[lnst] Tests: allow to interrupt running test and get its result

[Jiří Pírko]

commit d9d07ef1ee8863b7598e147ccb8d4952e2f78461
Author: Jiri Pirko 
Date:   Fri Jul 1 14:09:49 2011 +0200

Tests: allow to interrupt running test and get its result

Signed-off-by: Jiri Pirko

Common/TestsCommon.py     |   28 ++++++++++++++++++++++++++--
 NetTest/NetTestCommand.py |   40 +++++++++++++++++++++++++---------------
 2 files changed, 51 insertions(+), 17 deletions(-)
---
diff --git a/Common/TestsCommon.py b/Common/TestsCommon.py
index 197bb62..1e275ca 100644
--- a/Common/TestsCommon.py
+++ b/Common/TestsCommon.py
@@ -10,7 +10,11 @@ __author__ = """
 [e-mail] (Jiri Pirko)
 """

-import re, logging, sys, os
+import re
+import logging
+import sys
+import os
+import signal
 from NetTest.NetTestCommand import NetTestCommandGeneric

class testLogger(logging.Logger):
@@ -51,8 +55,28 @@ class TestOptionMissing(Exception):

class TestGeneric(NetTestCommandGeneric):
     def __init__(self, command):
-        self._command = command
         self._testLogger = logging.getLogger("root.testLogger")
+        self._read_pipe, self._write_pipe = os.pipe()
+        signal.signal(signal.SIGINT, self._signal_intr_handler)
+        NetTestCommandGeneric.__init__(self, command)
+
+    def __del__(self):
+        os.close(self._read_pipe)
+        os.close(self._write_pipe)
+
+    def _signal_intr_handler(self, signum, frame):
+        os.write(self._write_pipe, "a")
+    
+    def wait_on_interrupt(self):
+        '''
+        Should be used by test implementation for waiting on SIGINT
+        '''
+        while True:
+            try:
+                os.read(self._read_pipe, 1)
+            except OSError:
+                continue
+            break

def set_fail(self, err_msg, res_data = None):
         self._testLogger.error("FAILED - %s" % err_msg)
diff --git a/NetTest/NetTestCommand.py b/NetTest/NetTestCommand.py
index 0c9bc54..24f432c 100644
--- a/NetTest/NetTestCommand.py
+++ b/NetTest/NetTestCommand.py
@@ -67,6 +67,7 @@ def NetTestCommandTest(command):
 class NetTestCommandGeneric:
     def __init__(self, command):
         self._command = command
+        self._result = None

def run(self):
         pass
@@ -75,6 +76,12 @@ class NetTestCommandGeneric:
         self._result = result

def get_result(self):
+        if not self._result:
+            '''
+            In case result is not set yet, it most likely means that
+            command was killed. So set pass in this case
+            '''
+            self.set_pass()
         return self._result

def set_fail(self, err_msg):
@@ -95,27 +102,30 @@ class NetTestCommandExec(NetTestCommandGeneric):
         except ExecCmdFail:
             self.set_fail("Command failed to execute")

-
 class BgProcessException(Exception):
     """Base class for client errors."""
     def __init__(self, str):
-        self.str = str
+        self._str = str

def __str__(self):
-        return "BgProcessError: " + self.str
+        return "BgProcessError: " + self._str
+
+def get_bg_process_result(bg_id):
+    pipe = bg_processes.get_pipe(bg_id)
+    tmp = os.read(pipe, 4096*10)
+    result = pickle.loads(tmp)
+    if "Exception" in result:
+        raise BgProcessException(result["Exception"])
+    os.close(pipe)
+    return result

class NetTestCommandWait(NetTestCommandGeneric):
     def run(self):
         bg_id = int(self._command["value"])
         pid = bg_processes.get_pid(bg_id)
-        pipe = bg_processes.get_pipe(bg_id)
         logging.debug("Waiting for background id "%d", pid "%d"" % (bg_id, pid))
         os.waitpid(pid, 0)
-        tmp = os.read(pipe, 4096*10)
-        result = pickle.loads(tmp)
-        if "Exception" in result:
-            raise BgProcessException(result["Exception"])
-        os.close(pipe)
+        result = get_bg_process_result(bg_id)
         bg_processes.remove(bg_id)
         self.set_result(result)

@@ -125,8 +135,10 @@ class NetTestCommandKill(NetTestCommandGeneric):
         pid = bg_processes.get_pid(bg_id)
         logging.debug("Killing background id "%d", pid "%d"" % (bg_id, pid))
         os.killpg(os.getpgid(pid), signal.SIGINT)
+        os.waitpid(pid, 0)
+        result = get_bg_process_result(bg_id)
         bg_processes.remove(bg_id)
-        self.set_result({"passed": True})
+        self.set_result(result)

def get_command_class(command):
     cmd_type = command["type"]
@@ -164,15 +176,13 @@ class NetTestCommand:
             try:
                 cmd_cls.run()
                 result = cmd_cls.get_result()
-                tmp = pickle.dumps(result)
-                os.write(write_pipe, tmp)
             except KeyboardInterrupt:
-                pass
+                result = cmd_cls.get_result()
             except:
                 type, value, tb = sys.exc_info()
                 result = {"Exception": ''.join(traceback.format_exception(type, value, tb))}
-                tmp = pickle.dumps(result)
-                os.write(write_pipe, tmp)
+            tmp = pickle.dumps(result)
+            os.write(write_pipe, tmp)
             os.close(write_pipe)
             os._exit(0)
         else: