1#!/usr/bin/env python
2# SPDX-License-Identifier: GPL-2.0
3# Copyright Thomas Gleixner <tglx@linutronix.de>
4
5from argparse import ArgumentParser
6from ply import lex, yacc
7import locale
8import traceback
9import sys
10import git
11import re
12import os
13
14class ParserException(Exception):
15    def __init__(self, tok, txt):
16        self.tok = tok
17        self.txt = txt
18
19class SPDXException(Exception):
20    def __init__(self, el, txt):
21        self.el = el
22        self.txt = txt
23
24class SPDXdata(object):
25    def __init__(self):
26        self.license_files = 0
27        self.exception_files = 0
28        self.licenses = [ ]
29        self.exceptions = { }
30
31# Read the spdx data from the LICENSES directory
32def read_spdxdata(repo):
33
34    # The subdirectories of LICENSES in the kernel source
35    license_dirs = [ "preferred", "other", "exceptions" ]
36    lictree = repo.head.commit.tree['LICENSES']
37
38    spdx = SPDXdata()
39
40    for d in license_dirs:
41        for el in lictree[d].traverse():
42            if not os.path.isfile(el.path):
43                continue
44
45            exception = None
46            for l in open(el.path).readlines():
47                if l.startswith('Valid-License-Identifier:'):
48                    lid = l.split(':')[1].strip().upper()
49                    if lid in spdx.licenses:
50                        raise SPDXException(el, 'Duplicate License Identifier: %s' %lid)
51                    else:
52                        spdx.licenses.append(lid)
53
54                elif l.startswith('SPDX-Exception-Identifier:'):
55                    exception = l.split(':')[1].strip().upper()
56                    spdx.exceptions[exception] = []
57
58                elif l.startswith('SPDX-Licenses:'):
59                    for lic in l.split(':')[1].upper().strip().replace(' ', '').replace('\t', '').split(','):
60                        if not lic in spdx.licenses:
61                            raise SPDXException(None, 'Exception %s missing license %s' %(ex, lic))
62                        spdx.exceptions[exception].append(lic)
63
64                elif l.startswith("License-Text:"):
65                    if exception:
66                        if not len(spdx.exceptions[exception]):
67                            raise SPDXException(el, 'Exception %s is missing SPDX-Licenses' %excid)
68                        spdx.exception_files += 1
69                    else:
70                        spdx.license_files += 1
71                    break
72    return spdx
73
74class id_parser(object):
75
76    reserved = [ 'AND', 'OR', 'WITH' ]
77    tokens = [ 'LPAR', 'RPAR', 'ID', 'EXC' ] + reserved
78
79    precedence = ( ('nonassoc', 'AND', 'OR'), )
80
81    t_ignore = ' \t'
82
83    def __init__(self, spdx):
84        self.spdx = spdx
85        self.lasttok = None
86        self.lastid = None
87        self.lexer = lex.lex(module = self, reflags = re.UNICODE)
88        # Initialize the parser. No debug file and no parser rules stored on disk
89        # The rules are small enough to be generated on the fly
90        self.parser = yacc.yacc(module = self, write_tables = False, debug = False)
91        self.lines_checked = 0
92        self.checked = 0
93        self.spdx_valid = 0
94        self.spdx_errors = 0
95        self.curline = 0
96        self.deepest = 0
97
98    # Validate License and Exception IDs
99    def validate(self, tok):
100        id = tok.value.upper()
101        if tok.type == 'ID':
102            if not id in self.spdx.licenses:
103                raise ParserException(tok, 'Invalid License ID')
104            self.lastid = id
105        elif tok.type == 'EXC':
106            if id not in self.spdx.exceptions:
107                raise ParserException(tok, 'Invalid Exception ID')
108            if self.lastid not in self.spdx.exceptions[id]:
109                raise ParserException(tok, 'Exception not valid for license %s' %self.lastid)
110            self.lastid = None
111        elif tok.type != 'WITH':
112            self.lastid = None
113
114    # Lexer functions
115    def t_RPAR(self, tok):
116        r'\)'
117        self.lasttok = tok.type
118        return tok
119
120    def t_LPAR(self, tok):
121        r'\('
122        self.lasttok = tok.type
123        return tok
124
125    def t_ID(self, tok):
126        r'[A-Za-z.0-9\-+]+'
127
128        if self.lasttok == 'EXC':
129            print(tok)
130            raise ParserException(tok, 'Missing parentheses')
131
132        tok.value = tok.value.strip()
133        val = tok.value.upper()
134
135        if val in self.reserved:
136            tok.type = val
137        elif self.lasttok == 'WITH':
138            tok.type = 'EXC'
139
140        self.lasttok = tok.type
141        self.validate(tok)
142        return tok
143
144    def t_error(self, tok):
145        raise ParserException(tok, 'Invalid token')
146
147    def p_expr(self, p):
148        '''expr : ID
149                | ID WITH EXC
150                | expr AND expr
151                | expr OR expr
152                | LPAR expr RPAR'''
153        pass
154
155    def p_error(self, p):
156        if not p:
157            raise ParserException(None, 'Unfinished license expression')
158        else:
159            raise ParserException(p, 'Syntax error')
160
161    def parse(self, expr):
162        self.lasttok = None
163        self.lastid = None
164        self.parser.parse(expr, lexer = self.lexer)
165
166    def parse_lines(self, fd, maxlines, fname):
167        self.checked += 1
168        self.curline = 0
169        try:
170            for line in fd:
171                line = line.decode(locale.getpreferredencoding(False), errors='ignore')
172                self.curline += 1
173                if self.curline > maxlines:
174                    break
175                self.lines_checked += 1
176                if line.find("SPDX-License-Identifier:") < 0:
177                    continue
178                expr = line.split(':')[1].replace('*/', '').strip()
179                self.parse(expr)
180                self.spdx_valid += 1
181                #
182                # Should we check for more SPDX ids in the same file and
183                # complain if there are any?
