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2758 lines (2350 loc) · 106 KB
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/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2016 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 "symboldatabase.h"
#include "mathlib.h"
#include "tokenize.h"
#include "astutils.h"
#include "utils.h"
#include <algorithm>
#include <set>
#include <stack>
//---------------------------------------------------------------------------
// Register this check class (by creating a static instance of it)
namespace {
CheckMemoryLeakInFunction instance1;
CheckMemoryLeakInClass instance2;
CheckMemoryLeakStructMember instance3;
CheckMemoryLeakNoVar instance4;
}
// CWE ID used:
static const CWE CWE398(398U); // Indicator of Poor Code Quality
static const CWE CWE401(401U); // Improper Release of Memory Before Removing Last Reference ('Memory Leak')
static const CWE CWE771(771U); // Missing Reference to Active Allocated Resource
static const CWE CWE772(772U); // Missing Release of Resource after Effective Lifetime
/**
* Count function parameters
* \param tok Function name token before the '('
*/
static unsigned int countParameters(const Token *tok)
{
tok = tok->tokAt(2);
if (tok->str() == ")")
return 0;
unsigned int numpar = 1;
while (nullptr != (tok = tok->nextArgument()))
numpar++;
return numpar;
}
/** List of functions that can be ignored when searching for memory leaks.
* These functions don't take the address of the given pointer
* This list contains function names with const parameters e.g.: atof(const char *)
* TODO: This list should be replaced by <leak-ignore/> in .cfg files.
*/
static const std::set<std::string> call_func_white_list = make_container < std::set<std::string> > ()
<< "_open" << "_wopen" << "access" << "adjtime" << "asctime_r" << "asprintf" << "chdir" << "chmod" << "chown"
<< "creat" << "ctime_r" << "execl" << "execle" << "execlp" << "execv" << "execve" << "fchmod" << "fcntl"
<< "fdatasync" << "fclose" << "flock" << "fmemopen" << "fnmatch" << "fopen" << "fopencookie" << "for" << "free"
<< "freopen"<< "fseeko" << "fstat" << "fsync" << "ftello" << "ftruncate" << "getgrnam" << "gethostbyaddr" << "gethostbyname"
<< "getnetbyname" << "getopt" << "getopt_long" << "getprotobyname" << "getpwnam" << "getservbyname" << "getservbyport"
<< "glob" << "gmtime" << "gmtime_r" << "if" << "index" << "inet_addr" << "inet_aton" << "inet_network" << "initgroups"
<< "ioctl" << "link" << "localtime_r" << "lockf" << "lseek" << "lstat" << "mkdir" << "mkfifo" << "mknod" << "mkstemp"
<< "obstack_printf" << "obstack_vprintf" << "open" << "opendir" << "parse_printf_format" << "pathconf"
<< "perror" << "popen" << "posix_fadvise" << "posix_fallocate" << "pread" << "psignal" << "pwrite" << "read" << "readahead"
<< "readdir" << "readdir_r" << "readlink" << "readv" << "realloc" << "regcomp" << "return" << "rewinddir" << "rindex"
<< "rmdir" << "scandir" << "seekdir" << "setbuffer" << "sethostname" << "setlinebuf" << "sizeof" << "strdup"
<< "stat" << "stpcpy" << "strcasecmp" << "stricmp" << "strncasecmp" << "switch"
<< "symlink" << "sync_file_range" << "telldir" << "tempnam" << "time" << "typeid" << "unlink"
<< "utime" << "utimes" << "vasprintf" << "while" << "wordexp" << "write" << "writev";
//---------------------------------------------------------------------------
bool CheckMemoryLeak::isclass(const Token *tok, unsigned int varid) const
{
if (tok->isStandardType())
return false;
const Variable * var = tokenizer->getSymbolDatabase()->getVariableFromVarId(varid);
// return false if the type is a simple record type without side effects
// a type that has no side effects (no constructors and no members with constructors)
/** @todo false negative: check base class for side effects */
/** @todo false negative: check constructors for side effects */
if (var && var->typeScope() && var->typeScope()->numConstructors == 0 &&
(var->typeScope()->varlist.empty() || var->type()->needInitialization == Type::True) &&
var->type()->derivedFrom.empty())
return false;
return true;
}
//---------------------------------------------------------------------------
CheckMemoryLeak::AllocType CheckMemoryLeak::getAllocationType(const Token *tok2, unsigned int varid, std::list<const Function*> *callstack) 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() : nullptr;
}
if (! tok2)
return No;
if (tok2->str() == "::")
tok2 = tok2->next();
if (! tok2->isName())
return No;
if (!Token::Match(tok2, "%name% ::|. %type%")) {
// Using realloc..
