Fix UID FETCH deadlock.

Also, after grabbing a lock, enter a try/catch that will unlock
and re-throw the error.

exec/imapservice.js

@@ -1394,6 +1394,7 @@ function open_cfg(usr)
 		return false;
 	}
 	lock_cfg();
+	try {
 		// Check if it's the old INI format...
 		if (cfgfile.length > 0) {
 			var ch = cfgfile.read(1);
@@ -1406,6 +1407,11 @@ function open_cfg(usr)
 		else {
 			save_cfg(false);
 		}
+	}
+	catch (error) {
+		unlock_cfg();
+		throw error;
+	}
 	unlock_cfg();
 	return true;
 }
@@ -1686,9 +1692,15 @@ var authenticated_command_handlers = {
 
 			if(msg_area.sub[sub]!=undefined && msg_area.sub[sub].can_read) {
 				lock_cfg();
+				try {
 					read_cfg(sub, false);
 					saved_config[sub].subscribed = true;
 					save_cfg(false);
+				}
+				catch (error) {
+					unlock_cfg();
+					throw error;
+				}
 				unlock_cfg();
 				tagged(tag, "OK", "Subscribed...");
 			}
@@ -1704,9 +1716,15 @@ var authenticated_command_handlers = {
 
 			if(msg_area.sub[sub]!=undefined && msg_area.sub[sub].can_read) {
 				lock_cfg();
+				try {
 					read_cfg(sub, false);
 					saved_config[sub].subscribed = false;
 					save_cfg(false);
+				}
+				catch (error) {
+					unlock_cfg();
+					throw error;
+				}
 				unlock_cfg();
 				tagged(tag, "OK", "Unsubscribed...");
 			}
@@ -1841,6 +1859,7 @@ function do_store(seq, uid, item, data)
 	var changed=false;
 
 	lock_cfg();
+	try {
 		read_cfg(index.code, false);
 		for(i in seq) {
 			idx=index.idx[seq[i]];
@@ -1882,9 +1901,15 @@ function do_store(seq, uid, item, data)
 			js.gc();
 		}
 		save_cfg(false);
+	}
+	catch (error) {
+		unlock_cfg();
+		throw error;
+	}
 	unlock_cfg();
 	if(mod_seen && base.cfg != undefined) {
 		lock_cfg();
+		try {
 			read_cfg(base.cfg.code, false);
 			if(saved_config[base.cfg.code] == undefined) {
 				saved_config[base.cfg.code] = {subscribed:false};
@@ -1899,6 +1924,11 @@ function do_store(seq, uid, item, data)
 			else
 				index.idx[seq[i]].attr &= ~MSG_READ;
 			save_cfg(false);
+		}
+		catch (error) {
+			unlock_cfg();
+			throw error;
+		}
 		unlock_cfg();
 	}
 	if(changed)
@@ -2810,6 +2840,7 @@ var selected_command_handlers = {
 			var i;
 
 			lock_cfg();
+			try {
 				read_cfg(get_base_code(base), false);
 				for(i in seq) {
 					send_fetch_response(seq[i], data_items, false);
@@ -2817,6 +2848,11 @@ var selected_command_handlers = {
 						break;
 				}
 				save_cfg(false);
+			}
+			catch (error) {
+				unlock_cfg();
+				throw error;
+			}
 			unlock_cfg();
 			js.gc();
 			tagged(tag, "OK", "There they are!");
@@ -2865,6 +2901,7 @@ var selected_command_handlers = {
 					seq=parse_seq_set(args[2],true);
 					data_items=parse_data_items(args[3]);
 					lock_cfg();
+					try {
 						read_cfg(get_base_code(base), false);
 						for(i in seq) {
 							send_fetch_response(seq[i], data_items, true);
@@ -2872,7 +2909,12 @@ var selected_command_handlers = {
 								break;
 						}
 						save_cfg(false);
-					lock_cfg();
+					}
+					catch (error) {
+						unlock_cfg();
+						throw error;
+					}
+					unlock_cfg();
 					js.gc();
 					tagged(tag, "OK", "There they are (with UIDs)!");
 					break;
@@ -2986,6 +3028,7 @@ function read_cfg(sub, lck)
 
 	if (lck)
 		lock_cfg();
+	try {
 		if(saved_config[sub]==undefined)
 			saved_config[sub]={subscribed:false};
 
@@ -3028,6 +3071,12 @@ function read_cfg(sub, lck)
 				}
 			}
 		}
+	}
+	catch (error) {
+		if (lck)
+			unlock_cfg();
+		throw error;
+	}
 
 	if (lck)
 		unlock_cfg();