51 lines
1.4 KiB
C
51 lines
1.4 KiB
C
/*
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* cf-sbrk.c --
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*
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* Copyright (c) 2006 CodeSourcery Inc
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*
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* The authors hereby grant permission to use, copy, modify, distribute,
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* and license this software and its documentation for any purpose, provided
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* that existing copyright notices are retained in all copies and that this
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* notice is included verbatim in any distributions. No written agreement,
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* license, or royalty fee is required for any of the authorized uses.
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* Modifications to this software may be copyrighted by their authors
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* and need not follow the licensing terms described here, provided that
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* the new terms are clearly indicated on the first page of each file where
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* they apply.
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*/
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#include <errno.h>
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/*
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* sbrk -- changes heap size size. Get nbytes more
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* RAM. We just increment a pointer in what's
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* left of memory on the board.
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*/
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extern char __end[] __attribute__ ((aligned (4)));
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/* End of heap, if non NULL. */
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extern void *__heap_limit;
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void *
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sbrk (int nbytes)
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{
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static char *heap = __end;
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char *end = __heap_limit;
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char *base = heap;
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char *new_heap = heap + nbytes;
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if (!end)
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{
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/* Use sp - 256 as the heap limit. */
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__asm__ __volatile__ ("move.l %/sp,%0" : "=r"(end));
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end -= 256;
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}
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if (nbytes < 0 || (long)(end - new_heap) < 0)
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{
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errno = ENOMEM;
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return (void *)-1;
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}
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heap = new_heap;
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return base;
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}
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