Dive pictures: remove hashes

In the last commits, the canonical-to-local filename map was made
independent from the image hashes and the location of moved images
was based on filename not hashes. The hashes are now in principle
unused (except for conversion of old-style local filename lookups).

Therefore, remove the hashes in this commit. This makes addition
of images distinctly faster.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 17 insertions, 77 deletions

diff --git a/core/qthelper.cpp b/core/qthelper.cpp
index 1d77dbad6..c58811c14 100644
--- a/core/qthelper.cpp
+++ b/core/qthelper.cpp
@@ -1042,27 +1042,10 @@ extern "C" void reverseGeoLookup(degrees_t latitude, degrees_t longitude, uint32
 	}
 }
 
-QHash<QString, QByteArray> hashOf;
-QMutex hashOfMutex;
-QHash<QString, QString> localFilenameOf;
+static QMutex hashOfMutex;
+static QHash<QString, QString> localFilenameOf;
 
-static QByteArray getHash(const QString &filename)
-{
-	QMutexLocker locker(&hashOfMutex);
-	return hashOf[filename];
-}
-
-QString hashString(const char *filename)
-{
-	return getHash(QString(filename)).toHex();
-}
-
-extern "C" char * hashstring(const char *filename)
-{
-	return strdup(qPrintable(hashString(filename)));
-}
-
-const QString hashfile_name()
+static const QString hashfile_name()
 {
 	return QString(system_default_directory()).append("/hashes");
 }
@@ -1137,7 +1120,7 @@ struct HashToFile {
 
 // During a transition period, convert the hash->localFilename into a canonicalFilename->localFilename.
 // TODO: remove this code in due course
-static void convertLocalFilename(const QHash<QByteArray, QString> &hashToLocal)
+static void convertLocalFilename(const QHash<QString, QByteArray> &hashOf, const QHash<QByteArray, QString> &hashToLocal)
 {
 	// Bail out early if there is nothing to do
 	if (hashToLocal.isEmpty())
@@ -1172,25 +1155,20 @@ void read_hashes()
 	if (hashfile.open(QIODevice::ReadOnly)) {
 		QDataStream stream(&hashfile);
 		QHash<QByteArray, QString> localFilenameByHash;
+		QHash<QString, QByteArray> hashOf;
 		stream >> localFilenameByHash;		// For backwards compatibility
-		QMutexLocker locker(&hashOfMutex);
-		stream >> hashOf;
-		locker.unlock();
+		stream >> hashOf;			// For backwards compatibility
 		QHash <QString, QImage> thumbnailCache;
 		stream >> thumbnailCache;		// For backwards compatibility
+		QMutexLocker locker(&hashOfMutex);
 		stream >> localFilenameOf;
+		locker.unlock();
 		hashfile.close();
 		convertThumbnails(thumbnailCache);
-		convertLocalFilename(localFilenameByHash);
+		convertLocalFilename(hashOf, localFilenameByHash);
 	}
 	QMutexLocker locker(&hashOfMutex);
 	localFilenameOf.remove("");
-	QMutableHashIterator<QString, QByteArray> iter(hashOf);
-	while (iter.hasNext()) {
-		iter.next();
-		if (iter.value().isEmpty())
-			iter.remove();
-	}
 
 	// Make sure that the thumbnail directory exists
 	QDir().mkpath(thumbnailDir());
@@ -1204,7 +1182,7 @@ void write_hashes()
 	if (hashfile.open(QIODevice::WriteOnly)) {
 		QDataStream stream(&hashfile);
 		stream << QHash<QByteArray, QString>();	// Empty hash to filename - for backwards compatibility
-		stream << hashOf;
+		stream << QHash<QString, QByteArray>(); // Empty hashes - for backwards compatibility
 		stream << QHash<QString,QImage>();	// Empty thumbnailCache - for backwards compatibility
 		stream << localFilenameOf;
 		hashfile.commit();
@@ -1213,32 +1191,6 @@ void write_hashes()
 	}
 }
 
-// Add hash if not already known
-extern "C" void register_hash(const char *filename, const char *hash)
-{
-	if (empty_string(filename) || empty_string(hash))
-		return;
-	QString filenameString(filename);
-
-	QMutexLocker locker(&hashOfMutex);
-	if (!hashOf.contains(filenameString)) {
-		QByteArray hashBuf = QByteArray::fromHex(hash);
-		hashOf[filename] =  hashBuf;
-	}
-}
-
-QByteArray hashFile(const QString &filename)
-{
-	QCryptographicHash hash(QCryptographicHash::Sha1);
-	QFile imagefile(filename);
-	if (imagefile.exists() && imagefile.open(QIODevice::ReadOnly)) {
-		hash.addData(&imagefile);
-		return hash.result();
-	} else {
-		return QByteArray();
-	}
-}
-
 void learnPictureFilename(const QString &originalName, const QString &localName)
 {
 	if (originalName.isEmpty() || localName.isEmpty())
@@ -1257,18 +1209,6 @@ QString localFilePath(const QString &originalFilename)
 	return localFilenameOf.value(originalFilename, originalFilename);
 }
 
-// This works on a copy of the string, because it runs in asynchronous context
-void hashPicture(QString filename)
-{
-	QByteArray oldHash = getHash(filename);
-	QByteArray hash = hashFile(localFilePath(filename));
-	if (!hash.isEmpty() && hash != oldHash) {
-		QMutexLocker locker(&hashOfMutex);
-		hashOf[filename] =  hash;
-		mark_divelist_changed(true);
-	}
-}
-
 QStringList imageExtensionFilters() {
 	QStringList filters;
 	foreach (QString format, QImageReader::supportedImageFormats()) {
@@ -1312,19 +1252,19 @@ struct ImageMatch {
 	int score;
 };
 
-static void learnImage(const QString &filename, QMap<QString, ImageMatch> &matches)
+static void learnImage(const QString &filename, QMap<QString, ImageMatch> &matches, const QVector<QString> &imageFilenames)
 {
 	// Find the original filenames with the highest match-score
 	QStringList newMatches;
-	QByteArray hash = hashFile(filename);
 	int bestScore = 1;
-	for (auto it = hashOf.cbegin(); it != hashOf.cend(); ++it) {
-		int score = matchFilename(filename, it.key());
+
+	for (const QString &originalFilename: imageFilenames) {
+		int score = matchFilename(filename, originalFilename);
 		if (score < bestScore)
 			continue;
 		if (score > bestScore)
 			newMatches.clear();
-		newMatches.append(it.key());
+		newMatches.append(originalFilename);
 		bestScore = score;
 	}
 
@@ -1338,7 +1278,7 @@ static void learnImage(const QString &filename, QMap<QString, ImageMatch> &match
 	}
 }
 
-void learnImages(const QStringList &dirNames, int max_recursions)
+void learnImages(const QStringList &dirNames, int max_recursions, const QVector<QString> &imageFilenames)
 {
 	QStringList filters = imageExtensionFilters();
 	QMap<QString, ImageMatch> matches;
@@ -1354,7 +1294,7 @@ void learnImages(const QStringList &dirNames, int max_recursions)
 		QDir dir(stack.last().takeLast());
 
 		for (const QString &file: dir.entryList(filters, QDir::Files))
-			learnImage(dir.absoluteFilePath(file), matches);
+			learnImage(dir.absoluteFilePath(file), matches, imageFilenames);
 		if (stack.size() <= max_recursions) {
 			stack.append(QStringList());
 			for (const QString &dirname: dir.entryList(QStringList(), QDir::NoDotAndDotDot | QDir::Dirs))