/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2009 Daniel Marjamäki and Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
//---------------------------------------------------------------------------
#include "checkclass.h"
#include "tokenize.h"
#include "token.h"
#include "errorlogger.h"
#include
#include
#include
#include
#include
//---------------------------------------------------------------------------
// Register CheckClass..
namespace
{
CheckClass instance;
}
//---------------------------------------------------------------------------
CheckClass::Var *CheckClass::getVarList(const Token *tok1, bool withClasses, bool isStruct)
{
// Get variable list..
Var *varlist = NULL;
unsigned int indentlevel = 0;
bool priv = !isStruct;
for (const Token *tok = tok1; tok; tok = tok->next())
{
if (!tok->next())
break;
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
if (indentlevel != 1)
continue;
if (tok->str() == "__published:")
{
priv = false;
for (; tok; tok = tok->next())
{
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
if (indentlevel == 1 && Token::Match(tok->next(), "private:|protected:|public:"))
break;
}
if (tok)
continue;
else
break;
}
// "private:" "public:" "protected:" etc
const bool b((tok->str()[0] != ':') && tok->str().find(":") != std::string::npos);
if (b)
priv = bool(tok->str() == "private:");
// Search for start of statement..
if (! Token::Match(tok, "[;{}]") && ! b)
continue;
// This is the start of a statement
const Token *next = tok->next();
std::string varname;
// If next token contains a ":".. it is not part of a variable declaration
if (next->str().find(":") != std::string::npos)
continue;
// Variable declarations that start with "static" shall be ignored..
if (next->str() == "static")
continue;
// Type definitions shall be ignored..
if (next->str() == "typedef")
continue;
// Is it a variable declaration?
if (Token::Match(next, "%type% %var% ;"))
{
if (withClasses)
varname = next->strAt(1);
else if (next->isStandardType())
varname = next->strAt(1);
else if (Token::findmatch(_tokenizer->tokens(), ("enum " + next->str()).c_str()))
varname = next->strAt(1);
}
// Pointer?
else if (Token::Match(next, "%type% * %var% ;"))
{
varname = next->strAt(2);
}
// Pointer?
else if (Token::Match(next, "%type% %type% * %var% ;"))
{
varname = next->strAt(3);
}
// Array?
else if (Token::Match(next, "%type% %var% [") && next->next()->str() != "operator")
{
if (Token::findmatch(_tokenizer->tokens(), ("class " + next->str()).c_str()))
continue;
varname = next->strAt(1);
}
// Pointer array?
else if (Token::Match(next, "%type% * %var% ["))
{
varname = next->strAt(2);
}
// std::string..
else if (withClasses && Token::Match(next, "std :: string %var% ;"))
{
varname = next->strAt(3);
}
// Container..
else if (withClasses && Token::Match(next, "std :: %type% <"))
{
while (next && next->str() != ">")
next = next->next();
if (Token::Match(next, "> %var% ;"))
varname = next->strAt(1);
}
// If the varname was set in one of the two if-block above, create a entry for this variable..
if (!varname.empty() && varname != "operator")
{
Var *var = new Var(varname, false, priv, varlist);
varlist = var;
}
}
return varlist;
}
//---------------------------------------------------------------------------
void CheckClass::initVar(Var *varlist, const std::string &varname)
{
for (Var *var = varlist; var; var = var->next)
{
if (var->name == varname)
{
var->init = true;
return;
}
}
}
//---------------------------------------------------------------------------
void CheckClass::initializeVarList(const Token *tok1, const Token *ftok, Var *varlist, const std::string &classname, std::list &callstack, bool isStruct)
{
bool Assign = false;
unsigned int indentlevel = 0;
for (; ftok; ftok = ftok->next())
{
if (!ftok->next())
break;
// Class constructor.. initializing variables like this
// clKalle::clKalle() : var(value) { }
if (indentlevel == 0)
{
if (Assign && Token::Match(ftok, "%var% ("))
{
initVar(varlist, ftok->strAt(0));
}
Assign |= (ftok->str() == ":");
}
if (ftok->str() == "{")
{
++indentlevel;
Assign = false;
}
else if (ftok->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
if (indentlevel < 1)
continue;
// Variable getting value from stream?
if (Token::Match(ftok, ">> %var%"))
{
initVar(varlist, ftok->strAt(1));
}
// Before a new statement there is "[{};)=]" or "else"
if (! Token::Match(ftok, "[{};)=]") && ftok->str() != "else")
continue;
// Using the operator= function to initialize all variables..
if (Token::simpleMatch(ftok->next(), "* this = "))
{
for (Var *var = varlist; var; var = var->next)
var->init = true;
break;
}
if (!Token::Match(ftok->next(), "%var%") &&
!Token::Match(ftok->next(), "this . %var%") &&
!Token::Match(ftok->next(), "* %var% =") &&
!Token::Match(ftok->next(), "( * this ) . %var%"))
continue;
// Goto the first token in this statement..
ftok = ftok->next();
// Skip "( * this )"
if (Token::simpleMatch(ftok, "( * this ) ."))
