1#!/usr/bin/env python2
2
3"""Find Kconfig symbols that are referenced but not defined."""
4
5# (c) 2014-2015 Valentin Rothberg <valentinrothberg@gmail.com>
6# (c) 2014 Stefan Hengelein <stefan.hengelein@fau.de>
7#
8# Licensed under the terms of the GNU GPL License version 2
9
10
11import difflib
12import os
13import re
14import signal
15import sys
16from multiprocessing import Pool, cpu_count
17from optparse import OptionParser
18from subprocess import Popen, PIPE, STDOUT
19
20
21# regex expressions
22OPERATORS = r"&|\(|\)|\||\!"
23FEATURE = r"(?:\w*[A-Z0-9]\w*){2,}"
24DEF = r"^\s*(?:menu){,1}config\s+(" + FEATURE + r")\s*"
25EXPR = r"(?:" + OPERATORS + r"|\s|" + FEATURE + r")+"
26DEFAULT = r"default\s+.*?(?:if\s.+){,1}"
27STMT = r"^\s*(?:if|select|depends\s+on|(?:" + DEFAULT + r"))\s+" + EXPR
28SOURCE_FEATURE = r"(?:\W|\b)+[D]{,1}CONFIG_(" + FEATURE + r")"
29
30# regex objects
31REGEX_FILE_KCONFIG = re.compile(r".*Kconfig[\.\w+\-]*$")
32REGEX_FEATURE = re.compile(r'(?!\B)' + FEATURE + r'(?!\B)')
33REGEX_SOURCE_FEATURE = re.compile(SOURCE_FEATURE)
34REGEX_KCONFIG_DEF = re.compile(DEF)
35REGEX_KCONFIG_EXPR = re.compile(EXPR)
36REGEX_KCONFIG_STMT = re.compile(STMT)
37REGEX_KCONFIG_HELP = re.compile(r"^\s+(help|---help---)\s*$")
38REGEX_FILTER_FEATURES = re.compile(r"[A-Za-z0-9]$")
39REGEX_NUMERIC = re.compile(r"0[xX][0-9a-fA-F]+|[0-9]+")
40REGEX_QUOTES = re.compile("(\"(.*?)\")")
41
42
43def parse_options():
44    """The user interface of this module."""
45    usage = "%prog [options]\n\n"                                              \
46            "Run this tool to detect Kconfig symbols that are referenced but " \
47            "not defined in\nKconfig.  The output of this tool has the "       \
48            "format \'Undefined symbol\\tFile list\'\n\n"                      \
49            "If no option is specified, %prog will default to check your\n"    \
50            "current tree.  Please note that specifying commits will "         \
51            "\'git reset --hard\'\nyour current tree!  You may save "          \
52            "uncommitted changes to avoid losing data."
53
54    parser = OptionParser(usage=usage)
55
56    parser.add_option('-c', '--commit', dest='commit', action='store',
57                      default="",
58                      help="Check if the specified commit (hash) introduces "
59                           "undefined Kconfig symbols.")
60
61    parser.add_option('-d', '--diff', dest='diff', action='store',
62                      default="",
63                      help="Diff undefined symbols between two commits.  The "
64                           "input format bases on Git log's "
65                           "\'commmit1..commit2\'.")
66
67    parser.add_option('-f', '--find', dest='find', action='store_true',
68                      default=False,
69                      help="Find and show commits that may cause symbols to be "
70                           "missing.  Required to run with --diff.")
71
72    parser.add_option('-i', '--ignore', dest='ignore', action='store',
73                      default="",
74                      help="Ignore files matching this pattern.  Note that "
75                           "the pattern needs to be a Python regex.  To "
76                           "ignore defconfigs, specify -i '.*defconfig'.")
77
78    parser.add_option('-s', '--sim', dest='sim', action='store', default="",
79                      help="Print a list of maximum 10 string-similar symbols.")
80
81    parser.add_option('', '--force', dest='force', action='store_true',
82                      default=False,
83                      help="Reset current Git tree even when it's dirty.")
