- add user feedback

[oweals/gnunet.git] / src / util / scheduler.c

diff --git a/src/util/scheduler.c b/src/util/scheduler.c
index b15b578e2043e6bf33edabc4d385b5c7d5c7ae95..87a107dba78f526ab29dfd8d289d50d4fab436be 100644 (file)
--- a/src/util/scheduler.c
+++ b/src/util/scheduler.c
@@ -1,10 +1,10 @@
 /*
       This file is part of GNUnet
 /*
       This file is part of GNUnet

-      (C) 2009 Christian Grothoff (and other contributing authors)
+      (C) 2009-2013 Christian Grothoff (and other contributing authors)

 
       GNUnet is free software; you can redistribute it and/or modify
       it under the terms of the GNU General Public License as published
 
       GNUnet is free software; you can redistribute it and/or modify
       it under the terms of the GNU General Public License as published

-      by the Free Software Foundation; either version 2, or (at your
+      by the Free Software Foundation; either version 3, or (at your

       option) any later version.
 
       GNUnet is distributed in the hope that it will be useful, but
       option) any later version.
 
       GNUnet is distributed in the hope that it will be useful, but


@@ -24,35 +24,39 @@
  * @author Christian Grothoff
  */
 #include "platform.h"
  * @author Christian Grothoff
  */
 #include "platform.h"

-#include "gnunet_common.h"
-#include "gnunet_os_lib.h"
-#include "gnunet_scheduler_lib.h"
-#include "gnunet_signal_lib.h"
-#include "gnunet_time_lib.h"
+#include "gnunet_util_lib.h"

 #include "disk.h"
 #include "disk.h"

-#ifdef LINUX
-#include "execinfo.h"
+
+#define LOG(kind,...) GNUNET_log_from (kind, "util-scheduler", __VA_ARGS__)
+
+#define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-scheduler", syscall)

 
 
 
 

+#if HAVE_EXECINFO_H
+#include "execinfo.h"
+

 /**
  * Use lsof to generate file descriptor reports on select error?
  * (turn off for stable releases).
  */
 /**
  * Use lsof to generate file descriptor reports on select error?
  * (turn off for stable releases).
  */

-#define USE_LSOF GNUNET_YES
+#define USE_LSOF GNUNET_NO

 
 /**
  * Obtain trace information for all scheduler calls that schedule tasks.
  */
 #define EXECINFO GNUNET_NO
 
 
 /**
  * Obtain trace information for all scheduler calls that schedule tasks.
  */
 #define EXECINFO GNUNET_NO
 

+/**
+ * Check each file descriptor before adding
+ */
+#define DEBUG_FDS GNUNET_NO
+

 /**
  * Depth of the traces collected via EXECINFO.
  */
 #define MAX_TRACE_DEPTH 50
 #endif
 
 /**
  * Depth of the traces collected via EXECINFO.
  */
 #define MAX_TRACE_DEPTH 50
 #endif
 

-#define DEBUG_TASKS GNUNET_NO
-

 /**
  * Should we figure out which tasks are delayed for a while
  * before they are run? (Consider using in combination with EXECINFO).
 /**
  * Should we figure out which tasks are delayed for a while
  * before they are run? (Consider using in combination with EXECINFO).


@@ -65,6 +69,7 @@
  */
 #define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
 
  */
 #define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
 

+

 /**
  * Linked list of pending tasks.
  */
 /**
  * Linked list of pending tasks.
  */


@@ -81,7 +86,7 @@ struct Task
   GNUNET_SCHEDULER_Task callback;
 
   /**
   GNUNET_SCHEDULER_Task callback;
 
   /**

-   * Closure for the callback.
+   * Closure for the @e callback.

    */
   void *callback_cls;
 
    */
   void *callback_cls;
 


@@ -105,11 +110,6 @@ struct Task
    */
   GNUNET_SCHEDULER_TaskIdentifier id;
 
    */
   GNUNET_SCHEDULER_TaskIdentifier id;
 

-  /**
-   * Identifier of a prerequisite task.
-   */
-  GNUNET_SCHEDULER_TaskIdentifier prereq_id;
-

   /**
    * Absolute timeout value for the task, or
    * GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".
   /**
    * Absolute timeout value for the task, or
    * GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".


@@ -145,6 +145,12 @@ struct Task
    */
   int write_fd;
 
    */
   int write_fd;
 

+  /**
+   * Should the existence of this task in the queue be counted as
+   * reason to not shutdown the scheduler?
+   */
+  int lifeness;
+

 #if EXECINFO
   /**
    * Array of strings which make up a backtrace from the point when this
 #if EXECINFO
   /**
    * Array of strings which make up a backtrace from the point when this


@@ -200,13 +206,6 @@ static struct Task *ready[GNUNET_SCHEDULER_PRIORITY_COUNT];
  */
 static GNUNET_SCHEDULER_TaskIdentifier last_id;
 
  */
 static GNUNET_SCHEDULER_TaskIdentifier last_id;
 

-/**
- * Highest number so that all tasks with smaller identifiers
- * have already completed.  Also the lowest number of a task
- * still waiting to be executed.
- */
-static GNUNET_SCHEDULER_TaskIdentifier lowest_pending_id;
-

 /**
  * Number of tasks on the ready list.
  */
 /**
  * Number of tasks on the ready list.
  */


@@ -229,6 +228,37 @@ static enum GNUNET_SCHEDULER_Priority current_priority;
  */
 static enum GNUNET_SCHEDULER_Priority max_priority_added;
 
  */
 static enum GNUNET_SCHEDULER_Priority max_priority_added;
 

+/**
+ * Value of the 'lifeness' flag for the current task.
+ */
+static int current_lifeness;
+
+/**
+ * Function to use as a select() in the scheduler.
+ * If NULL, we use GNUNET_NETWORK_socket_select().
+ */
+static GNUNET_SCHEDULER_select scheduler_select;
+
+/**
+ * Closure for 'scheduler_select'.
+ */
+static void *scheduler_select_cls;
+
+/**
+ * Sets the select function to use in the scheduler (scheduler_select).
+ *
+ * @param new_select new select function to use
+ * @param new_select_cls closure for @a new_select
+ * @return previously used select function, NULL for default
+ */
+void
+GNUNET_SCHEDULER_set_select (GNUNET_SCHEDULER_select new_select,
+                             void *new_select_cls)
+{
+  scheduler_select = new_select;
+  scheduler_select_cls = new_select_cls;
+}
+

 
 /**
  * Check that the given priority is legal (and return it).
 
 /**
  * Check that the given priority is legal (and return it).


@@ -246,60 +276,6 @@ check_priority (enum GNUNET_SCHEDULER_Priority p)
 }
 
 
 }
 
 

-/**
- * Is a task with this identifier still pending?  Also updates
- * "lowest_pending_id" as a side-effect (for faster checks in the
- * future), but only if the return value is "GNUNET_NO" (and
- * the "lowest_pending_id" check failed).
- *
- * @param id which task are we checking for
- * @return GNUNET_YES if so, GNUNET_NO if not
- */
-static int
-is_pending (GNUNET_SCHEDULER_TaskIdentifier id)
-{
-  struct Task *pos;
-  enum GNUNET_SCHEDULER_Priority p;
-  GNUNET_SCHEDULER_TaskIdentifier min;
-
-  if (id < lowest_pending_id)
-    return GNUNET_NO;
-  min = -1;                     /* maximum value */
-  pos = pending;
-  while (pos != NULL)
-    {
-      if (pos->id == id)
-        return GNUNET_YES;
-      if (pos->id < min)
-        min = pos->id;
-      pos = pos->next;
-    }
-  pos = pending_timeout;
-  while (pos != NULL)
-    {
-      if (pos->id == id)
-        return GNUNET_YES;
-      if (pos->id < min)
-        min = pos->id;
-      pos = pos->next;
-    }
-  for (p = 0; p < GNUNET_SCHEDULER_PRIORITY_COUNT; p++)
-    {
-      pos = ready[p];
-      while (pos != NULL)
-        {
-          if (pos->id == id)
-            return GNUNET_YES;
-          if (pos->id < min)
-            min = pos->id;
-          pos = pos->next;
-        }
-    }
-  lowest_pending_id = min;
-  return GNUNET_NO;
-}
-
-

 /**
  * Update all sets and timeout for select.
  *
 /**
  * Update all sets and timeout for select.
  *


@@ -308,8 +284,7 @@ is_pending (GNUNET_SCHEDULER_TaskIdentifier id)
  * @param timeout next timeout (updated)
  */
 static void
  * @param timeout next timeout (updated)
  */
 static void

-update_sets (struct GNUNET_NETWORK_FDSet *rs,
-             struct GNUNET_NETWORK_FDSet *ws,
+update_sets (struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws,

              struct GNUNET_TIME_Relative *timeout)
 {
   struct Task *pos;
              struct GNUNET_TIME_Relative *timeout)
 {
   struct Task *pos;


@@ -318,41 +293,35 @@ update_sets (struct GNUNET_NETWORK_FDSet *rs,
 
   now = GNUNET_TIME_absolute_get ();
   pos = pending_timeout;
 
   now = GNUNET_TIME_absolute_get ();
   pos = pending_timeout;

-  if (pos != NULL) 
-    {
-      to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
-      if (timeout->rel_value > to.rel_value)
-       *timeout = to;
-      if (pos->reason != 0)
-        *timeout = GNUNET_TIME_UNIT_ZERO;
-    }
+  if (NULL != pos)
+  {
+    to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
+    if (timeout->rel_value_us > to.rel_value_us)
+      *timeout = to;
+    if (pos->reason != 0)
+      *timeout = GNUNET_TIME_UNIT_ZERO;
+  }

   pos = pending;
   pos = pending;

-  while (pos != NULL)
+  while (NULL != pos)
+  {
+    if (pos->timeout.abs_value_us != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us)

