embox

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/**
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 * @file
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 *
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 * @date Dec 12, 2019
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 * @author Anton Bondarev
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 */
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#include <stddef.h>
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#include <fcntl.h>
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#include <fs/file_desc.h>
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#include <fs/inode.h>
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#include <fs/super_block.h>
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#include "fat.h"
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static size_t fat_read(struct file_desc *desc, void *buf, size_t size) {
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	size_t rezult;
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	uint32_t bytecount;
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	struct fat_file_info *fi;
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	fi = file_get_inode_data(desc);
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	fi->pointer = file_get_pos(desc);
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	rezult = fat_read_file(fi, fat_sector_buff, buf, &bytecount, size);
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	if (DFS_OK == rezult) {
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		return bytecount;
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	}
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	return 0;
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}
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static size_t fat_write(struct file_desc *desc, void *buf, size_t size) {
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	size_t rezult;
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	uint32_t bytecount;
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	struct fat_file_info *fi;
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	size_t new_sz;
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	int old_pos = file_get_pos(desc);
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	fi = file_get_inode_data(desc);
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	fi->pointer = old_pos;
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	new_sz = file_get_size(desc);
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	fi->mode = O_RDWR; /* XXX */
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	rezult = fat_write_file(fi, fat_sector_buff, (uint8_t *)buf,
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			&bytecount, size, &new_sz);
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	if (DFS_OK == rezult || DFS_EOF == rezult) {
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		if (old_pos + bytecount > file_get_size(desc)) {
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			file_set_size(desc, old_pos + bytecount);
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			fi->filelen = old_pos + bytecount;
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		}
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		return bytecount;
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	}
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	return 0;
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}
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struct file_operations fat_fops = {
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	.read = fat_read,
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	.write = fat_write,
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};
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