1#!/usr/bin/env python2.7
2
3# Copyright (c) 2012-2013,2015-2016 ARM Limited
4# All rights reserved
5#
6# The license below extends only to copyright in the software and shall
7# not be construed as granting a license to any other intellectual
8# property including but not limited to intellectual property relating
9# to a hardware implementation of the functionality of the software
10# licensed hereunder.  You may use the software subject to the license
11# terms below provided that you ensure that this notice is replicated
12# unmodified and in its entirety in all distributions of the software,
13# modified or unmodified, in source code or in binary form.
14#
15# Redistribution and use in source and binary forms, with or without
16# modification, are permitted provided that the following conditions are
17# met: redistributions of source code must retain the above copyright
18# notice, this list of conditions and the following disclaimer;
19# redistributions in binary form must reproduce the above copyright
20# notice, this list of conditions and the following disclaimer in the
21# documentation and/or other materials provided with the distribution;
22# neither the name of the copyright holders nor the names of its
23# contributors may be used to endorse or promote products derived from
24# this software without specific prior written permission.
25#
26# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
27# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
28# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
29# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
30# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
36# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37#
38# Authors: Ali Saidi
39#          Curtis Dunham
40#
41
42# This python code is used to migrate checkpoints that were created in one
43# version of the simulator to newer version. As features are added or bugs are
44# fixed some of the state that needs to be checkpointed can change. If you have
45# many historic checkpoints that you use, manually editing them to fix them is
46# both time consuming and error-prone.
47
48# This script provides a way to migrate checkpoints to the newer repository in
49# a programmatic way. It can be imported into another script or used on the
50# command line. From the command line the script will either migrate every
51# checkpoint it finds recursively (-r option) or a single checkpoint. When a
52# change is made to the gem5 repository that breaks previous checkpoints an
53# upgrade() method should be implemented in its own .py file and placed in
54# src/util/cpt_upgraders/.  For each upgrader whose tag is not present in
55# the checkpoint tag list, the upgrade() method will be run, passing in a
56# ConfigParser object which contains the open file. As these operations can
57# be isa specific the method can verify the isa and use regexes to find the
58# correct sections that need to be updated.
59
60# It is also possible to use this mechanism to revert prior tags.  In this
61# case, implement a downgrade() method instead.  Dependencies should still
62# work naturally - a tag depending on a tag with a downgrader means that it
63# insists on the other tag being removed and its downgrader executed before
64# its upgrader (or downgrader) can run.  It is still the case that a tag
65# can only be used once.
66
67# Dependencies between tags are expressed by two variables at the top-level
68# of the upgrader script: "depends" can be either a string naming another
69# tag that it depends upon or a list of such strings; and "fwd_depends"
70# accepts the same datatypes but it reverses the sense of the dependency
71# arrow(s) -- it expresses that that tag depends upon the tag of the current
72# upgrader. This can be especially valuable when maintaining private
73# upgraders in private branches.
