Prepare cscore for merge into allwpilib.

cscore/examples/usbstream/usbstream.cpp

@@ -0,0 +1,35 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2017-2018 FIRST. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include <cstdio>
+
+#include <llvm/raw_ostream.h>
+
+#include "cscore.h"
+
+int main() {
+  llvm::outs() << "hostname: " << cs::GetHostname() << '\n';
+  llvm::outs() << "IPv4 network addresses:\n";
+  for (const auto& addr : cs::GetNetworkInterfaces())
+    llvm::outs() << "  " << addr << '\n';
+  cs::UsbCamera camera{"usbcam", 0};
+  camera.SetVideoMode(cs::VideoMode::kMJPEG, 320, 240, 30);
+  cs::MjpegServer mjpegServer{"httpserver", 8081};
+  mjpegServer.SetSource(camera);
+
+  CS_Status status = 0;
+  cs::AddListener(
+      [&](const cs::RawEvent& event) {
+        llvm::outs() << "FPS=" << camera.GetActualFPS()
+                     << " MBPS=" << (camera.GetActualDataRate() / 1000000.0)
+                     << '\n';
+      },
+      cs::RawEvent::kTelemetryUpdated, false, &status);
+  cs::SetTelemetryPeriod(1.0);
+
+  std::getchar();
+}