35 lines
		
	
	
		
			795 B
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			795 B
		
	
	
	
		
			C
		
	
	
	
#include <sys/types.h>
 | 
						|
#include <sys/stat.h>
 | 
						|
#include "syscall.h"
 | 
						|
#include "eit.h"
 | 
						|
 | 
						|
caddr_t
 | 
						|
_sbrk (int incr)
 | 
						|
{
 | 
						|
  /* `_end' is defined in the linker script.
 | 
						|
     We must handle it carefully as we don't want the compiler to think
 | 
						|
     it lives in the small data area.  Use medium model to ensure 32 bit
 | 
						|
     addressability.  */
 | 
						|
  extern char _end __attribute__ ((__model__(__medium__)));
 | 
						|
  static char *heap_end;
 | 
						|
  char *prev_heap_end;
 | 
						|
  char *sp = (char *)&sp;
 | 
						|
 | 
						|
  if (heap_end == 0)
 | 
						|
    {
 | 
						|
      heap_end = &_end;
 | 
						|
    }
 | 
						|
  prev_heap_end = heap_end;
 | 
						|
  if (heap_end > sp)
 | 
						|
    {
 | 
						|
      _write (1, "Heap and stack collision\n", 25);
 | 
						|
#if 0 /* Calling abort brings in the signal handling code.  */
 | 
						|
      abort ();
 | 
						|
#else
 | 
						|
      exit (1);
 | 
						|
#endif
 | 
						|
    }
 | 
						|
  heap_end += incr;
 | 
						|
  return (caddr_t) prev_heap_end;
 | 
						|
}
 |