i2psnark: Better handling of read-only i2psnark dir (ticket #1990)

Prevent add/create/remove/delete
More handling of RuntimeException via Snark.fatal() in SnarkManager

apps/i2psnark/java/src/org/klomp/snark/Snark.java

@@ -1243,8 +1243,13 @@ public class Snark
       } catch (IOException ioe) {
           if (storage != null) {
               try { storage.close(); } catch (IOException ioee) {}
+              // clear storage, we have a mess if we have non-null storage and null metainfo,
+              // as on restart, Storage.reopen() will throw an ioe
+              storage = null;
           }
-          fatal("Could not check or create storage", ioe);
+          // TODO we're still in an inconsistent state, won't work if restarted
+          // (PeerState "disconnecting seed that connects to seeds"
+          fatal("Could not create data files", ioe);
       }
   }
 

apps/i2psnark/java/src/org/klomp/snark/SnarkManager.java

@@ -731,7 +731,7 @@ public class SnarkManager implements CompleteListener, ClientApp {
         return new SHA1Hash(ih);
     }
 
-    /** null to set initial defaults */
+    /** @param filename null to set initial defaults */
     public void loadConfig(String filename) {
         synchronized(_configLock) {
             locked_loadConfig(filename);
@@ -896,7 +896,14 @@ public class SnarkManager implements CompleteListener, ClientApp {
         _util.setRatingsEnabled(Boolean.parseBoolean(_config.getProperty(PROP_RATINGS, "true")));
         _util.setCommentsEnabled(Boolean.parseBoolean(_config.getProperty(PROP_COMMENTS, "true")));
         _util.setCommentsName(_config.getProperty(PROP_COMMENTS_NAME, ""));
-        getDataDir().mkdirs();
+        File dd = getDataDir();
+        if (dd.isDirectory()) {
+            if (!dd.canWrite())
+                addMessage(_t("No write permissions for data directory") + ": " + dd);
+        } else {
+            if (!dd.mkdirs())
+                addMessage(_t("Data directory cannot be created") + ": " + dd);
+        }
         initTrackerMap();
     }
     
@@ -1031,6 +1038,8 @@ public class SnarkManager implements CompleteListener, ClientApp {
             } else if (!dd.canRead()) {
                 addMessage(_t("Unreadable") + ": " + dataDir);
             } else {
+                if (!dd.canWrite())
+                    addMessage(_t("No write permissions for data directory") + ": " + dataDir);
                 changed = true;
                 interruptMonitor = true;
                 _config.setProperty(PROP_DIR, dataDir);
@@ -2640,6 +2649,7 @@ public class SnarkManager implements CompleteListener, ClientApp {
 
     /**
      *  If not connected, thread it, otherwise inline
+     *  @throws RuntimeException via Snark.fatal()
      *  @since 0.9.1
      */
     public void startTorrent(byte[] infoHash) {
@@ -2654,6 +2664,7 @@ public class SnarkManager implements CompleteListener, ClientApp {
 
     /**
      *  If not connected, thread it, otherwise inline
+     *  @throws RuntimeException via Snark.fatal()
      *  @since 0.9.23
      */
     public void startTorrent(Snark snark) {
@@ -2701,17 +2712,14 @@ public class SnarkManager implements CompleteListener, ClientApp {
         private final Snark snark;
         public ThreadedStarter(Snark s) { snark = s; }
         public void run() {
-            try {
-                run2();
-            } catch (RuntimeException e) {
-                _log.error("Error starting", e);
-            }
-        }
-
-        private void run2() {
             if (snark != null) {
-                if (snark.isStopped())
+                if (snark.isStopped()) {
-                    snark.startTorrent();
+                    try {
+                        snark.startTorrent();
+                    } catch (RuntimeException re) {
+                        // Snark.fatal() will log and call fatal() here for user message before throwing
+                    }
+                }
             } else {
                 startAll();
             }
@@ -2724,8 +2732,13 @@ public class SnarkManager implements CompleteListener, ClientApp {
      */
     private void startAll() {
         for (Snark snark : _snarks.values()) {
-            if (snark.isStopped())
+            if (snark.isStopped()) {
-                snark.startTorrent();
+                try {
+                    snark.startTorrent();
+                } catch (RuntimeException re) {
+                    // Snark.fatal() will log and call fatal() here for user message before throwing
+                }
+            }
         }
     }
 

