diff options
Diffstat (limited to 'src/system-settings/nm-inotify-helper.c')
| -rw-r--r-- | src/system-settings/nm-inotify-helper.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/src/system-settings/nm-inotify-helper.c b/src/system-settings/nm-inotify-helper.c new file mode 100644 index 00000000..0ee168e5 --- /dev/null +++ b/src/system-settings/nm-inotify-helper.c @@ -0,0 +1,212 @@ +/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */ +/* NetworkManager system settings service + * + * This program 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 2 of the License, or + * (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + * (C) Copyright 2008 Red Hat, Inc. + */ + +#include <unistd.h> +#include <string.h> +#include <sys/inotify.h> +#include <glib.h> + +#include "nm-marshal.h" +#include "nm-inotify-helper.h" +#include "nm-logging.h" + +G_DEFINE_TYPE (NMInotifyHelper, nm_inotify_helper, G_TYPE_OBJECT) + +#define NM_INOTIFY_HELPER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_INOTIFY_HELPER, NMInotifyHelperPrivate)) + +typedef struct { + int ifd; + + GHashTable *wd_refs; +} NMInotifyHelperPrivate; + +/* Signals */ +enum { + EVENT, + LAST_SIGNAL +}; + +static guint signals[LAST_SIGNAL] = { 0 }; + +int +nm_inotify_helper_add_watch (NMInotifyHelper *self, const char *path) +{ + NMInotifyHelperPrivate *priv = NM_INOTIFY_HELPER_GET_PRIVATE (self); + int wd; + guint32 refcount; + + g_return_val_if_fail (priv->ifd >= 0, -1); + + /* We only care about modifications since we're just trying to get change + * notifications on hardlinks. + */ + + wd = inotify_add_watch (priv->ifd, path, IN_CLOSE_WRITE); + if (wd < 0) + return -1; + + refcount = GPOINTER_TO_UINT (g_hash_table_lookup (priv->wd_refs, GINT_TO_POINTER (wd))); + refcount++; + g_hash_table_replace (priv->wd_refs, GINT_TO_POINTER (wd), GUINT_TO_POINTER (refcount)); + + return wd; +} + +void +nm_inotify_helper_remove_watch (NMInotifyHelper *self, int wd) +{ + NMInotifyHelperPrivate *priv = NM_INOTIFY_HELPER_GET_PRIVATE (self); + guint32 refcount; + + g_return_if_fail (priv->ifd >= 0); + + refcount = GPOINTER_TO_UINT (g_hash_table_lookup (priv->wd_refs, GINT_TO_POINTER (wd))); + if (!refcount) + return; + + refcount--; + if (!refcount) { + g_hash_table_remove (priv->wd_refs, GINT_TO_POINTER (wd)); + inotify_rm_watch (priv->ifd, wd); + } else + g_hash_table_replace (priv->wd_refs, GINT_TO_POINTER (wd), GUINT_TO_POINTER (refcount)); +} + +static gboolean +inotify_event_handler (GIOChannel *channel, GIOCondition cond, gpointer user_data) +{ + NMInotifyHelper *self = NM_INOTIFY_HELPER (user_data); + struct inotify_event evt; + + /* read the notifications from the watch descriptor */ + while (g_io_channel_read_chars (channel, (gchar *) &evt, sizeof (struct inotify_event), NULL, NULL) == G_IO_STATUS_NORMAL) { + gchar filename[PATH_MAX + 1]; + + filename[0] = '\0'; + if (evt.len > 0) { + g_io_channel_read_chars (channel, + filename, + evt.len > PATH_MAX ? PATH_MAX : evt.len, + NULL, NULL); + } + + if (!(evt.mask & IN_IGNORED)) + g_signal_emit (self, signals[EVENT], 0, &evt, &filename[0]); + } + + return TRUE; +} + +static gboolean +init_inotify (NMInotifyHelper *self) +{ + NMInotifyHelperPrivate *priv = NM_INOTIFY_HELPER_GET_PRIVATE (self); + GIOChannel *channel; + guint source_id; + + priv->ifd = inotify_init (); + if (priv->ifd == -1) { + nm_log_warn (LOGD_SYS_SET, "couldn't initialize inotify"); + return FALSE; + } + + /* Watch the inotify descriptor for file/directory change events */ + channel = g_io_channel_unix_new (priv->ifd); + if (!channel) { + nm_log_warn (LOGD_SYS_SET, "couldn't create new GIOChannel"); + close (priv->ifd); + priv->ifd = -1; + return FALSE; + } + + g_io_channel_set_flags (channel, G_IO_FLAG_NONBLOCK, NULL); + g_io_channel_set_encoding (channel, NULL, NULL); + + source_id = g_io_add_watch (channel, + G_IO_IN | G_IO_ERR, + (GIOFunc) inotify_event_handler, + (gpointer) self); + g_io_channel_unref (channel); + return TRUE; +} + +NMInotifyHelper * +nm_inotify_helper_get (void) +{ + static NMInotifyHelper *singleton = NULL; + + if (!singleton) { + singleton = (NMInotifyHelper *) g_object_new (NM_TYPE_INOTIFY_HELPER, NULL); + if (!singleton) + return NULL; + + if (!init_inotify (singleton)) { + g_object_unref (singleton); + return NULL; + } + } else + g_object_ref (singleton); + + g_assert (singleton); + return singleton; +} + +static void +nm_inotify_helper_init (NMInotifyHelper *self) +{ + NMInotifyHelperPrivate *priv = NM_INOTIFY_HELPER_GET_PRIVATE (self); + + priv->wd_refs = g_hash_table_new (g_direct_hash, g_direct_equal); +} + +static void +finalize (GObject *object) +{ + NMInotifyHelperPrivate *priv = NM_INOTIFY_HELPER_GET_PRIVATE (object); + + if (priv->ifd >= 0) + close (priv->ifd); + + g_hash_table_destroy (priv->wd_refs); + + G_OBJECT_CLASS (nm_inotify_helper_parent_class)->finalize (object); +} + +static void +nm_inotify_helper_class_init (NMInotifyHelperClass *klass) +{ + GObjectClass *object_class = G_OBJECT_CLASS (klass); + + g_type_class_add_private (klass, sizeof (NMInotifyHelperPrivate)); + + /* Virtual methods */ + object_class->finalize = finalize; + + /* Signals */ + signals[EVENT] = + g_signal_new ("event", + G_OBJECT_CLASS_TYPE (object_class), + G_SIGNAL_RUN_LAST, + G_STRUCT_OFFSET (NMInotifyHelperClass, event), + NULL, NULL, + _nm_marshal_VOID__POINTER_STRING, + G_TYPE_NONE, 2, G_TYPE_POINTER, G_TYPE_STRING); +} + |