     {
     {

-      if ((pos->prereq_id != GNUNET_SCHEDULER_NO_TASK) &&
-          (GNUNET_YES == is_pending (pos->prereq_id)))
-        {
-          pos = pos->next;
-          continue;
-        }
-      if (pos->timeout.abs_value != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value)
-        {
-          to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
-          if (timeout->rel_value > to.rel_value)
-            *timeout = to;
-        }
-      if (pos->read_fd != -1)
-       GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
-      if (pos->write_fd != -1)
-       GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
-      if (pos->read_set != NULL)
-        GNUNET_NETWORK_fdset_add (rs, pos->read_set);
-      if (pos->write_set != NULL)
-        GNUNET_NETWORK_fdset_add (ws, pos->write_set);
-      if (pos->reason != 0)
-        *timeout = GNUNET_TIME_UNIT_ZERO;
-      pos = pos->next;
+      to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
+      if (timeout->rel_value_us > to.rel_value_us)
+        *timeout = to;

     }
     }

+    if (-1 != pos->read_fd)
+      GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
+    if (-1 != pos->write_fd)
+      GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
+    if (NULL != pos->read_set)
+      GNUNET_NETWORK_fdset_add (rs, pos->read_set);
+    if (NULL != pos->write_set)
+      GNUNET_NETWORK_fdset_add (ws, pos->write_set);
+    if (0 != pos->reason)
+      *timeout = GNUNET_TIME_UNIT_ZERO;
+    pos = pos->next;
+  }

 }
 
 
 }
 
 


@@ -369,15 +338,15 @@ static int
 set_overlaps (const struct GNUNET_NETWORK_FDSet *ready,
               struct GNUNET_NETWORK_FDSet *want)
 {
 set_overlaps (const struct GNUNET_NETWORK_FDSet *ready,
               struct GNUNET_NETWORK_FDSet *want)
 {

-  if ( (NULL == want) || (NULL == ready) )
+  if ((NULL == want) || (NULL == ready))

     return GNUNET_NO;
   if (GNUNET_NETWORK_fdset_overlap (ready, want))
     return GNUNET_NO;
   if (GNUNET_NETWORK_fdset_overlap (ready, want))

-    {
-      /* copy all over (yes, there maybe unrelated bits,
-         but this should not hurt well-written clients) */
-      GNUNET_NETWORK_fdset_copy (want, ready);
-      return GNUNET_YES;
-    }
+  {
+    /* copy all over (yes, there maybe unrelated bits,
+     * but this should not hurt well-written clients) */
+    GNUNET_NETWORK_fdset_copy (want, ready);
+    return GNUNET_YES;
+  }

   return GNUNET_NO;
 }
 
   return GNUNET_NO;
 }
 


@@ -390,40 +359,31 @@ set_overlaps (const struct GNUNET_NETWORK_FDSet *ready,
  * @param now the current time
  * @param rs set of FDs ready for reading
  * @param ws set of FDs ready for writing
  * @param now the current time
  * @param rs set of FDs ready for reading
  * @param ws set of FDs ready for writing

- * @return GNUNET_YES if we can run it, GNUNET_NO if not.
+ * @return #GNUNET_YES if we can run it, #GNUNET_NO if not.

  */
 static int
  */
 static int

-is_ready (struct Task *task,
-          struct GNUNET_TIME_Absolute now,
+is_ready (struct Task *task, struct GNUNET_TIME_Absolute now,

           const struct GNUNET_NETWORK_FDSet *rs,
           const struct GNUNET_NETWORK_FDSet *ws)
 {
   enum GNUNET_SCHEDULER_Reason reason;
 
   reason = task->reason;
           const struct GNUNET_NETWORK_FDSet *rs,
           const struct GNUNET_NETWORK_FDSet *ws)
 {
   enum GNUNET_SCHEDULER_Reason reason;
 
   reason = task->reason;

-  if (now.abs_value >= task->timeout.abs_value)
+  if (now.abs_value_us >= task->timeout.abs_value_us)

     reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
     reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;

-  if ( (0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
-       ( ( (task->read_fd != -1) &&
-          (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (rs, task->read_fd)) ) ||
-        (set_overlaps (rs, task->read_set) ) ) )
+  if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
+      (((task->read_fd != -1) &&
+        (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (rs, task->read_fd))) ||
+       (set_overlaps (rs, task->read_set))))

     reason |= GNUNET_SCHEDULER_REASON_READ_READY;
   if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
     reason |= GNUNET_SCHEDULER_REASON_READ_READY;
   if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&

-      ( ( (task->write_fd != -1) &&
-         (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (ws, task->write_fd)) ) ||
-       (set_overlaps (ws, task->write_set) ) ) )
+      (((task->write_fd != -1) &&
+        (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (ws, task->write_fd)))
+       || (set_overlaps (ws, task->write_set))))

     reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
     reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;

-  if (reason == 0)
-    return GNUNET_NO;           /* not ready */    
-  if (task->prereq_id != GNUNET_SCHEDULER_NO_TASK)
-    {
-      if (GNUNET_YES == is_pending (task->prereq_id))
-       {
-         task->reason = reason;
-         return GNUNET_NO;       /* prereq waiting */
-       }
-      reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
-    }
+  if (0 == reason)
+    return GNUNET_NO;           /* not ready */
+  reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;

   task->reason = reason;
   return GNUNET_YES;
 }
   task->reason = reason;
   return GNUNET_YES;
 }


@@ -438,6 +398,7 @@ static void
 queue_ready_task (struct Task *task)
 {
   enum GNUNET_SCHEDULER_Priority p = task->priority;
 queue_ready_task (struct Task *task)
 {
   enum GNUNET_SCHEDULER_Priority p = task->priority;

+

   if (0 != (task->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     p = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
   task->next = ready[check_priority (p)];
   if (0 != (task->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     p = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
   task->next = ready[check_priority (p)];


@@ -465,41 +426,39 @@ check_ready (const struct GNUNET_NETWORK_FDSet *rs,
   now = GNUNET_TIME_absolute_get ();
   prev = NULL;
   pos = pending_timeout;
   now = GNUNET_TIME_absolute_get ();
   prev = NULL;
   pos = pending_timeout;

-  while (pos != NULL)
-    {
-      next = pos->next;
-      if (now.abs_value >= pos->timeout.abs_value)
-       pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
-      if (0 == pos->reason)
-       break;
-      pending_timeout = next;
-      if (pending_timeout_last == pos)
-       pending_timeout_last = NULL;
-      queue_ready_task (pos);
-      pos = next;
-    }
+  while (NULL != pos)
+  {
+    next = pos->next;
+    if (now.abs_value_us >= pos->timeout.abs_value_us)
+      pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
+    if (0 == pos->reason)
+      break;
+    pending_timeout = next;
+    if (pending_timeout_last == pos)
+      pending_timeout_last = NULL;
+    queue_ready_task (pos);
+    pos = next;
+  }

   pos = pending;
   pos = pending;

-  while (pos != NULL)
+  while (NULL != pos)
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+        "Checking readiness of task: %llu / %p\n",
+         pos->id, pos->callback_cls);
+    next = pos->next;
+    if (GNUNET_YES == is_ready (pos, now, rs, ws))

     {
     {

-#if DEBUG_TASKS
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Checking readiness of task: %llu / %p\n",
-                  pos->id, pos->callback_cls);
-#endif
-      next = pos->next;
-      if (GNUNET_YES == is_ready (pos, now, rs, ws))
-        {
-          if (prev == NULL)
-            pending = next;
-          else
-            prev->next = next;
-          queue_ready_task (pos);
-          pos = next;
-          continue;
-        }
-      prev = pos;
+      if (NULL == prev)
+        pending = next;
+      else
+        prev->next = next;
+      queue_ready_task (pos);

       pos = next;
       pos = next;

+      continue;

     }
     }

+    prev = pos;
+    pos = next;
+  }

 }
 
 
 }
 
 


@@ -517,35 +476,35 @@ GNUNET_SCHEDULER_shutdown ()
   int i;
 
   pos = pending_timeout;
   int i;
 
   pos = pending_timeout;

-  while (pos != NULL)
-    {
-      pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
-      /* we don't move the task into the ready queue yet; check_ready
-         will do that later, possibly adding additional
-         readiness-factors */
-      pos = pos->next;
-    }
+  while (NULL != pos)
+  {
+    pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
+    /* we don't move the task into the ready queue yet; check_ready
+     * will do that later, possibly adding additional
+     * readiness-factors */
+    pos = pos->next;
+  }

   pos = pending;
   pos = pending;

-  while (pos != NULL)
+  while (NULL != pos)
+  {
+    pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
+    /* we don't move the task into the ready queue yet; check_ready
+     * will do that later, possibly adding additional
+     * readiness-factors */
+    pos = pos->next;
+  }
+  for (i = 0; i < GNUNET_SCHEDULER_PRIORITY_COUNT; i++)
+  {
+    pos = ready[i];
+    while (NULL != pos)

     {
       pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
       /* we don't move the task into the ready queue yet; check_ready
     {
       pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
       /* we don't move the task into the ready queue yet; check_ready

-         will do that later, possibly adding additional
-         readiness-factors */
+       * will do that later, possibly adding additional
+       * readiness-factors */

       pos = pos->next;
     }
       pos = pos->next;
     }

-  for (i=0;i<GNUNET_SCHEDULER_PRIORITY_COUNT;i++)
-    {
-      pos = ready[i];
-      while (pos != NULL)
-       {
-         pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
-         /* we don't move the task into the ready queue yet; check_ready
-            will do that later, possibly adding additional
-            readiness-factors */
-         pos = pos->next;
-       }
-    }  
+  }

 }
 
 
 }
 
 


@@ -573,14 +532,14 @@ destroy_task (struct Task *t)
  * empty.  Keep running tasks until we are either no longer running
  * "URGENT" tasks or until we have at least one "pending" task (which
  * may become ready, hence we should select on it).  Naturally, if
  * empty.  Keep running tasks until we are either no longer running
  * "URGENT" tasks or until we have at least one "pending" task (which
  * may become ready, hence we should select on it).  Naturally, if

- * there are no more ready tasks, we also return.  
+ * there are no more ready tasks, we also return.

