cppcheck/src/checkmemoryleak.cpp

1846 lines
57 KiB
C++

/*
* 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 <http://www.gnu.org/licenses/
*/
#include "checkmemoryleak.h"
#include "mathlib.h"
#include "tokenize.h"
#include <algorithm>
#include <cstring>
#include <iostream>
#include <sstream>
//---------------------------------------------------------------------------
// Register this check class (by creating a static instance of it)
namespace
{
CheckMemoryLeakInFunction instance1;
CheckMemoryLeakInClass instance2;
}
//---------------------------------------------------------------------------
bool CheckMemoryLeak::isclass(const Tokenizer *_tokenizer, const Token *tok) const
{
if (tok->isStandardType())
return false;
std::ostringstream pattern;
pattern << "struct " << tok->str();
if (Token::findmatch(_tokenizer->tokens(), pattern.str().c_str()))
return false;
return true;
}
//---------------------------------------------------------------------------
CheckMemoryLeak::AllocType CheckMemoryLeak::GetAllocationType(const Token *tok2) const
{
// What we may have...
// * var = (char *)malloc(10);
// * var = new char[10];
// * var = strdup("hello");
// * var = strndup("hello", 3);
if (tok2 && tok2->str() == "(")
{
while (tok2 && tok2->str() != ")")
tok2 = tok2->next();
tok2 = tok2 ? tok2->next() : NULL;
}
if (! tok2)
return No;
if (! tok2->isName())
return No;
// Does tok2 point on "malloc", "strdup" or "kmalloc"..
static const char * const mallocfunc[] = {"malloc",
"calloc",
"strdup",
"strndup",
"kmalloc",
"kzalloc",
"kcalloc",
0
};
for (unsigned int i = 0; mallocfunc[i]; i++)
{
if (tok2->str() == mallocfunc[i])
return Malloc;
}
// Does tok2 point on "g_malloc", "g_strdup", ..
static const char * const gmallocfunc[] = {"g_new",
"g_new0",
"g_try_new",
"g_try_new0",
"g_malloc",
"g_malloc0",
"g_try_malloc",
"g_try_malloc0",
"g_strdup",
"g_strndup",
0
};
for (unsigned int i = 0; gmallocfunc[i]; i++)
{
if (tok2->str() == gmallocfunc[i])
return gMalloc;
}
if (Token::Match(tok2, "new %type% [;()]") ||
Token::Match(tok2, "new ( std :: nothrow ) %type% [;()]") ||
Token::Match(tok2, "new ( nothrow ) %type% [;()]"))
return New;
if (Token::Match(tok2, "new %type% [") ||
Token::Match(tok2, "new ( std :: nothrow ) %type% [") ||
Token::Match(tok2, "new ( nothrow ) %type% ["))
return NewArray;
if (Token::Match(tok2, "fopen|tmpfile ("))
return File;
if (Token::simpleMatch(tok2, "popen ("))
return Pipe;
if (Token::Match(tok2, "opendir|fdopendir ("))
return Dir;
return No;
}
CheckMemoryLeak::AllocType CheckMemoryLeak::GetReallocationType(const Token *tok2)
{
// What we may have...
// * var = (char *)realloc(..;
if (tok2 && tok2->str() == "(")
{
while (tok2 && tok2->str() != ")")
tok2 = tok2->next();
tok2 = tok2 ? tok2->next() : NULL;
}
if (! tok2)
return No;
if (Token::simpleMatch(tok2, "realloc"))
return Malloc;
// GTK memory reallocation..
if (Token::Match(tok2, "g_realloc|g_try_realloc|g_renew|g_try_renew"))
return gMalloc;
return No;
}
CheckMemoryLeak::AllocType CheckMemoryLeak::GetDeallocationType(const Token *tok, const char *varnames[])
{
int i = 0;
std::string names;
while (varnames[i])
{
if (i > 0)
names += " . ";
names += varnames[i];
i++;
}
if (Token::simpleMatch(tok, std::string("delete " + names + " ;").c_str()))
return New;
if (Token::simpleMatch(tok, std::string("delete [ ] " + names + " ;").c_str()))
return NewArray;
if (Token::simpleMatch(tok, std::string("delete ( " + names + " ) ;").c_str()))
return New;
if (Token::simpleMatch(tok, std::string("delete [ ] ( " + names + " ) ;").c_str()))
return NewArray;
if (Token::simpleMatch(tok, std::string("free ( " + names + " ) ;").c_str()) ||
Token::simpleMatch(tok, std::string("kfree ( " + names + " ) ;").c_str()))
return Malloc;
if (Token::simpleMatch(tok, std::string("g_free ( " + names + " ) ;").c_str()))
return gMalloc;
if (Token::simpleMatch(tok, std::string("fclose ( " + names + " )").c_str()) ||
Token::simpleMatch(tok, "fcloseall ( )"))
return File;
if (Token::simpleMatch(tok, std::string("pclose ( " + names + " )").c_str()))
return Pipe;
if (Token::simpleMatch(tok, std::string("closedir ( " + names + " )").c_str()))
return Dir;
return No;
}
//--------------------------------------------------------------------------
//--------------------------------------------------------------------------
void CheckMemoryLeak::MemoryLeak(const Token *tok, const char varname[], AllocType alloctype, bool all)
{
if (alloctype == CheckMemoryLeak::File ||
alloctype == CheckMemoryLeak::Pipe ||
alloctype == CheckMemoryLeak::Dir)
resourceLeakError(tok, varname);
else if (all)
memleakallError(tok, varname);
else
memleakError(tok, varname);
}
//---------------------------------------------------------------------------
void CheckMemoryLeak::memleakError(const Token *tok, const std::string &varname)
{
error(tok, "error", "memleak", "Memory leak: " + varname);
}
void CheckMemoryLeak::memleakallError(const Token *tok, const std::string &varname)
{
error(tok, "all", "memleakall", "Memory leak: " + varname);
}
void CheckMemoryLeak::resourceLeakError(const Token *tok, const std::string &varname)
{
error(tok, "error", "resourceLeak", "Resource leak: " + varname);
}
void CheckMemoryLeak::deallocDeallocError(const Token *tok, const std::string &varname)
{
error(tok, "error", "deallocDealloc", "Deallocating a deallocated pointer: " + varname);
}
void CheckMemoryLeak::deallocuseError(const Token *tok, const std::string &varname)
{
error(tok, "error", "deallocuse", "Using '" + varname + "' after it is deallocated / released");
}
void CheckMemoryLeak::mismatchSizeError(const Token *tok, const std::string &sz)
{
error(tok, "error", "mismatchSize", "The given size " + sz + " is mismatching");
}
void CheckMemoryLeak::mismatchAllocDealloc(const std::list<const Token *> &callstack, const std::string &varname)
{
error(callstack, "error", "mismatchAllocDealloc", "Mismatching allocation and deallocation: " + varname);
}
CheckMemoryLeak::AllocType CheckMemoryLeak::functionReturnType(const Token *tok) const
{
// Locate the start of the function..