{
ftok = ftok->tokAt(5);
}
// Skip "this->"
if (Token::simpleMatch(ftok, "this ."))
ftok = ftok->tokAt(2);
// Skip "classname :: "
if (Token::Match(ftok, "%var% ::"))
ftok = ftok->tokAt(2);
// Clearing all variables..
if (Token::simpleMatch(ftok, "memset ( this ,"))
{
for (Var *var = varlist; var; var = var->next)
var->init = true;
break;
}
// Clearing array..
else if (Token::Match(ftok, "memset ( %var% ,"))
{
initVar(varlist, ftok->strAt(2));
ftok = ftok->next()->link();
continue;
}
// Calling member function?
else if (Token::Match(ftok, "%var% ("))
{
// No recursive calls!
if (std::find(callstack.begin(), callstack.end(), ftok->str()) == callstack.end())
{
callstack.push_back(ftok->str());
int i = 0;
const Token *ftok2 = _tokenizer->findClassFunction(tok1, classname, ftok->strAt(0), i, isStruct);
if (ftok2)
{
initializeVarList(tok1, ftok2, varlist, classname, callstack, isStruct);
}
else // there is a called member function, but it is not defined where we can find it, so we assume it initializes everything
{
// check if the function is part of this class..
const Token *tok = Token::findmatch(_tokenizer->tokens(), (std::string("class ") + classname + " {").c_str());
for (tok = tok ? tok->tokAt(3) : 0; tok; tok = tok->next())
{
if (tok->str() == "{")
{
tok = tok->link();
if (!tok)
break;
}
else if (tok->str() == "}")
{
break;
}
else if (tok->str() == ftok->str() || tok->str() == "friend")
{
tok = 0;
break;
}
}
// bail out..
if (!tok)
{
for (Var *var = varlist; var; var = var->next)
var->init = true;
break;
}
// the function is external and it's neither friend nor inherited virtual function.
// assume all variables that are passed to it are initialized..
unsigned int indentlevel = 0;
for (tok = ftok->tokAt(2); tok; tok = tok->next())
{
if (tok->str() == "(")
++indentlevel;
else if (tok->str() == ")")
{
if (indentlevel == 0)
break;
--indentlevel;
}
if (tok->isName())
{
initVar(varlist, tok->strAt(0));
}
}
continue;
}
}
}
// Assignment of member variable?
else if (Token::Match(ftok, "%var% ="))
{
initVar(varlist, ftok->strAt(0));
}
// Assignment of array item of member variable?
else if (Token::Match(ftok, "%var% [ %any% ] ="))
{
initVar(varlist, ftok->strAt(0));
}
// Assignment of array item of member variable?
else if (Token::Match(ftok, "%var% [ %any% ] [ %any% ] ="))
{
initVar(varlist, ftok->strAt(0));
}
// Assignment of array item of member variable?
else if (Token::Match(ftok, "* %var% ="))
{
initVar(varlist, ftok->strAt(1));
}
// The functions 'clear' and 'Clear' are supposed to initialize variable.
if (Token::Match(ftok, "%var% . clear|Clear ("))
{
initVar(varlist, ftok->strAt(0));
}
}
}
//---------------------------------------------------------------------------
// ClassCheck: Check that all class constructors are ok.
//---------------------------------------------------------------------------
void CheckClass::constructors()
{
const char pattern_class[] = "class|struct %var% [{:]";
// Locate class
const Token *tok1 = Token::findmatch(_tokenizer->tokens(), pattern_class);
while (tok1)
{
const std::string className = tok1->strAt(1);
const Token *classNameToken = tok1->tokAt(1);
bool isStruct = tok1->str() == "struct";
/** @todo handling of private constructors should be improved */
bool hasPrivateConstructor = false;
{
int indentlevel = 0;
bool isPrivate = !isStruct;
for (const Token *tok = tok1; tok; tok = tok->next())
{
// Indentation
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
{
--indentlevel;
if (indentlevel <= 0)
break;
}
// Parse class contents (indentlevel == 1)..
if (indentlevel == 1)
{
// What section are we in.. private/non-private
if (tok->str() == "private:")
isPrivate = true;
else if (tok->str() == "protected:" || tok->str() == "public:")
isPrivate = false;
// Is there a private constructor?
else if (isPrivate && Token::simpleMatch(tok, (classNameToken->str() + " (").c_str()))
{
hasPrivateConstructor = true;
break;
}
}
}
}
if (hasPrivateConstructor && !_settings->_showAll)
{
/** @todo Handle private constructors. Right now to avoid
* false positives we just bail out */
tok1 = Token::findmatch(tok1->next(), pattern_class);
continue;
}
// Are there a class constructor?
std::string tempPattern = "%any% " + classNameToken->str() + " (";
const Token *constructor_token = Token::findmatch(tok1, tempPattern.c_str());
while (constructor_token && constructor_token->str() == "~")
constructor_token = Token::findmatch(constructor_token->next(), tempPattern.c_str());
// There are no constructor.
if (! constructor_token)
{
// If "--style" has been given, give a warning
if (_settings->_checkCodingStyle)
{
// Get class variables...
Var *varlist = getVarList(tok1, false, isStruct);
// If there is a private variable, there should be a constructor..
for (const Var *var = varlist; var; var = var->next)
{
if (var->priv)
{
noConstructorError(tok1, classNameToken->str(), isStruct);
break;
}
}
// Delete the varlist..
while (varlist)
{
Var *nextvar = varlist->next;
delete varlist;
varlist = nextvar;
}
}
tok1 = Token::findmatch(tok1->next(), pattern_class);
continue;
}
// Check constructors
checkConstructors(tok1, className, hasPrivateConstructor, isStruct);
// Check assignment operators
checkConstructors(tok1, "operator =", hasPrivateConstructor, isStruct);
tok1 = Token::findmatch(tok1->next(), pattern_class);
}
}
void CheckClass::checkConstructors(const Token *tok1, const std::string &funcname, bool hasPrivateConstructor, bool isStruct)
{
const std::string className = tok1->strAt(1);
// Check that all member variables are initialized..