if (varid && Token::Match(tok2, "realloc ( %any% ,") && tok2->tokAt(2)->varId() != varid)
return Malloc;
if (tokenizer->isCPP() && tok2->str() == "new") {
if (tok2->strAt(1) == "(" && !Token::Match(tok2->next(),"( std| ::| nothrow )"))
return No;
if (tok2->astOperand1() && (tok2->astOperand1()->str() == "[" || (tok2->astOperand1()->astOperand1() && tok2->astOperand1()->astOperand1()->str() == "[")))
return NewArray;
return New;
}
if (settings1->standards.posix) {
if (Token::Match(tok2, "open|openat|creat|mkstemp|mkostemp|socket (")) {
// simple sanity check of function parameters..
// TODO: Make such check for all these functions
unsigned int num = countParameters(tok2);
if (tok2->str() == "open" && num != 2 && num != 3)
return No;
// is there a user function with this name?
if (tok2->function())
return No;
return Fd;
}
if (Token::simpleMatch(tok2, "popen ("))
return Pipe;
}
// Does tok2 point on a Library allocation function?
const int alloctype = settings1->library.alloc(tok2, -1);
if (alloctype > 0) {
if (alloctype == settings1->library.deallocId("free"))
return Malloc;
if (alloctype == settings1->library.deallocId("fclose"))
return File;
return Library::ismemory(alloctype) ? OtherMem : OtherRes;
}
}
while (Token::Match(tok2,"%name% ::|. %type%"))
tok2 = tok2->tokAt(2);
// User function
const Function* func = tok2->function();
if (func == nullptr)
return No;
// Prevent recursion
if (callstack && std::find(callstack->begin(), callstack->end(), func) != callstack->end())
return No;
std::list<const Function*> cs;
if (!callstack)
callstack = &cs;
callstack->push_back(func);
return functionReturnType(func, callstack);
}
CheckMemoryLeak::AllocType CheckMemoryLeak::getReallocationType(const Token *tok2, unsigned int varid)
{
// What we may have...
// * var = (char *)realloc(..;
if (tok2 && tok2->str() == "(") {
tok2 = tok2->link();
tok2 = tok2 ? tok2->next() : nullptr;
}
if (! tok2)
return No;
if (varid > 0 && ! Token::Match(tok2, "%name% ( %varid% [,)]", varid))
return No;
if (tok2->str() == "realloc")
return Malloc;
return No;
}
CheckMemoryLeak::AllocType CheckMemoryLeak::getDeallocationType(const Token *tok, unsigned int varid) const
{
if (tokenizer->isCPP() && tok->str() == "delete" && tok->astOperand1()) {
const Token* vartok = tok->astOperand1();
if (Token::Match(vartok, ".|::"))
vartok = vartok->astOperand2();
if (vartok && vartok->varId() == varid) {
if (tok->strAt(1) == "[")
return NewArray;
return New;
}
}
if (tok->str() == "::")
tok = tok->next();
if (Token::Match(tok, "%name% (")) {
if (Token::simpleMatch(tok, "fcloseall ( )"))
return File;
int argNr = 1;
for (const Token* tok2 = tok->tokAt(2); tok2; tok2 = tok2->nextArgument()) {
const Token* vartok = tok2;
while (Token::Match(vartok, "%name% .|::"))
vartok = vartok->tokAt(2);
if (Token::Match(vartok, "%varid% )|,|-", varid)) {
if (tok->str() == "realloc" && Token::simpleMatch(vartok->next(), ", 0 )"))
return Malloc;
if (settings1->standards.posix) {
if (tok->str() == "close")
return Fd;
if (tok->str() == "pclose")
return Pipe;
}
// Does tok point on a Library deallocation function?
