cppcheck/src/checkmemoryleak.cpp

2288 lines
73 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 <cstdlib>
#include <iostream>
#include <sstream>
#include <set>
//---------------------------------------------------------------------------
// Register this check class (by creating a static instance of it)
namespace
{
CheckMemoryLeakInFunction instance1;
CheckMemoryLeakInClass instance2;
CheckMemoryLeakStructMember instance3;
}
// This list needs to be alphabetically sorted so we can run bsearch on it
static const char * const call_func_white_list[] =
{
"asprintf", "atof", "atoi", "atol", "clearerr", "delete", "fchmod", "fcntl"
, "fdatasync", "feof", "ferror", "fflush", "fgetc", "fgetpos", "fgets"
, "flock", "for", "fprintf", "fputc", "fputs", "fread", "free", "fseek"
, "fseeko", "fsetpos", "fstat", "fsync", "ftell", "ftello", "ftruncate"
, "fwrite", "getc", "if", "ioctl", "lockf", "lseek", "memchr", "memcpy"
, "memmove", "memset", "posix_fadvise", "posix_fallocate", "pread"
, "printf", "pwrite", "read", "readahead", "readdir", "readdir_r", "readv"
, "realloc", "return", "rewind", "rewinddir", "scandir", "seekdir"
, "setbuf", "setbuffer", "setlinebuf", "setvbuf", "snprintf", "sprintf", "strcasecmp"
, "strcat", "strchr", "strcmp", "strcpy", "stricmp", "strncat", "strncmp"
, "strncpy", "strrchr", "strstr", "strtod", "strtol", "strtoul", "switch"
, "sync_file_range", "telldir", "while", "write", "writev"
};
static int call_func_white_list_compare(const void *a, const void *b)
{
return strcmp((const char *)a, *(const char **)b);
}
//---------------------------------------------------------------------------
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, unsigned int varid) const
{
// What we may have...
// * var = (char *)malloc(10);
// * var = new char[10];
// * var = strdup("hello");
// * var = strndup("hello", 3);
if (tok2 && tok2->str() == "(")
{
tok2 = tok2->link();
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;
}
// Using realloc..
if (varid && Token::Match(tok2, "realloc ( %any% ,") && tok2->tokAt(2)->varId() != varid)
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::Match(tok2, "open|openat|creat|mkstemp|mkostemp ("))
return Fd;
if (Token::simpleMatch(tok2, "popen ("))
return Pipe;
if (Token::Match(tok2, "opendir|fdopendir ("))
return Dir;
return No;
}
CheckMemoryLeak::AllocType CheckMemoryLeak::getReallocationType(const Token *tok2, unsigned int varid) const
{
// What we may have...
// * var = (char *)realloc(..;
if (tok2 && tok2->str() == "(")
{
tok2 = tok2->link();
tok2 = tok2 ? tok2->next() : NULL;
}
if (! tok2)
return No;
if (! Token::Match(tok2, "%var% ( %varid% [,)]", varid))
return No;
if (tok2->str() == "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, unsigned int varid) const
{
if (Token::Match(tok, "delete %varid% ;", varid))
return New;
if (Token::Match(tok, "delete [ ] %varid% ;", varid))
return NewArray;
if (Token::Match(tok, "delete ( %varid% ) ;", varid))
return New;
if (Token::Match(tok, "delete [ ] ( %varid% ) ;", varid))
return NewArray;
if (Token::Match(tok, "free ( %varid% ) ;", varid) ||
Token::Match(tok, "kfree ( %varid% ) ;", varid))
return Malloc;
if (Token::Match(tok, "g_free ( %varid% ) ;", varid))
return gMalloc;
if (Token::Match(tok, "fclose ( %varid% )", varid) ||
Token::Match(tok, "fcloseall ( )"))
return File;
if (Token::Match(tok, "close ( %varid% )", varid))
return Fd;
if (Token::Match(tok, "pclose ( %varid% )", varid))
return Pipe;
if (Token::Match(tok, "closedir ( %varid% )", varid))
return Dir;
return No;
}
CheckMemoryLeak::AllocType CheckMemoryLeak::getDeallocationType(const Token *tok, const char *varnames[]) const
{
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("close ( " + names + " )").c_str()))
return Fd;
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 std::string &varname, AllocType alloctype, bool all)
{
if (alloctype == CheckMemoryLeak::File ||
alloctype == CheckMemoryLeak::Pipe ||
alloctype == CheckMemoryLeak::Fd ||