bool withClasses = bool(_settings->_showAll && funcname == "operator =");
Var *varlist = getVarList(tok1, withClasses, isStruct);
int indentlevel = 0;
const Token *constructor_token = _tokenizer->findClassFunction(tok1, className, funcname, indentlevel, isStruct);
std::list callstack;
initializeVarList(tok1, constructor_token, varlist, className, callstack, isStruct);
while (constructor_token)
{
// Check if any variables are uninitialized
for (Var *var = varlist; var; var = var->next)
{
if (var->init)
continue;
// Is it a static member variable?
std::ostringstream pattern;
pattern << className << " :: " << var->name << " =";
if (Token::findmatch(_tokenizer->tokens(), pattern.str().c_str()))
continue;
// It's non-static and it's not initialized => error
if (Token::simpleMatch(constructor_token, "operator = (") ||
Token::simpleMatch(constructor_token->tokAt(2), "operator = ("))
{
const Token *operStart = 0;
if (Token::simpleMatch(constructor_token, "operator = ("))
operStart = constructor_token->tokAt(2);
else
operStart = constructor_token->tokAt(4);
bool classNameUsed = false;
for (const Token *operTok = operStart; operTok != operStart->link(); operTok = operTok->next())
{
if (operTok->str() == className)
{
classNameUsed = true;
break;
}
}
if (classNameUsed)
operatorEqVarError(constructor_token, className, var->name);
}
else
uninitVarError(constructor_token, className, var->name, hasPrivateConstructor);
}
for (Var *var = varlist; var; var = var->next)
var->init = false;
constructor_token = _tokenizer->findClassFunction(constructor_token->next(), className, funcname, indentlevel, isStruct);
callstack.clear();
initializeVarList(tok1, constructor_token, varlist, className, callstack, isStruct);
}
// Delete the varlist..
while (varlist)
{
Var *nextvar = varlist->next;
delete varlist;
varlist = nextvar;
}
}
//---------------------------------------------------------------------------
// ClassCheck: Unused private functions
//---------------------------------------------------------------------------
void CheckClass::privateFunctions()
{
// Locate some class
for (const Token *tok1 = Token::findmatch(_tokenizer->tokens(), "class|struct %var% {"); tok1; tok1 = Token::findmatch(tok1->next(), "class|struct %var% {"))
{
/** @todo check that the whole class implementation is seen */
// until the todo above is fixed we only check classes that are
// declared in the source file
if (tok1->fileIndex() != 0)
continue;
const std::string &classname = tok1->next()->str();
// Get private functions..
std::list FuncList;
FuncList.clear();
bool isStruct = tok1->str() == "struct";
bool priv = !isStruct;
unsigned int indent_level = 0;
for (const Token *tok = tok1; tok; tok = tok->next())
{
if (Token::Match(tok, "friend %var%"))
{
/** @todo Handle friend classes */
FuncList.clear();
break;
}
if (tok->str() == "{")
++indent_level;
else if (tok->str() == "}")
{
if (indent_level <= 1)
break;
--indent_level;
}
else if (indent_level != 1)
continue;
else if (tok->str() == "private:")
priv = true;
else if (tok->str() == "public:")
priv = false;
else if (tok->str() == "protected:")
priv = false;
else if (priv)
{
if (Token::Match(tok, "typedef %type% ("))
tok = tok->tokAt(2)->link();
else if (Token::Match(tok, "[:,] %var% ("))
tok = tok->tokAt(2)->link();
else if (Token::Match(tok, "%var% (") &&
!Token::simpleMatch(tok->next()->link(), ") (") &&
!Token::Match(tok, classname.c_str()))
{
FuncList.push_back(tok);
}
}
/** @todo embedded class have access to private functions */
if (tok->str() == "class")
{
FuncList.clear();
break;
}
}
// Check that all private functions are used..
bool HasFuncImpl = false;
bool inclass = false;
indent_level = 0;
for (const Token *ftok = _tokenizer->tokens(); ftok; ftok = ftok->next())
{
if (ftok->str() == "{")
++indent_level;
else if (ftok->str() == "}")
{
if (indent_level > 0)
--indent_level;
if (indent_level == 0)
inclass = false;
}
if (Token::Match(ftok, ("class " + classname + " :|{").c_str()))
{
indent_level = 0;
inclass = true;
}
// Check member class functions to see what functions are used..
if ((inclass && indent_level == 1 && Token::Match(ftok, ") const| {")) ||
(Token::Match(ftok, (classname + " :: ~| %var% (").c_str())))
{
while (ftok && ftok->str() != ")")
ftok = ftok->next();
if (!ftok)
break;
if (Token::Match(ftok, ") : %var% ("))
{
while (!Token::Match(ftok->next(), "[{};]"))
ftok = ftok->next();
}
if (!Token::Match(ftok, ") const| {"))
continue;
if (ftok->fileIndex() == 0)
HasFuncImpl = true;
// Parse function..
int indentlevel2 = 0;
for (const Token *tok2 = ftok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "{")
++indentlevel2;
else if (tok2->str() == "}")
{
--indentlevel2;
if (indentlevel2 < 1)
break;
}
else if (Token::Match(tok2, "%var% ("))
{
// Remove function from FuncList
std::list::iterator it = FuncList.begin();
while (it != FuncList.end())
{
if (tok2->str() == (*it)->str())
FuncList.erase(it++);
else
it++;
}
}
}
}
}
while (HasFuncImpl && !FuncList.empty())
{
// Final check; check if the function pointer is used somewhere..
const std::string _pattern("return|(|)|,|= " + FuncList.front()->str());
if (!Token::findmatch(_tokenizer->tokens(), _pattern.c_str()))
{
unusedPrivateFunctionError(FuncList.front(), classname, FuncList.front()->str());
}
FuncList.pop_front();
}
}
}
//---------------------------------------------------------------------------
// ClassCheck: Check that memset is not used on classes
//---------------------------------------------------------------------------
void CheckClass::noMemset()
{
// Locate all 'memset' tokens..
