Added SafeRename to better handle problems with git processes locking directories.
This solves a problem with "os.rename" sometimes failing with an
exception after cloning a dependency to a temporary directory. It's
possible the dying git processes still hold a handle to the directory.
Since gclient delete the temporary directory regardless of the success
of the process, it results in a lot of GB downloaded for nothing.
SafeRename solves this by retrying a few times if the renaming fails,
sleeping one second every time to get other processes the time to
release their lock on the directory. It gives up retrying after 15 times.
BUG=
R=maruel@chromium.org
Review URL: https://chromiumcodereview.appspot.com/23875041
git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@224372 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/gclient_utils.py b/gclient_utils.py
index 8385deb..e3c504a 100644
--- a/gclient_utils.py
+++ b/gclient_utils.py
@@ -96,6 +96,29 @@
f.write(content)
+def safe_rename(old, new):
+ """Renames a file reliably.
+
+ Sometimes os.rename does not work because a dying git process keeps a handle
+ on it for a few seconds. An exception is then thrown, which make the program
+ give up what it was doing and remove what was deleted.
+ The only solution is to catch the exception and try again until it works.
+ """
+ # roughly 10s
+ retries = 100
+ for i in range(retries):
+ try:
+ os.rename(old, new)
+ break
+ except OSError:
+ if i == (retries - 1):
+ # Give up.
+ raise
+ # retry
+ logging.debug("Renaming failed from %s to %s. Retrying ..." % (old, new))
+ time.sleep(0.1)
+
+
def rmtree(path):
"""shutil.rmtree() on steroids.