Function CheckGlobalStatic

tools/cpplint.py:6260–6336

Check for unsafe global or static objects. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. linenum: The number of the line to check. error: The function to call with any errors found.

(filename, clean_lines, linenum, error)

def CheckGlobalStatic(filename, clean_lines, linenum, error):
    """Check for unsafe global or static objects.

    Args:
      filename: The name of the current file.
      clean_lines: A CleansedLines instance containing the file.
      linenum: The number of the line to check.
      error: The function to call with any errors found.
    """
    line = clean_lines.elided[linenum]

    # Match two lines at a time to support multiline declarations
    if linenum + 1 < clean_lines.NumLines() and not re.search(r"[;({]", line):
        line += clean_lines.elided[linenum + 1].strip()

    # Check for people declaring static/global STL strings at the top level.
    # This is dangerous because the C++ language does not guarantee that
    # globals with constructors are initialized before the first access, and
    # also because globals can be destroyed when some threads are still running.
    # TODO(google): Generalize this to also find static unique_ptr instances.
    # TODO(google): File bugs for clang-tidy to find these.
    match = re.match(
        r"((?:|static +)(?:|const +))(?::*std::)?string( +const)? +"
        r"([a-zA-Z0-9_:]+)\b(.*)",
        line,
    )

    # Remove false positives:
    # - String pointers (as opposed to values).
    #    string *pointer
    #    const string *pointer
    #    string const *pointer
    #    string *const pointer
    #
    # - Functions and template specializations.
    #    string Function<Type>(...
    #    string Class<Type>::Method(...
    #
    # - Operators.  These are matched separately because operator names
    #   cross non-word boundaries, and trying to match both operators
    #   and functions at the same time would decrease accuracy of
    #   matching identifiers.
    #    string Class::operator*()
    if (
        match
        and not re.search(r"\bstring\b(\s+const)?\s*[\*\&]\s*(const\s+)?\w", line)
        and not re.search(r"\boperator\W", line)
        and not re.match(r'\s*(<.*>)?(::[a-zA-Z0-9_]+)*\s*\(([^"]|$)', match.group(4))
    ):
        if re.search(r"\bconst\b", line):
            error(
                filename,
                linenum,
                "runtime/string",
                4,
                "For a static/global string constant, use a C style string instead:"
                f' "{match.group(1)}char{match.group(2) or ""} {match.group(3)}[]".',
            )