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#ifndef GDT_H
#define GDT_H

#include "types.h"

typedef struct {
	uint32_t link;
	
	uint32_t esp0;
	uint32_t ss0;
	
	uint32_t esp1;
	uint32_t ss1;
	
	uint32_t esp2;
	uint32_t ss2;
	
	uint32_t cr3;
	
	uint32_t eip;
	uint32_t eflags;
	
	uint32_t eax;
	uint32_t ecx;
	uint32_t edx;
	uint32_t ebx;
	uint32_t esp;
	uint32_t ebp;
	uint32_t esi;
	uint32_t edi;
	
	uint32_t es;
	uint32_t cs;
	uint32_t ss;
	uint32_t ds;
	uint32_t fs;
	uint32_t gs;
	
	uint32_t ldt;
	
	uint16_t trap;
	uint16_t iomap;
} __attribute__((packed)) tss_entry;

typedef struct {
	uint16_t limit_low;
	uint16_t base_low;
	uint8_t base_mid;
	uint16_t flags;
	uint8_t base_high;
} __attribute__((packed)) gdt_entry;

typedef struct {
	uint16_t limit;
	gdt_entry* base;
} __attribute__((packed)) gdt_ptr;

#define gdt_entry_init(b, l, f) { \
	.base_low = (b & 0xffff), \
	.base_mid = (b >> 16 & 0xff), \
	.base_high = (b >> 24 & 0xff), \
	.limit_low = (l & 0xffff), \
	.flags = (f | (l >> 8 & 0x0f00))}

#define tss_entry_init(e, s, c, d) { \
	.esp0 = e, \
	.ss0 = s, \
	.cs = c, \
	.ss = d, \
	.ds = d, \
	.es = d, \
	.fs = d, \
	.gs = d}

void gdt_init();

#endif