeError('out of range index')
}
if (thisStart >= thisEnd && start >= end) {
return 0
}
if (thisStart >= thisEnd) {
return -1
}
if (start >= end) {
return 1
}
start >>>= 0;
end >>>= 0;
thisStart >>>= 0;
thisEnd >>>= 0;
if (this === target) return 0
let x = thisEnd - thisStart;
let y = end - start;
const len = Math.min(x, y);
const thisCopy = this.slice(thisStart, thisEnd);
const targetCopy = target.slice(start, end);
for (let i = 0; i < len; ++i) {
if (thisCopy[i] !== targetCopy[i]) {
x = thisCopy[i];
y = targetCopy[i];
break
}
}
if (x < y) return -1
if (y < x) return 1
return 0
};
// Finds either the first index of `val` in `buffer` at offset >= `byteOffset`,
// OR the last index of `val` in `buffer` at offset <= `byteOffset`.
//
// Arguments:
// - buffer - a Buffer to search
// - val - a string, Buffer, or number
// - byteOffset - an index into `buffer`; will be clamped to an int32
// - encoding - an optional encoding, relevant is val is a string
// - dir - true for indexOf, false for lastIndexOf
function bidirectionalIndexOf (buffer, val, byteOffset, encoding, dir) {
// Empty buffer means no match
if (buffer.length === 0) return -1
// Normalize byteOffset
if (typeof byteOffset === 'string') {
encoding = byteOffset;
byteOffset = 0;
} else if (byteOffset > 0x7fffffff) {
byteOffset = 0x7fffffff;
} else if (byteOffset < -0x80000000) {
byteOffset = -0x80000000;
}
byteOffset = +byteOffset; // Coerce to Number.
if (numberIsNaN(byteOffset)) {
// byteOffset: it it's undefined, null, NaN, "foo", etc, search whole buffer
byteOffset = dir ? 0 : (buffer.length - 1);
}
// Normalize byteOffset: negative offsets start from the end of the buffer
if (byteOffset < 0) byteOffset = buffer.length + byteOffset;
if (byteOffset >= buffer.length) {
if (dir) return -1
else byteOffset = buffer.length - 1;
} else if (byteOffset < 0) {
if (dir) byteOffset = 0;
else return -1
}
// Normalize val
if (typeof val === 'string') {
val = Buffer.from(val, encoding);
}
// Finally, search either indexOf (if dir is true) or lastIndexOf
if (Buffer.isBuffer(val)) {
// Special case: looking for empty string/buffer always fails
if (val.length === 0) {
return -1
}
return arrayIndexOf(buffer, val, byteOffset, encoding, dir)
} else if (typeof val === 'number') {
val = val & 0xFF; // Search for a byte value [0-255]
if (typeof Uint8Array.prototype.indexOf === 'function') {
if (dir) {
return Uint8Array.prototype.indexOf.call(buffer, val, byteOffset)
} else {
return Uint8Array.prototype.lastIndexOf.call(buffer, val, byteOffset)
}
}
return arrayIndexOf(buffer, [val], byteOffset, encoding, dir)
}
throw new TypeError('val must be string, number or Buffer')
}
function arrayIndexOf (arr, val, byteOffset, encoding, dir) {
let indexSize = 1;
let arrLength = arr.length;
let valLength = val.length;
if (encoding !== undefined) {
encoding = String(encoding).toLowerCase();
if (encoding === 'ucs2' || encoding === 'ucs-2' ||
encoding === 'utf16le' || encoding === 'utf-16le') {
if (arr.length < 2 || val.length < 2) {
return -1
}
indexSize = 2;
arrLength /= 2;
valLength /= 2;
byteOffset /= 2;
}
}
function read (buf, i) {
if (indexSize === 1) {
return buf[i]
} else {
return buf.readUInt16BE(i * indexSize)
}
}
let i;
if (dir) {
let foundIndex = -1;
for (i = byteOffset; i < arrLength; i++) {
if (read(arr, i) === read(val, foundIndex === -1 ? 0 : i - foundIndex)) {
if (foundIndex === -1) foundIndex = i;
if (i - foundIndex + 1 === valLength) return foundIndex * indexSize
} else {
if (foundIndex !== -1) i -= i - foundIndex;
foundIndex = -1;
}
}
} else {
if (byteOffset + valLength > arrLength) byteOffset = arrLength - valLength;
for (i = byteOffset; i >= 0; i--) {
let found = true;
for (let j = 0; j < valLength; j++) {
if (read(arr, i + j) !== read(val, j)) {
found = false;
break
}
}
if (found) return i
}
}
return -1
}
Buffer.prototype.includes = function includes (val, byteOffset, encoding) {
return this.indexOf(val, byteOffset, encoding) !== -1
};
Buffer.prototype.indexOf = function indexOf (val, byteOffset, encoding) {
return bidirectionalIndexOf(this, val, byteOffset, encoding, true)
};
Buffer.prototype.lastIndexOf = function lastIndexOf (val, byteOffset, encoding) {
return bidirectionalIndexOf(this, val, byteOffset, encoding, false)
};
function hexWrite (buf, string, offset, length) {
offset = Number(offset) || 0;
const remaining = buf.length - offset;
if (!length) {
length = remaining;
} else {
length = Number(length);
if (length > remaining) {
length = remaining;
}
}
const strLen = string.length;
if (length > strLen / 2) {
