From 8f09ec61f8d24fcd4ad4a4438be4d90300d55175 Mon Sep 17 00:00:00 2001
From: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Wed, 30 Oct 2013 23:08:12 +0100
Subject: [PATCH 1/2] Add instant autoreload on platforms supporting kqueue.

---
 django/utils/autoreload.py | 45 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/django/utils/autoreload.py b/django/utils/autoreload.py
index ba98530f1b..9acd52e6e8 100644
--- a/django/utils/autoreload.py
+++ b/django/utils/autoreload.py
@@ -65,6 +65,16 @@ try:
 except ImportError:
     pass
 
+try:
+    import select
+    select.kevent, select.kqueue
+    USE_KQUEUE = True
+
+    import resource
+    NOFILES_SOFT, NOFILES_HARD = resource.getrlimit(resource.RLIMIT_NOFILE)
+except AttributeError:
+    USE_KQUEUE = False
+
 RUN_RELOADER = True
 
 _mtimes = {}
@@ -119,6 +129,39 @@ def inotify_code_changed():
     # If we are here the code must have changed.
     return True
 
+def kqueue_code_changed():
+    """
+    Checks for changed code using kqueue. After being called
+    it blocks until a change event has been fired.
+    """
+    # Maximum number of open file descriptors is typically too low (256).
+    filenames = list(gen_filenames())
+    resource.setrlimit(resource.RLIMIT_NOFILE,
+                       (NOFILES_SOFT + len(filenames), NOFILES_HARD))
+
+    kqueue = select.kqueue()
+    fds = [open(filename) for filename in filenames]
+
+    _filter = select.KQ_FILTER_VNODE
+    flags = select.KQ_EV_ADD
+    fflags = (
+        select.KQ_NOTE_DELETE |
+        select.KQ_NOTE_WRITE |
+        select.KQ_NOTE_EXTEND |
+        select.KQ_NOTE_ATTRIB |
+        select.KQ_NOTE_LINK |
+        select.KQ_NOTE_RENAME |
+        select.KQ_NOTE_REVOKE
+    )
+    kevents = [select.kevent(fd, _filter, flags, fflags) for fd in fds]
+    kqueue.control(kevents, 1)
+
+    for fd in fds:
+        fd.close()
+    kqueue.close()
+
+    return True
+
 def code_changed():
     global _mtimes, _win
     for filename in gen_filenames():
@@ -178,6 +221,8 @@ def reloader_thread():
     ensure_echo_on()
     if USE_INOTIFY:
         fn = inotify_code_changed
+    elif USE_KQUEUE:
+        fn = kqueue_code_changed
     else:
         fn = code_changed
     while RUN_RELOADER:

From 47217f2f290264b0467a079492779cbf3cbfa4f0 Mon Sep 17 00:00:00 2001
From: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Thu, 31 Oct 2013 10:15:42 +0100
Subject: [PATCH 2/2] Reduce the set of events that trigger a reload.

This seems to avoid multiple reloads.
---
 django/utils/autoreload.py | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/django/utils/autoreload.py b/django/utils/autoreload.py
index 9acd52e6e8..6816403cc7 100644
--- a/django/utils/autoreload.py
+++ b/django/utils/autoreload.py
@@ -144,15 +144,7 @@ def kqueue_code_changed():
 
     _filter = select.KQ_FILTER_VNODE
     flags = select.KQ_EV_ADD
-    fflags = (
-        select.KQ_NOTE_DELETE |
-        select.KQ_NOTE_WRITE |
-        select.KQ_NOTE_EXTEND |
-        select.KQ_NOTE_ATTRIB |
-        select.KQ_NOTE_LINK |
-        select.KQ_NOTE_RENAME |
-        select.KQ_NOTE_REVOKE
-    )
+    fflags = select.KQ_NOTE_DELETE | select.KQ_NOTE_WRITE | select.KQ_NOTE_RENAME
     kevents = [select.kevent(fd, _filter, flags, fflags) for fd in fds]
     kqueue.control(kevents, 1)