/* GIO - GLib Input, Output and Streaming Library * * Copyright (C) 2006-2007 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * Public License along with this library; if not, see . * * Author: Alexander Larsson */ #include "config.h" #include "gioenumtypes.h" #include "glocalfilemonitor.h" #include "giomodule-priv.h" #include "gioerror.h" #include "glibintl.h" #include "glocalfile.h" #include "glib-private.h" #include #define DEFAULT_RATE_LIMIT 800 * G_TIME_SPAN_MILLISECOND #define VIRTUAL_CHANGES_DONE_DELAY 2 * G_TIME_SPAN_SECOND /* GFileMonitorSource is a GSource responsible for emitting the changed * signals in the owner-context of the GFileMonitor. * * It contains functionality for cross-thread queuing of events. It * also handles merging of CHANGED events and emission of CHANGES_DONE * events. * * We use the "priv" pointer in the external struct to store it. */ struct _GFileMonitorSource { GSource source; GMutex lock; gpointer instance; GFileMonitorFlags flags; gchar *dirname; gchar *basename; gchar *filename; GSequence *pending_changes; /* sorted by ready time */ GHashTable *pending_changes_table; GQueue event_queue; gint64 rate_limit; }; /* PendingChange is a struct to keep track of a file that needs to have * (at least) a CHANGES_DONE_HINT event sent for it in the near future. * * If 'dirty' is TRUE then a CHANGED event also needs to be sent. * * last_emission is the last time a CHANGED event was emitted. It is * used to calculate the time to send the next event. */ typedef struct { gchar *child; guint64 last_emission : 63; guint64 dirty : 1; } PendingChange; /* QueuedEvent is a signal that will be sent immediately, as soon as the * source gets a chance to dispatch. The existence of any queued event * implies that the source is ready now. */ typedef struct { GFileMonitorEvent event_type; GFile *child; GFile *other; } QueuedEvent; static gint64 pending_change_get_ready_time (const PendingChange *change, GFileMonitorSource *fms) { if (change->dirty) return change->last_emission + fms->rate_limit; else return change->last_emission + VIRTUAL_CHANGES_DONE_DELAY; } static int pending_change_compare_ready_time (gconstpointer a_p, gconstpointer b_p, gpointer user_data) { GFileMonitorSource *fms = user_data; const PendingChange *a = a_p; const PendingChange *b = b_p; gint64 ready_time_a; gint64 ready_time_b; ready_time_a = pending_change_get_ready_time (a, fms); ready_time_b = pending_change_get_ready_time (b, fms); if (ready_time_a < ready_time_b) return -1; else return ready_time_a > ready_time_b; } static void pending_change_free (gpointer data) { PendingChange *change = data; g_free (change->child); g_slice_free (PendingChange, change); } static void queued_event_free (QueuedEvent *event) { g_object_unref (event->child); if (event->other) g_object_unref (event->other); g_slice_free (QueuedEvent, event); } static gint64 g_file_monitor_source_get_ready_time (GFileMonitorSource *fms) { GSequenceIter *iter; if (fms->event_queue.length) return 0; iter = g_sequence_get_begin_iter (fms->pending_changes); if (g_sequence_iter_is_end (iter)) return -1; return pending_change_get_ready_time (g_sequence_get (iter), fms); } static void g_file_monitor_source_update_ready_time (GFileMonitorSource *fms) { g_source_set_ready_time ((GSource *) fms, g_file_monitor_source_get_ready_time (fms)); } static GSequenceIter * g_file_monitor_source_find_pending_change (GFileMonitorSource *fms, const gchar *child) { return g_hash_table_lookup (fms->pending_changes_table, child); } static void g_file_monitor_source_add_pending_change (GFileMonitorSource *fms, const gchar *child, gint64 now) { PendingChange *change; GSequenceIter *iter; change = g_slice_new (PendingChange); change->child = g_strdup (child); change->last_emission = now; change->dirty = FALSE; iter = g_sequence_insert_sorted (fms->pending_changes, change, pending_change_compare_ready_time, fms); g_hash_table_insert (fms->pending_changes_table, change->child, iter); } static gboolean g_file_monitor_source_set_pending_change_dirty (GFileMonitorSource *fms, GSequenceIter *iter) { PendingChange *change; change = g_sequence_get (iter); /* if it was already dirty then this change is 'uninteresting' */ if (change->dirty) return FALSE; change->dirty = TRUE; g_sequence_sort_changed (iter, pending_change_compare_ready_time, fms); return TRUE; } static gboolean g_file_monitor_source_get_pending_change_dirty (GFileMonitorSource *fms, GSequenceIter *iter) { PendingChange *change; change = g_sequence_get (iter); return change->dirty; } static void g_file_monitor_source_remove_pending_change (GFileMonitorSource *fms, GSequenceIter *iter, const gchar *child) { /* must remove the hash entry first -- its key is owned by the data * which will be freed when removing the sequence iter */ g_hash_table_remove (fms->pending_changes_table, child); g_sequence_remove (iter); } static void g_file_monitor_source_queue_event (GFileMonitorSource *fms, GFileMonitorEvent event_type, const gchar *child, GFile *other) { QueuedEvent *event; event = g_slice_new (QueuedEvent); event->event_type = event_type; if (child) event->child = g_local_file_new_from_dirname_and_basename (fms->dirname, child); else if (fms->dirname) event->child = _g_local_file_new (fms->dirname); else if (fms->filename) event->child = _g_local_file_new (fms->filename); event->other = other; if (other) g_object_ref (other); g_queue_push_tail (&fms->event_queue, event); } static gboolean g_file_monitor_source_file_changed (GFileMonitorSource *fms, const gchar *child, gint64 now) { GSequenceIter *pending; gboolean interesting; pending = g_file_monitor_source_find_pending_change (fms, child); /* If there is no pending change, emit one and create a record, * else: just mark the existing record as dirty. */ if (!pending) { g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGED, child, NULL); g_file_monitor_source_add_pending_change (fms, child, now); interesting = TRUE; } else interesting = g_file_monitor_source_set_pending_change_dirty (fms, pending); g_file_monitor_source_update_ready_time (fms); return interesting; } static void g_file_monitor_source_file_changes_done (GFileMonitorSource *fms, const gchar *child) { GSequenceIter *pending; pending = g_file_monitor_source_find_pending_change (fms, child); if (pending) { /* If it is dirty, make sure we push out the last CHANGED event */ if (g_file_monitor_source_get_pending_change_dirty (fms, pending)) g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGED, child, NULL); g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT, child, NULL); g_file_monitor_source_remove_pending_change (fms, pending, child); } } static void g_file_monitor_source_file_created (GFileMonitorSource *fms, const gchar *child, gint64 event_time) { /* Unlikely, but if we have pending changes for this filename, make * sure we flush those out first, before creating the new ones. */ g_file_monitor_source_file_changes_done (fms, child); /* Emit CREATE and add a pending changes record */ g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CREATED, child, NULL); g_file_monitor_source_add_pending_change (fms, child, event_time); } static void g_file_monitor_source_send_event (GFileMonitorSource *fms, GFileMonitorEvent event_type, const gchar *child, GFile *other) { /* always flush any pending changes