const int dealloctype = settings1->library.dealloc(tok, argNr);
if (dealloctype > 0) {
if (dealloctype == settings1->library.deallocId("free"))
return Malloc;
if (dealloctype == settings1->library.deallocId("fclose"))
return File;
return Library::ismemory(dealloctype) ? OtherMem : OtherRes;
}
}
argNr++;
}
}
return No;
}
//--------------------------------------------------------------------------
//--------------------------------------------------------------------------
void CheckMemoryLeak::memoryLeak(const Token *tok, const std::string &varname, AllocType alloctype)
{
if (alloctype == CheckMemoryLeak::File ||
alloctype == CheckMemoryLeak::Pipe ||
alloctype == CheckMemoryLeak::Fd ||
alloctype == CheckMemoryLeak::OtherRes)
resourceLeakError(tok, varname);
else
memleakError(tok, varname);
}
//---------------------------------------------------------------------------
void CheckMemoryLeak::reportErr(const Token *tok, Severity::SeverityType severity, const std::string &id, const std::string &msg, const CWE &cwe) const
{
std::list<const Token *> callstack;
if (tok)
callstack.push_back(tok);
reportErr(callstack, severity, id, msg, cwe);
}
void CheckMemoryLeak::reportErr(const std::list<const Token *> &callstack, Severity::SeverityType severity, const std::string &id, const std::string &msg, const CWE &cwe) const
{
const ErrorLogger::ErrorMessage errmsg(callstack, tokenizer?&tokenizer->list:0, severity, id, msg, cwe, false);
if (errorLogger)
errorLogger->reportErr(errmsg);
else
Check::reportError(errmsg);
}
void CheckMemoryLeak::memleakError(const Token *tok, const std::string &varname) const
{
reportErr(tok, Severity::error, "memleak", "Memory leak: " + varname, CWE(401U));
}
void CheckMemoryLeak::memleakUponReallocFailureError(const Token *tok, const std::string &varname) const
{
reportErr(tok, Severity::error, "memleakOnRealloc", "Common realloc mistake: \'" + varname + "\' nulled but not freed upon failure", CWE(401U));
}
void CheckMemoryLeak::resourceLeakError(const Token *tok, const std::string &varname) const
{
std::string errmsg("Resource leak");
if (!varname.empty())
errmsg += ": " + varname;
reportErr(tok, Severity::error, "resourceLeak", errmsg, CWE(775U));
}
void CheckMemoryLeak::deallocDeallocError(const Token *tok, const std::string &varname) const
{
reportErr(tok, Severity::error, "deallocDealloc", "Deallocating a deallocated pointer: " + varname, CWE(415U));
}
void CheckMemoryLeak::deallocuseError(const Token *tok, const std::string &varname) const
{
reportErr(tok, Severity::error, "deallocuse", "Dereferencing '" + varname + "' after it is deallocated / released", CWE(416U));
}
void CheckMemoryLeak::mismatchSizeError(const Token *tok, const std::string &sz) const
{
reportErr(tok, Severity::error, "mismatchSize", "The allocated size " + sz + " is not a multiple of the underlying type's size.", CWE(131U));
}
void CheckMemoryLeak::mismatchAllocDealloc(const std::list<const Token *> &callstack, const std::string &varname) const
{
reportErr(callstack, Severity::error, "mismatchAllocDealloc", "Mismatching allocation and deallocation: " + varname, CWE(762U));
}
CheckMemoryLeak::AllocType CheckMemoryLeak::functionReturnType(const Function* func, std::list<const Function*> *callstack) const
{
if (!func || !func->hasBody())
return No;
// Get return pointer..
