From 777d5e01a34b8ebe6f1a5751b593266f93e88499 Mon Sep 17 00:00:00 2001 From: Chuyan Zhang Date: Sat, 25 Nov 2023 19:36:31 -0800 Subject: Add dir entry operations --- src/memory/inode_iter.rs | 233 ----------------------------------------------- 1 file changed, 233 deletions(-) delete mode 100644 src/memory/inode_iter.rs (limited to 'src/memory/inode_iter.rs') diff --git a/src/memory/inode_iter.rs b/src/memory/inode_iter.rs deleted file mode 100644 index d5909bc..0000000 --- a/src/memory/inode_iter.rs +++ /dev/null @@ -1,233 +0,0 @@ -use std::ffi::OsStr; -use std::os::unix::ffi::OsStrExt; -use libc::{c_int, ENOENT, ENOSPC}; -use crate::disk::block::{Block, DirectoryBlock, DirectoryEntry, DoubleIndirectBlock, IndirectBlock, TripleIndirectBlock}; -use crate::disk::inode::{Inode, DIRECT_NUMBER}; -use crate::{AyaFS, INODE_PER_BLOCK}; -use crate::memory::cached_block::CachedBlock; - -impl AyaFS { - pub(crate) fn access_block(&mut self, inode: &Inode, mut block_index_within_inode: usize) -> Option<&CachedBlock> { - // direct block - if block_index_within_inode < DIRECT_NUMBER { - let block_index = inode.direct[block_index_within_inode] as usize; - return self.get_block::(block_index); - } else { - block_index_within_inode -= DIRECT_NUMBER; - } - - // indirect block - let indirect_number = INODE_PER_BLOCK; - if block_index_within_inode < indirect_number { - return if let Some(indirect_block) = - self.get_block::(inode.single_indirect as usize) - { - let block_index = indirect_block.block.entries[block_index_within_inode] as usize; - self.get_block::(block_index) - } else { - None - }; - } else { - block_index_within_inode -= indirect_number; - } - - // double indirect block - let double_indirect_number = INODE_PER_BLOCK * INODE_PER_BLOCK; - if block_index_within_inode < double_indirect_number { - if let Some(double_indirect_block) = - self.get_block::(inode.double_indirect as usize) - { - // 取出 double indirect block - let indirect_block_index = double_indirect_block.block.indirect - [block_index_within_inode / INODE_PER_BLOCK] - as usize; - // 要找的 entry 在 double indirect block 中的第几个 indirect block - if let Some(indirect_block) = self.get_block::(indirect_block_index) - { - let block_index = indirect_block.block.entries - [block_index_within_inode % INODE_PER_BLOCK] - as usize; - // 拿到 DirectoryBlock 的 index - return self.get_block::(block_index); - } - } - return None; - } else { - block_index_within_inode -= double_indirect_number; - } - - // triple indirect block - if let Some(triple_indirect_block) = - self.get_block::(inode.triple_indirect as usize) - { - // 取出 triple indirect block - let double_indirect_block_index = triple_indirect_block.block.double_indirect - [block_index_within_inode / (INODE_PER_BLOCK * INODE_PER_BLOCK)] - as usize; - // 要找的 entry 在 triple indirect block 中的第几个 double indirect block - if let Some(double_indirect_block) = - self.get_block::(double_indirect_block_index) - { - // 取出 double indirect block - let indirect_block_index = double_indirect_block.block.indirect - [block_index_within_inode % (INODE_PER_BLOCK * INODE_PER_BLOCK) - / INODE_PER_BLOCK] as usize; - // 要找的 entry 在 double indirect block 中的第几个 indirect block - if let Some(indirect_block) = self.get_block::(indirect_block_index) - { - let block_index = indirect_block.block.entries - [block_index_within_inode % INODE_PER_BLOCK] - as usize; - // DirectoryBlock 的 index - return self.get_block::(block_index); - } - } - } - - None - } - - pub(crate) fn add_direntry( - &mut self, - parent_inode: &mut Inode, - child_inode_index: u32, - child_inode_name: &OsStr, - child_inode: &Inode, - ) -> Result { - let entry_index = parent_inode.size; - let block_index_within_inode = (entry_index / 15) as usize; - let entry_index_within_block = (entry_index % 15) as usize; - - // TODO 如果 block 内 offset 是 0 （或者访问到 block_index_within_inode 无效?）