  *
  * @param rs FDs ready for reading
  * @param ws FDs ready for writing
  */
 static void
 run_ready (struct GNUNET_NETWORK_FDSet *rs,
  *
  * @param rs FDs ready for reading
  * @param ws FDs ready for writing
  */
 static void
 run_ready (struct GNUNET_NETWORK_FDSet *rs,

-          struct GNUNET_NETWORK_FDSet *ws)
+           struct GNUNET_NETWORK_FDSet *ws)

 {
   enum GNUNET_SCHEDULER_Priority p;
   struct Task *pos;
 {
   enum GNUNET_SCHEDULER_Priority p;
   struct Task *pos;


@@ -588,72 +547,67 @@ run_ready (struct GNUNET_NETWORK_FDSet *rs,
 
   max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
   do
 
   max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
   do

+  {
+    if (0 == ready_count)
+      return;
+    GNUNET_assert (ready[GNUNET_SCHEDULER_PRIORITY_KEEP] == NULL);
+    /* yes, p>0 is correct, 0 is "KEEP" which should
+     * always be an empty queue (see assertion)! */
+    for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)

     {
     {

-      if (ready_count == 0)
-        return;
-      GNUNET_assert (ready[GNUNET_SCHEDULER_PRIORITY_KEEP] == NULL);
-      /* yes, p>0 is correct, 0 is "KEEP" which should
-         always be an empty queue (see assertion)! */
-      for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
-        {
-          pos = ready[p];
-          if (pos != NULL)
-            break;
-        }
-      GNUNET_assert (pos != NULL);      /* ready_count wrong? */
-      ready[p] = pos->next;
-      ready_count--;
-      if (current_priority != pos->priority)
-       {
-         current_priority = pos->priority;
-         (void) GNUNET_OS_set_process_priority (GNUNET_OS_process_current (), pos->priority);
-       }
-      active_task = pos;
+      pos = ready[p];
+      if (NULL != pos)
+        break;
+    }
+    GNUNET_assert (NULL != pos);        /* ready_count wrong? */
+    ready[p] = pos->next;
+    ready_count--;
+    current_priority = pos->priority;
+    current_lifeness = pos->lifeness;
+    active_task = pos;

 #if PROFILE_DELAYS
 #if PROFILE_DELAYS

-      if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value >
-         DELAY_THRESHOLD.rel_value)
-       {
-         GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                     "Task %llu took %llums to be scheduled\n",
-                     pos->id,
-                     (unsigned long long) GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value);
-       }
-#endif
-      tc.reason = pos->reason;
-      tc.read_ready = (pos->read_set == NULL) ? rs : pos->read_set; 
-      if ( (pos->read_fd != -1) &&
-          (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)) )
-       GNUNET_NETWORK_fdset_set_native (rs,
-                                        pos->read_fd);
-      tc.write_ready = (pos->write_set == NULL) ? ws : pos->write_set;
-      if ( (pos->write_fd != -1) &&
-          (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) )
-       GNUNET_NETWORK_fdset_set_native (ws,
-                                        pos->write_fd);
-      if ( ( (tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY) != 0) &&
-          (pos->write_fd != -1) &&
-          (! GNUNET_NETWORK_fdset_test_native (ws,
-                                               pos->write_fd))) 
-       abort (); // added to ready in previous select loop!
-#if DEBUG_TASKS
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Running task: %llu / %p\n", pos->id, pos->callback_cls);
+    if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
+        DELAY_THRESHOLD.rel_value_us)
+    {
+      LOG (GNUNET_ERROR_TYPE_DEBUG,
+          "Task %llu took %s to be scheduled\n",
+           (unsigned long long) pos->id,
+           GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
+                                                   GNUNET_YES));
+    }

 #endif
 #endif

-      pos->callback (pos->callback_cls, &tc);
+    tc.reason = pos->reason;
+    tc.read_ready = (pos->read_set == NULL) ? rs : pos->read_set;
+    if ((pos->read_fd != -1) &&
+        (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)))
+      GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
+    tc.write_ready = (pos->write_set == NULL) ? ws : pos->write_set;
+    if ((pos->write_fd != -1) &&
+        (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
+      GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
+    if (((tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY) != 0) &&
+        (pos->write_fd != -1) &&
+        (!GNUNET_NETWORK_fdset_test_native (ws, pos->write_fd)))
+      GNUNET_abort ();          // added to ready in previous select loop!
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+        "Running task: %llu / %p\n", pos->id,
+         pos->callback_cls);
+    pos->callback (pos->callback_cls, &tc);

 #if EXECINFO
 #if EXECINFO

-      int i;
-      for (i=0;i<pos->num_backtrace_strings;i++)
-        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                    "Task %llu trace %d: %s\n",
-                    pos->id,
-                    i,
-                    pos->backtrace_strings[i]);
+    int i;
+
+    for (i = 0; i < pos->num_backtrace_strings; i++)
+      LOG (GNUNET_ERROR_TYPE_ERROR,
+           "Task %llu trace %d: %s\n",
+           pos->id,
+           i,
+           pos->backtrace_strings[i]);

 #endif
 #endif

-      active_task = NULL;
-      destroy_task (pos);
-      tasks_run++;
-    }
-  while ( (pending == NULL) || (p >= max_priority_added) );
+    active_task = NULL;
+    destroy_task (pos);
+    tasks_run++;
+  }
+  while ((NULL == pending) || (p >= max_priority_added));

 }
 
 /**
 }
 
 /**


@@ -661,6 +615,12 @@ run_ready (struct GNUNET_NETWORK_FDSet *rs,
  */
 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
 
  */
 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
 

+/**
+ * Process ID of this process at the time we installed the various
+ * signal handlers.
+ */
+static pid_t my_pid;
+

 /**
  * Signal handler called for SIGPIPE.
  */
 /**
  * Signal handler called for SIGPIPE.
  */


@@ -671,6 +631,26 @@ sighandler_pipe ()
   return;
 }
 #endif
   return;
 }
 #endif

+
+
+/**
+ * Wait for a short time.
+ * Sleeps for @a ms ms (as that should be long enough for virtually all
+ * modern systems to context switch and allow another process to do
+ * some 'real' work).
+ *
+ * @param ms how many ms to wait
+ */
+static void
+short_wait (unsigned int ms)
+{
+  struct GNUNET_TIME_Relative timeout;
+
+  timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, ms);
+  (void) GNUNET_NETWORK_socket_select (NULL, NULL, NULL, timeout);
+}
+
+

 /**
  * Signal handler called for signals that should cause us to shutdown.
  */
 /**
  * Signal handler called for signals that should cause us to shutdown.
  */


@@ -678,28 +658,60 @@ static void
 sighandler_shutdown ()
 {
   static char c;
 sighandler_shutdown ()
 {
   static char c;

-  int old_errno = errno; /* backup errno */
+  int old_errno = errno;        /* backup errno */

 
 

+  if (getpid () != my_pid)
+    exit (1);                   /* we have fork'ed since the signal handler was created,
+                                 * ignore the signal, see https://gnunet.org/vfork discussion */

   GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle
   GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle

-                          (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE), &c,
-                          sizeof (c));
+                          (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE),
+                          &c, sizeof (c));

   errno = old_errno;
 }
 
 
   errno = old_errno;
 }
 
 

+/**
+ * Check if the system is still life. Trigger shutdown if we
+ * have tasks, but none of them give us lifeness.
+ *
+ * @return #GNUNET_OK to continue the main loop,
+ *         #GNUNET_NO to exit
+ */
+static int
+check_lifeness ()
+{
+  struct Task *t;
+
+  if (ready_count > 0)
+    return GNUNET_OK;
+  for (t = pending; NULL != t; t = t->next)
+    if (t->lifeness == GNUNET_YES)
+      return GNUNET_OK;
+  for (t = pending_timeout; NULL != t; t = t->next)
+    if (t->lifeness == GNUNET_YES)
+      return GNUNET_OK;
+  if ((NULL != pending) || (NULL != pending_timeout))
+  {
+    GNUNET_SCHEDULER_shutdown ();
+    return GNUNET_OK;
+  }
+  return GNUNET_NO;
+}
+
+

 /**
  * Initialize and run scheduler.  This function will return when all
  * tasks have completed.  On systems with signals, receiving a SIGTERM
 /**
  * Initialize and run scheduler.  This function will return when all
  * tasks have completed.  On systems with signals, receiving a SIGTERM

- * (and other similar signals) will cause "GNUNET_SCHEDULER_shutdown"
+ * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown()

  * to be run after the active task is complete.  As a result, SIGTERM
  * causes all active tasks to be scheduled with reason
  * to be run after the active task is complete.  As a result, SIGTERM
  * causes all active tasks to be scheduled with reason

- * "GNUNET_SCHEDULER_REASON_SHUTDOWN".  (However, tasks added
+ * #GNUNET_SCHEDULER_REASON_SHUTDOWN.  (However, tasks added

  * afterwards will execute normally!). Note that any particular signal
  * will only shut down one scheduler; applications should always only
  * create a single scheduler.
  *
  * @param task task to run immediately
  * afterwards will execute normally!). Note that any particular signal
  * will only shut down one scheduler; applications should always only
  * create a single scheduler.
  *
  * @param task task to run immediately

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  */
 void
 GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)
  */
 void
 GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)


