diff options
Diffstat (limited to 'src/libstore')
| -rw-r--r-- | src/libstore/gc.cc | 26 | ||||
| -rw-r--r-- | src/libstore/gc.hh | 4 | ||||
| -rw-r--r-- | src/libstore/pathlocks.cc | 5 |
3 files changed, 31 insertions, 4 deletions
diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc index 4c6a944b89ce..e7321449e7a1 100644 --- a/src/libstore/gc.cc +++ b/src/libstore/gc.cc @@ -194,9 +194,35 @@ void collectGarbage(const PathSet & roots, GCAction action, debug(format("dead path `%1%'") % path); result.insert(path); + AutoCloseFD fdLock; + if (action == gcDeleteDead) { printMsg(lvlInfo, format("deleting `%1%'") % path); + + /* Only delete a lock file if we can acquire a write lock + on it. That means that it's either stale, or the + process that created it hasn't locked it yet. In the + latter case the other process will detect that we + deleted the lock, and retry (see pathlocks.cc). */ + if (path.size() >= 5 && string(path, path.size() - 5) == ".lock") { + + fdLock = open(path.c_str(), O_RDWR); + if (fdLock == -1) { + if (errno == ENOENT) continue; + throw SysError(format("opening lock file `%1%'") % path); + } + + if (!lockFile(fdLock, ltWrite, false)) { + debug(format("skipping active lock `%1%'") % path); + continue; + } + } + deleteFromStore(path); + + if (fdLock != -1) + /* Write token to stale (deleted) lock file. */ + writeFull(fdLock, (const unsigned char *) "d", 1); } /* Only delete lock files if the path is belongs to doesn't diff --git a/src/libstore/gc.hh b/src/libstore/gc.hh index 838188adeb82..c8f908b152aa 100644 --- a/src/libstore/gc.hh +++ b/src/libstore/gc.hh @@ -16,7 +16,9 @@ void collectGarbage(const PathSet & roots, GCAction action, PathSet & result); /* Register a temporary GC root. This root will automatically - disappear when this process exits. */ + disappear when this process exits. WARNING: this function should + not be called inside a BDB transaction, otherwise we can + deadlock. */ void addTempRoot(const Path & path); diff --git a/src/libstore/pathlocks.cc b/src/libstore/pathlocks.cc index a92b2225a51c..3beb49aac803 100644 --- a/src/libstore/pathlocks.cc +++ b/src/libstore/pathlocks.cc @@ -127,9 +127,8 @@ PathLocks::~PathLocks() /* Write a (meaningless) token to the file to indicate to other processes waiting on this lock that the lock is stale (deleted). */ - if (write(i->first, "d", 1) == 1) { - unlink(i->second.c_str()); - } + unlink(i->second.c_str()); + writeFull(i->first, (const unsigned char *) "d", 1); /* Note that the result of unlink() is ignored; removing the lock file is an optimisation, not a necessity. */ } |