Add kqueue support

* 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.

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

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

* src/kqueue.c: New file.

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

1 files changed, 339 insertions, 0 deletions

diff --git a/src/kqueue.c b/src/kqueue.c
new file mode 100644
index 00000000000..69bf5f61080
--- /dev/null
+++ b/src/kqueue.c
@@ -0,0 +1,339 @@
+/* Filesystem notifications support with glib API.
+   Copyright (C) 2013-2015 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs 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 3 of the License, or
+(at your option) any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#ifdef HAVE_KQUEUE
+#include <stdio.h>
+#include <sys/event.h>
+#include "lisp.h"
+#include "coding.h"
+#include "termhooks.h"
+#include "keyboard.h"
+
+
+/* File handle for kqueue.  */
+static int kqueuefd = -1;
+
+/* This is a list, elements are triples (DESCRIPTOR FILE FLAGS CALLBACK)  */
+static Lisp_Object watch_list;
+
+#if 0
+/* This is the callback function for arriving signals from
+   g_file_monitor.  It shall create a Lisp event, and put it into
+   Emacs input queue.  */
+static gboolean
+dir_monitor_callback (GFileMonitor *monitor,
+		      GFile *file,
+		      GFile *other_file,
+		      GFileMonitorEvent event_type,
+		      gpointer user_data)
+{
+  Lisp_Object symbol, monitor_object, watch_object, flags;
+  char *name = g_file_get_parse_name (file);
+  char *oname = other_file ? g_file_get_parse_name (other_file) : NULL;
+
+  /* Determine event symbol.  */
+  switch (event_type)
+    {
+    case G_FILE_MONITOR_EVENT_CHANGED:
+      symbol = Qchanged;
+      break;
+    case G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT:
+      symbol = Qchanges_done_hint;
+      break;
+    case G_FILE_MONITOR_EVENT_DELETED:
+      symbol = Qdeleted;
+      break;
+    case G_FILE_MONITOR_EVENT_CREATED:
+      symbol = Qcreated;
+      break;
+    case G_FILE_MONITOR_EVENT_ATTRIBUTE_CHANGED:
+      symbol = Qattribute_changed;
+      break;
+    case G_FILE_MONITOR_EVENT_PRE_UNMOUNT:
+      symbol = Qpre_unmount;
+      break;
+    case G_FILE_MONITOR_EVENT_UNMOUNTED:
+      symbol = Qunmounted;
+      break;
+    case G_FILE_MONITOR_EVENT_MOVED:
+      symbol = Qmoved;
+      break;
+    default:
+      goto cleanup;
+    }
+
+  /* Determine callback function.  */
+  monitor_object = make_pointer_integer (monitor);
+  eassert (INTEGERP (monitor_object));
+  watch_object = assq_no_quit (monitor_object, watch_list);
+
+  if (CONSP (watch_object))
+    {
+      struct input_event event;
+      Lisp_Object otail = oname ? list1 (build_string (oname)) : Qnil;
+
+      /* Check, whether event_type is expected.  */
+      flags = XCAR (XCDR (XCDR (watch_object)));
+      if ((!NILP (Fmember (Qchange, flags)) &&
+	   !NILP (Fmember (symbol, list5 (Qchanged, Qchanges_done_hint,
+					  Qdeleted, Qcreated, Qmoved)))) ||
+	  (!NILP (Fmember (Qattribute_change, flags)) &&
+	   ((EQ (symbol, Qattribute_changed)))))
+	{
+	  /* Construct an event.  */
+	  EVENT_INIT (event);
+	  event.kind = FILE_NOTIFY_EVENT;
+	  event.frame_or_window = Qnil;
+	  event.arg = list2 (Fcons (monitor_object,
+				    Fcons (symbol,
+					   Fcons (build_string (name),
+						  otail))),
+			     XCAR (XCDR (XCDR (XCDR (watch_object)))));
+
+	  /* Store it into the input event queue.  */
+	  kbd_buffer_store_event (&event);
+	  // XD_DEBUG_MESSAGE ("%s", XD_OBJECT_TO_STRING (event.arg));
+	}
+
+      /* Cancel monitor if file or directory is deleted.  */
