#include "frame.h" /* needed by termhooks.h */
#include "termhooks.h" /* for FILE_NOTIFY_EVENT */
+#define DIRWATCH_SIGNATURE 0x01233210
+
struct notification {
BYTE *buf; /* buffer for ReadDirectoryChangesW */
OVERLAPPED *io_info; /* the OVERLAPPED structure for async I/O */
HANDLE dir; /* handle to the watched directory */
HANDLE thr; /* handle to the thread that watches */
int terminate; /* if non-zero, request for the thread to terminate */
+ unsigned signature;
};
-/* FIXME: this needs to be changed to support more that one request at
- a time. */
-static struct notification dirwatch;
-
/* Used for communicating notifications to the main thread. */
int notification_buffer_in_use;
BYTE file_notifications[16384];
DWORD notifications_size;
-HANDLE notifications_desc;
+void *notifications_desc;
static Lisp_Object Qfile_name, Qdirectory_name, Qattributes, Qsize;
static Lisp_Object Qlast_write_time, Qlast_access_time, Qcreation_time;
/* Signal to the main thread that we have file notifications for it to
process. */
static void
-send_notifications (BYTE *info, DWORD info_size, HANDLE hdir, int *terminate)
+send_notifications (BYTE *info, DWORD info_size, void *desc, int *terminate)
{
int done = 0;
FRAME_PTR f = SELECTED_FRAME ();
-
/* A single buffer is used to communicate all notifications to the
main thread. Since both the main thread and several watcher
threads could be active at the same time, we use a critical area
if (info_size)
memcpy (file_notifications, info, info_size);
notifications_size = info_size;
- notifications_desc = hdir;
+ notifications_desc = desc;
/* If PostMessage fails, the message queue is full. If that
happens, the last thing they will worry about is file
notifications. So we effectively discard the
CancelIo on the directory we watch, and watch_end did so.
The directory handle is already closed. We should clean up
and exit, signalling to the thread worker routine not to
- issue another call to ReadDirectoryChangesW. */
+ issue another call to ReadDirectoryChangesW. Note that we
+ don't free the dirwatch object itself; this is done by the
+ main thread in remove_watch. */
xfree (dirwatch->buf);
dirwatch->buf = NULL;
xfree (dirwatch->io_info);
else
{
/* Tell the main thread we have notifications for it. */
- send_notifications (dirwatch->buf, bytes_ret, dirwatch->dir,
+ send_notifications (dirwatch->buf, bytes_ret, dirwatch,
&dirwatch->terminate);
}
}
if (!status)
{
DebPrint (("watch_worker, abnormal exit: %lu\n", GetLastError ()));
+ /* We cannot remove the dirwatch object from watch_list,
+ because we are in a separate thread. So we free and
+ zero out all the pointers in the object, but do not
+ free the object itself. We also don't touch the
+ signature. This way, remove_watch can still identify
+ the object, remove it, and free its memory. */
xfree (dirwatch->buf);
dirwatch->buf = NULL;
xfree (dirwatch->io_info);
/* Launch a thread to watch changes to FILE in a directory open on
handle HDIR. */
-static int
+static struct notification *
start_watching (const char *file, HANDLE hdir, BOOL subdirs, DWORD flags)
{
- dirwatch.buf = xmalloc (16384);
- dirwatch.io_info = xzalloc (sizeof(OVERLAPPED));
