// 设置当前的目录
int
vfs_set_curdir(struct inode *dir) {
int ret = 0;
lock_cfs();
struct inode *old_dir;
if ((old_dir = get_cwd_nolock()) != dir) { // 得到当前的工作目录的inode
if (dir != NULL) {
uint32_t type;
if ((ret = vop_gettype(dir, &type)) != 0) {
goto out;
}
if (!S_ISDIR(type)) {
ret = -E_NOTDIR;
goto out;
}
vop_ref_inc(dir);
}
set_cwd_nolock(dir);
if (old_dir != NULL) {
vop_ref_dec(old_dir);
}
}
out:
unlock_cfs();
return ret;
}
int
sfs_unlink(struct inode *dp, char *name){
struct inode *ip;
struct sfs_dirent de;
uint off;
vop_ilock(dp);
// Cannot unlink "." or "..".
if(namecmp(name, ".") == 0 || namecmp(name, "..") == 0)
goto bad;
if((ip = vop_dirlookup(dp, name, &off)) == 0)
goto bad;
vop_ilock(ip);
if(vop_getnlink(ip) < 1)
panic("unlink: nlink < 1");
if(vop_gettype(ip) == T_DIR && !vop_isdirempty(ip)){
vop_iunlockput(ip);
goto bad;
}
memset(&de, 0, sizeof(de));
if(vop_write(dp, (char*)&de, off, sizeof(de)) != sizeof(de))
panic("unlink: writei");
if(vop_gettype(ip) == T_DIR){
vop_link_dec(dp);
vop_iupdate(dp);
}
vop_iunlockput(dp);
vop_link_dec(ip);
vop_iupdate(ip);
vop_iunlockput(ip);
return 0;
bad:
vop_iunlockput(dp);
return -1;
}
/*
* sfs_fstat - Return nlinks/block/size, etc. info about a file. The pointer is a pointer to struct stat;
*/
static int
sfs_fstat(struct inode *node, struct stat *stat) {
int ret;
memset(stat, 0, sizeof(struct stat));
if ((ret = vop_gettype(node, &(stat->st_mode))) != 0) {
return ret;
}
struct sfs_disk_inode *din = vop_info(node, sfs_inode)->din;
stat->st_nlinks = din->nlinks;
stat->st_blocks = din->blocks;
stat->st_size = din->size;
return 0;
}
/*
* Called for fstat().
* Set the type and the size.
* The link count for a device is always 1.
*/
static int
dev_fstat(struct inode *node, struct stat *stat) {
int ret;
memset(stat, 0, sizeof(struct stat));
if ((ret = vop_gettype(node, &(stat->st_mode))) != 0) {
return ret;
}
struct device *dev = vop_info(node, device);
stat->st_nlinks = 1;
stat->st_blocks = dev->d_blocks;
stat->st_size = stat->st_blocks * dev->d_blocksize;
return 0;
}
static int pipe_inode_fstat(struct inode *node, struct stat *stat)
{
int ret;
memset(stat, 0, sizeof(struct stat));
if ((ret = vop_gettype(node, &(stat->st_mode))) != 0) {
return ret;
}
struct pipe_inode *pin = vop_info(node, pipe_inode);
stat->st_nlinks = 1;
stat->st_blocks = 0;
stat->st_size =
pipe_state_size(pin->state, pin->pin_type == PIN_WRONLY);
return 0;
}
static int
sfs_fstat(struct inode *node, struct stat *stat) {
int ret;
memset(stat, 0, sizeof(struct stat));
if ((ret = vop_gettype(node, &(stat->st_mode))) != 0) {
return ret;
}
struct sfs_disk_inode *din = vop_info(node, sfs_inode)->din;
stat->st_nlinks = din->nlinks;
stat->st_blocks = din->blocks;
if (din->type != SFS_TYPE_DIR) {
stat->st_size = din->fileinfo.size;
}
else {
stat->st_size = (din->dirinfo.slots + 2) * sfs_dentry_size;
}
return 0;
}
