banker.h

操作系统中的经典问题：银行家算法

#include <vector>
#include <list>
#include <string>
#include <iostream>
#include <fstream>

using namespace std;

list< vector<int> > g_already, g_needed;//已经分配矩阵、仍需要分配矩阵
vector<int> g_total, g_allot, g_free;//总的资源g_total、已分配资源g_allot和剩余资源g_free
vector<int> empty;//空的资源队列
vector<string> g_res;//资源类型
int g_res_size;//资源数目
list< vector<int> >::iterator g_already_ptr;
list< vector<int> >::iterator g_needed_ptr;
const int MAX_INSTRUCTION = 5; //指令轮转周期，即每个线程在执行周期内最多执行的指令数目

//初始化计算机
void init()
{
	ifstream computer("computer.bin");
	if (!computer.is_open())
	{
		cout << "The BIOS can not find the computer.bin, the computer will shut down!";
		exit(1);
	}
	char tmp[20];
	while (!computer.eof())
	{
		computer.getline(tmp, sizeof(tmp));
		g_res.push_back(tmp);
		computer.getline(tmp, sizeof(tmp));
		g_total.push_back( atoi(tmp) );
	}

	g_res_size = (int)g_res.size();
	//初始化变量empty
	for (int i=0; i < g_res_size; i++)
		empty.push_back(0);
	g_allot = empty;
	g_free = g_total;
}


//显示资源的内容
void what_are_res()
{
	cout << "There are " << g_res_size << " kind(s) of resource(s) in this computer:" <<endl;
	cout << "ID\tName\tNum" <<endl;

	for (int i=0; i < g_res_size; i++)
	{
		cout << i << "\t" << g_res[i] << "\t" << g_total[i] <<endl;
	}
}

//显示资源的分配状态
void how_res()
{
	list< vector<int> >::iterator ptr;
	vector<int>::iterator ptr2;

	cout << "Total resource(s): "<<endl;
	for (ptr2 = g_total.begin(); ptr2 != g_total.end(); ptr2++)
	{
		cout << *ptr2 << "\t";
	}
	cout << endl;

	cout << "Alloted resource(s): "<<endl;
	for (ptr2 = g_allot.begin(); ptr2 != g_allot.end(); ptr2++)
	{
		cout << *ptr2 << "\t";
	}
	cout << endl;

	cout << "Free resource(s): "<<endl;
	for (ptr2 = g_free.begin(); ptr2 != g_free.end(); ptr2++)
	{
		cout << *ptr2 << "\t";
	}
	cout << endl;

	cout << "The resource(s) already alloted:" << endl;
	for (ptr = g_already.begin(); ptr != g_already.end(); ptr++)
	{
		//vector<int> tmp = *ptr;
		for (unsigned int i=0; i < (*ptr).size(); i++)
		{
			cout << (*ptr)[i] << "\t";
		}
		cout << endl;
	}

	cout << "The resource(s) needed to allot:" << endl;
	for (ptr = g_needed.begin(); ptr != g_needed.end(); ptr++)
	{
		//vector<int> tmp = *ptr;
		for (unsigned int i=0; i < (*ptr).size(); i++)
		{
			cout << (*ptr)[i] << "\t";
		}
		cout << endl;
	}
}