before we queue a new event */ g_file_monitor_source_file_changes_done (fms, child); g_file_monitor_source_queue_event (fms, event_type, child, other); } static void g_file_monitor_source_send_synthetic_created (GFileMonitorSource *fms, const gchar *child) { g_file_monitor_source_file_changes_done (fms, child); g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CREATED, child, NULL); g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT, child, NULL); } static gboolean is_basename (const gchar *name) { if (name[0] == '.' && ((name[1] == '.' && name[2] == '\0') || name[1] == '\0')) return FALSE; return !strchr (name, '/'); } gboolean g_file_monitor_source_handle_event (GFileMonitorSource *fms, GFileMonitorEvent event_type, const gchar *child, const gchar *rename_to, GFile *other, gint64 event_time) { gboolean interesting = TRUE; g_assert (!child || is_basename (child)); g_assert (!rename_to || is_basename (rename_to)); if (fms->basename && (!child || !g_str_equal (child, fms->basename)) && (!rename_to || !g_str_equal (rename_to, fms->basename))) return TRUE; g_mutex_lock (&fms->lock); /* monitor is already gone -- don't bother */ if (!fms->instance) { g_mutex_unlock (&fms->lock); return TRUE; } switch (event_type) { case G_FILE_MONITOR_EVENT_CREATED: g_assert (!other && !rename_to); g_file_monitor_source_file_created (fms, child, event_time); break; case G_FILE_MONITOR_EVENT_CHANGED: g_assert (!other && !rename_to); interesting = g_file_monitor_source_file_changed (fms, child, event_time); break; case G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT: g_assert (!other && !rename_to); g_file_monitor_source_file_changes_done (fms, child); break; case G_FILE_MONITOR_EVENT_MOVED_IN: g_assert (!rename_to); if (fms->flags & G_FILE_MONITOR_WATCH_MOVES) g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_MOVED_IN, child, other); else g_file_monitor_source_send_synthetic_created (fms, child); break; case G_FILE_MONITOR_EVENT_MOVED_OUT: g_assert (!rename_to); if (fms->flags & G_FILE_MONITOR_WATCH_MOVES) g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_MOVED_OUT, child, other); else if (other && (fms->flags & G_FILE_MONITOR_SEND_MOVED)) g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_MOVED, child, other); else g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_DELETED, child, NULL); break; case G_FILE_MONITOR_EVENT_RENAMED: g_assert (!other && rename_to); if (fms->flags & G_FILE_MONITOR_WATCH_MOVES) { GFile *other; other = g_local_file_new_from_dirname_and_basename (fms->dirname, rename_to); g_file_monitor_source_file_changes_done (fms, rename_to); g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_RENAMED, child, other); g_object_unref (other); } else if (fms->flags & G_FILE_MONITOR_SEND_MOVED) { GFile *other; other = g_local_file_new_from_dirname_and_basename (fms->dirname, rename_to); g_file_monitor_source_file_changes_done (fms, rename_to); g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_MOVED, child, other); g_object_unref (other); } else { g_file_monitor_source_send_event (fms, G_FILE_MONITOR_EVENT_DELETED, child, NULL); g_file_monitor_source_send_synthetic_created (fms, rename_to); } break; case G_FILE_MONITOR_EVENT_DELETED: case G_FILE_MONITOR_EVENT_ATTRIBUTE_CHANGED: case G_FILE_MONITOR_EVENT_PRE_UNMOUNT: case G_FILE_MONITOR_EVENT_UNMOUNTED: g_assert (!other && !rename_to); g_file_monitor_source_send_event (fms, event_type, child, NULL); break; case G_FILE_MONITOR_EVENT_MOVED: /* was never available in this API */ default: g_assert_not_reached (); } g_file_monitor_source_update_ready_time (fms); g_mutex_unlock (&fms->lock); return interesting; } static gint64 