[U-Boot] [PATCH V2 1/8] test/py: fix timeout to be absolute

[Stephen Warren]

From: Stephen Warren <swarren at nvidia.com>

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 at nvidia.com>
Reviewed-by: Lukasz Majewski <l.majewski at samsung.com>
Acked-by: Simon Glass <sjg at chromium.org>
---
 test/py/u_boot_spawn.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/test/py/u_boot_spawn.py b/test/py/u_boot_spawn.py
index 1baee63df25c..df4c67597cab 100644
--- 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)
-- 
2.7.0