apps/i2psnark/java/src/org/klomp/snark/web/I2PSnarkServlet.java

@@ -987,6 +987,11 @@ public class I2PSnarkServlet extends BasicServlet {
                         }
                     }
                 }
+                File dd = _manager.getDataDir();
+                if (!dd.canWrite()) {
+                    _manager.addMessage(_t("No write permissions for data directory") + ": " + dd);
+                    return;
+                }
                 if (newURL.startsWith("http://")) {
                     FetchAndAdd fetch = new FetchAndAdd(_context, _manager, newURL, dir);
                     _manager.addDownloader(fetch);
@@ -1045,12 +1050,18 @@ public class I2PSnarkServlet extends BasicServlet {
                                 _manager.addMessage(_t("Magnet deleted: {0}", name));
                                 return;
                             }
-                            _manager.stopTorrent(snark, true);
-                            // should we delete the torrent file?
-                            // yeah, need to, otherwise it'll get autoadded again (at the moment
                             File f = new File(name);
-                            f.delete();
+                            File dd = _manager.getDataDir();
-                            _manager.addMessage(_t("Torrent file deleted: {0}", f.getAbsolutePath()));
+                            boolean canDelete = dd.canWrite() || !f.exists();
+                            _manager.stopTorrent(snark, canDelete);
+                            // TODO race here with the DirMonitor, could get re-added
+                            if (f.delete()) {
+                                _manager.addMessage(_t("Torrent file deleted: {0}", f.getAbsolutePath()));
+                            } else if (f.exists()) {
+                                if (!canDelete)
+                                    _manager.addMessage(_t("No write permissions for data directory") + ": " + dd);
+                                _manager.addMessage(_t("Torrent file could not be deleted: {0}", f.getAbsolutePath()));
+                            }
                             break;
                         }
                     }
@@ -1074,10 +1085,19 @@ public class I2PSnarkServlet extends BasicServlet {
                                     _manager.addMessage(_t("Magnet deleted: {0}", name));
                                 return;
                             }
-                            _manager.stopTorrent(snark, true);
                             File f = new File(name);
-                            f.delete();
+                            File dd = _manager.getDataDir();
-                            _manager.addMessage(_t("Torrent file deleted: {0}", f.getAbsolutePath()));
+                            boolean canDelete = dd.canWrite() || !f.exists();
+                            _manager.stopTorrent(snark, canDelete);
+                            // TODO race here with the DirMonitor, could get re-added
+                            if (f.delete()) {
+                                _manager.addMessage(_t("Torrent file deleted: {0}", f.getAbsolutePath()));
+                            } else if (f.exists()) {
+                                if (!canDelete)
+                                    _manager.addMessage(_t("No write permissions for data directory") + ": " + dd);
+                                _manager.addMessage(_t("Torrent file could not be deleted: {0}", f.getAbsolutePath()));
+                                return;
+                            }
                             Storage storage = snark.getStorage();
                             if (storage == null)
                                 break;
@@ -1178,6 +1198,11 @@ public class I2PSnarkServlet extends BasicServlet {
                 //    announceURL = announceURLOther;
 
                 if (baseFile.exists()) {
+                    File dd = _manager.getDataDir();
+                    if (!dd.canWrite()) {
+                        _manager.addMessage(_t("No write permissions for data directory") + ": " + dd);
+                        return;
+                    }
                     String torrentName = baseFile.getName();
                     if (torrentName.toLowerCase(Locale.US).endsWith(".torrent")) {
                         _manager.addMessage(_t("Cannot add a torrent ending in \".torrent\": {0}", baseFile.getAbsolutePath()));