Inside Macintosh: Networking /

Chapter 10 - Link-Access Protocol (LAP) Manager

Summary of the LAP Manager

Pascal Summary

Constants

CONST
   {Transition Queue transition types}
   ATTransOpen          =        0;       {AppleTalk has been opened}
   ATTransClose         =        2;       {AppleTalk is about to close}
   ATTransClosePrep     =        3;       {permission to close AppleTalk}
   ATTransCancelClose   =        4;       {cancel the ClosePrep transition}

{To use the following six constants, you must first declare them in your }
{ application. They are not included in the MPW interface files.}
   ATTransNetworkTransition   =  5;       {change in network connection for }
                                          { Apple Remote Access (ARA)}
   ATTransNameChangeTellTask  =  6;       {flagship name change}
   ATTransNameChangeAskTask   =  7;       {permission to change flagship }
                                          { name}
   ATTransCancelNameChange    =  8;       {cancel flagship name change}
   ATTransCableChange         =  'rnge';  {change in cable range}
   ATTransSpeedChange         =  'sped';  {change in CPU speed}

Data Types

AppleTalk Transition Queue Entry

TYPE ATQEntry = 
RECORD
   qLink:      ATQEntryPtr;      {next queue entry}
   qType:      Integer;          {reserved}
   CallAddr:   ProcPtr;          {pointer to your routine}
END;

ATQEntryPtr = ^ATQEntry;

Routines

Adding and Removing AppleTalk Transition Queue Entries

FUNCTION LAPAddATQ(theATQEntry: ATQEntryPtr): OSErr;
FUNCTION LAPRmvATQ(theATQEntry: ATQEntryPtr): OSErr;

Notifying Routines When Your Application-Defined Transition Occurs

PROCEDURE ATEvent(event: LongInt; infoPtr: Ptr);
FUNCTION ATPreFlightEvent(event: LongInt; cancel: LongInt; infoPtr: Ptr):
OSErr;

C Summary

Constants

/*LAP Manager parameter constants*/
#define LAPprotType LAP.protType
#define LAPwdsPointer LAP.LAPptrs.wdsPointer
#define LAPhandler LAP.LAPptrs.handler

enum {                                    /*AppleTalk Transition Queue */
                                          /* transition types*/
ATTransOpen                =     0,       /*AppleTalk has opened*/
ATTransClose               =     2,       /*AppleTalk is about to close*/
ATTransClosePrep           =     3,       /*permission to close AppleTalk*/
ATTransCancelClose         =     4,       /*cancel ClosePrep transition*/

/*To use the following six constants, you must first define them in */
/* your application. They are not defined in the MPW interface files.*/
ATTransNetworkTransition   =     5,       /*change in network connection */
                                          /* for ARA*/
ATTransNameChangeTellTask  =     6,       /*flagship name change*/
ATTransNameChangeAskTask   =     7,       /*permission to change */
                                          /* flagship name*/
ATTransCancelNameChange    =     8,       /*cancel flagship name change*/
ATTransCableChange         =     'rnge',  /*change in cable range*/ 
ATTransSpeedChange         =     'sped',  /*change in CPU speed*/
};

Data Types

AppleTalk Transition Queue Entry

struct ATQEntry {
   struct ATQEntry   *qLink;        /*reserved*/
   short             qType;         /*reserved*/
   ProcPtr           CallAddr;      /*pointer to your routine*/
};

typedef struct ATQEntry ATQEntry;
typedef ATQEntry *ATQEntryPtr;

Routines

Adding and Removing AppleTalk Transition Queue Entries

pascal OSErr LAPAddATQ(ATQEntryPtr theATQEntry); 
pascal OSErr LAPRmvATQ(ATQEntryPtr theATQEntry);

Notifying Routines When Your Application-Defined Transition Occurs

pascal void ATEvent(long event, Ptr infoPtr);
pascal OSErr ATPreFlightEvent(long event, long cancel, Ptr 
infoPtr); 

Assembly-Language Summary

Constants

;routine selectors to attach and detach an 802.2 protocol handler
L802Attach           EQU    21         ;attach an 802.2 protocol handler
L802Detach           EQU    22         ;detach an 802.2 protocol handler

;miscellaneous LAP Manager values
LAPMgrPtr            EQU   $B18        ;entry point for LAP Manager
LAPMgrCall           EQU   2           ;offset to LAP routines
LAddAEQ              EQU   23          ;LAPAddATQ routine selector
LRmvAEQ              EQU   24          ;LAPRmvATQ routine selector

Data Structures

AppleTalk Transition Queue Entry Data Structure

0	AeQQLink	long	next queue entry
4	AeQQType	word	reserved
6	AeQCallAddr	long	pointer to your transition event handler routine

Result Codes

noErr	0	No error, or unrecognized event code
qErr	-1	Queue element not found