diff options
Diffstat (limited to 'kconfiglib.py')
| -rw-r--r-- | kconfiglib.py | 89 |
1 files changed, 85 insertions, 4 deletions
diff --git a/kconfiglib.py b/kconfiglib.py index 271f533..8b798b4 100644 --- a/kconfiglib.py +++ b/kconfiglib.py @@ -585,6 +585,20 @@ class Kconfig(object): KconfigError on syntax errors. Note that Kconfig files are not the same as .config files (which store configuration symbol values). + If KCONFIG_STRICT is set in the environment (to any value), warnings + will be generated for all references to undefined symbols within + Kconfig files. The reason this isn't the default is that some projects + (e.g. the Linux kernel) use multiple Kconfig trees (one per + architecture) with many shared Kconfig files, leading to some safe + references to undefined symbols. + + KCONFIG_STRICT relies on literal hex values being prefixed with 0x/0X. + They are indistinguishable from references to undefined symbols + otherwise. + + KCONFIG_STRICT might enable other warnings that depend on there being + just a single Kconfig tree in the future. + filename (default: "Kconfig"): The Kconfig file to load. For the Linux kernel, you'll want "Kconfig" from the top-level directory, as environment variables will make sure @@ -641,10 +655,7 @@ class Kconfig(object): self.srctree = os.environ.get("srctree", "") self.config_prefix = os.environ.get("CONFIG_", "CONFIG_") - # Regular expressions for parsing .config files, with the match() - # method assigned directly as a small optimization (microscopic in this - # case, but it's consistent with the other regexes) - + # Regular expressions for parsing .config files self._set_match = _re_match(self.config_prefix + r"([^=]+)=(.*)") self._unset_match = \ _re_match(r"# {}([^ ]+) is not set".format(self.config_prefix)) @@ -771,6 +782,9 @@ class Kconfig(object): for choice in self.choices: _check_choice_sanity(choice) + if os.environ.get("KCONFIG_STRICT") == "y": + self._check_undefined_syms() + # Build Symbol._dependents for all symbols and choices self._build_dep() @@ -2980,6 +2994,50 @@ class Kconfig(object): return open(filename, "rU" if mode == "r" else mode) if _IS_PY2 else \ open(filename, mode, encoding=self._encoding) + def _check_undefined_syms(self): + # Prints warnings for all references to undefined symbols within the + # Kconfig files + + for sym in (self.syms.viewvalues() if _IS_PY2 else self.syms.values()): + # - sym.nodes empty means the symbol is undefined (has no + # definition locations) + # + # - Due to Kconfig internals, numbers show up as undefined Kconfig + # symbols, but shouldn't be flagged + # + # - The MODULES symbol always exists + if not sym.nodes and not _is_num(sym.name) and \ + sym.name != "MODULES": + + self._warn_undefined_sym(sym) + + def _warn_undefined_sym(self, sym): + # _check_undefined_syms() helper. Generates a warning that lists the + # locations where the undefined symbol 'sym' is referenced, including + # the referencing menu nodes in Kconfig format. + + referencing_nodes = [] + + def find_refs(node): + while node: + if sym in node.referenced: + referencing_nodes.append(node) + + if node.list: + find_refs(node.list) + + node = node.next + + find_refs(self.top_node) + + msg = "undefined symbol {}:".format(sym.name) + + for node in referencing_nodes: + msg += "\n\n- Referenced at {}:{}:\n\n{}" \ + .format(node.filename, node.linenr, node) + + self._warn(msg) + def _warn(self, msg, filename=None, linenr=None): # For printing general warnings @@ -5065,6 +5123,29 @@ def _strcmp(s1, s2): return (s1 > s2) - (s1 < s2) +def _is_num(s): + # Returns True if the string 's' looks like a number. + # + # Internally, all operands in Kconfig are symbols, only undefined symbols + # (which numbers usually are) get their name as their value. + # + # Only hex numbers that start with 0x/0X are classified as numbers. + # Otherwise, symbols whose names happen to contain only the letters A-F + # would trigger false positives. + + try: + int(s) + except ValueError: + if s.startswith(("0x", "0X")): + return False + + try: + int(s, 16) + except ValueError: + return False + + return True + def _sym_to_num(sym): # expr_value() helper for converting a symbol to a number. Raises # ValueError for symbols that can't be converted. |