+      if (!NILP (Fmember (symbol, list2 (Qdeleted, Qmoved))) &&
+	  (strcmp (name, SSDATA (XCAR (XCDR (watch_object)))) == 0) &&
+	  !g_file_monitor_is_cancelled (monitor))
+	g_file_monitor_cancel (monitor);
+    }
+
+  /* Cleanup.  */
+ cleanup:
+  g_free (name);
+  g_free (oname);
+
+  return TRUE;
+}
+#endif /* 0  */
+
+DEFUN ("kqueue-add-watch", Fkqueue_add_watch, Skqueue_add_watch, 3, 3, 0,
+       doc: /* Add a watch for filesystem events pertaining to FILE.
+
+This arranges for filesystem events pertaining to FILE to be reported
+to Emacs.  Use `gfile-rm-watch' to cancel the watch.
+
+Value is a descriptor for the added watch.  If the file cannot be
+watched for some reason, this function signals a `file-notify-error' error.
+
+FLAGS is a list of conditions to set what will be watched for.  It can
+include the following symbols:
+
+  `change'           -- watch for file changes
+  `attribute-change' -- watch for file attributes changes, like
+                        permissions or modification time
+  `watch-mounts'     -- watch for mount events
+  `send-moved'       -- pair `deleted' and `created' events caused by
+                        file renames and send a single `renamed' event
+                        instead
+
+When any event happens, Emacs will call the CALLBACK function passing
+it a single argument EVENT, which is of the form
+
+  (DESCRIPTOR ACTION FILE [FILE1])
+
+DESCRIPTOR is the same object as the one returned by this function.
+ACTION is the description of the event.  It could be any one of the
+following:
+
+  `changed'           -- FILE has changed
+  `changes-done-hint' -- a hint that this was probably the last change
+                         in a set of changes
+  `deleted'           -- FILE was deleted
+  `created'           -- FILE was created
+  `attribute-changed' -- a FILE attribute was changed
+  `pre-unmount'       -- the FILE location will soon be unmounted
+  `unmounted'         -- the FILE location was unmounted
+  `moved'             -- FILE was moved to FILE1
+
+FILE is the name of the file whose event is being reported.  FILE1
+will be reported only in case of the `moved' event.  */)
+  (Lisp_Object file, Lisp_Object flags, Lisp_Object callback)
+{
+  Lisp_Object watch_object;
+  GFile *gfile;
+  GFileMonitor *monitor;
+  GFileMonitorFlags gflags = G_FILE_MONITOR_NONE;
+  GError *gerror = NULL;
+
+  /* Check parameters.  */
+  CHECK_STRING (file);
+  file = Fdirectory_file_name (Fexpand_file_name (file, Qnil));
+  if (NILP (Ffile_exists_p (file)))
+    report_file_error ("File does not exist", file);
+
+  CHECK_LIST (flags);
+
+  if (!FUNCTIONP (callback))
+    wrong_type_argument (Qinvalid_function, callback);
+
+  /* Create GFile name.  */
+  //  gfile = g_file_new_for_path (SSDATA (ENCODE_FILE (file)));
+
+  /* Assemble flags.  */
+  //  if (!NILP (Fmember (Qwatch_mounts, flags)))
+  //    gflags |= G_FILE_MONITOR_WATCH_MOUNTS;
+  //  if (!NILP (Fmember (Qsend_moved, flags)))
+  //    gflags |= G_FILE_MONITOR_SEND_MOVED;
+
+  if (kqueuefd < 0)
+    {
+      kqueuefd = kqueue ();
+      if (kqueuefd < 0)
+	report_file_notify_error ("File watching is not available", Qnil);
+      watch_list = Qnil;
+      //      add_read_fd (inotifyfd, &inotify_callback, NULL);
+    }
+
+
+}
+#if 0
+
+  mask = aspect_to_inotifymask (aspect);
+  encoded_file_name = ENCODE_FILE (file_name);
+  watchdesc = inotify_add_watch (inotifyfd, SSDATA (encoded_file_name), mask);
+  if (watchdesc == -1)
+    report_file_notify_error ("Could not add watch for file", file_name);
+
+  /* Enable watch.  */
+  monitor = g_file_monitor (gfile, gflags, NULL, &gerror);