unsigned int varid = 0;
for (const Token *tok2 = func->functionScope->classStart; tok2 != func->functionScope->classEnd; tok2 = tok2->next()) {
if (tok2->str() == "return") {
AllocType allocType = getAllocationType(tok2->next(), 0, callstack);
if (allocType != No)
return allocType;
if (tok2->scope() != func->functionScope || !tok2->astOperand1())
return No;
const Token* tok = tok2->astOperand1();
if (Token::Match(tok, ".|::"))
tok = tok->astOperand2() ? tok->astOperand2() : tok->astOperand1();
if (tok)
varid = tok->varId();
break;
}
}
// Not returning pointer value..
if (varid == 0)
return No;
// If variable is not local then alloctype shall be "No"
// Todo: there can be false negatives about mismatching allocation/deallocation.
// => Generate "alloc ; use ;" if variable is not local?
const Variable *var = tokenizer->getSymbolDatabase()->getVariableFromVarId(varid);
if (!var || !var->isLocal() || var->isStatic())
return No;
// Check if return pointer is allocated..
AllocType allocType = No;
for (const Token* tok = func->functionScope->classStart; tok != func->functionScope->classEnd; tok = tok->next()) {
if (Token::Match(tok, "%varid% =", varid)) {
allocType = getAllocationType(tok->tokAt(2), varid, callstack);
}
if (Token::Match(tok, "= %varid% ;", varid)) {
return No;
}
if (!tokenizer->isC() && Token::Match(tok, "[(,] %varid% [,)]", varid)) {
return No;
}
if (Token::Match(tok, "[(,] & %varid% [.,)]", varid)) {
return No;
}
if (allocType == No && tok->str() == "return")
return No;
}
return allocType;
}
const char *CheckMemoryLeak::functionArgAlloc(const Function *func, unsigned int targetpar, AllocType &allocType) const
{
allocType = No;
if (!func || !func->functionScope)
return "";
if (!Token::simpleMatch(func->retDef, "void"))
return "";
std::list<Variable>::const_iterator arg = func->argumentList.begin();
for (; arg != func->argumentList.end(); ++arg) {
if (arg->index() == targetpar-1)
break;
}
if (arg == func->argumentList.end())
return "";
// Is **
if (!arg->isPointer())
return "";
const Token* tok = arg->typeEndToken();
tok = tok->previous();
if (tok->str() != "*")
return "";
// Check if pointer is allocated.
int realloc = 0;
for (tok = func->functionScope->classStart; tok && tok != func->functionScope->classEnd; tok = tok->next()) {
if (tok->varId() == arg->declarationId()) {
if (Token::Match(tok->tokAt(-3), "free ( * %name% )")) {
realloc = 1;
allocType = No;
} else if (Token::Match(tok->previous(), "* %name% =")) {
allocType = getAllocationType(tok->tokAt(2), arg->declarationId());
if (allocType == No) {
allocType = getReallocationType(tok->tokAt(2), arg->declarationId());
}
if (allocType != No) {
if (realloc)
return "realloc";
return "alloc";
}
} else {
// unhandled variable usage: bailout
return "";
}
}
}
return "";
}
static bool notvar(const Token *tok, unsigned int varid)
{
if (!tok)
return false;
if (Token::Match(tok, "&&|;"))
return notvar(tok->astOperand1(),varid) || notvar(tok->astOperand2(),varid);
if (tok->str() == "(" && Token::Match(tok->astOperand1(), "UNLIKELY|LIKELY"))
return notvar(tok->astOperand2(), varid);
const Token *vartok = astIsVariableComparison(tok, "==", "0");
return vartok && (vartok->varId() == varid);
}
static bool ifvar(const Token *tok, unsigned int varid, const std::string &comp, const std::string &rhs)
{
if (!Token::simpleMatch(tok, "if ("))
return false;
const Token *condition = tok->next()->astOperand2();
if (condition && condition->str() == "(" && Token::Match(condition->astOperand1(), "UNLIKELY|LIKELY"))
condition = condition->astOperand2();
if (!condition || condition->str() == "&&")
return false;