length = strLen / 2;
}
let i;
for (i = 0; i < length; ++i) {
const parsed = parseInt(string.substr(i * 2, 2), 16);
if (numberIsNaN(parsed)) return i
buf[offset + i] = parsed;
}
return i
}
function utf8Write (buf, string, offset, length) {
return blitBuffer(utf8ToBytes(string, buf.length - offset), buf, offset, length)
}
function asciiWrite (buf, string, offset, length) {
return blitBuffer(asciiToBytes(string), buf, offset, length)
}
function base64Write (buf, string, offset, length) {
return blitBuffer(base64ToBytes(string), buf, offset, length)
}
function ucs2Write (buf, string, offset, length) {
return blitBuffer(utf16leToBytes(string, buf.length - offset), buf, offset, length)
}
Buffer.prototype.write = function write (string, offset, length, encoding) {
// Buffer#write(string)
if (offset === undefined) {
encoding = 'utf8';
length = this.length;
offset = 0;
// Buffer#write(string, encoding)
} else if (length === undefined && typeof offset === 'string') {
encoding = offset;
length = this.length;
offset = 0;
// Buffer#write(string, offset[, length][, encoding])
} else if (isFinite(offset)) {
offset = offset >>> 0;
if (isFinite(length)) {
length = length >>> 0;
if (encoding === undefined) encoding = 'utf8';
} else {
encoding = length;
length = undefined;
}
} else {
throw new Error(
'Buffer.write(string, encoding, offset[, length]) is no longer supported'
)
}
const remaining = this.length - offset;
if (length === undefined || length > remaining) length = remaining;
if ((string.length > 0 && (length < 0 || offset < 0)) || offset > this.length) {
throw new RangeError('Attempt to write outside buffer bounds')
}
if (!encoding) encoding = 'utf8';
let loweredCase = false;
for (;;) {
switch (encoding) {
case 'hex':
return hexWrite(this, string, offset, length)
case 'utf8':
case 'utf-8':
return utf8Write(this, string, offset, length)
case 'ascii':
case 'latin1':
case 'binary':
return asciiWrite(this, string, offset, length)
case 'base64':
// Warning: maxLength not taken into account in base64Write
return base64Write(this, string, offset, length)
case 'ucs2':
case 'ucs-2':
case 'utf16le':
case 'utf-16le':
return ucs2Write(this, string, offset, length)
default:
if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
encoding = ('' + encoding).toLowerCase();
loweredCase = true;
}
}
};
Buffer.prototype.toJSON = function toJSON () {
return {
type: 'Buffer',
data: Array.prototype.slice.call(this._arr || this, 0)
}
};
function base64Slice (buf, start, end) {
if (start === 0 && end === buf.length) {
return base64Js.fromByteArray(buf)
} else {
return base64Js.fromByteArray(buf.slice(start, end))
}
}
function utf8Slice (buf, start, end) {
end = Math.min(buf.length, end);
const res = [];
let i = start;
while (i < end) {
const firstByte = buf[i];
let codePoint = null;
let bytesPerSequence = (firstByte > 0xEF)
? 4
: (firstByte > 0xDF)
? 3
: (firstByte > 0xBF)
? 2
: 1;
if (i + bytesPerSequence <= end) {
let secondByte, thirdByte, fourthByte, tempCodePoint;
switch (bytesPerSequence) {
case 1:
if (firstByte < 0x80) {
codePoint = firstByte;
}
break
case 2:
secondByte = buf[i + 1];
if ((secondByte & 0xC0) === 0x80) {
tempCodePoint = (firstByte & 0x1F) << 0x6 | (secondByte & 0x3F);
if (tempCodePoint > 0x7F) {
codePoint = tempCodePoint;
}
}
break
case 3:
secondByte = buf[i + 1];
thirdByte = buf[i + 2];
if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80) {
tempCodePoint = (firstByte & 0xF) << 0xC | (secondByte & 0x3F) << 0x6 | (thirdByte & 0x3F);
if (tempCodePoint > 0x7FF && (tempCodePoint < 0xD800 || tempCodePoint > 0xDFFF)) {
codePoint = tempCodePoint;
}
}
break
case 4:
secondByte = buf[i + 1];
thirdByte = buf[i + 2];
fourthByte = buf[i + 3];
if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80 && (fourthByte & 0xC0) === 0x80) {
tempCodePoint = (firstByte & 0xF) << 0x12 | (secondByte & 0x3F) << 0xC | (thirdByte & 0x3F) << 0x6 | (fourthByte & 0x3F);
if (tempCodePoint > 0xFFFF && tempCodePoint < 0x110000) {
codePoint = tempCodePoint;
}
}
}
}
if (codePoint === null) {
// we did not generate a valid codePoint so insert a
// replacement char (U+FFFD) and advance only 1 byte
codePoint = 0xFFFD;
bytesPerSequence = 1;
} else if (codePoint > 0xFFFF) {
// encode to utf16 (surrogate pair dance)
codePoint -= 0x10000;
res.push(codePoint >>> 10 & 0x3FF | 0xD800);
codePoint = 0xDC00 | codePoint & 0x3FF;
}
res.push(codePoint);
i += bytesPerSequence;
}
return decodeCodePointsArray(res)
}
// Based on http://stackoverflow.com/a/22747272/680742, the browser with
// the lowest limit is Chrome, with 0x10000 args.
