diff options
Diffstat (limited to 'src/bootstrap/bin/main.rs')
| -rw-r--r-- | src/bootstrap/bin/main.rs | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/src/bootstrap/bin/main.rs b/src/bootstrap/bin/main.rs index be69f819c..3856bb64f 100644 --- a/src/bootstrap/bin/main.rs +++ b/src/bootstrap/bin/main.rs @@ -16,12 +16,17 @@ fn main() { let mut build_lock; let _build_lock_guard; if cfg!(any(unix, windows)) { - build_lock = fd_lock::RwLock::new(t!(std::fs::File::create(config.out.join("lock")))); + let path = config.out.join("lock"); + build_lock = fd_lock::RwLock::new(t!(std::fs::File::create(&path))); _build_lock_guard = match build_lock.try_write() { Ok(lock) => lock, err => { - println!("warning: build directory locked, waiting for lock"); drop(err); + if let Some(pid) = get_lock_owner(&path) { + println!("warning: build directory locked by process {pid}, waiting for lock"); + } else { + println!("warning: build directory locked, waiting for lock"); + } t!(build_lock.write()) } }; @@ -98,3 +103,30 @@ fn check_version(config: &Config) -> Option<String> { Some(msg) } + +/// Get the PID of the process which took the write lock by +/// parsing `/proc/locks`. +#[cfg(target_os = "linux")] +fn get_lock_owner(f: &std::path::Path) -> Option<u64> { + use std::fs::File; + use std::io::{BufRead, BufReader}; + use std::os::unix::fs::MetadataExt; + + let lock_inode = std::fs::metadata(f).ok()?.ino(); + let lockfile = File::open("/proc/locks").ok()?; + BufReader::new(lockfile).lines().find_map(|line| { + // pid--vvvvvv vvvvvvv--- inode + // 21: FLOCK ADVISORY WRITE 359238 08:02:3719774 0 EOF + let line = line.ok()?; + let parts = line.split_whitespace().collect::<Vec<_>>(); + let (pid, inode) = (parts[4].parse::<u64>().ok()?, &parts[5]); + let inode = inode.rsplit_once(':')?.1.parse::<u64>().ok()?; + if inode == lock_inode { Some(pid) } else { None } + }) +} + +#[cfg(not(target_os = "linux"))] +fn get_lock_owner(_: &std::path::Path) -> Option<u64> { + // FIXME: Implement on other OS's + None +} |