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-rw-r--r--src/InotifySource.cxx173
1 files changed, 173 insertions, 0 deletions
diff --git a/src/InotifySource.cxx b/src/InotifySource.cxx
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index 000000000..16fd62511
--- /dev/null
+++ b/src/InotifySource.cxx
@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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.
+ */
+
+#include "config.h"
+#include "InotifySource.hxx"
+
+extern "C" {
+#include "fifo_buffer.h"
+}
+
+#include "fd_util.h"
+#include "mpd_error.h"
+
+#include <glib.h>
+
+#include <sys/inotify.h>
+#include <unistd.h>
+#include <errno.h>
+
+#undef G_LOG_DOMAIN
+#define G_LOG_DOMAIN "inotify"
+
+struct mpd_inotify_source {
+ int fd;
+
+ GIOChannel *channel;
+
+ /**
+ * The channel's source id in the GLib main loop.
+ */
+ guint id;
+
+ struct fifo_buffer *buffer;
+
+ mpd_inotify_callback_t callback;
+ void *callback_ctx;
+};
+
+/**
+ * A GQuark for GError instances.
+ */
+static inline GQuark
+mpd_inotify_quark(void)
+{
+ return g_quark_from_static_string("inotify");
+}
+
+static gboolean
+mpd_inotify_in_event(G_GNUC_UNUSED GIOChannel *_source,
+ G_GNUC_UNUSED GIOCondition condition,
+ gpointer data)
+{
+ struct mpd_inotify_source *source = (struct mpd_inotify_source *)data;
+ void *dest;
+ size_t length;
+ ssize_t nbytes;
+
+ dest = fifo_buffer_write(source->buffer, &length);
+ if (dest == NULL)
+ MPD_ERROR("buffer full");
+
+ nbytes = read(source->fd, dest, length);
+ if (nbytes < 0)
+ MPD_ERROR("failed to read from inotify: %s",
+ g_strerror(errno));
+ if (nbytes == 0)
+ MPD_ERROR("end of file from inotify");
+
+ fifo_buffer_append(source->buffer, nbytes);
+
+ while (true) {
+ const char *name;
+
+ const struct inotify_event *event =
+ (const struct inotify_event *)
+ fifo_buffer_read(source->buffer, &length);
+ if (event == NULL || length < sizeof(*event) ||
+ length < sizeof(*event) + event->len)
+ break;
+
+ if (event->len > 0 && event->name[event->len - 1] == 0)
+ name = event->name;
+ else
+ name = NULL;
+
+ source->callback(event->wd, event->mask, name,
+ source->callback_ctx);
+ fifo_buffer_consume(source->buffer,
+ sizeof(*event) + event->len);
+ }
+
+ return true;
+}
+
+struct mpd_inotify_source *
+mpd_inotify_source_new(mpd_inotify_callback_t callback, void *callback_ctx,
+ GError **error_r)
+{
+ struct mpd_inotify_source *source =
+ g_new(struct mpd_inotify_source, 1);
+
+ source->fd = inotify_init_cloexec();
+ if (source->fd < 0) {
+ g_set_error(error_r, mpd_inotify_quark(), errno,
+ "inotify_init() has failed: %s",
+ g_strerror(errno));
+ g_free(source);
+ return NULL;
+ }
+
+ source->buffer = fifo_buffer_new(4096);
+
+ source->channel = g_io_channel_unix_new(source->fd);
+ source->id = g_io_add_watch(source->channel, G_IO_IN,
+ mpd_inotify_in_event, source);
+
+ source->callback = callback;
+ source->callback_ctx = callback_ctx;
+
+ return source;
+}
+
+void
+mpd_inotify_source_free(struct mpd_inotify_source *source)
+{
+ g_source_remove(source->id);
+ g_io_channel_unref(source->channel);
+ fifo_buffer_free(source->buffer);
+ close(source->fd);
+ g_free(source);
+}
+
+int
+mpd_inotify_source_add(struct mpd_inotify_source *source,
+ const char *path_fs, unsigned mask,
+ GError **error_r)
+{
+ int wd = inotify_add_watch(source->fd, path_fs, mask);
+ if (wd < 0)
+ g_set_error(error_r, mpd_inotify_quark(), errno,
+ "inotify_add_watch() has failed: %s",
+ g_strerror(errno));
+
+ return wd;
+}
+
+void
+mpd_inotify_source_rm(struct mpd_inotify_source *source, unsigned wd)
+{
+ int ret = inotify_rm_watch(source->fd, wd);
+ if (ret < 0 && errno != EINVAL)
+ g_warning("inotify_rm_watch() has failed: %s",
+ g_strerror(errno));
+
+ /* EINVAL may happen here when the file has been deleted; the
+ kernel seems to auto-unregister deleted files */
+}