unsigned int parlevel = 0;
while (tok)
{
if (tok->str() == "{" || tok->str() == "}")
return No;
if (tok->str() == "(")
{
if (parlevel != 0)
return No;
++parlevel;
}
else if (tok->str() == ")")
{
if (parlevel != 1)
return No;
break;
}
tok = tok->next();
}
// Is this the start of a function?
if (!Token::Match(tok, ") const| {"))
return No;
while (tok->str() != "{")
tok = tok->next();
tok = tok ? tok->next() : 0;
// Inspect the statements..
std::string varname;
AllocType allocType = No;
while (tok)
{
// variable declaration..
if (Token::Match(tok, "%type% * %var% ;"))
{
tok = tok->tokAt(4);
continue;
}
if (varname.empty() && Token::Match(tok, "%var% = "))
{
varname = tok->str();
allocType = GetAllocationType(tok->tokAt(2));
if (allocType == No)
return No;
while (tok && tok->str() != ";")
tok = tok->next();
tok = tok ? tok->next() : 0;
continue;
}
if (tok->str() == "return")
{
if (varname.size() && Token::Match(tok->next(), (varname + " ;").c_str()))
return allocType;
if (Token::Match(tok, "return new %type% ;"))
return New;
if (Token::Match(tok, "return new %type% [ %any% ] ;"))
return NewArray;
}
return No;
}
return No;
}
bool CheckMemoryLeakInFunction::MatchFunctionsThatReturnArg(const Token *tok, const std::string &varname)
{
return Token::Match(tok, std::string("; " + varname + " = strcat|memcpy|memmove|strcpy ( " + varname + " ,").c_str());
}
bool CheckMemoryLeakInFunction::notvar(const Token *tok, const char *varnames[], bool endpar)
{
std::string varname;
for (int i = 0; varnames[i]; i++)
{
if (i > 0)
varname += " . ";
varname += varnames[i];
}
const std::string end(endpar ? " &&|)" : " [;)&|]");
return bool(Token::Match(tok, ("! " + varname + end).c_str()) ||
Token::Match(tok, ("! ( " + varname + " )" + end).c_str()));
}
static int countParameters(const Token *tok)
{
if (!Token::Match(tok, "%var% ("))
return -1;
if (Token::Match(tok->tokAt(2), "void| )"))
return 0;
int numpar = 1;
int parlevel = 0;
for (; tok; tok = tok->next())
{
if (tok->str() == "(")
++parlevel;
else if (tok->str() == ")")
{
if (parlevel <= 1)
return numpar;
--parlevel;
}
else if (parlevel == 1 && tok->str() == ",")
++numpar;
}
return -1;
}
const char * CheckMemoryLeakInFunction::call_func(const Token *tok, std::list<const Token *> callstack, const char *varnames[], AllocType &alloctype, AllocType &dealloctype, bool &all, unsigned int sz)
{
// Keywords that are not function calls..
if (Token::Match(tok, "if|for|while|return|switch"))
return 0;
// String functions that are not allocating nor deallocating memory..
if (Token::Match(tok, "strcpy|strncpy|strcat|strncat|strcmp|strncmp|strcasecmp|stricmp|sprintf|strchr|strrchr|strstr"))
return 0;
// Memory functions that are not allocating nor deallocating memory..
if (Token::Match(tok, "memset|memcpy|memmove|memchr"))
return 0;
// I/O functions that are not allocating nor deallocating memory..
if (Token::Match(tok, "fgets|fgetc|fputs|fputc|feof|ferror|clearerr|printf|fprintf") ||
Token::Match(tok, "fread|fwrite|fflush|fseek|fseeko|ftell|ftello|fsetpos|fgetpos") ||
Token::Match(tok, "setvbuf|setbuf|setbuffer|setlinebuf|rewind"))
return 0;
// Functions to work with directories that are not allocating nor
// deallocating memory..
if (Token::Match(tok, "readdir|readdir_r|rewinddir|telldir|seekdir|scandir"))
return 0;
// Convert functions that are not allocating nor deallocating memory..
if (Token::Match(tok, "atoi|atof|atol|strtol|strtoul|strtod"))
return 0;
// This is not an unknown function neither
if (tok->str() == "delete")
return 0;
if (GetAllocationType(tok) != No || GetReallocationType(tok) != No || GetDeallocationType(tok, varnames) != No)
return 0;
if (callstack.size() > 2)
return "dealloc_";
const std::string funcname(tok->str());
for (std::list<const Token *>::const_iterator it = callstack.begin(); it != callstack.end(); ++it)
{
if ((*it)->str() == funcname)
return "recursive";
}
callstack.push_back(tok);
// Check if this is a function that allocates memory..
