libgloss/m32r/sbrk.c

   1 #include <sys/types.h>
   2 #include <sys/stat.h>
   3 #include "syscall.h"
   4 #include "eit.h"
   5
   6 caddr_t
   7 _sbrk (int incr)
   8 {
   9   /* `_end' is defined in the linker script.
  10      We must handle it carefully as we don't want the compiler to think
  11      it lives in the small data area.  Use medium model to ensure 32 bit
  12      addressability.  */
  13   extern char _end __attribute__ ((__model__(__medium__)));
  14   static char *heap_end;
  15   char *prev_heap_end;
  16   char *sp = (char *)&sp;
  17
  18   if (heap_end == 0)
  19     {
  20       heap_end = &_end;
  21     }
  22   prev_heap_end = heap_end;
  23   if (heap_end > sp)
  24     {
  25       _write (1, "Heap and stack collision\n", 25);
  26 #if 0 /* Calling abort brings in the signal handling code.  */
  27       abort ();
  28 #else
  29       exit (1);
  30 #endif
  31     }
  32   heap_end += incr;
  33   return (caddr_t) prev_heap_end;
  34 }