c++ - C语言 如何调用 pthread_create 里函数的参数?

Question

1.使用pthread，调用的函数的参数是class中的，该如何处理?

2.代码如下

#include<Windows.h>
#include <pthread.h> 
#include<stdlib.h>
#include <time.h>
#include<stdio.h>
#include<conio.h>
#define KEY_UP 'w'
#define KEY_DOWN 's'
#define KEY_LEFT 'a'
#define KEY_RIGHT 'd' 
#define FIRE 'j' 

class Player {
private:
    int positionX;
    int positionY;
    int positionA;
    int positionB;
public:
    void SetPositionX(int x) { positionX = x; } 
    void SetPositionY(int y) { positionY = y; }
    int GetPositionX() { return positionX; }
    int GetPositionY() { return positionY; }
    int m, n; //子弹坐标
};

void SetPosition(int x, int y) 
{
    COORD coord; 
    coord.X = 2 * x; 
    coord.Y = y;

    HANDLE handle; 
    handle = GetStdHandle(STD_OUTPUT_HANDLE); 
    SetConsoleCursorPosition(handle,coord); 
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
    CONSOLE_CURSOR_INFO cursor_info = {1, 0};  
    SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &cursor_info);
}

void *Controller(Player &pl) 
{
    int direction;
    if (_kbhit()) { //_kbhit()为true当且仅当用户按下键盘
        switch (_getch()) { //_getch()返回用户按下的那个按键，注意使用小写
            //根据玩家的输入进行移动
        case KEY_UP:
            if (pl.GetPositionY() == 1  )  { 
            break;
            }
            else {
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf(" "); 
                pl.SetPositionY(pl.GetPositionY() - 1); //
                SetPosition(pl.GetPositionX(), pl.GetPositionY()); //改变光标位置到改变后的位置
                printf("○"); //进行玩家的移动
                direction = 1;
            }
            break;
        case KEY_DOWN:
            if (pl.GetPositionY() == 21  )  { 
            break;
            }
            else {
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf(" ");
                pl.SetPositionY(pl.GetPositionY() + 1);
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf("○");
                direction = 2;
            }
            break;
        case KEY_LEFT:
            if (pl.GetPositionX() == 1  )  { 
            break;
            }
            else {
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf(" ");
                pl.SetPositionX(pl.GetPositionX() - 1);
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf("○");
                direction = 3;
            }
            break;
        case KEY_RIGHT:
            if (pl.GetPositionX() == 37 )  { 
            break;
            }
            else {
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf(" ");
                pl.SetPositionX(pl.GetPositionX() + 1);
                SetPosition(pl.GetPositionX(), pl.GetPositionY());
                printf("○");
                direction = 4;
            }
            break;
        default:break;
        }
    }
}


int main()
{
    int  pth1, loop01;
    pthread_t threads; 
    Player player, enemy; //声明一个自定义的玩家类型变量
    srand((unsigned)time(NULL));
    player.SetPositionX(rand()%30+2);
    player.SetPositionY(rand()%15+2); //设置初始坐标
    enemy.SetPositionX(rand()%30+2);
    enemy.SetPositionY(rand()%15+2);
    while (1) //游戏循环
    {                                                   //问题在此
        pth1 = pthread_create(&threads, NULL, Controller, (void*)Player &player);
    }                                                   //参数该如何调用?
    system("pause");
    return 0;
}

---

---

3.报错如下

E:\Workspace\C\Game test\problem.cpp: In function 'int main()':
E:\Workspace\C\Game test\problem.cpp:119:67: error: expected primary-expression
before '&' token
   pth1 = pthread_create(&threads, NULL, Controller, (void*)Player &player);
                                                                   ^

---

Answer 1

void *Controller(void* p) 
{
    Player &pl = *(Player*)p;
    ...
}

int main()
{       ...
        pth1 = pthread_create(&threads, NULL, Controller, (void*)&player);
        ...
}

It compiles in my case, but it’s a bit ugly

Answer 2

pth1 = pthread_create(&threads, NULL, Controller, &player);