{
const Token *ftok = _tokenizer->GetFunctionTokenByName(funcname.c_str());
AllocType a = functionReturnType(ftok);
if (a != No)
return "alloc";
}
// how many parameters is there in the function call?
int numpar = countParameters(tok);
if (numpar <= 0)
return "callfunc";
int par = 1;
int parlevel = 0;
std::string pattern = "[,()] ";
for (int i = 0; varnames[i]; i++)
{
if (i > 0)
pattern += " . ";
pattern += varnames[i];
}
pattern += " [,()]";
for (; tok; tok = tok->next())
{
if (tok->str() == "(")
++parlevel;
else if (tok->str() == ")")
{
--parlevel;
if (parlevel < 1)
{
return _settings->_showAll ? 0 : "callfunc";
}
}
if (parlevel == 1)
{
if (tok->str() == ",")
++par;
if (Token::Match(tok, pattern.c_str()))
{
const Token *ftok = _tokenizer->GetFunctionTokenByName(funcname.c_str());
// how many parameters does the function want?
if (numpar != countParameters(ftok))
return "recursive";
const char *parname = Tokenizer::getParameterName(ftok, par);
if (! parname)
return "recursive";
// Check if the function deallocates the variable..
while (ftok && (ftok->str() != "{"))
ftok = ftok->next();
Token *func = getcode(ftok->tokAt(1), callstack, parname, alloctype, dealloctype, false, all, sz);
simplifycode(func, all);
const Token *func_ = func;
while (func_ && func_->str() == ";")
func_ = func_->next();
const char *ret = 0;
// TODO : "goto" isn't handled well
if (Token::findmatch(func_, "dealloc"))
ret = "dealloc";
else if (Token::findmatch(func_, "use"))
ret = "use";
else if (Token::findmatch(func_, "&use"))
ret = "&use";
Tokenizer::deleteTokens(func);
return ret;
}
}
}
return NULL;
}
Token *CheckMemoryLeakInFunction::getcode(const Token *tok, std::list<const Token *> callstack, const char varname[], AllocType &alloctype, AllocType &dealloctype, bool classmember, bool &all, unsigned int sz)
{
const char *varnames[2];
varnames[0] = varname;
varnames[1] = 0;
std::string varnameStr = varname;
Token *rethead = 0, *rettail = 0;
#define addtoken(_str) \
{ \
if (rettail) \
{ \
rettail->insertToken(_str); \
rettail = rettail->next(); \
} \
else \
{ \
rethead = new Token; \
rettail = rethead; \
rettail->str(_str); \
} \
\
rettail->linenr( tok->linenr() ); \
rettail->fileIndex( tok->fileIndex() ); \
}
// The first token should be ";"
addtoken(";");
bool isloop = false;
int indentlevel = 0;
int parlevel = 0;
for (; tok; tok = tok->next())
{
if (tok->str() == "{")
{
addtoken("{");
++indentlevel;
}
else if (tok->str() == "}")
{
addtoken("}");
if (indentlevel <= 0)
break;
--indentlevel;
}
if (tok->str() == "(")
++parlevel;
else if (tok->str() == ")")
--parlevel;
isloop &= (parlevel > 0);
if (parlevel == 0 && tok->str() == ";")
addtoken(";");
if (Token::Match(tok->previous(), std::string("[(;{}] " + varnameStr + " =").c_str()))
{
AllocType alloc = GetAllocationType(tok->tokAt(2));
bool realloc = false;
if (sz > 1 &&
Token::Match(tok->tokAt(2), "malloc ( %num% )") &&
(MathLib::toLongNumber(tok->strAt(4)) % sz) != 0)
{
mismatchSizeError(tok->tokAt(4), tok->strAt(4));
}
if (alloc == No)
{
alloc = GetReallocationType(tok->tokAt(2));
if (alloc != No)
{
addtoken("realloc");
addtoken(";");
realloc = true;
}
}
// If "--all" hasn't been given, don't check classes..
if (alloc == New)
{
if (Token::Match(tok->tokAt(2), "new %type% [(;]"))
{
if (isclass(_tokenizer, tok->tokAt(3)))
{
if (_settings->_showAll)
{
if (_settings->isAutoDealloc(tok->strAt(3)))
{
// This class has automatic deallocation
alloc = No;
}
else
{
// The checking will proceed.. but any error messages that are shown are shown thanks to "--all"
all = true;
}
}
else
alloc = No;
}
}
}
if (alloc != No)
{
if (! realloc)
addtoken("alloc");
if (alloctype != No && alloctype != alloc)
alloc = Many;
if (alloc != Many && dealloctype != No && dealloctype != Many && dealloctype != alloc)
{
callstack.push_back(tok);
mismatchAllocDealloc(callstack, varname);
callstack.pop_back();
}
alloctype = alloc;
}
else if (MatchFunctionsThatReturnArg(tok->previous(), std::string(varname)))
{
addtoken("use");
}
// assignment..
else
{
// is the pointer in rhs?
