##// END OF EJS Templates
upgrade: implement partial upgrade for upgrading persistent-nodemap...
upgrade: implement partial upgrade for upgrading persistent-nodemap Upgrading repositories to use persistent nodemap should be fast and easy as it requires only two things: 1) Updating the requirements 2) Writing a persistent-nodemap on disk For both of the steps above, we don't need to edit existing revlogs. This patch makes upgrade only do the above mentioned two steps if we are only upgarding to use persistent-nodemap feature. Since `nodemap.persist_nodemap()` assumes that there exists a nodemap file for the given revlog if we are trying to call it, this patch adds `force` argument to create a file if does not exist which is true in our upgrade case. The test changes demonstrate that we no longer write nodemap files for manifest after upgrade which I think is desirable. Differential Revision: https://phab.mercurial-scm.org/D9936

File last commit:

r46365:ae2873e9 default
r47199:98e39f04 default
Show More
node.rs
398 lines | 13.1 KiB | application/rls-services+xml | RustLexer
// node.rs
//
// Copyright 2020, Raphaël Gomès <rgomes@octobus.net>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.
use super::iter::Iter;
use crate::utils::hg_path::HgPathBuf;
use crate::{DirstateEntry, EntryState, FastHashMap};
/// Represents a filesystem directory in the dirstate tree
#[derive(Debug, Default, Clone, PartialEq)]
pub struct Directory {
/// Contains the old file information if it existed between changesets.
/// Happens if a file `foo` is marked as removed, removed from the
/// filesystem then a directory `foo` is created and at least one of its
/// descendents is added to Mercurial.
pub(super) was_file: Option<Box<File>>,
pub(super) children: FastHashMap<Vec<u8>, Node>,
}
/// Represents a filesystem file (or symlink) in the dirstate tree
#[derive(Debug, Clone, PartialEq)]
pub struct File {
/// Contains the old structure if it existed between changesets.
/// Happens all descendents of `foo` marked as removed and removed from
/// the filesystem, then a file `foo` is created and added to Mercurial.
pub(super) was_directory: Option<Box<Directory>>,
pub(super) entry: DirstateEntry,
}
#[derive(Debug, Clone, PartialEq)]
pub enum NodeKind {
Directory(Directory),
File(File),
}
#[derive(Debug, Default, Clone, PartialEq)]
pub struct Node {
pub kind: NodeKind,
}
impl Default for NodeKind {
fn default() -> Self {
NodeKind::Directory(Default::default())
}
}
impl Node {
pub fn insert(
&mut self,
path: &[u8],
new_entry: DirstateEntry,
) -> InsertResult {
let mut split = path.splitn(2, |&c| c == b'/');
let head = split.next().unwrap_or(b"");
let tail = split.next().unwrap_or(b"");
// Are we're modifying the current file ? Is the the end of the path ?
let is_current_file = tail.is_empty() && head.is_empty();
// Potentially Replace the current file with a directory if it's marked
// as `Removed`
if !is_current_file {
if let NodeKind::File(file) = &mut self.kind {
if file.entry.state == EntryState::Removed {
self.kind = NodeKind::Directory(Directory {
was_file: Some(Box::from(file.clone())),
children: Default::default(),
})
}
}
}
match &mut self.kind {
NodeKind::Directory(directory) => {
Node::insert_in_directory(directory, new_entry, head, tail)
}
NodeKind::File(file) => {
if is_current_file {
let new = Self {
kind: NodeKind::File(File {
entry: new_entry,
..file.clone()
}),
};
InsertResult {
did_insert: false,
old_entry: Some(std::mem::replace(self, new)),
}
} else {
match file.entry.state {
EntryState::Removed => {
unreachable!("Removed file turning into a directory was dealt with earlier")
}
_ => {
Node::insert_in_file(
file, new_entry, head, tail,
)
}
}
}
}
}
}
/// The current file still exists and is not marked as `Removed`.
/// Insert the entry in its `was_directory`.
fn insert_in_file(
file: &mut File,
new_entry: DirstateEntry,
head: &[u8],
tail: &[u8],
) -> InsertResult {
if let Some(d) = &mut file.was_directory {
Node::insert_in_directory(d, new_entry, head, tail)
} else {
let mut dir = Directory {
was_file: None,
children: FastHashMap::default(),
};
let res =
Node::insert_in_directory(&mut dir, new_entry, head, tail);
file.was_directory = Some(Box::new(dir));
res
}
}
/// Insert an entry in the subtree of `directory`
fn insert_in_directory(
directory: &mut Directory,
new_entry: DirstateEntry,
head: &[u8],
tail: &[u8],
) -> InsertResult {
let mut res = InsertResult::default();
if let Some(node) = directory.children.get_mut(head) {
// Node exists
match &mut node.kind {
NodeKind::Directory(subdir) => {
if tail.is_empty() {
let becomes_file = Self {
kind: NodeKind::File(File {
was_directory: Some(Box::from(subdir.clone())),
entry: new_entry,
}),
};
let old_entry = directory
.children
.insert(head.to_owned(), becomes_file);
return InsertResult {
did_insert: true,
old_entry,
};
} else {
res = node.insert(tail, new_entry);
}
}
NodeKind::File(_) => {
res = node.insert(tail, new_entry);
}
}
} else if tail.is_empty() {
// File does not already exist
directory.children.insert(
head.to_owned(),
Self {
kind: NodeKind::File(File {
was_directory: None,
entry: new_entry,
}),
},
);
res.did_insert = true;
} else {
// Directory does not already exist
let mut nested = Self {
kind: NodeKind::Directory(Directory {
was_file: None,
children: Default::default(),
}),
};
res = nested.insert(tail, new_entry);
directory.children.insert(head.to_owned(), nested);
}
res
}
/// Removes an entry from the tree, returns a `RemoveResult`.
