rt-thread-official/components/libc/posix/io/mman/mman.c

68 lines
1.1 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2017/11/30 Bernard The first version.
*/
#include <stdint.h>
#include <stdio.h>
#include <rtthread.h>
#include <dfs_posix.h>
#include "sys/mman.h"
void *mmap(void *addr, size_t length, int prot, int flags,
int fd, off_t offset)
{
uint8_t *mem;
if (addr)
{
mem = addr;
}
else mem = (uint8_t *)malloc(length);
if (mem)
{
off_t cur;
size_t read_bytes;
cur = lseek(fd, 0, SEEK_SET);
lseek(fd, offset, SEEK_SET);
read_bytes = read(fd, mem, length);
if (read_bytes != length)
{
if (addr == RT_NULL)
{
/* read failed */
free(mem);
mem = RT_NULL;
}
}
lseek(fd, cur, SEEK_SET);
return mem;
}
errno = ENOMEM;
return MAP_FAILED;
}
int munmap(void *addr, size_t length)
{
if (addr)
{
free(addr);
return 0;
}
return -1;
}