84
85    (opts, _) = parser.parse_args()
86
87    if opts.commit and opts.diff:
88        sys.exit("Please specify only one option at once.")
89
90    if opts.diff and not re.match(r"^[\w\-\.]+\.\.[\w\-\.]+$", opts.diff):
91        sys.exit("Please specify valid input in the following format: "
92                 "\'commit1..commit2\'")
93
94    if opts.commit or opts.diff:
95        if not opts.force and tree_is_dirty():
96            sys.exit("The current Git tree is dirty (see 'git status').  "
97                     "Running this script may\ndelete important data since it "
98                     "calls 'git reset --hard' for some performance\nreasons. "
99                     " Please run this script in a clean Git tree or pass "
100                     "'--force' if you\nwant to ignore this warning and "
101                     "continue.")
102
103    if opts.commit:
104        opts.find = False
105
106    if opts.ignore:
107        try:
108            re.match(opts.ignore, "this/is/just/a/test.c")
109        except:
110            sys.exit("Please specify a valid Python regex.")
111
112    return opts
113
114
115def main():
116    """Main function of this module."""
117    opts = parse_options()
118
119    if opts.sim and not opts.commit and not opts.diff:
120        sims = find_sims(opts.sim, opts.ignore)
121        if sims:
122            print "%s: %s" % (yel("Similar symbols"), ', '.join(sims))
123        else:
124            print "%s: no similar symbols found" % yel("Similar symbols")
125        sys.exit(0)
126
127    # dictionary of (un)defined symbols
128    defined = {}
129    undefined = {}
130
131    if opts.commit or opts.diff:
132        head = get_head()
133
134        # get commit range
135        commit_a = None
136        commit_b = None
137        if opts.commit:
138            commit_a = opts.commit + "~"
139            commit_b = opts.commit
140        elif opts.diff:
141            split = opts.diff.split("..")
142            commit_a = split[0]
143            commit_b = split[1]
144            undefined_a = {}
145            undefined_b = {}
146
147        # get undefined items before the commit
148        execute("git reset --hard %s" % commit_a)
149        undefined_a, _ = check_symbols(opts.ignore)
150
151        # get undefined items for the commit
152        execute("git reset --hard %s" % commit_b)
153        undefined_b, defined = check_symbols(opts.ignore)
154
155        # report cases that are present for the commit but not before
156        for feature in sorted(undefined_b):
157            # feature has not been undefined before
158            if not feature in undefined_a:
159                files = sorted(undefined_b.get(feature))
160                undefined[feature] = files
161            # check if there are new files that reference the undefined feature
162            else:
163                files = sorted(undefined_b.get(feature) -
164                               undefined_a.get(feature))
165                if files:
166                    undefined[feature] = files
167
168        # reset to head
169        execute("git reset --hard %s" % head)
170
171    # default to check the entire tree
172    else:
173        undefined, defined = check_symbols(opts.ignore)
174
175    # now print the output
176    for feature in sorted(undefined):
177        print red(feature)
178
179        files = sorted(undefined.get(feature))
180        print "%s: %s" % (yel("Referencing files"), ", ".join(files))
181
182        sims = find_sims(feature, opts.ignore, defined)
183        sims_out = yel("Similar symbols")
184        if sims:
185            print "%s: %s" % (sims_out, ', '.join(sims))
186        else:
187            print "%s: %s" % (sims_out, "no similar symbols found")
188
189        if opts.find:
190            print "%s:" % yel("Commits changing symbol")
191            commits = find_commits(feature, opts.diff)
192            if commits:
193                for commit in commits:
194                    commit = commit.split(" ", 1)
195                    print "\t- %s (\"%s\")" % (yel(commit[0]), commit[1])
196            else:
197                print "\t- no commit found"
198        print  #  new line
199
200
201def yel(string):
202    """
203    Color %string yellow.
204    """
205    return "\033[33m%s\033[0m" % string
206
207
208def red(string):
209    """
210    Color %string red.
211    """
212    return "\033[31m%s\033[0m" % string
213
214
215def execute(cmd):
216    """Execute %cmd and return stdout.  Exit in case of error."""
