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Diffstat (limited to 'poky/meta/lib/oe/license.py')
| -rw-r--r-- | poky/meta/lib/oe/license.py | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/poky/meta/lib/oe/license.py b/poky/meta/lib/oe/license.py new file mode 100644 index 000000000..ca385d518 --- /dev/null +++ b/poky/meta/lib/oe/license.py @@ -0,0 +1,243 @@ +# vi:sts=4:sw=4:et +"""Code for parsing OpenEmbedded license strings""" + +import ast +import re +from fnmatch import fnmatchcase as fnmatch + +def license_ok(license, dont_want_licenses): + """ Return False if License exist in dont_want_licenses else True """ + for dwl in dont_want_licenses: + # If you want to exclude license named generically 'X', we + # surely want to exclude 'X+' as well. In consequence, we + # will exclude a trailing '+' character from LICENSE in + # case INCOMPATIBLE_LICENSE is not a 'X+' license. + lic = license + if not re.search('\+$', dwl): + lic = re.sub('\+', '', license) + if fnmatch(lic, dwl): + return False + return True + +class LicenseError(Exception): + pass + +class LicenseSyntaxError(LicenseError): + def __init__(self, licensestr, exc): + self.licensestr = licensestr + self.exc = exc + LicenseError.__init__(self) + + def __str__(self): + return "error in '%s': %s" % (self.licensestr, self.exc) + +class InvalidLicense(LicenseError): + def __init__(self, license): + self.license = license + LicenseError.__init__(self) + + def __str__(self): + return "invalid characters in license '%s'" % self.license + +license_operator_chars = '&|() ' +license_operator = re.compile('([' + license_operator_chars + '])') +license_pattern = re.compile('[a-zA-Z0-9.+_\-]+$') + +class LicenseVisitor(ast.NodeVisitor): + """Get elements based on OpenEmbedded license strings""" + def get_elements(self, licensestr): + new_elements = [] + elements = list([x for x in license_operator.split(licensestr) if x.strip()]) + for pos, element in enumerate(elements): + if license_pattern.match(element): + if pos > 0 and license_pattern.match(elements[pos-1]): + new_elements.append('&') + element = '"' + element + '"' + elif not license_operator.match(element): + raise InvalidLicense(element) + new_elements.append(element) + + return new_elements + + """Syntax tree visitor which can accept elements previously generated with + OpenEmbedded license string""" + def visit_elements(self, elements): + self.visit(ast.parse(' '.join(elements))) + + """Syntax tree visitor which can accept OpenEmbedded license strings""" + def visit_string(self, licensestr): + self.visit_elements(self.get_elements(licensestr)) + +class FlattenVisitor(LicenseVisitor): + """Flatten a license tree (parsed from a string) by selecting one of each + set of OR options, in the way the user specifies""" + def __init__(self, choose_licenses): + self.choose_licenses = choose_licenses + self.licenses = [] + LicenseVisitor.__init__(self) + + def visit_Str(self, node): + self.licenses.append(node.s) + + def visit_BinOp(self, node): + if isinstance(node.op, ast.BitOr): + left = FlattenVisitor(self.choose_licenses) + left.visit(node.left) + + right = FlattenVisitor(self.choose_licenses) + right.visit(node.right) + + selected = self.choose_licenses(left.licenses, right.licenses) + self.licenses.extend(selected) + else: + self.generic_visit(node) + +def flattened_licenses(licensestr, choose_licenses): + """Given a license string and choose_licenses function, return a flat list of licenses""" + flatten = FlattenVisitor(choose_licenses) + try: + flatten.visit_string(licensestr) + except SyntaxError as exc: + raise LicenseSyntaxError(licensestr, exc) + return flatten.licenses + +def is_included(licensestr, whitelist=None, blacklist=None): + """Given a license string and whitelist and blacklist, determine if the + license string matches the whitelist and does not match the blacklist. + + Returns a tuple holding the boolean state and a list of the applicable + licenses that were excluded if state is False, or the licenses that