summaryrefslogtreecommitdiff
path: root/deps/npm/node_modules/asap/asap.js
diff options
context:
space:
mode:
Diffstat (limited to 'deps/npm/node_modules/asap/asap.js')
-rw-r--r--deps/npm/node_modules/asap/asap.js64
1 files changed, 64 insertions, 0 deletions
diff --git a/deps/npm/node_modules/asap/asap.js b/deps/npm/node_modules/asap/asap.js
new file mode 100644
index 0000000000..3a27c8cee7
--- /dev/null
+++ b/deps/npm/node_modules/asap/asap.js
@@ -0,0 +1,64 @@
+"use strict";
+
+var rawAsap = require("./raw");
+var freeTasks = [];
+
+/**
+ * Calls a task as soon as possible after returning, in its own event, with
+ * priority over IO events. An exception thrown in a task can be handled by
+ * `process.on("uncaughtException") or `domain.on("error")`, but will otherwise
+ * crash the process. If the error is handled, all subsequent tasks will
+ * resume.
+ *
+ * @param {{call}} task A callable object, typically a function that takes no
+ * arguments.
+ */
+module.exports = asap;
+function asap(task) {
+ var rawTask;
+ if (freeTasks.length) {
+ rawTask = freeTasks.pop();
+ } else {
+ rawTask = new RawTask();
+ }
+ rawTask.task = task;
+ rawTask.domain = process.domain;
+ rawAsap(rawTask);
+}
+
+function RawTask() {
+ this.task = null;
+ this.domain = null;
+}
+
+RawTask.prototype.call = function () {
+ if (this.domain) {
+ this.domain.enter();
+ }
+ var threw = true;
+ try {
+ this.task.call();
+ threw = false;
+ // If the task throws an exception (presumably) Node.js restores the
+ // domain stack for the next event.
+ if (this.domain) {
+ this.domain.exit();
+ }
+ } finally {
+ // We use try/finally and a threw flag to avoid messing up stack traces
+ // when we catch and release errors.
+ if (threw) {
+ // In Node.js, uncaught exceptions are considered fatal errors.
+ // Re-throw them to interrupt flushing!
+ // Ensure that flushing continues if an uncaught exception is
+ // suppressed listening process.on("uncaughtException") or
+ // domain.on("error").
+ rawAsap.requestFlush();
+ }
+ // If the task threw an error, we do not want to exit the domain here.
+ // Exiting the domain would prevent the domain from catching the error.
+ this.task = null;
+ this.domain = null;
+ freeTasks.push(this);
+ }
+};