summaryrefslogtreecommitdiff
path: root/bin/symbols-check.py
blob: 7daf603c5f9ab682de69bf705c2e450481659012 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
#!/usr/bin/env python3

import argparse
import os
import platform
import subprocess

# This list contains symbols that _might_ be exported for some platforms
PLATFORM_SYMBOLS = [
    '__bss_end__',
    '__bss_start__',
    '__bss_start',
    '__cxa_guard_abort',
    '__cxa_guard_acquire',
    '__cxa_guard_release',
    '__cxa_allocate_dependent_exception',
    '__cxa_allocate_exception',
    '__cxa_begin_catch',
    '__cxa_call_unexpected',
    '__cxa_current_exception_type',
    '__cxa_current_primary_exception',
    '__cxa_decrement_exception_refcount',
    '__cxa_deleted_virtual',
    '__cxa_demangle',
    '__cxa_end_catch',
    '__cxa_free_dependent_exception',
    '__cxa_free_exception',
    '__cxa_get_exception_ptr',
    '__cxa_get_globals',
    '__cxa_get_globals_fast',
    '__cxa_increment_exception_refcount',
    '__cxa_new_handler',
    '__cxa_pure_virtual',
    '__cxa_rethrow',
    '__cxa_rethrow_primary_exception',
    '__cxa_terminate_handler',
    '__cxa_throw',
    '__cxa_uncaught_exception',
    '__cxa_uncaught_exceptions',
    '__cxa_unexpected_handler',
    '__dynamic_cast',
    '__emutls_get_address',
    '__gxx_personality_v0',
    '__end__',
    '__odr_asan._glapi_Context',
    '__odr_asan._glapi_Dispatch',
    '_bss_end__',
    '_edata',
    '_end',
    '_fini',
    '_init',
    '_fbss',
    '_fdata',
    '_ftext',
]

def get_symbols_nm(nm, lib):
    '''
    List all the (non platform-specific) symbols exported by the library
    using `nm`
    '''
    symbols = []
    platform_name = platform.system()
    output = subprocess.check_output([nm, '-gP', lib],
                                     stderr=open(os.devnull, 'w')).decode("ascii")
    for line in output.splitlines():
        fields = line.split()
        if len(fields) == 2 or fields[1] == 'U':
            continue
        symbol_name = fields[0]
        if platform_name == 'Linux' or platform_name == 'GNU' or platform_name.startswith('GNU/'):
            if symbol_name in PLATFORM_SYMBOLS:
                continue
        elif platform_name == 'Darwin':
            assert symbol_name[0] == '_'
            symbol_name = symbol_name[1:]
        symbols.append(symbol_name)
    return symbols


def get_symbols_dumpbin(dumpbin, lib):
    '''
    List all the (non platform-specific) symbols exported by the library
    using `dumpbin`
    '''
    symbols = []
    output = subprocess.check_output([dumpbin, '/exports', lib],
                                     stderr=open(os.devnull, 'w')).decode("ascii")
    for line in output.splitlines():
        fields = line.split()
        # The lines with the symbols are made of at least 4 columns; see details below
        if len(fields) < 4:
            continue
        try:
            # Making sure the first 3 columns are a dec counter, a hex counter
            # and a hex address
            _ = int(fields[0], 10)
            _ = int(fields[1], 16)
            _ = int(fields[2], 16)
        except ValueError:
            continue
        symbol_name = fields[3]
        # De-mangle symbols
        if symbol_name[0] == '_' and '@' in symbol_name:
            symbol_name = symbol_name[1:].split('@')[0]
        symbols.append(symbol_name)
    return symbols


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--symbols-file',
                        action='store',
                        required=True,
                        help='path to file containing symbols')
    parser.add_argument('--lib',
                        action='store',
                        required=True,
                        help='path to library')
    parser.add_argument('--nm',
                        action='store',
                        help='path to binary (or name in $PATH)')
    parser.add_argument('--dumpbin',
                        action='store',
                        help='path to binary (or name in $PATH)')
    parser.add_argument('--ignore-symbol',
                        action='append',
                        help='do not process this symbol')
    args = parser.parse_args()

    try:
        if platform.system() == 'Windows':
            if not args.dumpbin:
                parser.error('--dumpbin is mandatory')
            lib_symbols = get_symbols_dumpbin(args.dumpbin, args.lib)
        else:
            if not args.nm:
                parser.error('--nm is mandatory')
            lib_symbols = get_symbols_nm(args.nm, args.lib)
    except:
        # We can't run this test, but we haven't technically failed it either
        # Return the GNU "skip" error code
        exit(77)
    mandatory_symbols = []
    optional_symbols = []
    with open(args.symbols_file) as symbols_file:
        qualifier_optional = '(optional)'
        for line in symbols_file.readlines():

            # Strip comments
            line = line.split('#')[0]
            line = line.strip()
            if not line:
                continue

            # Line format:
            # [qualifier] symbol
            qualifier = None
            symbol = None

            fields = line.split()
            if len(fields) == 1:
                symbol = fields[0]
            elif len(fields) == 2:
                qualifier = fields[0]
                symbol = fields[1]
            else:
                print(args.symbols_file + ': invalid format: ' + line)
                exit(1)

            # The only supported qualifier is 'optional', which means the
            # symbol doesn't have to be exported by the library
            if qualifier and not qualifier == qualifier_optional:
                print(args.symbols_file + ': invalid qualifier: ' + qualifier)
                exit(1)

            if qualifier == qualifier_optional:
                optional_symbols.append(symbol)
            else:
                mandatory_symbols.append(symbol)

    unknown_symbols = []
    for symbol in lib_symbols:
        if symbol in mandatory_symbols:
            continue
        if symbol in optional_symbols:
            continue
        if args.ignore_symbol and symbol in args.ignore_symbol:
            continue
        if symbol[:2] == '_Z':
            # As ajax found out, the compiler intentionally exports symbols
            # that we explicitly asked it not to export, and we can't do
            # anything about it:
            # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36022#c4
            continue
        unknown_symbols.append(symbol)

    missing_symbols = [
        sym for sym in mandatory_symbols if sym not in lib_symbols
    ]

    for symbol in unknown_symbols:
        print(args.lib + ': unknown symbol exported: ' + symbol)

    for symbol in missing_symbols:
        print(args.lib + ': missing symbol: ' + symbol)

    if unknown_symbols or missing_symbols:
        exit(1)
    exit(0)


if __name__ == '__main__':
    main()