// We go 1 magnitude less, for safety
const MAX_ARGUMENTS_LENGTH = 0x1000;
function decodeCodePointsArray (codePoints) {
const len = codePoints.length;
if (len <= MAX_ARGUMENTS_LENGTH) {
return String.fromCharCode.apply(String, codePoints) // avoid extra slice()
}
// Decode in chunks to avoid "call stack size exceeded".
let res = '';
let i = 0;
while (i < len) {
res += String.fromCharCode.apply(
String,
codePoints.slice(i, i += MAX_ARGUMENTS_LENGTH)
);
}
return res
}
function asciiSlice (buf, start, end) {
let ret = '';
end = Math.min(buf.length, end);
for (let i = start; i < end; ++i) {
ret += String.fromCharCode(buf[i] & 0x7F);
}
return ret
}
function latin1Slice (buf, start, end) {
let ret = '';
end = Math.min(buf.length, end);
for (let i = start; i < end; ++i) {
ret += String.fromCharCode(buf[i]);
}
return ret
}
function hexSlice (buf, start, end) {
const len = buf.length;
if (!start || start < 0) start = 0;
if (!end || end < 0 || end > len) end = len;
let out = '';
for (let i = start; i < end; ++i) {
out += hexSliceLookupTable[buf[i]];
}
return out
}
function utf16leSlice (buf, start, end) {
const bytes = buf.slice(start, end);
let res = '';
// If bytes.length is odd, the last 8 bits must be ignored (same as node.js)
for (let i = 0; i < bytes.length - 1; i += 2) {
res += String.fromCharCode(bytes[i] + (bytes[i + 1] * 256));
}
return res
}
Buffer.prototype.slice = function slice (start, end) {
const len = this.length;
start = ~~start;
end = end === undefined ? len : ~~end;
if (start < 0) {
start += len;
if (start < 0) start = 0;
} else if (start > len) {
start = len;
}
if (end < 0) {
end += len;
if (end < 0) end = 0;
} else if (end > len) {
end = len;
}
if (end < start) end = start;
const newBuf = this.subarray(start, end);
// Return an augmented `Uint8Array` instance
Object.setPrototypeOf(newBuf, Buffer.prototype);
return newBuf
};
/*
* Need to make sure that buffer isn't trying to write out of bounds.
*/
function checkOffset (offset, ext, length) {
if ((offset % 1) !== 0 || offset < 0) throw new RangeError('offset is not uint')
if (offset + ext > length) throw new RangeError('Trying to access beyond buffer length')
}
Buffer.prototype.readUintLE =
Buffer.prototype.readUIntLE = function readUIntLE (offset, byteLength, noAssert) {
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) checkOffset(offset, byteLength, this.length);
let val = this[offset];
let mul = 1;
let i = 0;
while (++i < byteLength && (mul *= 0x100)) {
val += this[offset + i] * mul;
}
return val
};
Buffer.prototype.readUintBE =
Buffer.prototype.readUIntBE = function readUIntBE (offset, byteLength, noAssert) {
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) {
checkOffset(offset, byteLength, this.length);
}
let val = this[offset + --byteLength];
let mul = 1;
while (byteLength > 0 && (mul *= 0x100)) {
val += this[offset + --byteLength] * mul;
}
return val
};
Buffer.prototype.readUint8 =
Buffer.prototype.readUInt8 = function readUInt8 (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 1, this.length);
return this[offset]
};
Buffer.prototype.readUint16LE =
Buffer.prototype.readUInt16LE = function readUInt16LE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 2, this.length);
return this[offset] | (this[offset + 1] << 8)
};
Buffer.prototype.readUint16BE =
Buffer.prototype.readUInt16BE = function readUInt16BE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 2, this.length);
return (this[offset] << 8) | this[offset + 1]
};
Buffer.prototype.readUint32LE =
Buffer.prototype.readUInt32LE = function readUInt32LE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return ((this[offset]) |
(this[offset + 1] << 8) |
(this[offset + 2] << 16)) +
(this[offset + 3] * 0x1000000)
};
Buffer.prototype.readUint32BE =
Buffer.prototype.readUInt32BE = function readUInt32BE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return (this[offset] * 0x1000000) +
((this[offset + 1] << 16) |
(this[offset + 2] << 8) |
this[offset + 3])
};
Buffer.prototype.readBigUInt64LE = defineBigIntMethod(function readBigUInt64LE (offset) {
offset = offset >>> 0;
validateNumber(offset, 'offset');
const first = this[offset];
const last = this[offset + 7];
if (first === undefined || last === undefined) {
boundsError(offset, this.length - 8);
}
const lo = first +
this[++offset] * 2 ** 8 +
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 24;
const hi = this[++offset] +
this[++offset] * 2 ** 8 +
this[++offset] * 2 ** 16 +
last * 2 ** 24;
return BigInt(lo) + (BigInt(hi) << BigInt(32))
});
Buffer.prototype.readBigUInt64BE = defineBigIntMethod(function readBigUInt64BE (offset) {
offset = offset >>> 0;
validateNumber(offset, 'offset');
const first = this[offset];
const last = this[offset + 7];
if (first === undefined || last === undefined) {
boundsError(offset, this.length - 8);
}
const hi = first * 2 ** 24 +
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 8 +
this[++offset];
const lo = this[++offset] * 2 ** 24 +
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 8 +
last;
return (BigInt(hi) << BigInt(32)) + BigInt(lo)
});
Buffer.prototype.readIntLE = function readIntLE (offset, byteLength, noAssert) {
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) checkOffset(offset, byteLength, this.length);
let val = this[offset];
let mul = 1;
let i = 0;
while (++i < byteLength && (mul *= 0x100)) {
val += this[offset + i] * mul;
}
mul *= 0x80;
if (val >= mul) val -= Math.pow(2, 8 * byteLength);
return val
};
Buffer.prototype.readIntBE = function readIntBE (offset, byteLength, noAssert) {
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) checkOffset(offset, byteLength, this.length);
let i = byteLength;
let mul = 1;
let val = this[offset + --i];
while (i > 0 && (mul *= 0x100)) {
val += this[offset + --i] * mul;
}
mul *= 0x80;