alloctype == CheckMemoryLeak::Dir)
resourceLeakError(tok, varname.c_str(), all);
else
memleakError(tok, varname.c_str(), all);
}
//---------------------------------------------------------------------------
void CheckMemoryLeak::reportErr(const Token *tok, Severity::e severity, const std::string &id, const std::string &msg) const
{
std::list<const Token *> callstack;
if (tok)
callstack.push_back(tok);
reportErr(callstack, severity, id, msg);
}
void CheckMemoryLeak::reportErr(const std::list<const Token *> &callstack, Severity::e severity, const std::string &id, const std::string &msg) const
{
std::list<ErrorLogger::ErrorMessage::FileLocation> locations;
for (std::list<const Token *>::const_iterator it = callstack.begin(); it != callstack.end(); ++it)
{
ErrorLogger::ErrorMessage::FileLocation loc;
loc.line = (*it)->linenr();
loc.file = tokenizer->file(*it);
locations.push_back(loc);
}
const ErrorLogger::ErrorMessage errmsg(locations, Severity::stringify(severity), msg, id);
if (errorLogger)
errorLogger->reportErr(errmsg);
else
std::cout << errmsg.toXML() << std::endl;
}
void CheckMemoryLeak::memleakError(const Token *tok, const std::string &varname, bool all)
{
reportErr(tok, all ? Severity::possibleError : Severity::error, "memleak", "Memory leak: " + varname);
}
void CheckMemoryLeak::resourceLeakError(const Token *tok, const std::string &varname, bool all)
{
reportErr(tok, all ? Severity::possibleError : Severity::error, "resourceLeak", "Resource leak: " + varname);
}
void CheckMemoryLeak::deallocDeallocError(const Token *tok, const std::string &varname)
{
reportErr(tok, Severity::error, "deallocDealloc", "Deallocating a deallocated pointer: " + varname);
}
void CheckMemoryLeak::deallocuseError(const Token *tok, const std::string &varname)
{
reportErr(tok, Severity::error, "deallocuse", "Dereferencing '" + varname + "' after it is deallocated / released");
}
void CheckMemoryLeak::mismatchSizeError(const Token *tok, const std::string &sz)
{
reportErr(tok, Severity::error, "mismatchSize", "The given size " + sz + " is mismatching");
}
void CheckMemoryLeak::mismatchAllocDealloc(const std::list<const Token *> &callstack, const std::string &varname)
{
reportErr(callstack, Severity::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..
unsigned int varid = 0;
AllocType allocType = No;
while (tok)
{
// variable declaration..
if (Token::Match(tok, "%type% * %var% ;"))
{
tok = tok->tokAt(4);
continue;
}
if (varid == 0 && tok->varId() && Token::Match(tok, "%var% ="))
{
varid = tok->varId();
allocType = getAllocationType(tok->tokAt(2), varid);
if (allocType == No)
return No;
while (tok && tok->str() != ";")
tok = tok->next();
tok = tok ? tok->next() : 0;
continue;
}
if (tok->str() == "return")
{
if (varid > 0 && Token::Match(tok->next(), "%varid% ;", varid))
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, unsigned int varid) const
{
return Token::Match(tok, "; %varid% = strcat|memcpy|memmove|strcpy ( %varid% ,", varid);
}
bool CheckMemoryLeakInFunction::notvar(const Token *tok, unsigned int varid, bool endpar) const
{
const std::string end(endpar ? " &&|)" : " [;)&|]");
return bool(Token::Match(tok, ("! %varid%" + end).c_str(), varid) ||
Token::Match(tok, ("! ( %varid% )" + end).c_str(), varid));
}
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, unsigned int varid, AllocType &alloctype, AllocType &dealloctype, bool &all, unsigned int sz)
{
if (std::bsearch(tok->strAt(0), call_func_white_list,
sizeof(call_func_white_list) / sizeof(call_func_white_list[0]),
sizeof(call_func_white_list[0]), call_func_white_list_compare))
return 0;
if (getAllocationType(tok, varid) != No || getReallocationType(tok, varid) != No || getDeallocationType(tok, varid) != 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;
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, "[,()] %varid% [,()]", varid))
{
const Token *ftok = _tokenizer->getFunctionTokenByName(funcname.c_str());
if (!ftok)
return "use";
// how many parameters does the function want?