217    pop = Popen(cmd, stdout=PIPE, stderr=STDOUT, shell=True)
218    (stdout, _) = pop.communicate()  # wait until finished
219    if pop.returncode != 0:
220        sys.exit(stdout)
221    return stdout
222
223
224def find_commits(symbol, diff):
225    """Find commits changing %symbol in the given range of %diff."""
226    commits = execute("git log --pretty=oneline --abbrev-commit -G %s %s"
227                      % (symbol, diff))
228    return [x for x in commits.split("\n") if x]
229
230
231def tree_is_dirty():
232    """Return true if the current working tree is dirty (i.e., if any file has
233    been added, deleted, modified, renamed or copied but not committed)."""
234    stdout = execute("git status --porcelain")
235    for line in stdout:
236        if re.findall(r"[URMADC]{1}", line[:2]):
237            return True
238    return False
239
240
241def get_head():
242    """Return commit hash of current HEAD."""
243    stdout = execute("git rev-parse HEAD")
244    return stdout.strip('\n')
245
246
247def partition(lst, size):
248    """Partition list @lst into eveni-sized lists of size @size."""
249    return [lst[i::size] for i in xrange(size)]
250
251
252def init_worker():
253    """Set signal handler to ignore SIGINT."""
254    signal.signal(signal.SIGINT, signal.SIG_IGN)
255
256
257def find_sims(symbol, ignore, defined = []):
258    """Return a list of max. ten Kconfig symbols that are string-similar to
259    @symbol."""
260    if defined:
261        return sorted(difflib.get_close_matches(symbol, set(defined), 10))
262
263    pool = Pool(cpu_count(), init_worker)
264    kfiles = []
265    for gitfile in get_files():
266        if REGEX_FILE_KCONFIG.match(gitfile):
267            kfiles.append(gitfile)
268
269    arglist = []
270    for part in partition(kfiles, cpu_count()):
271        arglist.append((part, ignore))
272
273    for res in pool.map(parse_kconfig_files, arglist):
274        defined.extend(res[0])
275
276    return sorted(difflib.get_close_matches(symbol, set(defined), 10))
277
278
279def get_files():
280    """Return a list of all files in the current git directory."""
281    # use 'git ls-files' to get the worklist
282    stdout = execute("git ls-files")
283    if len(stdout) > 0 and stdout[-1] == "\n":
284        stdout = stdout[:-1]
285
286    files = []
287    for gitfile in stdout.rsplit("\n"):
288        if ".git" in gitfile or "ChangeLog" in gitfile or      \
289                ".log" in gitfile or os.path.isdir(gitfile) or \
290                gitfile.startswith("tools/"):
291            continue
292        files.append(gitfile)
293    return files
294
295
296def check_symbols(ignore):
297    """Find undefined Kconfig symbols and return a dict with the symbol as key
298    and a list of referencing files as value.  Files matching %ignore are not
299    checked for undefined symbols."""
300    pool = Pool(cpu_count(), init_worker)
301    try:
302        return check_symbols_helper(pool, ignore)
303    except KeyboardInterrupt:
304        pool.terminate()
305        pool.join()
306        sys.exit(1)
307
308
309def check_symbols_helper(pool, ignore):
310    """Helper method for check_symbols().  Used to catch keyboard interrupts in
311    check_symbols() in order to properly terminate running worker processes."""
