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;
 | |
| }
 |