cppcheck/checkclass.cpp

753 lines
24 KiB
C++

/*
* cppcheck - c/c++ syntax checking
* Copyright (C) 2007-2009 Daniel Marjamäki, Reijo Tomperi, Nicolas Le Cam
*
* 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 <http://www.gnu.org/licenses/
*/
//---------------------------------------------------------------------------
#include "checkclass.h"
#include <locale>
#include <string>
#include <sstream>
#include <cstring>
#include <algorithm>
#ifdef __BORLANDC__
#include <ctype.h>
#include <mem.h>
#endif
//---------------------------------------------------------------------------
CheckClass::CheckClass(const Tokenizer *tokenizer, const Settings &settings, ErrorLogger *errorLogger)
{
_tokenizer = tokenizer;
_settings = settings;
_errorLogger = errorLogger;
}
CheckClass::~CheckClass()
{
}
//---------------------------------------------------------------------------
struct CheckClass::VAR *CheckClass::ClassChecking_GetVarList(const Token *tok1)
{
// Get variable list..
struct VAR *varlist = NULL;
unsigned int indentlevel = 0;
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;
// "private:" "public:" "protected:" etc
bool b = bool((*tok->strAt(0) != ':') && strchr(tok->strAt(0), ':') != 0);
// Search for start of statement..
if (! Token::Match(tok, "[;{}]") && ! b)
continue;
// This is the start of a statement
const Token *next = tok->next();
const char *varname = 0;
// Is it a variable declaration?
if (Token::Match(next, "%type% %var% ;"))
{
if (next->isStandardType())
varname = next->strAt(1);
}
// Pointer?
else if (Token::Match(next, "%type% * %var% ;"))
{
varname = next->strAt(2);
}
// If the varname was set in one of the two if-block above, create a entry for this variable..
if (varname)
{
struct VAR *var = new VAR;
memset(var, 0, sizeof(struct VAR));
var->name = varname;
var->init = false;
var->next = varlist;
varlist = var;
}
}
return varlist;
}
//---------------------------------------------------------------------------
const Token * CheckClass::FindClassFunction(const Token *tok, const char classname[], const char funcname[], int &indentlevel)
{
if (indentlevel < 0 || tok == NULL)
return NULL;
std::ostringstream classPattern;
classPattern << "class " << classname << " :|{";
std::ostringstream internalPattern;
internalPattern << funcname << " (";
std::ostringstream externalPattern;
externalPattern << classname << " :: " << funcname << " (";
for (;tok; tok = tok->next())
{
if (indentlevel == 0 && Token::Match(tok, classPattern.str().c_str()))
{
while (tok && tok->str() != "{")
tok = tok->next();
if (tok)
tok = tok->next();
if (! tok)
break;
indentlevel = 1;
}
if (tok->str() == "{")
{
// If indentlevel==0 don't go to indentlevel 1. Skip the block.
if (indentlevel > 0)
++indentlevel;
else
{
for (; tok; tok = tok->next())
{
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
{
--indentlevel;
if (indentlevel <= 0)
break;
}
}
if (tok == NULL)
return NULL;
continue;
}
}
if (tok->str() == "}")
{
--indentlevel;
if (indentlevel < 0)
return NULL;
}
if (indentlevel == 1)
{
// Member function implemented in the class declaration?
if (tok->str() != "~" && Token::Match(tok->next(), internalPattern.str().c_str()))
{
const Token *tok2 = tok;
while (tok2 && tok2->str() != "{" && tok2->str() != ";")
tok2 = tok2->next();
if (tok2 && tok2->str() == "{")
return tok->next();
}
}
else if (indentlevel == 0 && Token::Match(tok, externalPattern.str().c_str()))
{
return tok;
}
}
// Not found
return NULL;
}
//---------------------------------------------------------------------------
void CheckClass::InitVar(struct VAR *varlist, const char varname[])
{
for (struct VAR *var = varlist; var; var = var->next)
{
if (strcmp(var->name, varname) == 0)
{
var->init = true;
break;
}
}
}
//---------------------------------------------------------------------------
void CheckClass::ClassChecking_VarList_Initialize(const Token *tok1, const Token *ftok, struct VAR *varlist, const char classname[], std::list<std::string> &callstack)
{
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->aaaa());
}
Assign |= (ftok->str() == ":");
}
if (ftok->str() == "{")
{
++indentlevel;
Assign = false;
}
if (ftok->str() == "}")
{
if (indentlevel <= 1)
break;
--indentlevel;
}
if (indentlevel < 1)
continue;
// 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 (struct VAR *var = varlist; var; var = var->next)
var->init = true;
break;
}
if (!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(2);
// Clearing all variables..
