newlib/libc/sys/sysmec/sbrk.c

   1 #include <_ansi.h>
   2 #include <sys/types.h>
   3 #include <sys/stat.h>
   4 #include "sys/syscall.h"
   5
   6 int errno;
   7
   8 int __trap0 ();
   9
  10 #define TRAP0(f, p1, p2, p3) __trap0(f, (p1), (p2), (p3))
  11
  12 caddr_t
  13 _sbrk (size_t incr)
  14 {
  15   extern char end;              /* Defined by the linker */
  16   static char *heap_end;
  17   char *prev_heap_end;
  18 #if 0
  19   char *sp = (char *)stack_ptr;
  20 #else
  21   char *sp = (char *)&sp;
  22 #endif
  23
  24   if (heap_end == 0)
  25     {
  26       heap_end = &end;
  27     }
  28   prev_heap_end = heap_end;
  29   if (heap_end + incr > sp)
  30     {
  31       _write (1, "Heap and stack collision\n", 25);
  32       abort ();
  33     }
  34   heap_end += incr;
  35   return (caddr_t) prev_heap_end;
  36 }