const Token *vartok = astIsVariableComparison(condition, comp, rhs);
return (vartok && vartok->varId() == varid);
}
static bool alwaysTrue(const Token *tok)
{
if (!tok)
return false;
if (tok->values.size() == 1U &&
tok->values.front().intvalue != 0 &&
tok->values.front().isKnown())
return true;
if (tok->str() == "||")
return alwaysTrue(tok->astOperand1()) || alwaysTrue(tok->astOperand2());
if (tok->str() == "true")
return true;
return (tok->isComparisonOp() &&
tok->values.size() == 1U &&
tok->values.front().isKnown() &&
tok->values.front().intvalue != 0);
}
bool CheckMemoryLeakInFunction::test_white_list(const std::string &funcname, const Settings *settings, bool cpp)
{
return ((call_func_white_list.find(funcname)!=call_func_white_list.end()) || (settings->library.leakignore.find(funcname) != settings->library.leakignore.end()) || (cpp && funcname == "delete"));
}
namespace {
const std::set<std::string> call_func_keywords = make_container < std::set<std::string> > ()
<< "asprintf"
<< "delete"
<< "fclose"
<< "for"
<< "free"
<< "if"
<< "realloc"
<< "return"
<< "switch"
<< "while"
<< "sizeof";
}
const char * CheckMemoryLeakInFunction::call_func(const Token *tok, std::list<const Token *> callstack, const unsigned int varid, AllocType &alloctype, AllocType &dealloctype, bool &allocpar, unsigned int sz)
{
if (test_white_list(tok->str(), _settings, tokenizer->isCPP())) {
if (call_func_keywords.find(tok->str())!=call_func_keywords.end())
return 0;
// is the varid a parameter?
for (const Token *tok2 = tok->tokAt(2); tok2 && tok2 != tok->linkAt(1); tok2 = tok2->next()) {
if (tok2->str() == "(") {
tok2 = tok2->nextArgument();
if (!tok2)
break;
}
if (tok2->varId() == varid) {
if (tok->strAt(-1) == ".")
return "use";
else if (tok2->strAt(1) == "=")
return "assign";
else if (tok->str()=="printf")
return "use"; // <- it is not certain printf dereference the pointer TODO: check the format string
else
return "use_";
}
}
return 0;
}
if (_settings->library.isnoreturn(tok) && tok->strAt(-1) != "=")
return "exit";
if (varid > 0 && (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) && (*it)->str() == funcname)
return "recursive";
}
callstack.push_back(tok);
// lock/unlock..
if (varid == 0) {
const Function* func = tok->function();
if (!func || !func->hasBody())
return 0;
Token *ftok = getcode(func->functionScope->classStart->next(), callstack, 0, alloctype, dealloctype, false, 1);
simplifycode(ftok);
const char *ret = nullptr;
if (Token::simpleMatch(ftok, "; alloc ; }"))
ret = "alloc";
else if (Token::simpleMatch(ftok, "; dealloc ; }"))
ret = "dealloc";
TokenList::deleteTokens(ftok);
return ret;
}
// how many parameters is there in the function call?
const unsigned int numpar = countParameters(tok);
if (numpar == 0) {
// Taking return value => it is not a noreturn function
if (tok->strAt(-1) == "=")
return nullptr;
// Function is not noreturn
if (tok->function() && tok->function()->functionScope) {
std::string temp;
if (!_settings->library.isScopeNoReturn(tok->function()->functionScope->classEnd, &temp) && temp.empty())
return nullptr;
} else if (_settings->library.isnotnoreturn(tok))
return nullptr;
return "callfunc";
}
unsigned int par = 0;
const bool dot(tok->previous()->str() == ".");
const bool eq(tok->previous()->str() == "=");
const Token *functok = tok;
tok = Token::findsimplematch(tok, "(");
if (tok)
tok = tok->next();
for (; tok; tok = tok->nextArgument()) {
++par;
if (Token::Match(tok, "%varid% [,()]", varid)) {
if (dot)
return "use";
const Function* function = functok->function();
if (!function)
return "use";
// how many parameters does the function want?
