decoder/mad: remove option "gapless", always do gapless

Why would anybody want to keep the silence inserted by the codec?
Other plugins/codecs (such as Vorbis) have this hard-coded as well.

NEWS

@@ -10,6 +10,7 @@ ver 0.22 (not yet released)
 * archive
   - iso9660: support seeking
 * decoder
+  - mad: remove option "gapless", always do gapless
   - sidplay: add option "default_genre"
   - sidplay: map SID name field to "Album" tag
 * filter

doc/plugins.rst

@@ -406,15 +406,6 @@ plugin should be enabled only if you have a bit-perfect playback path
 to a DSD-capable DAC; for everybody else, playing back the ALAC copy
 of the file is better.
 
-.. list-table::
-   :widths: 20 80
-   :header-rows: 1
-
-   * - Setting
-     - Description
-   * - **gapless yes|no**
-     - This specifies whether to support gapless playback of MP3s which have the necessary headers. Useful if your MP3s have headers with incorrect information. If you have such MP3s, it is highly recommended that you fix them using `vbrfix <http://www.willwap.co.uk/Programs/vbrfix.php>`_ instead of disabling gapless MP3 playback. The default is to support gapless MP3 playback.
-
 mad
 ---
 

src/config/Migrate.cxx

@@ -55,17 +55,8 @@ MigrateCurlProxyConfig(ConfigData &config) noexcept
 				 "proxy_password");
 }
 
-static void
-MigrateMadConfig(ConfigData &config) noexcept
-{
-	MigrateParamToBlockParam(config, ConfigOption::GAPLESS_MP3_PLAYBACK,
-				 ConfigBlockOption::DECODER, "plugin", "mad",
-				 "gapless");
-}
-
 void
 Migrate(ConfigData &config) noexcept
 {
 	MigrateCurlProxyConfig(config);
-	MigrateMadConfig(config);
 }

src/decoder/plugins/MadDecoderPlugin.cxx

@@ -62,12 +62,8 @@ enum class MadDecoderMuteFrame {
 /* the number of samples of silence the decoder inserts at start */
 static constexpr unsigned DECODERDELAY = 529;
 
-static constexpr bool DEFAULT_GAPLESS_MP3_PLAYBACK = true;
-
 static constexpr Domain mad_domain("mad");
 
-static bool gapless_playback;
-
 gcc_const
 static SongTime
 ToSongTime(mad_timer_t t) noexcept
@@ -100,14 +96,6 @@ mad_fixed_to_24_buffer(int32_t *dest, const struct mad_pcm &src,
 			*dest++ = mad_fixed_to_24_sample(src.samples[c][i]);
 }
 
-static bool
-mad_plugin_init(const ConfigBlock &block)
-{
-	gapless_playback = block.GetBlockValue("gapless",
-					       DEFAULT_GAPLESS_MP3_PLAYBACK);
-	return true;
-}
-
 class MadDecoder {
 	static constexpr size_t READ_BUFFER_SIZE = 40960;
 
@@ -735,7 +723,7 @@ MadDecoder::DecodeFirstFrame(Tag *tag) noexcept
 
 		struct lame lame;
 		if (parse_lame(&lame, &ptr, &bitlen)) {
-			if (gapless_playback && input_stream.IsSeekable()) {
+			if (input_stream.IsSeekable()) {
 				/* libmad inserts 529 samples of
 				   silence at the beginning and
 				   removes those 529 samples at the
@@ -1030,6 +1018,5 @@ static const char *const mad_mime_types[] = { "audio/mpeg", nullptr };
 
 constexpr DecoderPlugin mad_decoder_plugin =
 	DecoderPlugin("mad", mad_decode, mad_decoder_scan_stream)
-	.WithInit(mad_plugin_init)
 	.WithSuffixes(mad_suffixes)
 	.WithMimeTypes(mad_mime_types);