82 lines
1.8 KiB
C
82 lines
1.8 KiB
C
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/*
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* File : posix_mmap.c
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* This file is part of RT-Thread RTOS
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* COPYRIGHT (C) 2017, RT-Thread Development Team
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Change Logs:
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* Date Author Notes
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* 2017/11/30 Bernard The first version.
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*/
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#include <stdint.h>
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#include <stdio.h>
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#include <rtthread.h>
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#include <dfs_posix.h>
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#include <sys/mman.h>
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void *mmap(void *addr, size_t length, int prot, int flags,
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int fd, off_t offset)
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{
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uint8_t *mem;
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if (addr)
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{
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mem = addr;
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}
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else mem = (uint8_t *)malloc(length);
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if (mem)
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{
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off_t cur;
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size_t read_bytes;
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cur = lseek(fd, 0, SEEK_SET);
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lseek(fd, offset, SEEK_SET);
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read_bytes = read(fd, addr, length);
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if (read_bytes != length)
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{
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if (addr == RT_NULL)
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{
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/* read failed */
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free(mem);
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mem = RT_NULL;
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}
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}
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lseek(fd, cur, SEEK_SET);
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return mem;
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}
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errno = ENOMEM;
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return MAP_FAILED;
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}
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int munmap(void *addr, size_t length)
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{
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if (addr)
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{
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free(addr);
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return 0;
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}
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return -1;
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}
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