if (numpar != function->argCount()) // TODO: Handle default parameters
return "recursive";
if (!function->functionScope)
return "use";
const Variable* param = function->getArgumentVar(par-1);
if (!param || !param->nameToken())
return "use";
Token *func = getcode(function->functionScope->classStart->next(), callstack, param->declarationId(), alloctype, dealloctype, false, sz);
//simplifycode(func);
const Token *func_ = func;
while (func_ && func_->str() == ";")
func_ = func_->next();
const char *ret = nullptr;
/** @todo handle "goto" */
if (Token::findsimplematch(func_, "dealloc"))
ret = "dealloc";
else if (Token::findsimplematch(func_, "use"))
ret = "use";
else if (Token::findsimplematch(func_, "&use"))
ret = "&use";
TokenList::deleteTokens(func);
return ret;
}
if (Token::Match(tok, "& %varid% [,()]", varid)) {
const Function *func = functok->function();
if (func == nullptr)
continue;
AllocType a;
const char *ret = functionArgAlloc(func, par, a);
if (a != No) {
if (alloctype == No)
alloctype = a;
else if (alloctype != a)
alloctype = Many;
allocpar = true;
return ret;
}
}
if (Token::Match(tok, "%varid% . %name% [,)]", varid))
return "use";
}
return (eq || _settings->experimental) ? 0 : "callfunc";
}
static void addtoken(Token **rettail, const Token *tok, const std::string &str)
{
(*rettail)->insertToken(str);
(*rettail) = (*rettail)->next();
(*rettail)->linenr(tok->linenr());
(*rettail)->fileIndex(tok->fileIndex());
}
Token *CheckMemoryLeakInFunction::getcode(const Token *tok, std::list<const Token *> callstack, const unsigned int varid, CheckMemoryLeak::AllocType &alloctype, CheckMemoryLeak::AllocType &dealloctype, bool classmember, unsigned int sz)
{
// variables whose value depends on if(!var). If one of these variables
// is used in a if-condition then generate "ifv" instead of "if".
std::set<unsigned int> extravar;
// The first token should be ";"
Token* rethead = new Token(0);
rethead->str(";");
rethead->linenr(tok->linenr());
rethead->fileIndex(tok->fileIndex());
Token* rettail = rethead;
int indentlevel = 0;
int parlevel = 0;
for (; tok; tok = tok->next()) {
if (tok->str() == "{") {
addtoken(&rettail, tok, "{");
++indentlevel;
} else if (tok->str() == "}") {
addtoken(&rettail, tok, "}");
if (indentlevel <= 0)
break;
--indentlevel;
}
else if (tok->str() == "(")
++parlevel;
else if (tok->str() == ")")
--parlevel;
if (parlevel == 0 && tok->str() == ";")
addtoken(&rettail, tok, ";");
// Start of new statement.. check if the statement has anything interesting
if (varid > 0 && parlevel == 0 && Token::Match(tok, "[;{}]")) {
if (Token::Match(tok->next(), "[{};]"))
continue;
// function calls are interesting..
const Token *tok2 = tok;
while (Token::Match(tok2->next(), "%name% ."))
