arg_t _getfsys(void)
{
struct mount *m = fs_tab_get(dev);
if (m == NULL || m->m_dev == NO_DEVICE) {
udata.u_error = ENXIO;
return (-1);
}
return uput((char *) m->m_fs, (char *) buf, sizeof(struct filesys));
}
/* Validblk panics if the given block number is not a valid
* data block for the given device.
*/
void validblk(uint16_t dev, blkno_t num)
{
struct mount *mnt;
fsptr devptr;
mnt = fs_tab_get(dev);
if(mnt == NULL || !(devptr = mnt->m_fs) || devptr->s_mounted == 0) {
panic("validblk: not mounted");
return;
}
if(num < devptr->s_isize || num >= devptr->s_fsize)
panic("validblk: invalid blk");
}
fsptr getdev(uint16_t dev)
{
struct mount *mnt;
fsptr devfs;
time_t t;
mnt = fs_tab_get(dev);
if (!mnt || !(devfs = mnt->m_fs) || devfs->s_mounted) {
panic("getdev: bad dev");
/* Return needed to persuade SDCC all is ok */
return NULL;
}
rdtime(&t);
devfs->s_time = (uint32_t)t;
devfs->s_timeh = (uint8_t)(t >> 32);
devfs->s_fmod = true;
((bufptr)devfs)->bf_dirty = true;
return devfs;
}
inoptr kn_open(char *namep, inoptr *parent)
{
staticfast inoptr wd; /* the directory we are currently searching. */
staticfast inoptr ninode;
inoptr temp;
staticfast char *name;
name = namep;
#ifdef DEBUG
kprintf("kn_open(\"%s\")\n", name);
#endif
if(*name == '/')
wd = udata.u_root;
else
wd = udata.u_cwd;
i_ref(ninode = wd);
i_ref(ninode);
for(;;)
{
if(ninode)
magic(ninode);
/* cheap way to spot rename inside yourself */
if (udata.u_rename == ninode)
udata.u_rename = NULLINODE;
/* See if we are at a mount point */
if(ninode)
ninode = srch_mt(ninode);
while(*name == '/') /* Skip(possibly repeated) slashes */
++name;
if(!*name) /* No more components of path? */
break;
if(!ninode){
udata.u_error = ENOENT;
goto nodir;
}
i_deref(wd);
wd = ninode;
if(getmode(wd) != F_DIR){
udata.u_error = ENOTDIR;
goto nodir;
}
if(!(getperm(wd) & OTH_EX)){
udata.u_error = EPERM;
goto nodir;
}
/* See if we are going up through a mount point */
if((wd == udata.u_root || (wd->c_num == ROOTINODE && wd->c_dev != root_dev)) &&
name[0] == '.' && name[1] == '.' &&
(name[2] == '/' || name[2] == '\0')){
if (wd == udata.u_root) {
ninode = wd;
name += 2;
continue;
}
temp = fs_tab_get(wd->c_dev)->m_fs->s_mntpt;
++temp->c_refs;
i_deref(wd);
wd = temp;
}
ninode = srch_dir(wd, name);
while(*name != '/' && *name)
++name;
}
if(parent)
*parent = wd;
else
i_deref(wd);
if(!(parent || ninode))
udata.u_error = ENOENT;
return ninode;
nodir:
if(parent)
*parent = NULLINODE;
i_deref(wd);
return NULLINODE;
}
inoptr i_open(uint16_t dev, uint16_t ino)
{
struct dinode *buf;
inoptr nindex, j;
bool isnew = false;
if(!validdev(dev))
panic("i_open: bad dev");
if(!ino){ /* ino==0 means we want a new one */
isnew = true;
ino = i_alloc(dev);
if(!ino) {
udata.u_error = ENOSPC;
return NULLINODE;
}
}
/* Maybe make this DEBUG only eventually - the fs_tab_get cost
is higher than ideal */
if(ino < ROOTINODE || ino >= (fs_tab_get(dev)->m_fs->s_isize - 2) * 8) {
kputs("i_open: bad inode number\n");
return NULLINODE;
}
nindex = NULLINODE;
for(j=i_tab; j<i_tab+ITABSIZE; j++){
if(!j->c_refs) // free slot?
nindex = j;
if(j->c_dev == dev && j->c_num == ino) {
nindex = j;
goto found;
}
}
/* Not already in the table. */
if(!nindex){ /* No unrefed slots in inode table */
udata.u_error = ENFILE;
return(NULLINODE);
}
buf =(struct dinode *)bread(dev,(ino>>3)+2, 0);
memcpy((char *)&(nindex->c_node), (char *)&(buf[ino & 0x07]), 64);
brelse(buf);
nindex->c_dev = dev;
nindex->c_num = ino;
nindex->c_magic = CMAGIC;
found:
if(isnew) {
if(nindex->c_node.i_nlink || nindex->c_node.i_mode & F_MASK)
goto badino;
} else {
if(!(nindex->c_node.i_nlink && nindex->c_node.i_mode & F_MASK))
goto badino;
}
nindex->c_refs++;
return nindex;
badino:
kputs("i_open: bad disk inode\n");
return NULLINODE;
}