PL0_test.c


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#include "PL0_utils.h"

// entry point - must remain the only function in the file!
void PL0_main(void)
{
  // If loading program to userspace and handling of svc are
  // implemented correctly, this shall get printed
  puts("Hello userspace!");
  
  // if we're indeed in PL0, we should trigger the abort handler now,
  // when trying to access memory we're not allowed to
  puts("Attempting to meddle with kernel memory from userspace :d");
  char first_kernel_byte[2];

  first_kernel_byte[0] = *(char*) 0x0;
  first_kernel_byte[1] = '\0';

  puts(first_kernel_byte);
    
  while (1)
    {
      char c = getchar();
      
      if (c == '\r')
	putchar('\n');

      putchar(c);
    }
}