if (numpar != countParameters(ftok))
return "recursive";
const char *parname = Tokenizer::getParameterName(ftok, par);
if (! parname)
return "recursive";
unsigned int parameterVarid = 0;
{
const Token *partok = Token::findmatch(ftok, parname);
if (partok)
parameterVarid = partok->varId();
}
if (parameterVarid == 0)
return "recursive";
// Check if the function deallocates the variable..
while (ftok && (ftok->str() != "{"))
ftok = ftok->next();
Token *func = getcode(ftok->tokAt(1), callstack, parameterVarid, alloctype, dealloctype, false, all, sz);
simplifycode(func, all);
const Token *func_ = func;
while (func_ && func_->str() == ";")
func_ = func_->next();
const char *ret = 0;
/** @todo handle "goto" */
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, unsigned int varid, AllocType &alloctype, AllocType &dealloctype, bool classmember, bool &all, unsigned int sz)
{
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(";");
// var = strcpy|.. ( var ,
if (Token::Match(tok, "[;{}] %varid% = memcpy|memmove|memset|strcpy|strncpy|strcat|strncat ( %varid% ,", varid))
{
tok = tok->tokAt(4)->link();
continue;
}
if (Token::Match(tok->previous(), "[(;{}] %varid% =", varid) ||
Token::Match(tok, "asprintf ( & %varid% ,", varid))
{
AllocType alloc;
if (Token::simpleMatch(tok, "asprintf ("))
{
// todo: check how the return value is used.
if (!Token::Match(tok->previous(), "[;{}]"))
{
Tokenizer::deleteTokens(rethead);
return 0;
}
alloc = Malloc;
tok = tok->next()->link();
}
else
{
alloc = getAllocationType(tok->tokAt(2), varid);
}
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), varid);
if (alloc != No)
{
addtoken("realloc");
addtoken(";");
realloc = true;
tok = tok->tokAt(2);
continue;
}
}
// 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, Token::findmatch(_tokenizer->tokens(), "%varid%", varid)->str());
callstack.pop_back();
}
alloctype = alloc;
}
else if (matchFunctionsThatReturnArg(tok->previous(), varid))
{
addtoken("use");
}
// assignment..
else
{
// is the pointer in rhs?