if (val >= mul) val -= Math.pow(2, 8 * byteLength);
return val
};
Buffer.prototype.readInt8 = function readInt8 (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 1, this.length);
if (!(this[offset] & 0x80)) return (this[offset])
return ((0xff - this[offset] + 1) * -1)
};
Buffer.prototype.readInt16LE = function readInt16LE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 2, this.length);
const val = this[offset] | (this[offset + 1] << 8);
return (val & 0x8000) ? val | 0xFFFF0000 : val
};
Buffer.prototype.readInt16BE = function readInt16BE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 2, this.length);
const val = this[offset + 1] | (this[offset] << 8);
return (val & 0x8000) ? val | 0xFFFF0000 : val
};
Buffer.prototype.readInt32LE = function readInt32LE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return (this[offset]) |
(this[offset + 1] << 8) |
(this[offset + 2] << 16) |
(this[offset + 3] << 24)
};
Buffer.prototype.readInt32BE = function readInt32BE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return (this[offset] << 24) |
(this[offset + 1] << 16) |
(this[offset + 2] << 8) |
(this[offset + 3])
};
Buffer.prototype.readBigInt64LE = defineBigIntMethod(function readBigInt64LE (offset) {
offset = offset >>> 0;
validateNumber(offset, 'offset');
const first = this[offset];
const last = this[offset + 7];
if (first === undefined || last === undefined) {
boundsError(offset, this.length - 8);
}
const val = this[offset + 4] +
this[offset + 5] * 2 ** 8 +
this[offset + 6] * 2 ** 16 +
(last << 24); // Overflow
return (BigInt(val) << BigInt(32)) +
BigInt(first +
this[++offset] * 2 ** 8 +
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 24)
});
Buffer.prototype.readBigInt64BE = defineBigIntMethod(function readBigInt64BE (offset) {
offset = offset >>> 0;
validateNumber(offset, 'offset');
const first = this[offset];
const last = this[offset + 7];
if (first === undefined || last === undefined) {
boundsError(offset, this.length - 8);
}
const val = (first << 24) + // Overflow
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 8 +
this[++offset];
return (BigInt(val) << BigInt(32)) +
BigInt(this[++offset] * 2 ** 24 +
this[++offset] * 2 ** 16 +
this[++offset] * 2 ** 8 +
last)
});
Buffer.prototype.readFloatLE = function readFloatLE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return ieee754.read(this, offset, true, 23, 4)
};
Buffer.prototype.readFloatBE = function readFloatBE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 4, this.length);
return ieee754.read(this, offset, false, 23, 4)
};
Buffer.prototype.readDoubleLE = function readDoubleLE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 8, this.length);
return ieee754.read(this, offset, true, 52, 8)
};
Buffer.prototype.readDoubleBE = function readDoubleBE (offset, noAssert) {
offset = offset >>> 0;
if (!noAssert) checkOffset(offset, 8, this.length);
return ieee754.read(this, offset, false, 52, 8)
};
function checkInt (buf, value, offset, ext, max, min) {
if (!Buffer.isBuffer(buf)) throw new TypeError('"buffer" argument must be a Buffer instance')
if (value > max || value < min) throw new RangeError('"value" argument is out of bounds')
if (offset + ext > buf.length) throw new RangeError('Index out of range')
}
Buffer.prototype.writeUintLE =
Buffer.prototype.writeUIntLE = function writeUIntLE (value, offset, byteLength, noAssert) {
value = +value;
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) {
const maxBytes = Math.pow(2, 8 * byteLength) - 1;
checkInt(this, value, offset, byteLength, maxBytes, 0);
}
let mul = 1;
let i = 0;
this[offset] = value & 0xFF;
while (++i < byteLength && (mul *= 0x100)) {
this[offset + i] = (value / mul) & 0xFF;
}
return offset + byteLength
};
Buffer.prototype.writeUintBE =
Buffer.prototype.writeUIntBE = function writeUIntBE (value, offset, byteLength, noAssert) {
value = +value;
offset = offset >>> 0;
byteLength = byteLength >>> 0;
if (!noAssert) {
const maxBytes = Math.pow(2, 8 * byteLength) - 1;
checkInt(this, value, offset, byteLength, maxBytes, 0);
}
let i = byteLength - 1;
let mul = 1;
this[offset + i] = value & 0xFF;
while (--i >= 0 && (mul *= 0x100)) {
this[offset + i] = (value / mul) & 0xFF;
}
return offset + byteLength
};
Buffer.prototype.writeUint8 =
Buffer.prototype.writeUInt8 = function writeUInt8 (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 1, 0xff, 0);
this[offset] = (value & 0xff);
return offset + 1
};
Buffer.prototype.writeUint16LE =
Buffer.prototype.writeUInt16LE = function writeUInt16LE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0);
this[offset] = (value & 0xff);
this[offset + 1] = (value >>> 8);
return offset + 2
};
Buffer.prototype.writeUint16BE =
Buffer.prototype.writeUInt16BE = function writeUInt16BE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 2, 0xffff, 0);
this[offset] = (value >>> 8);
this[offset + 1] = (value & 0xff);
return offset + 2
};
Buffer.prototype.writeUint32LE =
Buffer.prototype.writeUInt32LE = function writeUInt32LE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0);
this[offset + 3] = (value >>> 24);
this[offset + 2] = (value >>> 16);
this[offset + 1] = (value >>> 8);
this[offset] = (value & 0xff);
return offset + 4
};
Buffer.prototype.writeUint32BE =
Buffer.prototype.writeUInt32BE = function writeUInt32BE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 4, 0xffffffff, 0);
this[offset] = (value >>> 24);
this[offset + 1] = (value >>> 16);
this[offset + 2] = (value >>> 8);
this[offset + 3] = (value & 0xff);
return offset + 4
};
function wrtBigUInt64LE (buf, value, offset, min, max) {
checkIntBI(value, min, max, buf, offset, 7);
let lo = Number(value & BigInt(0xffffffff));
buf[offset++] = lo;
lo = lo >> 8;
buf[offset++] = lo;
lo = lo >> 8;
buf[offset++] = lo;
lo = lo >> 8;
buf[offset++] = lo;
let hi = Number(value >> BigInt(32) & BigInt(0xffffffff));