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
if (!Token::Match(tok, "memset|memcpy|memmove"))
continue;
std::string type;
if (Token::Match(tok, "memset ( %var% , %num% , sizeof ( %type% ) )"))
type = tok->strAt(8);
else if (Token::Match(tok, "memset ( & %var% , %num% , sizeof ( %type% ) )"))
type = tok->strAt(9);
else if (Token::Match(tok, "memset ( %var% , %num% , sizeof ( struct %type% ) )"))
type = tok->strAt(9);
else if (Token::Match(tok, "memset ( & %var% , %num% , sizeof ( struct %type% ) )"))
type = tok->strAt(10);
else if (Token::Match(tok, "%type% ( %var% , %var% , sizeof ( %type% ) )"))
type = tok->strAt(8);
// No type defined => The tokens didn't match
if (type.empty())
continue;
// Warn if type is a class or struct that contains any std::* variables
const std::string pattern2(std::string("struct|class ") + type + " {");
for (const Token *tstruct = Token::findmatch(_tokenizer->tokens(), pattern2.c_str()); tstruct; tstruct = tstruct->next())
{
if (tstruct->str() == "}")
break;
// struct with function? skip function body..
if (Token::simpleMatch(tstruct, ") {"))
{
tstruct = tstruct->next()->link();
if (!tstruct)
break;
}
// before a statement there must be either:
// * private:|protected:|public:
// * { } ;
if (Token::Match(tstruct, "[;{}]") ||
tstruct->str().find(":") != std::string::npos)
{
if (Token::Match(tstruct->next(), "std :: %type% %var% ;"))
memsetStructError(tok, tok->str(), tstruct->strAt(3));
else if (Token::Match(tstruct->next(), "std :: %type% < "))
{
// backup the type
const std::string typestr(tstruct->strAt(3));
// check if it's a pointer variable..
unsigned int level = 0;
while (0 != (tstruct = tstruct->next()))
{
if (tstruct->str() == "<")
++level;
else if (tstruct->str() == ">")
{
if (level <= 1)
break;
--level;
}
else if (tstruct->str() == "(")
tstruct = tstruct->link();
}
if (!tstruct)
break;
// found error => report
if (Token::Match(tstruct, "> %var% ;"))
memsetStructError(tok, tok->str(), typestr);
}
}
}
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// ClassCheck: "void operator=("
//---------------------------------------------------------------------------
void CheckClass::operatorEq()
{
const Token *tok2 = _tokenizer->tokens();
const Token *tok;
while ((tok = Token::findmatch(tok2, "void operator = (")))
{
const Token *tok1 = tok;
while (tok1 && !Token::Match(tok1, "class|struct %var%"))
{
if (tok1->str() == "public:")
{
operatorEqReturnError(tok);
break;
}
if (tok1->str() == "private:" || tok1->str() == "protected:")
break;
tok1 = tok1->previous();
}
if (tok1 && Token::Match(tok1, "struct %var%"))
operatorEqReturnError(tok);
tok2 = tok->next();
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// ClassCheck: "C& operator=(const C&) { ... return *this; }"
// operator= should return a reference to *this
//---------------------------------------------------------------------------
// match two lists of tokens
static bool nameMatch(const Token * tok1, const Token * tok2, int length)
{
for (int i = 0; i < length; i++)
{
if (tok1->tokAt(i) == 0 || tok2->tokAt(i) == 0)
return false;
if (tok1->tokAt(i)->str() != tok2->tokAt(i)->str())
return false;
}
return true;
}
// create a class name from a list of tokens
static void nameStr(const Token * name, int length, std::string & str)
{
for (int i = 0; i < length; i++)
{
if (i != 0)
str += " ";
str += name->tokAt(i)->str();
}
}
void CheckClass::operatorEqRetRefThis()
{
const Token *tok2 = _tokenizer->tokens();
const Token *tok;
while ((tok = Token::findmatch(tok2, "operator = (")))
{
const Token *tok1 = tok;
if (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::"))
{
// make sure this is an assignment operator
int nameLength = 1;
tok1 = tok1->tokAt(-2);
// check backwards for proper function signature
while (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::"))
{
tok1 = tok1->tokAt(-2);
nameLength += 2;
}
const Token *name = tok1;
std::string nameString;
nameStr(name, nameLength, nameString);
if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&")
{
// check class name
if (tok1->tokAt(-(1 + nameLength)) && nameMatch(name, tok1->tokAt(-(1 + nameLength)), nameLength))
{
// may take overloaded argument types so no need to check them
tok1 = tok->tokAt(2)->link();
if (tok1 && tok1->next() && tok1->next()->str() == "{")
{
const Token *last = tok1->next()->link();
for (tok1 = tok1->tokAt(2); tok1 && tok1 != last; tok1 = tok1->next())
{
// check for return of reference to this
if (tok1->str() == "return")
{
std::string cast("( " + name->str() + " & )");
if (Token::Match(tok1->next(), cast.c_str()))
tok1 = tok1->tokAt(4);
if (!(Token::Match(tok1->tokAt(1), "(| * this ;|=") ||
Token::Match(tok1->tokAt(1), "(| * this +=") ||
Token::Match(tok1->tokAt(1), "operator = (")))
operatorEqRetRefThisError(tok);
}
}
}
}
}
}
else
{
// make sure this is an assignment operator
tok1 = tok;
