SysPaths.py revision 10759:37fd40f8300f 
1# Copyright (c) 2006 The Regents of The University of Michigan
2# All rights reserved.
3#
4# Redistribution and use in source and binary forms, with or without
5# modification, are permitted provided that the following conditions are
6# met: redistributions of source code must retain the above copyright
7# notice, this list of conditions and the following disclaimer;
8# redistributions in binary form must reproduce the above copyright
9# notice, this list of conditions and the following disclaimer in the
10# documentation and/or other materials provided with the distribution;
11# neither the name of the copyright holders nor the names of its
12# contributors may be used to endorse or promote products derived from
13# this software without specific prior written permission.
14#
15# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26#
27# Authors: Ali Saidi
28
29import os, sys
30from os.path import join as joinpath
31from os import environ as env
32
33config_path = os.path.dirname(os.path.abspath(__file__))
34config_root = os.path.dirname(config_path)
35
36def searchpath(path, filename):
37    for p in path:
38        f = joinpath(p, filename)
39        if os.path.exists(f):
40            return f
41    raise IOError, "Can't find file '%s' on path." % filename
42
43def disk(filename):
44    system()
45    return searchpath(disk.path, filename)
46
47def binary(filename):
48    system()
49    return searchpath(binary.path, filename)
50
51def script(filename):
52    system()
53    return searchpath(script.path, filename)
54
55def system():
56    if not system.path:
57        try:
58            path = env['M5_PATH'].split(':')
59        except KeyError:
60            path = [ '/dist/m5/system', '/n/poolfs/z/dist/m5/system' ]
61
62        # expand '~' and '~user' in paths
63        path = map(os.path.expanduser, path)
64
65        # filter out non-existent directories
66        system.path = filter(os.path.isdir, path)
67
68        if not system.path:
69            raise IOError, "Can't find a path to system files."
70
71    if not binary.path:
72        binary.path = [joinpath(p, 'binaries') for p in system.path]
73    if not disk.path:
74        disk.path = [joinpath(p, 'disks') for p in system.path]
75    if not script.path:
76        script.path = [joinpath(config_root, 'boot')]
77
78system.path = None
79binary.path = None
80disk.path = None
81script.path = None
82