bool rhs = false;
std::string pattern("[=+] " + std::string(varname));
for (const Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() == ";")
break;
if (Token::Match(tok2, pattern.c_str()))
{
rhs = true;
break;
}
}
addtoken((rhs ? "use" : "assign"));
}
}
if (Token::Match(tok->previous(), "[;{})=] %var%"))
{
AllocType dealloc = GetDeallocationType(tok, varnames);
if (dealloc != No)
{
addtoken("dealloc");
if (dealloctype != No && dealloctype != dealloc)
dealloc = Many;
if (dealloc != Many && alloctype != No && alloctype != Many && alloctype != dealloc)
{
callstack.push_back(tok);
mismatchAllocDealloc(callstack, varname);
callstack.pop_back();
}
dealloctype = dealloc;
continue;
}
}
// if else switch
if (tok->str() == "if")
{
if (Token::simpleMatch(tok, std::string("if ( " + varnameStr + " )").c_str()) ||
Token::simpleMatch(tok, std::string("if ( " + varnameStr + " != 0 )").c_str()) ||
Token::simpleMatch(tok, std::string("if ( 0 != " + varnameStr + " )").c_str()))
{
addtoken("if(var)");
// Make sure the "use" will not be added
while (tok->str() != ")")
tok = tok->next();
}
else if (Token::simpleMatch(tok, "if (") && notvar(tok->tokAt(2), varnames, true))
{
addtoken("if(!var)");
}
else
{
// Check if the condition depends on var somehow..
bool dep = false;
int parlevel = 0;
for (const Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "(")
++parlevel;
if (tok2->str() == ")")
{
--parlevel;
if (parlevel <= 0)
break;
}
if (Token::Match(tok2, std::string("fclose|closedir ( " + varnameStr + " )").c_str()))
{
addtoken("dealloc");
addtoken(";");
dep = true;
break;
}
if ((tok2->str() != ".") &&
Token::simpleMatch(tok2->next(), varnameStr.c_str()) &&
!Token::simpleMatch(tok2->next(), std::string(varnameStr + " .").c_str()))
{
dep = true;
break;
}
}
if (Token::simpleMatch(tok, std::string("if ( ! " + varnameStr + " &&").c_str()))
{
addtoken("if(!var)");
}
else if (tok->next() &&
tok->next()->link() &&
Token::simpleMatch(tok->next()->link()->tokAt(-3), std::string("&& ! " + varnameStr).c_str()))
{
addtoken("if(!var)");
}
else
{
addtoken((dep ? "ifv" : "if"));
}
}
}
if ((tok->str() == "else") || (tok->str() == "switch"))
{
addtoken(tok->str().c_str());
}
else if ((tok->str() == "case"))
{
addtoken("case");
addtoken(";");
}
else if ((tok->str() == "default"))
{
addtoken("default");
addtoken(";");
}
// Loops..
else if ((tok->str() == "for") || (tok->str() == "while"))
{
addtoken("loop");
isloop = true;
}
else if ((tok->str() == "do"))
{
addtoken("do");
}
if (isloop && notvar(tok, varnames))
addtoken("!var");
// continue / break..
if (tok->str() == "continue")
addtoken("continue");
if (tok->str() == "break")
addtoken("break");
// goto..
if (tok->str() == "goto")
{
addtoken("goto");
}
// Return..
else if (tok->str() == "return")
{
addtoken("return");
// Returning a auto_ptr of this allocated variable..
if (Token::simpleMatch(tok->next(), "std :: auto_ptr <"))
{
const Token *tok2 = tok->tokAt(5);
while (tok2 && tok2->str() != ">")
tok2 = tok2->next();
if (Token::simpleMatch(tok2, ("> ( " + varnameStr + " )").c_str()))
{
addtoken("use");
tok = tok2->tokAt(3);
}
}
else if (Token::Match(tok, ("return &| " + varnameStr).c_str()))
{
addtoken("use");
}
else if (Token::simpleMatch(tok->next(), "("))
{
int parlevel = 1;
for (const Token *tok2 = tok->tokAt(2); tok2; tok2 = tok2->next())
{
if (tok2->str() == "(")
++parlevel;
else if (tok2->str() == ")")
{
if (parlevel <= 1)
break;
--parlevel;
}
if (tok2->str() == varname)
{
addtoken("use");
break;
}
}
}
else if (Token::Match(tok, ("return strcpy|strncpy|memcpy ( " + varnameStr).c_str()))
{
addtoken("use");
tok = tok->tokAt(2);
}
}
// throw..
else if (Token::Match(tok, "try|throw|catch"))
addtoken(tok->strAt(0));
// exit..
if (Token::Match(tok->previous(), "[{};] exit ( %any% ) ;"))
addtoken("exit");
// Assignment..
if (Token::Match(tok, std::string("[)=] " + varnameStr + " [+;)]").c_str()) ||
Token::Match(tok, std::string(varnameStr + " +=|-=").c_str()) ||
Token::Match(tok, std::string("+=|<< " + varnameStr + " ;").c_str()) ||
Token::Match(tok, std::string("= strcpy|strcat|memmove|memcpy ( " + varnameStr + " ,").c_str()))
{
addtoken("use");
}
else if (Token::Match(tok->previous(), std::string("[;{}=(,+-*/] " + varnameStr + " [").c_str()))
{
addtoken("use_");
}
// Investigate function calls..
if (Token::Match(tok, "%var% ("))
{
// Inside class function.. if the var is passed as a parameter then
// just add a "::use"
// The "::use" means that a member function was probably called but it wasn't analyzed further
if (classmember)
{
int parlevel = 1;
for (const Token *tok2 = tok->tokAt(2); tok2; tok2 = tok2->next())
{
if (tok2->str() == "(")
++parlevel;
else if (tok2->str() == ")")
{
--parlevel;
if (parlevel <= 0)
break;
}
if (tok2->str() == varnameStr)
{
addtoken("::use");
break;
}
}
}
else
{
const char *str = call_func(tok, callstack, varnames, alloctype, dealloctype, all, sz);
if (str)
addtoken(str);
}
}
// Callback..
