With BSD locks we don't have to guard against reading our own
temproots.
This commit is contained in:
Eelco Dolstra 2019-08-02 18:37:55 +02:00
parent e349f2c0a3
commit a2597d5f27
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@ -221,26 +221,22 @@ void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor)
//FDPtr fd(new AutoCloseFD(openLockFile(path, false)));
//if (*fd == -1) continue;
if (path != fnTempRoots) {
/* Try to acquire a write lock without blocking. This can
only succeed if the owning process has died. In that case
we don't care about its temporary roots. */
if (lockFile(fd->get(), ltWrite, false)) {
printError(format("removing stale temporary roots file '%1%'") % path);
unlink(path.c_str());
writeFull(fd->get(), "d");
continue;
}
/* Acquire a read lock. This will prevent the owning process
from upgrading to a write lock, therefore it will block in
addTempRoot(). */
debug(format("waiting for read lock on '%1%'") % path);
lockFile(fd->get(), ltRead, true);
/* Try to acquire a write lock without blocking. This can
only succeed if the owning process has died. In that case
we don't care about its temporary roots. */
if (lockFile(fd->get(), ltWrite, false)) {
printError(format("removing stale temporary roots file '%1%'") % path);
unlink(path.c_str());
writeFull(fd->get(), "d");
continue;
}
/* Acquire a read lock. This will prevent the owning process
from upgrading to a write lock, therefore it will block in
addTempRoot(). */
debug(format("waiting for read lock on '%1%'") % path);
lockFile(fd->get(), ltRead, true);
/* Read the entire file. */
string contents = readFile(fd->get());