ObjectDirectory: improve reading of shallow file

Use FileUtils.readWithRetries().

Change-Id: I5929184caca6b83a1ee87b462e541620bd68aa90

2 files changed, 30 insertions, 15 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
index 551a5a8a9d..964debcccb 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java
@@ -618,6 +618,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String pushOptionsNotSupported;
 	/***/ public String rawLogMessageDoesNotParseAsLogEntry;
 	/***/ public String readConfigFailed;
+	/***/ public String readShallowFailed;
 	/***/ public String readFileStoreAttributesFailed;
 	/***/ public String readerIsRequired;
 	/***/ public String readingObjectsFromLocalRepositoryFailed;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java
index 1a1d31a632..7699439128 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/ObjectDirectory.java
@@ -567,22 +567,36 @@ public class ObjectDirectory extends FileObjectDatabase {
 
 		if (shallowFileSnapshot == null
 				|| shallowFileSnapshot.isModified(shallowFile)) {
-			shallowCommitsIds = new HashSet<>();
-
-			try (BufferedReader reader = open(shallowFile)) {
-				String line;
-				while ((line = reader.readLine()) != null) {
-					try {
-						shallowCommitsIds.add(ObjectId.fromString(line));
-					} catch (IllegalArgumentException ex) {
-						throw new IOException(MessageFormat
-								.format(JGitText.get().badShallowLine, line),
-								ex);
-					}
-				}
+			try {
+				shallowCommitsIds = FileUtils.readWithRetries(shallowFile,
+						f -> {
+							FileSnapshot newSnapshot = FileSnapshot.save(f);
+							HashSet<ObjectId> result = new HashSet<>();
+							try (BufferedReader reader = open(f)) {
+								String line;
+								while ((line = reader.readLine()) != null) {
+									if (!ObjectId.isId(line)) {
+										throw new IOException(
+												MessageFormat.format(JGitText
+														.get().badShallowLine,
+														f.getAbsolutePath(),
+														line));
+
+									}
+									result.add(ObjectId.fromString(line));
+								}
+							}
+							shallowFileSnapshot = newSnapshot;
+							return result;
+						});
+			} catch (IOException e) {
+				throw e;
+			} catch (Exception e) {
+				throw new IOException(
+						MessageFormat.format(JGitText.get().readShallowFailed,
+								shallowFile.getAbsolutePath()),
+						e);
 			}
-
-			shallowFileSnapshot = FileSnapshot.save(shallowFile);
 		}
 
 		return shallowCommitsIds;