src/utils/mod.rs


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use crate::disk::inode::INODE_SIZE;
use crate::{AyaFS, INODE_PER_BLOCK};
use std::time::{SystemTime, UNIX_EPOCH};

impl AyaFS {
    pub(crate) fn time_now() -> u32 {
        SystemTime::now()
            .duration_since(UNIX_EPOCH)
            .expect("How can current time be earlier than UNIX_EPOCH?")
            .as_secs() as u32
    }

    /// 输入 inode 编号, 返回它对应的 block number 和 block 内 offset
    pub(crate) fn locate_inode(&self, inode_index: usize) -> (usize, usize) {
        let block_number =
            inode_index / INODE_PER_BLOCK + 1 + self.inode_bitmap.length + self.data_bitmap.length;
        let block_offset = inode_index % INODE_PER_BLOCK * INODE_SIZE;
        (block_number, block_offset)
    }
}