move ADOdb row_lock and rollback_lock methods to Db class, use Db::$tablealiases and use them for backup, also added a "backup_(starts|finished)" hook for apps

api/src/Db.php

@@ -852,6 +852,70 @@ class Db
 		return $this->Link_ID->FailTrans();
 	}
 
+	/**
+	 * Lock a rows in table
+	 *
+	 * Will escalate and lock the table if row locking not supported.
+	 * Will normally free the lock at the end of the transaction.
+	 *
+	 * @param string $table name of table to lock
+	 * @param string $where ='true' where clause to use, eg: "WHERE row=12". Defaults to lock whole table.
+	 * @param string $col ='1 as adodbignore'
+	 */
+	function row_lock($table, $where='true', $col='1 as adodbignore')
+	{
+		if (!$this->Link_ID && !$this->connect())
+		{
+			return False;
+		}
+		if (self::$tablealiases && isset(self::$tablealiases[$table]))
+		{
+			$table = self::$tablealiases[$table];
+		}
+
+		return $this->Link_ID->RowLock($table, $where, $col);
+	}
+
+	/**
+	 * Commit changed rows in table
+	 *
+	 * @param string $table
+	 * @return boolean
+	 */
+	function commit_lock($table)
+	{
+		if (!$this->Link_ID && !$this->connect())
+		{
+			return False;
+		}
+		if (self::$tablealiases && isset(self::$tablealiases[$table]))
+		{
+			$table = self::$tablealiases[$table];
+		}
+
+		return $this->Link_ID->CommitLock($table);
+	}
+
+	/**
+	 * Unlock rows in table
+	 *
+	 * @param string $table
+	 * @return boolean
+	 */
+	function rollback_lock($table)
+	{
+		if (!$this->Link_ID && !$this->connect())
+		{
+			return False;
+		}
+		if (self::$tablealiases && isset(self::$tablealiases[$table]))
+		{
+			$table = self::$tablealiases[$table];
+		}
+
+		return $this->Link_ID->RollbackLock($table);
+	}
+
 	/**
 	* Find the primary key of the last insertion on the current db connection
 	*

api/src/Db/Backup.php

@@ -920,6 +920,9 @@ class Backup
 
 		fwrite($f,"\nschema: ".json_encode($this->schemas)."\n");
 
+		// let apps know that backup is about to start
+		Api\Hooks::process('backup_starts', array(), true);
+
 		foreach($this->schemas as $table => $schema)
 		{
 			if (in_array($table,$this->exclude_tables)) continue;	// dont backup
@@ -932,7 +935,7 @@ class Backup
 
 			if ($lock_table || empty($pk) && is_null($lock_table))
 			{
-				$this->db->Link_ID->RowLock($table, 'true');	// PostgreSQL drive from ADOdb requires 2. param $where!
+				$this->db->Link_ID->row_lock($table);
 			}
 			$total = $max = 0;
 			do {
@@ -959,8 +962,12 @@ class Backup
 			}
 			while((!empty($pk) || $lock_table !== false) && !($total % self::ROW_CHUNK) && $num_rows);
 
-			if (!$pk) $this->db->Link_ID->RollbackLock($table);
+			if (!$pk) $this->db->rollback_lock($table);
 		}
+
+		// let apps know that backup is finished
+		Api\Hooks::process('backup_finished', array(), true);
+
 		if(!$zippresent)  // save without files
 		{
 			if ($this->backup_files)