were + included if the state is True. + """ + + def include_license(license): + return any(fnmatch(license, pattern) for pattern in whitelist) + + def exclude_license(license): + return any(fnmatch(license, pattern) for pattern in blacklist) + + def choose_licenses(alpha, beta): + """Select the option in an OR which is the 'best' (has the most + included licenses and no excluded licenses).""" + # The factor 1000 below is arbitrary, just expected to be much larger + # that the number of licenses actually specified. That way the weight + # will be negative if the list of licenses contains an excluded license, + # but still gives a higher weight to the list with the most included + # licenses. + alpha_weight = (len(list(filter(include_license, alpha))) - + 1000 * (len(list(filter(exclude_license, alpha))) > 0)) + beta_weight = (len(list(filter(include_license, beta))) - + 1000 * (len(list(filter(exclude_license, beta))) > 0)) + if alpha_weight >= beta_weight: + return alpha + else: + return beta + + if not whitelist: + whitelist = ['*'] + + if not blacklist: + blacklist = [] + + licenses = flattened_licenses(licensestr, choose_licenses) + excluded = [lic for lic in licenses if exclude_license(lic)] + included = [lic for lic in licenses if include_license(lic)] + if excluded: + return False, excluded + else: + return True, included + +class ManifestVisitor(LicenseVisitor): + """Walk license tree (parsed from a string) removing the incompatible + licenses specified""" + def __init__(self, dont_want_licenses, canonical_license, d): + self._dont_want_licenses = dont_want_licenses + self._canonical_license = canonical_license + self._d = d + self._operators = [] + + self.licenses = [] + self.licensestr = '' + + LicenseVisitor.__init__(self) + + def visit(self, node): + if isinstance(node, ast.Str): + lic = node.s + + if license_ok(self._canonical_license(self._d, lic), + self._dont_want_licenses) == True: + if self._operators: + ops = [] + for op in self._operators: + if op == '[': + ops.append(op) + elif op == ']': + ops.append(op) + else: + if not ops: + ops.append(op) + elif ops[-1] in ['[', ']']: + ops.append(op) + else: + ops[-1] = op + + for op in ops: + if op == '[' or op == ']': + self.licensestr += op + elif self.licenses: + self.licensestr += ' ' + op + ' ' + + self._operators = [] + + self.licensestr += lic + self.licenses.append(lic) + elif isinstance(node, ast.BitAnd): + self._operators.append("&") + elif isinstance(node, ast.BitOr): + self._operators.append("|") + elif isinstance(node, ast.List): + self._operators.append("[") + elif isinstance(node, ast.Load): + self.licensestr += "]" + + self.generic_visit(node) + +def manifest_licenses(licensestr, dont_want_licenses, canonical_license, d): + """Given a license string and dont_want_licenses list, + return license string filtered and a list of licenses""" + manifest = ManifestVisitor(dont_want_licenses, canonical_license, d) + + try: + elements = manifest.get_elements(licensestr) + + # Replace '()' to '[]' for handle in ast as List and Load types. + elements = ['[' if e == '(' else e for e in elements] + elements = [']' if e == ')' else e for e in elements] + + manifest.visit_elements(elements) + except SyntaxError as exc: + raise LicenseSyntaxError(licensestr, exc) + + # Replace '[]' to '()' for output correct license. + manifest.licensestr = manifest.licensestr.replace('[', '(').replace(']', ')') + + return (manifest.licensestr, manifest.licenses) + +class ListVisitor(LicenseVisitor): + """Record all different licenses found in the license string""" + def __init__(self): + self.licenses = set() + + def visit_Str(self, node): + self.licenses.add(node.s) + +def list_licenses(licensestr): + """Simply get a list of all licenses mentioned in a license string. + Binary operators are not applied or taken into account in any way""" + visitor = ListVisitor() + try: + visitor.visit_string(licensestr) + except SyntaxError as exc: + raise LicenseSyntaxError(licensestr, exc) + return visitor.licenses |