#!/usr/bin/env python
# Script checking that all symbols exported by libpython start with Py or _Py

import subprocess
import sys
import sysconfig


def get_exported_symbols():
 LIBRARY = sysconfig.get_config_var('LIBRARY')
 if not LIBRARY:
 raise Exception("failed to get LIBRARY")

 args = ('nm', '-p', LIBRARY)
 print("+ %s" % ' '.join(args))
 proc = subprocess.run(args, stdout=subprocess.PIPE, universal_newlines=True)
 if proc.returncode:
 sys.stdout.write(proc.stdout)
 sys.exit(proc.returncode)

 stdout = proc.stdout.rstrip()
 if not stdout:
 raise Exception("command output is empty")
 return stdout


def get_smelly_symbols(stdout):
 symbols = []
 ignored_symtypes = set()
 for line in stdout.splitlines():
 # Split line '0000000000001b80 D PyTextIOWrapper_Type'
 if not line:
 continue

 parts = line.split(maxsplit=2)
 if len(parts) < 3:
 continue

 symtype = parts[1].strip()
 # Ignore private symbols.
 #
 # If lowercase, the symbol is usually local; if uppercase, the symbol
 # is global (external). There are however a few lowercase symbols that
 # are shown for special global symbols ("u", "v" and "w").
 if symtype.islower() and symtype not in "uvw":
 ignored_symtypes.add(symtype)
 continue

 symbol = parts[-1]
 if symbol.startswith(('Py', '_Py')):
 continue
 symbol = '%s (type: %s)' % (symbol, symtype)
 symbols.append(symbol)

 if ignored_symtypes:
 print("Ignored symbol types: %s" % ', '.join(sorted(ignored_symtypes)))
 print()
 return symbols


def main():
 nm_output = get_exported_symbols()
 symbols = get_smelly_symbols(nm_output)

 if not symbols:
 print("OK: no smelly symbol found")
 sys.exit(0)

 symbols.sort()
 for symbol in symbols:
 print("Smelly symbol: %s" % symbol)
 print()
 print("ERROR: Found %s smelly symbols!" % len(symbols))
 sys.exit(1)


if __name__ == "__main__":
 main()