g_file_monitor_source_get_rate_limit (GFileMonitorSource *fms) { gint64 rate_limit; g_mutex_lock (&fms->lock); rate_limit = fms->rate_limit; g_mutex_unlock (&fms->lock); return rate_limit; } static gboolean g_file_monitor_source_set_rate_limit (GFileMonitorSource *fms, gint64 rate_limit) { gboolean changed; g_mutex_lock (&fms->lock); if (rate_limit != fms->rate_limit) { fms->rate_limit = rate_limit; g_sequence_sort (fms->pending_changes, pending_change_compare_ready_time, fms); g_file_monitor_source_update_ready_time (fms); changed = TRUE; } else changed = FALSE; g_mutex_unlock (&fms->lock); return changed; } static gboolean g_file_monitor_source_dispatch (GSource *source, GSourceFunc callback, gpointer user_data) { GFileMonitorSource *fms = (GFileMonitorSource *) source; QueuedEvent *event; GQueue event_queue; gint64 now; /* make sure the monitor still exists */ if (!fms->instance) return FALSE; now = g_source_get_time (source); /* Acquire the lock once and grab all events in one go, handling the * queued events first. This avoids strange possibilities in cases of * long delays, such as CHANGED events coming before CREATED events. * * We do this by converting the applicable pending changes into queued * events (after the ones already queued) and then stealing the entire * event queue in one go. */ g_mutex_lock (&fms->lock); /* Create events for any pending changes that are due to fire */ while (g_sequence_get_length (fms->pending_changes)) { GSequenceIter *iter = g_sequence_get_begin_iter (fms->pending_changes); PendingChange *pending = g_sequence_get (iter); /* We've gotten to a pending change that's not ready. Stop. */ if (pending_change_get_ready_time (pending, fms) > now) break; if (pending->dirty) { /* It's time to send another CHANGED and update the record */ g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGED, pending->child, NULL); pending->last_emission = now; pending->dirty = FALSE; g_sequence_sort_changed (iter, pending_change_compare_ready_time, fms); } else { /* It's time to send CHANGES_DONE and remove the pending record */ g_file_monitor_source_queue_event (fms, G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT, pending->child, NULL); g_file_monitor_source_remove_pending_change (fms, iter, pending->child); } } /* Steal the queue */ memcpy (&event_queue, &fms->event_queue, sizeof event_queue); memset (&fms->event_queue, 0, sizeof fms->event_queue); g_file_monitor_source_update_ready_time (fms); g_mutex_unlock (&fms->lock); /* We now have our list of events to deliver */ while ((event = g_queue_pop_head (&event_queue))) { /* an event handler could destroy 'instance', so check each time */ if (fms->instance) g_file_monitor_emit_event (fms->instance, event->child, event->other, event->event_type); queued_event_free (event); } return TRUE; } static void g_file_monitor_source_dispose (GFileMonitorSource *fms) { g_mutex_lock (&fms->lock); if (fms->instance) { GHashTableIter iter; gpointer seqiter; QueuedEvent *event; g_hash_table_iter_init (&iter, fms->pending_changes_table); while (g_hash_table_iter_next (&iter, NULL, &seqiter)) { g_hash_table_iter_remove (&iter); g_sequence_remove (seqiter); } while ((event = g_queue_pop_head (&fms->event_queue))) queued_event_free (event); g_assert (g_sequence_get_length (fms->pending_changes) == 0); g_assert (g_hash_table_size (fms->pending_changes_table) == 0); g_assert (fms->event_queue.length == 0); fms->instance = NULL; g_file_monitor_source_update_ready_time (fms); } g_mutex_unlock (&fms->lock); g_source_destroy ((GSource *) fms); } static void g_file_monitor_source_finalize (GSource *source) { GFileMonitorSource *fms = (GFileMonitorSource *) source; /* should already have been cleared in dispose of the monitor */ g_assert (fms->instance == NULL); g_assert (g_sequence_get_length (fms->pending_changes) == 0); g_assert (g_hash_table_size (fms->pending_changes_table) == 0); g_assert (fms->event_queue.length == 0); g_hash_table_unref (fms->pending_changes_table); g_sequence_free (fms->pending_changes); g_free (fms->dirname); g_free (fms->basename); g_free (fms->filename); g_mutex_clear (&fms->lock); } static guint str_hash0 (gconstpointer str) { return str ? g_str_hash (str) : 0; } static gboolean str_equal0 (gconstpointer a, gconstpointer b) { return g_strcmp0 (a, b) == 0; } static GFileMonitorSource * g_file_monitor_source_new (gpointer instance, const gchar *filename, gboolean is_directory, GFileMonitorFlags flags) { static GSourceFuncs source_funcs = { NULL, NULL, g_file_monitor_source_dispatch, g_file_monitor_source_finalize }; GFileMonitorSource *fms; GSource *source; source = g_source_new (&source_funcs, sizeof (GFileMonitorSource)); fms = (GFileMonitorSource *) source; g_mutex_init (&fms->lock); fms->instance = instance; fms->pending_changes = g_sequence_new (pending_change_free); fms->pending_changes_table = g_hash_table_new (str_hash0, str_equal0); fms->rate_limit = DEFAULT_RATE_LIMIT; fms->flags = flags; if (is_directory) { fms->dirname = g_strdup (filename); fms->basename = NULL; fms->filename = NULL; } else if (flags & G_FILE_MONITOR_WATCH_HARD_LINKS) { fms->dirname = NULL; fms->basename = NULL; fms->filename = g_strdup (filename); } else { fms->dirname = g_path_get_dirname (filename); fms->basename = g_path_get_basename (filename); fms->filename = NULL; } return fms; } G_DEFINE_ABSTRACT_TYPE (GLocalFileMonitor, g_local_file_monitor, G_TYPE_FILE_MONITOR) enum { PROP_0, PROP_RATE_LIMIT, }; static void g_local_file_monitor_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec) { GLocalFileMonitor *monitor = G_LOCAL_FILE_MONITOR (object); gint64 rate_limit; g_assert (prop_id == PROP_RATE_LIMIT); rate_limit = g_file_monitor_source_get_rate_limit (monitor->source); rate_limit /= G_TIME_SPAN_MILLISECOND; g_value_set_int (value, rate_limit); } static void g_local_file_monitor_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec) { GLocalFileMonitor *monitor = G_LOCAL_FILE_MONITOR (object); gint64 rate_limit; g_assert (prop_id == PROP_RATE_LIMIT); rate_limit = g_value_get_int (value); rate_limit *= G_TIME_SPAN_MILLISECOND; if (g_file_monitor_source_set_rate_limit (monitor->source, rate_limit)) g_object_notify (object, "rate-limit"); } #ifndef G_OS_WIN32 static void g_local_file_monitor_mounts_changed (GUnixMountMonitor *mount_monitor, gpointer user_data) { GLocalFileMonitor *local_monitor = user_data; GUnixMountEntry *mount; gboolean is_mounted; GFile *file; /* Emulate unmount detection */ mount = g_unix_mount_at (local_monitor->source->dirname, NULL); is_mounted = mount != NULL; if (mount) g_unix_mount_free (mount); if (local_monitor->was_mounted != is_mounted) { if (local_monitor->was_mounted && !is_mounted) { file = g_file_new_for_path (local_monitor->source->dirname); g_file_monitor_emit_event (G_FILE_MONITOR (local_monitor), file, NULL, G_FILE_MONITOR_EVENT_UNMOUNTED); g_object_unref (file); } local_monitor->was_mounted = is_mounted; } } #endif static void g_local_file_monitor_start (GLocalFileMonitor *local_monitor, const gchar *filename, gboolean is_directory, GFileMonitorFlags flags, GMainContext *context) { GLocalFileMonitorClass *class = G_LOCAL_FILE_MONITOR_GET_CLASS (local_monitor); GFileMonitorSource *source; g_return_if_fail (G_IS_LOCAL_FILE_MONITOR (local_monitor)); g_assert (!local_monitor->source); if (is_directory && !class->mount_notify && (flags & G_FILE_MONITOR_WATCH_MOUNTS)) { #ifdef G_OS_WIN32 /*claim everything was mounted */ local_monitor->was_mounted = TRUE; #else GUnixMountEntry *mount; /* Emulate unmount detection */ mount = g_unix_mount_at (local_monitor->source->dirname, NULL); local_monitor->was_mounted = mount != NULL; if (mount) g_unix_mount_free (mount); local_monitor->mount_monitor = g_unix_mount_monitor_get (); g_signal_connect_object (local_monitor->mount_monitor, "mounts-changed", G_CALLBACK (g_local_file_monitor_mounts_changed), local_monitor, 0); #endif } source = g_file_monitor_source_new (local_monitor, filename, is_directory, flags); local_monitor->source = source; /* owns the ref */ G_LOCAL_FILE_MONITOR_GET_CLASS (local_monitor)->start (local_monitor, source->dirname, source->basename, source->filename, source); g_source_attach ((GSource *) source, context); } static void g_local_file_monitor_dispose (GObject *object) { GLocalFileMonitor *local_monitor = G_LOCAL_FILE_MONITOR (object); g_file_monitor_source_dispose (local_monitor->source); G_OBJECT_CLASS (g_local_file_monitor_parent_class)->dispose (object); } static void g_local_file_monitor_finalize (GObject *object) { GLocalFileMonitor *local_monitor = G_LOCAL_FILE_MONITOR (object); g_source_unref ((GSource *) local_monitor->source); G_OBJECT_CLASS (g_local_file_monitor_parent_class)->finalize (object); } static void g_local_file_monitor_init (GLocalFileMonitor* local_monitor) { } static void g_local_file_monitor_class_init (GLocalFileMonitorClass *class) { GObjectClass *gobject_class = G_OBJECT_CLASS (class); gobject_class->get_property = g_local_file_monitor_get_property; gobject_class->set_property = g_local_file_monitor_set_property; gobject_class->dispose = g_local_file_monitor_dispose; gobject_class->finalize = g_local_file_monitor_finalize; g_object_class_override_property (gobject_class, PROP_RATE_LIMIT, "rate-limit"); } static GLocalFileMonitor * g_local_file_monitor_new (gboolean is_remote_fs, GError **error) { GType type = G_TYPE_INVALID; if (is_remote_fs) type = _g_io_module_get_default_type (G_NFS_FILE_MONITOR_EXTENSION_POINT_NAME, "GIO_USE_FILE_MONITOR", G_STRUCT_OFFSET (GLocalFileMonitorClass, is_supported)); if (type == G_TYPE_INVALID) type = _g_io_module_get_default_type (G_LOCAL_FILE_MONITOR_EXTENSION_POINT_NAME, "GIO_USE_FILE_MONITOR", G_STRUCT_OFFSET (GLocalFileMonitorClass, is_supported)); if (type == G_TYPE_INVALID) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Unable to find default local file monitor type")); return NULL; } return g_object_new (type, NULL); } GFileMonitor * g_local_file_monitor_new_for_path (const gchar *pathname, gboolean is_directory, GFileMonitorFlags flags, GError **error) { GLocalFileMonitor *monitor; gboolean is_remote_fs; is_remote_fs = g_local_file_is_remote (pathname); monitor = g_local_file_monitor_new (is_remote_fs, error); if (monitor) g_local_file_monitor_start (monitor, pathname, is_directory, flags, g_main_context_get_thread_default ()); return G_FILE_MONITOR (monitor); } GFileMonitor * g_local_file_monitor_new_in_worker (const gchar *pathname, gboolean is_directory, GFileMonitorFlags flags, GFileMonitorCallback callback, gpointer user_data, GError **error) { GLocalFileMonitor *monitor; gboolean is_remote_fs; is_remote_fs = g_local_file_is_remote (pathname); monitor = g_local_file_monitor_new (is_remote_fs, error); if (monitor) { if (callback) g_signal_connect (monitor, "changed", G_CALLBACK (callback), user_data); g_local_file_monitor_start (monitor, pathname, is_directory, flags, GLIB_PRIVATE_CALL(g_get_worker_context) ()); } return G_FILE_MONITOR (monitor); }