From 5e58f0a0ebfcf523fa1bd7cc74e3808140c75261 Mon Sep 17 00:00:00 2001
From: James Moger <james.moger@gitblit.com>
Date: Mon, 20 Feb 2012 12:33:57 -0500
Subject: [PATCH] Workaround 1 sec resolution of File.lastModified on Linux
 (issue-55)

Shockingly, File.lastModified() does not always support millisecond
resolution on all platforms even if the underlying filesystem supports
it.  Added a forceReload flag (in addition to last modified checks) to
ensure that user backends and configuration properties are properly
reloaded.
---
 src/com/gitblit/ConfigUserService.java |  8 +++++++-
 src/com/gitblit/FileSettings.java      | 15 ++++++++++++++-
 src/com/gitblit/FileUserService.java   |  3 ++-
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/src/com/gitblit/ConfigUserService.java b/src/com/gitblit/ConfigUserService.java
index 681efd53..8f47f7a0 100644
--- a/src/com/gitblit/ConfigUserService.java
+++ b/src/com/gitblit/ConfigUserService.java
@@ -82,6 +82,8 @@ public class ConfigUserService implements IUserService {
 	private final Map<String, TeamModel> teams = new ConcurrentHashMap<String, TeamModel>();
 
 	private volatile long lastModified;
+	
+	private volatile boolean forceReload;
 
 	public ConfigUserService(File realmFile) {
 		this.realmFile = realmFile;
@@ -711,6 +713,9 @@ public class ConfigUserService implements IUserService {
 		}
 
 		config.save();
+		// manually set the forceReload flag because not all JVMs support real
+		// millisecond resolution of lastModified. (issue-55)
+		forceReload = true;
 
 		// If the write is successful, delete the current file and rename
 		// the temporary copy to the original filename.
@@ -735,7 +740,8 @@ public class ConfigUserService implements IUserService {
 	 * Reads the realm file and rebuilds the in-memory lookup tables.
 	 */
 	protected synchronized void read() {
-		if (realmFile.exists() && (realmFile.lastModified() > lastModified)) {
+		if (realmFile.exists() && (forceReload || (realmFile.lastModified() != lastModified))) {
+			forceReload = false;
 			lastModified = realmFile.lastModified();
 			users.clear();
 			cookies.clear();
diff --git a/src/com/gitblit/FileSettings.java b/src/com/gitblit/FileSettings.java
index 8ac99f6d..666bda05 100644
--- a/src/com/gitblit/FileSettings.java
+++ b/src/com/gitblit/FileSettings.java
@@ -37,6 +37,8 @@ public class FileSettings extends IStoredSettings {
 	private final Properties properties = new Properties();
 
 	private volatile long lastModified;
+	
+	private volatile boolean forceReload;
 
 	public FileSettings(String file) {
 		super(FileSettings.class);
@@ -49,7 +51,7 @@ public class FileSettings extends IStoredSettings {
 	 */
 	@Override
 	protected synchronized Properties read() {
-		if (propertiesFile.exists() && (propertiesFile.lastModified() > lastModified)) {
+		if (propertiesFile.exists() && (forceReload || (propertiesFile.lastModified() > lastModified))) {
 			FileInputStream is = null;
 			try {
 				Properties props = new Properties();
@@ -60,6 +62,7 @@ public class FileSettings extends IStoredSettings {
 				properties.clear();
 				properties.putAll(props);
 				lastModified = propertiesFile.lastModified();
+				forceReload = false;
 			} catch (FileNotFoundException f) {
 				// IGNORE - won't happen because file.exists() check above
 			} catch (Throwable t) {
@@ -88,6 +91,9 @@ public class FileSettings extends IStoredSettings {
 			content = content.replaceAll(regex, setting.getKey() + " = " + setting.getValue());
 		}
 		FileUtils.writeContent(propertiesFile, content);
+		// manually set the forceReload flag because not all JVMs support real
+		// millisecond resolution of lastModified. (issue-55)		
+		forceReload = true;
 		return true;
 	}
 	
@@ -102,6 +108,13 @@ public class FileSettings extends IStoredSettings {
 		return lastModified;
 	}
 
+	/**
+	 * @return the state of the force reload flag
+	 */
+	protected boolean forceReload() {
+		return forceReload;
+	}
+
 	@Override
 	public String toString() {
 		return propertiesFile.getAbsolutePath();
diff --git a/src/com/gitblit/FileUserService.java b/src/com/gitblit/FileUserService.java
index dfc4da8a..7842c31d 100644
--- a/src/com/gitblit/FileUserService.java
+++ b/src/com/gitblit/FileUserService.java
@@ -624,8 +624,9 @@ public class FileUserService extends FileSettings implements IUserService {
 	@Override
 	protected synchronized Properties read() {
 		long lastRead = lastModified();
+		boolean reload = forceReload();
 		Properties allUsers = super.read();
-		if (lastRead != lastModified()) {
+		if (reload || (lastRead != lastModified())) {
 			// reload hash cache
 			cookies.clear();
 			teams.clear();
-- 
2.39.5