1 files changed, 116 insertions, 0 deletions
diff --git a/src/db/update/InotifySource.cxx b/src/db/update/InotifySource.cxx
new file mode 100644
index 000000000..233504ad6
--- /dev/null
+++ b/src/db/update/InotifySource.cxx
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2003-2014 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"
+#include "InotifyDomain.hxx"
+#include "util/Error.hxx"
+#include "system/fd_util.h"
+#include "system/FatalError.hxx"
+#include "Log.hxx"
+
+#include <algorithm>
+
+#include <sys/inotify.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdint.h>
+#include <limits.h>
+
+bool
+InotifySource::OnSocketReady(gcc_unused unsigned flags)
+{
+	uint8_t buffer[4096];
+	static_assert(sizeof(buffer) >= sizeof(struct inotify_event) + NAME_MAX + 1,
+		      "inotify buffer too small");
+
+	ssize_t nbytes = read(Get(), buffer, sizeof(buffer));
+	if (nbytes < 0)
+		FatalSystemError("Failed to read from inotify");
+	if (nbytes == 0)
+		FatalError("end of file from inotify");
+
+	const uint8_t *p = buffer, *const end = p + nbytes;
+
+	while (true) {
+		const size_t remaining = end - p;
+		const struct inotify_event *event =
+			(const struct inotify_event *)p;
+		if (remaining < sizeof(*event) ||
+		    remaining < sizeof(*event) + event->len)
+			break;
+
+		const char *name;
+		if (event->len > 0 && event->name[event->len - 1] == 0)
+			name = event->name;
+		else
+			name = nullptr;
+
+		callback(event->wd, event->mask, name, callback_ctx);
+		p += sizeof(*event) + event->len;
+	}
+
+	return true;
+}
+
+inline
+InotifySource::InotifySource(EventLoop &_loop,
+			     mpd_inotify_callback_t _callback, void *_ctx,
+			     int _fd)
+	:SocketMonitor(_fd, _loop),
+	 callback(_callback), callback_ctx(_ctx)
+{
+	ScheduleRead();
+
+}
+
+InotifySource *
+InotifySource::Create(EventLoop &loop,
+		      mpd_inotify_callback_t callback, void *callback_ctx,
+		      Error &error)
+{
+	int fd = inotify_init_cloexec();
+	if (fd < 0) {
+		error.SetErrno("inotify_init() has failed");
+		return nullptr;
+	}
+
+	return new InotifySource(loop, callback, callback_ctx, fd);
+}
+
+int
+InotifySource::Add(const char *path_fs, unsigned mask, Error &error)
+{
+	int wd = inotify_add_watch(Get(), path_fs, mask);
+	if (wd < 0)
+		error.SetErrno("inotify_add_watch() has failed");
+
+	return wd;
+}
+
+void
+InotifySource::Remove(unsigned wd)
+{
+	int ret = inotify_rm_watch(Get(), wd);
+	if (ret < 0 && errno != EINVAL)
+		LogErrno(inotify_domain, "inotify_rm_watch() has failed");
+
+	/* EINVAL may happen here when the file has been deleted; the
+	   kernel seems to auto-unregister deleted files */
+}