@@ -710,6 +722,10 @@ GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)
   int ret;
   struct GNUNET_SIGNAL_Context *shc_int;
   struct GNUNET_SIGNAL_Context *shc_term;
   int ret;
   struct GNUNET_SIGNAL_Context *shc_int;
   struct GNUNET_SIGNAL_Context *shc_term;

+#if (SIGTERM != GNUNET_TERM_SIG)
+  struct GNUNET_SIGNAL_Context *shc_gterm;
+#endif
+

 #ifndef MINGW
   struct GNUNET_SIGNAL_Context *shc_quit;
   struct GNUNET_SIGNAL_Context *shc_hup;
 #ifndef MINGW
   struct GNUNET_SIGNAL_Context *shc_quit;
   struct GNUNET_SIGNAL_Context *shc_hup;


@@ -720,91 +736,108 @@ GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)
   const struct GNUNET_DISK_FileHandle *pr;
   char c;
 
   const struct GNUNET_DISK_FileHandle *pr;
   char c;
 

-  GNUNET_assert (active_task == NULL);
+  GNUNET_assert (NULL == active_task);

   rs = GNUNET_NETWORK_fdset_create ();
   ws = GNUNET_NETWORK_fdset_create ();
   rs = GNUNET_NETWORK_fdset_create ();
   ws = GNUNET_NETWORK_fdset_create ();

-  GNUNET_assert (shutdown_pipe_handle == NULL);
-  shutdown_pipe_handle =  GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, GNUNET_NO);
-  GNUNET_assert (shutdown_pipe_handle != NULL);
-  pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_READ);
+  GNUNET_assert (NULL == shutdown_pipe_handle);
+  shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, GNUNET_NO, GNUNET_NO);
+  GNUNET_assert (NULL != shutdown_pipe_handle);
+  pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
+                                GNUNET_DISK_PIPE_END_READ);

   GNUNET_assert (pr != NULL);
   GNUNET_assert (pr != NULL);

+  my_pid = getpid ();
+  LOG (GNUNET_ERROR_TYPE_DEBUG, "Registering signal handlers\n");

   shc_int = GNUNET_SIGNAL_handler_install (SIGINT, &sighandler_shutdown);
   shc_term = GNUNET_SIGNAL_handler_install (SIGTERM, &sighandler_shutdown);
   shc_int = GNUNET_SIGNAL_handler_install (SIGINT, &sighandler_shutdown);
   shc_term = GNUNET_SIGNAL_handler_install (SIGTERM, &sighandler_shutdown);

+#if (SIGTERM != GNUNET_TERM_SIG)
+  shc_gterm = GNUNET_SIGNAL_handler_install (GNUNET_TERM_SIG, &sighandler_shutdown);
+#endif

 #ifndef MINGW
   shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE, &sighandler_pipe);
   shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT, &sighandler_shutdown);
   shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP, &sighandler_shutdown);
 #endif
   current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
 #ifndef MINGW
   shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE, &sighandler_pipe);
   shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT, &sighandler_shutdown);
   shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP, &sighandler_shutdown);
 #endif
   current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;

-  GNUNET_SCHEDULER_add_continuation (task,
-                                     task_cls,
+  current_lifeness = GNUNET_YES;
+  GNUNET_SCHEDULER_add_continuation (task, task_cls,

                                      GNUNET_SCHEDULER_REASON_STARTUP);
                                      GNUNET_SCHEDULER_REASON_STARTUP);

-#if ENABLE_WINDOWS_WORKAROUNDS
-  GNUNET_SCHEDULER_add_continuation (&GNUNET_OS_install_parent_control_handler,
-                                     NULL, GNUNET_SCHEDULER_REASON_STARTUP);
-#endif
+  active_task = (void *) (long) -1;     /* force passing of sanity check */
+  GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
+                                          &GNUNET_OS_install_parent_control_handler,
+                                          NULL);
+  active_task = NULL;

   last_tr = 0;
   busy_wait_warning = 0;
   last_tr = 0;
   busy_wait_warning = 0;

-  while ((pending != NULL) ||
-        (pending_timeout != NULL) ||
-        (ready_count > 0))
+  while (GNUNET_OK == check_lifeness ())
+  {
+    GNUNET_NETWORK_fdset_zero (rs);
+    GNUNET_NETWORK_fdset_zero (ws);
+    timeout = GNUNET_TIME_UNIT_FOREVER_REL;
+    update_sets (rs, ws, &timeout);
+    GNUNET_NETWORK_fdset_handle_set (rs, pr);
+    if (ready_count > 0)

     {
     {

-      GNUNET_NETWORK_fdset_zero (rs);
-      GNUNET_NETWORK_fdset_zero (ws);
-      timeout = GNUNET_TIME_UNIT_FOREVER_REL;
-      update_sets (rs, ws, &timeout);
-      GNUNET_NETWORK_fdset_handle_set (rs, pr);
-      if (ready_count > 0)
-        {
-          /* no blocking, more work already ready! */
-          timeout = GNUNET_TIME_UNIT_ZERO;
-        }
+      /* no blocking, more work already ready! */
+      timeout = GNUNET_TIME_UNIT_ZERO;
+    }
+    if (NULL == scheduler_select)

       ret = GNUNET_NETWORK_socket_select (rs, ws, NULL, timeout);
       ret = GNUNET_NETWORK_socket_select (rs, ws, NULL, timeout);

-      if (ret == GNUNET_SYSERR)
-        {
-          if (errno == EINTR)
-            continue;
+    else
+      ret = scheduler_select (scheduler_select_cls, rs, ws, NULL, timeout);
+    if (ret == GNUNET_SYSERR)
+    {
+      if (errno == EINTR)
+        continue;

 
 

-          GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "select");
+      LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "select");

 #ifndef MINGW
 #if USE_LSOF
 #ifndef MINGW
 #if USE_LSOF

-         char lsof[512];
-         snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid());
-         close (1);
-         dup2 (2, 1);
-         ret = system (lsof);            
+      char lsof[512];
+
+      snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid ());
+      (void) close (1);
+      (void) dup2 (2, 1);
+      if (0 != system (lsof))
+        LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
+                      "system");

 #endif
 #endif
 #endif
 #endif

-          abort ();
-         break;
-        }
-      if ((ret == 0) && (timeout.rel_value == 0) && (busy_wait_warning > 16))
-        {
-          GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                      _("Looks like we're busy waiting...\n"));
-          sleep (1);            /* mitigate */
-        }
-      check_ready (rs, ws);
-      run_ready (rs, ws);
-      if (GNUNET_NETWORK_fdset_handle_isset (rs, pr))
-        {
-          /* consume the signal */
-          GNUNET_DISK_file_read (pr, &c, sizeof (c));
-          /* mark all active tasks as ready due to shutdown */
-          GNUNET_SCHEDULER_shutdown ();
-        }
-      if (last_tr == tasks_run)
-        {
-          busy_wait_warning++;
-        }
-      else
-        {
-          last_tr = tasks_run;
-          busy_wait_warning = 0;
-        }
+      GNUNET_abort ();
+      break;
+    }
+    if ( (0 == ret) &&
+         (0 == timeout.rel_value_us) &&
+         (busy_wait_warning > 16) )
+    {
+      LOG (GNUNET_ERROR_TYPE_WARNING,
+           _("Looks like we're busy waiting...\n"));
+      short_wait (100);                /* mitigate */
+    }
+    check_ready (rs, ws);
+    run_ready (rs, ws);
+    if (GNUNET_NETWORK_fdset_handle_isset (rs, pr))
+    {
+      /* consume the signal */
+      GNUNET_DISK_file_read (pr, &c, sizeof (c));
+      /* mark all active tasks as ready due to shutdown */
+      GNUNET_SCHEDULER_shutdown ();

     }
     }

+    if (last_tr == tasks_run)
+    {
+      short_wait (1);
+      busy_wait_warning++;
+    }
+    else
+    {
+      last_tr = tasks_run;
+      busy_wait_warning = 0;
+    }
+  }

   GNUNET_SIGNAL_handler_uninstall (shc_int);
   GNUNET_SIGNAL_handler_uninstall (shc_term);
   GNUNET_SIGNAL_handler_uninstall (shc_int);
   GNUNET_SIGNAL_handler_uninstall (shc_term);

+#if (SIGTERM != GNUNET_TERM_SIG)
+  GNUNET_SIGNAL_handler_uninstall (shc_gterm);
+#endif

 #ifndef MINGW
   GNUNET_SIGNAL_handler_uninstall (shc_pipe);
   GNUNET_SIGNAL_handler_uninstall (shc_quit);
 #ifndef MINGW
   GNUNET_SIGNAL_handler_uninstall (shc_pipe);
   GNUNET_SIGNAL_handler_uninstall (shc_quit);


@@ -819,8 +852,8 @@ GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)
 
 /**
  * Obtain the reason code for why the current task was
 
 /**
  * Obtain the reason code for why the current task was

- * started.  Will return the same value as 
- * the GNUNET_SCHEDULER_TaskContext's reason field.
+ * started.  Will return the same value as
+ * the `struct GNUNET_SCHEDULER_TaskContext`'s reason field.

