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'use strict';
// Map of id => function that releases a lock.
const held = new Map();
let next_lock_id = 1;
function processMessage(e) {
const target = this;
function respond(data) {
target.postMessage(Object.assign(data, {rqid: e.data.rqid}));
}
switch (e.data.op) {
case 'request': {
const controller = new AbortController();
navigator.locks.request(
e.data.name, {
mode: e.data.mode || 'exclusive',
ifAvailable: e.data.ifAvailable || false,
signal: e.data.abortImmediately ? controller.signal : undefined,
}, lock => {
if (lock === null) {
respond({ack: 'request', failed: true});
return;
}
let lock_id = next_lock_id++;
let release;
const promise = new Promise(r => { release = r; });
held.set(lock_id, release);
respond({ack: 'request', lock_id: lock_id});
return promise;
}).catch(e => {
respond({ack: 'request', error: e.name});
});
if (e.data.abortImmediately) {
controller.abort();
}
break;
}
case 'release':
held.get(e.data.lock_id)();
held.delete(e.data.lock_id);
respond({ack: 'release', lock_id: e.data.lock_id});
break;
}
}
self.addEventListener('message', processMessage);
self.addEventListener('connect', ev => {
// Shared worker case
ev.ports[0].onmessage = processMessage;
});