input/curl: move code to IcyInputStream

Makefile.am

@@ -1065,6 +1065,7 @@ endif
 
 if ENABLE_CURL
 libinput_a_SOURCES += \
+	src/input/IcyInputStream.cxx src/input/IcyInputStream.hxx \
 	src/input/plugins/CurlInputPlugin.cxx src/input/plugins/CurlInputPlugin.hxx \
 	src/IcyMetaDataParser.cxx src/IcyMetaDataParser.hxx
 endif

src/IcyMetaDataParser.cxx

@@ -220,3 +220,32 @@ IcyMetaDataParser::Meta(const void *data, size_t length)
 
 	return length;
 }
+
+size_t
+IcyMetaDataParser::ParseInPlace(void *data, size_t length)
+{
+	uint8_t *const dest0 = (uint8_t *)data;
+	uint8_t *dest = dest0;
+	const uint8_t *src = dest0;
+
+	while (length > 0) {
+		size_t chunk = Data(length);
+		if (chunk > 0) {
+			memmove(dest, src, chunk);
+			dest += chunk;
+			src += chunk;
+			length -= chunk;
+
+			if (length == 0)
+				break;
+		}
+
+		chunk = Meta(src, length);
+		if (chunk > 0) {
+			src += chunk;
+			length -= chunk;
+		}
+	}
+
+	return dest - dest0;
+}

src/IcyMetaDataParser.hxx

@@ -75,6 +75,13 @@ public:
 	 */
 	size_t Meta(const void *data, size_t length);
 
+	/**
+	 * Parse data and eliminate metadata.
+	 *
+	 * @return the number of data bytes remaining in the buffer
+	 */
+	size_t ParseInPlace(void *data, size_t length);
+
 	Tag *ReadTag() {
 		Tag *result = tag;
 		tag = nullptr;

src/input/IcyInputStream.cxx

@@ -0,0 +1,99 @@
+/*
+ * 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 "IcyInputStream.hxx"
+#include "tag/Tag.hxx"
+
+IcyInputStream::IcyInputStream(InputStream *_input)
+	:ProxyInputStream(_input),
+	 input_tag(nullptr), icy_tag(nullptr),
+	 override_offset(0)
+{
+}
+
+IcyInputStream::~IcyInputStream()
+{
+	delete input_tag;
+	delete icy_tag;
+}
+
+void
+IcyInputStream::Update()
+{
+	ProxyInputStream::Update();
+
+	if (IsEnabled())
+		offset = override_offset;
+}
+
+Tag *
+IcyInputStream::ReadTag()
+{
+	Tag *new_input_tag = ProxyInputStream::ReadTag();
+	if (!IsEnabled())
+		return new_input_tag;
+
+	if (new_input_tag != nullptr) {
+		delete input_tag;
+		input_tag = new_input_tag;
+	}
+
+	Tag *new_icy_tag = parser.ReadTag();
+	if (new_icy_tag != nullptr) {
+		delete icy_tag;
+		icy_tag = new_icy_tag;
+	}
+
+	if (new_input_tag == nullptr && new_icy_tag == nullptr)
+		/* no change */
+		return nullptr;
+
+	if (input_tag == nullptr && icy_tag == nullptr)
+		/* no tag */
+		return nullptr;
+
+	if (input_tag == nullptr)
+		return new Tag(*icy_tag);
+
+	if (icy_tag == nullptr)
+		return new Tag(*input_tag);
+
+	return Tag::Merge(*input_tag, *icy_tag);
+}
+
+size_t
+IcyInputStream::Read(void *ptr, size_t read_size, Error &error)
+{
+	if (!IsEnabled())
+		return ProxyInputStream::Read(ptr, read_size, error);
+
+	while (true) {
+		size_t nbytes = ProxyInputStream::Read(ptr, read_size, error);
+		if (nbytes == 0)
+			return 0;
+
+		size_t result = parser.ParseInPlace(ptr, nbytes);
+		if (result > 0) {
+			override_offset += result;
+			offset = override_offset;
+			return result;
+		}
+	}
+}

src/input/IcyInputStream.hxx

@@ -0,0 +1,67 @@
+/*
+ * 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.
+ */
+
+#ifndef MPD_ICY_INPUT_STREAM_HXX
+#define MPD_ICY_INPUT_STREAM_HXX
+
+#include "ProxyInputStream.hxx"
+#include "IcyMetaDataParser.hxx"
+
+struct Tag;
+
+/**
+ * An #InputStream filter that parses Icy metadata.
+ */
+class IcyInputStream final : public ProxyInputStream {
+	IcyMetaDataParser parser;
+
+	/**
+	 * The #Tag object ready to be requested via ReadTag().
+	 */
+	Tag *input_tag;
+
+	/**
+	 * The #Tag object ready to be requested via ReadTag().
+	 */
+	Tag *icy_tag;
+
+	offset_type override_offset;
+
+public:
+	IcyInputStream(InputStream *_input);
+	virtual ~IcyInputStream();
+
+	IcyInputStream(const IcyInputStream &) = delete;
+	IcyInputStream &operator=(const IcyInputStream &) = delete;
+
+	void Enable(size_t _data_size) {
+		parser.Start(_data_size);
+	}
+
+	bool IsEnabled() const {
+		return parser.IsDefined();
+	}
+
+	/* virtual methods from InputStream */
+	void Update() override;
+	Tag *ReadTag() override;
+	size_t Read(void *ptr, size_t size, Error &error) override;
+};
+
+#endif

src/input/plugins/CurlInputPlugin.cxx

@@ -19,13 +19,13 @@
 
 #include "config.h"
 #include "CurlInputPlugin.hxx"
+#include "../IcyInputStream.hxx"
 #include "../InputStream.hxx"
 #include "../InputPlugin.hxx"
 #include "config/ConfigGlobal.hxx"
 #include "config/ConfigData.hxx"
 #include "tag/Tag.hxx"
 #include "tag/TagBuilder.hxx"
-#include "IcyMetaDataParser.hxx"
 #include "event/SocketMonitor.hxx"
 #include "event/TimeoutMonitor.hxx"
 #include "event/Call.hxx"
@@ -93,10 +93,7 @@ struct CurlInputStream final : public InputStream {
 	char error_buffer[CURL_ERROR_SIZE];
 
