1#!/usr/bin/env python3
2
3"""Find Kconfig symbols that are referenced but not defined."""
4
5# (c) 2014-2016 Valentin Rothberg <[email protected]>
6# (c) 2014 Stefan Hengelein <[email protected]>
7#
8# Licensed under the terms of the GNU GPL License version 2
9
10
11import argparse
12import difflib
13import os
14import re
15import signal
16import subprocess
17import sys
18from multiprocessing import Pool, cpu_count
19
20
21# regex expressions
22OPERATORS = r"&|\(|\)|\||\!"
23SYMBOL = r"(?:\w*[A-Z0-9]\w*){2,}"
24DEF = r"^\s*(?:menu){,1}config\s+(" + SYMBOL + r")\s*"
25EXPR = r"(?:" + OPERATORS + r"|\s|" + SYMBOL + r")+"
26DEFAULT = r"default\s+.*?(?:if\s.+){,1}"
27STMT = r"^\s*(?:if|select|depends\s+on|(?:" + DEFAULT + r"))\s+" + EXPR
28SOURCE_SYMBOL = r"(?:\W|\b)+[D]{,1}CONFIG_(" + SYMBOL + r")"
29
30# regex objects
31REGEX_FILE_KCONFIG = re.compile(r".*Kconfig[\.\w+\-]*$")
32REGEX_SYMBOL = re.compile(r'(?!\B)' + SYMBOL + r'(?!\B)')
33REGEX_SOURCE_SYMBOL = re.compile(SOURCE_SYMBOL)
34REGEX_KCONFIG_DEF = re.compile(DEF)
35REGEX_KCONFIG_EXPR = re.compile(EXPR)
36REGEX_KCONFIG_STMT = re.compile(STMT)
37REGEX_KCONFIG_HELP = re.compile(r"^\s+(help|---help---)\s*$")
38REGEX_FILTER_SYMBOLS = 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 = "Run this tool to detect Kconfig symbols that are referenced but " \
46            "not defined in Kconfig.  If no option is specified, "             \
47            "checkkconfigsymbols defaults to check your current tree.  "       \
48            "Please note that specifying commits will 'git reset --hard\' "    \
49            "your current tree!  You may save uncommitted changes to avoid "   \
50            "losing data."
51
52    parser = argparse.ArgumentParser(description=usage)
53
54    parser.add_argument('-c', '--commit', dest='commit', action='store',
55                        default="",
56                        help="check if the specified commit (hash) introduces "
57                             "undefined Kconfig symbols")
58
59    parser.add_argument('-d', '--diff', dest='diff', action='store',
60                        default="",
61                        help="diff undefined symbols between two commits "
62                             "(e.g., -d commmit1..commit2)")
63
64    parser.add_argument('-f', '--find', dest='find', action='store_true',
65                        default=False,
66                        help="find and show commits that may cause symbols to be "
67                             "missing (required to run with --diff)")
68
69    parser.add_argument('-i', '--ignore', dest='ignore', action='store',
70                        default="",
71                        help="ignore files matching this Python regex "
72                             "(e.g., -i '.*defconfig')")
73
74    parser.add_argument('-s', '--sim', dest='sim', action='store', default="",
75                        help="print a list of max. 10 string-similar symbols")
76
77    parser.add_argument('--force', dest='force', action='store_true',
78                        default=False,
79                        help="reset current Git tree even when it's dirty")
80
81    parser.add_argument('--no-color', dest='color', action='store_false',
82                        default=True,
83                        help="don't print colored output (default when not "
84                             "outputting to a terminal)")
85
86    args = parser.parse_args()
87
88    if args.commit and args.diff:
89        sys.exit("Please specify only one option at once.")
90
91    if args.diff and not re.match(r"^[\w\-\.]+\.\.[\w\-\.]+$", args.diff):
92        sys.exit("Please specify valid input in the following format: "
93                 "\'commit1..commit2\'")
94
95    if args.commit or args.diff:
96        if not args.force and tree_is_dirty():
97            sys.exit("The current Git tree is dirty (see 'git status').  "
98                     "Running this script may\ndelete important data since it "
99                     "calls 'git reset --hard' for some performance\nreasons. "
100                     " Please run this script in a clean Git tree or pass "
101                     "'--force' if you\nwant to ignore this warning and "
102                     "continue.")
