/*===========================================================================*
* fs_putnode *
*===========================================================================*/
PUBLIC int fs_putnode()
{
/* Find the inode specified by the request message and decrease its counter. */
int count;
struct dir_record *dir = NULL;
dir = get_dir_record(fs_m_in.REQ_INODE_NR);
release_dir_record(dir);
count = fs_m_in.REQ_COUNT;
if (count <= 0) return(EINVAL);
if (count > dir->d_count) {
printf("put_inode: count too high: %d > %d\n", count, dir->d_count);
return(EINVAL);
}
if (dir->d_count > 1)
dir->d_count = dir->d_count - count + 1;/*Keep at least one reference*/
release_dir_record(dir); /* Actual inode release, might be last reference */
return(OK);
}
/*===========================================================================*
* fs_mountpoint *
*===========================================================================*/
PUBLIC int fs_mountpoint()
{
/* This function looks up the mount point, it checks the condition whether
* the partition can be mounted on the inode or not.
*/
register struct dir_record *rip;
int r = OK;
/* Temporarily open the file. */
if ((rip = get_dir_record(fs_m_in.REQ_INODE_NR)) == NULL)
return(EINVAL);
if (rip->d_mountpoint)
r = EBUSY;
/* If the inode is not a dir returns error */
if ((rip->d_mode & I_TYPE) != I_DIRECTORY)
r = ENOTDIR;
release_dir_record(rip);
if (r == OK)
rip->d_mountpoint = TRUE;
return(r);
}
/*===========================================================================*
* fs_putnode *
*===========================================================================*/
PUBLIC int fs_putnode()
{
/* Find the inode specified by the request message and decrease its counter.
*/
int count;
struct dir_record *dir = (void *)0;
/* if (fs_m_in.REQ_INODE_INDEX >= 0 && */
/* fs_m_in.REQ_INODE_INDEX <= NR_DIR_RECORDS && */
/* ID_DIR_RECORD((dir_records + fs_m_in.REQ_INODE_INDEX)) == fs_m_in.REQ_INODE_NR) { */
/* dir = &dir_records[fs_m_in.REQ_INODE_INDEX]; */
/* /\* In this case the dir record by the dir record table *\/ */
/* } else { */
dir = get_dir_record(fs_m_in.REQ_INODE_NR);
/* Get dir record increased the counter. We must decrease it releasing
* it */
release_dir_record(dir);
if (dir == (void *)0) {
panic(__FILE__, "fs_putnode failed", NO_NUM);
}
count= fs_m_in.REQ_COUNT; /* I will check that the values of the count
* are the same */
if (count <= 0) {
printf("put_inode: bad value for count: %d\n", count);
panic(__FILE__, "fs_putnode failed", NO_NUM);
return EINVAL;
}
if (count > dir->d_count) {
printf("put_inode: count too high: %d > %d\n", count, dir->d_count);
panic(__FILE__, "fs_putnode failed", NO_NUM);
return EINVAL;
}
if (dir->d_count > 1)
dir->d_count = dir->d_count - count + 1; /* If the dir record should be released this
operation will bring the counter to 1.
The next function will further decreases it
releasing it completely. */
release_dir_record(dir); /* I finally release it */
return OK;
}
/*===========================================================================*
* fs_read *
*===========================================================================*/
int fs_read(void) {
int r, chunk, block_size;
int nrbytes;
cp_grant_id_t gid;
off_t position, f_size, bytes_left;
unsigned int off, cum_io;
int completed;
struct dir_record *dir;
r = OK;
/* Try to get inode according to its index */
dir = get_dir_record(fs_m_in.REQ_INODE_NR);
if (dir == NULL) return(EINVAL); /* no inode found */
position = fs_m_in.REQ_SEEK_POS_LO;
nrbytes = (unsigned) fs_m_in.REQ_NBYTES; /* number of bytes to read */
block_size = v_pri.logical_block_size_l;
gid = fs_m_in.REQ_GRANT;
f_size = dir->d_file_size;
rdwt_err = OK; /* set to EIO if disk error occurs */
cum_io = 0;
/* Split the transfer into chunks that don't span two blocks. */
while (nrbytes != 0) {
off = (unsigned int) (position % block_size);
chunk = MIN(nrbytes, block_size - off);
if (chunk < 0) chunk = block_size - off;
bytes_left = f_size - position;
if (position >= f_size) break; /* we are beyond EOF */
if (chunk > bytes_left) chunk = (int) bytes_left;
/* Read or write 'chunk' bytes. */
r = read_chunk(dir, cvul64(position), off, chunk, (unsigned) nrbytes,
gid, cum_io, block_size, &completed);
if (r != OK) break; /* EOF reached */
if (rdwt_err < 0) break;
/* Update counters and pointers. */
nrbytes -= chunk; /* bytes yet to be read */
cum_io += chunk; /* bytes read so far */
position += chunk; /* position within the file */
}
fs_m_out.RES_SEEK_POS_LO = position;
if (rdwt_err != OK) r = rdwt_err; /* check for disk error */
if (rdwt_err == END_OF_FILE) r = OK;