184                #
185                break
186
187        except ParserException as pe:
188            if pe.tok:
189                col = line.find(expr) + pe.tok.lexpos
190                tok = pe.tok.value
191                sys.stdout.write('%s: %d:%d %s: %s\n' %(fname, self.curline, col, pe.txt, tok))
192            else:
193                sys.stdout.write('%s: %d:0 %s\n' %(fname, self.curline, col, pe.txt))
194            self.spdx_errors += 1
195
196def scan_git_tree(tree):
197    for el in tree.traverse():
198        # Exclude stuff which would make pointless noise
199        # FIXME: Put this somewhere more sensible
200        if el.path.startswith("LICENSES"):
201            continue
202        if el.path.find("license-rules.rst") >= 0:
203            continue
204        if not os.path.isfile(el.path):
205            continue
206        with open(el.path, 'rb') as fd:
207            parser.parse_lines(fd, args.maxlines, el.path)
208
209def scan_git_subtree(tree, path):
210    for p in path.strip('/').split('/'):
211        tree = tree[p]
212    scan_git_tree(tree)
213
214if __name__ == '__main__':
215
216    ap = ArgumentParser(description='SPDX expression checker')
217    ap.add_argument('path', nargs='*', help='Check path or file. If not given full git tree scan. For stdin use "-"')
218    ap.add_argument('-m', '--maxlines', type=int, default=15,
219                    help='Maximum number of lines to scan in a file. Default 15')
220    ap.add_argument('-v', '--verbose', action='store_true', help='Verbose statistics output')
221    args = ap.parse_args()
222
223    # Sanity check path arguments
224    if '-' in args.path and len(args.path) > 1:
225        sys.stderr.write('stdin input "-" must be the only path argument\n')
226        sys.exit(1)
227
228    try:
229        # Use git to get the valid license expressions
230        repo = git.Repo(os.getcwd())
231        assert not repo.bare
232
233        # Initialize SPDX data
234        spdx = read_spdxdata(repo)
235
236        # Initilize the parser
237        parser = id_parser(spdx)
238
239    except SPDXException as se:
240        if se.el:
241            sys.stderr.write('%s: %s\n' %(se.el.path, se.txt))
242        else:
243            sys.stderr.write('%s\n' %se.txt)
244        sys.exit(1)
245
246    except Exception as ex:
247        sys.stderr.write('FAIL: %s\n' %ex)
248        sys.stderr.write('%s\n' %traceback.format_exc())
249        sys.exit(1)
250
251    try:
252        if len(args.path) and args.path[0] == '-':
253            parser.parse_lines(sys.stdin, args.maxlines, '-')
254        else:
255            if args.path:
256                for p in args.path:
257                    if os.path.isfile(p):
258                        parser.parse_lines(open(p), args.maxlines, p)
259                    elif os.path.isdir(p):
260                        scan_git_subtree(repo.head.reference.commit.tree, p)
261                    else:
262                        sys.stderr.write('path %s does not exist\n' %p)
263                        sys.exit(1)
264            else:
265                # Full git tree scan
266                scan_git_tree(repo.head.commit.tree)
267
268            if args.verbose:
269                sys.stderr.write('\n')
270                sys.stderr.write('License files:     %12d\n' %spdx.license_files)
271                sys.stderr.write('Exception files:   %12d\n' %spdx.exception_files)
272                sys.stderr.write('License IDs        %12d\n' %len(spdx.licenses))
273                sys.stderr.write('Exception IDs      %12d\n' %len(spdx.exceptions))
274                sys.stderr.write('\n')
275                sys.stderr.write('Files checked:     %12d\n' %parser.checked)
276                sys.stderr.write('Lines checked:     %12d\n' %parser.lines_checked)
277                sys.stderr.write('Files with SPDX:   %12d\n' %parser.spdx_valid)
278                sys.stderr.write('Files with errors: %12d\n' %parser.spdx_errors)
279
280            sys.exit(0)
281
282    except Exception as ex:
283        sys.stderr.write('FAIL: %s\n' %ex)
284        sys.stderr.write('%s\n' %traceback.format_exc())
285        sys.exit(1)
286