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65 lines
1.7 KiB
C
65 lines
1.7 KiB
C
/**
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*****************************************************************************
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**
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** File : sysmem.c
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**
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** Author : Ac6
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**
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** Abstract : System Workbench Minimal System Memory calls file
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**
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** For more information about which c-functions
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** need which of these lowlevel functions
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** please consult the Newlib libc-manual
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**
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** Environment : System Workbench for MCU
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**
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** Distribution: The file is distributed “as is,” without any warranty
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** of any kind.
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**
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** (c)Copyright System Workbench for MCU.
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** You may use this file as-is or modify it according to the needs of your
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** project. Distribution of this file (unmodified or modified) is not
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** permitted. System Workbench for MCU permit registered System Workbench(R) users the
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** rights to distribute the assembled, compiled & linked contents of this
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** file as part of an application binary file, provided that it is built
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** using the System Workbench for MCU toolchain.
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**
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*****************************************************************************
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*/
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/* Includes */
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#include <errno.h>
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#include <stdio.h>
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/* Variables */
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extern int errno;
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register char * stack_ptr asm("sp");
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/* Functions */
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/**
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_sbrk
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Increase program data space. Malloc and related functions depend on this
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**/
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caddr_t _sbrk(int incr)
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{
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extern char end asm("end");
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static char *heap_end;
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char *prev_heap_end;
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if (heap_end == 0)
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heap_end = &end;
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prev_heap_end = heap_end;
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if (heap_end + incr > stack_ptr)
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{
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errno = ENOMEM;
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return (caddr_t) -1;
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}
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heap_end += incr;
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return (caddr_t) prev_heap_end;
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}
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