tok2 = tok2->tokAt(2);
if (Token::Match(tok2->next(), "%name% ("))
;
else if (Token::Match(tok->next(), "continue|break|return|throw|goto|do|else"))
;
else {
const Token *skipToToken = nullptr;
// scan statement for interesting keywords / varid
for (tok2 = tok->next(); tok2; tok2 = tok2->next()) {
if (tok2->str() == ";") {
// nothing interesting found => skip this statement
skipToToken = tok2->previous();
break;
}
if (tok2->varId() == varid ||
tok2->str() == ":" || tok2->str() == "{" || tok2->str() == "}") {
break;
}
}
if (skipToToken) {
tok = skipToToken;
continue;
}
}
}
if (varid == 0) {
if (!callstack.empty() && Token::Match(tok, "[;{}] __cppcheck_lock|__cppcheck_unlock ( ) ;")) {
// Type of leak = Resource leak
alloctype = dealloctype = CheckMemoryLeak::File;
if (tok->next()->str() == "__cppcheck_lock") {
addtoken(&rettail, tok, "alloc");
} else {
addtoken(&rettail, tok, "dealloc");
}
tok = tok->tokAt(3);
continue;
}
if (Token::simpleMatch(tok, "if (")) {
addtoken(&rettail, tok, "if");
tok = tok->next()->link();
continue;
}
} else {
if (Token::Match(tok, "%varid% = close ( %varid% )", varid)) {
addtoken(&rettail, tok, "dealloc");
addtoken(&rettail, tok, ";");
addtoken(&rettail, tok, "assign");
addtoken(&rettail, tok, ";");
tok = tok->tokAt(5);
continue;
}
// var = strcpy|.. ( var ,
if (Token::Match(tok, "[;{}] %varid% = memcpy|memmove|memset|strcpy|strncpy|strcat|strncat ( %varid% ,", varid)) {
tok = tok->linkAt(4);
continue;
}
if (Token::Match(tok->previous(), "[(;{}] %varid% =", varid) ||
Token::Match(tok, "asprintf|vasprintf ( & %varid% ,", varid)) {
CheckMemoryLeak::AllocType alloc;
if (Token::Match(tok, "asprintf|vasprintf (")) {
// todo: check how the return value is used.
if (!Token::Match(tok->previous(), "[;{}]")) {
TokenList::deleteTokens(rethead);
return 0;
}
alloc = Malloc;
tok = tok->next()->link();
} else {
alloc = getAllocationType(tok->tokAt(2), varid);
}
if (sz > 1 &&
Token::Match(tok->tokAt(2), "malloc ( %num% )") &&
(MathLib::toLongNumber(tok->strAt(4)) % long(sz)) != 0) {
mismatchSizeError(tok->tokAt(4), tok->strAt(4));
}
if (alloc == CheckMemoryLeak::No) {
alloc = getReallocationType(tok->tokAt(2), varid);
if (alloc != CheckMemoryLeak::No) {
addtoken(&rettail, tok, "realloc");
addtoken(&rettail, tok, ";");
tok = tok->tokAt(2);
if (Token::Match(tok, "%name% ("))
tok = tok->next()->link();
continue;
}
}
// don't check classes..
if (alloc == CheckMemoryLeak::New) {
if (Token::Match(tok->tokAt(2), "new struct| %type% [(;]")) {
const int offset = tok->strAt(3) == "struct" ? 1 : 0;
if (isclass(tok->tokAt(3 + offset), varid)) {
alloc = No;
}
} else if (Token::Match(tok->tokAt(2), "new ( nothrow ) struct| %type%")) {
const int offset = tok->strAt(6) == "struct" ? 1 : 0;
if (isclass(tok->tokAt(6 + offset), varid)) {
alloc = No;
}
} else if (Token::Match(tok->tokAt(2), "new ( std :: nothrow ) struct| %type%")) {
const int offset = tok->strAt(8) == "struct" ? 1 : 0;
if (isclass(tok->tokAt(8 + offset), varid)) {
alloc = No;
}
}
if (Token::simpleMatch(tok->next(), "= new")) {
tok = tok->tokAt(2);
while (Token::Match(tok->next(), "%name%|::|(|[")) {
if (Token::Match(tok->next(), "(|["))
tok = tok->linkAt(1);
else
tok = tok->next();
}
}
if (alloc == No && alloctype == No)
alloctype = CheckMemoryLeak::New;
}
if (alloc != No) {
addtoken(&rettail, tok, "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;
if (Token::Match(tok, "%name% = %type% (")) {
tok = tok->linkAt(3);
continue;
}
}
// assignment..