  *
  * @return reason(s) why the current task is run
  */
  *
  * @return reason(s) why the current task is run
  */


@@ -854,11 +887,11 @@ GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p)
     p = current_priority;
   ret = 0;
   pos = ready[check_priority (p)];
     p = current_priority;
   ret = 0;
   pos = ready[check_priority (p)];

-  while (pos != NULL)
-    {
-      pos = pos->next;
-      ret++;
-    }
+  while (NULL != pos)
+  {
+    pos = pos->next;
+    ret++;
+  }

   return ret;
 }
 
   return ret;
 }
 


@@ -879,77 +912,83 @@ GNUNET_SCHEDULER_cancel (GNUNET_SCHEDULER_TaskIdentifier task)
   int to;
   void *ret;
 
   int to;
   void *ret;
 

-  GNUNET_assert (active_task != NULL);
+  GNUNET_assert (NULL != active_task);

   to = 0;
   prev = NULL;
   t = pending;
   to = 0;
   prev = NULL;
   t = pending;

-  while (t != NULL)
+  while (NULL != t)
+  {
+    if (t->id == task)
+      break;
+    prev = t;
+    t = t->next;
+  }
+  if (NULL == t)
+  {
+    prev = NULL;
+    to = 1;
+    t = pending_timeout;
+    while (t != NULL)

     {
       if (t->id == task)
         break;
       prev = t;
       t = t->next;
     }
     {
       if (t->id == task)
         break;
       prev = t;
       t = t->next;
     }

-  if (t == NULL)
+    if (pending_timeout_last == t)
+      pending_timeout_last = NULL;
+  }
+  p = 0;
+  while (NULL == t)
+  {
+    p++;
+    if (p >= GNUNET_SCHEDULER_PRIORITY_COUNT)

     {
     {

-      prev = NULL;
-      to = 1;
-      t = pending_timeout;
-      while (t != NULL)
-       {
-         if (t->id == task)
-           break;
-         prev = t;
-         t = t->next;
-       }
-      if (pending_timeout_last == t)
-       pending_timeout_last = NULL;
+      LOG (GNUNET_ERROR_TYPE_ERROR,
+           _("Attempt to cancel dead task %llu!\n"),
+           (unsigned long long) task);
+      GNUNET_assert (0);

     }
     }

-  p = 0;
-  while (t == NULL)
+    prev = NULL;
+    t = ready[p];
+    while (NULL != t)

     {
     {

-      p++;
-      GNUNET_assert (p < GNUNET_SCHEDULER_PRIORITY_COUNT);
-      prev = NULL;
-      t = ready[p];
-      while (t != NULL)
-        {
-          if (t->id == task)
-            {
-              ready_count--;
-              break;
-            }
-          prev = t;
-          t = t->next;
-        }
+      if (t->id == task)
+      {
+        ready_count--;
+        break;
+      }
+      prev = t;
+      t = t->next;

     }
     }

-  if (prev == NULL)
+  }
+  if (NULL == prev)
+  {
+    if (0 == p)

     {
     {

-      if (p == 0)
-       {
-         if (to == 0)
-           {
-             pending = t->next;
-           }
-         else
-           {
-             pending_timeout = t->next;
-           }
-       }
+      if (0 == to)
+      {
+        pending = t->next;
+      }

       else
       else

-       {
-         ready[p] = t->next;
-       }
+      {
+        pending_timeout = t->next;
+      }

     }
     }

-  else
+    else

     {
     {

-      prev->next = t->next;
+      ready[p] = t->next;

     }
     }

+  }
+  else
+  {
+    prev->next = t->next;
+  }

   ret = t->callback_cls;
   ret = t->callback_cls;

-#if DEBUG_TASKS
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Canceling task: %llu / %p\n", task, t->callback_cls);
-#endif
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Canceling task: %llu / %p\n",
+       task,
+       t->callback_cls);

   destroy_task (t);
   return ret;
 }
   destroy_task (t);
   return ret;
 }


@@ -961,25 +1000,29 @@ GNUNET_SCHEDULER_cancel (GNUNET_SCHEDULER_TaskIdentifier task)
  * and the reason code can be specified.
  *
  * @param task main function of the task
  * and the reason code can be specified.
  *
  * @param task main function of the task

- * @param task_cls closure for 'main'
+ * @param task_cls closure for @a task

  * @param reason reason for task invocation
  * @param reason reason for task invocation

+ * @param priority priority to use for the task

  */
 void
  */
 void

-GNUNET_SCHEDULER_add_continuation (GNUNET_SCHEDULER_Task task,
-                                   void *task_cls,
-                                   enum GNUNET_SCHEDULER_Reason reason)
+GNUNET_SCHEDULER_add_continuation_with_priority (GNUNET_SCHEDULER_Task task, void *task_cls,
+                                                enum GNUNET_SCHEDULER_Reason reason,
+                                                enum GNUNET_SCHEDULER_Priority priority)

 {
   struct Task *t;
 {
   struct Task *t;

+

 #if EXECINFO
   void *backtrace_array[50];
 #endif
 
 #if EXECINFO
   void *backtrace_array[50];
 #endif
 

-  GNUNET_assert ( (active_task != NULL) ||
-                 (reason == GNUNET_SCHEDULER_REASON_STARTUP) );
-  t = GNUNET_malloc (sizeof (struct Task));
+  GNUNET_assert (NULL != task);
+  GNUNET_assert ((NULL != active_task) ||
+                 (GNUNET_SCHEDULER_REASON_STARTUP == reason));
+  t = GNUNET_new (struct Task);

 #if EXECINFO
 #if EXECINFO

-  t->num_backtrace_strings = backtrace(backtrace_array, 50);
-  t->backtrace_strings = backtrace_symbols(backtrace_array, t->num_backtrace_strings);
+  t->num_backtrace_strings = backtrace (backtrace_array, 50);
+  t->backtrace_strings =
+      backtrace_symbols (backtrace_array, t->num_backtrace_strings);

 #endif
   t->read_fd = -1;
   t->write_fd = -1;
 #endif
   t->read_fd = -1;
   t->write_fd = -1;


@@ -990,41 +1033,32 @@ GNUNET_SCHEDULER_add_continuation (GNUNET_SCHEDULER_Task task,
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->reason = reason;
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->reason = reason;

-  t->priority = current_priority;
-#if DEBUG_TASKS
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Adding continuation task: %llu / %p\n",
-              t->id, t->callback_cls);
-#endif
+  t->priority = priority;
+  t->lifeness = current_lifeness;
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Adding continuation task: %llu / %p\n",
+       t->id,
+       t->callback_cls);

   queue_ready_task (t);
 }
 
 
   queue_ready_task (t);
 }
 
 

-

 /**
 /**

- * Schedule a new task to be run after the specified prerequisite task
- * has completed. It will be run with the priority of the calling
- * task.
+ * Continue the current execution with the given function.  This is
+ * similar to the other "add" functions except that there is no delay
+ * and the reason code can be specified.

  *
  *

- * @param prerequisite_task run this task after the task with the given
- *        task identifier completes (and any of our other
- *        conditions, such as delay, read or write-readiness
- *        are satisfied).  Use  GNUNET_SCHEDULER_NO_TASK to not have any dependency
- *        on completion of other tasks (this will cause the task to run as
- *        soon as possible).

  * @param task main function of the task
  * @param task main function of the task

- * @param task_cls closure of task
- * @return unique task identifier for the job
- *         only valid until "task" is started!
+ * @param task_cls closure for @a task
+ * @param reason reason for task invocation

  */
  */

-GNUNET_SCHEDULER_TaskIdentifier
-GNUNET_SCHEDULER_add_after (GNUNET_SCHEDULER_TaskIdentifier prerequisite_task,
-                            GNUNET_SCHEDULER_Task task, void *task_cls)
+void
+GNUNET_SCHEDULER_add_continuation (GNUNET_SCHEDULER_Task task, void *task_cls,
+                                   enum GNUNET_SCHEDULER_Reason reason)

 {
 {

-  return GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_KEEP,
-                                      prerequisite_task,
-                                      GNUNET_TIME_UNIT_ZERO,
-                                      NULL, NULL, task, task_cls);
+  GNUNET_SCHEDULER_add_continuation_with_priority (task, task_cls,
+                                                  reason,
+                                                  GNUNET_SCHEDULER_PRIORITY_DEFAULT);

 }
 
 
 }
 
 


@@ -1033,56 +1067,55 @@ GNUNET_SCHEDULER_add_after (GNUNET_SCHEDULER_TaskIdentifier prerequisite_task,
  *
  * @param prio how important is the new task?
  * @param task main function of the task
  *
  * @param prio how important is the new task?
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,

-                                    GNUNET_SCHEDULER_Task task,
-                                    void *task_cls)
+                                    GNUNET_SCHEDULER_Task task, void *task_cls)

 {
   return GNUNET_SCHEDULER_add_select (prio,
 {
   return GNUNET_SCHEDULER_add_select (prio,

-                                      GNUNET_SCHEDULER_NO_TASK,
-                                      GNUNET_TIME_UNIT_ZERO,
-                                      NULL, NULL, task, task_cls);
+                                      GNUNET_TIME_UNIT_ZERO, NULL, NULL, task,
+                                      task_cls);

 }
 
 
 
 /**
  * Schedule a new task to be run with a specified delay.  The task
 }
 
 
 
 /**
  * Schedule a new task to be run with a specified delay.  The task

- * will be scheduled for execution once the delay has expired. It
- * will be run with the priority of the calling task.
+ * will be scheduled for execution once the delay has expired.

