test/py: fix timeout to be absolute

Currently, Spawn.expect() imposes its timeout solely upon receipt of new
data, not on its overall operation. In theory, this could cause the
timeout not to fire if U-Boot continually generated output that did not
match the expected patterns.

Fix the code to additionally impose a timeout on overall operation, which
is the intended mode of operation.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>

diff --git a/test/py/u_boot_spawn.py b/test/py/u_boot_spawn.py
index 1baee63df25c272e33de70e14b4234d5d9c1d14a..df4c67597cab77a59e677dfc8b7e8a6065194a99 100644 (file)
--- a/test/py/u_boot_spawn.py
+++ b/test/py/u_boot_spawn.py
@@ -122,6 +122,7 @@ class Spawn(object):
             if type(patterns[pi]) == type(''):
                 patterns[pi] = re.compile(patterns[pi])
 
+        tstart_s = time.time()
         try:
             while True:
                 earliest_m = None
@@ -142,7 +143,11 @@ class Spawn(object):
                     self.after = self.buf[pos:posafter]
                     self.buf = self.buf[posafter:]
                     return earliest_pi
-                events = self.poll.poll(self.timeout)
+                tnow_s = time.time()
+                tdelta_ms = (tnow_s - tstart_s) * 1000
+                if tdelta_ms > self.timeout:
+                    raise Timeout()
+                events = self.poll.poll(self.timeout - tdelta_ms)
                 if not events:
                     raise Timeout()
                 c = os.read(self.fd, 1024)