diff --git a/doc/protocol.xml b/doc/protocol.xml
index 7b384e4da..f68375c6b 100644
--- a/doc/protocol.xml
+++ b/doc/protocol.xml
@@ -276,6 +276,12 @@
+
+
+ "(!EXPRESSION)
": negate an expression.
+
+
+
"(EXPRESSION1 AND EXPRESSION2 ...)
": combine two or
diff --git a/src/song/Filter.cxx b/src/song/Filter.cxx
index e9d978dd5..c96ecb8dc 100644
--- a/src/song/Filter.cxx
+++ b/src/song/Filter.cxx
@@ -19,6 +19,7 @@
#include "config.h"
#include "Filter.hxx"
+#include "NotSongFilter.hxx"
#include "UriSongFilter.hxx"
#include "BaseSongFilter.hxx"
#include "TagSongFilter.hxx"
@@ -214,6 +215,20 @@ SongFilter::ParseExpression(const char *&s, bool fold_case)
}
}
+ if (*s == '!') {
+ s = StripLeft(s + 1);
+
+ if (*s != '(')
+ throw std::runtime_error("'(' expected");
+
+ auto inner = ParseExpression(s, fold_case);
+ if (*s != ')')
+ throw std::runtime_error("')' expected");
+ s = StripLeft(s + 1);
+
+ return std::make_unique(std::move(inner));
+ }
+
auto type = ExpectFilterType(s);
if (type == LOCATE_TAG_MODIFIED_SINCE) {
diff --git a/src/song/NotSongFilter.hxx b/src/song/NotSongFilter.hxx
new file mode 100644
index 000000000..000ac1f69
--- /dev/null
+++ b/src/song/NotSongFilter.hxx
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2003-2018 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.
+ */
+
+#ifndef MPD_NOT_SONG_FILTER_HXX
+#define MPD_NOT_SONG_FILTER_HXX
+
+#include "ISongFilter.hxx"
+
+/**
+ * Negate an #ISongFilter.
+ */
+class NotSongFilter final : public ISongFilter {
+ ISongFilterPtr child;
+
+public:
+ template
+ explicit NotSongFilter(C &&_child) noexcept
+ :child(std::forward(_child)) {}
+
+ /* virtual methods from ISongFilter */
+ ISongFilterPtr Clone() const noexcept override {
+ return std::make_unique(child->Clone());
+ }
+
+ std::string ToExpression() const noexcept override {
+ return "(!" + child->ToExpression() + ")";
+ }
+
+ bool Match(const LightSong &song) const noexcept override {
+ return !child->Match(song);
+ }
+};
+
+#endif