merge-event-log-tags.py revision 6ce87a1fc87873510e571c08d5995773a16cddf1 
1#!/usr/bin/env python
2#
3# Copyright (C) 2009 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17"""
18Usage: merge-event-log-tags.py [-o output_file] [input_files...]
19
20Merge together zero or more event-logs-tags files to produce a single
21output file, stripped of comments.  Checks that no tag numbers conflict
22and fails if they do.
23
24-h to display this usage message and exit.
25"""
26
27import cStringIO
28import getopt
29try:
30  import hashlib
31except ImportError:
32  import md5 as hashlib
33import struct
34import sys
35
36import event_log_tags
37
38errors = []
39warnings = []
40
41output_file = None
42pre_merged_file = None
43
44# Tags with a tag number of ? are assigned a tag in the range
45# [ASSIGN_START, ASSIGN_LIMIT).
46ASSIGN_START = 900000
47ASSIGN_LIMIT = 1000000
48
49try:
50  opts, args = getopt.getopt(sys.argv[1:], "ho:m:")
51except getopt.GetoptError, err:
52  print str(err)
53  print __doc__
54  sys.exit(2)
55
56for o, a in opts:
57  if o == "-h":
58    print __doc__
59    sys.exit(2)
60  elif o == "-o":
61    output_file = a
62  elif o == "-m":
63    pre_merged_file = a
64  else:
65    print >> sys.stderr, "unhandled option %s" % (o,)
66    sys.exit(1)
67
68# Restrictions on tags:
69#
70#   Tag names must be unique.  (If the tag number and description are
71#   also the same, a warning is issued instead of an error.)
72#
73#   Explicit tag numbers must be unique.  (If the tag name is also the
74#   same, no error is issued because the above rule will issue a
75#   warning or error.)
76
77by_tagname = {}
78by_tagnum = {}
79
80pre_merged_tags = {}
81if pre_merged_file:
82  for t in event_log_tags.TagFile(pre_merged_file).tags:
83    pre_merged_tags[t.tagname] = t
84
85for fn in args:
86  tagfile = event_log_tags.TagFile(fn)
87
88  for t in tagfile.tags:
89    tagnum = t.tagnum
90    tagname = t.tagname
91    description = t.description
92
93    if t.tagname in by_tagname:
94      orig = by_tagname[t.tagname]
95
96      # Allow an explicit tag number to define an implicit tag number
97      if orig.tagnum is None:
98        orig.tagnum = t.tagnum
99      elif t.tagnum is None:
100        t.tagnum = orig.tagnum
101
102      if (t.tagnum == orig.tagnum and
103          t.description == orig.description):
104        # if the name and description are identical, issue a warning
105        # instead of failing (to make it easier to move tags between
106        # projects without breaking the build).
107        tagfile.AddWarning("tag \"%s\" (%s) duplicated in %s:%d" %
108                           (t.tagname, t.tagnum, orig.filename, orig.linenum),
109                           linenum=t.linenum)
110      else:
111        tagfile.AddError(
112            "tag name \"%s\" used by conflicting tag %s from %s:%d" %
113            (t.tagname, orig.tagnum, orig.filename, orig.linenum),
114            linenum=t.linenum)
115      continue
116
117    if t.tagnum is not None and t.tagnum in by_tagnum:
118      orig = by_tagnum[t.tagnum]
119
120      if t.tagname != orig.tagname:
121        tagfile.AddError(
122            "tag number %d used by conflicting tag \"%s\" from %s:%d" %
123            (t.tagnum, orig.tagname, orig.filename, orig.linenum),
124            linenum=t.linenum)
125        continue
126
127    by_tagname[t.tagname] = t
128    if t.tagnum is not None:
129      by_tagnum[t.tagnum] = t
130
131  errors.extend(tagfile.errors)
132  warnings.extend(tagfile.warnings)
133
134if errors:
135  for fn, ln, msg in errors:
136    print >> sys.stderr, "%s:%d: error: %s" % (fn, ln, msg)
137  sys.exit(1)
138
139if warnings:
140  for fn, ln, msg in warnings:
141    print >> sys.stderr, "%s:%d: warning: %s" % (fn, ln, msg)
142
143# Python's hash function (a) isn't great and (b) varies between
144# versions of python.  Using md5 is overkill here but is the same from
145# platform to platform and speed shouldn't matter in practice.
146def hashname(str):
147  d = hashlib.md5(str).digest()[:4]
148  return struct.unpack("!I", d)[0]
149
150# Assign a tag number to all the entries that say they want one
151# assigned.  We do this based on a hash of the tag name so that the
152# numbers should stay relatively stable as tags are added.
153
154# If we were provided pre-merged tags (w/ the -m option), then don't
155# ever try to allocate one, just fail if we don't have a number
156
157for name, t in sorted(by_tagname.iteritems()):
158  if t.tagnum is None:
159    if pre_merged_tags:
160      try:
161        t.tagnum = pre_merged_tags[t.tagname]
162      except KeyError:
163        print >> sys.stderr, ("Error: Tag number not defined for tag `%s'."
164            +" Have you done a full build?") % t.tagname
165        sys.exit(1)
166    else:
167      while True:
168        x = (hashname(name) % (ASSIGN_LIMIT - ASSIGN_START - 1)) + ASSIGN_START
169        if x not in by_tagnum:
170          t.tagnum = x
171          by_tagnum[x] = t
172          break
173        name = "_" + name
174
175# by_tagnum should be complete now; we've assigned numbers to all tags.
176
177buffer = cStringIO.StringIO()
178for n, t in sorted(by_tagnum.iteritems()):
179  if t.description:
180    buffer.write("%d %s %s\n" % (t.tagnum, t.tagname, t.description))
181  else:
182    buffer.write("%d %s\n" % (t.tagnum, t.tagname))
183
184event_log_tags.WriteOutput(output_file, buffer)
185