examples: Remove heap allocation from C++ examples

Cleanup of UPM C++ examples.  Switched from heap allocation to
stack allocation when possible.  This simplifies the samples since it
removes the need for explicit memory management.  A script was used to
identify and replace pointer use.  To simplify the replace script, I
re-formatted the C++ examples using the UPM .clang-format file.
Unfortuantely this changes the look of the UPM C++ examples to a large
degree.  However, examples will now have a standard look/feel and
uniform formatting.

    * Ran clang-format w/provided UPM .clang-format file
    * Removed new's/delete's whenever possible (left those in interface
      examples)
    * Added IIO sensor library implementation of callback void* arg
    * Converted all sleeps to upm defined delays (added header when
      necessary)
    * Scrubbed CXX example includes

Signed-off-by: Noel Eck <noel.eck@intel.com>

examples/c++/ads1x15-ads1015.cxx

@@ -29,11 +29,13 @@
  */
 
 #include <fstream>
+#include <iostream>
 #include <string>
 #include <thread>
-#include <unistd.h>
 
 #include "ads1015.hpp"
+#include "ads1x15.hpp"
+#include "upm_utilities.h"
 
 using namespace std;
 using namespace upm;
@@ -41,39 +43,41 @@ using namespace upm;
 bool running = true; // Controls main read/write loop
 
 // Thread function
-void stop()
+void
+stop()
 {
-    sleep(10);
+    upm_delay(10);
     running = false;
 }
 
-int main()
+int
+main()
 {
     //! [Interesting]
-    long id = 0; // Sample number
+    long id = 0;                        // Sample number
     string fileName = "./ads1015.data"; // Output filename
     ofstream f;
 
     // Initialize and configure the ADS1015
-    ADS1015 *ads1015 = new upm::ADS1015(0, 0x48);
+    ADS1015 ads1015(0, 0x48);
 
     // Put the ADC into differential mode for pins A0 and A1
-    ads1015->getSample(ADS1X15::DIFF_0_1);
+    ads1015.getSample(ADS1X15::DIFF_0_1);
 
     // Set the gain based on expected VIN range to -/+ 2.048 V
     // Can be adjusted based on application to as low as -/+ 0.256 V, see API
     // documentation for details
-    ads1015->setGain(ADS1X15::GAIN_TWO);
+    ads1015.setGain(ADS1X15::GAIN_TWO);
 
     // Set the sample rate to 3300 samples per second (max) and turn on continuous
     // sampling
-    ads1015->setSPS(ADS1015::SPS_3300);
-    ads1015->setContinuous(true);
+    ads1015.setSPS(ADS1015::SPS_3300);
+    ads1015.setContinuous(true);
 
     // Enable exceptions from the output stream
     f.exceptions(ofstream::failbit | ofstream::badbit);
     // Open the file
-    try{
+    try {
         f.open(fileName);
 
         // Output formatting
@@ -81,19 +85,18 @@ int main()
         f.precision(7);
 
         // Start the thread that will stop logging after 10 seconds
-        thread timer (stop);
+        thread timer(stop);
 
         // Read sensor data and write it to the output file every ms
-        while(running){
-            f << id++ << " " << ads1015->getLastSample() << endl;
-            usleep(1000);
+        while (running) {
+            f << id++ << " " << ads1015.getLastSample() << endl;
+            upm_delay_us(1000);
         }
 
         // Clean-up and exit
         timer.join();
         f.close();
-        delete ads1015;
-    } catch (ios_base::failure &e) {
+    } catch (ios_base::failure& e) {
         cout << "Failed to write to file: " << e.what() << endl;
         return 1;
     }
@@ -101,4 +104,3 @@ int main()
     //! [Interesting]
     return 0;
 }
-