  *
  *

- * @param delay when should this operation time out? Use 
- *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param priority priority to use for the task

  * @param task main function of the task
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
  */
 GNUNET_SCHEDULER_TaskIdentifier

-GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
-                              GNUNET_SCHEDULER_Task task, void *task_cls)
+GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay,
+                                           enum GNUNET_SCHEDULER_Priority priority,
+                                           GNUNET_SCHEDULER_Task task, void *task_cls)

 {
 {

-#if 1
-  /* new, optimized version */

   struct Task *t;
   struct Task *pos;
   struct Task *prev;
   struct Task *t;
   struct Task *pos;
   struct Task *prev;

+

 #if EXECINFO
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 
 #if EXECINFO
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 

-  GNUNET_assert (active_task != NULL);
+  GNUNET_assert (NULL != active_task);

   GNUNET_assert (NULL != task);
   GNUNET_assert (NULL != task);

-  t = GNUNET_malloc (sizeof (struct Task));
+  t = GNUNET_new (struct Task);

   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO
   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO

-  t->num_backtrace_strings = backtrace(backtrace_array, MAX_TRACE_DEPTH);
-  t->backtrace_strings = backtrace_symbols(backtrace_array, t->num_backtrace_strings);
+  t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
+  t->backtrace_strings =
+      backtrace_symbols (backtrace_array, t->num_backtrace_strings);

 #endif
   t->read_fd = -1;
   t->write_fd = -1;
 #endif
   t->read_fd = -1;
   t->write_fd = -1;


@@ -1091,29 +1124,30 @@ GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->timeout = GNUNET_TIME_relative_to_absolute (delay);
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->timeout = GNUNET_TIME_relative_to_absolute (delay);

-  t->priority = current_priority;
+  t->priority = priority;
+  t->lifeness = current_lifeness;

   /* try tail first (optimization in case we are
   /* try tail first (optimization in case we are

-     appending to a long list of tasks with timeouts) */
+   * appending to a long list of tasks with timeouts) */

   prev = pending_timeout_last;
   prev = pending_timeout_last;

-  if (prev != NULL) 
-    {
-      if (prev->timeout.abs_value > t->timeout.abs_value)
-       prev = NULL;
-      else
-       pos = prev->next; /* heuristic success! */
-    }
+  if (prev != NULL)
+  {
+    if (prev->timeout.abs_value_us > t->timeout.abs_value_us)
+      prev = NULL;
+    else
+      pos = prev->next;         /* heuristic success! */
+  }

   if (prev == NULL)
   if (prev == NULL)

-    {
-      /* heuristic failed, do traversal of timeout list */
-      pos = pending_timeout;
-    }
-  while ( (pos != NULL) &&
-         ( (pos->timeout.abs_value <= t->timeout.abs_value) ||
-           (pos->reason != 0) ) )
-    {
-      prev = pos;
-      pos = pos->next;
-    }
+  {
+    /* heuristic failed, do traversal of timeout list */
+    pos = pending_timeout;
+  }
+  while ((pos != NULL) &&
+         ((pos->timeout.abs_value_us <= t->timeout.abs_value_us) ||
+          (0 != pos->reason)))
+  {
+    prev = pos;
+    pos = pos->next;
+  }

   if (prev == NULL)
     pending_timeout = t;
   else
   if (prev == NULL)
     pending_timeout = t;
   else


@@ -1122,52 +1156,92 @@ GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
   /* hyper-optimization... */
   pending_timeout_last = t;
 
   /* hyper-optimization... */
   pending_timeout_last = t;
 

-#if DEBUG_TASKS
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Adding task: %llu / %p\n", t->id, t->callback_cls);
-#endif
+  LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id,
+       t->callback_cls);

 #if EXECINFO
   int i;
 
 #if EXECINFO
   int i;
 

-  for (i=0;i<t->num_backtrace_strings;i++)
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Task %llu trace %d: %s\n",
-                  t->id,
-                  i,
-                  t->backtrace_strings[i]);
+  for (i = 0; i < t->num_backtrace_strings; i++)
+    LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i,
+         t->backtrace_strings[i]);

 #endif
   return t->id;
 #endif
   return t->id;

-
-#else
-  /* unoptimized version */
-  return GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_KEEP,
-                                      GNUNET_SCHEDULER_NO_TASK, delay,
-                                      NULL, NULL, task, task_cls);
-#endif

 }
 
 
 }
 
 

-

 /**
 /**

- * Schedule a new task to be run as soon as possible. The task
- * will be run with the priority of the calling task.
+ * Schedule a new task to be run with a specified delay.  The task
+ * will be scheduled for execution once the delay has expired. It
+ * will be run with the DEFAULT priority.

  *
  *

+ * @param delay when should this operation time out? Use
+ *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"

  * @param task main function of the task
  * @param task_cls closure of task
  * @return unique task identifier for the job
  *         only valid until "task" is started!
  */
 GNUNET_SCHEDULER_TaskIdentifier
  * @param task main function of the task
  * @param task_cls closure of task
  * @return unique task identifier for the job
  *         only valid until "task" is started!
  */
 GNUNET_SCHEDULER_TaskIdentifier

-GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task,
-                                                 void *task_cls)
+GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
+                              GNUNET_SCHEDULER_Task task, void *task_cls)
+{
+  return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
+                                                    GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+                                                    task, task_cls);
+}
+
+
+/**
+ * Schedule a new task to be run as soon as possible.  Note that this
+ * does not guarantee that this will be the next task that is being
+ * run, as other tasks with higher priority (or that are already ready
+ * to run) might get to run first.  Just as with delays, clients must
+ * not rely on any particular order of execution between tasks
+ * scheduled concurrently.
+ *
+ * The task will be run with the DEFAULT priority.
+ *
+ * @param task main function of the task
+ * @param task_cls closure of @a task
+ * @return unique task identifier for the job
+ *         only valid until "task" is started!
+ */
+GNUNET_SCHEDULER_TaskIdentifier
+GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task, void *task_cls)

 {
 {

-  return GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_KEEP,
-                                      GNUNET_SCHEDULER_NO_TASK,
-                                     GNUNET_TIME_UNIT_ZERO,
-                                      NULL, NULL, task, task_cls);
+  return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO, task, task_cls);

 }
 
 
 }
 
 

+/**
+ * Schedule a new task to be run as soon as possible with the
+ * (transitive) ignore-shutdown flag either explicitly set or
+ * explicitly enabled.  This task (and all tasks created from it,
+ * other than by another call to this function) will either count or
+ * not count for the "lifeness" of the process.  This API is only
+ * useful in a few special cases.
+ *
+ * @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not.
+ * @param task main function of the task
+ * @param task_cls closure of @a task
+ * @return unique task identifier for the job
+ *         only valid until @a task is started!
+ */
+GNUNET_SCHEDULER_TaskIdentifier
+GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness,
+                                        GNUNET_SCHEDULER_Task task,
+                                        void *task_cls)
+{
+  GNUNET_SCHEDULER_TaskIdentifier ret;
+
+  ret =
+      GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+                                   GNUNET_TIME_UNIT_ZERO, NULL, NULL, task,
+                                   task_cls);
+  GNUNET_assert (pending->id == ret);
+  pending->lifeness = lifeness;
+  return ret;
+}

 
 
 /**
 
 
 /**


@@ -1187,62 +1261,107 @@ GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task,
  *     || shutdown-active )
  * </code>
  *
  *     || shutdown-active )
  * </code>
  *

- * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever",
+ * @param delay how long should we wait? Use #GNUNET_TIME_UNIT_FOREVER_REL for "forever",

  *        which means that the task will only be run after we receive SIGTERM
  *        which means that the task will only be run after we receive SIGTERM

+ * @param priority priority to use

  * @param rfd file descriptor we want to read (can be -1)
  * @param wfd file descriptors we want to write (can be -1)
  * @param task main function of the task
  * @param rfd file descriptor we want to read (can be -1)
  * @param wfd file descriptors we want to write (can be -1)
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  *         only valid until "task" is started!
  */
 #ifndef MINGW
  * @return unique task identifier for the job
  *         only valid until "task" is started!
  */
 #ifndef MINGW

-GNUNET_SCHEDULER_TaskIdentifier
+static GNUNET_SCHEDULER_TaskIdentifier

 add_without_sets (struct GNUNET_TIME_Relative delay,
 add_without_sets (struct GNUNET_TIME_Relative delay,

-                 int rfd,
-                 int wfd,
-                 GNUNET_SCHEDULER_Task task, void *task_cls)
+                 enum GNUNET_SCHEDULER_Priority priority,
+                 int rfd, int wfd,
+                  GNUNET_SCHEDULER_Task task, void *task_cls)

 {
   struct Task *t;
 {
   struct Task *t;

+

 #if EXECINFO
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 
 #if EXECINFO
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 

-  GNUNET_assert (active_task != NULL);
+  GNUNET_assert (NULL != active_task);

   GNUNET_assert (NULL != task);
   GNUNET_assert (NULL != task);

-  t = GNUNET_malloc (sizeof (struct Task));
+  t = GNUNET_new (struct Task);

   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO
   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO

-  t->num_backtrace_strings = backtrace(backtrace_array, MAX_TRACE_DEPTH);
-  t->backtrace_strings = backtrace_symbols(backtrace_array, t->num_backtrace_strings);
+  t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
+  t->backtrace_strings =
+      backtrace_symbols (backtrace_array, t->num_backtrace_strings);
+#endif
+#if DEBUG_FDS
+  if (-1 != rfd)
+  {
+    int flags = fcntl (rfd, F_GETFD);
+
+    if ((flags == -1) && (errno == EBADF))
+    {
+      LOG (GNUNET_ERROR_TYPE_ERROR,
+           "Got invalid file descriptor %d!\n",
+           rfd);
+#if EXECINFO
+      int i;
+
+      for (i = 0; i < t->num_backtrace_strings; i++)
+        LOG (GNUNET_ERROR_TYPE_DEBUG,
+             "Trace: %s\n",
+             t->backtrace_strings[i]);
+#endif
+      GNUNET_assert (0);
+    }
+  }
+  if (-1 != wfd)
+  {
+    int flags = fcntl (wfd, F_GETFD);
+
+    if (flags == -1 && errno == EBADF)
+    {
+      LOG (GNUNET_ERROR_TYPE_ERROR,
+           "Got invalid file descriptor %d!\n",
+           wfd);
+#if EXECINFO
+      int i;
+
+      for (i = 0; i < t->num_backtrace_strings; i++)
+        LOG (GNUNET_ERROR_TYPE_DEBUG,
+             "Trace: %s\n",
+             t->backtrace_strings[i]);
+#endif
+      GNUNET_assert (0);
+    }
+  }

