cppcheck/checkclass.cpp

751 lines
24 KiB
C++

/*
* cppcheck - c/c++ syntax checking
* Copyright (C) 2007-2008 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 (!TOKEN::Match(tok,"~") && 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, "[{};)=]") && ! TOKEN::Match(ftok, "else") )
continue;
// Using the operator= function to initialize all variables..
if ( TOKEN::Match(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::Match(ftok, "this .") )
ftok = ftok->tokAt(2);
// Clearing all variables..
if (TOKEN::Match(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 (") || TOKEN::Match(ftok,"%var% . 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;
// 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::Match(tok, "%var1% (", className) )
{
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?
const TOKEN *constructor_token = TOKEN::findmatch( tok1, "%any% %var1% (", className );
while ( TOKEN::Match( constructor_token, "~" ) )
constructor_token = TOKEN::findmatch( constructor_token->next(), "%any% %var1% (", className );
// 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 '" << className[0] << "' 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(), "%any% ~ %var1% (", baseName);
while (TOKEN::Match(base, "::"))
base = TOKEN::findmatch(base->next(), "%any% ~ %var1% (", baseName);
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(), "class %var1% :|{", baseName);
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 ( ! TOKEN::Match(base, "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());
}
}
}
}
//---------------------------------------------------------------------------