libsaria: Resizing a vector invalidates pointers

I was keeping a vector of objects, and then pass pointers to these
objects around everywhere.  HOWEVER, when vectors are resized they
allocate new memory and copy things over invalidating iterators and
pointers to the original objects.  This can cause memory corruption
issues when I try to use a pointer to an object that no longer exists.

The simple solution?  Allocate tracks dynamically and then store the
pointer in the library path.

Signed-off-by: Bryan Schumaker <bjschuma@gmail.com>

include/library.h

@@ -19,10 +19,11 @@ namespace libsaria
 			bool visible;
 			unsigned int id;
 			string path;
-			vector<Track> tracks;
+			vector<Track *> tracks;
 		};
 
 		void init();
+		void quit();
 		void add_path(string);
 		void delete_path(Path *);
 		void update_path(Path *);

libsaria/idle/idle.cpp

@@ -66,7 +66,7 @@ static void do_task(IdleTask *task)
 
 static void queue_task(IdleTask *task)
 {
-	idle_queue.push_front(task);
+	idle_queue.push_back(task);
 	queued += 1.0;
 	libsaria::notify(IDLE_ADD, NULL);
 }

libsaria/library/file.cpp

@@ -28,7 +28,6 @@ static string id_to_filename(unsigned int id)
 static void do_save_path(ofstream &stream, void *data)
 {
 	libsaria::library::Path *path = (libsaria::library::Path *)data;
-	list<libsaria::Track>::iterator it;
 	println("Saving library path: %d", path->id);
 
 	stream << LIBRARY_CURRENT_VERSION << "\n";
@@ -37,7 +36,7 @@ static void do_save_path(ofstream &stream, void *data)
 	stream << path->tracks.size() << "\n";
 
 	for (unsigned int i = 0; i < path->tracks.size(); i++)
-		path->tracks[i].save(&stream);
+		path->tracks[i]->save(&stream);
 }
 
 void libsaria::library::save_path(libsaria::library::Path *path)
@@ -76,8 +75,8 @@ void read_path(ifstream &stream)
 
 	path_ptr = push_path(path);
 	for (unsigned int i = 0; i < size; i++) {
-		path_ptr->tracks.push_back(libsaria::Track(stream, path_ptr, version));
-		track = &path_ptr->tracks.back();
+		track = new libsaria::Track(stream, path_ptr, version);
+		path_ptr->tracks.push_back(track);
 		if ((*track)[TRACK_ID] != i)
 			(*track)[TRACK_ID] = i;
 	}

libsaria/library/library.cpp

@@ -29,12 +29,12 @@ libsaria::library::Path *push_path(libsaria::library::Path &path)
 	return ptr;
 }
 
-static void hide_track(libsaria::Track &track)
+static void hide_track(libsaria::Track *track)
 {
-	if (track[TRACK_BANNED])
-		libsaria::ban::get_banned_plist()->remove_track(&track);
+	if ((*track)[TRACK_BANNED])
+		libsaria::ban::get_banned_plist()->remove_track(track);
 	else
-		lib_playlist.remove_track(&track);
+		lib_playlist.remove_track(track);
 }
 
 void pop_path(libsaria::library::Path *path)
@@ -74,13 +74,10 @@ namespace libsaria
 
 	void library::delete_path(Path *path)
 	{
-		list<Track>::iterator it;
-		list<Path>::iterator p_it;
-
 		remove_file(path);
 		for (unsigned int i = 0; i < path->tracks.size(); i++) {
 			hide_track(path->tracks[i]);
-			libsaria::deck::track_removed(&path->tracks[i]);
+			libsaria::deck::track_removed(path->tracks[i]);
 		}
 		pop_path(path);
 	}
@@ -101,7 +98,7 @@ namespace libsaria
 	{
 		for (unsigned int i = 0; i < path->tracks.size(); i++) {
 			hide_track(path->tracks[i]);
-			libsaria::deck::track_removed(&path->tracks[i]);
+			libsaria::deck::track_removed(path->tracks[i]);
 		}
 		path->visible = false;
 		save_path(path);
@@ -114,7 +111,7 @@ namespace libsaria
 		Track *track;
 
 		for (unsigned int i = 0; i < path->tracks.size(); i++) {
-			track = &path->tracks[i];
+			track = path->tracks[i];
 			if ((*track)[TRACK_BANNED])
 				ban.push_back(track);
 			else
@@ -134,7 +131,7 @@ namespace libsaria
 			return NULL;
 		if (trackid >= path_list[libid].tracks.size())
 			return NULL;
-		return &path_list[libid].tracks[trackid];
+		return path_list[libid].tracks[trackid];
 	}
 
 	void library::set_random(bool random)
@@ -158,4 +155,14 @@ namespace libsaria
 		idle::schedule(restore_current);
 	}
 
+	void library::quit()
+	{
+		struct libsaria::library::Path *path;
+		for (unsigned int i = 0; i < path_list.size(); i++) {
+			path = &path_list[i];
+			for (unsigned int j = 0; j < path->tracks.size(); j++)
+				delete path->tracks[j];
+		}
+	}
+
 }; /* namespace: libsaria */

libsaria/library/update.cpp

@@ -18,7 +18,7 @@ static void validate_path(void *d)
 
 	path = (struct libsaria::library::Path *)d;
 	while (i < path->tracks.size()) {
-		track = &path->tracks[i];
+		track = path->tracks[i];
 		if (!libsaria::exists((*track)[TRACK_FILEPATH])) {
 			println("Reaping: " + (*track)[TRACK_FILEPATH]);
 			lib_playlist.remove_track(track);
@@ -54,7 +54,7 @@ static void setup_scan_data(struct ScanData *scan, list<string> &files)
 static bool find_file(libsaria::library::Path *path, string &file)
 {
 	for (unsigned int i = 0; i < path->tracks.size(); i++) {
-		if (path->tracks[i][TRACK_FILEPATH] == file)
+		if ((*path->tracks[i])[TRACK_FILEPATH] == file)
 			return true;
 	}
 	return false;
@@ -65,6 +65,7 @@ static void scan_path(void *data)
 	struct ScanData *scan = (struct ScanData *)data;
 	list<string>::iterator it;
 	libsaria::library::Path *path = scan->path;
+	libsaria::Track *track;
 
 	for (it = scan->files.begin(); it != scan->files.end(); it++) {
 		/*
@@ -77,8 +78,9 @@ static void scan_path(void *data)
 			continue;
 
 		try {
-			path->tracks.push_back(libsaria::Track(*it, path));
-			lib_playlist.push_back(&path->tracks.back());
+			track = new libsaria::Track(*it, path);
+			path->tracks.push_back(track);
+			lib_playlist.push_back(track);
 		} catch (string message) {
 			println(message);
 		}
@@ -88,12 +90,10 @@ static void scan_path(void *data)
 	delete scan;
 }
 
-
 static void update_path(void *d)
 {
 	struct libsaria::library::Path *path;
 	list<string> file_list;
-	list<string>::iterator it;
 	unsigned int i;
 	struct ScanData *data;
 

libsaria/libsaria.cpp

@@ -39,6 +39,7 @@ namespace libsaria
 	{
 		println("Quitting libsaria");
 		app::close_pipe();
+		library::quit();
 		audio::quit();
 		print_format_stats();
 	}