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/* AsyncSCSIPresent.c */ |
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/* |
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* AsyncSCSIPresent.c |
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* Copyright © 1992-94 Apple Computer Inc. All Rights Reserved. |
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*/ |
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#include <OSUtils.h> |
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#include <Traps.h> |
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#ifndef _SCSIAtomic |
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/* |
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* This is needed if you don't have Universal Headers. |
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*/ |
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#define _SCSIAtomic 0xA089 |
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#endif |
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|
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Boolean AsyncSCSIPresent(void); |
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static Boolean TrapAvailable( |
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short theTrap |
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); |
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|
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Boolean |
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AsyncSCSIPresent(void) |
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{ |
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return (TrapAvailable(_SCSIAtomic)); |
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} |
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|
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/* |
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* TrapAvailable (see Inside Mac VI 3-8) |
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*/ |
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#define NumToolboxTraps() ( \ |
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(NGetTrapAddress(_InitGraf, ToolTrap) \ |
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== NGetTrapAddress(0xAA6E, ToolTrap)) \ |
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? 0x200 : 0x400 \ |
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) |
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#define GetTrapType(theTrap) ( \ |
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(((theTrap) & 0x0800) != 0) ? ToolTrap : OSTrap \ |
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) |
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|
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static Boolean |
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TrapAvailable( |
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short theTrap |
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) |
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{ |
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TrapType trapType; |
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|
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trapType = GetTrapType(theTrap); |
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if (trapType == ToolTrap) { |
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theTrap &= 0x07FF; |
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if (theTrap >= NumToolboxTraps()) |
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theTrap = _Unimplemented; |
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} |
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return ( |
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NGetTrapAddress(theTrap, trapType) |
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!= NGetTrapAddress(_Unimplemented, ToolTrap) |
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); |
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} |