buf[offset++] = hi;
hi = hi >> 8;
buf[offset++] = hi;
hi = hi >> 8;
buf[offset++] = hi;
hi = hi >> 8;
buf[offset++] = hi;
return offset
}
function wrtBigUInt64BE (buf, value, offset, min, max) {
checkIntBI(value, min, max, buf, offset, 7);
let lo = Number(value & BigInt(0xffffffff));
buf[offset + 7] = lo;
lo = lo >> 8;
buf[offset + 6] = lo;
lo = lo >> 8;
buf[offset + 5] = lo;
lo = lo >> 8;
buf[offset + 4] = lo;
let hi = Number(value >> BigInt(32) & BigInt(0xffffffff));
buf[offset + 3] = hi;
hi = hi >> 8;
buf[offset + 2] = hi;
hi = hi >> 8;
buf[offset + 1] = hi;
hi = hi >> 8;
buf[offset] = hi;
return offset + 8
}
Buffer.prototype.writeBigUInt64LE = defineBigIntMethod(function writeBigUInt64LE (value, offset = 0) {
return wrtBigUInt64LE(this, value, offset, BigInt(0), BigInt('0xffffffffffffffff'))
});
Buffer.prototype.writeBigUInt64BE = defineBigIntMethod(function writeBigUInt64BE (value, offset = 0) {
return wrtBigUInt64BE(this, value, offset, BigInt(0), BigInt('0xffffffffffffffff'))
});
Buffer.prototype.writeIntLE = function writeIntLE (value, offset, byteLength, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) {
const limit = Math.pow(2, (8 * byteLength) - 1);
checkInt(this, value, offset, byteLength, limit - 1, -limit);
}
let i = 0;
let mul = 1;
let sub = 0;
this[offset] = value & 0xFF;
while (++i < byteLength && (mul *= 0x100)) {
if (value < 0 && sub === 0 && this[offset + i - 1] !== 0) {
sub = 1;
}
this[offset + i] = ((value / mul) >> 0) - sub & 0xFF;
}
return offset + byteLength
};
Buffer.prototype.writeIntBE = function writeIntBE (value, offset, byteLength, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) {
const limit = Math.pow(2, (8 * byteLength) - 1);
checkInt(this, value, offset, byteLength, limit - 1, -limit);
}
let i = byteLength - 1;
let mul = 1;
let sub = 0;
this[offset + i] = value & 0xFF;
while (--i >= 0 && (mul *= 0x100)) {
if (value < 0 && sub === 0 && this[offset + i + 1] !== 0) {
sub = 1;
}
this[offset + i] = ((value / mul) >> 0) - sub & 0xFF;
}
return offset + byteLength
};
Buffer.prototype.writeInt8 = function writeInt8 (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 1, 0x7f, -0x80);
if (value < 0) value = 0xff + value + 1;
this[offset] = (value & 0xff);
return offset + 1
};
Buffer.prototype.writeInt16LE = function writeInt16LE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000);
this[offset] = (value & 0xff);
this[offset + 1] = (value >>> 8);
return offset + 2
};
Buffer.prototype.writeInt16BE = function writeInt16BE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 2, 0x7fff, -0x8000);
this[offset] = (value >>> 8);
this[offset + 1] = (value & 0xff);
return offset + 2
};
Buffer.prototype.writeInt32LE = function writeInt32LE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000);
this[offset] = (value & 0xff);
this[offset + 1] = (value >>> 8);
this[offset + 2] = (value >>> 16);
this[offset + 3] = (value >>> 24);
return offset + 4
};
Buffer.prototype.writeInt32BE = function writeInt32BE (value, offset, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) checkInt(this, value, offset, 4, 0x7fffffff, -0x80000000);
if (value < 0) value = 0xffffffff + value + 1;
this[offset] = (value >>> 24);
this[offset + 1] = (value >>> 16);
this[offset + 2] = (value >>> 8);
this[offset + 3] = (value & 0xff);
return offset + 4
};
Buffer.prototype.writeBigInt64LE = defineBigIntMethod(function writeBigInt64LE (value, offset = 0) {
return wrtBigUInt64LE(this, value, offset, -BigInt('0x8000000000000000'), BigInt('0x7fffffffffffffff'))
});
Buffer.prototype.writeBigInt64BE = defineBigIntMethod(function writeBigInt64BE (value, offset = 0) {
return wrtBigUInt64BE(this, value, offset, -BigInt('0x8000000000000000'), BigInt('0x7fffffffffffffff'))
});
function checkIEEE754 (buf, value, offset, ext, max, min) {
if (offset + ext > buf.length) throw new RangeError('Index out of range')
if (offset < 0) throw new RangeError('Index out of range')
}
function writeFloat (buf, value, offset, littleEndian, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) {
checkIEEE754(buf, value, offset, 4);
}
ieee754.write(buf, value, offset, littleEndian, 23, 4);
return offset + 4
}
Buffer.prototype.writeFloatLE = function writeFloatLE (value, offset, noAssert) {
return writeFloat(this, value, offset, true, noAssert)
};
Buffer.prototype.writeFloatBE = function writeFloatBE (value, offset, noAssert) {
return writeFloat(this, value, offset, false, noAssert)
};
function writeDouble (buf, value, offset, littleEndian, noAssert) {
value = +value;
offset = offset >>> 0;
if (!noAssert) {
checkIEEE754(buf, value, offset, 8);
}
ieee754.write(buf, value, offset, littleEndian, 52, 8);
return offset + 8
}
Buffer.prototype.writeDoubleLE = function writeDoubleLE (value, offset, noAssert) {
return writeDouble(this, value, offset, true, noAssert)
};
Buffer.prototype.writeDoubleBE = function writeDoubleBE (value, offset, noAssert) {
return writeDouble(this, value, offset, false, noAssert)
};
// copy(targetBuffer, targetStart=0, sourceStart=0, sourceEnd=buffer.length)
Buffer.prototype.copy = function copy (target, targetStart, start, end) {
if (!Buffer.isBuffer(target)) throw new TypeError('argument should be a Buffer')
if (!start) start = 0;
if (!end && end !== 0) end = this.length;
if (targetStart >= target.length) targetStart = target.length;
if (!targetStart) targetStart = 0;
if (end > 0 && end < start) end = start;
// Copy 0 bytes; we're done
if (end === start) return 0
if (target.length === 0 || this.length === 0) return 0
// Fatal error conditions
if (targetStart < 0) {
throw new RangeError('targetStart out of bounds')
}
if (start < 0 || start >= this.length) throw new RangeError('Index out of range')
if (end < 0) throw new RangeError('sourceEnd out of bounds')
// Are we oob?
