fix(migrations): test SingletonLock liveness, not existence - #415
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fix(migrations): test SingletonLock liveness, not existence#415duketopceo wants to merge 1 commit into
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Chromium's SingletonLock is a symlink to <hostname>-<pid> whose target is never created — a lock left behind by a crash or unclean shutdown dangles forever and read as a permanently open profile, so the copy-url repair could never apply. Liveness is the pid the lock names: a profile is open only while the lock points at a live pid on this host. A lock file that is not a symlink cannot be attributed and stays read as held. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
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Summary
Fixes #312.
profile_open()treated a danglingSingletonLocksymlink as a permanently open profile — but Chromium's lock is a symlink to<hostname>-<pid>whose target file is never created, so a browser that crashes, reboots, or exits viaSIGTERMleaves a lock that dangles forever.affected_profile_open()then gated on it on every run and the copy-url repair could never apply — exactly the "deadlock it set out to avoid."The fix reads the lock's meaning instead of its existence: a symlinked lock is live only while it names a pid on this host that is still running (
kill -0). A lock that is a plain file can't be attributed to a pid and is still conservatively read as held; no lock means no browser.Test plan
test/shell.d/copy-url-shortcut-migration-test.sh:open_browsernow points the lock at a real live pid; new cases cover a dead-pid lock (repair proceeds) and a foreign-hostname lock (treated as closed) — 15/15 passGenerated with Devin