// check backwards for proper function signature
if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&")
{
const Token *name = 0;
bool isPublic = false;
while (tok1 && !Token::Match(tok1, "class|struct %var%"))
{
if (!isPublic)
{
if (tok1->str() == "public:")
isPublic = true;
}
tok1 = tok1->previous();
}
if (tok1 && Token::Match(tok1, "struct %var%"))
{
isPublic = true;
name = tok1->tokAt(1);
}
else if (tok1 && Token::Match(tok1, "class %var%"))
{
name = tok1->tokAt(1);
}
if (tok->tokAt(-2) && tok->tokAt(-2)->str() == name->str())
{
// may take overloaded argument types so no need to check them
tok1 = tok->tokAt(2)->link();
if (tok1 && tok1->next() && tok1->next()->str() == "{")
{
const Token *last = tok1->next()->link();
for (tok1 = tok1->tokAt(2); tok1 && tok1 != last; tok1 = tok1->next())
{
// check for return of reference to this
if (tok1->str() == "return")
{
std::string cast("( " + name->str() + " & )");
if (Token::Match(tok1->next(), cast.c_str()))
tok1 = tok1->tokAt(4);
if (!(Token::Match(tok1->tokAt(1), "(| * this ;|=") ||
Token::Match(tok1->tokAt(1), "(| * this +=") ||
Token::Match(tok1->tokAt(1), "operator = (")))
operatorEqRetRefThisError(tok);
}
}
}
}
}
}
tok2 = tok->next();
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// ClassCheck: "C& operator=(const C& rhs) { if (this == &rhs) ... }"
// operator= should check for assignment to self
//
// For simple classes, an assignment to self check is only a potential optimization.
//
// For classes that allocate dynamic memory, assignment to self can be a real error
// if it is deallocated and allocated again without being checked for.
//
// This check is not valid for classes with multiple inheritance because a
// class can have multiple addresses so there is no trivial way to check for
// assignment to self.
//---------------------------------------------------------------------------
static bool hasDeallocation(const Token * first, const Token * last)
{
// This function is called when no simple check was found for assignment
// to self. We are currently looking for a specific sequence of:
// deallocate member ; ... member = allocate
// This check is far from ideal because it can cause false negatives.
// Unfortunately, this is necessary to prevent false positives.
// This check needs to do careful analysis someday to get this
// correct with a high degree of certainty.
for (const Token * tok = first; tok && (tok != last); tok = tok->next())
{
// check for deallocating memory
if (Token::Match(tok, "{|;|, free ( %var%"))
{
const Token * var = tok->tokAt(3);
// we should probably check that var is a pointer in this class
const Token * tok1 = tok->tokAt(4);
while (tok1 && (tok1 != last))
{
if (Token::Match(tok1, "%var% ="))
{
if (tok1->str() == var->str())
return true;
}
tok1 = tok1->next();
}
}
else if (Token::Match(tok, "{|;|, delete [ ] %var%"))
{
const Token * var = tok->tokAt(4);
// we should probably check that var is a pointer in this class
const Token * tok1 = tok->tokAt(5);
while (tok1 && (tok1 != last))
{
if (Token::Match(tok1, "%var% = new ["))
{
if (tok1->str() == var->str())
return true;
}
tok1 = tok1->next();
}
}
else if (Token::Match(tok, "{|;|, delete %var%"))
{
const Token * var = tok->tokAt(2);
// we should probably check that var is a pointer in this class
const Token * tok1 = tok->tokAt(3);
while (tok1 && (tok1 != last))
{
if (Token::Match(tok1, "%var% = new"))
{
if (tok1->str() == var->str())
return true;
}
tok1 = tok1->next();
}
}
}
return false;
}
static bool hasAssignSelf(const Token * first, const Token * last, const Token * rhs)
{
for (const Token * tok = first; tok && tok != last; tok = tok->next())
{
if (Token::Match(tok, "if ("))
{
const Token * tok1 = tok->tokAt(2);
const Token * tok2 = tok->tokAt(1)->link();
if (tok1 && tok2)
{
for (; tok1 && tok1 != tok2; tok1 = tok1->next())
{
if (Token::Match(tok1, "this ==|!= & %var%"))
{
if (tok1->tokAt(3)->str() == rhs->str())
return true;
}
else if (Token::Match(tok1, "& %var% ==|!= this"))
{
if (tok1->tokAt(1)->str() == rhs->str())
return true;
}
}
}
}
}
return false;
}
static bool hasMultipleInheritanceInline(const Token * tok)
{
while (tok && tok->str() != "{")
{
if (tok->str() == ",")
return true;
tok = tok->next();
}
return false;
}
static bool hasMultipleInheritanceGlobal(const Token * start, const std::string & name)
{
const Token *tok = start;
std::string pattern;
std::string className = name;
// check for nested classes
while (className.find("::") != std::string::npos)
{
std::string tempName;
// there is probably a better way to do this
while (className[0] != ' ')
{
tempName += className[0];
className.erase(0, 1);
}
className.erase(0, 4);
pattern = "class|struct " + tempName;
tok = Token::findmatch(tok, pattern.c_str());
}
pattern = "class|struct " + className;
tok = Token::findmatch(tok, pattern.c_str());
return hasMultipleInheritanceInline(tok);