bool rhs = false;
for (const Token *tok2 = tok; tok2; tok2 = tok2->next())
{
if (tok2->str() == ";")
break;
if (Token::Match(tok2, "[=+] %varid%", varid))
{
rhs = true;
break;
}
}
addtoken((rhs ? "use" : "assign"));
}
}
if (Token::Match(tok->previous(), "[;{})=] %var%"))
{
AllocType dealloc = getDeallocationType(tok, varid);
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, Token::findmatch(_tokenizer->tokens(), "%varid%", varid)->str());
callstack.pop_back();
}
dealloctype = dealloc;
continue;
}
}
// if else switch
if (tok->str() == "if")
{
if (alloctype == Fd)
{
if (Token::Match(tok, "if ( %varid% >= 0 )", varid) ||
Token::Match(tok, "if ( %varid% != -1 )", varid))
{
addtoken("if(var)");
tok = tok->next()->link();
continue;
}
else if (Token::Match(tok, "if ( %varid% == -1 )", varid) ||
Token::Match(tok, "if ( %varid% < 0 )", varid))
{
addtoken("if(!var)");
tok = tok->next()->link();
continue;
}
}
if (Token::Match(tok, "if ( %varid% )", varid))
{
addtoken("if(var)");
// Make sure the "use" will not be added
tok = tok->next()->link();
}
else if (Token::simpleMatch(tok, "if (") && notvar(tok->tokAt(2), varid, 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, "close|fclose|closedir ( %varid% )", varid))
{
addtoken("dealloc");
addtoken(";");
dep = true;
break;
}
if (Token::Match(tok2, ". %varid% !!.", varid))
{
dep = true;
break;
}
if (alloctype == Fd && Token::Match(tok2, "%varid% !=|>=", varid))
{
dep = true;
}
}
if (Token::Match(tok, "if ( ! %varid% &&", varid))
{
addtoken("if(!var)");
}
else if (tok->next() &&
tok->next()->link() &&
Token::Match(tok->next()->link()->tokAt(-3), "&& ! %varid%", varid))
{
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, varid))
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::Match(tok2, "> ( %varid% )", varid))
{
addtoken("use");
tok = tok2->tokAt(3);
}
}
else if (varid && Token::Match(tok, "return &| %varid%", varid))
{
addtoken("use");
}
else if (varid && Token::Match(tok, "return strcpy|strncpy|memcpy ( %varid%", varid))
{
addtoken("use");
tok = tok->tokAt(2);
}
else
{
for (const Token *tok2 = tok->next(); tok2; tok2 = tok2->next())
{
if (tok2->str() == ";")
break;
if (tok2->varId() == varid)
{
addtoken("use");
tok = tok2;
break;
}
}
}
}
// throw..
else if (Token::Match(tok, "try|throw|catch"))
addtoken(tok->strAt(0));
// exit..
if (Token::Match(tok->previous(), "[{};] exit|_exit|_Exit ( %any% ) ;"))
{
addtoken("exit");
tok = tok->tokAt(3);
}
else if (Token::simpleMatch(tok, "abort ( ) ;"))
{
addtoken("exit");
tok = tok->tokAt(2);
}
else if (Token::Match(tok, "err|verr|errx|verrx ("))
{
addtoken("exit");
while (tok->next() && tok->next()->str() != ";")
{
tok = tok->next();
}
}
// Assignment..
if (varid)
{
if (Token::Match(tok, "[)=] %varid% [+;)]", varid) ||
Token::Match(tok, "%varid% +=|-=", varid) ||
Token::Match(tok, "+=|<< %varid% ;", varid) ||
Token::Match(tok, "= strcpy|strcat|memmove|memcpy ( %varid% ,", varid))
{
addtoken("use");
}
else if (Token::Match(tok->previous(), "[;{}=(,+-*/] %varid% [", varid))
{
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->varId() == varid)
{
addtoken("::use");
break;
}
}
}
else
{
const char *str = call_func(tok, callstack, varid, alloctype, dealloctype, all, sz);
if (str)
{
if (Token::Match(tok->tokAt(-2), "%varid% =", varid) || std::string(str) != "alloc")
addtoken(str);
}
else
{
if (getReallocationType(tok, varid) != No &&
tok->tokAt(2)->varId() == varid)
{
addtoken("if");
addtoken("{");
addtoken("dealloc");
addtoken(";");
addtoken("}");
tok = tok->tokAt(2);
continue;
}
}
}
}
// Callback..
bool matchFirst = Token::Match(tok, "( %var%");
if (matchFirst || Token::Match(tok, "( * %var%"))
{
int tokIdx = matchFirst ? 2 : 3;
while (Token::Match(tok->tokAt(tokIdx), ". %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->varId() == varid)
{
addtoken("use");
break;
}
}
}
}
// Linux lists..
if (Token::Match(tok, "[=(,] & %varid% [.[,)]", varid))
{
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");
}
// If "--all" is given, remove all "callfunc"..
if (_settings->_showAll)
{
Token *tok2 = tok;
while (tok2)
{
if (tok2->str() == "callfunc")
{
tok2->deleteThis();
all = true;
}
else
tok2 = tok2->next();
}
}
// reduce the code..