+  g_object_unref (gfile);
+  if (gerror)
+    {
+      char msg[1024];
+      strcpy (msg, gerror->message);
+      g_error_free (gerror);
+      xsignal1 (Qfile_notify_error, build_string (msg));
+    }
+  if (! monitor)
+    xsignal2 (Qfile_notify_error, build_string ("Cannot watch file"), file);
+
+  Lisp_Object watch_descriptor = make_pointer_integer (monitor);
+
+  /* Check the dicey assumption that make_pointer_integer is safe.  */
+  if (! INTEGERP (watch_descriptor))
+    {
+      g_object_unref (monitor);
+      xsignal2 (Qfile_notify_error, build_string ("Unsupported file watcher"),
+		file);
+    }
+
+  /* The default rate limit is 800 msec.  We adapt this.  */
+  g_file_monitor_set_rate_limit (monitor, 100);
+
+  /* Subscribe to the "changed" signal.  */
+  g_signal_connect (monitor, "changed",
+		    (GCallback) dir_monitor_callback, NULL);
+
+  /* Store watch object in watch list.  */
+  watch_object = list4 (watch_descriptor, file, flags, callback);
+  watch_list = Fcons (watch_object, watch_list);
+
+  return watch_descriptor;
+}
+
+DEFUN ("gfile-rm-watch", Fgfile_rm_watch, Sgfile_rm_watch, 1, 1, 0,
+       doc: /* Remove an existing WATCH-DESCRIPTOR.
+
+WATCH-DESCRIPTOR should be an object returned by `gfile-add-watch'.  */)
+     (Lisp_Object watch_descriptor)
+{
+  Lisp_Object watch_object = assq_no_quit (watch_descriptor, watch_list);
+
+  if (! CONSP (watch_object))
+    xsignal2 (Qfile_notify_error, build_string ("Not a watch descriptor"),
+	      watch_descriptor);
+
+  eassert (INTEGERP (watch_descriptor));
+  GFileMonitor *monitor = XINTPTR (watch_descriptor);
+  if (!g_file_monitor_is_cancelled (monitor) &&
+      !g_file_monitor_cancel (monitor))
+      xsignal2 (Qfile_notify_error, build_string ("Could not rm watch"),
+		watch_descriptor);
+
+  /* Remove watch descriptor from watch list.  */
+  watch_list = Fdelq (watch_object, watch_list);
+
+  /* Cleanup.  */
+  g_object_unref (monitor);
+
+  return Qt;
+}
+
+DEFUN ("gfile-valid-p", Fgfile_valid_p, Sgfile_valid_p, 1, 1, 0,
+       doc: /* "Check a watch specified by its WATCH-DESCRIPTOR.
+
+WATCH-DESCRIPTOR should be an object returned by `gfile-add-watch'.
+
+A watch can become invalid if the file or directory it watches is
+deleted, or if the watcher thread exits abnormally for any other
+reason.  Removing the watch by calling `gfile-rm-watch' also makes it
+invalid.  */)
+     (Lisp_Object watch_descriptor)
+{
+  Lisp_Object watch_object = Fassoc (watch_descriptor, watch_list);
+  if (NILP (watch_object))
+    return Qnil;
+  else
+    {
+      GFileMonitor *monitor = XINTPTR (watch_descriptor);
+      return g_file_monitor_is_cancelled (monitor) ? Qnil : Qt;
+    }
+}
+#endif /* 0  */
+
+
+void
+globals_of_kqueue (void)
+{
+  watch_list = Qnil;
+}
+
+void
+syms_of_kqueue (void)
+{
+  defsubr (&Skqueue_add_watch);
+  //  defsubr (&Skqueue_rm_watch);
+  //  defsubr (&Skqueue_valid_p);
+
+  /* Filter objects.  */
+  DEFSYM (Qchange, "change");
+  DEFSYM (Qattribute_change, "attribute-change");
+  DEFSYM (Qwatch_mounts, "watch-mounts"); /* G_FILE_MONITOR_WATCH_MOUNTS  */
+  DEFSYM (Qsend_moved, "send-moved");	/* G_FILE_MONITOR_SEND_MOVED  */
+
+  /* Event types.  */
+  DEFSYM (Qdelete, "delete");	/* NOTE_DELETE  */
+  DEFSYM (Qwrite, "write");	/* NOTE_WRITE  */
+  DEFSYM (Qextend, "extend");	/* NOTE_EXTEND  */
+  DEFSYM (Qattrib, "attrib");	/* NOTE_ATTRIB  */
+  DEFSYM (Qlink, "link");	/* NOTE_LINK  */
+  DEFSYM (Qrename, "rename");	/* NOTE_RENAME  */
+
+  staticpro (&watch_list);
+
+  Fprovide (intern_c_string ("kqueue"), Qnil);
+}
+
+#endif /* HAVE_KQUEUE  */