模拟LINUX文件系统及终端

/*************************************************************************************** fs.cpp 辅助函数，执行命令函数会被反复调用的函数 ***************************************************************************************/ #include "fs.h" #include <iostream.h> #include <fstream.h> #include <string.h> #include <stdio.h> #include <io.h> #include <windows.h> void fs::creatFS() { cout << "正在创建文件系统 ..." << endl; int i, j; fstream FILE("VirtualDisk", ios::binary|ios::in|ios::out); //申请磁盘空间 if (!FILE) { cerr << "磁盘空间无法创建!" << endl; return; } FILE.seekp(0, ios::beg); //申请空间，先将其都填充为" " for (i = 0; i < blockNum * blockSize; i++) //共申请Block_Num个磁盘块 { FILE.write(" ", sizeof(char)); } FILE.seekp(0, ios::beg); //填充超级块区 Super.freeBlock = 101867; //用于储存文件的磁盘块为101867块 Super.freeInode = 1023; FILE.write((char*)&Super, sizeof(super)); FILE.seekp(1016, ios::cur); //把文件的写指针从当前位置向后移1016个字节 for (i = 0; i < inodeNum; i++) //填充inode位图 { if (i == 0) inodeBMP[i] = 1; else inodeBMP[i] = 0; FILE.write((char*)&inodeBMP[i], sizeof(int)); } for (i = 0; i < 533; i++) //填充block位图，前533块已被占用 { blockBMP[i] = 1; FILE.write((char*)&blockBMP[i], sizeof(int)); } for (i = 533; i < blockNum; i++) //后面的磁盘块都未被占用 { blockBMP[i] = 0; FILE.write((char*)&blockBMP[i], sizeof(int)); } Inode[0].isFile = 0; //写根目录 strcpy(Inode[0].name, "Z:"); //根目录命名为Z:盘 Inode[0].firstBlock = -1; //根目录不额外占用磁盘块 Inode[0].length = 0; Inode[0].index = 0; Inode[0].parent = -1; Inode[0].childNum = 0; //子节点个数为0 for (j = 0; j < 15; j++) //将每个目录的子节点赋为-1 { Inode[0].child[j] = -1; } GetLocalTime(&Inode[0].TIME); //获取当前系统时间 FILE.write((char*)&Inode[0], sizeof(inode)); for(i = 1; i < inodeNum; i++) //填充Inode区 { Inode[i].isFile = -1; Inode[i].index = i; for (j = 0; j < 15; j++) //将每个目录的子节点赋为-1 { Inode[i].child[j] = -1; } FILE.write((char*)&Inode[i], sizeof(inode)); } FILE.close(); curIndex = 0; //初始化当前目录为根目录 curInode = &Inode[curIndex]; //当前i-node索引指针 strcpy(curPath, curInode->name); // strcat(curPath, "/"); system("cls"); cout << "成功创建!" << endl; Sleep(1500); system("cls"); } void fs::load() { fstream FILE("VirtualDisk", ios::binary|ios::in|ios::out); //申请虚拟磁盘空间 if (!FILE) { cerr << "没有找到虚拟磁盘" << endl; return; } FILE.seekp(0, ios::beg); //文件指针回到起始处 FILE.read((char*)&Super, sizeof(super)); FILE.seekg(1016, ios::cur); int i; for (i = 0; i < inodeNum; i++) { FILE.read((char*)&inodeBMP[i], sizeof(int)); } for (i = 0; i < 533; i++) { FILE.read((char*)&blockBMP[i], sizeof(int)); } for (i = 0; i < inodeNum; i++) { FILE.read((char*)&Inode[i], sizeof(inode)); } FILE.close(); curIndex = 0; //初始化当前目录为根目录 curInode = &Inode[curIndex]; //当前i-node索引指针 strcpy(curPath, curInode->name); // strcat(curPath, "/"); } void fs::save() { fstream FILE("VirtualDisk", ios::binary|ios::in|ios::out); int i = 0; FILE.seekp(0, ios::beg); FILE.write((char*)&Super, sizeof(super)); FILE.seekp(1016, ios::cur); for (i = 0; i < inodeNum; i++) { FILE.write((char*)&inodeBMP[i], sizeof(int)); } for (i = 0; i < 533; i++) { FILE.write((char*)&blockBMP[i], sizeof(int)); } for (i = 0; i < inodeNum; i++) { FILE.write((char*)&Inode[i], sizeof(inode)); } FILE.close(); } int fs::find(char * name, int parent) //搜索该文件或目录是否已经存在 { int i, temp; struct inode * Parent = &Inode[parent]; for (i = 0; i < 15; i++) { if(inodeBMP[Parent->child[i]] == 1) //使用Bitmap来判断该子节点是否存在 { temp = Parent->child[i]; if (strcmp(name, Inode[temp].name) == 0) return temp; } } return -1; } int fs::subfind(char * name, int parent) { int work, i = 0; inode * parentInode = &Inode[parent]; //for (int i = 0; i < 15; i++) while (i < 15) { if (inodeBMP[parentInode->child[i]] == 1) { work = parentInode->child[i]; if (strcmp(name, Inode[work].name) == 0) return i; } i++; } return -1; } char * fs::getAbsolutePath(int index) { char * absolutePath = new char; char * temp = new char; int parent; if (!index) { strcpy(absolutePath, "Z:"); return absolutePath; } else { parent = index; while (parent != -1) { if (parent == index) { strcpy(absolutePath, Inode[parent].name); parent = Inode[parent].parent; } else { strcpy(temp, Inode[parent].name); strcat(temp, "/"); strcat(temp, absolutePath); strcpy(absolutePath, temp); parent = Inode[parent].parent; } } return absolutePath; } } char * fs::getName(char * path) { char * temp = new char; char * rtnName = new char; int length = strlen(path); int i = 0; int j = 0; temp = strchr(path, '/'); //strchr函数返回第一次出现字符的位置指针 if (!temp) //相对路径或根目录 { return path; } else //完整路径 { //找到最后一个文件名 while(* path != '\0') //j为最后一个'/'的位置 { path++; i++; if(* path == '/') j = i; } rtnName = path - length + j + 1; //当前文件或目录名 return rtnName; } } int fs::getParentIndex(char * path) { int i, j, length, parent; i = j = 0; length = strlen(path); int Curr_Path_Num=0; //记录与name相同的文件或目录的数目 int Same_Path_Inode[15]; //记录与name相同的文件或目录的inode号 char * temp = new char; char * Curr_Temp = new char; char * Parent_Temp = new char; char * Path_Parent = new char; char * Parent_Name = new char; temp = strchr(path, '/'); if (!strcmp(path,"Z:")) //根目录情况 { return -1; //path为根目录，其索引值为-1 } else { if (!temp) //相对路径情况 { return curIndex; } else //绝对路径情况 { while(*path != '\0') //查找其父目录 { path++; i++; if (*path == '/') j = i; } strncpy(Path_Parent, path - length, j); Path_Parent[j] = '\0'; //Path_Parent为父目录名 Parent_Name = getName(Path_Parent); for (int k = 0; k < 15; k++) //初始化Same_Path_Inode[15]数组 { Same_Path_Inode[k] = 0; } for (int l=0; l < inodeNum; l++) { if (!strcmp(Parent_Name, Inode[l].name)) //计算与name相同的文件名数目及inode号 { Curr_Path_Num++; Same_Path_Inode[Curr_Path_Num] = Inode[l].index; } } for (int m = 1; m <= Curr_Path_Num; m++) { parent = Same_Path_Inode[m]; do { if (parent == Same_Path_Inode[m]) { strcpy(Curr_Temp, Inode[parent].name); parent = Inode[parent].parent; } else { strcpy(Parent_Temp, Inode[parent].name); strcat(Parent_Temp, "/"); strcat(Parent_Temp, Curr_Temp); strcpy(Curr_Temp, Parent_Temp); parent = Inode[parent].parent; } } while (parent != -1); if (!strcmp(Curr_Temp, Path_Parent) && Inode[Same_Path_Inode[m]].isFile == 0) { return Same_Path_Inode[m]; //找到父目录 } } return -2; //找不到父目录