bool done = false;
while (! done)
{
//tok->printOut("simplifycode loop..");
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 (tok2->next() && tok2->next()->str() == "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;
}
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|return ;"))
{
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" => "if"
else if (Token::simpleMatch(tok2->next(), "if ; else"))
{
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 "if { dealloc|assign|use ; return ; }"
else if (Token::Match(tok2, "[;{}] if { dealloc|assign|use ; return ; }"))
{
Token::eraseTokens(tok2, tok2->tokAt(8));
done = false;
}
// Remove "if { dealloc ; callfunc ; } !!else"
else if (Token::Match(tok2->next(), "if { dealloc|assign ; 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;
}
// Reduce "; if(!var) exit ;" => ";"
if (Token::Match(tok2, "; if(!var) exit ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Reduce "} else .." => "} if .."
if (Token::simpleMatch(tok2, "} else"))
{
int indentlevel = 0;
for (const Token *tok3 = tok2; tok3; tok3 = tok3->previous())
{
if (tok3->str() == "{")
{
--indentlevel;
if (indentlevel == 0)
{
if (tok3->previous()->str() == "if")
tok2->next()->str("if");
}
if (indentlevel <= 0)
break;
}
else if (tok3->str() == "}")
{
++indentlevel;
}
}
}
// Remove "catch ;"
if (Token::simpleMatch(tok2->next(), "catch ;"))
{
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Reduce "if* ;"..
if (Token::Match(tok2->next(), "if(var)|if(!var)|ifv ;"))
{
// Followed by else..
if (Token::simpleMatch(tok2->tokAt(3), "else"))
{
tok2 = tok2->next();
if (tok2->str() == "if(var)")
tok2->str("if(!var)");
else if (tok2->str() == "if(!var)")
tok2->str("if(var)");
// remove the "; else"
Token::eraseTokens(tok2, tok2->tokAt(3));
}
else
{
// remove the "if* ;"
Token::eraseTokens(tok2, tok2->tokAt(3));
}
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;
}
// Reduce "alloc|dealloc|use ; exit ;" => "; exit ;"
if (Token::Match(tok2, "alloc|dealloc|use|callfunc ; exit ;"))
{
tok2->deleteThis();
done = false;
}
// Reduce "alloc|dealloc|use ; if(var) exit ;"
if (Token::Match(tok2, "alloc|dealloc|use ; if(var) exit ;"))
{
tok2->deleteThis();
done = false;
}
// Remove "if exit ;"
if (Token::simpleMatch(tok2, "if exit ;"))
{
tok2->deleteThis();
tok2->deleteThis();
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 "do { alloc ; }" can be executed twice, reduce it to "loop alloc ;" */
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 "do ; loop ;" with ";"
if (Token::Match(tok2->next(), "%any% ; loop ;"))
{
if (tok2->next()->str() == "do")
tok2->deleteNext();
else
tok2 = tok2->next();
Token::eraseTokens(tok2, tok2->tokAt(3));
done = false;
}
// Replace "do ; loop !var ;" with ";"
if (Token::Match(tok2->next(), "%any% ; loop !var ;"))
{
if (tok2->next()->str() == "do")
tok2->deleteNext();
else
tok2 = tok2->next();
Token::eraseTokens(tok2, tok2->tokAt(4));
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 "callfunc ;" that is followed by "use|if|callfunc"
// If the function doesn't throw exception or exit the application, then the "callfunc" is not needed
if (Token::Match(tok2, "callfunc ; use|if|callfunc"))
{
tok2->deleteThis();
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 && _tok->str() == "case")
break;
incase |= (_tok->str() == "case");
incase &= (_tok->str() != "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(tok2->str() == "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);
}
}
}
}
}
}
}
const Token *CheckMemoryLeakInFunction::findleak(const Token *tokens, bool all)
{
const Token *result = 0;
// No allocation at all => no leaks
if (Token::findmatch(tokens, "alloc") == 0)
{
return NULL;
}
if ((result = Token::findmatch(tokens, "loop alloc ;")) != NULL)
{
return result;
}
if ((result = Token::findmatch(tokens, "alloc ; if break|continue|return ;")) != NULL
&& Token::findmatch(tokens, "dealloc ; alloc ; if continue ;") == NULL)
{
return result->tokAt(3);
}
if (all && (result = Token::findmatch(tokens, "alloc ; ifv break|continue|return ;")) != NULL)
{
return result->tokAt(3);
}
if ((result = Token::findmatch(tokens, "alloc ; alloc|assign|return callfunc| ;")) != NULL)
{
return result->tokAt(2);
}
if ((result = Token::findmatch(tokens, "alloc ; if assign ;")) != NULL)
{
return result->tokAt(3);
}
if ((result = Token::findmatch(tokens, "alloc ; }")) != NULL)
{
if (result->tokAt(3) == NULL)
return result->tokAt(2);
}
// No deallocation / usage => report leak at the last token
if (!Token::findmatch(tokens, "dealloc|use"))
{
const Token *last = tokens;
while (last->next())
last = last->next();
return last;
}
return NULL;
}
// Check for memory leaks for a function variable.