else {
// is the pointer in rhs?
bool rhs = false;
bool trailingSemicolon = false;
bool used = false;
for (const Token *tok2 = tok->next(); tok2; tok2 = tok2->next()) {
if (tok2->str() == ";") {
trailingSemicolon = true;
if (rhs)
tok = tok2;
break;
}
if (!used && !rhs) {
if (Token::Match(tok2, "[=+(,] %varid%", varid)) {
if (Token::Match(tok2, "[(,]")) {
used = true;
addtoken(&rettail, tok, "use");
addtoken(&rettail, tok, ";");
}
rhs = true;
}
}
}
if (!used) {
if (!rhs)
addtoken(&rettail, tok, "assign");
else {
addtoken(&rettail, tok, "use_");
if (trailingSemicolon)
addtoken(&rettail, tok, ";");
}
}
continue;
}
}
if (Token::Match(tok->previous(), "%op%|;|{|}|) ::| %name%") || (Token::Match(tok->previous(), "( ::| %name%") && (!rettail || rettail->str() != "loop"))) {
if (tok->str() == "::")
tok = tok->next();
if (Token::Match(tok, "%varid% ?", varid))
tok = tok->tokAt(2);
AllocType dealloc = getDeallocationType(tok, varid);
if (dealloc != No && tok->str() == "fcloseall" && alloctype != dealloc)
;
else if (dealloc != No) {
addtoken(&rettail, tok, "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;
if (tok->strAt(2) == "(")
tok = tok->linkAt(2);
continue;
}
}
// if else switch
if (Token::simpleMatch(tok, "if (")) {
if (alloctype == Fd) {
if (ifvar(tok, varid, ">", "-1") ||
ifvar(tok, varid, ">=", "0") ||
ifvar(tok, varid, ">", "0") ||
ifvar(tok, varid, "!=", "-1")) {
addtoken(&rettail, tok, "if(var)");
tok = tok->next()->link();
continue;
} else if (ifvar(tok, varid, "==", "-1") ||
ifvar(tok, varid, "<", "0")) {
addtoken(&rettail, tok, "if(!var)");
tok = tok->next()->link();
continue;
}
}
if (ifvar(tok, varid, "!=", "0")) {
addtoken(&rettail, tok, "if(var)");
// Make sure the "use" will not be added
tok = tok->next()->link();
continue;
} else if (ifvar(tok, varid, "==", "0")) {
addtoken(&rettail, tok, "if(!var)");
// parse the if-body.
// if a variable is assigned then add variable to "extravar".
for (const Token *tok2 = tok->next()->link()->tokAt(2); tok2; tok2 = tok2->next()) {
if (tok2->str() == "{")
tok2 = tok2->link();
else if (tok2->str() == "}")
break;
else if (Token::Match(tok2, "%var% ="))
extravar.insert(tok2->varId());
}
tok = tok->next()->link();
continue;
} else {
// Check if the condition depends on var or extravar somehow..
bool dep = false;
const Token* const end = tok->linkAt(1);
for (const Token *tok2 = tok->next(); tok2 != end; tok2 = tok2->next()) {
if (Token::Match(tok2, "close|pclose|fclose|closedir ( %varid% )", varid)) {
addtoken(&rettail, tok, "dealloc");
addtoken(&rettail, tok, ";");
dep = true;
break;
} else if (alloctype == Fd && Token::Match(tok2, "%varid% !=|>=", varid)) {
dep = true;
} else if (Token::Match(tok2, "! %varid%", varid)) {
dep = true;
} else if (Token::Match(tok2, "%name% (") && !test_white_list(tok2->str(), _settings, tokenizer->isCPP())) {
bool use = false;
for (const Token *tok3 = tok2->tokAt(2); tok3; tok3 = tok3->nextArgument()) {
if (Token::Match(tok3->previous(), "(|, &| %varid% ,|)", varid)) {
use = true;
break;