1 files changed, 145 insertions, 0 deletions
diff --git a/src/util/timer.ts b/src/util/timer.ts
new file mode 100644
index 000000000..d3bb5d485
--- /dev/null
+++ b/src/util/timer.ts
@@ -0,0 +1,145 @@
+/*
+ This file is part of TALER
+ (C) 2017 GNUnet e.V.
+
+ TALER is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Cross-platform timers.
+ *
+ * NodeJS and the browser use slightly different timer API,
+ * this abstracts over these differences.
+ */
+
+/**
+ * Cancelable timer.
+ */
+export interface TimerHandle {
+  clear(): void;
+}
+
+class IntervalHandle {
+  constructor(public h: any) {
+  }
+
+  clear() {
+    clearInterval(this.h);
+  }
+}
+
+class TimeoutHandle {
+  constructor(public h: any) {
+  }
+
+  clear() {
+    clearTimeout(this.h);
+  }
+}
+
+/**
+ * Get a performance counter in milliseconds.
+ */
+export const performanceNow: () => number = (() => {
+  if (typeof process !== "undefined" && process.hrtime) {
+    return () => {
+      const t = process.hrtime();
+      return t[0] * 1e9 + t[1];
+    };
+  } else if (typeof "performance" !== "undefined") {
+    return () => performance.now();
+  } else {
+    return () => 0;
+  }
+})();
+
+/**
+ * Call a function every time the delay given in milliseconds passes.
+ */
+export function every(delayMs: number, callback: () => void): TimerHandle {
+  return new IntervalHandle(setInterval(callback, delayMs));
+}
+
+/**
+ * Call a function after the delay given in milliseconds passes.
+ */
+export function after(delayMs: number, callback: () => void): TimerHandle {
+  return new TimeoutHandle(setTimeout(callback, delayMs));
+}
+
+
+const nullTimerHandle = {
+  clear() {
+    // do nothing
+    return;
+  },
+};
+
+/**
+ * Group of timers that can be destroyed at once.
+ */
+export class TimerGroup {
+  private stopped: boolean = false;
+
+  private timerMap: { [index: number]: TimerHandle } = {};
+
+  private idGen = 1;
+
+  stopCurrentAndFutureTimers() {
+    this.stopped = true;
+    for (const x in this.timerMap) {
+      if (!this.timerMap.hasOwnProperty(x)) {
+        continue;
+      }
+      this.timerMap[x].clear();
+      delete this.timerMap[x];
+    }
+  }
+
+  after(delayMs: number, callback: () => void): TimerHandle {
+    if (this.stopped) {
+      console.warn("dropping timer since timer group is stopped");
+      return nullTimerHandle;
+    }
+    const h = after(delayMs, callback);
+    const myId = this.idGen++;
+    this.timerMap[myId] = h;
+
+    const tm = this.timerMap;
+
+    return {
+      clear() {
+        h.clear();
+        delete tm[myId];
+      },
+    };
+  }
+
+  every(delayMs: number, callback: () => void): TimerHandle {
+    if (this.stopped) {
+      console.warn("dropping timer since timer group is stopped");
+      return nullTimerHandle;
+    }
+    const h = every(delayMs, callback);
+    const myId = this.idGen++;
+    this.timerMap[myId] = h;
+
+    const tm = this.timerMap;
+
+    return {
+      clear() {
+        h.clear();
+        delete tm[myId];
+      },
+    };
+  }
+}