Inside Macintosh: Files /

Chapter 5 - Disk Initialization Manager

Summary of the Disk Initialization Manager

Pascal Summary

Data Types

HFS Defaults Record

TYPE HFSDefaults =
RECORD
   sigWord:    PACKED ARRAY[0..1] OF Byte;   {signature word}
   abSize:     LongInt;                      {allocation block size in bytes}
   clpSize:    LongInt;                      {clump size in bytes}
   nxFreeFN:   LongInt;                      {next free file number}
   btClpSize:  LongInt;                      {B*-tree clump size in bytes}
   rsrv1:      Integer;                      {reserved}
   rsrv2:      Integer;                      {reserved}
   rsrv3:      Integer;                      {reserved}
END;

Routines

Loading and Unloading the Disk Initialization Manager

PROCEDURE DILoad;
PROCEDURE DIUnload;

Initializing a Disk

FUNCTION DIBadMount		(where: Point; evtMessage: LongInt): Integer;

Low-Level Disk-Initialization Routines

FUNCTION DIFormat		(drvNum: Integer): OSErr;
FUNCTION DIVerify		(drvNum: Integer): OSErr;
FUNCTION DIZero			(drvNum: Integer; volName: Str255): OSErr;

C Summary

Data Types

HFS Defaults Record

struct HFSDefaults {
      char        sigWord[2];    /*signature word*/
      long        abSize;        /*allocation block size in bytes*/
      long        clpSize;       /*clump size in bytes*/
      long        nxFreeFN;      /*next free file number*/
      long        btClpSize;     /*B-Tree clump size in bytes*/
      short       rsrv1;         /*reserved*/
      short       rsrv2;         /*reserved*/
      short       rsrv3;         /*reserved*/
};
typedef struct HFSDefaults HFSDefaults;

Routines

Loading and Unloading the Disk Initialization Package

pascal void DILoad	(void);
pascal void DIUnload	(void);

Initializing a Disk

pascal short DIBadMount	(Point where, long evtMessage);

Low-Level Disk-Initialization Routines

pascal OSErr DIFormat	(short drvNum);
pascal OSErr DIVerify	(short drvNum);
pascal OSErr DIZero	(short drvNum, const Str255 volName);

Assembly-Language Summary

Data Structures

HFSDefaults Data Structure

0	sigWord	word	signature word
2	abSize	long	allocation block size in bytes
6	clpSize	long	clump size in bytes
10	nxFreeFN	long	next free file number
14	btClpSize	long	B*-tree clump size in bytes
18	rsrv1	word	reserved
20	rsrv2	word	reserved
22	rsrv3	word	reserved

Trap Macros

Trap Macro Requiring Routine Selectors

_Pack2 
Selector
Routine

$0000
DIBadMount

$0002
DILoad

$0004
DIUnload

$0006
DIFormat

$0008
DIVerify

$000A
DIZero

Global Variables

FmtDefaults

long

Pointer to substitute values for hierarchical volume directories.

Result Codes

[no name]	2	Disk in specified drive is already mounted
[no name]	1	User canceled initializing
noErr	0	No error
ioErr	-36	I/O error
paramErr	-50	Drive number specified is bad
volOnLinErr	-55	Volume is already online
nsDrvErr	-56	No such drive
noMacDskErr	-57	Disk is not a Macintosh disk
extFSErr	-58	Disk has external file system
badMDBErr	-60	Master directory block is bad
lastDskErr	-64	Last of the range of low-level disk errors
firstDskErr	-84	First of the range of low-level disk errors
memFullErr	-108	Not enough memory