if (Token::simpleMatch(ftok, "memset ( this ,"))
{
for (struct VAR *var = varlist; var; var = var->next)
var->init = true;
break;
}
// 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 = FindClassFunction(tok1, classname, ftok->aaaa(), i);
ClassChecking_VarList_Initialize(tok1, ftok2, varlist, classname, callstack);
}
}
// Assignment of member variable?
else if (Token::Match(ftok, "%var% ="))
{
InitVar(varlist, ftok->aaaa());
}
// The functions 'clear' and 'Clear' are supposed to initialize variable.
if (Token::Match(ftok, "%var% . clear|Clear ("))
{
InitVar(varlist, ftok->aaaa());
}
}
}
//---------------------------------------------------------------------------
// ClassCheck: Check that all class constructors are ok.
//---------------------------------------------------------------------------
void CheckClass::constructors()
{
const char pattern_class[] = "class %var% {";
// Locate class
const Token *tok1 = Token::findmatch(_tokenizer->tokens(), pattern_class);
while (tok1)
{
const char *className[2];
className[0] = tok1->strAt(1);
className[1] = 0;
const Token *classNameToken = tok1->tokAt(1);
// TODO: handling of private constructors should be improved.
bool hasPrivateConstructor = false;
{
int indentlevel = 0;
bool isPrivate = true;
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)
{
// TODO: Handle private constructors.
// Right now to avoid false positives I 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 (Token::Match(constructor_token, "~"))
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)
{
// If the class has member variables there should be an constructor
struct VAR *varlist = ClassChecking_GetVarList(tok1);
if (varlist)
{
std::ostringstream ostr;
ostr << _tokenizer->fileLine(tok1);
ostr << " The class '" << classNameToken->str() << "' has no constructor";
_errorLogger->reportErr(ostr.str());
}
// Delete the varlist..
while (varlist)
{
struct VAR *nextvar = varlist->next;
delete varlist;
varlist = nextvar;
}
}
tok1 = Token::findmatch(tok1->next(), pattern_class);
continue;
}
// Check that all member variables are initialized..
struct VAR *varlist = ClassChecking_GetVarList(tok1);
// Check constructors
CheckConstructors(tok1, varlist, className[0]);
// Check assignment operators
CheckConstructors(tok1, varlist, "operator =");
// Delete the varlist..
while (varlist)
{
struct VAR *nextvar = varlist->next;
delete varlist;
varlist = nextvar;
}
tok1 = Token::findmatch(tok1->next(), pattern_class);
}
}
void CheckClass::CheckConstructors(const Token *tok1, struct VAR *varlist, const char funcname[])
{
const char * const className = tok1->strAt(1);
int indentlevel = 0;
const Token *constructor_token = FindClassFunction(tok1, className, funcname, indentlevel);
std::list<std::string> callstack;
ClassChecking_VarList_Initialize(tok1, constructor_token, varlist, className, callstack);
while (constructor_token)
{
// Check if any variables are uninitialized
for (struct 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
std::ostringstream ostr;
ostr << _tokenizer->fileLine(constructor_token);
ostr << " Uninitialized member variable '" << className << "::" << var->name << "'";
_errorLogger->reportErr(ostr.str());
}
for (struct VAR *var = varlist; var; var = var->next)
var->init = false;
constructor_token = FindClassFunction(constructor_token->next(), className, funcname, indentlevel);
callstack.clear();
ClassChecking_VarList_Initialize(tok1, constructor_token, varlist, className, callstack);
}
}
//---------------------------------------------------------------------------
// ClassCheck: Unused private functions
//---------------------------------------------------------------------------
void CheckClass::privateFunctions()
{
// Locate some class
for (const Token *tok1 = Token::findmatch(_tokenizer->tokens(), "class %var% {"); tok1; tok1 = Token::findmatch(tok1->next(), "class %var% {"))
{
const std::string &classname = tok1->next()->str();
// The class implementation must be available..
const std::string classconstructor(classname + " :: " + classname);
if (!Token::findmatch(_tokenizer->tokens(), classconstructor.c_str()))
continue;
// Get private functions..
