gdt.h

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#ifndef MEM_GDT_H
#define MEM_GDT_H

#include <stdint.h>

#define GDT_ENTRIES        6 
#define GDT_RING0_CODE_SEG 1 
#define GDT_RING0_DATA_SEG 2 
#define GDT_RING3_CODE_SEG 3 
#define GDT_RING3_DATA_SEG 4 
#define GDT_TASK_STATE_SEG 5 


typedef struct {
    uint16_t limit0_15  : 16; 
    uint32_t base0_23   : 24; 
    uint8_t  ac         :  1; 
    uint8_t  rw         :  1; 
    uint8_t  dc         :  1; 
    uint8_t  ex         :  1; 
    uint8_t  dt         :  1; 
    uint8_t  dpl        :  2; 
    uint8_t  pr         :  1; 
    uint8_t  limit16_19 :  4; 
    uint8_t  reserved   :  2; 
    uint8_t  sz         :  1; 
    uint8_t  gr         :  1; 
    uint8_t  base24_31  :  8; 
} __attribute__((packed)) gdt_entry_t;

void gdt_init_entry(size_t entry, uint32_t base, uint32_t limit);
void gdt_init();
uint16_t gdt_get_selector(size_t entry);

#endif