Add automatic auto-flushing stdout.
An automated work around for python lack of stdout flushing.
This design simplifies life once parallel checkout is enabled.
TEST=none
BUG=none
Review URL: http://codereview.chromium.org/3342024
git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@58819 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/gclient_utils.py b/gclient_utils.py
index d21ade5..9d14bd2 100644
--- a/gclient_utils.py
+++ b/gclient_utils.py
@@ -285,6 +285,30 @@
return CheckCallAndFilter(args, **kwargs)
+class StdoutAutoFlush(object):
+ """Automatically flush after N seconds."""
+ def __init__(self, stdout, delay=10):
+ self.lock = threading.Lock()
+ self.stdout = stdout
+ self.delay = delay
+ self.last_flushed_at = time.time()
+ self.stdout.flush()
+
+ def write(self, out):
+ """Thread-safe."""
+ self.stdout.write(out)
+ should_flush = False
+ with self.lock:
+ if (time.time() - self.last_flushed_at) > self.delay:
+ should_flush = True
+ self.last_flushed_at = time.time()
+ if should_flush:
+ self.stdout.flush()
+
+ def flush(self):
+ self.stdout.flush()
+
+
def CheckCallAndFilter(args, stdout=None, filter_fn=None,
print_stdout=None, call_filter_on_first_line=False,
**kwargs):
@@ -308,7 +332,6 @@
**kwargs)
# Do a flush of stdout before we begin reading from the subprocess's stdout
- last_flushed_at = time.time()
stdout.flush()
# Also, we need to forward stdout to prevent weird re-ordering of output.
@@ -329,12 +352,6 @@
else:
filter_fn(in_line)
in_line = ''
- # Flush at least 10 seconds between line writes. We wait at least 10
- # seconds to avoid overloading the reader that called us with output,
- # which can slow busy readers down.
- if (time.time() - last_flushed_at) > 10:
- last_flushed_at = time.time()
- stdout.flush()
in_byte = kid.stdout.read(1)
# Flush the rest of buffered output. This is only an issue with
# stdout/stderr not ending with a \n.