cppcheck/addons/misra_9.py
Georgiy Komarov 79f59d8f39
misra: Fixed crash with struct fields with unknown types on 9.x rules (#3305)
This fixes the crash on with struct fields containing unknown types
reported on the forum:
https://sourceforge.net/p/cppcheck/discussion/general/thread/d64551cc55/#5f0f

The suggested patch doesn't handle the cases when there are struct
fields with arrays containing unknown types. So the addon will not
generate warnings in these cases. The problem is that Cppcheck doesn't
generate valueType-pointer information for unknown types in the dump
file. When adding this in symboldatabase.cpp, MISRA addon will generate
a lot of false positives because we depend on the null value of
valueType.

So I suppose it better to left this as is, to don't break the addon for
such rare cases.
2021-06-24 08:29:27 +02:00

511 lines
19 KiB
Python

# Holds information about an array, struct or union's element definition.
class ElementDef:
def __init__(self, elementType, name, valueType, dimensions = None):
self.elementType = elementType # 'array', 'record' or 'value'
self.name = str(name)
self.valueType = valueType
self.children = []
self.dimensions = dimensions
self.parent = None
self.isDesignated = False
self.isPositional = False
self.numInits = 0
self.childIndex = -1
self.flexibleToken = None
self.isFlexible = False
self.structureViolationToken = None
def __repr__(self):
inits = ""
if self.isPositional:
inits += 'P'
if self.isDesignated:
inits += 'D'
if not (self.isPositional or self.isDesignated) and self.numInits == 0:
inits += '_'
if self.numInits > 1:
inits += str(self.numInits)
attrs = ["childIndex", "elementType", "valueType"]
return "{}({}, {}, {})".format(
"ED",
self.getLongName(),
inits,
", ".join(("{}={}".format(a, repr(getattr(self, a))) for a in attrs))
)
@property
def isArray(self):
return self.elementType == 'array'
@property
def isRecord(self):
return self.elementType == 'record'
@property
def isValue(self):
return self.elementType == 'value'
def getLongName(self):
return self.parent.getLongName() + "." + self.name if self.parent else self.name
def getInitDump(self):
t = []
if self.isPositional:
t.append('P')
if self.isDesignated:
t.append('D')
if self.numInits == 0:
t.append('_')
if self.numInits > 1:
t.append(str(self.numInits))
myDump = "".join(t)
if len(self.children):
childDumps = []
for c in self.children:
childDumps.append(c.getInitDump())
if self.structureViolationToken is not None:
myDump += "!"
myDump += "{ " + ", ".join(childDumps) + " }"
return myDump
def addChild(self, child):
self.children.append(child)
child.parent = self
def getNextChild(self):
self.childIndex += 1
return self.getChildByIndex(self.childIndex)
def getChildByIndex(self, index):
if self.isFlexible:
while len(self.children) <= index:
createChild(self, self.flexibleToken, len(self.children))
return self.children[index] if 0 <= index < len(self.children) else None
def getChildByName(self, name):
for c in self.children:
if c.name == name:
return c
return None
def getNextValueElement(self, root):
current = self
while current != root:
if not current.parent:
return None
# Get next index of parent
i = current.parent.children.index(current) + 1
# Next index of parent exists
if i < len(current.parent.children):
current = current.parent.children[i]
return current.getFirstValueElement()
# Next index of parent doesn't exist. Move up
current = current.parent
return None
def getFirstValueElement(self):
current = self
# Move to first child as long as children exists
next_child = current.getChildByIndex(0)
while next_child:
current = next_child
next_child = current.getChildByIndex(0)
return current
def getLastValueElement(self):
current = self
# Move to last child as long as children exists
while len(current.children) > 0:
current = current.children[-1]
return current
def getChildByValueElement(self, ed):
potentialChild = ed