std::list<std::string> FuncList;
FuncList.clear();
bool priv = false;
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 (tok->str() == "private:")
priv = true;
else if (tok->str() == "public:")
priv = false;
else if (tok->str() == "protected:")
priv = false;
else if (priv && indent_level == 1)
{
if (Token::Match(tok, "typedef %type% ("))
tok = tok->tokAt(2);
if (Token::Match(tok, "%var% (") &&
!Token::Match(tok, classname.c_str()))
{
FuncList.push_back(tok->str());
}
}
}
// Check that all private functions are used..
const std::string pattern_function(classname + " ::");
bool HasFuncImpl = false;
const Token *ftok = _tokenizer->tokens();
while (ftok)
{
ftok = Token::findmatch(ftok, pattern_function.c_str());
int numpar = 0;
while (ftok && !Token::Match(ftok, "[;{]"))
{
if (ftok->str() == "(")
++numpar;
else if (ftok->str() == ")")
--numpar;
ftok = ftok->next();
}
if (!ftok)
break;
if (ftok->str() != ";" && numpar == 0)
{
HasFuncImpl = true;
indent_level = 0;
while (ftok)
{
if (ftok->str() == "{")
++indent_level;
if (ftok->str() == "}")
{
if (indent_level <= 1)
break;
--indent_level;
}
if (Token::Match(ftok->next(), "("))
FuncList.remove(ftok->str());
ftok = ftok->next();
}
}
if (ftok)
ftok = ftok->next();
}
while (HasFuncImpl && !FuncList.empty())
{
// Final check; check if the function pointer is used somewhere..
const std::string _pattern("return|(|)|,|= " + FuncList.front());
if (!Token::findmatch(_tokenizer->tokens(), _pattern.c_str()))
{
std::ostringstream ostr;
ostr << "Class '" << classname << "', unused private function: '" << FuncList.front() << "'";
_errorLogger->reportErr(ostr.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;
// Todo: Handle memcpy and memmove
const char *type = NULL;
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 && type[0]))
continue;
// Warn if type is a class..
const std::string pattern1(std::string("class ") + type);
if (Token::findmatch(_tokenizer->tokens(), pattern1.c_str()))
{
std::ostringstream ostr;
ostr << _tokenizer->fileLine(tok) << ": Using '" << tok->str() << "' on class.";
_errorLogger->reportErr(ostr.str());
continue;
}
// Warn if type is a struct that contains any std::*
const std::string pattern2(std::string("struct ") + type);
for (const Token *tstruct = Token::findmatch(_tokenizer->tokens(), pattern2.c_str()); tstruct; tstruct = tstruct->next())
{
if (tstruct->str() == "}")
break;
if (Token::Match(tstruct, "std :: %type% %var% ;"))
{
std::ostringstream ostr;
ostr << _tokenizer->fileLine(tok) << ": Using '" << tok->str() << "' on struct that contains a 'std::" << tstruct->strAt(2) << "'";
_errorLogger->reportErr(ostr.str());
break;
}
}
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// ClassCheck: "void operator=("
//---------------------------------------------------------------------------
void CheckClass::operatorEq()
{
if (const Token *tok = Token::findmatch(_tokenizer->tokens(), "void operator = ("))
{
std::ostringstream ostr;
ostr << _tokenizer->fileLine(tok) << ": 'operator=' should return something";
_errorLogger->reportErr(ostr.str());
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// 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 = Token::Match(derived, "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 char *baseName[2];
baseName[0] = derived->strAt(0);
baseName[1] = 0;
// Update derived so it's ready for the next loop.
derived = derived->next();
if (Token::Match(derived, ","))
derived = derived->next();
// 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[0] + " (").c_str());
while (Token::Match(base, "::"))
base = Token::findmatch(base->next(), (std::string("%any% ~ ") + baseName[0] + + " (").c_str());
while (Token::Match(base, "%var%") && !Token::Match(base, "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[0] + " :|{").c_str());
if (base)
{
std::ostringstream errmsg;
errmsg << _tokenizer->fileLine(base) << ": Class " << baseName[0] << " which is inherited by class " << derivedClass->str() << " does not have a virtual destructor";
_errorLogger->reportErr(errmsg.str());
}
}
// There is a destructor. Check that it's virtual..
else if (base->str() != "virtual")
{
std::ostringstream errmsg;
errmsg << _tokenizer->fileLine(base) << ": Class " << baseName[0] << " which is inherited by class " << derivedClass->str() << " does not have a virtual destructor";
_errorLogger->reportErr(errmsg.str());
}
}
}
}
//---------------------------------------------------------------------------