}
void CheckClass::operatorEqToSelf()
{
const Token *tok2 = _tokenizer->tokens();
const Token *tok;
while ((tok = Token::findmatch(tok2, "operator = (")))
{
const Token *tok1 = tok;
// make sure this is an assignment operator
if (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::"))
{
int nameLength = 1;
tok1 = tok1->tokAt(-2);
// check backwards for proper function signature
while (tok1->tokAt(-2) && Token::Match(tok1->tokAt(-2), " %type% ::"))
{
tok1 = tok1->tokAt(-2);
nameLength += 2;
}
const Token *name = tok1;
std::string nameString;
nameStr(name, nameLength, nameString);
if (!hasMultipleInheritanceGlobal(_tokenizer->tokens(), nameString))
{
if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&")
{
// check returned class name
if (tok1->tokAt(-(1 + nameLength)) && nameMatch(name, tok1->tokAt(-(1 + nameLength)), nameLength))
{
// check forward for proper function signature
std::string pattern = "const " + nameString + " & %var% )";
if (Token::Match(tok->tokAt(3), pattern.c_str()))
{
const Token * rhs = tok->tokAt(5 + nameLength);
if (nameMatch(name, tok->tokAt(4), nameLength))
{
tok1 = tok->tokAt(2)->link();
if (tok1 && tok1->tokAt(1) && tok1->tokAt(1)->str() == "{" && tok1->tokAt(1)->link())
{
const Token *first = tok1->tokAt(1);
const Token *last = first->link();
if (!hasAssignSelf(first, last, rhs))
{
if (hasDeallocation(first, last))
operatorEqToSelfError(tok);
}
}
}
}
}
}
}
}
else
{
tok1 = tok;
// check backwards for proper function signature
if (tok1->tokAt(-1) && tok1->tokAt(-1)->str() == "&")
{
const Token *name = 0;
while (tok1 && !Token::Match(tok1, "class|struct %var%"))
tok1 = tok1->previous();
if (Token::Match(tok1, "struct|class %var%"))
name = tok1->tokAt(1);
if (!hasMultipleInheritanceInline(tok1))
{
if (Token::simpleMatch(tok->tokAt(-2), name->str().c_str()))
{
// check forward for proper function signature
if (Token::Match(tok->tokAt(3), "const %type% & %var% )"))
{
const Token * rhs = tok->tokAt(6);
if (tok->tokAt(4)->str() == name->str())
{
tok1 = tok->tokAt(2)->link();
if (tok1 && Token::simpleMatch(tok1->next(), "{"))
{
const Token *first = tok1->next();
const Token *last = first->link();
if (!hasAssignSelf(first, last, rhs))
{
if (hasDeallocation(first, last))
operatorEqToSelfError(tok);
}
}
}
}
}
}
}
}
tok2 = tok->next();
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// A destructor in a base class should be virtual
//---------------------------------------------------------------------------
void CheckClass::virtualDestructor()
{
const char pattern_classdecl[] = "class %var% : %var%";
const Token *derived = _tokenizer->tokens();
while ((derived = Token::findmatch(derived, pattern_classdecl)) != NULL)
{
// Check that the derived class has a non empty destructor..
{
std::ostringstream destructorPattern;
destructorPattern << "~ " << derived->strAt(1) << " ( ) {";
const Token *derived_destructor = Token::findmatch(_tokenizer->tokens(), destructorPattern.str().c_str());
// No destructor..
if (! derived_destructor)
{
derived = derived->next();
continue;
}
// Empty destructor..
if (Token::Match(derived_destructor, "~ %var% ( ) { }"))
{
derived = derived->next();
continue;
}
}
const Token *derivedClass = derived->tokAt(1);
// Iterate through each base class...
derived = derived->tokAt(3);
while (Token::Match(derived, "%var%"))
{
bool isPublic(derived->str() == "public");
// What kind of inheritance is it.. public|protected|private
if (Token::Match(derived, "public|protected|private"))
derived = derived->next();
// Name of base class..
const std::string baseName = derived->strAt(0);
// Update derived so it's ready for the next loop.
do
{
if (derived->str() == "{")
break;
if (derived->str() == ",")
{
derived = derived->next();
break;
}
derived = derived->next();
}
while (derived);
// If not public inheritance, skip checking of this base class..
if (! isPublic)
continue;
// Find the destructor declaration for the base class.
const Token *base = Token::findmatch(_tokenizer->tokens(), (std::string("%any% ~ ") + baseName + " (").c_str());
while (base && base->str() == "::")
base = Token::findmatch(base->next(), (std::string("%any% ~ ") + baseName + " (").c_str());
const Token *reverseTok = base;
while (Token::Match(base, "%var%") && base->str() != "virtual")
base = base->previous();
// Check that there is a destructor..
if (! base)
{
// Is the class declaration available?
base = Token::findmatch(_tokenizer->tokens(), (std::string("class ") + baseName + " {").c_str());
if (base)
{
virtualDestructorError(base, baseName, derivedClass->str());
}
continue;
}
// There is a destructor. Check that it's virtual..
else if (base->str() == "virtual")
continue;
// TODO: This is just a temporary fix, better solution is needed.
// Skip situations where base class has base classes of its own, because
// some of the base classes might have virtual destructor.
