30 lines
568 B
C
30 lines
568 B
C
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#include <_ansi.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include "sys/syscall.h"
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caddr_t
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_sbrk (int incr)
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{
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extern char heap_start[]; /* Defined by the linker script. */
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static char * heap_end = NULL;
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char * prev_heap_end;
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char * sp = (char *) & sp;
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if (heap_end == NULL)
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heap_end = heap_start;
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prev_heap_end = heap_end;
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if (heap_end + incr > sp)
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{
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#define MESSAGE "Heap and stack collision\n"
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_write (1, MESSAGE, sizeof MESSAGE);
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abort ();
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}
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heap_end += incr;
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return (caddr_t) prev_heap_end;
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}
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