74
75
76import ConfigParser
77import glob, types, sys, os
78import os.path as osp
79
80verbose_print = False
81
82def verboseprint(*args):
83    if not verbose_print:
84        return
85    for arg in args:
86        print arg,
87    print
88
89class Upgrader:
90    tag_set = set()
91    untag_set = set() # tags to remove by downgrading
92    by_tag = {}
93    legacy = {}
94    def __init__(self, filename):
95        self.filename = filename
96        execfile(filename, {}, self.__dict__)
97
98        if not hasattr(self, 'tag'):
99            self.tag = osp.basename(filename)[:-3]
100        if not hasattr(self, 'depends'):
101            self.depends = []
102        elif isinstance(self.depends, str):
103            self.depends = [self.depends]
104
105        if not isinstance(self.depends, list):
106            print "Error: 'depends' for %s is the wrong type" % self.tag
107            sys.exit(1)
108
109        if hasattr(self, 'fwd_depends'):
110            if isinstance(self.fwd_depends, str):
111                self.fwd_depends = [self.fwd_depends]
112        else:
113            self.fwd_depends = []
114
115        if not isinstance(self.fwd_depends, list):
116            print "Error: 'fwd_depends' for %s is the wrong type" % self.tag
117            sys.exit(1)
118
119        if hasattr(self, 'upgrader'):
120            if not isinstance(self.upgrader, types.FunctionType):
121                print "Error: 'upgrader' for %s is %s, not function" \
122                    % (self.tag, type(self))
123                sys.exit(1)
124            Upgrader.tag_set.add(self.tag)
125        elif hasattr(self, 'downgrader'):
126            if not isinstance(self.downgrader, types.FunctionType):
127                print "Error: 'downgrader' for %s is %s, not function" \
128                    % (self.tag, type(self))
129                sys.exit(1)
130            Upgrader.untag_set.add(self.tag)
131        else:
132            print "Error: no upgrader or downgrader method for", self.tag
133            sys.exit(1)
134
135        if hasattr(self, 'legacy_version'):
136            Upgrader.legacy[self.legacy_version] = self
137
138        Upgrader.by_tag[self.tag] = self
139
140    def ready(self, tags):
141        for dep in self.depends:
142            if dep not in tags:
143                return False
144        return True
145
146    def update(self, cpt, tags):
147        if hasattr(self, 'upgrader'):
148            self.upgrader(cpt)
149            tags.add(self.tag)
150            verboseprint("applied upgrade for", self.tag)
151        else:
152            self.downgrader(cpt)
153            tags.remove(self.tag)
154            verboseprint("applied downgrade for", self.tag)
155
156    @staticmethod
157    def get(tag):
158        return Upgrader.by_tag[tag]
159
160    @staticmethod
161    def load_all():
162        util_dir = osp.dirname(osp.abspath(__file__))
163
164        for py in glob.glob(util_dir + '/cpt_upgraders/*.py'):
165            Upgrader(py)
166
167        # make linear dependences for legacy versions
168        i = 3
169        while i in Upgrader.legacy:
170            Upgrader.legacy[i].depends = [Upgrader.legacy[i-1].tag]
171            i = i + 1
172
173        # resolve forward dependencies and audit normal dependencies
174        for tag, upg in Upgrader.by_tag.items():
175            for fd in upg.fwd_depends:
176                if fd not in Upgrader.by_tag:
177                    print "Error: '%s' cannot (forward) depend on "\
178                          "nonexistent tag '%s'" % (fd, tag)
179                    sys.exit(1)
180                Upgrader.by_tag[fd].depends.append(tag)
181            for dep in upg.depends:
182                if dep not in Upgrader.by_tag:
183                    print "Error: '%s' cannot depend on "\
184                          "nonexistent tag '%s'" % (tag, dep)
185                    sys.exit(1)
186
187def process_file(path, **kwargs):
188    if not osp.isfile(path):
189        import errno
190        raise IOError(ennro.ENOENT, "No such file", path)
191
192    verboseprint("Processing file %s...." % path)
193
194    if kwargs.get('backup', True):
195        import shutil
196        shutil.copyfile(path, path + '.bak')
197
198    cpt = ConfigParser.SafeConfigParser()
199
200    # gem5 is case sensitive with paramaters
201    cpt.optionxform = str
202
203    # Read the current data
204    cpt_file = file(path, 'r')
205    cpt.readfp(cpt_file)
206    cpt_file.close()
207
208    change = False
209
210    # Make sure we know what we're starting from
211    if cpt.has_option('root','cpt_ver'):
212        cpt_ver = cpt.getint('root','cpt_ver')
213
214        # Legacy linear checkpoint version
215        # convert to list of tags before proceeding
216        tags = set([])
217        for i in xrange(2, cpt_ver+1):
218            tags.add(Upgrader.legacy[i].tag)
219        verboseprint("performed legacy version -> tags conversion")
220        change = True
221
222        cpt.remove_option('root', 'cpt_ver')
223    elif cpt.has_option('Globals','version_tags'):
224        tags = set((''.join(cpt.get('Globals','version_tags'))).split())
225    else:
226        print "fatal: no version information in checkpoint"
227        exit(1)
228
229    verboseprint("has tags", ' '.join(tags))
230    # If the current checkpoint has a tag we don't know about, we have
231    # a divergence that (in general) must be addressed by (e.g.) merging
232    # simulator support for its changes.
