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     lib_symbols = get_symbols(args.nm, args.lib)
  51     mandatory_symbols = []
  52     optional_symbols = []
  53     with open(args.symbols_file) as symbols_file:
  54         qualifier_optional = '(optional)'
  55         for line in symbols_file.readlines():
  56
  57             # Strip comments
  58             line = line.split('#')[0]
  59             line = line.strip()
  60             if not line:
  61                 continue
  62
  63             # Line format:
  64             # [qualifier] symbol
  65             qualifier = None
  66             symbol = None
  67
  68             fields = line.split()
  69             if len(fields) == 1:
  70                 symbol = fields[0]
  71             elif len(fields) == 2:
  72                 qualifier = fields[0]
  73                 symbol = fields[1]
  74             else:
  75                 print(args.symbols_file + ': invalid format: ' + line)
  76                 exit(1)
  77
  78             # The only supported qualifier is 'optional', which means the
  79             # symbol doesn't have to be exported by the library
  80             if qualifier and not qualifier == qualifier_optional:
  81                 print(args.symbols_file + ': invalid qualifier: ' + qualifier)
  82                 exit(1)
  83
  84             if qualifier == qualifier_optional:
  85                 optional_symbols.append(symbol)
  86             else:
  87                 mandatory_symbols.append(symbol)
  88
  89     unknown_symbols = []
  90     for symbol in lib_symbols:
  91         if symbol in mandatory_symbols:
  92             continue
  93         if symbol in optional_symbols:
  94             continue
  95         if symbol in PLATFORM_SYMBOLS:
  96             continue
  97         unknown_symbols.append(symbol)
  98
  99     missing_symbols = [
 100         sym for sym in mandatory_symbols if sym not in lib_symbols
 101     ]
 102
 103     for symbol in unknown_symbols:
 104         print(args.lib + ': unknown symbol exported: ' + symbol)
 105
 106     for symbol in missing_symbols:
 107         print(args.lib + ': missing symbol: ' + symbol)
 108
 109     if unknown_symbols or missing_symbols:
 110         exit(1)
 111     exit(0)
 112
 113
 114 if __name__ == '__main__':
 115     main()