bool matchFirst;
if ((matchFirst = Token::Match(tok, "( %var%")) ||
Token::Match(tok, "( * %var%"))
{
int tokIdx = matchFirst ? 2 : 3;
while (Token::simpleMatch(tok->tokAt(tokIdx), ".") &&
Token::Match(tok->tokAt(tokIdx + 1), "%var%"))
tokIdx += 2;
if (Token::simpleMatch(tok->tokAt(tokIdx), ") ("))
{
for (const Token *tok2 = tok->tokAt(tokIdx + 2); tok2; tok2 = tok2->next())
{
if (Token::Match(tok2, "[;{]"))
break;
else if (tok2->str() == varname)
{
addtoken("use");
break;
}
}
}
}
// Linux lists..
if (Token::Match(tok, std::string("[=(,] & " + varnameStr + " [.[,)]").c_str()))
{
addtoken("&use");
}
}
return rethead;
}
void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
{
// Replace "throw" that is not in a try block with "return"
int indentlevel = 0;
int trylevel = -1;
for (Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "{")
++indentlevel;
else if (tok2->str() == "}")
{
--indentlevel;
if (indentlevel <= trylevel)
trylevel = -1;
}
else if (trylevel == -1 && tok2->str() == "try")
trylevel = indentlevel;
else if (trylevel == -1 && tok2->str() == "throw")
tok2->str("return");
}
// simplify "exit".. remove everything in its execution path
for (Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() != "exit")
continue;
// Found an "exit".. try to remove everything before it
Token *tokEnd = tok2->next();
int indentlevel = 0;
while (tok2->previous())
{
tok2 = tok2->previous();
if (tok2->str() == "}")
{
indentlevel--;
}
else if (tok2->str() == "{")
{
if (indentlevel == 0)
break;
indentlevel++;
}
}
Token::eraseTokens(tok2, tokEnd);
tok2 = tokEnd;
}
// reduce the code..
bool done = false;
while (! done)
{
done = true;
for (Token *tok2 = tok; tok2; tok2 = tok2 ? tok2->next() : NULL)
{
// Delete extra ";"
while (Token::Match(tok2, "[;{}] ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Replace "{ }" with ";"
if (Token::simpleMatch(tok2->next(), "{ }"))
{
tok2->next()->str(";");
Token::eraseTokens(tok2->next(), tok2->tokAt(3));
done = false;
}
// Delete braces around a single instruction..
if (Token::Match(tok2->next(), "{ %var% ; }"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
Token::eraseTokens(tok2->tokAt(2), tok2->tokAt(4));
done = false;
}
if (Token::Match(tok2->next(), "{ %var% %var% ; }"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
Token::eraseTokens(tok2->tokAt(3), tok2->tokAt(5));
done = false;
}
// Reduce "if if" => "if"
else if (Token::Match(tok2, "if if|callfunc"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
else if (Token::simpleMatch(tok2->next(), "if"))
{
// Delete empty if that is not followed by an else
if (Token::Match(tok2->next(), "if ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Delete "if ; else ;"
else if (Token::simpleMatch(tok2->next(), "if ; else ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Two "if alloc ;" after one another.. perhaps only one of them can be executed each time
else if (!_settings->_showAll && Token::Match(tok2, "[;{}] if alloc ; if alloc ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// TODO Make this more generic. Delete "if ; else use ; use"
else if (Token::Match(tok2, "; if ; else assign|use ; assign|use") ||
Token::Match(tok2, "; if assign|use ; else ; assign|use"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Reduce "if assign|dealloc|use ;" that is not followed by an else..
// If "--all" has been given these are deleted
// Otherwise, only the "if" will be deleted
else if (Token::Match(tok2, "[;{}] if assign|dealloc|use ; !!else"))
{
if (_settings->_showAll)
{
Token::eraseTokens(tok2, tok2->tokAt(3));
all = true;
}
else
{
Token::eraseTokens(tok2, tok2->tokAt(2));
}
done = false;
}
// Reduce "if return ; alloc ;" => "alloc ;"
else if (Token::Match(tok2, "[;{}] if return ; alloc ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// "[;{}] if alloc ; else return ;" => "[;{}] alloc ;"
else if (Token::Match(tok2, "[;{}] if alloc ; else return ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2)); // Remove "if"
Token::eraseTokens(tok2->next(), tok2->tokAt(5)); // Remove "; else return"
done = false;
}
// Reduce "if ; else %var% ;" => "if %var% ;"
else if (Token::Match(tok2->next(), "if ; else %var% ;"))
{
Token::eraseTokens(tok2->next(), tok2->tokAt(4));
done = false;
}
// Reduce "if ; else return use ;" => "if return use ;"
else if (Token::simpleMatch(tok2->next(), "if ; else return use ;"))
{
Token::eraseTokens(tok2->next(), tok2->tokAt(4));
done = false;
}
// Reduce "if return ; if return ;" => "if return ;"
else if (Token::simpleMatch(tok2->next(), "if return ; if return ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Delete first if in .. "if { dealloc|assign|use ; return ; } if return ;"
else if (Token::Match(tok2, "[;{}] if { dealloc|assign|use ; return ; } if return ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(8));
done = false;
}
// Remove "if { dealloc ; callfunc ; } !!else"
else if (Token::Match(tok2->next(), "if { dealloc|assign|use ; callfunc ; } !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(8));
done = false;
}
// Reducing if..
