ZXing.h Example File

 // -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
 /*
  *  Copyright 2013 ZXing authors All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 #ifndef __ZXING_H_
 #define __ZXING_H_

 #define ZXING_ARRAY_LEN(v) ((int)(sizeof(v)/sizeof(v[0])))
 #define ZX_LOG_DIGITS(digits) \
     ((digits == 8) ? 3 : \
      ((digits == 16) ? 4 : \
       ((digits == 32) ? 5 : \
        ((digits == 64) ? 6 : \
         ((digits == 128) ? 7 : \
          (-1))))))

 #ifndef ZXING_DEBUG
 #define ZXING_DEBUG 0
 #endif

 #include <limits>
 #include "common/Types.h"

 #if defined(_WIN32) || defined(_WIN64)

 #include <float.h>
 #include <cmath>

 namespace zxing {
 inline bool isnan_z(float v) {return std::isnan(v) != 0;}
 inline bool isnan_z(double v) {return std::isnan(v) != 0;}
 }

 #elif (__cplusplus >= 201103L)
 #include <cmath>
 namespace zxing {
 inline bool isnan_z(float v) {
     return std::isnan(v);
 }
 inline bool isnan_z(double v) {
     return std::isnan(v);
 }
 }
 #elif(__STDC_VERSION__ >= 199901L)
 #include <math.h>
 namespace zxing {
 inline bool isnan_z(float v) {
     return isnan(v);
 }
 inline bool isnan_z(double v) {
     return isnan(v);
 }
 }
 #else
 namespace zxing {
 inline bool isnan_z(float v) {
     volatile float d = v;
     return d != d;
 }
 inline bool isnan_z(double v) {
     volatile double d = v;
     return d != d;
 }
 }
 #endif

 namespace zxing {
         inline float nan() {return std::numeric_limits<float>::quiet_NaN();}
 }

 #if ZXING_DEBUG

 #include <iostream>
 #include <string>

 using std::cout;
 using std::cerr;
 using std::endl;
 using std::flush;
 using std::string;
 using std::ostream;

 #if ZXING_DEBUG_TIMER

 #include <sys/time.h>

 namespace zxing {

 class DebugTimer {
 public:
   DebugTimer(char const* string_) : chars(string_) {
     gettimeofday(&start, 0);
   }

   DebugTimer(std::string const& string_) : chars(0), string(string_) {
     gettimeofday(&start, 0);
   }

   void mark(char const* string) {
     struct timeval end;
     gettimeofday(&end, 0);
     int diff =
       (end.tv_sec - start.tv_sec)*1000*1000+(end.tv_usec - start.tv_usec);

     cerr << diff << " " << string << '\n';
   }

   void mark(std::string string) {
     mark(string.c_str());
   }

   ~DebugTimer() {
     if (chars) {
       mark(chars);
     } else {
       mark(string.c_str());
     }
   }

 private:
   char const* const chars;
   std::string string;
   struct timeval start;
 };

 }

 #define ZXING_TIME(string) DebugTimer __timer__ (string)
 #define ZXING_TIME_MARK(string) __timer__.mark(string)

 #endif

 #endif // ZXING_DEBUG

 #ifndef ZXING_TIME
 #define ZXING_TIME(string) (void)0
 #endif
 #ifndef ZXING_TIME_MARK
 #define ZXING_TIME_MARK(string) (void)0
 #endif

 #endif