tabs/kernel/kernel.c
2020-01-28 18:54:42 +01:00

91 lines
No EOL
2.2 KiB
C

/* Check if the compiler thinks you are targeting the wrong operating system. */
#if defined(__linux__)
#error "You are not using a cross-compiler, you will most certainly run into trouble"
#endif
/* This tutorial will only work for the 32-bit ix86 targets. */
#if !defined(__i386__)
#error "This kernel needs to be compiled with a ix86-elf compiler"
#endif
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "terminal.c"
#include "memory.c"
#include "interrupts.c"
#include "shell.c"
static inline bool are_interrupts_enabled() {
unsigned long flags;
asm volatile ( "pushf\n\t"
"pop %0"
: "=g"(flags) );
return flags & (1 << 9);
}
void kernel_main(void)
{
/* Initialize terminal interface */
terminal_initialize();
terminal_putchar('H');
terminal_putchar('e');
terminal_putchar('l');
terminal_putchar('l');
terminal_putchar('o');
terminal_setcolor(vga_entry_color(VGA_COLOR_GREEN, VGA_COLOR_BLACK));
terminal_writestring(" kernel");
terminal_setcolor(vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK));
terminal_writestring(" World!\n");
terminal_writestring("Newlines!\n");
char* memory_str = alloc(sizeof(char) * 7);
for (int i = 0; i < 6; i++) {
memory_str[i] = "Memory"[i];
}
memory_str[6] = 0;
char* management_str = alloc(sizeof(char) * 13);
for (int i = 0; i < 13; i++) {
management_str[i] = " management!\n"[i];
}
management_str[13] = 0;
terminal_writestring(memory_str);
terminal_writestring(management_str);
terminal_writestring("Mem after freeing!\n");
free(memory_str);
print_memory();
free(management_str);
print_memory();
char* memory_after_free = alloc(sizeof(char) * 12);
for (int i = 0; i < 13; i++) {
memory_after_free[i] = " Some text\n"[i];
}
memory_after_free[13] = 0;
terminal_writestring(memory_after_free);
terminal_writestring("Memory after new allocation!\n");
alloc(1000);
print_memory();
terminal_writestring("Free again\n");
free(memory_after_free);
print_memory();
terminal_writestring((are_interrupts_enabled())? "Interrupts!\n": "No interrupts :(\n");
interrupt_init();
for(;;) {
shell_step();
}
}