else if (_settings->_showAll)
{
if (Token::Match(tok2, "[;{}] if { assign|dealloc|use ; return ; } !!else"))
{
all = true;
Token::eraseTokens(tok2, tok2->tokAt(8));
done = false;
}
}
continue;
}
// Reduce "if(var) dealloc ;" and "if(var) use ;" that is not followed by an else..
if (Token::Match(tok2, "[;{}] if(var) assign|dealloc|use ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Reduce "; if(!var) alloc ; !!else" => "; dealloc ; alloc ;"
if (Token::Match(tok2, "; if(!var) alloc ; !!else"))
{
// Remove the "if(!var)"
Token::eraseTokens(tok2, tok2->tokAt(2));
// Insert "dealloc ;" before the "alloc ;"
tok2->insertToken(";");
tok2->insertToken("dealloc");
done = false;
}
// Remove "catch ;"
if (Token::simpleMatch(tok2->next(), "catch ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Reduce "if* ;" that is not followed by an else..
if (Token::Match(tok2->next(), "if(var)|if(!var)|ifv ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Reduce "else ;" => ";"
if (Token::simpleMatch(tok2->next(), "else ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Delete if block: "alloc; if return use ;"
if (Token::Match(tok2, "alloc ; if return use ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(5));
done = false;
}
// Replace "dealloc use ;" with "dealloc ;"
if (Token::simpleMatch(tok2, "dealloc use ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Remove the "if break|continue ;" that follows "dealloc ; alloc ;"
if (! _settings->_showAll && Token::Match(tok2, "dealloc ; alloc ; if break|continue ;"))
{
tok2 = tok2->tokAt(3);
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Reduce "do { alloc ; } " => "alloc ;"
// TODO: If the loop can be executed twice reduce to "loop alloc ;" instead
if (Token::simpleMatch(tok2->next(), "do { alloc ; }"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
Token::eraseTokens(tok2->tokAt(2), tok2->tokAt(4));
done = false;
}
// Reduce "loop if break ; => ";"
if (Token::Match(tok2->next(), "loop if break|continue ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Reduce "loop { assign|dealloc|use ; alloc ; if break ; }" to "assign|dealloc|use ; alloc ;"
if (Token::Match(tok2->next(), "loop { assign|dealloc|use ; alloc ; if break|continue ; }"))
{
// erase "loop {"
Token::eraseTokens(tok2, tok2->tokAt(3));
// erase "if break|continue ; }"
tok2 = tok2->tokAt(4);
Token::eraseTokens(tok2, tok2->tokAt(5));
done = false;
}
// Replace "loop { X ; break ; }" with "X ;"
if (Token::Match(tok2->next(), "loop { %var% ; break ; }"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
Token::eraseTokens(tok2->tokAt(2), tok2->tokAt(6));
done = false;
}
// Replace "loop ;" with ";"
if (Token::simpleMatch(tok2->next(), "loop ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Replace "loop !var ;" with ";"
if (Token::Match(tok2->next(), "loop !var ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Replace "loop !var alloc ;" with " alloc ;"
if (Token::Match(tok2->next(), "loop !var alloc ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Replace "loop if return ;" with "if return ;"
if (Token::simpleMatch(tok2->next(), "loop if return"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Delete if block in "alloc ; if(!var) return ;"
if (Token::Match(tok2, "alloc ; if(!var) return ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(4));
done = false;
}
// Delete if block: "alloc; if return use ;"
if (Token::Match(tok2, "alloc ; if return use ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(5));
done = false;
}
// Reduce "[;{}] return ; %var%" => "[;{}] return ;"
if (Token::Match(tok2, "[;{}] return ; %var%"))
{
Token::eraseTokens(tok2->tokAt(2), tok2->tokAt(4));
done = false;
}
// Reduce "[;{}] return use ; %var%" => "[;{}] return use ;"
if (Token::Match(tok2, "[;{}] return use ; %var%"))
{
Token::eraseTokens(tok2->tokAt(3), tok2->tokAt(5));
done = false;
}
// Reduce "if(var) return use ;" => "return use ;"
if (Token::Match(tok2->next(), "if(var) return use ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Reduce "if(var) assign|dealloc|use ;" => "assign|dealloc|use ;"
if (Token::Match(tok2->next(), "if(var) assign|dealloc|use ; !!else"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// malloc - realloc => alloc ; dealloc ; alloc ;
// Reduce "[;{}] alloc ; dealloc ; alloc ;" => "[;{}] alloc ;"
if (Token::Match(tok2, "[;{}] alloc ; dealloc ; alloc ;"))
{
Token::eraseTokens(tok2->next(), tok2->tokAt(6));
done = false;
}
// Delete second use in "use ; use ;"
while (Token::Match(tok2, "[;{}] use ; use ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Delete first part in "use ; dealloc ;"
if (Token::Match(tok2, "[;{}] use ; dealloc ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Delete first part in "use ; return use ;"
if (Token::Match(tok2, "[;{}] use ; return use ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(2));
done = false;
}
// Delete second case in "case ; case ;"
while (Token::simpleMatch(tok2, "case ; case ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Replace switch with if (if not complicated)
if (Token::simpleMatch(tok2, "switch {"))
{
// Right now, I just handle if there are a few case and perhaps a default.