则为 Inode 分配新的 block - - // TODO 把新的 entry 写到对应位置 - - Err(ENOSPC) - } - pub(crate) fn get_direntry( - &mut self, - inode: &Inode, - entry_index: u32 - ) -> Option { - let block_index_within_inode = (entry_index / 15) as usize; - let entry_index_within_block = (entry_index % 15) as usize; - - self.access_block::(inode, block_index_within_inode) - .map(|directory_block| { - directory_block.block.entries[entry_index_within_block].clone() - }) - } - - // pub(crate) fn get_direntry( - // &mut self, - // inode: &Inode, - // entry_index: u32, - // ) -> Option { - // // 每个 DirectoryBlock 里有 15 个 entry, 先确定 block 再确定 offset - // let mut block_index_within_inode = (entry_index / 15) as usize; - // let entry_index_within_block = (entry_index % 15) as usize; - // - // // direct block - // if block_index_within_inode < DIRECT_NUMBER { - // let block_index = inode.direct[block_index_within_inode] as usize; - // return self - // .get_block::(block_index) - // .map(|inode_block| inode_block.block.entries[entry_index_within_block].clone()); - // } else { - // block_index_within_inode -= DIRECT_NUMBER; - // } - // - // // indirect block - // let indirect_number = INODE_PER_BLOCK; - // if block_index_within_inode < indirect_number { - // return if let Some(indirect_block) = - // self.get_block::(inode.single_indirect as usize) - // { - // let block_index = indirect_block.block.entries[block_index_within_inode] as usize; - // self.get_block::(block_index) - // .map(|inode_block| inode_block.block.entries[entry_index_within_block].clone()) - // } else { - // None - // }; - // } else { - // block_index_within_inode -= indirect_number; - // } - // - // // double indirect block - // let double_indirect_number = INODE_PER_BLOCK * INODE_PER_BLOCK; - // if block_index_within_inode < double_indirect_number { - // if let Some(double_indirect_block) = - // self.get_block::(inode.double_indirect as usize) - // { - // // 取出 double indirect block - // let indirect_block_index = double_indirect_block.block.indirect - // [block_index_within_inode / INODE_PER_BLOCK] - // as usize; - // // 要找的 entry 在 double indirect block 中的第几个 indirect block - // if let Some(indirect_block) = self.get_block::(indirect_block_index) - // { - // let block_index = indirect_block.block.entries - // [block_index_within_inode % INODE_PER_BLOCK] - // as usize; - // // 拿到 DirectoryBlock 的 index - // return self - // .get_block::(block_index) - // .map(|inode_block| { - // inode_block.block.entries[entry_index_within_block].clone() - // }); - // } - // } - // return None; - // } else { - // block_index_within_inode -= double_indirect_number; - // } - // - // // triple indirect block - // if let Some(triple_indirect_block) = - // self.get_block::(inode.triple_indirect as usize) - // { - // // 取出 triple indirect block - // let double_indirect_block_index = triple_indirect_block.block.double_indirect - // [block_index_within_inode / (INODE_PER_BLOCK * INODE_PER_BLOCK)] - // as usize; - // // 要找的 entry 在 triple indirect block 中的第几个 double indirect block - // if let Some(double_indirect_block) = - // self.get_block::(double_indirect_block_index) - // { - // // 取出 double indirect block - // let indirect_block_index = double_indirect_block.block.indirect - // [block_index_within_inode % (INODE_PER_BLOCK * INODE_PER_BLOCK) - // / INODE_PER_BLOCK] as usize; - // // 要找的 entry 在 double indirect block 中的第几个 indirect block - // if let Some(indirect_block) = self.get_block::(indirect_block_index) - // { - // let block_index = indirect_block.block.entries - // [block_index_within_inode % INODE_PER_BLOCK] - // as usize; - // // DirectoryBlock 的 index - // return self - // .get_block::(block_index) - // .map(|inode_block| { - // inode_block.block.entries[entry_index_within_block].clone() - // }); - // } - // } - // } - // None - // } - - // TODO 实现一个带 cache 的版本 - pub fn lookup_name(&mut self, parent_inode: &Inode, name: &OsStr) -> Result<(u32, Inode), c_int> { - let mut entry_index = 0; - while entry_index < parent_inode.size { - if let Some(entry) = self.get_direntry(parent_inode, entry_index) { - if entry.name() == name { - let inode = self.get_inode(entry.inode as usize).unwrap().clone(); - return Ok((entry.inode, inode)) - } - } - entry_index += 1; - } - Err(ENOENT) - } -} -- cgit v1.2.3-70-g09d2