103
104    if args.commit:
105        args.find = False
106
107    if args.ignore:
108        try:
109            re.match(args.ignore, "this/is/just/a/test.c")
110        except:
111            sys.exit("Please specify a valid Python regex.")
112
113    return args
114
115
116def main():
117    """Main function of this module."""
118    args = parse_options()
119
120    global COLOR
121    COLOR = args.color and sys.stdout.isatty()
122
123    if args.sim and not args.commit and not args.diff:
124        sims = find_sims(args.sim, args.ignore)
125        if sims:
126            print("%s: %s" % (yel("Similar symbols"), ', '.join(sims)))
127        else:
128            print("%s: no similar symbols found" % yel("Similar symbols"))
129        sys.exit(0)
130
131    # dictionary of (un)defined symbols
132    defined = {}
133    undefined = {}
134
135    if args.commit or args.diff:
136        head = get_head()
137
138        # get commit range
139        commit_a = None
140        commit_b = None
141        if args.commit:
142            commit_a = args.commit + "~"
143            commit_b = args.commit
144        elif args.diff:
145            split = args.diff.split("..")
146            commit_a = split[0]
147            commit_b = split[1]
148            undefined_a = {}
149            undefined_b = {}
150
151        # get undefined items before the commit
152        execute("git reset --hard %s" % commit_a)
153        undefined_a, _ = check_symbols(args.ignore)
154
155        # get undefined items for the commit
156        execute("git reset --hard %s" % commit_b)
157        undefined_b, defined = check_symbols(args.ignore)
158
159        # report cases that are present for the commit but not before
160        for symbol in sorted(undefined_b):
161            # symbol has not been undefined before
162            if symbol not in undefined_a:
163                files = sorted(undefined_b.get(symbol))
164                undefined[symbol] = files
165            # check if there are new files that reference the undefined symbol
166            else:
167                files = sorted(undefined_b.get(symbol) -
168                               undefined_a.get(symbol))
169                if files:
170                    undefined[symbol] = files
171
172        # reset to head
173        execute("git reset --hard %s" % head)
174
175    # default to check the entire tree
176    else:
177        undefined, defined = check_symbols(args.ignore)
178
179    # now print the output
180    for symbol in sorted(undefined):
181        print(red(symbol))
182
183        files = sorted(undefined.get(symbol))
184        print("%s: %s" % (yel("Referencing files"), ", ".join(files)))
185
186        sims = find_sims(symbol, args.ignore, defined)
187        sims_out = yel("Similar symbols")
188        if sims:
189            print("%s: %s" % (sims_out, ', '.join(sims)))
190        else:
191            print("%s: %s" % (sims_out, "no similar symbols found"))
192
193        if args.find:
194            print("%s:" % yel("Commits changing symbol"))
195            commits = find_commits(symbol, args.diff)
196            if commits:
197                for commit in commits:
198                    commit = commit.split(" ", 1)
199                    print("\t- %s (\"%s\")" % (yel(commit[0]), commit[1]))
200            else:
201                print("\t- no commit found")
202        print()  # new line
203
204
205def yel(string):
206    """
207    Color %string yellow.
208    """
209    return "\033[33m%s\033[0m" % string if COLOR else string
210
211
212def red(string):
213    """
214    Color %string red.
215    """
216    return "\033[31m%s\033[0m" % string if COLOR else string
217
218
219def execute(cmd):
220    """Execute %cmd and return stdout.  Exit in case of error."""
221    try:
222        cmdlist = cmd.split(" ")
223        stdout = subprocess.check_output(cmdlist, stderr=subprocess.STDOUT, shell=False)
224        stdout = stdout.decode(errors='replace')
225    except subprocess.CalledProcessError as fail:
226        exit("Failed to execute %s\n%s" % (cmd, fail))
227    return stdout
228
229
230def find_commits(symbol, diff):
231    """Find commits changing %symbol in the given range of %diff."""