bool valid = false;
bool incase = false;
for (const Token * _tok = tok2->tokAt(2); _tok; _tok = _tok->next())
{
if (_tok->str() == "{")
break;
else if (_tok->str() == "}")
{
valid = true;
break;
}
else if (strncmp(_tok->str().c_str(), "if", 2) == 0)
break;
else if (_tok->str() == "switch")
break;
else if (_tok->str() == "loop")
break;
else if (incase && Token::simpleMatch(_tok, "case"))
break;
incase |= Token::simpleMatch(_tok, "case");
incase &= !Token::simpleMatch(_tok, "break");
}
if (!incase && valid)
{
done = false;
tok2->str(";");
Token::eraseTokens(tok2, tok2->tokAt(2));
tok2 = tok2->next();
bool first = true;
while (Token::Match(tok2, "case|default"))
{
bool def = Token::simpleMatch(tok2, "default");
tok2->str(first ? "if" : "}");
if (first)
{
first = false;
tok2->insertToken("{");
}
else
{
// Insert "else [if] {
tok2->insertToken("{");
if (! def)
tok2->insertToken("if");
tok2->insertToken("else");
tok2 = tok2->next();
}
while (tok2 && tok2->str() != "}" && ! Token::simpleMatch(tok2, "break ;"))
tok2 = tok2->next();
if (Token::simpleMatch(tok2, "break ;"))
{
tok2->str(";");
tok2 = tok2->tokAt(2);
}
}
}
}
}
}
}
// Check for memory leaks for a function variable.
void CheckMemoryLeakInFunction::checkScope(const Token *Tok1, const char varname[], bool classmember, unsigned int sz)
{
std::list<const Token *> callstack;
AllocType alloctype = No;
AllocType dealloctype = No;
bool all = false;
const Token *result;
Token *tok = getcode(Tok1, callstack, varname, alloctype, dealloctype, classmember, all, sz);
//tok->printOut( "getcode result" );
// Simplify the code and check if freed memory is used..
for (Token *tok2 = tok; tok2; tok2 = tok2->next())
{
while (Token::Match(tok2, "[;{}] ;"))
Token::eraseTokens(tok2, tok2->tokAt(2));
}
if ((result = Token::findmatch(tok, "[;{}] dealloc [;{}] use|use_ ;")) != NULL)
{
deallocuseError(result->tokAt(3), varname);
}
// Replace "&use" with "use". Replace "use_" with ";"
for (Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "&use")
tok2->str("use");
else if (tok2->str() == "use_")
tok2->str(";");
else if (tok2->str() == "::use") // Some kind of member function usage. Not analyzed very well.
tok2->str("use");
else if (tok2->str() == "recursive")
tok2->str("use");
else if (tok2->str() == "dealloc_")
tok2->str("dealloc");
else if (tok2->str() == "realloc")
{
tok2->str("dealloc");
tok2->insertToken("alloc");
tok2->insertToken(";");
}
}
simplifycode(tok, all);
//tok->printOut("simplifycode result");
// If the variable is not allocated at all => no memory leak
if (Token::findmatch(tok, "alloc") == 0)
{
Tokenizer::deleteTokens(tok);
return;
}
// TODO : handle "goto"
if (Token::findmatch(tok, "goto"))
{
Tokenizer::deleteTokens(tok);
return;
}
if ((result = Token::findmatch(tok, "loop alloc ;")) != NULL)
{
MemoryLeak(result, varname, alloctype, all);
}
else if ((result = Token::findmatch(tok, "alloc ; if break|continue|return ;")) != NULL
&& Token::findmatch(tok, "dealloc ; alloc ; if continue ;") == NULL)
{
MemoryLeak(result->tokAt(3), varname, alloctype, all);
}
else if (_settings->_showAll && (result = Token::findmatch(tok, "alloc ; ifv break|continue|return ;")) != NULL)
{
MemoryLeak(result->tokAt(3), varname, alloctype, all);
}
else if ((result = Token::findmatch(tok, "alloc ; alloc|assign|return callfunc| ;")) != NULL)
{
MemoryLeak(result->tokAt(2), varname, alloctype, all);
}
else if ((result = Token::findmatch(tok, "dealloc ; dealloc ;")) != NULL)
{
deallocDeallocError(result->tokAt(2), varname);
}
else if (! Token::findmatch(tok, "dealloc") &&
! Token::findmatch(tok, "use") &&
! Token::findmatch(tok, "return use ;"))
{
const Token *last = tok;
while (last->next())
last = last->next();
MemoryLeak(last, varname, alloctype, all);
}
// detect cases that "simplifycode" don't handle well..
else if (_settings->_debug)
{
Token *first = tok;
while (first && first->str() == ";")
first = first->next();
bool noerr = false;
noerr |= Token::simpleMatch(first, "alloc ; }");
noerr |= Token::simpleMatch(first, "alloc ; dealloc ; }");
noerr |= Token::simpleMatch(first, "alloc ; return use ; }");
noerr |= Token::simpleMatch(first, "alloc ; use ; }");
noerr |= Token::simpleMatch(first, "alloc ; use ; return ; }");
noerr |= Token::simpleMatch(first, "if alloc ; dealloc ; }");
noerr |= Token::simpleMatch(first, "if alloc ; return use ; }");
noerr |= Token::simpleMatch(first, "if alloc ; use ; }");
noerr |= Token::simpleMatch(first, "alloc ; ifv return ; dealloc ; }");
noerr |= Token::simpleMatch(first, "alloc ; if return ; dealloc; }");
// Unhandled case..
if (! noerr)
{
std::cout << "Token listing..\n ";
for (const Token *tok2 = tok; tok2; tok2 = tok2->next())
std::cout << " " << tok2->str();
std::cout << "\n";
}
}
Tokenizer::deleteTokens(tok);
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// Checks for memory leaks inside function..
