index.js
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"use strict";
module.exports = pool;
/**
* An allocator as used by {@link util.pool}.
* @typedef PoolAllocator
* @type {function}
* @param {number} size Buffer size
* @returns {Uint8Array} Buffer
*/
/**
* A slicer as used by {@link util.pool}.
* @typedef PoolSlicer
* @type {function}
* @param {number} start Start offset
* @param {number} end End offset
* @returns {Uint8Array} Buffer slice
* @this {Uint8Array}
*/
/**
* A general purpose buffer pool.
* @memberof util
* @function
* @param {PoolAllocator} alloc Allocator
* @param {PoolSlicer} slice Slicer
* @param {number} [size=8192] Slab size
* @returns {PoolAllocator} Pooled allocator
*/
function pool(alloc, slice, size) {
var SIZE = size || 8192;
var MAX = SIZE >>> 1;
var slab = null;
var offset = SIZE;
return function pool_alloc(size) {
if (size < 1 || size > MAX)
return alloc(size);
if (offset + size > SIZE) {
slab = alloc(SIZE);
offset = 0;
}
var buf = slice.call(slab, offset, offset += size);
if (offset & 7) // align to 32 bit
offset = (offset | 7) + 1;
return buf;
};
}