232    commits = execute("git log --pretty=oneline --abbrev-commit -G %s %s"
233                      % (symbol, diff))
234    return [x for x in commits.split("\n") if x]
235
236
237def tree_is_dirty():
238    """Return true if the current working tree is dirty (i.e., if any file has
239    been added, deleted, modified, renamed or copied but not committed)."""
240    stdout = execute("git status --porcelain")
241    for line in stdout:
242        if re.findall(r"[URMADC]{1}", line[:2]):
243            return True
244    return False
245
246
247def get_head():
248    """Return commit hash of current HEAD."""
249    stdout = execute("git rev-parse HEAD")
250    return stdout.strip('\n')
251
252
253def partition(lst, size):
254    """Partition list @lst into eveni-sized lists of size @size."""
255    return [lst[i::size] for i in range(size)]
256
257
258def init_worker():
259    """Set signal handler to ignore SIGINT."""
260    signal.signal(signal.SIGINT, signal.SIG_IGN)
261
262
263def find_sims(symbol, ignore, defined=[]):
264    """Return a list of max. ten Kconfig symbols that are string-similar to
265    @symbol."""
266    if defined:
267        return sorted(difflib.get_close_matches(symbol, set(defined), 10))
268
269    pool = Pool(cpu_count(), init_worker)
270    kfiles = []
271    for gitfile in get_files():
272        if REGEX_FILE_KCONFIG.match(gitfile):
273            kfiles.append(gitfile)
274
275    arglist = []
276    for part in partition(kfiles, cpu_count()):
277        arglist.append((part, ignore))
278
279    for res in pool.map(parse_kconfig_files, arglist):
280        defined.extend(res[0])
281
282    return sorted(difflib.get_close_matches(symbol, set(defined), 10))
283
284
285def get_files():
286    """Return a list of all files in the current git directory."""
287    # use 'git ls-files' to get the worklist
288    stdout = execute("git ls-files")
289    if len(stdout) > 0 and stdout[-1] == "\n":
290        stdout = stdout[:-1]
291
292    files = []
293    for gitfile in stdout.rsplit("\n"):
294        if ".git" in gitfile or "ChangeLog" in gitfile or      \
295                ".log" in gitfile or os.path.isdir(gitfile) or \
296                gitfile.startswith("tools/"):
297            continue
298        files.append(gitfile)
299    return files
300
301
302def check_symbols(ignore):
303    """Find undefined Kconfig symbols and return a dict with the symbol as key
304    and a list of referencing files as value.  Files matching %ignore are not
305    checked for undefined symbols."""
306    pool = Pool(cpu_count(), init_worker)
307    try:
308        return check_symbols_helper(pool, ignore)
309    except KeyboardInterrupt:
310        pool.terminate()
311        pool.join()
312        sys.exit(1)
313
314
315def check_symbols_helper(pool, ignore):
316    """Helper method for check_symbols().  Used to catch keyboard interrupts in
317    check_symbols() in order to properly terminate running worker processes."""
318    source_files = []
319    kconfig_files = []
320    defined_symbols = []
321    referenced_symbols = dict()  # {file: [symbols]}
322
323    for gitfile in get_files():
324        if REGEX_FILE_KCONFIG.match(gitfile):
325            kconfig_files.append(gitfile)
326        else:
327            if ignore and not re.match(ignore, gitfile):
328                continue
329            # add source files that do not match the ignore pattern
330            source_files.append(gitfile)
331
332    # parse source files
333    arglist = partition(source_files, cpu_count())
334    for res in pool.map(parse_source_files, arglist):
335        referenced_symbols.update(res)
336
337    # parse kconfig files
338    arglist = []
339    for part in partition(kconfig_files, cpu_count()):
340        arglist.append((part, ignore))
341    for res in pool.map(parse_kconfig_files, arglist):
342        defined_symbols.extend(res[0])
343        referenced_symbols.update(res[1])
344    defined_symbols = set(defined_symbols)
345
346    # inverse mapping of referenced_symbols to dict(symbol: [files])
347    inv_map = dict()
348    for _file, symbols in referenced_symbols.items():
349        for symbol in symbols:
350            inv_map[symbol] = inv_map.get(symbol, set())
351            inv_map[symbol].add(_file)
352    referenced_symbols = inv_map
353
354    undefined = {}  # {symbol: [files]}
355    for symbol in sorted(referenced_symbols):
356        # filter some false positives
357        if symbol == "FOO" or symbol == "BAR" or \
358                symbol == "FOO_BAR" or symbol == "XXX":
359            continue
360        if symbol not in defined_symbols:
361            if symbol.endswith("_MODULE"):
362                # avoid false positives for kernel modules
363                if symbol[:-len("_MODULE")] in defined_symbols:
364                    continue
365            undefined[symbol] = referenced_symbols.get(symbol)
366    return undefined, defined_symbols
367
368
369def parse_source_files(source_files):
370    """Parse each source file in @source_files and return dictionary with source
371    files as keys and lists of references Kconfig symbols as values."""