if (end > this.length) end = this.length;
if (target.length - targetStart < end - start) {
end = target.length - targetStart + start;
}
const len = end - start;
if (this === target && typeof Uint8Array.prototype.copyWithin === 'function') {
// Use built-in when available, missing from IE11
this.copyWithin(targetStart, start, end);
} else {
Uint8Array.prototype.set.call(
target,
this.subarray(start, end),
targetStart
);
}
return len
};
// Usage:
// buffer.fill(number[, offset[, end]])
// buffer.fill(buffer[, offset[, end]])
// buffer.fill(string[, offset[, end]][, encoding])
Buffer.prototype.fill = function fill (val, start, end, encoding) {
// Handle string cases:
if (typeof val === 'string') {
if (typeof start === 'string') {
encoding = start;
start = 0;
end = this.length;
} else if (typeof end === 'string') {
encoding = end;
end = this.length;
}
if (encoding !== undefined && typeof encoding !== 'string') {
throw new TypeError('encoding must be a string')
}
if (typeof encoding === 'string' && !Buffer.isEncoding(encoding)) {
throw new TypeError('Unknown encoding: ' + encoding)
}
if (val.length === 1) {
const code = val.charCodeAt(0);
if ((encoding === 'utf8' && code < 128) ||
encoding === 'latin1') {
// Fast path: If `val` fits into a single byte, use that numeric value.
val = code;
}
}
} else if (typeof val === 'number') {
val = val & 255;
} else if (typeof val === 'boolean') {
val = Number(val);
}
// Invalid ranges are not set to a default, so can range check early.
if (start < 0 || this.length < start || this.length < end) {
throw new RangeError('Out of range index')
}
if (end <= start) {
return this
}
start = start >>> 0;
end = end === undefined ? this.length : end >>> 0;
if (!val) val = 0;
let i;
if (typeof val === 'number') {
for (i = start; i < end; ++i) {
this[i] = val;
}
} else {
const bytes = Buffer.isBuffer(val)
? val
: Buffer.from(val, encoding);
const len = bytes.length;
if (len === 0) {
throw new TypeError('The value "' + val +
'" is invalid for argument "value"')
}
for (i = 0; i < end - start; ++i) {
this[i + start] = bytes[i % len];
}
}
return this
};
// CUSTOM ERRORS
// =============
// Simplified versions from Node, changed for Buffer-only usage
const errors = {};
function E (sym, getMessage, Base) {
errors[sym] = class NodeError extends Base {
constructor () {
super();
Object.defineProperty(this, 'message', {
value: getMessage.apply(this, arguments),
writable: true,
configurable: true
});
// Add the error code to the name to include it in the stack trace.
this.name = `${this.name} [${sym}]`;
// Access the stack to generate the error message including the error code
// from the name.
this.stack; // eslint-disable-line no-unused-expressions
// Reset the name to the actual name.
delete this.name;
}
get code () {
return sym
}
set code (value) {
Object.defineProperty(this, 'code', {
configurable: true,
enumerable: true,
value,
writable: true
});
}
toString () {
return `${this.name} [${sym}]: ${this.message}`
}
};
}
E('ERR_BUFFER_OUT_OF_BOUNDS',
function (name) {
if (name) {
return `${name} is outside of buffer bounds`
}
return 'Attempt to access memory outside buffer bounds'
}, RangeError);
E('ERR_INVALID_ARG_TYPE',
function (name, actual) {
return `The "${name}" argument must be of type number. Received type ${typeof actual}`
}, TypeError);
E('ERR_OUT_OF_RANGE',
function (str, range, input) {
let msg = `The value of "${str}" is out of range.`;
let received = input;
if (Number.isInteger(input) && Math.abs(input) > 2 ** 32) {
received = addNumericalSeparator(String(input));
} else if (typeof input === 'bigint') {
received = String(input);
if (input > BigInt(2) ** BigInt(32) || input < -(BigInt(2) ** BigInt(32))) {
received = addNumericalSeparator(received);
}
received += 'n';
}
msg += ` It must be ${range}. Received ${received}`;
return msg
}, RangeError);
function addNumericalSeparator (val) {
let res = '';
let i = val.length;
const start = val[0] === '-' ? 1 : 0;
for (; i >= start + 4; i -= 3) {
res = `_${val.slice(i - 3, i)}${res}`;
}
return `${val.slice(0, i)}${res}`
}
// CHECK FUNCTIONS
// ===============
function checkBounds (buf, offset, byteLength) {
validateNumber(offset, 'offset');
if (buf[offset] === undefined || buf[offset + byteLength] === undefined) {
