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'use strict';
const smalloc = process.binding('smalloc');
const kMaxLength = smalloc.kMaxLength;
const util = require('util');
exports.alloc = alloc;
exports.copyOnto = smalloc.copyOnto;
exports.dispose = dispose;
exports.hasExternalData = smalloc.hasExternalData;
// don't allow kMaxLength to accidentally be overwritten. it's a lot less
// apparent when a primitive is accidentally changed.
Object.defineProperty(exports, 'kMaxLength', {
enumerable: true, value: kMaxLength, writable: false
});
// enumerated values for different external array types
var Types = {};
// Must match enum v8::ExternalArrayType.
Object.defineProperties(Types, {
'Int8': { enumerable: true, value: 1, writable: false },
'Uint8': { enumerable: true, value: 2, writable: false },
'Int16': { enumerable: true, value: 3, writable: false },
'Uint16': { enumerable: true, value: 4, writable: false },
'Int32': { enumerable: true, value: 5, writable: false },
'Uint32': { enumerable: true, value: 6, writable: false },
'Float': { enumerable: true, value: 7, writable: false },
'Double': { enumerable: true, value: 8, writable: false },
'Uint8Clamped': { enumerable: true, value: 9, writable: false }
});
Object.defineProperty(exports, 'Types', {
enumerable: true, value: Types, writable: false
});
// usage: obj = alloc(n[, obj][, type]);
function alloc(n, obj, type) {
n = n >>> 0;
if (obj === undefined)
obj = {};
if (typeof obj === 'number') {
type = obj >>> 0;
obj = {};
} else if (util.isPrimitive(obj)) {
throw new TypeError('obj must be an Object');
}
// 1 == v8::kExternalUint8Array, 9 == v8::kExternalUint8ClampedArray
if (type < 1 || type > 9)
throw new TypeError('unknown external array type: ' + type);
if (Array.isArray(obj))
throw new TypeError('Arrays are not supported');
if (n > kMaxLength)
throw new RangeError('n > kMaxLength');
return smalloc.alloc(obj, n, type);
}
function dispose(obj) {
if (util.isPrimitive(obj))
throw new TypeError('obj must be an Object');
if (obj instanceof Buffer)
throw new TypeError('obj cannot be a Buffer');
if (smalloc.isTypedArray(obj))
throw new TypeError('obj cannot be a typed array');
if (!smalloc.hasExternalData(obj))
throw new Error('obj has no external array data');
smalloc.dispose(obj);
}