bin/symbols-check.py

   1 #!/usr/bin/env python
   2
   3 import argparse
   4 import subprocess
   5 import os
   6
   7 # This list contains symbols that _might_ be exported for some platforms
   8 PLATFORM_SYMBOLS = [
   9     '__bss_end__',
  10     '__bss_start__',
  11     '__bss_start',
  12     '__end__',
  13     '_bss_end__',
  14     '_edata',
  15     '_end',
  16     '_fini',
  17     '_init',
  18 ]
  19
  20
  21 def get_symbols(nm, lib):
  22     '''
  23     List all the (non platform-specific) symbols exported by the library
  24     '''
  25     symbols = []
  26     output = subprocess.check_output([nm, '--format=bsd', '-D', '--defined-only', lib],
  27                                      stderr=open(os.devnull, 'w')).decode("ascii")
  28     for line in output.splitlines():
  29         (_, _, symbol_name) = line.split()
  30         symbols.append(symbol_name)
  31     return symbols
  32
  33
  34 def main():
  35     parser = argparse.ArgumentParser()
  36     parser.add_argument('--symbols-file',
  37                         action='store',
  38                         required=True,
  39                         help='path to file containing symbols')
  40     parser.add_argument('--lib',
  41                         action='store',
  42                         required=True,
  43                         help='path to library')
  44     parser.add_argument('--nm',
  45                         action='store',
  46                         required=True,
  47                         help='path to binary (or name in $PATH)')
  48     args = parser.parse_args()
  49
  50     try:
  51         lib_symbols = get_symbols(args.nm, args.lib)
  52     except:
  53         # We can't run this test, but we haven't technically failed it either
  54         # Return the GNU "skip" error code
  55         exit(77)
  56     mandatory_symbols = []
  57     optional_symbols = []
  58     with open(args.symbols_file) as symbols_file:
  59         qualifier_optional = '(optional)'
  60         for line in symbols_file.readlines():
  61
  62             # Strip comments
  63             line = line.split('#')[0]
  64             line = line.strip()
  65             if not line:
  66                 continue
  67
  68             # Line format:
  69             # [qualifier] symbol
  70             qualifier = None
  71             symbol = None
  72
  73             fields = line.split()
  74             if len(fields) == 1:
  75                 symbol = fields[0]
  76             elif len(fields) == 2:
  77                 qualifier = fields[0]
  78                 symbol = fields[1]
  79             else:
  80                 print(args.symbols_file + ': invalid format: ' + line)
  81                 exit(1)
  82
  83             # The only supported qualifier is 'optional', which means the
  84             # symbol doesn't have to be exported by the library
  85             if qualifier and not qualifier == qualifier_optional:
  86                 print(args.symbols_file + ': invalid qualifier: ' + qualifier)
  87                 exit(1)
  88
  89             if qualifier == qualifier_optional:
  90                 optional_symbols.append(symbol)
  91             else:
  92                 mandatory_symbols.append(symbol)
  93
  94     unknown_symbols = []
  95     for symbol in lib_symbols:
  96         if symbol in mandatory_symbols:
  97             continue
  98         if symbol in optional_symbols:
  99             continue
 100         if symbol in PLATFORM_SYMBOLS:
 101             continue
 102         unknown_symbols.append(symbol)
 103
 104     missing_symbols = [
 105         sym for sym in mandatory_symbols if sym not in lib_symbols
 106     ]
 107
 108     for symbol in unknown_symbols:
 109         print(args.lib + ': unknown symbol exported: ' + symbol)
 110
 111     for symbol in missing_symbols:
 112         print(args.lib + ': missing symbol: ' + symbol)
 113
 114     if unknown_symbols or missing_symbols:
 115         exit(1)
 116     exit(0)
 117
 118
 119 if __name__ == '__main__':
 120     main()