/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * Copyright (c) 1992 NeXT Computer, Inc. * * Intel386 Family: Segment descriptors. * * HISTORY * * 29 March 1992 ? at NeXT * Created. */ /* * Code segment descriptor. */ typedef struct code_desc { unsigned short limit00; unsigned short base00; unsigned char base16; unsigned char type :5, #define DESC_CODE_EXEC 0x18 #define DESC_CODE_READ 0x1a dpl :2, present :1; unsigned char limit16 :4, :2, opsz :1, #define DESC_CODE_16B 0 #define DESC_CODE_32B 1 granular:1; #define DESC_GRAN_BYTE 0 #define DESC_GRAN_PAGE 1 unsigned char base24; } code_desc_t; /* * Data segment descriptor. */ typedef struct data_desc { unsigned short limit00; unsigned short base00; unsigned char base16; unsigned char type :5, #define DESC_DATA_RONLY 0x10 #define DESC_DATA_WRITE 0x12 dpl :2, present :1; unsigned char limit16 :4, :2, stksz :1, #define DESC_DATA_16B 0 #define DESC_DATA_32B 1 granular:1; unsigned char base24; } data_desc_t; /* * LDT segment descriptor. */ typedef struct ldt_desc { unsigned short limit00; unsigned short base00; unsigned char base16; unsigned char type :5, #define DESC_LDT 0x02 :2, present :1; unsigned char limit16 :4, :3, granular:1; unsigned char base24; } ldt_desc_t; #include <architecture/i386/sel.h> /* * Call gate descriptor. */ typedef struct call_gate { unsigned short offset00; sel_t seg; unsigned int argcnt :5, :3, type :5, #define DESC_CALL_GATE 0x0c dpl :2, present :1, offset16:16; } call_gate_t; /* * Trap gate descriptor. */ typedef struct trap_gate { unsigned short offset00; sel_t seg; unsigned int :8, type :5, #define DESC_TRAP_GATE 0x0f dpl :2, present :1, offset16:16; } trap_gate_t; /* * Interrupt gate descriptor. */ typedef struct intr_gate { unsigned short offset00; sel_t seg; unsigned int :8, type :5, #define DESC_INTR_GATE 0x0e dpl :2, present :1, offset16:16; } intr_gate_t;