diff options
Diffstat (limited to 'tvix/store/src/fs/inode_tracker.rs')
-rw-r--r-- | tvix/store/src/fs/inode_tracker.rs | 207 |
1 files changed, 0 insertions, 207 deletions
diff --git a/tvix/store/src/fs/inode_tracker.rs b/tvix/store/src/fs/inode_tracker.rs deleted file mode 100644 index 3cabbbd247b5..000000000000 --- a/tvix/store/src/fs/inode_tracker.rs +++ /dev/null @@ -1,207 +0,0 @@ -use std::{collections::HashMap, sync::Arc}; - -use super::inodes::{DirectoryInodeData, InodeData}; -use tvix_castore::B3Digest; - -/// InodeTracker keeps track of inodes, stores data being these inodes and deals -/// with inode allocation. -pub struct InodeTracker { - data: HashMap<u64, Arc<InodeData>>, - - // lookup table for blobs by their B3Digest - blob_digest_to_inode: HashMap<B3Digest, u64>, - - // lookup table for symlinks by their target - symlink_target_to_inode: HashMap<bytes::Bytes, u64>, - - // lookup table for directories by their B3Digest. - // Note the corresponding directory may not be present in data yet. - directory_digest_to_inode: HashMap<B3Digest, u64>, - - // the next inode to allocate - next_inode: u64, -} - -impl Default for InodeTracker { - fn default() -> Self { - Self { - data: Default::default(), - - blob_digest_to_inode: Default::default(), - symlink_target_to_inode: Default::default(), - directory_digest_to_inode: Default::default(), - - next_inode: 2, - } - } -} - -impl InodeTracker { - // Retrieves data for a given inode, if it exists. - pub fn get(&self, ino: u64) -> Option<Arc<InodeData>> { - self.data.get(&ino).cloned() - } - - // Replaces data for a given inode. - // Panics if the inode doesn't already exist. - pub fn replace(&mut self, ino: u64, data: Arc<InodeData>) { - if self.data.insert(ino, data).is_none() { - panic!("replace called on unknown inode"); - } - } - - // Stores data and returns the inode for it. - // In case an inode has already been allocated for the same data, that inode - // is returned, otherwise a new one is allocated. - // In case data is a [InodeData::Directory], inodes for all items are looked - // up - pub fn put(&mut self, data: InodeData) -> u64 { - match data { - InodeData::Regular(ref digest, _, _) => { - match self.blob_digest_to_inode.get(digest) { - Some(found_ino) => { - // We already have it, return the inode. - *found_ino - } - None => self.insert_and_increment(data), - } - } - InodeData::Symlink(ref target) => { - match self.symlink_target_to_inode.get(target) { - Some(found_ino) => { - // We already have it, return the inode. - *found_ino - } - None => self.insert_and_increment(data), - } - } - InodeData::Directory(DirectoryInodeData::Sparse(ref digest, _size)) => { - // check the lookup table if the B3Digest is known. - match self.directory_digest_to_inode.get(digest) { - Some(found_ino) => { - // We already have it, return the inode. - *found_ino - } - None => { - // insert and return the inode - self.insert_and_increment(data) - } - } - } - // Inserting [DirectoryInodeData::Populated] doesn't normally happen, - // only via [replace]. - InodeData::Directory(DirectoryInodeData::Populated(..)) => { - unreachable!("should never be called with DirectoryInodeData::Populated") - } - } - } - - // Inserts the data and returns the inode it was stored at, while - // incrementing next_inode. - fn insert_and_increment(&mut self, data: InodeData) -> u64 { - let ino = self.next_inode; - // insert into lookup tables - match data { - InodeData::Regular(ref digest, _, _) => { - self.blob_digest_to_inode.insert(digest.clone(), ino); - } - InodeData::Symlink(ref target) => { - self.symlink_target_to_inode.insert(target.clone(), ino); - } - InodeData::Directory(DirectoryInodeData::Sparse(ref digest, _size)) => { - self.directory_digest_to_inode.insert(digest.clone(), ino); - } - // This is currently not used outside test fixtures. - // Usually a [DirectoryInodeData::Sparse] is inserted and later - // "upgraded" with more data. - // However, as a future optimization, a lookup for a PathInfo could trigger a - // [DirectoryService::get_recursive()] request that "forks into - // background" and prepopulates all Directories in a closure. - InodeData::Directory(DirectoryInodeData::Populated(ref digest, _)) => { - self.directory_digest_to_inode.insert(digest.clone(), ino); - } - } - // Insert data - self.data.insert(ino, Arc::new(data)); - - // increment inode counter and return old inode. - self.next_inode += 1; - ino - } -} - -#[cfg(test)] -mod tests { - use crate::tests::fixtures; - - use super::InodeData; - use super::InodeTracker; - - /// Getting something non-existent should be none - #[test] - fn get_nonexistent() { - let inode_tracker = InodeTracker::default(); - assert!(inode_tracker.get(1).is_none()); - } - - /// Put of a regular file should allocate a uid, which should be the same when inserting again. - #[test] - fn put_regular() { - let mut inode_tracker = InodeTracker::default(); - let f = InodeData::Regular( - fixtures::BLOB_A_DIGEST.clone(), - fixtures::BLOB_A.len() as u64, - false, - ); - - // put it in - let ino = inode_tracker.put(f.clone()); - - // a get should return the right data - let data = inode_tracker.get(ino).expect("must be some"); - match *data { - InodeData::Regular(ref digest, _, _) => { - assert_eq!(&fixtures::BLOB_A_DIGEST.clone(), digest); - } - InodeData::Symlink(_) | InodeData::Directory(..) => panic!("wrong type"), - } - - // another put should return the same ino - assert_eq!(ino, inode_tracker.put(f)); - - // inserting another file should return a different ino - assert_ne!( - ino, - inode_tracker.put(InodeData::Regular( - fixtures::BLOB_B_DIGEST.clone(), - fixtures::BLOB_B.len() as u64, - false, - )) - ); - } - - // Put of a symlink should allocate a uid, which should be the same when inserting again - #[test] - fn put_symlink() { - let mut inode_tracker = InodeTracker::default(); - let f = InodeData::Symlink("target".into()); - - // put it in - let ino = inode_tracker.put(f.clone()); - - // a get should return the right data - let data = inode_tracker.get(ino).expect("must be some"); - match *data { - InodeData::Symlink(ref target) => { - assert_eq!(b"target".to_vec(), *target); - } - InodeData::Regular(..) | InodeData::Directory(..) => panic!("wrong type"), - } - - // another put should return the same ino - assert_eq!(ino, inode_tracker.put(f)); - - // inserting another file should return a different ino - assert_ne!(ino, inode_tracker.put(InodeData::Symlink("target2".into()))); - } -} |