46 lines
1.2 KiB
C
46 lines
1.2 KiB
C
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/* sbrk.c -- allocate memory dynamically.
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*
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*
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* Copyright (C) 2015 FTDI (support@ftdichip.com)
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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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#include "glue.h"
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char *__heap_ptr = (char *)&_end;
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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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char *
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_sbrk (nbytes)
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int nbytes;
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{
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char *base;
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char *sp;
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char canary;
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if ((__heap_ptr + nbytes) < (&canary - 2000))
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{
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base = __heap_ptr;
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__heap_ptr += nbytes;
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return base;
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}
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else
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{
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errno = ENOMEM;
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return ((char *)-1);
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}
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}
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