while potentialChild and potentialChild not in self.children:
potentialChild = potentialChild.parent
return self.children[self.children.index(potentialChild)] if potentialChild else None
def getEffectiveLevel(self):
if self.parent and self.parent.elementType == "array":
return self.parent.getEffectiveLevel() + 1
else:
return 0
def setInitialized(self, designated=False, positional=False):
if designated:
self.isDesignated = True
if positional or not designated:
self.isPositional = True
self.numInits += 1
def initializeChildren(self):
for child in self.children:
child.setInitialized(positional=True)
child.initializeChildren()
def unset(self):
self.isDesignated = False
self.isPositional = False
# Unset is always recursive
for child in self.children:
child.unset()
def markStuctureViolation(self, token):
if self.name == '->':
self.children[0].markStuctureViolation(token)
elif not self.structureViolationToken:
self.structureViolationToken = token
def markAsFlexibleArray(self, token):
self.flexibleToken = token
self.isFlexible = True
def markAsCurrent(self):
if self.parent:
if self.name == '<-':
self.parent.childIndex = self.parent.children.index(self.children[0])
else:
self.parent.childIndex = self.parent.children.index(self)
self.parent.markAsCurrent()
def isAllChildrenSet(self):
myself = len(self.children) == 0 and (self.isDesignated or self.isPositional)
mychildren = len(self.children) > 0 and all([child.isAllChildrenSet() for child in self.children])
return myself or mychildren
def isAllSet(self):
return all([child.isPositional or child.isDesignated for child in self.children])
def isOnlyDesignated(self):
return all([not child.isPositional for child in self.children])
def isMisra92Compliant(self):
return self.structureViolationToken is None and all([child.isMisra92Compliant() for child in self.children])
def isMisra93Compliant(self):
if self.elementType == 'array':
result = self.isAllChildrenSet() or \
((self.isAllSet() or
self.isOnlyDesignated()) and
all([not (child.isDesignated or child.isPositional) or child.isMisra93Compliant() for child in self.children]))
return result
elif self.elementType == 'record':
result = all([child.isMisra93Compliant() for child in self.children])
return result
else:
return True
def isMisra94Compliant(self):
return self.numInits <= 1 and all([child.isMisra94Compliant() for child in self.children])
def isMisra95Compliant(self):
return not self.isFlexible or all([not child.isDesignated for child in self.children])
# Parses the initializers and update the ElementDefs status accordingly
class InitializerParser:
def __init__(self):
self.token = None
self.root = None
self.ed = None
self.rootStack = []
def parseInitializer(self, root, token):
self.root = root
self.token = token
dummyRoot = ElementDef('array', '->', self.root.valueType)
dummyRoot.children = [self.root]
self.rootStack = []
self.root = dummyRoot
self.ed = self.root.getFirstValueElement()
isFirstElement = False
isDesignated = False
while self.token:
if self.token.str == ',':
self.token = self.token.astOperand1
isFirstElement = False
# Designated initializer ( [2]=... or .name=... )
elif self.token.isAssignmentOp and not self.token.valueType:
self.popFromStackIfExitElement()
self.ed = getElementByDesignator(self.root, self.token.astOperand1)
if self.ed:
# Update root
self.pushToRootStackAndMarkAsDesignated()
# Make sure ed points to valueElement
self.ed = self.ed.getFirstValueElement()
self.token = self.token.astOperand2
isFirstElement = False
isDesignated = True
elif self.token.str == '{':
nextChild = self.root.getNextChild() if self.root is not None else None
if nextChild:
if nextChild.isArray or nextChild.isRecord:
nextChild.unset()
nextChild.setInitialized(isDesignated)
self.ed = nextChild.getFirstValueElement()
isDesignated = False
elif nextChild.valueType is None:
# No type information available - unable to check structure - assume correct initialization
nextChild.setInitialized(isDesignated)
self.unwindAndContinue()
continue
elif self.token.astOperand1:
# Create dummy nextChild to represent excess levels in initializer
dummyRoot = ElementDef('array', '<-', self.root.valueType)
dummyRoot.parent = self.root
dummyRoot.childIndex = 0
dummyRoot.children = [nextChild]
nextChild.parent = dummyRoot
self.root.markStuctureViolation(self.token)
# Fake dummy as nextChild (of current root)
nextChild = dummyRoot
if self.token.astOperand1:
self.root = nextChild
self.token = self.token.astOperand1
isFirstElement = True
else:
if self.root:
# {}
if self.root.name == '<-':
self.root.parent.markStuctureViolation(self.token)
else:
self.root.markStuctureViolation(self.token)
self.ed = None
self.unwindAndContinue()
else:
if self.ed and self.ed.isValue:
if not isDesignated and len(self.rootStack) > 0 and self.rootStack[-1][1] == self.root:
self.rootStack[-1][0].markStuctureViolation(self.token)
if isFirstElement and self.token.str == '0' and self.token.next.str == '}':
# Zero initializer causes recursive initialization
self.root.initializeChildren()
elif self.token.isString and self.ed.valueType and self.ed.valueType.pointer > 0:
if self.ed.valueType.pointer - self.ed.getEffectiveLevel() == 1:
if self.ed.parent != self.root:
self.root.markStuctureViolation(self.token)
self.ed.setInitialized(isDesignated)
elif self.ed.valueType.pointer == self.ed.getEffectiveLevel():
if(self.root.name != '->' and self.ed.parent.parent != self.root) or (self.root.name == '->' and self.root.children[0] != self.ed.parent):
self.root.markStuctureViolation(self.token)
else:
self.ed.parent.setInitialized(isDesignated)
self.ed.parent.initializeChildren()
else:
if self.ed.parent != self.root:
# Check if token is correct value type for self.root.children[?]
child = self.root.getChildByValueElement(self.ed)
if child.elementType != 'record' or self.token.valueType.type != 'record' or child.valueType.typeScope != self.token.valueType.typeScope:
self.root.markStuctureViolation(self.token)
self.ed.setInitialized(isDesignated)
# Mark all elements up to root with positional or designated
# (for complex designators, or missing structure)
parent = self.ed.parent
while parent and parent != self.root:
parent.isDesignated = isDesignated if isDesignated and not parent.isPositional else parent.isDesignated
parent.isPositional = not isDesignated if not isDesignated and not parent.isDesignated else parent.isPositional
parent = parent.parent
isDesignated = False
self.unwindAndContinue()
def pushToRootStackAndMarkAsDesignated(self):
new = self.ed.parent
if new != self.root:
# Mark all elements up to self.root root as designated
parent = new
while parent and parent != self.root:
parent.isDesignated = True
parent = parent.parent
self.rootStack.append((self.root, new))
new.markAsCurrent()
new.childIndex = new.children.index(self.ed) - 1
self.root = new
def popFromStackIfExitElement(self):
if len(self.rootStack) > 0 and self.rootStack[-1][1] == self.root:
old = self.rootStack.pop()[0]
old.markAsCurrent()
self.root = old
def unwindAndContinue(self):
while self.token:
if self.token.astParent.astOperand1 == self.token and self.token.astParent.astOperand2:
if self.ed:
self.ed.markAsCurrent()
self.ed = self.ed.getNextValueElement(self.root)
self.token = self.token.astParent.astOperand2
break
else:
self.token = self.token.astParent
if self.token.str == '{':
if self.root:
self.ed = self.root.getLastValueElement()
self.ed.markAsCurrent()
# Cleanup if root is dummy node representing excess levels in initializer
if self.root.name == '<-':
self.root.children[0].parent = self.root.parent
self.root = self.root.parent
if self.token.astParent is None:
self.token = None
break
def misra_9_x(self, data, rule, rawTokens = None):
parser = InitializerParser()
for variable in data.variables:
if not variable.nameToken:
continue
nameToken = variable.nameToken
# Check if declaration and initialization is
# split into two separate statements in ast.
if nameToken.next and nameToken.next.isSplittedVarDeclEq:
nameToken = nameToken.next.next
# Find declarations with initializer assignment
eq = nameToken
while not eq.isAssignmentOp and eq.astParent:
eq = eq.astParent
# We are only looking for initializers
if not eq.isAssignmentOp or eq.astOperand2.isName:
continue
if variable.isArray or variable.isClass:
ed = getElementDef(nameToken, rawTokens)
# No need to check non-arrays if valueType is missing,
# since we can't say anything useful about the structure
# without it.
if ed.valueType is None and not variable.isArray:
continue
parser.parseInitializer(ed, eq.astOperand2)
# print(rule, nameToken.str + '=', ed.getInitDump())
if rule == 902 and not ed.isMisra92Compliant():
self.reportError(nameToken, 9, 2)
if rule == 903 and not ed.isMisra93Compliant():
self.reportError(nameToken, 9, 3)
if rule == 904 and not ed.isMisra94Compliant():
self.reportError(nameToken, 9, 4)
if rule == 905 and not ed.isMisra95Compliant():
self.reportError(nameToken, 9, 5)
def getElementDef(nameToken, rawTokens = None):
if nameToken.variable.isArray:
ed = ElementDef("array", nameToken.str, nameToken.valueType)
createArrayChildrenDefs(ed, nameToken.astParent, rawTokens)
elif nameToken.variable.isClass:
ed = ElementDef("record", nameToken.str, nameToken.valueType)
createRecordChildrenDefs(ed)
else:
ed = ElementDef("value", nameToken.str, nameToken.valueType)
return ed
def createArrayChildrenDefs(ed, token, rawTokens = None):
if token.str == '[':
if rawTokens is not None:
foundToken = next((rawToken for rawToken in rawTokens
if rawToken.file == token.file
and rawToken.linenr == token.linenr
and rawToken.column == token.column
), None)
if foundToken and foundToken.next and foundToken.next.str == ']':
ed.markAsFlexibleArray(token)
if (token.astOperand2 is not None) and (token.astOperand2.getKnownIntValue() is not None):
for i in range(token.astOperand2.getKnownIntValue()):
createChild(ed, token, i)
else:
ed.markAsFlexibleArray(token)
def createChild(ed, token, name):
if token.astParent and token.astParent.str == '[':
child = ElementDef("array", name, ed.valueType)
createArrayChildrenDefs(child, token.astParent)
else:
if ed.valueType and ed.valueType.type == "record":
child = ElementDef("record", name, ed.valueType)
createRecordChildrenDefs(child)
else:
child = ElementDef("value", name, ed.valueType)
ed.addChild(child)
def createRecordChildrenDefs(ed):
valueType = ed.valueType
if not valueType or not valueType.typeScope:
return
for variable in valueType.typeScope.varlist:
child = getElementDef(variable.nameToken)
ed.addChild(child)
def getElementByDesignator(ed, token):
if not token.str in [ '.', '[' ]:
return None
while token.str in [ '.', '[' ]:
token = token.astOperand1
while ed and not token.isAssignmentOp:
token = token.astParent
if token.str == '[':
if not ed.isArray:
ed.markStuctureViolation(token)
chIndex = -1
if token.astOperand2 is not None:
chIndex = token.astOperand2.getKnownIntValue()
elif token.astOperand1 is not None:
chIndex = token.astOperand1.getKnownIntValue()
ed = ed.getChildByIndex(chIndex) if chIndex is not None else None
elif token.str == '.':
if not ed.isRecord:
ed.markStuctureViolation(token)
name = ""
if token.astOperand2 is not None:
name = token.astOperand2.str
elif token.astOperand1 is not None:
name = token.astOperand1.str
ed = ed.getChildByName(name)
return ed