1# Copyright (c) 2004-2006 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: Steve Reinhardt
28# Nathan Binkert
29
30#####################################################################
31#
32# Proxy object support.
33#
34#####################################################################
35
36class BaseProxy(object):
37 def __init__(self, search_self, search_up):
38 self._search_self = search_self
39 self._search_up = search_up
40 self._multiplier = None
41
42 def __setattr__(self, attr, value):
43 if not attr.startswith('_'):
44 raise AttributeError, \
45 "cannot set attribute '%s' on proxy object" % attr
46 super(BaseProxy, self).__setattr__(attr, value)
47
48 # support multiplying proxies by constants
49 def __mul__(self, other):
50 if not isinstance(other, (int, long, float)):
51 raise TypeError, "Proxy multiplier must be integer"
52 if self._multiplier == None:
53 self._multiplier = other
54 else:
55 # support chained multipliers
56 self._multiplier *= other
57 return self
58
59 __rmul__ = __mul__
60
61 def _mulcheck(self, result):
62 if self._multiplier == None:
63 return result
64 return result * self._multiplier
65
66 def unproxy(self, base):
67 obj = base
68 done = False
69
70 if self._search_self:
71 result, done = self.find(obj)
72
73 if self._search_up:
74 while not done:
75 obj = obj._parent
76 if not obj:
77 break
78 result, done = self.find(obj)
79
80 if not done:
81 raise AttributeError, \
82 "Can't resolve proxy '%s' of type '%s' from '%s'" % \
83 (self.path(), self._pdesc.ptype_str, base.path())
84
85 if isinstance(result, BaseProxy):
86 if result == self:
87 raise RuntimeError, "Cycle in unproxy"
88 result = result.unproxy(obj)
89
90 return self._mulcheck(result)
91
92 def getindex(obj, index):
93 if index == None:
94 return obj
95 try:
96 obj = obj[index]
97 except TypeError:
98 if index != 0:
99 raise
100 # if index is 0 and item is not subscriptable, just
101 # use item itself (so cpu[0] works on uniprocessors)
102 return obj
103 getindex = staticmethod(getindex)
104
105 def set_param_desc(self, pdesc):
106 self._pdesc = pdesc
107
108class AttrProxy(BaseProxy):
109 def __init__(self, search_self, search_up, attr):
110 super(AttrProxy, self).__init__(search_self, search_up)
111 self._attr = attr
112 self._modifiers = []
113
114 def __getattr__(self, attr):
115 # python uses __bases__ internally for inheritance
116 if attr.startswith('_'):
117 return super(AttrProxy, self).__getattr__(self, attr)
118 if hasattr(self, '_pdesc'):
119 raise AttributeError, "Attribute reference on bound proxy"
120 self._modifiers.append(attr)
121 return self
122
123 # support indexing on proxies (e.g., Self.cpu[0])
124 def __getitem__(self, key):
125 if not isinstance(key, int):
126 raise TypeError, "Proxy object requires integer index"
127 self._modifiers.append(key)
128 return self
129
130 def find(self, obj):
131 try:
132 val = getattr(obj, self._attr)
133 except:
134 return None, False
135 while isproxy(val):
136 val = val.unproxy(obj)
137 for m in self._modifiers:
138 if isinstance(m, str):
139 val = getattr(val, m)
140 elif isinstance(m, int):
141 val = val[m]
142 else:
143 assert("Item must be string or integer")
144 while isproxy(val):
145 val = val.unproxy(obj)
146 return val, True
147
148 def path(self):
149 p = self._attr
150 for m in self._modifiers:
151 if isinstance(m, str):
152 p += '.%s' % m
153 elif isinstance(m, int):
154 p += '[%d]' % m
155 else:
156 assert("Item must be string or integer")
157 return p
158
159class AnyProxy(BaseProxy):
160 def find(self, obj):
161 return obj.find_any(self._pdesc.ptype)
162
163 def path(self):
164 return 'any'
165
166def isproxy(obj):
167 if isinstance(obj, (BaseProxy, params.EthernetAddr)):
168 return True
169 elif isinstance(obj, (list, tuple)):
170 for v in obj:
171 if isproxy(v):
172 return True
173 return False
174
175class ProxyFactory(object):
176 def __init__(self, search_self, search_up):
177 self.search_self = search_self
178 self.search_up = search_up
179
180 def __getattr__(self, attr):
181 if attr == 'any':
182 return AnyProxy(self.search_self, self.search_up)
183 else:
184 return AttrProxy(self.search_self, self.search_up, attr)
185
186# global objects for handling proxies
187Parent = ProxyFactory(search_self = False, search_up = True)
188Self = ProxyFactory(search_self = True, search_up = False)
189
190# limit exports on 'from proxy import *'
191__all__ = ['Parent', 'Self']
192
193# see comment on imports at end of __init__.py.
194import params # for EthernetAddr