format.c

操作系统课程设计

/*初始化磁盘格式化程序format.c*/
#include <stdio.h>
#include "filesys.h"
#include <stdlib.h>
#include <string.h>



format()
{
	struct inode *inode;
	struct direct dir_buf [BLOCKSIZ/(DIRSIZ+2)];
	struct pwd passwd[BLOCKSIZ/(PWDSIZ+4)];
	struct filsys filsys;
	unsigned int block_buf[BLOCKSIZ/sizeof(int)];
	char *buf;
	int i, j;



/*creat the file system file */
	fd = fopen("filesystem", "w+b");//我修改了"r+w+b"为"w+b"
	buf = (char *)malloc((DINODEBLK+FILEBLK+2)*BLOCKSIZ*sizeof(char));
	if(buf == NULL)
	{
		printf ("\nfile system file creat failed! \n");
		exit(0);
	}
	fseek(fd, 0, SEEK_SET);
	fwrite(buf, (DINODEBLK+FILEBLK+2)*BLOCKSIZ*sizeof(char), 1, fd);
	/* 0.initialize the passwd */
	pwd[0].p_uid = 2116; pwd[0].p_gid = 03;
	strcpy(pwd[0].password, "dddd");
	pwd[1].p_uid = 2117; pwd[1].p_gid = 03;
	strcpy(pwd[1].password, "bbbb");
	pwd[2].p_uid = 2118; pwd[2].p_gid = 04;
	strcpy(pwd[2].password, "abcd");
	pwd[3].p_uid = 2119; pwd[3].p_gid = 04;
	strcpy(pwd[3].password, "cccc");
	pwd[4].p_uid = 2220; pwd[4].p_gid = 05;
	strcpy(pwd[4].password, "eeee");

	passwd[0].p_uid=2116;passwd[0].p_gid=03;
    strcpy(passwd[0].password,"dddd");
    passwd[1].p_uid=2117;passwd[1].p_gid=03;
    strcpy(passwd[1].password,"bbbb");
    passwd[2].p_uid=2118;passwd[2].p_gid=04;
    strcpy(passwd[2].password,"abcd");
    passwd[3].p_uid=2119;passwd[3].p_gid=04;
    strcpy(passwd[3].password,"cccc");
    passwd[4].p_uid=2220;passwd[4].p_gid=05;
    strcpy(passwd[4].password,"eeee");
/* 1.creat the main directory and its sub dir etc and the file password */
	inode = iget(0);	/* 0 empty dinode id */
	inode->di_mode	= DIEMPTY;
	iput(inode);
	inode = iget(1);    /* 1 main dir id */
	inode->di_number = 1;
	inode->di_mode = DEFAULTMODE|DIDIR;
	inode->di_size = 3*(DIRSIZ+2);
	inode->di_addr[0] = 0;    /* block 0# is used by the main directory */
	strcpy(dir_buf[0].d_name, "..");
	dir_buf[0].d_ino = 1;
	strcpy(dir_buf[1].d_name,".");
	dir_buf[1].d_ino = 1;
	strcpy(dir_buf[2].d_name, "etc");
	dir_buf[2].d_ino = 2;
	fseek(fd, DATASTART, SEEK_SET);
	fwrite(dir_buf, 3*(DIRSIZ+2), 1, fd);
	iput(inode);
	inode=iget(2);/* 2 etc dir id */
	inode ->di_number =1;
	inode->di_mode=DEFAULTMODE|DIDIR;
	inode->di_size=3 * (DIRSIZ+2);
	inode->di_addr[0] = 1;    /* block 1# is used by the etc */
	strcpy (dir_buf[0].d_name, "..");
	dir_buf[0].d_ino=1;
	strcpy(dir_buf[1].d_name, ".");//我修改了".."为"."
	dir_buf[1].d_ino=2;
	strcpy(dir_buf[2].d_name, "password");
	dir_buf[2].d_ino=3;
	fseek(fd, DATASTART+BLOCKSIZ*1, SEEK_SET);
	fwrite (dir_buf, 3* (DIRSIZ+2), 1, fd);
	iput(inode);
	inode=iget(3);    /* 3 password id */
	inode->di_number= 1;
	inode->di_mode=DEFAULTMODE|DIFILE;
	inode->di_size=BLOCKSIZ;
	inode->di_addr[0]=2;	/* block 2# is used by the password */
	for (i=5; i<PWDNUM; i++)
	{	passwd[i].p_uid=0;
		passwd[i].p_gid=0;
		strcpy(passwd[i].password,"	");
	}
	fseek(fd, DATASTART+2*BLOCKSIZ, SEEK_SET);
	fwrite(passwd, BLOCKSIZ, 1, fd);
	iput(inode);

/* 2. initialize the superblock */
	filsys.s_isize = DINODEBLK;
	filsys.s_fsize = FILEBLK;
	filsys.s_ninode = DINODEBLK*BLOCKSIZ/DINODESIZ-4;
	filsys.s_nfree = FILEBLK-3;
	for(i=0; i<NICINOD; i++)
	{
	/*begin with 4, 0,1,2,3, is used by main, etc, password */
		filsys.s_inode[i] = 4+i;
	}
	filsys.s_pinode = 0;
	filsys.s_rinode = NICINOD+4;

/*修改后的成组链法超级块中是3-52号块，栈顶是3*/

	for(i=0; i<NICINOD; i++)
	{
		filsys.s_free[NICINOD-1-i] = i+3;
	}
	for(j=i+3; BLOCKSIZ-j>=NICFREE; j+=NICFREE)
	{
		for(i=0; i<NICFREE; i++)
		{
			block_buf[NICFREE-1-i] = j+i;
		}
		block_buf[NICFREE] = NICFREE;
		fseek(fd, DATASTART+BLOCKSIZ*(j-2), SEEK_SET);
		fwrite(block_buf, BLOCKSIZ, 1, fd);
	}
	i = BLOCKSIZ-j;
	for(j=j; j<BLOCKSIZ; j++)
	{
		block_buf[BLOCKSIZ-1-j] = j;
	}
	block_buf[NICFREE] = i;
	fseek(fd, DATASTART+BLOCKSIZ*(FILEBLK-i-3), SEEK_SET);
	fwrite(block_buf, BLOCKSIZ, 1, fd);


	filsys.s_pfree = NICFREE-1;
	fseek(fd, BLOCKSIZ, SEEK_SET);
	fwrite(&filsys, sizeof(struct filsys), 1, fd);
}