/*
* namei()
*
* is used by most simple commands to get the inode of a specified name.
* Open, link etc use their own routines, but this is enough for things
* like 'chmod' etc.
*/
struct m_inode * namei(const char * pathname)
{
const char * basename;
int inr,dev,namelen;
struct m_inode * dir;
struct buffer_head * bh;
struct dir_entry * de;
if (!(dir = dir_namei(pathname,&namelen,&basename)))
return NULL;
if (!namelen) /* special case: '/usr/' etc */
return dir;
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
iput(dir);
return NULL;
}
inr = de->inode;
dev = dir->i_dev;
brelse(bh);
iput(dir);
dir=iget(dev,inr);
if (dir) {
dir->i_atime=CURRENT_TIME;
dir->i_dirt=1;
}
return dir;
}
int do_unlink(char *name)
{
char *basename;
int namelen;
struct m_inode *dir,*inode;
// struct buffer_head *bh;
struct dir_entry *de;
if(!(dir = dir_namei(name,&basename,&namelen)))
{ //no such file or direntry
return -ENOENT;
}
if(!namelen)
{
iput(dir);
return -ENOENT;
}
//删除目录项
if((del_entry(dir,basename,namelen,&de)) != 0)
{
printk("no such file");
iput(dir);
return -ENOENT;
}
if(!(inode = iget(dir->i_dev,de->inode_num)))
{
iput(dir);
return -ENOENT;
}
//not permit to del direntry
if(S_ISDIR(inode->i_mode))
{
iput(inode);
iput(dir);
return -EPERM;
}
if(--(inode->i_count))
{
printk("deleting using file\n");
return -EMLINK;
}
de->inode_num = 0;
inode->i_dirt = 1;
iput(inode);
iput(dir);
printk("delete file successful\n");
return 0;
}
static errcode_t open_namei(ext2_filsys fs, ext2_ino_t root, ext2_ino_t base,
const char *pathname, size_t pathlen, int follow,
int link_count, char *buf, ext2_ino_t *res_inode)
{
const char *base_name;
int namelen;
ext2_ino_t dir, inode;
errcode_t retval;
#ifdef NAMEI_DEBUG
printf("open_namei: root=%lu, dir=%lu, path=%*s, lc=%d\n",
root, base, pathlen, pathname, link_count);
#endif
retval = dir_namei(fs, root, base, pathname, pathlen,
link_count, buf, &base_name, &namelen, &dir);
if (retval) return retval;
if (!namelen) {
*res_inode=dir;
return 0;
}
retval = ext2fs_lookup (fs, dir, base_name, namelen, buf, &inode);
if (retval)
return retval;
if (follow) {
retval = follow_link(fs, root, dir, inode, link_count,
buf, &inode);
if (retval)
return retval;
}
#ifdef NAMEI_DEBUG
printf("open_namei: (link_count=%d) returns %lu\n",
link_count, inode);
#endif
*res_inode = inode;
return 0;
}
/*
* open_namei()
*
* namei for open - this is in fact almost the whole open-routine.
*/
int open_namei(const char * pathname, int flag, int mode,
struct m_inode ** res_inode)
{
const char * basename;
int inr,dev,namelen;
struct m_inode * dir, *inode;
struct buffer_head * bh;
struct dir_entry * de;
if ((flag & O_TRUNC) && !(flag & O_ACCMODE))
flag |= O_WRONLY;
mode &= 0777 & ~current->umask;
mode |= I_REGULAR;
if (!(dir = dir_namei(pathname,&namelen,&basename)))
return -ENOENT;
if (!namelen) { /* special case: '/usr/' etc */
if (!(flag & (O_ACCMODE|O_CREAT|O_TRUNC))) {
*res_inode=dir;
return 0;
}
iput(dir);
return -EISDIR;
}
bh = find_entry(&dir,basename,namelen,&de);
if (!bh) {
if (!(flag & O_CREAT)) {
iput(dir);
return -ENOENT;
}
if (!permission(dir,MAY_WRITE)) {
iput(dir);
return -EACCES;
}
inode->i_mode = mode;
bh = add_entry(dir,basename,namelen,&de);
if (!bh) {
inode->i_nlinks--;
iput(inode);
iput(dir);
return -ENOSPC;
}
bh->b_dirt = 1;
brelse(bh);
iput(dir);
*res_inode = inode;
return 0;
}
inr = de->inode;
dev = dir->i_dev;
brelse(bh);
iput(dir);
if (flag & O_EXCL)
return -EEXIST;
if (!(inode=iget(dev,inr)))
return -EACCES;
if ((S_ISDIR(inode->i_mode) && (flag & O_ACCMODE)) ||
!permission(inode,ACC_MODE(flag))) {
iput(inode);
return -EPERM;
}
inode->i_atime = CURRENT_TIME;
if (flag & O_TRUNC)
truncate(inode);
*res_inode = inode;
return 0;
}
static errcode_t open_namei(cmfs_filesys *fs,
uint64_t root,
uint64_t base,
const char *pathname,
size_t pathlen,
int follow,
int link_count,
char *buf,
uint64_t *res_inode)
{
const char *basename;
int namelen;
uint64_t dir, inode;
errcode_t ret;
#ifdef NAMIE_DEBUG
printf("%s:%d root=%lu, dir=%lu, path=%*s, lc=%d\n",
__func__, __LINE__,
root, base, pathlen, pathname, link_count);
#endif
ret = dir_namei(fs,
root,
base,
pathname,
pathlen,
link_count,
buf,
&basename,
&namelen,
&dir);
if (ret)
return ret;
/* special case: '/usr/' etc */
if (!namelen) {
*res_inode = dir;
return 0;
}
ret = cmfs_lookup(fs,
dir,
basename,
namelen,
buf,
&inode);
if (ret)
return ret;
if (follow) {
ret = follow_link(fs,
root,
dir,
inode,
link_count,
buf,
&inode);
if (ret)
return ret;
}
#ifdef NAMEI_DEBUG
printf("%s:%d (link_count=%d) returns %lu\n",
link_count, inode);
#endif
*res_inode = inode;
return 0;
}
