util/{Const,Writable}Buffer, ...: rename IsEmpty() to empty(), imitating STL

src/decoder/Bridge.cxx

@@ -496,7 +496,7 @@ DecoderBridge::SubmitData(InputStream *is,
 				     SongTime::FromS(timestamp) -
 				     dc.song->GetStartTime(),
 				     kbit_rate);
-		if (dest.IsEmpty()) {
+		if (dest.empty()) {
 			/* the chunk is full, flush it */
 			FlushChunk();
 			continue;

src/decoder/DecoderBuffer.cxx

@@ -25,7 +25,7 @@ bool
 DecoderBuffer::Fill()
 {
 	auto w = buffer.Write();
-	if (w.IsEmpty())
+	if (w.empty())
 		/* buffer is full */
 		return false;
 

src/decoder/plugins/FaadDecoderPlugin.cxx

@@ -127,7 +127,7 @@ adts_song_duration(DecoderBuffer &buffer)
 
 		if (frames == 0) {
 			auto data = ConstBuffer<uint8_t>::FromVoid(buffer.Read());
-			assert(!data.IsEmpty());
+			assert(!data.empty());
 			assert(frame_length <= data.size);
 
 			sample_rate = adts_sample_rates[(data.data[2] & 0x3c) >> 2];
@@ -255,7 +255,7 @@ faad_decoder_init(NeAACDecHandle decoder, DecoderBuffer &buffer,
 		  AudioFormat &audio_format)
 {
 	auto data = ConstBuffer<uint8_t>::FromVoid(buffer.Read());
-	if (data.IsEmpty())
+	if (data.empty())
 		throw std::runtime_error("Empty file");
 
 	uint8_t channels;
@@ -283,7 +283,7 @@ faad_decoder_decode(NeAACDecHandle decoder, DecoderBuffer &buffer,
 		    NeAACDecFrameInfo *frame_info)
 {
 	auto data = ConstBuffer<uint8_t>::FromVoid(buffer.Read());
-	if (data.IsEmpty())
+	if (data.empty())
 		return nullptr;
 
 	return NeAACDecDecode(decoder, frame_info,

src/decoder/plugins/FfmpegDecoderPlugin.cxx

@@ -617,7 +617,7 @@ FfmpegCheckTag(DecoderClient &client, InputStream &is,
 
 	TagBuilder tag;
 	FfmpegScanTag(format_context, audio_stream, tag);
-	if (!tag.IsEmpty())
+	if (!tag.empty())
 		client.SubmitTag(is, tag.Commit());
 }
 

src/decoder/plugins/FlacMetadata.cxx

@@ -97,7 +97,7 @@ flac_scan_comment(const FLAC__StreamMetadata_VorbisComment_Entry *entry,
 	if (handler.pair != nullptr) {
 		const char *comment = (const char *)entry->entry;
 		const DivideString split(comment, '=');
-		if (split.IsDefined() && !split.IsEmpty())
+		if (split.IsDefined() && !split.empty())
 			tag_handler_invoke_pair(handler, handler_ctx,
 						split.GetFirst(),
 						split.GetSecond());

src/decoder/plugins/OpusDecoderPlugin.cxx

@@ -211,7 +211,7 @@ MPDOpusDecoder::HandleTags(const ogg_packet &packet)
 	if (ScanOpusTags(packet.packet, packet.bytes,
 			 &rgi,
 			 add_tag_handler, &tag_builder) &&
-	    !tag_builder.IsEmpty()) {
+	    !tag_builder.empty()) {
 		client.SubmitReplayGain(&rgi);
 
 		Tag tag = tag_builder.Commit();

src/decoder/plugins/PcmDecoderPlugin.cxx

@@ -44,7 +44,7 @@ FillBuffer(DecoderClient &client, InputStream &is, B &buffer)
 {
 	buffer.Shift();
 	auto w = buffer.Write();
-	if (w.IsEmpty())
+	if (w.empty())
 		return true;
 
 	size_t nbytes = decoder_read(client, is, w.data, w.size);
@@ -185,7 +185,7 @@ pcm_stream_decode(DecoderClient &client, InputStream &is)
 			r.size = (r.size / 3) * 4;
 		}
 
-		cmd = !r.IsEmpty()
+		cmd = !r.empty()
 			? client.SubmitData(is, r.data, r.size, 0)
 			: client.GetCommand();
 		if (cmd == DecoderCommand::SEEK) {