For non-detached processes, manually read and print out stdout and stderr.

   By default, the subprocess is supposed to inherit these from its parent,
 however when run under buildbot, it seems unable to read data
 from a grandchild process, so we have to read the child and print the data
 as if it came from us for buildbot to read it.  We're not sure why this is
 necessary.

Review URL: http://codereview.chromium.org/15092

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@7337 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 31 insertions, 1 deletions

diff --git a/tools/purify/common.py b/tools/purify/common.py
index 8414bdb..13555f6 100644
--- a/tools/purify/common.py
+++ b/tools/purify/common.py
@@ -49,6 +49,15 @@ QUANTIFYW_PATH = os.path.join(PPLUS_PATH, "quantifyw.exe")
 class TimeoutError(Exception): pass
 
 
+def _print_line(line, flush=True):
+  # Printing to a text file (including stdout) on Windows always winds up
+  # using \r\n automatically.  On buildbot, this winds up being read by a master
+  # running on Linux, so this is a pain.  Unfortunately, it doesn't matter what
+  # we do here, so just leave this comment for future reference.
+  print line,
+  if flush:
+    sys.stdout.flush()
+
 def RunSubprocess(proc, timeout=0, detach=False):
   """ Runs a subprocess, polling every .2 seconds until it finishes or until
   timeout is reached.  Then kills the process with taskkill.  A timeout <= 0
@@ -67,14 +76,35 @@ def RunSubprocess(proc, timeout=0, detach=False):
     DETACHED_PROCESS = 0x8
     p = subprocess.Popen(proc, creationflags=DETACHED_PROCESS)
   else:
-    p = subprocess.Popen(proc)
+    # For non-detached processes, manually read and print out stdout and stderr.
+    # By default, the subprocess is supposed to inherit these from its parent,
+    # however when run under buildbot, it seems unable to read data from a
+    # grandchild process, so we have to read the child and print the data as if
+    # it came from us for buildbot to read it.  We're not sure why this is
+    # necessary.
+    # TODO(erikkay): should we buffer stderr and stdout separately?
+    p = subprocess.Popen(proc, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
   if timeout <= 0:
     while p.poll() is None:
+      if not detach:
+        line = p.stdout.readline()
+        while line:
+          _print_line(line)
+          line = p.stdout.readline()
       time.sleep(0.2)
   else:
     wait_until = time.time() + timeout
     while p.poll() is None and time.time() < wait_until:
+      if not detach:
+        line = p.stdout.readline()
+        while line:
+          _print_line(line)
+          line = p.stdout.readline()
       time.sleep(0.2)
+  if not detach:
+    for line in p.stdout.readlines():
+      _print_line(line, False)
+    p.stdout.flush()
   result = p.poll()
   if result is None:
     subprocess.call(["taskkill", "/T", "/F", "/PID", str(p.pid)])