233    unknown_tags = tags - (Upgrader.tag_set | Upgrader.untag_set)
234    if unknown_tags:
235        print "warning: upgrade script does not recognize the following "\
236              "tags in this checkpoint:", ' '.join(unknown_tags)
237
238    # Apply migrations for tags not in checkpoint and tags present for which
239    # downgraders are present, respecting dependences
240    to_apply = (Upgrader.tag_set - tags) | (Upgrader.untag_set & tags)
241    while to_apply:
242        ready = set([ t for t in to_apply if Upgrader.get(t).ready(tags) ])
243        if not ready:
244            print "could not apply these upgrades:", ' '.join(to_apply)
245            print "update dependences impossible to resolve; aborting"
246            exit(1)
247
248        for tag in ready:
249            Upgrader.get(tag).update(cpt, tags)
250            change = True
251
252        to_apply -= ready
253
254    if not change:
255        verboseprint("...nothing to do")
256        return
257
258    cpt.set('Globals', 'version_tags', ' '.join(tags))
259
260    # Write the old data back
261    verboseprint("...completed")
262    cpt.write(file(path, 'w'))
263
264if __name__ == '__main__':
265    from optparse import OptionParser, SUPPRESS_HELP
266    parser = OptionParser("usage: %prog [options] <filename or directory>")
267    parser.add_option("-r", "--recurse", action="store_true",
268                      help="Recurse through all subdirectories modifying "\
269                           "each checkpoint that is found")
270    parser.add_option("-N", "--no-backup", action="store_false",
271                      dest="backup", default=True,
272                      help="Do no backup each checkpoint before modifying it")
273    parser.add_option("-v", "--verbose", action="store_true",
274                      help="Print out debugging information as")
275    parser.add_option("--get-cc-file", action="store_true",
276                      # used during build; generate src/sim/tags.cc and exit
277                      help=SUPPRESS_HELP)
278
279    (options, args) = parser.parse_args()
280    verbose_print = options.verbose
281
282    Upgrader.load_all()
283
284    if options.get_cc_file:
285        print "// this file is auto-generated by util/cpt_upgrader.py"
286        print "#include <string>"
287        print "#include <set>"
288        print
289        print "std::set<std::string> version_tags = {"
290        for tag in Upgrader.tag_set:
291            print "  \"%s\"," % tag
292        print "};"
293        exit(0)
294    elif len(args) != 1:
295        parser.error("You must specify a checkpoint file to modify or a "\
296                     "directory of checkpoints to recursively update")
297
298    # Deal with shell variables and ~
299    path = osp.expandvars(osp.expanduser(args[0]))
300
301    # Process a single file if we have it
302    if osp.isfile(path):
303        process_file(path, **vars(options))
304    # Process an entire directory
305    elif osp.isdir(path):
306        cpt_file = osp.join(path, 'm5.cpt')
307        if options.recurse:
308            # Visit very file and see if it matches
309            for root,dirs,files in os.walk(path):
310                for name in files:
311                    if name == 'm5.cpt':
312                        process_file(osp.join(root,name), **vars(options))
313                for dir in dirs:
314                    pass
315        # Maybe someone passed a cpt.XXXXXXX directory and not m5.cpt
316        elif osp.isfile(cpt_file):
317            process_file(cpt_file, **vars(options))
318        else:
319            print "Error: checkpoint file not found at in %s " % path,
320            print "and recurse not specified"
321            sys.exit(1)
322    sys.exit(0)
323
324