 	/** parser for icy-metadata */
-	IcyMetaDataParser icy;
-
-	/** the stream name from the icy-name response header */
-	std::string meta_name;
+	IcyInputStream *icy;
 
 	/** the tag object ready to be requested via
 	    InputStream::ReadTag() */
@@ -110,6 +107,7 @@ struct CurlInputStream final : public InputStream {
 		 request_headers(nullptr),
 		 buffer((uint8_t *)_buffer, CURL_MAX_BUFFERED),
 		 paused(false),
+		 icy(new IcyInputStream(this)),
 		 tag(nullptr) {}
 
 	~CurlInputStream();
@@ -155,8 +153,6 @@ struct CurlInputStream final : public InputStream {
 		return buffer.GetSize();
 	}
 
-	void CopyIcyTag();
-
 	/**
 	 * A HTTP request is finished.
 	 *
@@ -683,83 +679,19 @@ CurlInputStream::FillBuffer(Error &error)
 	return !buffer.IsEmpty();
 }
 
-static size_t
-read_from_buffer(IcyMetaDataParser &icy, CircularBuffer<uint8_t> &buffer,
-		 void *dest0, size_t length)
-{
-	uint8_t *dest = (uint8_t *)dest0;
-	size_t nbytes = 0;
-
-	while (true) {
-		auto r = buffer.Read();
-		if (r.IsEmpty())
-			break;
-
-		if (r.size > length)
-			r.size = length;
-
-		size_t chunk = icy.Data(r.size);
-		if (chunk > 0) {
-			memcpy(dest, r.data, chunk);
-			buffer.Consume(chunk);
-
-			nbytes += chunk;
-			dest += chunk;
-			length -= chunk;
-
-			if (length == 0)
-				break;
-		}
-
-		r = buffer.Read();
-		if (r.IsEmpty())
-			break;
-
-		chunk = icy.Meta(r.data, r.size);
-		if (chunk > 0) {
-			buffer.Consume(chunk);
-			if (length == 0)
-				break;
-		}
-	}
-
-	return nbytes;
-}
-
-inline void
-CurlInputStream::CopyIcyTag()
-{
-	Tag *new_tag = icy.ReadTag();
-	if (new_tag == nullptr)
-		return;
-
-	delete tag;
-
-	if (!meta_name.empty() && !new_tag->HasType(TAG_NAME)) {
-		TagBuilder tag_builder(std::move(*new_tag));
-		tag_builder.AddItem(TAG_NAME, meta_name.c_str());
-		*new_tag = tag_builder.Commit();
-	}
-
-	tag = new_tag;
-}
-
 size_t
 CurlInputStream::Read(void *ptr, size_t read_size, Error &error)
 {
-	size_t nbytes;
+	if (!FillBuffer(error))
+		return 0;
 
-	do {
-		/* fill the buffer */
+	auto r = buffer.Read();
+	if (r.IsEmpty())
+		return 0;
 
-		if (!FillBuffer(error))
-			return 0;
-
-		nbytes = read_from_buffer(icy, buffer, ptr, read_size);
-	} while (nbytes == 0);
-
-	if (icy.IsDefined())
-		CopyIcyTag();
+	const size_t nbytes = std::min(read_size, r.size);
+	memcpy(ptr, r.data, nbytes);
+	buffer.Consume(nbytes);
 
 	offset += (InputPlugin::offset_type)nbytes;
 
@@ -781,7 +713,7 @@ CurlInputStream::HeaderReceived(const char *name, std::string &&value)
 {
 	if (StringEqualsCaseASCII(name, "accept-ranges")) {
 		/* a stream with icy-metadata is not seekable */
-		if (!icy.IsDefined())
+		if (!icy->IsEnabled())
 			seekable = true;
 	} else if (StringEqualsCaseASCII(name, "content-length")) {
 		size = offset + ParseUint64(value.c_str());
@@ -790,23 +722,21 @@ CurlInputStream::HeaderReceived(const char *name, std::string &&value)
 	} else if (StringEqualsCaseASCII(name, "icy-name") ||
 		   StringEqualsCaseASCII(name, "ice-name") ||
 		   StringEqualsCaseASCII(name, "x-audiocast-name")) {
-		meta_name = std::move(value);
-
 		delete tag;
 
 		TagBuilder tag_builder;
-		tag_builder.AddItem(TAG_NAME, meta_name.c_str());
+		tag_builder.AddItem(TAG_NAME, value.c_str());
 
 		tag = tag_builder.CommitNew();
 	} else if (StringEqualsCaseASCII(name, "icy-metaint")) {
-		if (icy.IsDefined())
+		if (icy->IsEnabled())
 			return;
 
 		size_t icy_metaint = ParseUint64(value.c_str());
 		FormatDebug(curl_domain, "icy-metaint=%zu", icy_metaint);
 
 		if (icy_metaint > 0) {
-			icy.Start(icy_metaint);
+			icy->Enable(icy_metaint);
 
 			/* a stream with icy-metadata is not
 			   seekable */
@@ -1072,7 +1002,7 @@ CurlInputStream::Open(const char *url, Mutex &mutex, Cond &cond,
 		return nullptr;
 	}
 
-	return c;
+	return c->icy;
 }
 
 static InputStream *