boundsError(offset, buf.length - (byteLength + 1));
}
}
function checkIntBI (value, min, max, buf, offset, byteLength) {
if (value > max || value < min) {
const n = typeof min === 'bigint' ? 'n' : '';
let range;
if (byteLength > 3) {
if (min === 0 || min === BigInt(0)) {
range = `>= 0${n} and < 2${n} ** ${(byteLength + 1) * 8}${n}`;
} else {
range = `>= -(2${n} ** ${(byteLength + 1) * 8 - 1}${n}) and < 2 ** ` +
`${(byteLength + 1) * 8 - 1}${n}`;
}
} else {
range = `>= ${min}${n} and <= ${max}${n}`;
}
throw new errors.ERR_OUT_OF_RANGE('value', range, value)
}
checkBounds(buf, offset, byteLength);
}
function validateNumber (value, name) {
if (typeof value !== 'number') {
throw new errors.ERR_INVALID_ARG_TYPE(name, 'number', value)
}
}
function boundsError (value, length, type) {
if (Math.floor(value) !== value) {
validateNumber(value, type);
throw new errors.ERR_OUT_OF_RANGE(type || 'offset', 'an integer', value)
}
if (length < 0) {
throw new errors.ERR_BUFFER_OUT_OF_BOUNDS()
}
throw new errors.ERR_OUT_OF_RANGE(type || 'offset',
`>= ${type ? 1 : 0} and <= ${length}`,
value)
}
// HELPER FUNCTIONS
// ================
const INVALID_BASE64_RE = /[^+/0-9A-Za-z-_]/g;
function base64clean (str) {
// Node takes equal signs as end of the Base64 encoding
str = str.split('=')[0];
// Node strips out invalid characters like \n and \t from the string, base64-js does not
str = str.trim().replace(INVALID_BASE64_RE, '');
// Node converts strings with length < 2 to ''
if (str.length < 2) return ''
// Node allows for non-padded base64 strings (missing trailing ===), base64-js does not
while (str.length % 4 !== 0) {
str = str + '=';
}
return str
}
function utf8ToBytes (string, units) {
units = units || Infinity;
let codePoint;
const length = string.length;
let leadSurrogate = null;
const bytes = [];
for (let i = 0; i < length; ++i) {
codePoint = string.charCodeAt(i);
// is surrogate component
if (codePoint > 0xD7FF && codePoint < 0xE000) {
// last char was a lead
if (!leadSurrogate) {
// no lead yet
if (codePoint > 0xDBFF) {
// unexpected trail
if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD);
continue
} else if (i + 1 === length) {
// unpaired lead
if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD);
continue
}
// valid lead
leadSurrogate = codePoint;
continue
}
// 2 leads in a row
if (codePoint < 0xDC00) {
if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD);
leadSurrogate = codePoint;
continue
}
// valid surrogate pair
codePoint = (leadSurrogate - 0xD800 << 10 | codePoint - 0xDC00) + 0x10000;
} else if (leadSurrogate) {
// valid bmp char, but last char was a lead
if ((units -= 3) > -1) bytes.push(0xEF, 0xBF, 0xBD);
}
leadSurrogate = null;
// encode utf8
if (codePoint < 0x80) {
if ((units -= 1) < 0) break
bytes.push(codePoint);
} else if (codePoint < 0x800) {
if ((units -= 2) < 0) break
bytes.push(
codePoint >> 0x6 | 0xC0,
codePoint & 0x3F | 0x80
);
} else if (codePoint < 0x10000) {
if ((units -= 3) < 0) break
bytes.push(
codePoint >> 0xC | 0xE0,
codePoint >> 0x6 & 0x3F | 0x80,
codePoint & 0x3F | 0x80
);
} else if (codePoint < 0x110000) {
if ((units -= 4) < 0) break
bytes.push(
codePoint >> 0x12 | 0xF0,
codePoint >> 0xC & 0x3F | 0x80,
codePoint >> 0x6 & 0x3F | 0x80,
codePoint & 0x3F | 0x80
);
} else {
throw new Error('Invalid code point')
}
}
return bytes
}
function asciiToBytes (str) {
const byteArray = [];
for (let i = 0; i < str.length; ++i) {
// Node's code seems to be doing this and not & 0x7F..
byteArray.push(str.charCodeAt(i) & 0xFF);
}
return byteArray
}
function utf16leToBytes (str, units) {
let c, hi, lo;
const byteArray = [];
for (let i = 0; i < str.length; ++i) {
if ((units -= 2) < 0) break
c = str.charCodeAt(i);
hi = c >> 8;
lo = c % 256;
byteArray.push(lo);
byteArray.push(hi);
}
return byteArray
}
function base64ToBytes (str) {
return base64Js.toByteArray(base64clean(str))
}
function blitBuffer (src, dst, offset, length) {
let i;
for (i = 0; i < length; ++i) {
if ((i + offset >= dst.length) || (i >= src.length)) break
dst[i + offset] = src[i];
}
return i
}
// ArrayBuffer or Uint8Array objects from other contexts (i.e. iframes) do not pass
// the `instanceof` check but they should be treated as of that type.
