glib/gio/kqueue/kqueue-helper.c
Martin Pieuchot aa39a0557c kqueue: Multiple fixes and simplifications
- Stop using a custom thread for listening to kqueue(2) events.  Instead
   call kevent(2) in non blocking mode in a monitor callback.  Under the
   hood poll(2) is used to figure out if new events are available.

 - Do not use a socketpair with a custom protocol requiring 2 supplementary
   context switches per event to commicate between multiple threads.  Calling
   kevent(2), in non blocking mode, to add/remove events is fine from any
   context.

 - Add kqueue(2) events without the EV_ONESHOT flag.  This removes a race
   where some notifications were lost because events had to be re-added for
   every new notification.

 - Get rid of the global hash table and its associated lock and races.  Use
   the 'cookie' argument of kevent(2) to pass the associated descriptor when
   registering an event.

 - Fix _kh_file_appeared_cb() by properly passing a monitor instead of a
   source to g_file_monitor_emit_event().

 - Properly refcount sources.

 - Remove a lot of abstraction making it harder to fix the remaining issues.

https://bugzilla.gnome.org/show_bug.cgi?id=739424
2018-03-13 12:23:10 +00:00

182 lines
5.4 KiB
C

/*******************************************************************************
Copyright (c) 2011, 2012 Dmitry Matveev <me@dmitrymatveev.co.uk>
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*******************************************************************************/
#include "config.h"
#include <sys/types.h>
#include <sys/event.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <gio/glocalfile.h>
#include <gio/glocalfilemonitor.h>
#include <gio/gfile.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include "kqueue-helper.h"
typedef struct {
kqueue_sub *sub;
GFileMonitorSource *source;
} handle_ctx;
/**
* handle_created:
* @udata: a pointer to user data (#handle_context).
* @path: file name of a new file.
* @inode: inode number of a new file.
*
* A callback function for the directory diff calculation routine,
* produces G_FILE_MONITOR_EVENT_CREATED event for a created file.
**/
static void
handle_created (void *udata, const char *path, ino_t inode)
{
handle_ctx *ctx = NULL;
(void) inode;
ctx = (handle_ctx *) udata;
g_assert (udata != NULL);
g_assert (ctx->sub != NULL);
g_assert (ctx->source != NULL);
g_file_monitor_source_handle_event (ctx->source, G_FILE_MONITOR_EVENT_CREATED, path,
NULL, NULL, g_get_monotonic_time ());
}
/**
* handle_deleted:
* @udata: a pointer to user data (#handle_context).
* @path: file name of the removed file.
* @inode: inode number of the removed file.
*
* A callback function for the directory diff calculation routine,
* produces G_FILE_MONITOR_EVENT_DELETED event for a deleted file.
**/
static void
handle_deleted (void *udata, const char *path, ino_t inode)
{
handle_ctx *ctx = NULL;
(void) inode;
ctx = (handle_ctx *) udata;
g_assert (udata != NULL);
g_assert (ctx->sub != NULL);
g_assert (ctx->source != NULL);
g_file_monitor_source_handle_event (ctx->source, G_FILE_MONITOR_EVENT_DELETED, path,
NULL, NULL, g_get_monotonic_time ());
}
/**
* handle_moved:
* @udata: a pointer to user data (#handle_context).
* @from_path: file name of the source file.
* @from_inode: inode number of the source file.
* @to_path: file name of the replaced file.
* @to_inode: inode number of the replaced file.
*
* A callback function for the directory diff calculation routine,
* produces G_FILE_MONITOR_EVENT_RENAMED event on a move.
**/
static void
handle_moved (void *udata,
const char *from_path,
ino_t from_inode,
const char *to_path,
ino_t to_inode)
{
handle_ctx *ctx = NULL;
(void) from_inode;
(void) to_inode;
ctx = (handle_ctx *) udata;
g_assert (udata != NULL);
g_assert (ctx->sub != NULL);
g_assert (ctx->source != NULL);
g_file_monitor_source_handle_event (ctx->source, G_FILE_MONITOR_EVENT_RENAMED,
from_path, to_path, NULL, g_get_monotonic_time ());
}
/**
* handle_overwritten:
* @data: a pointer to user data (#handle_context).
* @path: file name of the overwritten file.
* @node: inode number of the overwritten file.
*
* A callback function for the directory diff calculation routine,
* produces G_FILE_MONITOR_EVENT_DELETED/CREATED event pair when
* an overwrite occurs in the directory (see dep-list for details).
**/
static void
handle_overwritten (void *udata, const char *path, ino_t inode)
{
handle_ctx *ctx = NULL;
(void) inode;
ctx = (handle_ctx *) udata;
g_assert (udata != NULL);
g_assert (ctx->sub != NULL);
g_assert (ctx->source != NULL);
g_file_monitor_source_handle_event (ctx->source, G_FILE_MONITOR_EVENT_DELETED,
path, NULL, NULL, g_get_monotonic_time ());
g_file_monitor_source_handle_event (ctx->source, G_FILE_MONITOR_EVENT_CREATED,
path, NULL, NULL, g_get_monotonic_time ());
}
static const traverse_cbs cbs = {
handle_created,
handle_deleted,
handle_moved,
handle_overwritten,
handle_moved,
NULL, /* many added */
NULL, /* many removed */
NULL, /* names updated */
};
void
_kh_dir_diff (kqueue_sub *sub)
{
dep_list *was;
handle_ctx ctx;
memset (&ctx, 0, sizeof (handle_ctx));
ctx.sub = sub;
ctx.source = sub->source;
was = sub->deps;
sub->deps = dl_listing (sub->filename);
dl_calculate (was, sub->deps, &cbs, &ctx);
dl_free (was);
}