fs/Traits: add PathTraitsUTF8::IsAbsoluteOrHasScheme()

src/fs/Traits.cxx

@@ -19,6 +19,7 @@
 
 #include "Traits.hxx"
 #include "util/StringCompare.hxx"
+#include "util/UriExtract.hxx"
 
 #include <string.h>
 
@@ -220,6 +221,12 @@ PathTraitsUTF8::Build(string_view a, string_view b) noexcept
 	return BuildPathImpl<PathTraitsUTF8>(a, b);
 }
 
+bool
+PathTraitsUTF8::IsAbsoluteOrHasScheme(const_pointer p) noexcept
+{
+	return IsAbsolute(p) || uri_has_scheme(p);
+}
+
 PathTraitsUTF8::const_pointer
 PathTraitsUTF8::GetBase(const_pointer p) noexcept
 {

src/fs/Traits.hxx

@@ -274,6 +274,13 @@ struct PathTraitsUTF8 {
 		return IsSeparator(*p);
 	}
 
+	/**
+	 * Is this any kind of absolute URI? (Unlike IsAbsolute(),
+	 * this includes URIs/URLs with a scheme)
+	 */
+	[[gnu::pure]] [[gnu::nonnull]]
+	static bool IsAbsoluteOrHasScheme(const_pointer p) noexcept;
+
 	gcc_pure gcc_nonnull_all
 	static bool IsSpecialFilename(const_pointer name) noexcept {
 		return (name[0] == '.' && name[1] == 0) ||

src/playlist/PlaylistSong.cxx

@@ -92,8 +92,8 @@ playlist_check_translate_song(DetachedSong &song, std::string_view base_uri,
 	}
 #endif
 
-	if (base_uri.data() != nullptr && !uri_has_scheme(uri) &&
-	    !PathTraitsUTF8::IsAbsolute(uri))
+	if (base_uri.data() != nullptr &&
+	    !PathTraitsUTF8::IsAbsoluteOrHasScheme(uri))
 		song.SetURI(PathTraitsUTF8::Build(base_uri, uri));
 
 	return playlist_check_load_song(song, loader);

src/song/DetachedSong.cxx

@@ -60,7 +60,7 @@ DetachedSong::IsInDatabase() const noexcept
 	   GetRealURI() is never relative */
 
 	const char *_uri = GetURI();
-	return !uri_has_scheme(_uri) && !PathTraitsUTF8::IsAbsolute(_uri);
+	return !PathTraitsUTF8::IsAbsoluteOrHasScheme(_uri);
 }
 
 SignedSongTime