372    referenced_symbols = dict()
373    for sfile in source_files:
374        referenced_symbols[sfile] = parse_source_file(sfile)
375    return referenced_symbols
376
377
378def parse_source_file(sfile):
379    """Parse @sfile and return a list of referenced Kconfig symbols."""
380    lines = []
381    references = []
382
383    if not os.path.exists(sfile):
384        return references
385
386    with open(sfile, "r", encoding='utf-8', errors='replace') as stream:
387        lines = stream.readlines()
388
389    for line in lines:
390        if "CONFIG_" not in line:
391            continue
392        symbols = REGEX_SOURCE_SYMBOL.findall(line)
393        for symbol in symbols:
394            if not REGEX_FILTER_SYMBOLS.search(symbol):
395                continue
396            references.append(symbol)
397
398    return references
399
400
401def get_symbols_in_line(line):
402    """Return mentioned Kconfig symbols in @line."""
403    return REGEX_SYMBOL.findall(line)
404
405
406def parse_kconfig_files(args):
407    """Parse kconfig files and return tuple of defined and references Kconfig
408    symbols.  Note, @args is a tuple of a list of files and the @ignore
409    pattern."""
410    kconfig_files = args[0]
411    ignore = args[1]
412    defined_symbols = []
413    referenced_symbols = dict()
414
415    for kfile in kconfig_files:
416        defined, references = parse_kconfig_file(kfile)
417        defined_symbols.extend(defined)
418        if ignore and re.match(ignore, kfile):
419            # do not collect references for files that match the ignore pattern
420            continue
421        referenced_symbols[kfile] = references
422    return (defined_symbols, referenced_symbols)
423
424
425def parse_kconfig_file(kfile):
426    """Parse @kfile and update symbol definitions and references."""
427    lines = []
428    defined = []
429    references = []
430    skip = False
431
432    if not os.path.exists(kfile):
433        return defined, references
434
435    with open(kfile, "r", encoding='utf-8', errors='replace') as stream:
436        lines = stream.readlines()
437
438    for i in range(len(lines)):
439        line = lines[i]
440        line = line.strip('\n')
441        line = line.split("#")[0]  # ignore comments
442
443        if REGEX_KCONFIG_DEF.match(line):
444            symbol_def = REGEX_KCONFIG_DEF.findall(line)
445            defined.append(symbol_def[0])
446            skip = False
447        elif REGEX_KCONFIG_HELP.match(line):
448            skip = True
449        elif skip:
450            # ignore content of help messages
451            pass
452        elif REGEX_KCONFIG_STMT.match(line):
453            line = REGEX_QUOTES.sub("", line)
454            symbols = get_symbols_in_line(line)
455            # multi-line statements
456            while line.endswith("\\"):
457                i += 1
458                line = lines[i]
459                line = line.strip('\n')
460                symbols.extend(get_symbols_in_line(line))
461            for symbol in set(symbols):
462                if REGEX_NUMERIC.match(symbol):
463                    # ignore numeric values
464                    continue
465                references.append(symbol)
466
467    return defined, references
468
469
470if __name__ == "__main__":
471    main()
472