pub fn remove(&mut self, path: &[u8]) -> RemoveResult {
let empty_result = RemoveResult::default();
if path.is_empty() {
return empty_result;
}
let mut split = path.splitn(2, |&c| c == b'/');
let head = split.next();
let tail = split.next().unwrap_or(b"");
let head = match head {
None => {
return empty_result;
}
Some(h) => h,
};
if head == path {
match &mut self.kind {
NodeKind::Directory(d) => {
return Node::remove_from_directory(head, d);
}
NodeKind::File(f) => {
if let Some(d) = &mut f.was_directory {
let RemoveResult { old_entry, .. } =
Node::remove_from_directory(head, d);
return RemoveResult {
cleanup: false,
old_entry,
};
}
}
}
empty_result
} else {
// Look into the dirs
match &mut self.kind {
NodeKind::Directory(d) => {
if let Some(child) = d.children.get_mut(head) {
let mut res = child.remove(tail);
if res.cleanup {
d.children.remove(head);
}
res.cleanup =
d.children.is_empty() && d.was_file.is_none();
res
} else {
empty_result
}
}
NodeKind::File(f) => {
if let Some(d) = &mut f.was_directory {
if let Some(child) = d.children.get_mut(head) {
let RemoveResult { cleanup, old_entry } =
child.remove(tail);
if cleanup {
d.children.remove(head);
}
if d.children.is_empty() && d.was_file.is_none() {
f.was_directory = None;
}
return RemoveResult {
cleanup: false,
old_entry,
};
}
}
empty_result
}
}
}
}
fn remove_from_directory(head: &[u8], d: &mut Directory) -> RemoveResult {
if let Some(node) = d.children.get_mut(head) {
return match &mut node.kind {
NodeKind::Directory(d) => {
if let Some(f) = &mut d.was_file {
let entry = f.entry;
d.was_file = None;
RemoveResult {
cleanup: false,
old_entry: Some(entry),
}
} else {
RemoveResult::default()
}
}
NodeKind::File(f) => {
let entry = f.entry;
let mut cleanup = false;
match &f.was_directory {
None => {
if d.children.len() == 1 {
cleanup = true;
}
d.children.remove(head);
}
Some(dir) => {
node.kind = NodeKind::Directory(*dir.clone());
}
}
RemoveResult {
cleanup,
old_entry: Some(entry),
}
}
};
}
RemoveResult::default()
}
pub fn get(&self, path: &[u8]) -> Option<&Node> {
if path.is_empty() {
return Some(&self);
}
let mut split = path.splitn(2, |&c| c == b'/');
let head = split.next();
let tail = split.next().unwrap_or(b"");
let head = match head {
None => {
return Some(&self);
}
Some(h) => h,
};
match &self.kind {
NodeKind::Directory(d) => {
if let Some(child) = d.children.get(head) {
return child.get(tail);
}
}
NodeKind::File(f) => {
if let Some(d) = &f.was_directory {
if let Some(child) = d.children.get(head) {
return child.get(tail);
}
}
}
}
None
}
pub fn get_mut(&mut self, path: &[u8]) -> Option<&mut NodeKind> {
if path.is_empty() {
return Some(&mut self.kind);
}
let mut split = path.splitn(2, |&c| c == b'/');
let head = split.next();
let tail = split.next().unwrap_or(b"");
let head = match head {
None => {
return Some(&mut self.kind);
}
Some(h) => h,
};
match &mut self.kind {
NodeKind::Directory(d) => {
if let Some(child) = d.children.get_mut(head) {
return child.get_mut(tail);
}
}
NodeKind::File(f) => {
if let Some(d) = &mut f.was_directory {
if let Some(child) = d.children.get_mut(head) {
return child.get_mut(tail);
}
}
}
}
None
}
pub fn iter(&self) -> Iter {
Iter::new(self)
}
}
/// Information returned to the caller of an `insert` operation for integrity.
#[derive(Debug, Default)]
pub struct InsertResult {
/// Whether the insertion resulted in an actual insertion and not an
/// update
pub(super) did_insert: bool,
/// The entry that was replaced, if it exists
pub(super) old_entry: Option<Node>,
}
/// Information returned to the caller of a `remove` operation integrity.
#[derive(Debug, Default)]
pub struct RemoveResult {
/// If the caller needs to remove the current node
pub(super) cleanup: bool,
/// The entry that was replaced, if it exists
pub(super) old_entry: Option<DirstateEntry>,
}
impl<'a> IntoIterator for &'a Node {
type Item = (HgPathBuf, DirstateEntry);
type IntoIter = Iter<'a>;
fn into_iter(self) -> Self::IntoIter {
self.iter()
}
}