Raise error if FileNotFoundException is caught for an existing file

File, FileInputStream and friends may throw FileNotFoundException even
if the file is existing e.g. when file permissions don't allow to access
the file content. In most cases this is a severe error we should not
suppress hence rethrow the FileNotFoundException in this case.

This may also fix bug 451508.

Bug: 451508
Change-Id: If4a94217fb5b7cfd4c04d881902f3e86193c7008
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties

@@ -451,6 +451,7 @@ packfileIsTruncated=Packfile {0} is truncated.
 packfileIsTruncatedNoParam=Packfile is truncated.
 packHandleIsStale=Pack file {0} handle is stale, removing it from pack list
 packHasUnresolvedDeltas=pack has unresolved deltas
+packInaccessible=Pack file {0} now inaccessible; removing it from pack list
 packingCancelledDuringObjectsWriting=Packing cancelled during objects writing
 packObjectCountMismatch=Pack object count mismatch: pack {0} index {1}: {2}
 packRefs=Pack refs

org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java

@@ -980,6 +980,9 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 		try {
 			raw = IO.readFully(authorScriptFile);
 		} catch (FileNotFoundException notFound) {
+			if (authorScriptFile.exists()) {
+				throw notFound;
+			}
 			return null;
 		}
 		return parseAuthor(raw);

org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java

@@ -510,6 +510,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String packfileIsTruncatedNoParam;
 	/***/ public String packHandleIsStale;
 	/***/ public String packHasUnresolvedDeltas;
+	/***/ public String packInaccessible;
 	/***/ public String packingCancelledDuringObjectsWriting;
 	/***/ public String packObjectCountMismatch;
 	/***/ public String packRefs;

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/LockFile.java

@@ -227,6 +227,10 @@ public class LockFile {
 				fis.close();
 			}
 		} catch (FileNotFoundException fnfe) {
+			if (ref.exists()) {
+				unlock();
+				throw fnfe;
+			}
 			// Don't worry about a file that doesn't exist yet, it
 			// conceptually has no current content to copy.
 			//

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java

@@ -433,16 +433,14 @@ public class ObjectDirectory extends FileObjectDatabase {
 
 	ObjectLoader openLooseObject(WindowCursor curs, AnyObjectId id)
 			throws IOException {
-		try {
-			File path = fileFor(id);
-			FileInputStream in = new FileInputStream(path);
-			try {
-				unpackedObjectCache.add(id);
-				return UnpackedObject.open(in, path, id, curs);
-			} finally {
-				in.close();
-			}
+		File path = fileFor(id);
+		try (FileInputStream in = new FileInputStream(path)) {
+			unpackedObjectCache.add(id);
+			return UnpackedObject.open(in, path, id, curs);
 		} catch (FileNotFoundException noFile) {
+			if (path.exists()) {
+				throw noFile;
+			}
 			unpackedObjectCache.remove(id);
 			return null;
 		}
@@ -513,15 +511,14 @@ public class ObjectDirectory extends FileObjectDatabase {
 
 	private long getLooseObjectSize(WindowCursor curs, AnyObjectId id)
 			throws IOException {
-		try {
-			FileInputStream in = new FileInputStream(fileFor(id));
-			try {
-				unpackedObjectCache.add(id);
-				return UnpackedObject.getSize(in, id, curs);
-			} finally {
-				in.close();
-			}
+		File f = fileFor(id);
+		try (FileInputStream in = new FileInputStream(f)) {
+			unpackedObjectCache.add(id);
+			return UnpackedObject.getSize(in, id, curs);
 		} catch (FileNotFoundException noFile) {
+			if (f.exists()) {
+				throw noFile;
+			}
 			unpackedObjectCache.remove(id);
 			return -1;
 		}
@@ -561,7 +558,11 @@ public class ObjectDirectory extends FileObjectDatabase {
 			// Assume the pack is corrupted, and remove it from the list.
 			removePack(p);
 		} else if (e instanceof FileNotFoundException) {
-			warnTmpl = JGitText.get().packWasDeleted;
+			if (p.getPackFile().exists()) {
+				warnTmpl = JGitText.get().packInaccessible;
+			} else {
+				warnTmpl = JGitText.get().packWasDeleted;
+			}
 			removePack(p);
 		} else if (FileUtils.isStaleFileHandle(e)) {
 			warnTmpl = JGitText.get().packHandleIsStale;

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java

@@ -788,6 +788,9 @@ public class RefDirectory extends RefDatabase {
 						new DigestInputStream(new FileInputStream(packedRefsFile),
 								digest), CHARSET));
 			} catch (FileNotFoundException noPackedRefs) {
+				if (packedRefsFile.exists()) {
+					throw noPackedRefs;
+				}
 				// Ignore it and leave the new list empty.
 				return PackedRefList.NO_PACKED_REFS;
 			}
@@ -944,7 +947,10 @@ public class RefDirectory extends RefDatabase {
 		try {
 			buf = IO.readSome(path, limit);
 		} catch (FileNotFoundException noFile) {
-			return null; // doesn't exist; not a reference.
+			if (path.exists() && path.isFile()) {
+				throw noFile;
+			}
+			return null; // doesn't exist or no file; not a reference.
 		}
 
 		int n = buf.length;

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ReflogReaderImpl.java

@@ -96,6 +96,9 @@ class ReflogReaderImpl implements ReflogReader {
 		try {
 			log = IO.readFully(logName);
 		} catch (FileNotFoundException e) {
+			if (logName.exists()) {
+				throw e;
+			}
 			return null;
 		}
 
@@ -118,6 +121,9 @@ class ReflogReaderImpl implements ReflogReader {
 		try {
 			log = IO.readFully(logName);
 		} catch (FileNotFoundException e) {
+			if (logName.exists()) {
+				throw e;
+			}
 			return Collections.emptyList();
 		}
 

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/UnpackedObject.java

@@ -399,6 +399,9 @@ public class UnpackedObject {
 			try {
 				in = buffer(new FileInputStream(path));
 			} catch (FileNotFoundException gone) {
+				if (path.exists()) {
+					throw gone;
+				}
 				// If the loose file no longer exists, it may have been
 				// moved into a pack file in the mean time. Try again
 				// to locate the object.

org.eclipse.jgit/src/org/eclipse/jgit/lib/Repository.java

@@ -1590,6 +1590,9 @@ public abstract class Repository implements AutoCloseable {
 		try {
 			return RawParseUtils.decode(IO.readFully(mergeMsgFile));
 		} catch (FileNotFoundException e) {
+			if (mergeMsgFile.exists()) {
+				throw e;
+			}
 			// the file has disappeared in the meantime ignore it
 			return null;
 		}
@@ -1621,6 +1624,9 @@ public abstract class Repository implements AutoCloseable {
 			byte[] raw = IO.readFully(file);
 			return raw.length > 0 ? raw : null;
 		} catch (FileNotFoundException notFound) {
+			if (file.exists()) {
+				throw notFound;
+			}
 			return null;
 		}
 	}

org.eclipse.jgit/src/org/eclipse/jgit/storage/file/FileBasedConfig.java

@@ -163,6 +163,9 @@ public class FileBasedConfig extends StoredConfig {
 				hash = newHash;
 			}
 		} catch (FileNotFoundException noFile) {
+			if (configFile.exists()) {
+				throw noFile;
+			}
 			clear();
 			snapshot = newSnapshot;
 		} catch (IOException e) {