void CheckMemoryLeakInFunction::checkScope(const Token *Tok1, const std::string &varname, unsigned int varid, 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, varid, alloctype, dealloctype, classmember, all, sz);
//tok->printOut((std::string("Checkmemoryleak: getcode result for: ") + varname).c_str());
// 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_ ;")) != 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);
if (_settings->_debug && _settings->_verbose)
{
tok->printOut(("Checkmemoryleak: simplifycode result for: " + varname).c_str());
}
// 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 = findleak(tok, _settings->_showAll)) != NULL)
{
memoryLeak(result, varname, alloctype, all);
}
else if ((result = Token::findmatch(tok, "dealloc ; dealloc ;")) != NULL)
{
deallocDeallocError(result->tokAt(2), varname);
}
// 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;
// Skip these weird blocks... "( { ... } )"
else if (Token::simpleMatch(tok, "( {"))
{
tok = tok->link();
if (!tok)
break;
continue;
}
// 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%"))
continue;
// Don't check static variables
if (tok->next()->str() == "static")
continue;
// return/else is not part of a variable declaration..
if (Token::Match(tok->next(), "return|else"))
continue;
if (Token::Match(tok, "[{};] %type% * const| %var% [;=]"))
{
const Token *vartok = tok->tokAt(tok->tokAt(3)->str() != "const" ? 3 : 4);
checkScope(tok->next(), vartok->str(), vartok->varId(), classmember, sz);
}
else if (Token::Match(tok, "[{};] %type% %type% * const| %var% [;=]"))
{
const Token *vartok = tok->tokAt(tok->tokAt(4)->str() != "const" ? 4 : 5);
checkScope(tok->next(), vartok->str(), vartok->varId(), classmember, sz);
}
else if (Token::Match(tok, "[{};] int %var% [;=]"))
{
const Token *vartok = tok->tokAt(2);
checkScope(tok->next(), vartok->str(), vartok->varId(), 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)
{
if (!_settings->_showAll)
return;
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), 0);
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);
}
}
void CheckMemoryLeakStructMember::check()
{
// This should be in the CheckMemoryLeak base class
std::set<std::string> ignoredFunctions;
ignoredFunctions.insert("if");
ignoredFunctions.insert("for");
ignoredFunctions.insert("while");
ignoredFunctions.insert("malloc");
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
{
// Locate struct variables..
if (Token::Match(tok, "struct|;|{|} %type% * %var% [=;]"))
{
const Token * const vartok = tok->tokAt(3);
if (vartok->varId() == 0)
continue;
// Check that struct is allocated..