+ struct notification *dirwatch = xzalloc (sizeof (struct notification));
+ HANDLE thr;
+
+ dirwatch->signature = DIRWATCH_SIGNATURE;
+ dirwatch->buf = xmalloc (16384);
+ dirwatch->io_info = xzalloc (sizeof(OVERLAPPED));
/* Stash a pointer to dirwatch structure for use by the completion
routine. According to MSDN documentation of ReadDirectoryChangesW:
"The hEvent member of the OVERLAPPED structure is not used by the
system, so you can use it yourself." */
- dirwatch.io_info->hEvent = &dirwatch;
- dirwatch.subtree = subdirs;
- dirwatch.filter = flags;
- dirwatch.watchee = xstrdup (file);
- dirwatch.terminate = 0;
- dirwatch.dir = hdir;
+ dirwatch->io_info->hEvent = dirwatch;
+ dirwatch->subtree = subdirs;
+ dirwatch->filter = flags;
+ dirwatch->watchee = xstrdup (file);
+ dirwatch->terminate = 0;
+ dirwatch->dir = hdir;
/* See w32proc.c where it calls CreateThread for the story behind
the 2nd and 5th argument in the call to CreateThread. */
- dirwatch.thr = CreateThread (NULL, 64 * 1024, watch_worker,
- (void *)&dirwatch, 0x00010000, NULL);
+ dirwatch->thr = CreateThread (NULL, 64 * 1024, watch_worker, (void *)dirwatch,
+ 0x00010000, NULL);
- if (!dirwatch.thr)
+ if (!dirwatch->thr)
{
- dirwatch.terminate = 1;
- xfree (dirwatch.buf);
- dirwatch.buf = NULL;
- xfree (dirwatch.io_info);
- dirwatch.io_info = NULL;
- xfree (dirwatch.watchee);
- dirwatch.watchee = NULL;
- dirwatch.dir = NULL;
- return -1;
+ xfree (dirwatch->buf);
+ xfree (dirwatch->io_info);
+ xfree (dirwatch->watchee);
+ xfree (dirwatch);
+ dirwatch = NULL;
}
- return 0;
+ return dirwatch;
}
/* Called from the main thread to start watching FILE in PARENT_DIR,
subject to FLAGS. If SUBDIRS is TRUE, watch the subdirectories of
- PARENT_DIR as well. Value is the handle on which the directory is
- open. */
-static HANDLE *
+ PARENT_DIR as well. Value is a pointer to 'struct notification'
+ used by the thread that watches the changes. */
+static struct notification *
add_watch (const char *parent_dir, const char *file, BOOL subdirs, DWORD flags)
{
HANDLE hdir;
+ struct notification *dirwatch = NULL;
if (!file || !*file)
return NULL;
if (hdir == INVALID_HANDLE_VALUE)
return NULL;
- if (start_watching (file, hdir, subdirs, flags) == 0)
- return hdir;
+ if ((dirwatch = start_watching (file, hdir, subdirs, flags)) == NULL)
+ CloseHandle (hdir);
- CloseHandle (hdir);
- return NULL;
+ return dirwatch;
}
-/* Stop watching a directory specified by its handle HDIR. */
+/* Stop watching a directory specified by a pointer to its dirwatch object. */
static int
-remove_watch (HANDLE hdir)
+remove_watch (struct notification *dirwatch)
{
- if (hdir == dirwatch.dir)
+ if (dirwatch && dirwatch->signature == DIRWATCH_SIGNATURE)
{
int i;
BOOL status;
CancelIo on it. (CancelIoEx is available only since Vista.)
So we need to queue an APC for the worker thread telling it
to terminate. */
- if (!QueueUserAPC (watch_end, dirwatch.thr, (ULONG_PTR)dirwatch.dir))
+ if (!QueueUserAPC (watch_end, dirwatch->thr, (ULONG_PTR)dirwatch->dir))
DebPrint (("QueueUserAPC failed (%lu)!\n", GetLastError ()));
/* We also set the terminate flag, for when the thread is
waiting on the critical section that never gets acquired.
