Added proxy nodes, optimized node management policy

Now, when 'file,,x' is requested, nsmux will create a proxy
node and will set the translator 'x' on this node, not on
the real filesystem node. Also, nsmux will not create nodes
for simple file looks, instead it will simply return the
port to the required file, thus avoiding the necessity
to handle IO operations inside itself.

1 files changed, 27 insertions, 1 deletions

diff --git a/lib.c b/lib.c
index aa0ff0be8..c05e08eae 100644
--- a/lib.c
+++ b/lib.c
@@ -5,7 +5,7 @@
 /*----------------------------------------------------------------------------*/
 /*Based on the code of unionfs translator.*/
 /*----------------------------------------------------------------------------*/
-/*Copyright (C) 2001, 2002, 2005 Free Software Foundation, Inc.
+/*Copyright (C) 2001, 2002, 2005, 2008 Free Software Foundation, Inc.
   Written by Sergiu Ivanov <unlimitedscolobb@gmail.com>.
 
   This program is free software; you can redistribute it and/or
@@ -28,6 +28,8 @@
 #define _GNU_SOURCE 1
 /*----------------------------------------------------------------------------*/
 #include <sys/mman.h>
+#include <fcntl.h>
+#include <hurd/fshelp.h>
 /*----------------------------------------------------------------------------*/
 #include "lib.h"
 #include "debug.h"
@@ -191,3 +193,27 @@ file_lookup
 	return err;
 	}/*file_lookup*/
 /*----------------------------------------------------------------------------*/
+/*Checks whether `user` has the right to open the node described by `stat` with
+	`flags`*/
+error_t
+check_open_permissions
+	(
+	struct iouser * user,
+	io_statbuf_t * stat,
+	int flags
+	)
+	{
+	error_t err = 0;
+	
+	/*Cheks user's permissions*/
+	if(flags & O_READ)
+		err = fshelp_access(stat, S_IREAD, user);
+	if(!err && (flags & O_WRITE))
+		err = fshelp_access(stat, S_IWRITE, user);
+	if(!err && (flags & O_EXEC))
+		err = fshelp_access(stat, S_IEXEC, user);
+		
+	/*Return the result of the check*/
+	return err;
+	}/*check_open_permissions*/
+/*----------------------------------------------------------------------------*/