{
const unsigned int varid(vartok->varId());
bool alloc = false;
unsigned int indentlevel2 = 0;
for (const Token *tok2 = vartok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "{")
++indentlevel2;
else if (tok2->str() == "}")
{
if (indentlevel2 == 0)
break;
--indentlevel2;
}
else if (Token::Match(tok2, "= %varid% [;=]", varid))
{
alloc = false;
break;
}
else if (Token::Match(tok2, "%varid% = malloc|kmalloc (", varid))
{
alloc = true;
}
}
if (!alloc)
continue;
}
// Check struct..
unsigned int indentlevel2 = 0;
for (const Token *tok2 = vartok; tok2; tok2 = tok2->next())
{
if (tok2->str() == "{")
++indentlevel2;
else if (tok2->str() == "}")
{
if (indentlevel2 == 0)
break;
--indentlevel2;
}
// Unknown usage of struct
/** @todo Check how the struct is used. Only bail out if necessary */
else if (Token::Match(tok2, "[(,] %varid% [,)]", vartok->varId()))
break;
// Struct member is allocated => check if it is also properly deallocated..
else if (Token::Match(tok2, "%varid% . %var% = malloc|strdup|kmalloc (", vartok->varId()))
{
const unsigned int structid(vartok->varId());
const unsigned int structmemberid(tok2->tokAt(2)->varId());
// This struct member is allocated.. check that it is deallocated
unsigned int indentlevel3 = indentlevel2;
for (const Token *tok3 = tok2; tok3; tok3 = tok3->next())
{
if (tok3->str() == "{")
++indentlevel3;
else if (tok3->str() == "}")
{
if (indentlevel3 == 0)
{
memoryLeak(tok3, (vartok->str() + "." + tok2->strAt(2)).c_str(), Malloc, false);
break;
}
--indentlevel3;
}
// Deallocating the struct member..
else if (Token::Match(tok3, "free|kfree ( %var% . %varid% )", structmemberid))
{
// If the deallocation happens at the base level, don't check this member anymore
if (indentlevel3 == 0)
break;
// deallocating and then returning from function in a conditional block =>
// skip ahead out of the block
bool ret = false;
while (tok3)
{
// debug info
const std::string tok3str_(tok3->str());
if (tok3->str() == "return")
ret = true;
else if (tok3->str() == "{" || tok3->str() == "}")
break;
tok3 = tok3->next();
}
if (!ret || !tok3 || tok3->str() != "}")
break;
--indentlevel3;
continue;
}
// Deallocating the struct..
else if (indentlevel2 == 0 && Token::Match(tok3, "free|kfree ( %varid% )", structid))
{
memoryLeak(tok3, (vartok->str() + "." + tok2->strAt(2)).c_str(), Malloc, false);
break;
}
// failed allocation => skip code..
else if (Token::Match(tok3, "if ( ! %var% . %varid% )", structmemberid))
{
// Goto the ")"
tok3 = tok3->next()->link();
// make sure we have ") {".. it should be
if (!Token::simpleMatch(tok3, ") {"))
break;
// Goto the "}"
tok3 = tok3->next()->link();
}
// Returning from function..
else if (tok3->str() == "return")
{
// Returning from function without deallocating struct member?
if (!Token::Match(tok3, "return %varid% ;", structid))
{
memoryLeak(tok3, (vartok->str() + "." + tok2->strAt(2)).c_str(), Malloc, false);
}
break;
}
// goto isn't handled well.. bail out even though there might be leaks
else if (tok3->str() == "goto")
break;
// using struct in a function call..
else if (Token::Match(tok3, "%var% ("))
{
// Calling non-function / function that doesn't deallocate?
if (ignoredFunctions.find(tok3->str()) != ignoredFunctions.end())
continue;
// Check if the struct is used..
bool deallocated = false;
unsigned int parlevel = 0;
for (const Token *tok4 = tok3; tok4; tok4 = tok4->next())
{
if (tok4->str() == "(")
++parlevel;
else if (tok4->str() == ")")
{
if (parlevel <= 1)
break;
--parlevel;
}
if (Token::Match(tok4, "[(,] %varid% [,)]", structid))
{
/** @todo check if the function deallocates the memory */
deallocated = true;
break;
}
}
if (deallocated)
break;
}
}
}
}
}
}
}