附录三 关于book.h

▶ 本书中用到的公用函数放到了头文件book.h中

 #ifndef __BOOK_H__
 #define __BOOK_H__
 #include <stdio.h>
 #include <stdlib.h>         // 自己加的
 #include "cuda_runtime.h"   // 自己加的

 static void HandleError( cudaError_t err, const char *file, int line )//定义报错函数，通过传入的返回值和文件名、行号来提示信息
 {
     if (err != cudaSuccess)
     {
         printf( "%s in %s at line %d\n", cudaGetErrorString( err ),file, line );
         exit( EXIT_FAILURE );
     }
 }
 #define HANDLE_ERROR( err ) (HandleError( err, __FILE__, __LINE__ ))// 将报错函数包装为宏，自动填塞文件名和行号

 #define HANDLE_NULL( a )/* 空指针报错函数，代码中malloc失败时报错 */              \
 {                                                                             \
     if (a == NULL)                                                            \
     {                                                                         \
         printf( "Host memory failed in %s at line %d\n", __FILE__, __LINE__ );\
         exit(EXIT_FAILURE);                                                   \
     }                                                                         \
 }

 template< typename T >// 泛型交换（全书都没用到？）
 void swap( T& a, T& b )
 {
     T t = a;
     a = b;
     b = t;
 }

 void* big_random_block( int size )//在主机中生成随机数组，无符号字符型
 {
     unsigned char *data = (unsigned char*)malloc( size );
     HANDLE_NULL( data );
     for (int i = ; i < size; data[i] = rand(), i++);
     return data;
 }

 int* big_random_block_int( int size )//在主机中生成随机数组，整型
 {
     int *data = (int*)malloc( size * sizeof(int) );
     HANDLE_NULL( data );
     for (int i = ; i < size; data[i] = rand(), i++);
     return data;
 }

 // 公用设备函数
 __device__ unsigned char value(float n1, float n2, int hue)
 {
     if (hue > )
         hue -= ;
     else if (hue < )
         hue += ;
     if (hue < )
         return (unsigned char)( * (n1 + (n2 - n1)*hue / ));
     if (hue < )
         return (unsigned char)( * n2);
     if (hue < )
         return (unsigned char)( * (n1 + (n2 - n1)*( - hue) / ));
     return (unsigned char)( * n1);
 }

 __global__ void float_to_color(unsigned char *optr, const float *outSrc)
 {
     int x = threadIdx.x + blockIdx.x * blockDim.x;
     int y = threadIdx.y + blockIdx.y * blockDim.y;
     int offset = x + y * blockDim.x * gridDim.x;

     float l = outSrc[offset];
     float s = ;
     int h = ( + (int)(360.0f * outSrc[offset])) % ;
     float m1, m2;

     if (l <= 0.5f)
         m2 = l * ( + s);
     else
         m2 = l + s - l * s;
     m1 =  * l - m2; 

     optr[offset *  + ] = value(m1, m2, h + );
     optr[offset *  + ] = value(m1, m2, h);
     optr[offset *  + ] = value(m1, m2, h - );
     optr[offset *  + ] = ;
 }

 __global__ void float_to_color( uchar4 *optr,const float *outSrc )
 {
     int x = threadIdx.x + blockIdx.x * blockDim.x;
     int y = threadIdx.y + blockIdx.y * blockDim.y;
     int offset = x + y * blockDim.x * gridDim.x;

     float l = outSrc[offset];
     float s = ;
     int h = ( + (int)(360.0f * outSrc[offset])) % ;
     float m1, m2;

     if (l <= 0.5f)
         m2 = l * ( + s);
     else
         m2 = l + s - l * s;
     m1 =  * l - m2;

     optr[offset].x = value(m1, m2, h + );
     optr[offset].y = value(m1, m2, h);
     optr[offset].z = value(m1, m2, h - );
     optr[offset].w = ;
 }

 // 有关线程的设置
 #if _WIN32
     //Windows threads.
     #include <windows.h>

     typedef HANDLE CUTThread;// 统一包装
     typedef unsigned (WINAPI *CUT_THREADROUTINE)(void *);

     #define CUT_THREADPROC unsigned WINAPI
     #define  CUT_THREADEND return 0

 #else
     //POSIX threads.
     #include <pthread.h>

     typedef pthread_t CUTThread;
     typedef void *(*CUT_THREADROUTINE)(void *);

     #define CUT_THREADPROC void
     #define  CUT_THREADEND
 #endif

 // 线程的创造，单线程结束，单线程销毁和多线程等待
 CUTThread start_thread( CUT_THREADROUTINE, void *data );
 void end_thread( CUTThread thread );
 void destroy_thread( CUTThread thread );
 void wait_for_threads( const CUTThread *threads, int num );

 #if _WIN32
     CUTThread start_thread(CUT_THREADROUTINE func, void *data)
     {
         return CreateThread(NULL, , (LPTHREAD_START_ROUTINE)func, data, , NULL);
     }

     void end_thread(CUTThread thread)
     {
         WaitForSingleObject(thread, INFINITE);
         CloseHandle(thread);
     }

     void destroy_thread( CUTThread thread )
     {
         TerminateThread(thread, );
         CloseHandle(thread);
     }

     void wait_for_threads(const CUTThread * threads, int num){
         WaitForMultipleObjects(num, threads, true, INFINITE);

         for(int i = ; i < num; i++)
             CloseHandle(threads[i]);
     }

 #else
     CUTThread start_thread(CUT_THREADROUTINE func, void * data)
     {
         pthread_t thread;
         pthread_create(&thread, NULL, func, data);
         return thread;
     }

     void end_thread(CUTThread thread)
     {
         pthread_join(thread, NULL);
     }

     void destroy_thread( CUTThread thread )
     {
         pthread_cancel(thread);
     }

     void wait_for_threads(const CUTThread * threads, int num)
     {
         for(int i = ; i < num; i++)
             end_thread( threads[i] );
     }
 #endif

 #endif  // __BOOK_H__