[GNUnet-SVN] r26340 - gnunet/src/testbed

[gnunet]

Author: harsha
Date: 2013-03-06 16:17:14 +0100 (Wed, 06 Mar 2013)
New Revision: 26340

Modified:
   gnunet/src/testbed/gnunet-helper-testbed.c
   gnunet/src/testbed/test_gnunet_helper_testbed.c
Log:
Don't call gnunet scheduler from signal handler.  Instead, write to a pipe
(ARM-style) to run a scheduler task when signal is received.


Modified: gnunet/src/testbed/gnunet-helper-testbed.c
===================================================================
--- gnunet/src/testbed/gnunet-helper-testbed.c  2013-03-06 14:55:27 UTC (rev 
26339)
+++ gnunet/src/testbed/gnunet-helper-testbed.c  2013-03-06 15:17:14 UTC (rev 
26340)
@@ -109,6 +109,11 @@
 static struct GNUNET_OS_Process *testbed;
 
 /**
+ * Pipe used to communicate shutdown via signal.
+ */
+static struct GNUNET_DISK_PipeHandle *sigpipe;
+
+/**
  * Task identifier for the read task
  */
 static GNUNET_SCHEDULER_TaskIdentifier read_task_id;
@@ -119,6 +124,11 @@
 static GNUNET_SCHEDULER_TaskIdentifier write_task_id;
 
 /**
+ * Task to kill the child
+ */
+static GNUNET_SCHEDULER_TaskIdentifier child_death_task_id;
+
+/**
  * Are we done reading messages from stdin?
  */
 static int done_reading;
@@ -166,15 +176,7 @@
   {
     LOG_DEBUG ("Killing testbed\n");
     GNUNET_break (0 == GNUNET_OS_process_kill (testbed, SIGTERM));
-    GNUNET_assert (GNUNET_OK == GNUNET_OS_process_wait (testbed));
-    GNUNET_OS_process_destroy (testbed);
-    testbed = NULL;
   }
-  if (NULL != test_system)
-  {
-    GNUNET_TESTING_system_destroy (test_system, GNUNET_YES);
-    test_system = NULL;
-  }
 }
 
 
@@ -414,6 +416,42 @@
 
 
 /**
+ * Task triggered whenever we receive a SIGCHLD (child
+ * process died).
+ *
+ * @param cls closure, NULL if we need to self-restart
+ * @param tc context
+ */
+static void
+child_death_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  const struct GNUNET_DISK_FileHandle *pr;
+  char c[16];
+
+  pr = GNUNET_DISK_pipe_handle (sigpipe, GNUNET_DISK_PIPE_END_READ);
+  child_death_task_id = GNUNET_SCHEDULER_NO_TASK;
+  if (0 == (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY))
+  {
+    child_death_task_id =
+       GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
+                                       pr, &child_death_task, NULL);
+    return;
+  }
+  /* consume the signal */
+  GNUNET_break (0 < GNUNET_DISK_file_read (pr, &c, sizeof (c)));
+  LOG_DEBUG ("Child died\n");
+  GNUNET_assert (GNUNET_OK == GNUNET_OS_process_wait (testbed));
+  GNUNET_OS_process_destroy (testbed);
+  testbed = NULL;
+  if (NULL != test_system)
+  {
+    GNUNET_TESTING_system_destroy (test_system, GNUNET_YES);
+    test_system = NULL;
+  }
+}
+
+
+/**
  * Main function that will be run.
  *
  * @param cls closure
@@ -434,6 +472,11 @@
                                       &read_task, NULL);
   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
                                 NULL);
+  child_death_task_id =
+    GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
+                                   GNUNET_DISK_pipe_handle (sigpipe,
+                                                            
GNUNET_DISK_PIPE_END_READ),
+                                   &child_death_task, NULL);
 }
 
 
@@ -443,14 +486,15 @@
 static void
 sighandler_child_death ()
 {
-  if ((NULL != testbed) && (GNUNET_NO == in_shutdown))
-  {
-    LOG_DEBUG ("Child died\n");
-    GNUNET_assert (GNUNET_OK == GNUNET_OS_process_wait (testbed));
-    GNUNET_OS_process_destroy (testbed);
-    testbed = NULL;
-    GNUNET_SCHEDULER_shutdown ();       /* We are done too! */
-  }
+  static char c;
+  int old_errno;       /* back-up errno */
+
+  old_errno = errno;
+  GNUNET_break (1 ==
+                GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle
+                                        (sigpipe, GNUNET_DISK_PIPE_END_WRITE),
+                                        &c, sizeof (c)));
+  errno = old_errno;
 }
 
 
@@ -473,6 +517,13 @@
 
   status = GNUNET_OK;
   in_shutdown = GNUNET_NO;
+  if (NULL == (sigpipe = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, 
+                                           GNUNET_NO, GNUNET_NO)))
+  {
+    GNUNET_break (0);
+    ret = GNUNET_SYSERR;
+    return 1;
+  }
   shc_chld =
       GNUNET_SIGNAL_handler_install (GNUNET_SIGCHLD, &sighandler_child_death);
   ret =
@@ -481,6 +532,7 @@
                           &run, NULL);
   GNUNET_SIGNAL_handler_uninstall (shc_chld);
   shc_chld = NULL;
+  GNUNET_DISK_pipe_close (sigpipe);
   if (GNUNET_OK != ret)
     return 1;
   return (GNUNET_OK == status) ? 0 : 1;

Modified: gnunet/src/testbed/test_gnunet_helper_testbed.c
===================================================================
--- gnunet/src/testbed/test_gnunet_helper_testbed.c     2013-03-06 14:55:27 UTC 
(rev 26339)
+++ gnunet/src/testbed/test_gnunet_helper_testbed.c     2013-03-06 15:17:14 UTC 
(rev 26340)
@@ -206,14 +206,14 @@
     "gnunet-helper-testbed",
     NULL
   };
-  const char *controller_name = "127.0.0.1";
+  const char *trusted_ip = "127.0.0.1";
 
   helper =
       GNUNET_HELPER_start (GNUNET_YES, "gnunet-helper-testbed", binary_argv,
                            &mst_cb, &exp_cb, NULL);
   GNUNET_assert (NULL != helper);
   cfg = GNUNET_CONFIGURATION_dup (cfg2);
-  msg = GNUNET_TESTBED_create_helper_init_msg_ (controller_name, NULL, cfg);
+  msg = GNUNET_TESTBED_create_helper_init_msg_ (trusted_ip, NULL, cfg);
   shandle =
       GNUNET_HELPER_send (helper, &msg->header, GNUNET_NO, &cont_cb, NULL);
   GNUNET_assert (NULL != shandle);