31 lines
588 B
C
31 lines
588 B
C
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#include <_ansi.h>
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include "trap.h"
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caddr_t
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_sbrk (size_t incr)
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{
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extern char __stack; /* Defined by the linker */
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extern char _end; /* Defined by the linker */
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static char *heap_end;
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char *prev_heap_end;
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char *sp = (char *)&sp;
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if (heap_end == 0)
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{
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heap_end = &_end;
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}
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prev_heap_end = heap_end;
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heap_end += incr;
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if (heap_end > sp)
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{
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_write (1, "Heap and stack collision\n", 25);
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errno = ENOMEM;
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return (caddr_t)-1;
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}
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return (caddr_t) prev_heap_end;
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}
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