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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
self.onmessage = async event => {
const fixed = await mac2unix(event.data.path, percent => {
self.postMessage({ msg: "progress", percent });
});
self.postMessage({ msg: "success", percent: 100, fixed });
self.close();
};
/**
* Convert bare CR line (classic MacOS) line endings to LF line endings,
* for the provided input file. If the data doesn't contain bare CR lines, the
* input data will remain untouched.
*
* @param {string} inputPath - Path to the mbox file to convert.
* @param {?function(number):void} onProgress - Called with progress percentage.
* @returns {boolean} whether repair was needed or not.
*/
async function mac2unix(inputPath, onProgress) {
const CHUNK_SIZE = 1024 * 1024; // 1 MiB.
const totalSize = (await IOUtils.stat(inputPath)).size;
let offset = 0;
const outputPath = await IOUtils.createUniqueFile(
PathUtils.parent(inputPath),
PathUtils.filename(inputPath) + ".tmp"
);
const CR = 0x0d;
const LF = 0x0a;
let changed = false;
// eslint-disable-next-line no-constant-condition
while (true) {
const chunk = await IOUtils.read(inputPath, {
offset,
maxBytes: CHUNK_SIZE,
});
if (!chunk.byteLength) {
break; // End of file
}
offset += chunk.byteLength;
// Modify data in-place (convert CR to LF, but preserve CRLF).
for (let i = 0; i < chunk.length; i++) {
if (chunk[i] === CR) {
if (i + 1 >= chunk.length) {
// CR was the last byte in chunk.
const nextByte = await IOUtils.read(inputPath, {
offset,
maxBytes: 1,
});
if (nextByte.byteLength === 0 || nextByte[0] !== LF) {
chunk[i] = LF; // CR not followed by LF; convert CR -> LF!
changed = true;
}
} else if (chunk[i + 1] !== LF) {
chunk[i] = LF; // CR not followed by LF; convert CR -> LF!
changed = true;
}
}
}
await IOUtils.write(outputPath, chunk, { mode: "append" });
onProgress?.((offset / totalSize) * 100);
}
if (changed) {
await IOUtils.move(outputPath, inputPath);
} else {
// Line endings repair not needed. Just remove the temp file.
await IOUtils.remove(outputPath);
}
return offset;
}