newoswan/source/file_access.c

83 lines
1.8 KiB
C

/*******************************************************************************
* NewOswan
* file_access.c: File manipulation functions
*
* Created by Manoël Trapier on 27/06/2022.
* Copyright (c) 2014-2022 986-Studio. All rights reserved.
*
* This file is OS specific and this need to be changed at some point.
*
******************************************************************************/
#include <stdint.h>
#include <stdbool.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <file_access.h>
#include <log.h>
char *load_file(char *filename, bool readOnly)
{
int fd;
char *ret_ptr;
struct stat FileStat;
int flags = readOnly?MAP_ANONYMOUS:MAP_SHARED;
fd = open(filename, O_RDWR);
fstat(fd, &FileStat);
Log(TLOG_DEBUG, "memory", "Trying to load %s, size = %lu...", filename, (unsigned long)FileStat.st_size);
ret_ptr = (char *)mmap(NULL, FileStat.st_size, PROT_READ | PROT_WRITE, flags, fd, 0);
close(fd);
if (ret_ptr == MAP_FAILED)
{
ret_ptr = NULL;
}
return ret_ptr;
}
char *create_file(char *filename, uint32_t size)
{
int fd;
uint32_t i;
char *ret_ptr;
char buf[] = {0};
Log(TLOG_DEBUG, "memory", "Trying to create %s, size = %u...\n", filename, size);
fd = open(filename, O_CREAT | S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH | O_TRUNC, 0644);
fchmod(fd, 0644);
close(fd);
sync();
fd = open(filename, O_RDWR);
for (i = 0 ; i < size ; i++)
{
write(fd, buf, 1);
}
close(fd);
sync();
fd = open(filename, O_RDWR);
ret_ptr = (char *)mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
close(fd);
if (ret_ptr == MAP_FAILED)
{
ret_ptr = NULL;
}
return ret_ptr;
}