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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
/* eslint camelcase: 0*/
"use strict";
const {
getDwarfToWasmData,
} = require("resource://devtools/client/shared/source-map-loader/wasm-dwarf/wasmAsset.js");
let cachedWasmModule;
let utf8Decoder;
function convertDwarf(wasm, instance) {
const { memory, alloc_mem, free_mem, convert_dwarf } = instance.exports;
const wasmPtr = alloc_mem(wasm.byteLength);
new Uint8Array(memory.buffer, wasmPtr, wasm.byteLength).set(
new Uint8Array(wasm)
);
const resultPtr = alloc_mem(12);
const enableXScopes = true;
const success = convert_dwarf(
wasmPtr,
wasm.byteLength,
resultPtr,
resultPtr + 4,
enableXScopes
);
free_mem(wasmPtr);
const resultView = new DataView(memory.buffer, resultPtr, 12);
const outputPtr = resultView.getUint32(0, true),
outputLen = resultView.getUint32(4, true);
free_mem(resultPtr);
if (!success) {
throw new Error("Unable to convert from DWARF sections");
}
if (!utf8Decoder) {
utf8Decoder = new TextDecoder("utf-8");
}
const output = utf8Decoder.decode(
new Uint8Array(memory.buffer, outputPtr, outputLen)
);
free_mem(outputPtr);
return output;
}
async function convertToJSON(buffer) {
// Note: We don't 'await' here because it could mean that multiple
// calls to 'convertToJSON' could cause multiple fetches to be started.
cachedWasmModule = cachedWasmModule || loadConverterModule();
return convertDwarf(buffer, await cachedWasmModule);
}
async function loadConverterModule() {
const wasm = await getDwarfToWasmData();
const imports = {};
const { instance } = await WebAssembly.instantiate(wasm, imports);
return instance;
}
module.exports = {
convertToJSON,
};
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