px4-firmware/apps/examples/elf/tests/helloxx/hello++2.cpp

/////////////////////////////////////////////////////////////////////////////
// examples/elf/tests/helloxx/hello++2.c
//
//   Copyright (C) 2012 Gregory Nutt. All rights reserved.
//   Author: Gregory Nutt <gnutt@nuttx.org>
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in
//    the documentation and/or other materials provided with the
//    distribution.
// 3. Neither the name NuttX nor the names of its contributors may be
//    used to endorse or promote products derived from this software
//    without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
// OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
// AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
/////////////////////////////////////////////////////////////////////////////
//
// This is an another trivial version of "Hello, World" design.  It illustrates
//
// - Building a C++ program to use the C library
// - Basic class creation
// - NO Streams
// - NO Static constructor and destructors
//
/////////////////////////////////////////////////////////////////////////////

/////////////////////////////////////////////////////////////////////////////
// Included Files
/////////////////////////////////////////////////////////////////////////////

#include <cstdio>

/////////////////////////////////////////////////////////////////////////////
// Classes
/////////////////////////////////////////////////////////////////////////////

class CThingSayer
{
  const char *szWhatToSay;
public:
  CThingSayer(void)
    {
      printf("CThingSayer::CThingSayer: I am!\n");
      szWhatToSay = (const char*)NULL;
    }
 
  ~CThingSayer(void)
    {
      printf("CThingSayer::~CThingSayer: I cease to be\n");
      if (szWhatToSay)
	{
	  printf("CThingSayer::~CThingSayer: I will never say '%s' again\n",
		 szWhatToSay);
	}
      szWhatToSay = (const char*)NULL;
    }

  void Initialize(const char *czSayThis)
    {
      printf("CThingSayer::Initialize: When told, I will say '%s'\n",
	     czSayThis);
      szWhatToSay = czSayThis;
    }

  void SayThing(void)
    {
      printf("CThingSayer::SayThing: I am now saying '%s'\n", szWhatToSay);
    }
};

/////////////////////////////////////////////////////////////////////////////
// Public Functions
/////////////////////////////////////////////////////////////////////////////

int main(int argc, char **argv)
{
  CThingSayer *MyThingSayer;

  printf("main: Started.  Creating MyThingSayer\n");

  // Create an instance of the CThingSayer class
  // We should see the message from constructor, CThingSayer::CThingSayer(),

  MyThingSayer = new CThingSayer;
  printf("main: Created MyThingSayer=0x%08lx\n", (long)MyThingSayer);

  // Tell MyThingSayer that "Hello, World!" is the string to be said

  printf("main: Calling MyThingSayer->Initialize\n");;
  MyThingSayer->Initialize("Hello, World!");

  // Tell MyThingSayer to say the thing we told it to say

  printf("main: Calling MyThingSayer->SayThing\n");;
  MyThingSayer->SayThing();

  // We should see the message from the destructor,
  // CThingSayer::~CThingSayer(), AFTER we see the following

  printf("main: Destroying MyThingSayer\n");
  delete MyThingSayer;

  printf("main: Returning\n");;
  return 0;
}