// See: https://github.com/feross/buffer/issues/166
function isInstance (obj, type) {
return obj instanceof type ||
(obj != null && obj.constructor != null && obj.constructor.name != null &&
obj.constructor.name === type.name)
}
function numberIsNaN (obj) {
// For IE11 support
return obj !== obj // eslint-disable-line no-self-compare
}
// Create lookup table for `toString('hex')`
// See: https://github.com/feross/buffer/issues/219
const hexSliceLookupTable = (function () {
const alphabet = '0123456789abcdef';
const table = new Array(256);
for (let i = 0; i < 16; ++i) {
const i16 = i * 16;
for (let j = 0; j < 16; ++j) {
table[i16 + j] = alphabet[i] + alphabet[j];
}
}
return table
})();
// Return not function with Error if BigInt not supported
function defineBigIntMethod (fn) {
return typeof BigInt === 'undefined' ? BufferBigIntNotDefined : fn
}
function BufferBigIntNotDefined () {
throw new Error('BigInt not supported')
}
});
class Shp {
constructor (options) {
this._options = options;
this._shpBuffer = null;
this._dbfBuffer = null;
this._projString = null;
this.loaded = false;
this._properties = null;
this._geomParser = null;
this._hasZ = false;
if (this._options.arraybuffers) {
this._shpBuffer = buffer.Buffer.from(this._options.arraybuffers.shpBuffer);
this._tableBuffer = this._options.arraybuffers.dbfBuffer ? buffer.Buffer.from(this._options.arraybuffers.dbfBuffer) : null;
this._projString = this._options.arraybuffers.projString ? buffer.Buffer.from(this._options.arraybuffers.projString) : null;
this._init();
}
}
load () {
const that = this;
return new Promise((resolveLoad, rejectLoad) => {
if (that._options.remotePath) {
const shpPromise = this._loadFilePromise(that._options.remotePath);
const dbfPromise = this._loadFilePromise(that._options.remotePath.replace('.shp', '.dbf'));
const projPromise = this._loadFilePromise(that._options.remotePath.replace('.shp', '.prj'), 'text');
// const qixPromise = this._loadFilePromise(that._options.remotePath.replace('.shp', '.qix'))
Promise.all([shpPromise, dbfPromise, projPromise])
.then((values) => {
that._shpBuffer = buffer.Buffer.from(values[0]);
that._tableBuffer = buffer.Buffer.from(values[1]);
that._projString = values[2];
that._init();
that.loaded = true;
resolveLoad();
})
.catch(error => {
rejectLoad(error);
});
} else {
resolveLoad();
}
})
}
_loadFilePromise (filepath, responseType) {
return new Promise((resolve, reject) => {
fetch(filepath)
.then(response => {
if (response.ok) {
if (responseType === 'text') return response.text()
return response.arrayBuffer()
} else {
throw new Error(`Could not resolve ${filepath}`)
}
})
.then(data => {
resolve(data);
})
.catch((err) => {
reject(err);
});
})
}
_init () {
this._properties = new Properties(this._tableBuffer);
this._geomParser = this._setGeometryParser();
this.loaded = true;
}
get _shpGeometryType () {
const geometryType = this._shpBuffer.readInt8(32);
let out = null;
switch (geometryType) {
case 1:
out = 'Point';
break;
case 11:
out = 'PointZ';
break;
case 21:
out = 'PointM';
break;
case 3:
out = 'PolyLine';
break;
case 13:
out = 'PolyLineZ';
break;
case 23:
out = 'PolyLineM';
break;
case 5:
out = 'Polygon';
break;
case 15:
out = 'PolygonZ';
break;
case 25:
out = 'PolygonM';
break;
case 8:
out = 'MultiPoint';
break;
case 18:
out = 'MultiPointZ';
break;
case 28:
out = 'MultiPointM';
break;
}
return out
}
get _bbox () {
return [
this._shpBuffer.readDoubleLE(36),
this._shpBuffer.readDoubleLE(44),
this._shpBuffer.readDoubleLE(52),
this._shpBuffer.readDoubleLE(60)
]
}
get _numberOfFeatures () {
return this._tableBuffer.readInt32LE(4)
}
get summary () {
return {
shpGeometryType: this._shpGeometryType,
numberOfFeatures: this._numberOfFeatures,
bbox: this._bbox,
crs: this._projString
}
}
_setGeometryParser () {
const geometryType = this._shpBuffer.readInt8(32);
if (geometryType === 11 || geometryType === 13 || geometryType === 15 || geometryType === 18) this._hasZ = true;
if (geometryType === 1 || geometryType === 11 || geometryType === 21) return createPoint
if (geometryType === 3 || geometryType === 13 || geometryType === 23) return createPolyline
if (geometryType === 5 || geometryType === 15 ||geometryType === 25) return createPolygon
if (geometryType === 8 || geometryType === 18 || geometryType === 88) return createMultiPoint
}
getGeoJson () {
const out = {
"type": "FeatureCollection",
"bbox": this._bbox,
"features": []
};
let start = 100;
let index = 0;
const bufferLength = this._shpBuffer.length;
while (start < bufferLength) {
const headerLength = start + 8;
const recordLength = this._shpBuffer.readInt32BE(start + 4) << 1;
out.features.push({
type: 'Feature',
properties: this._properties.getRowProperties(index),
geometry: this._geomParser(this._shpBuffer.slice(headerLength, headerLength + recordLength), this._hasZ)
});
start = headerLength + recordLength;
index++;
}
return out
}
* streamGeoJsonFeatures () {
let start = 100;
let index = 0;
while (start < this._shpBuffer.length) {
const headerLength = start + 8;
const header = this._shpBuffer.slice(start, headerLength);
const recordLength = header.readInt32BE(4) << 1;
yield {
type: 'Feature',
properties: this._properties.getRowProperties(index),
geometry: this._geomParser(this._shpBuffer.slice(headerLength, headerLength + recordLength))
};
index++;
start = headerLength + recordLength;
}
}
}
export default class BrowserShp extends Shp {
constructor (options) {
super(options);
if (options.filePath) {
throw new Error('filePath is not a valid option in the browser. Either use remotePath or the arraybuffer options')
} else if (options.filePathZipped) {
throw new Error('filePathZipped is not a valid option in the browser. Either use remotePath or the arraybuffer options')
}
}
}
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