* Generic AVR stuff.

cpu/avr/avr.c

@@ -0,0 +1,39 @@
+#include <avr/io.h>
+
+#include "contiki-conf.h"
+
+void
+cpu_init(void)
+{
+  asm volatile ("clr r1");	/* No longer needed. */
+}
+
+extern int __bss_end;
+
+#define STACK_EXTRA 32
+static char *cur_break = (char *)(&__bss_end + 1);
+
+/*
+ * Allocate memory from the heap. Check that we don't collide with the
+ * stack right now (some other routine might later). A watchdog might
+ * be used to check if cur_break and the stack pointer meet during
+ * runtime.
+ */
+void *
+sbrk(int incr)
+{
+  char *stack_pointer;
+
+  stack_pointer = (char *)SP;
+  stack_pointer -= STACK_EXTRA;
+  if(incr > (stack_pointer - cur_break))
+    return (void *)-1;          /* ENOMEM */
+
+  void *old_break = cur_break;
+  cur_break += incr;
+  /*
+   * If the stack was never here then [old_break .. cur_break] should
+   * be filled with zeros.
+  */
+  return old_break;
+}