Copy picture struct for worker thread

This copies the picture struct when delegating image handling
to a worker thread to prevent a crashe when main thread
frees the picture upon selecting a different dive.

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

dive.c

@@ -2357,6 +2357,20 @@ static void free_pic(struct picture *picture)
 	}
 }
 
+// When handling pictures in different threads, we need to copy them so we don't
+// run into problems when the main thread frees the picture.
+
+struct picture *clone_picture(struct picture *src)
+{
+	struct picture *dst;
+
+	dst = alloc_picture();
+	copy_pl(src, dst);
+	return dst;
+}
+
+
+
 static int same_sample(struct sample *a, struct sample *b)
 {
 	if (a->time.seconds != b->time.seconds)
@@ -3387,7 +3401,7 @@ void dive_set_geodata_from_picture(struct dive *dive, struct picture *picture)
 	}
 }
 
-static void picture_free(struct picture *picture)
+void picture_free(struct picture *picture)
 {
 	if (!picture)
 		return;

dive.h

@@ -376,6 +376,7 @@ struct picture {
 	for (struct picture *picture = (_divestruct).picture_list; picture; picture = picture->next)
 
 extern struct picture *alloc_picture();
+extern struct picture *clone_picture(struct picture *src);
 extern bool dive_check_picture_time(struct dive *d, int shift_time, timestamp_t timestamp);
 extern void dive_create_picture(struct dive *d, char *filename, int shift_time, bool match_all);
 extern void dive_add_picture(struct dive *d, struct picture *newpic);
@@ -385,6 +386,7 @@ extern bool picture_check_valid(char *filename, int shift_time);
 extern void picture_load_exif_data(struct picture *p);
 extern timestamp_t picture_get_timestamp(char *filename);
 extern void dive_set_geodata_from_picture(struct dive *d, struct picture *pic);
+extern void picture_free(struct picture *picture);
 
 extern int explicit_first_cylinder(struct dive *dive, struct divecomputer *dc);
 extern int get_depth_at_time(struct divecomputer *dc, int time);

qt-ui/divepicturewidget.cpp

@@ -23,16 +23,17 @@ void loadPicture(struct picture *picture)
 
 SHashedImage::SHashedImage(struct picture *picture) : QImage()
 {
-	QUrl url = QUrl::fromUserInput(QString(picture->filename));
+	QUrl url = QUrl::fromUserInput(localFilePath(QString(picture->filename)));
+
 	if(url.isLocalFile())
 		load(url.toLocalFile());
 	if (isNull()) {
 		// Hash lookup.
 		load(fileFromHash(picture->hash));
 		if (!isNull()) {
-			QtConcurrent::run(updateHash, picture);
+			QtConcurrent::run(updateHash, clone_picture(picture));
 		} else {
-			QtConcurrent::run(loadPicture, picture);
+			QtConcurrent::run(loadPicture, clone_picture(picture));
 		}
 	} else {
 		QByteArray hash = hashFile(url.toLocalFile());
@@ -46,6 +47,11 @@ ImageDownloader::ImageDownloader(struct picture *pic)
 	picture = pic;
 }
 
+ImageDownloader::~ImageDownloader()
+{
+	picture_free(picture);
+}
+
 void ImageDownloader::load(){
 	QUrl url = QUrl::fromUserInput(QString(picture->filename));
 	if (url.isValid()) {
@@ -64,6 +70,7 @@ void ImageDownloader::load(){
 void ImageDownloader::saveImage(QNetworkReply *reply)
 {
 	QByteArray imageData = reply->readAll();
+	qDebug() << "downloaded ";
 	QImage image = QImage();
 	image.loadFromData(imageData);
 	if (image.isNull())

qt-ui/divepicturewidget.h

@@ -11,6 +11,7 @@ class ImageDownloader : public QObject {
 	Q_OBJECT;
 public:
 	ImageDownloader(struct picture *picture);
+	~ImageDownloader();
 	void load();
 private:
 	struct picture *picture;

qthelper.cpp

@@ -1182,9 +1182,11 @@ void learnHash(struct picture *picture, QByteArray hash)
 
 QString localFilePath(const QString originalFilename)
 {
-	if (hashOf.contains(originalFilename) && localFilenameOf.contains(hashOf[originalFilename]))
+	if (hashOf.contains(originalFilename))
+		if (localFilenameOf.contains(hashOf[originalFilename]))
+			if (localFilenameOf[hashOf[originalFilename]] != "")
 				return localFilenameOf[hashOf[originalFilename]];
-	else
+
 		return originalFilename;
 }
 
@@ -1200,6 +1202,7 @@ void updateHash(struct picture *picture) {
 	char *old = picture->hash;
 	picture->hash = strdup(hash.toHex());
 	free(old);
+	picture_free(picture);
 }
 
 void hashPicture(struct picture *picture)
@@ -1209,13 +1212,14 @@ void hashPicture(struct picture *picture)
 	if (!same_string(picture->hash, "") && !same_string(picture->hash, oldHash))
 		mark_divelist_changed((true));
 	free(oldHash);
+	picture_free(picture);
 }
 
 extern "C" void cache_picture(struct picture *picture)
 {
 	QString filename = picture->filename;
 	if (!hashOf.contains(filename))
-		QtConcurrent::run(hashPicture, picture);
+		QtConcurrent::run(hashPicture, clone_picture(picture));
 }
 
 void learnImages(const QDir dir, int max_recursions, bool recursed)