print stdout/stderr during runtime

If pyjustest is used with a test command, that prints an input request
to stdout and afterwards waits for the input, it waits forever. The
reason for this is, that stdout and stderr is printed only after the
test command was executed completely.

Instead of printing stdout and stderr after execution of the
test-command print it as it occurs.

This also provides meaningful timestamps if run in a timestamp wrapped
environment like jenkins.

Signed-off-by: Manuel Traut <manut@linutronix.de>
Reviewed-by: Anna-Maria Gleixner <anna-maria@linutronix.de>

1 files changed, 31 insertions, 10 deletions

diff --git a/pyjutest b/pyjutest
index 96766cb..ee04fdd 100755
--- a/pyjutest
+++ b/pyjutest
@@ -14,6 +14,7 @@ from subprocess import Popen, PIPE, STDOUT
 from optparse import OptionParser
 
 import os
+import select
 import sys
 import time
 
@@ -48,12 +49,39 @@ else:
 start = time.time()
 
 p = Popen(cmd, shell=True, stdout=PIPE, stderr=PIPE)
-out,err = p.communicate()
+fds = [ p.stdout, p.stderr ]
+
+out = ""
+err = ""
+
+while True:
+    readable, writable, exceptional = select.select(fds, [], [])
+    done = 0
+
+    if p.stderr in readable:
+        l = p.stderr.readline().decode('utf-8')
+        if len(l):
+            print(l[:-1], file=sys.stderr)
+            sys.stderr.flush()
+            err += l
+        else:
+            done = 1
+
+    if p.stdout in readable:
+        l = p.stdout.readline().decode('utf-8')
+        if len(l):
+            print(l[:-1])
+            sys.stdout.flush()
+            out += l
+        else:
+            if done:
+                break
+
+p.wait()
 
 duration = time.time() - start
 
-tc = TestCase(opt.uname, opt.uclass, duration, out[:-1].decode('utf-8'),
-              err[:-1].decode('utf-8'))
+tc = TestCase(opt.uname, opt.uclass, duration, out, err)
 
 if p.returncode:
 	tc.add_failure_info(err, "return: %d" % p.returncode)
@@ -65,10 +93,3 @@ with open('pyjutest.dat', 'wb') as dat:
 
 with open('pyjutest.xml', 'w') as xml:
 	TestSuite.to_file(xml, tss, prettyprint=True)
-
-print("%s STDOUT:" % opt.uname)
-for l in out.decode().split("\n"):
-    print(l)
-print("%s STDERR:" % opt.uname)
-for l in err.decode().split("\n"):
-    print(l, file=sys.stderr)