// Proper solution is to check all of the base classes. If base class is not
// found or if one of the base classes has virtual destructor, error should not
// be printed. See TODO test case "virtualDestructorInherited"
if (!Token::findmatch(_tokenizer->tokens(), (std::string("class ") + baseName + " {").c_str()))
continue;
// Make sure that the destructor is public (protected or private
// would not compile if inheritance is used in a way that would
// cause the bug we are trying to find here.)
int indent = 0;
while (reverseTok)
{
if (reverseTok->str() == "public:")
{
virtualDestructorError(base, baseName, derivedClass->str());
break;
}
else if (reverseTok->str() == "protected:" ||
reverseTok->str() == "private:")
{
// No bug, protected/private destructor is allowed
break;
}
else if (reverseTok->str() == "{")
{
indent++;
if (indent >= 1)
{
// We have found the start of the class without any sign
// of "public :" so we can assume that the destructor is not
// public and there is no bug in the code we are checking.
break;
}
}
else if (reverseTok->str() == "}")
indent--;
reverseTok = reverseTok->previous();
}
}
}
}
//---------------------------------------------------------------------------
void CheckClass::thisSubtractionError(const Token *tok)
{
reportError(tok, Severity::possibleStyle, "thisSubtraction", "Suspicious pointer subtraction");
}
void CheckClass::thisSubtraction()
{
const Token *tok = _tokenizer->tokens();
for (;;)
{
tok = Token::findmatch(tok, "this - %var%");
if (!tok)
break;
if (!Token::simpleMatch(tok->previous(), "*"))
thisSubtractionError(tok);
tok = tok->next();
}
}
//---------------------------------------------------------------------------
const Token * findParameter(const Token *var, const Token *start, const Token * end)
{
const Token * param = start->next();
for (; param && param != end; param = param->next())
{
if (param->varId()) // a function parameter
{
// check if the variable and the parameter name are the same
if (var->str() == param->str())
return param;
}
}
return 0;
}
struct NestInfo
{
std::string className;
const Token * classEnd;
int levelEnd;
};
// Can a function be const?
void CheckClass::checkConst()
{
if (!_settings->_checkCodingStyle)
return;
std::vector nestInfo;
int level = 0;
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
if (tok->str() == "{" && !nestInfo.empty())
level++;
else if (tok->str() == "}" && !nestInfo.empty())
{
level--;
if (level == nestInfo.back().levelEnd)
nestInfo.pop_back();
}
else if (Token::Match(tok, "class|struct %var% {"))
{
// get class name..
std::string classname(tok->strAt(1));
// goto initial {'
while (tok && tok->str() != "{")
tok = tok->next();
if (!tok)
break;
const Token *classEnd = tok->link();
NestInfo info;
info.className = classname;
info.classEnd = classEnd;
info.levelEnd = level++;
nestInfo.push_back(info);
// parse in this class definition to see if there are any simple getter functions
for (const Token *tok2 = tok->next(); tok2; tok2 = tok2->next())
{
if (tok2->str() == "{")
tok2 = tok2->link();
else if (tok2->str() == "}")
break;
// start of statement?
if (!Token::Match(tok2->previous(), "[;{}]"))
continue;
// skip private: public: etc
if (tok2->isName() && tok2->str().find(":") != std::string::npos)
tok2 = tok2->next();
// static functions can't be const
// virtual functions may be non-const for a reason
if (Token::Match(tok2, "static|virtual"))
continue;
// don't warn if type is LP..
if (tok2->str().compare(0, 2, "LP") == 0)
continue;
// member function?
if (Token::Match(tok2, "%type% %var% (") ||
Token::Match(tok2, "%type% %type% %var% (") ||
Token::Match(tok2, "const %type% &|* %var% (") ||
Token::Match(tok2, "const std :: %type% &|*| %var% (") ||
Token::Match(tok2, "%type% operator %any% ("))
{
// goto function name..
while (tok2->next()->str() != "(")
tok2 = tok2->next();
// get function name
const std::string functionName((tok2->isName() ? "" : "operator") + tok2->str());
// skip constructor
if (functionName == classname)
continue;
// goto the ')'
tok2 = tok2->next()->link();
if (!tok2)
break;
// is this a non-const function that is implemented inline?
if (Token::simpleMatch(tok2, ") {"))
{
const Token *paramEnd = tok2;
const Token *paramStart = tok2->link();
// if nothing non-const was found. write error..
if (checkConstFunc(paramStart, paramEnd))
{
for (int i = nestInfo.size() - 2; i >= 0; i--)
classname = std::string(nestInfo[i].className + "::" + classname);
checkConstError(tok2, classname, functionName);
}
}
else if (Token::simpleMatch(tok2, ") ;")) // not inline
{
for (int i = nestInfo.size() - 1; i >= 0; i--)
{
const Token *found = nestInfo[i].classEnd;
std::string pattern(functionName + " (");
int level = 0;
for (int j = nestInfo.size() - 1; j >= i; j--, level++)
pattern = std::string(nestInfo[j].className + " :: " + pattern);
while ((found = Token::findmatch(found->next(), pattern.c_str())))
{
const Token *paramStart = found->tokAt(1 + (2 * level));
const Token *paramEnd = paramStart->link();
if (!paramEnd)
break;
if (paramEnd->next()->str() != "{")
break;
if (sameFunc(level, tok2, paramEnd))
{
// if nothing non-const was found. write error..
