all messages for Emacs-related lists mirrored at yhetil.org
 help / color / mirror / code / Atom feed
blob 5694405e364e9be5b83293e8be5313a81ea93d06 10272 bytes (raw)
name: src/gfilenotify.c 	 # note: path name is non-authoritative(*)

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
 
/* Filesystem notifications support with glib API.
   Copyright (C) 2013-2016 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_GFILENOTIFY
#include <stdio.h>
#include <gio/gio.h>
#include "lisp.h"
#include "coding.h"
#include "termhooks.h"
#include "keyboard.h"

\f
/* This is a list, elements are triples (DESCRIPTOR FILE FLAGS CALLBACK)  */
static Lisp_Object watch_list;

/* 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;
}

DEFUN ("gfile-add-watch", Fgfile_add_watch, Sgfile_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;

  /* 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;
    }
}

\f
void
globals_of_gfilenotify (void)
{
#if ! GLIB_CHECK_VERSION (2, 36, 0)
  g_type_init ();
#endif
  watch_list = Qnil;
}

void
syms_of_gfilenotify (void)
{
  defsubr (&Sgfile_add_watch);
  defsubr (&Sgfile_rm_watch);
  defsubr (&Sgfile_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 (Qchanged, "changed");	/* G_FILE_MONITOR_EVENT_CHANGED  */
  DEFSYM (Qchanges_done_hint, "changes-done-hint");
				/* G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT  */
  DEFSYM (Qdeleted, "deleted");	/* G_FILE_MONITOR_EVENT_DELETED  */
  DEFSYM (Qcreated, "created");	/* G_FILE_MONITOR_EVENT_CREATED  */
  DEFSYM (Qattribute_changed, "attribute-changed");
				/* G_FILE_MONITOR_EVENT_ATTRIBUTE_CHANGED  */
  DEFSYM (Qpre_unmount, "pre-unmount");	/* G_FILE_MONITOR_EVENT_PRE_UNMOUNT  */
  DEFSYM (Qunmounted, "unmounted");	/* G_FILE_MONITOR_EVENT_UNMOUNTED  */
  DEFSYM (Qmoved, "moved");	/* G_FILE_MONITOR_EVENT_MOVED  */

  staticpro (&watch_list);

  Fprovide (intern_c_string ("gfilenotify"), Qnil);

}

#endif /* HAVE_GFILENOTIFY  */

debug log:

solving 5694405 ...
found 5694405 in https://yhetil.org/emacs/87h95olvg0.fsf@gmail.com/
found 30d0753 in https://git.savannah.gnu.org/cgit/emacs.git
preparing index
index prepared:
100644 30d0753f7e76f66c0a9ff0373398adaffd311d5e	src/gfilenotify.c

applying [1/1] https://yhetil.org/emacs/87h95olvg0.fsf@gmail.com/
diff --git a/src/gfilenotify.c b/src/gfilenotify.c
index 30d0753..5694405 100644

Checking patch src/gfilenotify.c...
Applied patch src/gfilenotify.c cleanly.

index at:
100644 5694405e364e9be5b83293e8be5313a81ea93d06	src/gfilenotify.c

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this external index

	https://git.savannah.gnu.org/cgit/emacs.git
	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.