Backport kqueue integration from master

* configure.ac (--with-file-notification): Add kqueue.
(top): Remove special test for "${HAVE_NS}" and
${with_file_notification}, this is handled inside gfilenotify
tests.  Add kqueue tests.  Use NOTIFY_CFLAGS and NOTIFY_LIBS
instead of library specific variables.  Add error message for
gfile on Nextstep.

* doc/lispref/os.texi (File Notifications): Add kqueue as backend.
Fix some glitches in the example.

* etc/NEWS: Mention kqueue.

* lisp/filenotify.el (file-notify--library)
(file-notify-descriptors, file-notify-callback)
(file-notify-add-watch, file-notify-rm-watch)
(file-notify-valid-p): Add kqueue support.
(file-notify--rm-descriptor): Remove WHAT arg.

* src/Makefile.in: Use NOTIFY_CFLAGS and NOTIFY_LIBS.

* src/emacs.c (main): Call globals_of_kqueue and syms_of_kqueue.

* src/inotify.c (inotifyevent_to_event): Extract file name from
watch_object if the event doesn't provide it.
(Finotify_add_watch): Add file name to watch_object.

* src/keyboard.c (make_lispy_event): Check also for HAVE_KQUEUE.

* src/kqueue.c: New file.

* src/lisp.h: Declare extern globals_of_kqueue and syms_of_kqueue.

* test/automated/file-notify-tests.el
(file-notify--test-expected-events): Remove.
(file-notify--test-cleanup): Do not set that variable.
(file-notify--test-timeout) Use different timeouts for
different libraries.
(file-notify--test-library): New defun.
(file-notify--test-event-test): Make stronger checks.
(file-notify--test-with-events): EVENTS can also be a list of
lists.  Flush outstanding events before running the body.
Make timeout heuristically depend on the number of events.
(file-notify-test01-add-watch, file-notify-test02-events)
(file-notify-test04-file-validity, file-notify-test05-dir-validity):
Rewrite in order to call file monitors but directory monitors.
(file-notify-test02-events, file-notify-test04-file-validity): Do
not skip cygwin tests.  Add additional test for file creation.
Adapt expected result for different backends.
(file-notify-test03-autorevert): Some of the tests don't work for
w32notify.
(file-notify-test06-many-events): New test.

1 files changed, 22 insertions, 19 deletions

diff --git a/doc/lispref/os.texi b/doc/lispref/os.texi
index 7206cd4ef86..8e3720eb947 100644
--- a/doc/lispref/os.texi
+++ b/doc/lispref/os.texi
@@ -2653,9 +2653,9 @@ This function removes the tray notification given by its unique
 
 Several operating systems support watching of filesystems for changes
 of files.  If configured properly, Emacs links a respective library
-like @file{gfilenotify}, @file{inotify}, or @file{w32notify}
-statically.  These libraries enable watching of filesystems on the
-local machine.
+like @file{inotify}, @file{kqueue}, @file{gfilenotify}, or
+@file{w32notify} statically.  These libraries enable watching of
+filesystems on the local machine.
 
 It is also possible to watch filesystems on remote machines,
 @pxref{Remote Files,, Remote Files, emacs, The GNU Emacs Manual}
@@ -2726,7 +2726,8 @@ watching @var{file} has been stopped
 Note that the @file{w32notify} library does not report
 @code{attribute-changed} events.  When some file's attribute, like
 permissions or modification time, has changed, this library reports a
-@code{changed} event.
+@code{changed} event.  Likewise, the @file{kqueue} library does not
+report reliably file attribute changes when watching a directory.
 
 The @code{stopped} event reports, that watching the file has been
 stopped.  This could be because @code{file-notify-rm-watch} was called
@@ -2765,7 +2766,7 @@ being reported.  For example:
 @group
 (write-region "bla" nil "/tmp/foo")
      @result{} Event (35025468 created "/tmp/.#foo")
-        Event (35025468 changed "/tmp/foo") [2 times]
+        Event (35025468 changed "/tmp/foo")
         Event (35025468 deleted "/tmp/.#foo")
 @end group
 
@@ -2811,14 +2812,14 @@ also makes it invalid.
 @example
 @group
 (make-directory "/tmp/foo")
-     @result{} nil
+     @result{} Event (35025468 created "/tmp/foo")
 @end group
 
 @group
 (setq desc
       (file-notify-add-watch
         "/tmp/foo" '(change) 'my-notify-callback))
-     @result{} 35025468
+     @result{} 11359632
 @end group
 
 @group
@@ -2828,32 +2829,34 @@ also makes it invalid.
 
 @group
 (write-region "bla" nil "/tmp/foo/bla")
-     @result{} Event (35025468 created "/tmp/foo/.#bla")
-        Event (35025468 created "/tmp/foo/bla")
-        Event (35025468 changed "/tmp/foo/bla")
-        Event (35025468 changed "/tmp/foo/.#bla")
+     @result{} Event (11359632 created "/tmp/foo/.#bla")
+        Event (11359632 created "/tmp/foo/bla")
+        Event (11359632 changed "/tmp/foo/bla")
+        Event (11359632 deleted "/tmp/foo/.#bla")
 @end group
 
 @group
 ;; Deleting a file in the directory doesn't invalidate the watch.
 (delete-file "/tmp/foo/bla")
-     @result{} Event (35025468 deleted "/tmp/foo/bla")
+     @result{} Event (11359632 deleted "/tmp/foo/bla")
 @end group
 
 @group
 (write-region "bla" nil "/tmp/foo/bla")
-     @result{} Event (35025468 created "/tmp/foo/.#bla")
-        Event (35025468 created "/tmp/foo/bla")
-        Event (35025468 changed "/tmp/foo/bla")
-        Event (35025468 changed "/tmp/foo/.#bla")
+     @result{} Event (11359632 created "/tmp/foo/.#bla")
+        Event (11359632 created "/tmp/foo/bla")
+        Event (11359632 changed "/tmp/foo/bla")
+        Event (11359632 deleted "/tmp/foo/.#bla")
 @end group
 
 @group
 ;; Deleting the directory invalidates the watch.
+;; Events arrive for different watch descriptors.
 (delete-directory "/tmp/foo" 'recursive)
-     @result{} Event (35025468 deleted "/tmp/foo/bla")
-        Event (35025468 deleted "/tmp/foo")
-        Event (35025468 stopped "/tmp/foo")
+     @result{} Event (35025468 deleted "/tmp/foo")
+        Event (11359632 deleted "/tmp/foo/bla")
+        Event (11359632 deleted "/tmp/foo")
+        Event (11359632 stopped "/tmp/foo")
 @end group
 
 @group