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