[ion] Add a host tool to generate random events

Change-Id: I5a4db0ed5dcf2a1ae8743c2d3cda8dde6bd5962d

ion/src/shared/tools/event_generator.cpp

@@ -0,0 +1,47 @@
+#include <iostream>
+#include <fstream>
+#include <random>
+#include <cstdio>
+#include <ion/events.h>
+
+void writeEventsToFile(std::ofstream & file, int numberOfEvents, std::mt19937 & rng) {
+  std::uniform_int_distribution<int> distribution(0,Ion::Events::Event::k_numberOfEvents);
+
+  int i = numberOfEvents;
+  while (i > 0) {
+    int prEventId = distribution(rng);
+    Ion::Events::Event e(prEventId);
+    if (e.isValid()) {
+      i--;
+      file << (char)(prEventId);
+    }
+  }
+}
+
+int main(int argc, char * argv[]) {
+  if (argc != 3) {
+    std::cerr << "Usage: event_generator <count> <length_avg>" << std::endl;
+    return -1;
+  }
+
+  std::random_device r;
+  std::mt19937 mt(r());
+
+  int count = std::stoi(argv[1]);
+  int lengthAvg = std::stoi(argv[2]);
+  int lengthStdDev = lengthAvg;
+
+  std::normal_distribution<> lengthDistribution(lengthAvg, lengthStdDev);
+
+  for (int i=0; i<count; i++) {
+    char buffer[32];
+    sprintf(buffer, "scenario_%04d.bin", i);
+    std::string fileName(buffer);
+    std::ofstream file;
+    file.open(fileName);
+    writeEventsToFile(file, lengthDistribution(mt), mt);
+    file.close();
+  }
+
+  return 0;
+}