//---------------------------------------------------------------------------
void CheckMemoryLeakInFunction::check()
{
bool classmember = false;
bool beforeParameters = false;
bool infunc = false;
int indentlevel = 0;
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
--indentlevel;
// In function..
if (indentlevel == 0)
{
if (Token::simpleMatch(tok, ") {"))
infunc = true;
else if (tok->str() == "(")
beforeParameters = false;
else if (tok->str() == "::" && beforeParameters)
classmember = true;
else if (Token::Match(tok, "[;}]"))
{
infunc = classmember = false;
beforeParameters = true;
}
}
// Declare a local variable => Check
if (indentlevel > 0 && infunc)
{
unsigned int sz = _tokenizer->SizeOfType(tok->strAt(1));
if (sz < 1)
sz = 1;
if (Token::Match(tok, "[{};] %type% * const| %var% [;=]"))
{
const int varname_tok = (tok->tokAt(3)->str() != "const" ? 3 : 4);
checkScope(tok->next(), tok->strAt(varname_tok), classmember, sz);
}
else if (Token::Match(tok, "[{};] %type% %type% * const| %var% [;=]"))
{
const int varname_tok = (tok->tokAt(4)->str() != "const" ? 4 : 5);
checkScope(tok->next(), tok->strAt(varname_tok), classmember, sz);
}
}
}
}
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
// Checks for memory leaks in classes..
//---------------------------------------------------------------------------
void CheckMemoryLeakInClass::check()
{
int indentlevel = 0;
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
--indentlevel;
else if (indentlevel == 0 && Token::Match(tok, "class %var% [{:]"))
{
std::vector<const char *> classname;
classname.push_back(tok->strAt(1));
parseClass(tok, classname);
}
}
}
void CheckMemoryLeakInClass::parseClass(const Token *tok1, std::vector<const char *> &classname)
{
// Go into class.
while (tok1 && tok1->str() != "{")
tok1 = tok1->next();
if (tok1)
tok1 = tok1->next();
int indentlevel = 0;
for (const Token *tok = tok1; tok; tok = tok->next())
{
if (tok->str() == "{")
++indentlevel;
else if (tok->str() == "}")
{
--indentlevel;
if (indentlevel < 0)
return;
}
// Only parse this particular class.. not subclasses
if (indentlevel > 0)
continue;
// Declaring subclass.. recursive checking
if (Token::Match(tok, "class %var% [{:]"))
{
classname.push_back(tok->strAt(1));
parseClass(tok, classname);
classname.pop_back();
}
// Declaring member variable.. check allocations and deallocations
if (Token::Match(tok->next(), "%type% * %var% ;"))
{
// No false positives for auto deallocated classes..
if (_settings->isAutoDealloc(tok->strAt(1)))
continue;
if (tok->isName() || Token::Match(tok, "[;}]"))
{
if (_settings->_showAll || !isclass(_tokenizer, tok->tokAt(1)))
variable(classname.back(), tok->tokAt(3));
}
}
}
}
void CheckMemoryLeakInClass::variable(const char classname[], const Token *tokVarname)
{
const char *varname = tokVarname->strAt(0);
// Check if member variable has been allocated and deallocated..
CheckMemoryLeak::AllocType Alloc = CheckMemoryLeak::No;
CheckMemoryLeak::AllocType Dealloc = CheckMemoryLeak::No;
// Loop through all tokens. Inspect member functions
int indent_ = 0;
const Token *functionToken = Tokenizer::FindClassFunction(_tokenizer->tokens(), classname, "~| %var%", indent_);
while (functionToken)
{
int indent = 0;
bool initlist = false;
for (const Token *tok = functionToken; tok; tok = tok->next())
{
if (tok->str() == "{")
++indent;
else if (tok->str() == "}")
{
--indent;
if (indent <= 0)
break;
}
else if (indent == 0 && Token::simpleMatch(tok, ") :"))
initlist = true;
else if (initlist || indent > 0)
{
if (indent == 0)
{
if (!Token::Match(tok, (":|, " + std::string(varname) + " (").c_str()))
continue;
}
// Allocate..
if (indent == 0 || Token::Match(tok, (std::string(varname) + " =").c_str()))
{
AllocType alloc = GetAllocationType(tok->tokAt((indent > 0) ? 2 : 3));
if (alloc != CheckMemoryLeak::No)
{
if (Alloc != No && Alloc != alloc)
alloc = CheckMemoryLeak::Many;
std::list<const Token *> callstack;
if (alloc != CheckMemoryLeak::Many && Dealloc != CheckMemoryLeak::No && Dealloc != CheckMemoryLeak::Many && Dealloc != alloc)
{
callstack.push_back(tok);
mismatchAllocDealloc(callstack, (std::string(classname) + "::" + varname).c_str());
callstack.pop_back();
}
Alloc = alloc;
}
}
if (indent == 0)
continue;
// Deallocate..
const char *varnames[3] = { "var", 0, 0 };
varnames[0] = varname;
AllocType dealloc = GetDeallocationType(tok, varnames);
if (dealloc == No)
{
varnames[0] = "this";
varnames[1] = varname;
dealloc = GetDeallocationType(tok, varnames);
}
if (dealloc != CheckMemoryLeak::No)
{
if (Dealloc != CheckMemoryLeak::No && Dealloc != dealloc)
dealloc = CheckMemoryLeak::Many;
std::list<const Token *> callstack;
if (dealloc != CheckMemoryLeak::Many && Alloc != CheckMemoryLeak::No && Alloc != Many && Alloc != dealloc)
{
callstack.push_back(tok);
mismatchAllocDealloc(callstack, (std::string(classname) + "::" + varname).c_str());
callstack.pop_back();
}
Dealloc = dealloc;
}
}
}
functionToken = Tokenizer::FindClassFunction(functionToken->next(), classname, "~| %var%", indent_);
}
if (Alloc != CheckMemoryLeak::No && Dealloc == CheckMemoryLeak::No)
{
MemoryLeak(tokVarname, (std::string(classname) + "::" + varname).c_str(), Alloc, true);
}
}