facebook/sapling
1
1
Fork 0
mirror of https://github.com/facebook/sapling.git synced 2024-10-07 07:17:55 +03:00
Code Issues Projects Releases Wiki Activity

indexedlog: recover from partially created LogRotate

Browse Source 
Summary:
In some rare cases, it's possible that the "latest" file is created, but the
matching indexedlog isn't. Let's nicely recover from this by creating the
indexedlog in this case.

Reviewed By: kulshrax

Differential Revision: D16554090

fbshipit-source-id: 6b68d7806662b511917655a71c3a3c15ad6e1f64
This commit is contained in:
Xavier Deguillard 2019-07-30 10:09:20 -07:00 committed by Facebook Github Bot
parent bd75a8e099
commit e30a0b41f3
1 changed files with 44 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
lib/indexedlog/src/rotate.rs
View File

@ -118,20 +118,27 @@ impl OpenOptions {
pub fn open(self, dir: impl AsRef<Path>) -> Fallible<RotateLog> {
let dir = dir.as_ref();
let latest_path = dir.join(LATEST_FILE);
let (latest, logs) = if !self.log_open_options.create || latest_path.exists() {
let latest = read_latest(dir)?;
(latest, read_logs(dir, &self, latest)?)
} else {
fs::create_dir_all(dir)?;
let mut lock_file = open_dir(dir)?;
let _lock = ScopedFileLock::new(&mut lock_file, true)?;
if latest_path.exists() {
// Two creates raced and the other one has created basic files.
let latest = read_latest(dir)?;
(latest, read_logs(dir, &self, latest)?)
} else {
(0, vec![create_empty_log(Some(dir), &self, 0)?])
let latest_and_log = read_latest_and_logs(dir, &self);
let (latest, logs) = match latest_and_log {
Ok((latest, logs)) => (latest, logs),
Err(e) => {
if !self.log_open_options.create {
return Err(e);
} else {
fs::create_dir_all(dir)?;
let mut lock_file = open_dir(dir)?;
let _lock = ScopedFileLock::new(&mut lock_file, true)?;
let latest_and_log = read_latest_and_logs(dir, &self);
// two creates raced and the other one has created basic files.
if let Ok((latest, logs)) = latest_and_log {
(latest, logs)
} else {
(0, vec![create_empty_log(Some(dir), &self, 0)?])
}
}
}
};
@ -464,6 +471,11 @@ fn read_logs(dir: &Path, open_options: &OpenOptions, latest: u8) -> Fallible<Vec
}
}
fn read_latest_and_logs(dir: &Path, open_options: &OpenOptions) -> Fallible<(u8, Vec<Log>)> {
let latest = read_latest(dir)?;
Ok((latest, read_logs(dir, open_options, latest)?))
}
#[cfg(test)]
mod tests {
use super::*;
@ -777,4 +789,22 @@ mod tests {
vec![a, b]
);
}
#[test]
fn recover_from_partially_created() -> Fallible<()> {
let dir = tempdir().unwrap();
let rotate = OpenOptions::new().create(true).open(&dir)?;
drop(rotate);
for dirent in fs::read_dir(&dir)? {
let dirent = dirent?;
let path = dirent.path();
if path.is_dir() {
fs::remove_dir_all(path)?;
}
}
let _ = OpenOptions::new().create(true).open(&dir)?;
Ok(())
}
}