 #endif
   t->read_fd = rfd;
 #endif
   t->read_fd = rfd;

+  GNUNET_assert (wfd >= -1);

   t->write_fd = wfd;
   t->id = ++last_id;
 #if PROFILE_DELAYS
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->write_fd = wfd;
   t->id = ++last_id;
 #if PROFILE_DELAYS
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif

-  t->prereq_id = GNUNET_SCHEDULER_NO_TASK;

   t->timeout = GNUNET_TIME_relative_to_absolute (delay);
   t->timeout = GNUNET_TIME_relative_to_absolute (delay);

-  t->priority = check_priority (current_priority);
+  t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority);
+  t->lifeness = current_lifeness;

   t->next = pending;
   pending = t;
   t->next = pending;
   pending = t;

-  max_priority_added = GNUNET_MAX (max_priority_added,
-                                         t->priority);
-#if DEBUG_TASKS
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Adding task: %llu / %p\n", t->id, t->callback_cls);
-#endif
+  max_priority_added = GNUNET_MAX (max_priority_added, t->priority);
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Adding task: %llu / %p\n",
+       t->id,
+       t->callback_cls);

 #if EXECINFO
   int i;
 
 #if EXECINFO
   int i;
 

-  for (i=0;i<t->num_backtrace_strings;i++)
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Task %llu trace %d: %s\n",
-                  t->id,
-                  i,
-                  t->backtrace_strings[i]);
+  for (i = 0; i < t->num_backtrace_strings; i++)
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Task %llu trace %d: %s\n",
+         t->id,
+         i,
+         t->backtrace_strings[i]);

 #endif
   return t->id;
 }
 #endif
   return t->id;
 }


@@ -1255,41 +1374,54 @@ add_without_sets (struct GNUNET_TIME_Relative delay,
  * specified file descriptor is ready for reading.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the
  * specified file descriptor is ready for reading.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the

- * socket operation is ready.  It will be run with the priority of
- * the calling task.
+ * socket operation is ready.  It will be run with the DEFAULT priority.

  *
  *

- * @param delay when should this operation time out? Use 
- *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"

  * @param rfd read file-descriptor
  * @param task main function of the task
  * @param rfd read file-descriptor
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,

-                               struct GNUNET_NETWORK_Handle * rfd,
+                               struct GNUNET_NETWORK_Handle *rfd,

                                GNUNET_SCHEDULER_Task task, void *task_cls)
 {
                                GNUNET_SCHEDULER_Task task, void *task_cls)
 {

-#if MINGW
-  struct GNUNET_NETWORK_FDSet *rs;
-  GNUNET_SCHEDULER_TaskIdentifier ret;
+  return GNUNET_SCHEDULER_add_read_net_with_priority (delay,
+                                                     GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+                                                     rfd, task, task_cls);
+}

 
 

-  GNUNET_assert (rfd != NULL);
-  rs = GNUNET_NETWORK_fdset_create ();
-  GNUNET_NETWORK_fdset_set (rs, rfd);
-  ret = GNUNET_SCHEDULER_add_select (check_priority (current_priority),
-                                     GNUNET_SCHEDULER_NO_TASK, delay,
-                                     rs, NULL, task, task_cls);
-  GNUNET_NETWORK_fdset_destroy (rs);
-  return ret;
-#else
-  return add_without_sets (delay,
-                          GNUNET_NETWORK_get_fd (rfd),
-                          -1,
-                          task,
-                          task_cls);
-#endif
+
+/**
+ * Schedule a new task to be run with a specified priority and to be
+ * run after the specified delay or when the specified file descriptor
+ * is ready for reading.  The delay can be used as a timeout on the
+ * socket being ready.  The task will be scheduled for execution once
+ * either the delay has expired or the socket operation is ready.  It
+ * will be run with the DEFAULT priority.
+ *
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param priority priority to use for the task
+ * @param rfd read file-descriptor
+ * @param task main function of the task
+ * @param task_cls closure of @a task
+ * @return unique task identifier for the job
+ *         only valid until @a task is started!
+ */
+GNUNET_SCHEDULER_TaskIdentifier
+GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay,
+                                            enum GNUNET_SCHEDULER_Priority priority,
+                                            struct GNUNET_NETWORK_Handle *rfd,
+                                            GNUNET_SCHEDULER_Task task, void *task_cls)
+{
+  return GNUNET_SCHEDULER_add_net_with_priority (
+      delay, priority,
+      rfd, GNUNET_YES, GNUNET_NO,
+      task, task_cls);

 }
 
 
 }
 
 


@@ -1301,37 +1433,71 @@ GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
  * socket operation is ready.  It will be run with the priority of
  * the calling task.
  *
  * socket operation is ready.  It will be run with the priority of
  * the calling task.
  *

- * @param delay when should this operation time out? Use 
- *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"

  * @param wfd write file-descriptor
  * @param task main function of the task
  * @param wfd write file-descriptor
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,

-                                struct GNUNET_NETWORK_Handle * wfd,
+                                struct GNUNET_NETWORK_Handle *wfd,

                                 GNUNET_SCHEDULER_Task task, void *task_cls)
                                 GNUNET_SCHEDULER_Task task, void *task_cls)

+{
+  return GNUNET_SCHEDULER_add_net_with_priority (
+      delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+      wfd, GNUNET_NO, GNUNET_YES,
+      task, task_cls);
+}
+
+/**
+ * Schedule a new task to be run with a specified delay or when the
+ * specified file descriptor is ready.  The delay can be
+ * used as a timeout on the socket being ready.  The task will be
+ * scheduled for execution once either the delay has expired or the
+ * socket operation is ready.
+ *
+ * @param delay when should this operation time out? Use
+ *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param priority priority of the task
+ * @param fd file-descriptor
+ * @param on_read whether to poll the file-descriptor for readability
+ * @param on_write whether to poll the file-descriptor for writability
+ * @param task main function of the task
+ * @param task_cls closure of task
+ * @return unique task identifier for the job
+ *         only valid until "task" is started!
+ */
+GNUNET_SCHEDULER_TaskIdentifier
+GNUNET_SCHEDULER_add_net_with_priority  (struct GNUNET_TIME_Relative delay,
+                                         enum GNUNET_SCHEDULER_Priority priority,
+                                         struct GNUNET_NETWORK_Handle *fd,
+                                         int on_read, int on_write,
+                                         GNUNET_SCHEDULER_Task task, void *task_cls)

 {
 #if MINGW
 {
 #if MINGW

-  struct GNUNET_NETWORK_FDSet *ws;
+  struct GNUNET_NETWORK_FDSet *s;

   GNUNET_SCHEDULER_TaskIdentifier ret;
 
   GNUNET_SCHEDULER_TaskIdentifier ret;
 

-  GNUNET_assert (wfd != NULL);
-  ws = GNUNET_NETWORK_fdset_create ();
-  GNUNET_NETWORK_fdset_set (ws, wfd);
-  ret = GNUNET_SCHEDULER_add_select (check_priority (current_priority),
-                                     GNUNET_SCHEDULER_NO_TASK, delay,
-                                     NULL, ws, task, task_cls);
-  GNUNET_NETWORK_fdset_destroy (ws);
+  GNUNET_assert (fd != NULL);
+  s = GNUNET_NETWORK_fdset_create ();
+  GNUNET_NETWORK_fdset_set (s, fd);
+  ret = GNUNET_SCHEDULER_add_select (
+      priority, delay,
+      on_read  ? s : NULL,
+      on_write ? s : NULL,
+      task, task_cls);
+  GNUNET_NETWORK_fdset_destroy (s);

   return ret;
 #else
   return ret;
 #else

-  return add_without_sets (delay,
-                          -1,
-                          GNUNET_NETWORK_get_fd (wfd),
-                          task,
-                          task_cls);
+  GNUNET_assert (GNUNET_NETWORK_get_fd (fd) >= 0);
+  return add_without_sets (
+      delay, priority,
+      on_read  ? GNUNET_NETWORK_get_fd (fd) : -1,
+      on_write ? GNUNET_NETWORK_get_fd (fd) : -1,
+      task, task_cls);

 #endif
 }
 
 #endif
 }
 


@@ -1341,45 +1507,25 @@ GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
  * specified file descriptor is ready for reading.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the
  * specified file descriptor is ready for reading.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the

- * socket operation is ready. It will be run with the priority of
- * the calling task.
+ * socket operation is ready. It will be run with the DEFAULT priority.

  *
  *

- * @param delay when should this operation time out? Use 
- *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"

  * @param rfd read file-descriptor
  * @param task main function of the task
  * @param rfd read file-descriptor
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,

-                                const struct GNUNET_DISK_FileHandle * rfd,
+                                const struct GNUNET_DISK_FileHandle *rfd,

                                 GNUNET_SCHEDULER_Task task, void *task_cls)
 {
                                 GNUNET_SCHEDULER_Task task, void *task_cls)
 {

-#if MINGW
-  struct GNUNET_NETWORK_FDSet *rs;
-  GNUNET_SCHEDULER_TaskIdentifier ret;
-
-  GNUNET_assert (rfd != NULL);
-  rs = GNUNET_NETWORK_fdset_create ();
-  GNUNET_NETWORK_fdset_handle_set (rs, rfd);
-  ret = GNUNET_SCHEDULER_add_select (check_priority (current_priority),
-                                     GNUNET_SCHEDULER_NO_TASK, delay,
-                                     rs, NULL, task, task_cls);
-  GNUNET_NETWORK_fdset_destroy (rs);
-  return ret;
-#else
-  int fd;
-
-  GNUNET_DISK_internal_file_handle_ (rfd, &fd, sizeof (int));
-  return add_without_sets (delay,
-                          fd,
-                          -1,
-                          task,
-                          task_cls);
-
-#endif
+  return GNUNET_SCHEDULER_add_file_with_priority (
+      delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+      rfd, GNUNET_YES, GNUNET_NO,
+      task, task_cls);

 }
 
 
 }
 
 


@@ -1388,49 +1534,81 @@ GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
  * specified file descriptor is ready for writing.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the
  * specified file descriptor is ready for writing.  The delay can be
  * used as a timeout on the socket being ready.  The task will be
  * scheduled for execution once either the delay has expired or the

- * socket operation is ready. It will be run with the priority of
- * the calling task.
+ * socket operation is ready. It will be run with the DEFAULT priority.

