// Note: since nyc uses this module to output coverage, any lines // that are in the direct sync flow of nyc's outputCoverage are // ignored, since we can never get coverage for them. var assert = require('assert') var signals = require('./signals.js') var EE = require('events') /* istanbul ignore if */ if (typeof EE !== 'function') { EE = EE.EventEmitter } var emitter if (process.__signal_exit_emitter__) { emitter = process.__signal_exit_emitter__ } else { emitter = process.__signal_exit_emitter__ = new EE() emitter.count = 0 emitter.emitted = {} } // Because this emitter is a global, we have to check to see if a // previous version of this library failed to enable infinite listeners. // I know what you're about to say. But literally everything about // signal-exit is a compromise with evil. Get used to it. if (!emitter.infinite) { emitter.setMaxListeners(Infinity) emitter.infinite = true } module.exports = function (cb, opts) { assert.equal(typeof cb, 'function', 'a callback must be provided for exit handler') if (loaded === false) { load() } var ev = 'exit' if (opts && opts.alwaysLast) { ev = 'afterexit' } var remove = function () { emitter.removeListener(ev, cb) if (emitter.listeners('exit').length === 0 && emitter.listeners('afterexit').length === 0) { unload() } } emitter.on(ev, cb) return remove } module.exports.unload = unload function unload () { if (!loaded) { return } loaded = false signals.forEach(function (sig) { try { process.removeListener(sig, sigListeners[sig]) } catch (er) {} }) process.emit = originalProcessEmit process.reallyExit = originalProcessReallyExit emitter.count -= 1 } function emit (event, code, signal) { if (emitter.emitted[event]) { return } emitter.emitted[event] = true emitter.emit(event, code, signal) } // { <signal>: <listener fn>, ... } var sigListeners = {} signals.forEach(function (sig) { sigListeners[sig] = function listener () { // If there are no other listeners, an exit is coming! // Simplest way: remove us and then re-send the signal. // We know that this will kill the process, so we can // safely emit now. var listeners = process.listeners(sig) if (listeners.length === emitter.count) { unload() emit('exit', null, sig) /* istanbul ignore next */ emit('afterexit', null, sig) /* istanbul ignore next */ process.kill(process.pid, sig) } } }) module.exports.signals = function () { return signals } module.exports.load = load var loaded = false function load () { if (loaded) { return } loaded = true // This is the number of onSignalExit's that are in play. // It's important so that we can count the correct number of // listeners on signals, and don't wait for the other one to // handle it instead of us. emitter.count += 1 signals = signals.filter(function (sig) { try { process.on(sig, sigListeners[sig]) return true } catch (er) { return false } }) process.emit = processEmit process.reallyExit = processReallyExit } var originalProcessReallyExit = process.reallyExit function processReallyExit (code) { process.exitCode = code || 0 emit('exit', process.exitCode, null) /* istanbul ignore next */ emit('afterexit', process.exitCode, null) /* istanbul ignore next */ originalProcessReallyExit.call(process, process.exitCode) } var originalProcessEmit = process.emit function processEmit (ev, arg) { if (ev === 'exit') { if (arg !== undefined) { process.exitCode = arg } var ret = originalProcessEmit.apply(this, arguments) emit('exit', process.exitCode, null) /* istanbul ignore next */ emit('afterexit', process.exitCode, null) return ret } else { return originalProcessEmit.apply(this, arguments) } }