SysPaths.py revision 12233:53cf2e32cb59 
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
30
31config_path = os.path.dirname(os.path.abspath(__file__))
32config_root = os.path.dirname(config_path)
33
34class PathSearchFunc(object):
35    _sys_paths = None
36
37    def __init__(self, *subdirs):
38        self._subdir = os.path.join(*subdirs)
39
40    def __call__(self, filename):
41        if self._sys_paths is None:
42            try:
43                paths = os.environ['M5_PATH'].split(':')
44            except KeyError:
45                paths = [ '/dist/m5/system', '/n/poolfs/z/dist/m5/system' ]
46
47            # expand '~' and '~user' in paths
48            paths = map(os.path.expanduser, paths)
49
50            # filter out non-existent directories
51            paths = filter(os.path.isdir, paths)
52
53            if not paths:
54                raise IOError, "Can't find a path to system files."
55
56            self._sys_paths = paths
57
58        filepath = os.path.join(self._subdir, filename)
59        paths = (os.path.join(p, filepath) for p in self._sys_paths)
60        try:
61            return next(p for p in paths if os.path.exists(p))
62        except StopIteration:
63            raise IOError, "Can't find file '%s' on path." % filename
64
65disk = PathSearchFunc('disks')
66binary = PathSearchFunc('binaries')
67script = PathSearchFunc('boot')
68