  *
  *

- * @param delay when should this operation time out? Use 
- *        GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"

  * @param wfd write file-descriptor
  * @param task main function of the task
  * @param wfd write file-descriptor
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,

-                                 const struct GNUNET_DISK_FileHandle * wfd,
+                                 const struct GNUNET_DISK_FileHandle *wfd,

                                  GNUNET_SCHEDULER_Task task, void *task_cls)
                                  GNUNET_SCHEDULER_Task task, void *task_cls)

+{
+  return GNUNET_SCHEDULER_add_file_with_priority (
+      delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+      wfd, GNUNET_NO, GNUNET_YES,
+      task, task_cls);
+}
+
+
+/**
+ * Schedule a new task to be run with a specified delay or when the
+ * specified file descriptor is ready.  The delay can be
+ * used as a timeout on the socket being ready.  The task will be
+ * scheduled for execution once either the delay has expired or the
+ * socket operation is ready.
+ *
+ * @param delay when should this operation time out? Use
+ *        #GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
+ * @param priority priority of the task
+ * @param fd file-descriptor
+ * @param on_read whether to poll the file-descriptor for readability
+ * @param on_write whether to poll the file-descriptor for writability
+ * @param task main function of the task
+ * @param task_cls closure of @a task
+ * @return unique task identifier for the job
+ *         only valid until @a task is started!
+ */
+GNUNET_SCHEDULER_TaskIdentifier
+GNUNET_SCHEDULER_add_file_with_priority (struct GNUNET_TIME_Relative delay,
+                                         enum GNUNET_SCHEDULER_Priority priority,
+                                         const struct GNUNET_DISK_FileHandle *fd,
+                                         int on_read, int on_write,
+                                         GNUNET_SCHEDULER_Task task, void *task_cls)

 {
 #if MINGW
 {
 #if MINGW

-  struct GNUNET_NETWORK_FDSet *ws;
+  struct GNUNET_NETWORK_FDSet *s;

   GNUNET_SCHEDULER_TaskIdentifier ret;
 
   GNUNET_SCHEDULER_TaskIdentifier ret;
 

-  GNUNET_assert (wfd != NULL);
-  ws = GNUNET_NETWORK_fdset_create ();
-  GNUNET_NETWORK_fdset_handle_set (ws, wfd);
-  ret = GNUNET_SCHEDULER_add_select (check_priority (current_priority),
-                                     GNUNET_SCHEDULER_NO_TASK,
-                                     delay, NULL, ws, task, task_cls);
-  GNUNET_NETWORK_fdset_destroy (ws);
+  GNUNET_assert (fd != NULL);
+  s = GNUNET_NETWORK_fdset_create ();
+  GNUNET_NETWORK_fdset_handle_set (s, fd);
+  ret = GNUNET_SCHEDULER_add_select (
+      priority, delay,
+      on_read  ? s : NULL,
+      on_write ? s : NULL,
+      task, task_cls);
+  GNUNET_NETWORK_fdset_destroy (s);

   return ret;
 #else
   return ret;
 #else

-  int fd;
-
-  GNUNET_DISK_internal_file_handle_ (wfd, &fd, sizeof (int));
-  return add_without_sets (delay,
-                          -1,
-                          fd,
-                          task,
-                          task_cls);
-
+  int real_fd;
+
+  GNUNET_DISK_internal_file_handle_ (fd, &real_fd, sizeof (int));
+  GNUNET_assert (real_fd >= 0);
+  return add_without_sets (
+      delay, priority,
+      on_read  ? real_fd : -1,
+      on_write ? real_fd : -1,
+      task, task_cls);

 #endif
 }
 
 
 #endif
 }
 
 

-

 /**
  * Schedule a new task to be run with a specified delay or when any of
  * the specified file descriptor sets is ready.  The delay can be used
 /**
  * Schedule a new task to be run with a specified delay or when any of
  * the specified file descriptor sets is ready.  The delay can be used


@@ -1449,27 +1627,20 @@ GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
  * </code>
  *
  * @param prio how important is this task?
  * </code>
  *
  * @param prio how important is this task?

- * @param prerequisite_task run this task after the task with the given
- *        task identifier completes (and any of our other
- *        conditions, such as delay, read or write-readiness
- *        are satisfied).  Use GNUNET_SCHEDULER_NO_TASK to not have any dependency
- *        on completion of other tasks.
- * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever",
+ * @param delay how long should we wait? Use #GNUNET_TIME_UNIT_FOREVER_REL for "forever",

  *        which means that the task will only be run after we receive SIGTERM
  * @param rs set of file descriptors we want to read (can be NULL)
  * @param ws set of file descriptors we want to write (can be NULL)
  * @param task main function of the task
  *        which means that the task will only be run after we receive SIGTERM
  * @param rs set of file descriptors we want to read (can be NULL)
  * @param ws set of file descriptors we want to write (can be NULL)
  * @param task main function of the task

- * @param task_cls closure of task
+ * @param task_cls closure of @a task

  * @return unique task identifier for the job
  * @return unique task identifier for the job

- *         only valid until "task" is started!
+ *         only valid until @a task is started!

  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
  */
 GNUNET_SCHEDULER_TaskIdentifier
 GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,

-                             GNUNET_SCHEDULER_TaskIdentifier
-                             prerequisite_task,

                              struct GNUNET_TIME_Relative delay,
                              struct GNUNET_TIME_Relative delay,

-                             const struct GNUNET_NETWORK_FDSet * rs,
-                             const struct GNUNET_NETWORK_FDSet * ws,
+                             const struct GNUNET_NETWORK_FDSet *rs,
+                             const struct GNUNET_NETWORK_FDSet *ws,

                              GNUNET_SCHEDULER_Task task, void *task_cls)
 {
   struct Task *t;
                              GNUNET_SCHEDULER_Task task, void *task_cls)
 {
   struct Task *t;


@@ -1477,54 +1648,53 @@ GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 
   void *backtrace_array[MAX_TRACE_DEPTH];
 #endif
 

-  GNUNET_assert (active_task != NULL);
+  GNUNET_assert (NULL != active_task);

   GNUNET_assert (NULL != task);
   GNUNET_assert (NULL != task);

-  t = GNUNET_malloc (sizeof (struct Task));
+  t = GNUNET_new (struct Task);

   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO
   t->callback = task;
   t->callback_cls = task_cls;
 #if EXECINFO

-  t->num_backtrace_strings = backtrace(backtrace_array, MAX_TRACE_DEPTH);
-  t->backtrace_strings = backtrace_symbols(backtrace_array, t->num_backtrace_strings);
+  t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
+  t->backtrace_strings =
+      backtrace_symbols (backtrace_array, t->num_backtrace_strings);

 #endif
   t->read_fd = -1;
   t->write_fd = -1;
 #endif
   t->read_fd = -1;
   t->write_fd = -1;

-  if (rs != NULL)
-    {
-      t->read_set = GNUNET_NETWORK_fdset_create ();
-      GNUNET_NETWORK_fdset_copy (t->read_set, rs);
-    }
-  if (ws != NULL)
-    {
-      t->write_set = GNUNET_NETWORK_fdset_create ();
-      GNUNET_NETWORK_fdset_copy (t->write_set, ws);
-    }
+  if (NULL != rs)
+  {
+    t->read_set = GNUNET_NETWORK_fdset_create ();
+    GNUNET_NETWORK_fdset_copy (t->read_set, rs);
+  }
+  if (NULL != ws)
+  {
+    t->write_set = GNUNET_NETWORK_fdset_create ();
+    GNUNET_NETWORK_fdset_copy (t->write_set, ws);
+  }

   t->id = ++last_id;
 #if PROFILE_DELAYS
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif
   t->id = ++last_id;
 #if PROFILE_DELAYS
   t->start_time = GNUNET_TIME_absolute_get ();
 #endif

-  t->prereq_id = prerequisite_task;

   t->timeout = GNUNET_TIME_relative_to_absolute (delay);
   t->priority =
   t->timeout = GNUNET_TIME_relative_to_absolute (delay);
   t->priority =

-    check_priority ((prio ==
-                     GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority
-                    : prio);
+      check_priority ((prio ==
+                       GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority :
+                      prio);
+  t->lifeness = current_lifeness;

   t->next = pending;
   pending = t;
   t->next = pending;
   pending = t;

-  max_priority_added = GNUNET_MAX (max_priority_added,
-                                         t->priority);
-#if DEBUG_TASKS
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Adding task: %llu / %p\n", t->id, t->callback_cls);
-#endif
+  max_priority_added = GNUNET_MAX (max_priority_added, t->priority);
+  LOG (GNUNET_ERROR_TYPE_DEBUG,
+       "Adding task: %llu / %p\n",
+       t->id,
+       t->callback_cls);

 #if EXECINFO
   int i;
 
 #if EXECINFO
   int i;
 

-  for (i=0;i<t->num_backtrace_strings;i++)
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                  "Task %llu trace %d: %s\n",
-                  t->id,
-                  i,
-                  t->backtrace_strings[i]);
+  for (i = 0; i < t->num_backtrace_strings; i++)
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Task %llu trace %d: %s\n",
+         t->id, i,
+         t->backtrace_strings[i]);

 #endif
   return t->id;
 }
 #endif
   return t->id;
 }