diff options
| -rw-r--r-- | lib/git/index.py | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/lib/git/index.py b/lib/git/index.py index 991c77da..041dfff7 100644 --- a/lib/git/index.py +++ b/lib/git/index.py @@ -21,7 +21,7 @@ import git.diff as diff from errors import GitCommandError from git.objects import Blob, Tree, Object, Commit -from git.utils import SHA1Writer, LazyMixin, ConcurrentWriteOperation, join_path_native +from git.utils import SHA1Writer, LazyMixin, ConcurrentWriteOperation, join_path_native, BlockingLockFile class CheckoutError( Exception ): @@ -70,6 +70,38 @@ class _TemporaryFileSwap(object): os.rename(self.tmp_file_path, self.file_path) # END temp file exists +class IndexLock(BlockingLockFile): + """Specialized lock that will wait for the index to be locked and immediately + move the lock out of the way. This allows a git command to take the lock + which has to follow right after the lock() call. + + Right before the lock is released, we will move our original lock back into place. + This lock should be used to gain fine-grained control over multiple processes + or threads that try to manipulate the index and would otherwise fail. + Using this lock, these will wait for each other. + + NOTE: + There is still a small chance that git will fail as file system + operations take time as well. + """ + __slots__ = '_tmp_file_path' + + def _obtain_lock_or_raise(self): + super(IndexLock, self)._obtain_lock_or_raise() + self._tmp_file_path = self._lock_file_path() + tempfile.mktemp('','','') + # rename lock we aquired to move it out of the way + os.rename(self._lock_file_path(), self._tmp_file_path) + + def _release_lock(self): + # move our lock back into place + if hasattr(self, '_tmp_file_path') and os.path.isfile(self._tmp_file_path): + lock_file = self._lock_file_path() + if os.name == 'nt' and os.path.exists(lock_file): + os.remove(lock_file) + os.rename(self._tmp_file_path, lock_file) + # END temp file exists + super(IndexLock, self)._release_lock() + class BlobFilter(object): """ Predicate to be used by iter_blobs allowing to filter only return blobs which |