@dstanesc/wasm-chunking-fastcdc-node/chunking.js

This crate generates WebAssembly bindings to the FastCDC content defined slicing library

let imports = {};
imports['__wbindgen_placeholder__'] = module.exports;
let wasm;
const { TextDecoder } = require(`util`);

let cachedTextDecoder = new TextDecoder('utf-8', { ignoreBOM: true, fatal: true });

cachedTextDecoder.decode();

let cachedUint8Memory0 = new Uint8Array();

function getUint8Memory0() {
    if (cachedUint8Memory0.byteLength === 0) {
        cachedUint8Memory0 = new Uint8Array(wasm.memory.buffer);
    }
    return cachedUint8Memory0;
}

function getStringFromWasm0(ptr, len) {
    return cachedTextDecoder.decode(getUint8Memory0().subarray(ptr, ptr + len));
}

let WASM_VECTOR_LEN = 0;

function passArray8ToWasm0(arg, malloc) {
    const ptr = malloc(arg.length * 1);
    getUint8Memory0().set(arg, ptr / 1);
    WASM_VECTOR_LEN = arg.length;
    return ptr;
}

let cachedInt32Memory0 = new Int32Array();

function getInt32Memory0() {
    if (cachedInt32Memory0.byteLength === 0) {
        cachedInt32Memory0 = new Int32Array(wasm.memory.buffer);
    }
    return cachedInt32Memory0;
}

const heap = new Array(32).fill(undefined);

heap.push(undefined, null, true, false);

function getObject(idx) { return heap[idx]; }

let heap_next = heap.length;

function dropObject(idx) {
    if (idx < 36) return;
    heap[idx] = heap_next;
    heap_next = idx;
}

function takeObject(idx) {
    const ret = getObject(idx);
    dropObject(idx);
    return ret;
}

let cachedUint32Memory0 = new Uint32Array();

function getUint32Memory0() {
    if (cachedUint32Memory0.byteLength === 0) {
        cachedUint32Memory0 = new Uint32Array(wasm.memory.buffer);
    }
    return cachedUint32Memory0;
}

function getArrayU32FromWasm0(ptr, len) {
    return getUint32Memory0().subarray(ptr / 4, ptr / 4 + len);
}
/**
*
* Compute chunks from a given slice of bytes.
*
* The `min_size` specifies the preferred minimum chunk size,
* `max_size` the preferred maximum chunk size; the `avg_size` is the
* desired "normal size" of the chunks. The smallest acceptable
* `min_size` is 64 bytes and likewise 256 bytes and 1024 bytes
* for `avg_size` and respectively `max_size`
*
* A js_sys::RangeError is returned when the above chunking specification is out of range.
*
*
* Example:
*
* ```
* use wasm_chunking_fastcdc::compute_chunks;
* let data: Vec<u8> = br"Lorem ipsum dolor sit amet, consectetur adipiscing elit...put more bits in here...".to_vec();
* let slice: &[u8] = &data;
* let min_size: u32 = 64;
* let avg_size: u32 = 256;
* let max_size: u32 = 1024;
* let offsets: Vec<u32> = compute_chunks(slice, min_size, avg_size, max_size).unwrap();
* ```
* @param {Uint8Array} source
* @param {number} min_size
* @param {number} avg_size
* @param {number} max_size
* @returns {Uint32Array}
*/
module.exports.compute_chunks = function(source, min_size, avg_size, max_size) {
    try {
        const retptr = wasm.__wbindgen_add_to_stack_pointer(-16);
        const ptr0 = passArray8ToWasm0(source, wasm.__wbindgen_malloc);
        const len0 = WASM_VECTOR_LEN;
        wasm.compute_chunks(retptr, ptr0, len0, min_size, avg_size, max_size);
        var r0 = getInt32Memory0()[retptr / 4 + 0];
        var r1 = getInt32Memory0()[retptr / 4 + 1];
        var r2 = getInt32Memory0()[retptr / 4 + 2];
        var r3 = getInt32Memory0()[retptr / 4 + 3];
        if (r3) {
            throw takeObject(r2);
        }
        var v1 = getArrayU32FromWasm0(r0, r1).slice();
        wasm.__wbindgen_free(r0, r1 * 4);
        return v1;
    } finally {
        wasm.__wbindgen_add_to_stack_pointer(16);
    }
};

/**
*
* Compute chunks from a given slice of bytes.
*
* The `min_size` specifies the preferred minimum chunk size,
* `max_size` the preferred maximum chunk size; the `avg_size` is the
* desired "normal size" of the chunks. The smallest acceptable
* `min_size` is 64 bytes and likewise 256 bytes and 1024 bytes
* for `avg_size` and respectively `max_size`
*
* No js friendly chunking specification range validation
* Example:
*
* ```
* use wasm_chunking_fastcdc::compute_chunks_nocheck;
* let data: Vec<u8> = br"Lorem ipsum dolor sit amet, consectetur adipiscing elit...put more bits in here...".to_vec();
* let slice: &[u8] = &data;
* let min_size: u32 = 64;
* let avg_size: u32 = 256;
* let max_size: u32 = 1024;
* let offsets: Vec<u32> = compute_chunks_nocheck(slice, min_size, avg_size, max_size);
* ```
* @param {Uint8Array} source
* @param {number} min_size
* @param {number} avg_size
* @param {number} max_size
* @returns {Uint32Array}
*/
module.exports.compute_chunks_nocheck = function(source, min_size, avg_size, max_size) {
    try {
        const retptr = wasm.__wbindgen_add_to_stack_pointer(-16);
        const ptr0 = passArray8ToWasm0(source, wasm.__wbindgen_malloc);
        const len0 = WASM_VECTOR_LEN;
        wasm.compute_chunks_nocheck(retptr, ptr0, len0, min_size, avg_size, max_size);
        var r0 = getInt32Memory0()[retptr / 4 + 0];
        var r1 = getInt32Memory0()[retptr / 4 + 1];
        var v1 = getArrayU32FromWasm0(r0, r1).slice();
        wasm.__wbindgen_free(r0, r1 * 4);
        return v1;
    } finally {
        wasm.__wbindgen_add_to_stack_pointer(16);
    }
};

function addHeapObject(obj) {
    if (heap_next === heap.length) heap.push(heap.length + 1);
    const idx = heap_next;
    heap_next = heap[idx];

    heap[idx] = obj;
    return idx;
}

module.exports.__wbg_new_bec064441604955e = function(arg0, arg1) {
    const ret = new RangeError(getStringFromWasm0(arg0, arg1));
    return addHeapObject(ret);
};

module.exports.__wbindgen_throw = function(arg0, arg1) {
    throw new Error(getStringFromWasm0(arg0, arg1));
};

const path = require('path').join(__dirname, 'chunking_bg.wasm');
const bytes = require('fs').readFileSync(path);

const wasmModule = new WebAssembly.Module(bytes);
const wasmInstance = new WebAssembly.Instance(wasmModule, imports);
wasm = wasmInstance.exports;
module.exports.__wasm = wasm;