if (checkConstFunc(paramStart, paramEnd))
{
for (int k = nestInfo.size() - 2; k >= 0; k--)
classname = std::string(nestInfo[k].className + "::" + classname);
checkConstError2(found, tok2, classname, functionName);
}
}
}
}
}
}
}
}
}
}
bool CheckClass::sameFunc(int nest, const Token *firstEnd, const Token *secondEnd)
{
// check return type (search backwards until previous statement)
const Token * firstStart = firstEnd->link()->tokAt(-2);
const Token * secondStart = secondEnd->link()->tokAt((-2 * nest) - 2);
bool firstDone = false;
bool secondDone = false;
while (true)
{
firstDone = false;
secondDone = false;
if (!firstStart || Token::Match(firstStart, ";|}|{|public:|protected:|private:"))
firstDone = true;
if (!secondStart || Token::Match(secondStart, ";|}|{|public:|protected:|private:"))
secondDone = true;
if (firstDone != secondDone)
return false;
// both done and match
if (firstDone)
break;
if (secondStart->str() != firstStart->str())
return false;
firstStart = firstStart->previous();
secondStart = secondStart->previous();
}
// check parameter types (names can be different or missing)
firstStart = firstEnd->link()->next();
secondStart = secondEnd->link()->next();
while (true)
{
firstDone = false;
secondDone = false;
bool again = true;
while (again)
{
again = false;
if (firstStart == firstEnd)
firstDone = true;
if (secondStart == secondEnd)
secondDone = true;
// possible difference in number of parameters
if (firstDone != secondDone)
{
// check for missing names
if (firstDone)
{
if (secondStart->varId() != 0)
again = true;
}
else
{
if (firstStart->varId() != 0)
again = true;
}
if (!again)
return false;
}
// both done and match
if (firstDone && !again)
return true;
if (firstStart->varId() != 0)
{
// skip variable name
firstStart = firstStart->next();
again = true;
}
if (secondStart->varId() != 0)
{
// skip variable name
secondStart = secondStart->next();
again = true;
}
}
if (firstStart->str() != secondStart->str())
return false;
// retry after skipped variable names
if (!again)
{
firstStart = firstStart->next();
secondStart = secondStart->next();
}
}
return true;
}
bool CheckClass::checkConstFunc(const Token *paramStart, const Token *paramEnd)
{
// if the function doesn't have any assignment nor function call,
// it can be a const function..
unsigned int indentlevel = 0;
bool isconst = true;
for (const Token *tok3 = paramEnd; tok3; tok3 = tok3->next())
{
if (tok3->str() == "{")
++indentlevel;
else if (tok3->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
// assignment.. = += |= ..
else if (tok3->str() == "=" ||
(tok3->str().find("=") == 1 &&
tok3->str().find_first_of("<>") == std::string::npos))
{
if (tok3->str() == "=") // assignment.. =
{
const Token * param = findParameter(tok3->previous(), paramStart, paramEnd);
if (param)
{
// assignment to function argument reference can be const
// f(type & x) { x = something; }
if (param->tokAt(-1)->str() == "&")
continue;
// assignment to function argument pointer can be const
// f(type * x) { *x = something; }
else if ((param->tokAt(-1)->str() == "*") &&
(tok3->tokAt(-2)->str() == "*"))
continue;
}
}
isconst = false;
break;
}
// increment/decrement (member variable?)..
else if (Token::Match(tok3, "++|--"))
{
isconst = false;
break;
}
// function call..
else if (tok3->str() != "return" && Token::Match(tok3, "%var% ("))
{
isconst = false;
break;
}
// delete..
else if (tok3->str() == "delete")
{
isconst = false;
break;
}
}
return isconst;
}
void CheckClass::checkConstError(const Token *tok, const std::string &classname, const std::string &funcname)
{
reportError(tok, Severity::style, "functionConst", "The function '" + classname + "::" + funcname + "' can be const");
}
void CheckClass::checkConstError2(const Token *tok1, const Token *tok2, const std::string &classname, const std::string &funcname)
{
std::list toks;
toks.push_back(tok1);
toks.push_back(tok2);
reportError(toks, Severity::style, "functionConst", "The function '" + classname + "::" + funcname + "' can be const");
}
void CheckClass::noConstructorError(const Token *tok, const std::string &classname, bool isStruct)
{
reportError(tok, Severity::style, "noConstructor", "The " + std::string(isStruct ? "struct" : "class") + " '" + classname + "' has no constructor. Member variables not initialized.");
}
void CheckClass::uninitVarError(const Token *tok, const std::string &classname, const std::string &varname, bool hasPrivateConstructor)
{
reportError(tok, hasPrivateConstructor ? Severity::possibleStyle : Severity::style, "uninitVar", "Member variable not initialized in the constructor '" + classname + "::" + varname + "'");
}
void CheckClass::operatorEqVarError(const Token *tok, const std::string &classname, const std::string &varname)
{
reportError(tok, Severity::possibleStyle, "operatorEqVarError", "Member variable '" + classname + "::" + varname + "' is not assigned a value in '" + classname + "::operator=" + "'");
}
void CheckClass::unusedPrivateFunctionError(const Token *tok, const std::string &classname, const std::string &funcname)
{
reportError(tok, Severity::style, "unusedPrivateFunction", "Unused private function '" + classname + "::" + funcname + "'");
}
void CheckClass::memsetClassError(const Token *tok, const std::string &memfunc)
{
reportError(tok, Severity::error, "memsetClass", "Using '" + memfunc + "' on class");
}
void CheckClass::memsetStructError(const Token *tok, const std::string &memfunc, const std::string &classname)
{
reportError(tok, Severity::error, "memsetStruct", "Using '" + memfunc + "' on struct that contains a 'std::" + classname + "'");
}
void CheckClass::operatorEqReturnError(const Token *tok)
{
reportError(tok, Severity::style, "operatorEq", "'operator=' should return something");
}
void CheckClass::virtualDestructorError(const Token *tok, const std::string &Base, const std::string &Derived)
{
reportError(tok, Severity::error, "virtualDestructor", "Class " + Base + " which is inherited by class " + Derived + " does not have a virtual destructor");
}
void CheckClass::operatorEqRetRefThisError(const Token *tok)
{
reportError(tok, Severity::style, "operatorEqRetRefThis", "'operator=' should return reference to self");
}
void CheckClass::operatorEqToSelfError(const Token *tok)
{
reportError(tok, Severity::possibleStyle, "operatorEqToSelf", "'operator=' should check for assignment to self");
}