Trait avrox_storage::fs::FileSystemRead

pub trait FileSystemRead {
    type FID: Copy;

    const BLOCK_DATA_SIZE: usize;

    // Required methods
    fn read_from_location(
        &self,
        file: Self::FID,
        block: BlockNumber,
        offset: usize,
        buf: &mut [u8]
    ) -> FileSystemResult<(usize, (BlockNumber, usize))>;
    fn check_exists(&self, file: Self::FID) -> bool;
    fn get_file_size(&self, file: Self::FID) -> FileSystemResult<FileAddr>;
    fn get_free_space(&self) -> FileSystemResult<u64>;
    fn block_and_offset_for_file_location(
        &self,
        file: Self::FID,
        addr: FileAddr
    ) -> FileSystemResult<(BlockNumber, usize)>;
    fn get_next_file_in_directory(
        &self,
        parent: Option<Self::FID>,
        previous: Option<Self::FID>
    ) -> Option<Self::FID>;
}

Required Associated Types

type FID: Copy

Required Associated Constants

const BLOCK_DATA_SIZE: usize

Required Methods

fn read_from_location( &self, file: Self::FID, block: BlockNumber, offset: usize, buf: &mut [u8] ) -> FileSystemResult<(usize, (BlockNumber, usize))>

Read from the given file location into the buffer. The number of bytes read, and the new location at the end of the read, are returned.

This method does not guarantee to read all the bytes requested, you must pay attention to the number of bytes read returned.

fn check_exists(&self, file: Self::FID) -> bool

Check if the given file exists

fn get_file_size(&self, file: Self::FID) -> FileSystemResult<FileAddr>

Return the size of the given file

fn get_free_space(&self) -> FileSystemResult<u64>

Return the approximate amount of free space, in bytes

fn block_and_offset_for_file_location( &self, file: Self::FID, addr: FileAddr ) -> FileSystemResult<(BlockNumber, usize)>

Return the (block,offset) address for the given absolute file location (bytes since start of file).

fn get_next_file_in_directory( &self, parent: Option<Self::FID>, previous: Option<Self::FID> ) -> Option<Self::FID>

Return the filesystem entry following the given filesystem entry in the directory listing

Object Safety

This trait is not object safe.

Implementors

impl<SD> FileSystemRead for SnafusFileSystem<SD>

where SD: Storage + RandomRead,

type FID = FileUid

const BLOCK_DATA_SIZE: usize = 250usize