43 lines
1.2 KiB
C
43 lines
1.2 KiB
C
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/*
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* sbrk.c
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*
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* Copyright (c) 2018 Mentor Graphics
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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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/* Provided by the linker script. */
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extern char __heap_start[] __attribute__ ((aligned (8)));
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extern char __heap_end[] __attribute__ ((aligned (8)));
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void *
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sbrk (int nbytes)
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{
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static char *heap = __heap_start;
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char *base = heap;
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char *new_heap = heap + nbytes;
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if (nbytes < 0 || new_heap > __heap_end)
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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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