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#ifndef MELVIX_SYSTEM_H
#define MELVIX_SYSTEM_H
#include "graphics/graphics.h"
/**
* Initialize the basic features of the OS
*/
void init();
/**
* The ASM registers as packed structure
*/
typedef struct __attribute__ ((packed)) {
unsigned short di, si, bp, sp, bx, dx, cx, ax;
unsigned short gs, fs, es, ds, eflags;
} regs16_t;
/**
* Execute BIOS interrupts by switching to real mode
* @param intnum The interrupt number (e.g. 0x10)
* @param regs The ASM registers
*/
extern void int32(unsigned char intnum, regs16_t *regs);
/**
* ASM segment:offset pointer
*/
struct far_ptr {
union {
uint32_t ptr;
struct {
uint16_t offset, segment;
};
};
} __attribute__ ((packed));
typedef struct far_ptr far_ptr_t;
/**
* Get offset from ASM segment:offset pointer
*/
uint16_t get_offset(const volatile void *p) {
return (uint16_t) (uintptr_t) p & 0x000F;
}
/**
* Get segment from ASM segment:offset pointer
*/
uint16_t get_segment(const volatile void *p) {
return (uint16_t) (((uintptr_t) p) >> 4);
}
/**
* Convert pointer to far_ptr
* @param __ptr The ASM segment:offset pointer
* @return The new far pointer
*/
far_ptr_t FAR_PTR(void *__ptr) {
far_ptr_t __fptr;
__fptr.offset = get_offset(__ptr);
__fptr.segment = get_segment(__ptr);
return __fptr;
}
/**
* Get pointer from ASM segment:offset far pointer
* @param fptr The ASM far pointer
* @return The normalized pointer
*/
void *get_ptr(far_ptr_t fptr) {
return (void *) (unsigned long) ((fptr.segment << 4) + fptr.offset);
}
/**
* Display a warning message
* TODO: Add line number and file name
* @param msg The warning cause/reason
*/
void warn(char *msg) {
asm volatile ("cli");
terminal_set_color(6);
terminal_write_line("WARNING");
terminal_write_string(msg);
terminal_set_color(7);
}
/**
* Halt the entire system and display a message
* TODO: Add line number and file name
* @param msg The error cause/reason
*/
void panic(char *msg) {
asm volatile ("cli");
terminal_set_color(4);
terminal_write_line("PANIC");
terminal_write_string(msg);
loop:
asm volatile ("hlt");
goto loop;
}
/**
* Assert that a value is non-zero, else panic
* TODO: Add line number and file name
* @param x The value
*/
void assert(int x) {
if (x == 0) {
panic("Assertion failed");
}
}
#endif
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