38 lines
1.1 KiB
C
38 lines
1.1 KiB
C
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/* Copyright (c) 2020 C-SKY Microsystems All rights reserved.
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This copyrighted material is made available to anyone wishing to use,
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modify, copy, or redistribute it subject to the terms and conditions
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of the FreeBSD License. This program is distributed in the hope that
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it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
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including the implied warranties of MERCHANTABILITY or FITNESS FOR
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A PARTICULAR PURPOSE. A copy of this license is available at
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http://www.opensource.org/licenses.
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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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