playlist: make kept song count collision resistant

src/browser.cpp

@@ -398,7 +398,7 @@ void Browser::LocateSong(const MPD::Song &s)
 		GetDirectory(s.getDirectory());
 	for (size_t i = 0; i < w.size(); ++i)
 	{
-		if (w[i].value().type == itSong && s.getHash() == w[i].value().song->getHash())
+		if (w[i].value().type == itSong && s == *w[i].value().song)
 		{
 			w.highlight(i);
 			break;
@@ -460,16 +460,7 @@ void Browser::GetDirectory(std::string dir, std::string subdir)
 			}
 			case itSong:
 			{
-				bool bold = 0;
-				for (size_t i = 0; i < myPlaylist->main().size(); ++i)
-				{
-					if (myPlaylist->main().at(i).value().getHash() == it->song->getHash())
-					{
-						bold = 1;
-						break;
-					}
-				}
-				w.addItem(*it, bold);
+				w.addItem(*it, myPlaylist->checkForSong(*it->song));
 				break;
 			}
 		}

src/media_library.cpp

@@ -980,11 +980,11 @@ void MediaLibrary::LocateSong(const MPD::Song &s)
 	if (Songs.empty())
 		update();
 	
-	if (s.getHash() != Songs.current().value().getHash())
+	if (s != Songs.current().value())
 	{
 		for (size_t i = 0; i < Songs.size(); ++i)
 		{
-			if (s.getHash()  == Songs[i].value().getHash())
+			if (s == Songs[i].value())
 			{
 				Songs.highlight(i);
 				break;

src/playlist.cpp

@@ -360,20 +360,20 @@ unsigned Playlist::currentSongLength() const
 
 bool Playlist::checkForSong(const MPD::Song &s)
 {
-	return m_song_hashes.find(s.getHash()) != m_song_hashes.end();
+	return m_song_refs.find(s) != m_song_refs.end();
 }
 
-void Playlist::registerHash(size_t hash)
+void Playlist::registerSong(const MPD::Song &s)
 {
-	++m_song_hashes[hash];
+	++m_song_refs[s];
 }
 
-void Playlist::unregisterHash(size_t hash)
+void Playlist::unregisterSong(const MPD::Song &s)
 {
-	auto it = m_song_hashes.find(hash);
-	assert(it != m_song_hashes.end());
+	auto it = m_song_refs.find(s);
+	assert(it != m_song_refs.end());
 	if (it->second == 1)
-		m_song_hashes.erase(it);
+		m_song_refs.erase(it);
 	else
 		--it->second;
 }

src/playlist.h

@@ -81,8 +81,8 @@ struct Playlist: Screen<NC::Menu<MPD::Song>>, Filterable, HasSongs, Searchable,
 	unsigned currentSongLength() const;
 	
 	bool checkForSong(const MPD::Song &s);
-	void registerHash(size_t hash);
-	void unregisterHash(size_t hash);
+	void registerSong(const MPD::Song &s);
+	void unregisterSong(const MPD::Song &s);
 	
 	void reloadTotalLength() { m_reload_total_length = true; }
 	void reloadRemaining() { m_reload_remaining = true; }
@@ -95,7 +95,7 @@ private:
 
 	std::string m_stats;
 	
-	std::unordered_map<size_t, int> m_song_hashes;
+	std::unordered_map<MPD::Song, int, MPD::Song::Hash> m_song_refs;
 	
 	size_t m_total_length;;
 	size_t m_remaining_time;

src/song.cpp

@@ -30,13 +30,13 @@
 #include "utility/wide_string.h"
 #include "window.h"
 
-namespace {//
+namespace {
 
 size_t calc_hash(const char* s, unsigned seed = 0)
 {
 	size_t hash = seed;
 	while (*s)
-		hash = hash * 101  +  *s++;
+		hash = hash * 101 + *s++;
 	return hash;
 }
 
@@ -211,12 +211,6 @@ std::string MPD::Song::getTags(GetFunction f, const std::string &tags_separator)
 	return result;
 }
 
-unsigned Song::getHash() const
-{
-	assert(m_song);
-	return m_hash;
-}
-
 unsigned Song::getDuration() const
 {
 	assert(m_song);

src/song.h

@@ -21,6 +21,7 @@
 #ifndef NCMPCPP_SONG_H
 #define NCMPCPP_SONG_H
 
+#include <cstring>
 #include <functional>
 #include <memory>
 #include <string>
@@ -32,6 +33,10 @@ namespace MPD {//
 
 struct Song
 {
+	struct Hash {
+		size_t operator()(const Song &s) const { return s.m_hash; }
+	};
+
 	typedef std::string (Song::*GetFunction)(unsigned) const;
 	
 	Song() { }
@@ -61,7 +66,6 @@ struct Song
 	
 	virtual std::string getTags(GetFunction f, const std::string &tags_separator) const;
 	
-	virtual unsigned getHash() const;
 	virtual unsigned getDuration() const;
 	virtual unsigned getPosition() const;
 	virtual unsigned getID() const;
@@ -76,9 +80,19 @@ struct Song
 	virtual std::string toString(const std::string &fmt, const std::string &tags_separator,
 	                             const std::string &escape_chars = "") const;
 	
-	bool operator==(const Song &rhs) const { return m_hash == rhs.m_hash; }
-	bool operator!=(const Song &rhs) const { return m_hash != rhs.m_hash; }
+	bool operator==(const Song &rhs) const {
+		if (m_hash != rhs.m_hash)
+			return false;
+		return strcmp(c_uri(), rhs.c_uri()) == 0;
+	}
+	bool operator!=(const Song &rhs) const {
+		if (m_hash != rhs.m_hash)
+			return true;
+		return strcmp(c_uri(), rhs.c_uri()) != 0;
+	}
 	
+	const char *c_uri() const { return m_song ? mpd_song_get_uri(m_song.get()) : ""; }
+
 	static std::string ShowTime(unsigned length);
 	static void validateFormat(const std::string &fmt);
 	

src/status.cpp

@@ -257,7 +257,7 @@ void Status::Changes::playlist()
 			auto it = myPlaylist->main().begin()+playlist_length;
 			auto end = myPlaylist->main().end();
 			for (; it != end; ++it)
-				myPlaylist->unregisterHash(it->value().getHash());
+				myPlaylist->unregisterSong(it->value());
 			myPlaylist->main().resizeList(playlist_length);
 		}
 		
@@ -267,12 +267,12 @@ void Status::Changes::playlist()
 			{
 				// if song's already in playlist, replace it with a new one
 				MPD::Song &old_s = myPlaylist->main()[pos].value();
-				myPlaylist->unregisterHash(old_s.getHash());
+				myPlaylist->unregisterSong(old_s);
 				old_s = s;
 			}
 			else // otherwise just add it to playlist
 				myPlaylist->main().addItem(s);
-			myPlaylist->registerHash(s.getHash());
+			myPlaylist->registerSong(s);
 		});
 	});
 	

src/tag_editor.cpp

@@ -1025,7 +1025,7 @@ void TagEditor::LocateSong(const MPD::Song &s)
 	// highlight our file
 	for (size_t i = 0; i < Tags->size(); ++i)
 	{
-		if ((*Tags)[i].value().getHash() == s.getHash())
+		if ((*Tags)[i].value() == s)
 		{
 			Tags->highlight(i);
 			break;