fs_m_out.RES_NBYTES = cum_io; /*dir->d_file_size;*/
release_dir_record(dir);
return(r);
}
/*===========================================================================*
* fs_access *
*===========================================================================*/
int fs_access()
{
struct dir_record *rip;
int r = OK;
/* Temporarily open the file whose access is to be checked. */
caller_uid = fs_m_in.REQ_UID;
caller_gid = fs_m_in.REQ_GID;
/* Temporarily open the file. */
if ( (rip = get_dir_record(fs_m_in.REQ_INODE_NR)) == NULL) {
printf("ISOFS(%d) get_dir_record by fs_access() failed\n", SELF_E);
return(EINVAL);
}
/* For now ISO9660 doesn't have permission control (read and execution to
* everybody by default. So the access is always granted. */
release_dir_record(rip); /* Release the dir record used */
return(r);
}
/*===========================================================================*
* fs_getdents *
*===========================================================================*/
int fs_getdents(void) {
struct dir_record *dir;
ino_t ino;
cp_grant_id_t gid;
size_t block_size;
off_t pos, block_pos, block, cur_pos, tmpbuf_offset, userbuf_off;
struct buf *bp;
struct dir_record *dir_tmp;
struct dirent *dirp;
int r,done,o,len,reclen;
char *cp;
char name[NAME_MAX + 1];
char name_old[NAME_MAX + 1];
/* Initialize the tmp arrays */
memset(name,'\0',NAME_MAX);
memset(name_old,'\0',NAME_MAX);
/* Get input parameters */
ino = fs_m_in.REQ_INODE_NR;
gid = fs_m_in.REQ_GRANT;
pos = fs_m_in.REQ_SEEK_POS_LO;
block_size = v_pri.logical_block_size_l;
cur_pos = pos; /* The current position */
tmpbuf_offset = 0;
userbuf_off = 0;
memset(getdents_buf, '\0', GETDENTS_BUFSIZ); /* Avoid leaking any data */
if ((dir = get_dir_record(ino)) == NULL) return(EINVAL);
block = dir->loc_extent_l; /* First block of the directory */
block += pos / block_size; /* Shift to the block where start to read */
done = FALSE;
while (cur_pos<dir->d_file_size) {
bp = get_block(block); /* Get physical block */
if (bp == NULL) {
release_dir_record(dir);
return(EINVAL);
}
block_pos = cur_pos % block_size; /* Position where to start read */
while (block_pos < block_size) {
dir_tmp = get_free_dir_record();
create_dir_record(dir_tmp,bp->b_data + block_pos,
block*block_size + block_pos);
if (dir_tmp->length == 0) { /* EOF. I exit and return 0s */
block_pos = block_size;
done = TRUE;
release_dir_record(dir_tmp);
} else { /* The dir record is valid. Copy data... */
if (dir_tmp->file_id[0] == 0)
strlcpy(name, ".", NAME_MAX + 1);
else if (dir_tmp->file_id[0] == 1)
strlcpy(name, "..", NAME_MAX + 1);
else {
/* Extract the name from the field file_id */
strncpy(name, dir_tmp->file_id,
dir_tmp->length_file_id);
name[dir_tmp->length_file_id] = 0;
/* Tidy up file name */
cp = memchr(name, ';', NAME_MAX);
if (cp != NULL) name[cp - name] = 0;
/*If no file extension, then remove final '.'*/
if (name[strlen(name) - 1] == '.')
name[strlen(name) - 1] = '\0';
}
if (strcmp(name_old, name) == 0) {
cur_pos += dir_tmp->length;
release_dir_record(dir_tmp);
continue;
}
strlcpy(name_old, name, NAME_MAX + 1);
/* Compute the length of the name */
cp = memchr(name, '\0', NAME_MAX);
if (cp == NULL) len = NAME_MAX;
else len= cp - name;
/* Compute record length */
reclen = offsetof(struct dirent, d_name) + len + 1;
o = (reclen % sizeof(long));
if (o != 0)
reclen += sizeof(long) - o;
/* If the new record does not fit, then copy the buffer
* and start from the beginning. */
if (tmpbuf_offset + reclen > GETDENTS_BUFSIZ) {
r = sys_safecopyto(VFS_PROC_NR, gid, userbuf_off,
(vir_bytes)getdents_buf, tmpbuf_offset);
if (r != OK)
panic("fs_getdents: sys_safecopyto failed: %d", r);
userbuf_off += tmpbuf_offset;
tmpbuf_offset= 0;
}
/* The standard data structure is created using the
* data in the buffer. */
dirp = (struct dirent *) &getdents_buf[tmpbuf_offset];
dirp->d_ino = (ino_t)(bp->b_data + block_pos);
dirp->d_off= cur_pos;
dirp->d_reclen= reclen;
memcpy(dirp->d_name, name, len);
dirp->d_name[len]= '\0';
tmpbuf_offset += reclen;
cur_pos += dir_tmp->length;
release_dir_record(dir_tmp);
}
block_pos += dir_tmp->length;
}
put_block(bp); /* release the block */
if (done == TRUE) break;
cur_pos += block_size - cur_pos;
block++; /* read the next one */
}
if (tmpbuf_offset != 0) {
r = sys_safecopyto(VFS_PROC_NR, gid, userbuf_off,
(vir_bytes) getdents_buf, tmpbuf_offset);
if (r != OK)
panic("fs_getdents: sys_safecopyto failed: %d", r);
userbuf_off += tmpbuf_offset;
}
fs_m_out.RES_NBYTES = userbuf_off;
fs_m_out.RES_SEEK_POS_LO = cur_pos;
release_dir_record(dir); /* release the inode */
return(OK);
}
