Improved support for read / writing CRC32 checksum to / from xattr (and enable by default)

source/net/filebot/format/MediaBindingBean.java

@@ -42,11 +42,8 @@ import java.util.stream.IntStream;
 import java.util.stream.Stream;
 
 import net.filebot.ApplicationFolder;
-import net.filebot.Cache;
-import net.filebot.CacheType;
 import net.filebot.Language;
 import net.filebot.MediaTypes;
-import net.filebot.MetaAttributeView;
 import net.filebot.Resource;
 import net.filebot.Settings;
 import net.filebot.hash.HashType;
@@ -56,6 +53,7 @@ import net.filebot.media.LocalDatasource.PhotoFile;
 import net.filebot.media.MetaAttributes;
 import net.filebot.media.NamingStandard;
 import net.filebot.media.VideoFormat;
+import net.filebot.media.XattrChecksum;
 import net.filebot.mediainfo.MediaInfo;
 import net.filebot.mediainfo.MediaInfo.StreamKind;
 import net.filebot.mediainfo.MediaInfoException;
@@ -511,20 +509,8 @@ public class MediaBindingBean {
 			return checksum;
 		}
 
-		// try CRC32 xattr (as stored by verify script)
-		try {
-			MetaAttributeView xattr = new MetaAttributeView(inferredMediaFile);
-			checksum = xattr.get("CRC32");
-			if (checksum != null) {
-				return checksum;
-			}
-		} catch (Exception e) {
-			// ignore if xattr metadata is not supported for the given file
-		}
-
-		// calculate checksum from file
-		Cache cache = Cache.getCache("crc32", CacheType.Ephemeral);
-		return (String) cache.computeIfAbsent(inferredMediaFile, it -> crc32(inferredMediaFile));
+		// compute and store to xattr
+		return XattrChecksum.CRC32.computeIfAbsent(inferredMediaFile);
 	}
 
 	@Define("fn")

source/net/filebot/media/XattrChecksum.java

@@ -0,0 +1,77 @@
+package net.filebot.media;
+
+import static net.filebot.Logging.*;
+import static net.filebot.Settings.*;
+import static net.filebot.hash.VerificationUtilities.*;
+
+import java.io.File;
+import java.util.concurrent.TimeUnit;
+
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+
+import net.filebot.MetaAttributeView;
+import net.filebot.hash.HashType;
+
+public enum XattrChecksum {
+
+	CRC32;
+
+	private final Cache<File, String> cache = CacheBuilder.newBuilder().expireAfterAccess(24, TimeUnit.HOURS).build();
+
+	public String computeIfAbsent(File file) throws Exception {
+		return cache.get(file, () -> {
+			if (!useExtendedFileAttributes()) {
+				return computeHash(file, getHashType());
+			}
+
+			// read xattr
+			MetaAttributeView xattr = new MetaAttributeView(file);
+
+			String value = xattr.get(getKey());
+			if (value != null) {
+				return value;
+			}
+
+			// compute checksum
+			value = computeHash(file, getHashType());
+
+			// store checksum (and make sure Last-Modified date is not changed)
+			long t = file.lastModified();
+			try {
+				xattr.put(getKey(), value); // may or may not change Last-Modified date
+			} catch (Exception e) {
+				debug.warning(cause("Failed to set xattr", e));
+			} finally {
+				file.setLastModified(t);
+			}
+
+			return value;
+		});
+	}
+
+	public void clear(File file) {
+		cache.invalidate(cache);
+
+		if (useExtendedFileAttributes()) {
+			try {
+				new MetaAttributeView(file).put(getKey(), null);
+			} catch (Exception e) {
+				debug.warning(cause("Failed to set xattr", e));
+			}
+		}
+	}
+
+	private String getKey() {
+		return name();
+	}
+
+	private HashType getHashType() {
+		switch (this) {
+		case CRC32:
+			return HashType.SFV;
+		}
+		return null;
+	}
+
+}