FIXME: is there a cleaner method? Using SleepEx there is a
no-no, as that will lead to recursive APC invocations and
stack overflow. */
- dirwatch.terminate = 1;
+ dirwatch->terminate = 1;
/* Wait for the thread to exit. FIXME: is there a better method
that is not overly complex? */
for (i = 0; i < 50; i++)
{
- if (!((status = GetExitCodeThread (dirwatch.thr, &exit_code))
+ if (!((status = GetExitCodeThread (dirwatch->thr, &exit_code))
&& exit_code == STILL_ACTIVE))
break;
Sleep (10);
|| exit_code == STILL_ACTIVE)
{
if (!(status == FALSE && err == ERROR_INVALID_HANDLE))
- TerminateThread (dirwatch.thr, 0);
+ {
+ TerminateThread (dirwatch->thr, 0);
+ if (dirwatch->dir)
+ CloseHandle (dirwatch->dir);
+ }
}
/* Clean up. */
- if (dirwatch.thr)
+ if (dirwatch->thr)
{
- CloseHandle (dirwatch.thr);
- dirwatch.thr = NULL;
+ CloseHandle (dirwatch->thr);
+ dirwatch->thr = NULL;
}
- return 0;
- }
- else if (!dirwatch.dir)
- {
- DebPrint (("Directory handle already closed!\n"));
+ xfree (dirwatch->buf);
+ xfree (dirwatch->io_info);
+ xfree (dirwatch->watchee);
+ xfree (dirwatch);
+
return 0;
}
else
{
- DebPrint (("Unknown directory handle!\n"));
+ DebPrint (("Unknown dirwatch object!\n"));
return -1;
}
}
Lisp_Object encoded_file, watch_object, watch_descriptor;
char parent_dir[MAX_PATH], *basename;
size_t fn_len;
- HANDLE hdir;
DWORD flags;
BOOL subdirs = FALSE;
+ struct notification *dirwatch = NULL;
Lisp_Object lisp_errstr;
char *errstr;
Qnil);
}
- if (dirwatch.dir)
- error ("File watch already active");
-
- /* We needa full absolute file name of FILE, and we need to remove
+ /* We need a full absolute file name of FILE, and we need to remove
any trailing slashes from it, so that GetFullPathName below gets
the basename part correctly. */
file = Fdirectory_file_name (Fexpand_file_name (file, Qnil));
flags = filter_list_to_flags (filter);
- hdir = add_watch (parent_dir, basename, subdirs, flags);
- if (!hdir)
+ dirwatch = add_watch (parent_dir, basename, subdirs, flags);
+ if (!dirwatch)
{
DWORD err = GetLastError ();
report_file_error ("Cannot watch file", Fcons (file, Qnil));
}
/* Store watch object in watch list. */
- watch_descriptor = make_number (hdir);
+ watch_descriptor = make_number (dirwatch);
watch_object = Fcons (watch_descriptor, callback);
watch_list = Fcons (watch_object, watch_list);
(Lisp_Object watch_descriptor)
{
Lisp_Object watch_object;
- HANDLE hdir = (HANDLE)XINT (watch_descriptor);
+ struct notification *dirwatch =
+ (struct notification *)XINT (watch_descriptor);
- if (remove_watch (hdir) == -1)
- report_file_error ("Could not remove watch", Fcons (watch_descriptor,
- Qnil));
-
- /* Remove watch descriptor from watch list. */
+ /* Remove the watch object from watch list. Do this before freeing
+ the object, do that even if we fail to free it, watch_list is
+ kept free of junk. */
watch_object = Fassoc (watch_descriptor, watch_list);
if (!NILP (watch_object))
watch_list = Fdelete (watch_object, watch_list);
+ if (remove_watch (dirwatch) == -1)
+ report_file_error ("Invalid watch descriptor", Fcons (watch_descriptor,
+ Qnil));
+
return Qnil;
}
Lisp_Object
-get_watch_object (Lisp_Object desc)
+w32_get_watch_object (Lisp_Object desc)
+{
+ return NILP (watch_list) ? Qnil : assoc_no_quit (desc, watch_list);
+}
+
+void
+globals_of_w32notify (void)
{
- return Fassoc (desc, watch_list);
+ watch_list = Qnil;
}
void
HCoop / bpt / emacs.git / commitdiff