312    source_files = []
313    kconfig_files = []
314    defined_features = []
315    referenced_features = dict()  # {file: [features]}
316
317    for gitfile in get_files():
318        if REGEX_FILE_KCONFIG.match(gitfile):
319            kconfig_files.append(gitfile)
320        else:
321            if ignore and not re.match(ignore, gitfile):
322                continue
323            # add source files that do not match the ignore pattern
324            source_files.append(gitfile)
325
326    # parse source files
327    arglist = partition(source_files, cpu_count())
328    for res in pool.map(parse_source_files, arglist):
329        referenced_features.update(res)
330
331
332    # parse kconfig files
333    arglist = []
334    for part in partition(kconfig_files, cpu_count()):
335        arglist.append((part, ignore))
336    for res in pool.map(parse_kconfig_files, arglist):
337        defined_features.extend(res[0])
338        referenced_features.update(res[1])
339    defined_features = set(defined_features)
340
341    # inverse mapping of referenced_features to dict(feature: [files])
342    inv_map = dict()
343    for _file, features in referenced_features.iteritems():
344        for feature in features:
345            inv_map[feature] = inv_map.get(feature, set())
346            inv_map[feature].add(_file)
347    referenced_features = inv_map
348
349    undefined = {}  # {feature: [files]}
350    for feature in sorted(referenced_features):
351        # filter some false positives
352        if feature == "FOO" or feature == "BAR" or \
353                feature == "FOO_BAR" or feature == "XXX":
354            continue
355        if feature not in defined_features:
356            if feature.endswith("_MODULE"):
357                # avoid false positives for kernel modules
358                if feature[:-len("_MODULE")] in defined_features:
359                    continue
360            undefined[feature] = referenced_features.get(feature)
361    return undefined, defined_features
362
363
364def parse_source_files(source_files):
365    """Parse each source file in @source_files and return dictionary with source
366    files as keys and lists of references Kconfig symbols as values."""
367    referenced_features = dict()
368    for sfile in source_files:
369        referenced_features[sfile] = parse_source_file(sfile)
370    return referenced_features
371
372
373def parse_source_file(sfile):
374    """Parse @sfile and return a list of referenced Kconfig features."""
375    lines = []
376    references = []
377
378    if not os.path.exists(sfile):
379        return references
380
381    with open(sfile, "r") as stream:
382        lines = stream.readlines()
383
384    for line in lines:
385        if not "CONFIG_" in line:
386            continue
387        features = REGEX_SOURCE_FEATURE.findall(line)
388        for feature in features:
389            if not REGEX_FILTER_FEATURES.search(feature):
390                continue
391            references.append(feature)
392
393    return references
394
395
396def get_features_in_line(line):
397    """Return mentioned Kconfig features in @line."""
398    return REGEX_FEATURE.findall(line)
399
400
401def parse_kconfig_files(args):
402    """Parse kconfig files and return tuple of defined and references Kconfig
403    symbols.  Note, @args is a tuple of a list of files and the @ignore
404    pattern."""
405    kconfig_files = args[0]
406    ignore = args[1]
407    defined_features = []
408    referenced_features = dict()
409
410    for kfile in kconfig_files:
411        defined, references = parse_kconfig_file(kfile)
412        defined_features.extend(defined)
413        if ignore and re.match(ignore, kfile):
414            # do not collect references for files that match the ignore pattern
415            continue
416        referenced_features[kfile] = references
417    return (defined_features, referenced_features)
418
419
420def parse_kconfig_file(kfile):
421    """Parse @kfile and update feature definitions and references."""
422    lines = []
423    defined = []
424    references = []
425    skip = False
426
427    if not os.path.exists(kfile):
428        return defined, references
429
430    with open(kfile, "r") as stream:
431        lines = stream.readlines()
432
433    for i in range(len(lines)):
434        line = lines[i]
435        line = line.strip('\n')
436        line = line.split("#")[0]  # ignore comments
437
438        if REGEX_KCONFIG_DEF.match(line):
439            feature_def = REGEX_KCONFIG_DEF.findall(line)
440            defined.append(feature_def[0])
441            skip = False
442        elif REGEX_KCONFIG_HELP.match(line):
443            skip = True
444        elif skip:
445            # ignore content of help messages
446            pass
447        elif REGEX_KCONFIG_STMT.match(line):
448            line = REGEX_QUOTES.sub("", line)
449            features = get_features_in_line(line)
450            # multi-line statements
451            while line.endswith("\\"):
452                i += 1
453                line = lines[i]
454                line = line.strip('\n')
455                features.extend(get_features_in_line(line))
456            for feature in set(features):
457                if REGEX_NUMERIC.match(feature):
458                    # ignore numeric values
459                    continue
460                references.append(feature)
461
462    return defined, references
463
464
465if __name__ == "__main__":
466    main()
467