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The fsObject structure is used to store information about files and directories.
It contains information like the date when the object was last altered, its protection
bits, its unique node number and specifically for files things like its size and the
location of its data.
Objects are stored in ObjectContainers. Each
ObjectContainer holds a variable number of Objects which belong to a specific directory.
| Field |
Type |
Description |
| owneruid |
UWORD |
Not used at the moment, and are set to zero. This field, and the
ownergid field will be used later on for multi-user support. |
| ownergid |
UWORD |
See owneruid. |
| objectnode |
NODE |
This field contains the node number which uniquely identifies this
object. The node number can be looked up to determine in which block an object is
stored. |
| protection |
ULONG |
Contains the Object's protection bits. When creating a new object this
fields is set to 0x0000000F, which means bits R, W, E and D are set (note that this is
opposite to what is used by AmigaDOS). |
| data |
BLCK |
(files only). The first block which contains data stored in this
file. The rest of the data can be located by looking up this block number in the
B-Tree stored in the BNodeContainers. If this field is
zero then the file is empty and the size field must be zero as well. |
| size |
ULONG |
(files only). The size of the file in bytes. Zero indicates
an empty file, and in that case the data field must be zero as well. |
| hashtable |
BLCK |
(directories only). Points to the HashTable
block which belongs to this directory. A directory always has a HashTable block
associated with it, even if the directory is empty. |
| firstdirblock |
BLCK |
(directories only). This points to the first ObjectContainer
block which belongs to this directory. If the directory is empty then this field is
zero. |
| datemodified |
ULONG |
This field is used to hold the date of the last modification of an
Object. It holds the number of seconds elapsed since 1-1-1978, which is enough room
for about 136 years. The modification date is updated whenever a file is changed or,
in the case of a directory, an object which is a direct descendant is added or removed
from the directory. |
| bits |
UBYTE |
See the defines below. At the moment this field can be checked to
see if you're dealing with a directory or file Object. Two bits are reserved for
future use, one for links and one for deletion status. These bits, and all other
unused bits are always zero. |
| name |
String |
After the main structure the name of the Object is stored. It is
zero terminated. The name can of course vary in length, which means this structure
can differ in size depending on the length of the name and comment fields. |
| comment |
String |
Directly following the name of the Object is the comment field.
This fields is zero terminated, even if there is no comment. |
struct fsObject {
UWORD owneruid;
UWORD ownergid;
NODE objectnode;
ULONG protection;
union {
struct {
BLCK data;
ULONG size;
} file;
struct {
BLCK hashtable;
BLCK firstdirblock;
} dir;
} object;
ULONG datemodified;
UBYTE bits; /* see defines below */
UBYTE name[0];
UBYTE comment[0];
};
#define OTYPE_DELETED (32)
#define OTYPE_LINK (64)
#define OTYPE_DIR (128)
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