walkero
/
cppcheck
1
0
Fork 0
Code Issues Pull Requests Projects Releases 1 Wiki Activity

Improved STL checks: 

- Added performance checking for .c_str() for return values and function parameters (#1079)
- Added more containers (basic_string, C++11 containers) and more functions to checking (.at, .resize, .reserve, ...)
- Make use of symboldatabase in missingComparision check
This commit is contained in:
PKEuS 2012-02-25 12:43:27 +01:00
parent 9a5f66030c
commit 9431fb1b7e
5 changed files with 269 additions and 109 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

274
lib/checkstl.cpp
View File

@ -278,7 +278,9 @@ void CheckStl::stlOutOfBounds()
if (Token::simpleMatch(tok3->next(), ". size ( )"))
break;
else if (Token::Match(tok3->next(), "[ %varid% ]", numId))
stlOutOfBoundsError(tok3, tok3->strAt(2), tok3->str());
stlOutOfBoundsError(tok3, tok3->strAt(2), tok3->str(), false);
else if (Token::Match(tok3->next(), ". at ( %varid% )", numId))
stlOutOfBoundsError(tok3, tok3->strAt(4), tok3->str(), true);
}
}
break;
@ -288,9 +290,12 @@ void CheckStl::stlOutOfBounds()
}
// Error message for bad iterator usage..
void CheckStl::stlOutOfBoundsError(const Token *tok, const std::string &num, const std::string &var)
void CheckStl::stlOutOfBoundsError(const Token *tok, const std::string &num, const std::string &var, bool at)
{
reportError(tok, Severity::error, "stlOutOfBounds", "When " + num + "==" + var + ".size(), " + var + "[" + num + "] is out of bounds");
if (at)
reportError(tok, Severity::error, "stlOutOfBounds", "When " + num + "==" + var + ".size(), " + var + ".at(" + num + ") is out of bounds");
else
reportError(tok, Severity::error, "stlOutOfBounds", "When " + num + "==" + var + ".size(), " + var + "[" + num + "] is out of bounds");
}
@ -486,7 +491,7 @@ void CheckStl::eraseError(const Token *tok)
void CheckStl::pushback()
{
// Pointer can become invalid after push_back or push_front..
// Pointer can become invalid after push_back, push_front, reserve or resize..
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
if (Token::Match(tok, "%var% = & %var% [")) {
// Variable id for pointer
@ -512,7 +517,7 @@ void CheckStl::pushback()
}
// push_back on vector..
if (Token::Match(tok2, "%varid% . push_front|push_back", containerId))
if (Token::Match(tok2, "%varid% . push_front|push_back|resize|reserve", containerId))
invalidPointer = true;
// Using invalid pointer..
@ -527,7 +532,7 @@ void CheckStl::pushback()
}
}
// Iterator becomes invalid after reserve, push_back or push_front..
// Iterator becomes invalid after reserve, resize, insert, push_back or push_front..
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
if (!Token::simpleMatch(tok, "vector <"))
continue;
@ -597,7 +602,7 @@ void CheckStl::pushback()
} else if (tok3->str() == "break" || tok3->str() == "return") {
pushbackTok = 0;
break;
} else if (Token::Match(tok3, "%varid% . push_front|push_back|insert|reserve (", varId)) {
} else if (Token::Match(tok3, "%varid% . push_front|push_back|insert|reserve|resize (", varId)) {
pushbackTok = tok3->tokAt(2);
}
}
@ -618,7 +623,7 @@ void CheckStl::pushback()
}
// push_back on vector..
if (vectorid > 0 && Token::Match(tok2, "%varid% . push_front|push_back|insert|reserve (", vectorid)) {
if (vectorid > 0 && Token::Match(tok2, "%varid% . push_front|push_back|insert|reserve|resize (", vectorid)) {
if (!invalidIterator.empty() && Token::Match(tok2->tokAt(2), "insert ( %varid% ,", iteratorid)) {
invalidIteratorError(tok2, invalidIterator, tok2->strAt(4));
break;
@ -664,7 +669,7 @@ void CheckStl::invalidPointerError(const Token *tok, const std::string &pointer_
void CheckStl::stlBoundries()
{
// containers (not the vector)..
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|hash_map|hash_multimap|hash_set";
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|hash_map|hash_multimap|hash_set|unordered_map|unordered_multimap|unordered_set|unordered_multiset";
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
// Declaring iterator..
@ -717,14 +722,16 @@ void CheckStl::if_find()
const SymbolDatabase *symbolDatabase = _tokenizer->getSymbolDatabase();
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
if (i->type != Scope::eIf && i->type != Scope::eElseIf)
if ((i->type != Scope::eIf && i->type != Scope::eElseIf) || !i->classDef)
continue;
const Token* tok = i->classDef;
const Token* tok = i->classDef->next();
if (tok->str() == "if")
tok = tok->next();
if (Token::Match(tok, "if ( !| %var% . find (")) {
if (Token::Match(tok, "( !| %var% . find (")) {
// goto %var%
tok = tok->tokAt(2);
tok = tok->next();
if (tok->str() == "!")
tok = tok->next();
if (!Token::simpleMatch(tok->linkAt(3), ") )"))
@ -747,8 +754,8 @@ void CheckStl::if_find()
}
//check also for vector-like or pointer containers
else if (Token::Match(tok, "if ( !| * %var%") || Token::Match(tok, "if ( !| %var% [")) {
tok = tok->tokAt(2);
else if (Token::Match(tok, "( !| * %var%") || Token::Match(tok, "( !| %var% [")) {
tok = tok->next();
const Token *tok2 = tok;
if (tok2->str() == "!")
@ -811,9 +818,9 @@ void CheckStl::if_find()
}
}
else if (Token::Match(tok, "if ( !| std :: find|find_if (")) {
else if (Token::Match(tok, "( !| std :: find|find_if (")) {
// goto '(' for the find
tok = tok->tokAt(4);
tok = tok->tokAt(3);
if (tok->str() != "(")
tok = tok->next();
@ -863,7 +870,7 @@ bool CheckStl::isStlContainer(unsigned int varid)
type = type->tokAt(2);
// all possible stl containers as a token
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|hash_map|hash_multimap|hash_set|vector <";
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|vector|hash_map|hash_multimap|hash_set|unordered_map|unordered_multimap|unordered_set|unordered_multiset|basic_string";
// check if it's an stl template
if (Token::Match(type, STL_CONTAINER_LIST))
@ -943,9 +950,8 @@ void CheckStl::sizeError(const Token *tok)
void CheckStl::redundantCondition()
{
const char pattern[] = "if ( %var% . find ( %any% ) != %var% . end|rend ( ) ) "
"{|{|"
" %var% . remove ( %any% ) ; "
"}|}|";
"{"
" %var% . remove ( %any% ) ;";
const Token *tok = Token::findmatch(_tokenizer->tokens(), pattern);
while (tok) {
bool b(tok->strAt(15) == "{");
@ -978,64 +984,67 @@ void CheckStl::redundantIfRemoveError(const Token *tok)
void CheckStl::missingComparison()
{
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
if (Token::simpleMatch(tok, "for (")) {
for (const Token *tok2 = tok->tokAt(2); tok2; tok2 = tok2->next()) {
if (tok2->str() == ";")
break;
const SymbolDatabase* const symbolDatabase = _tokenizer->getSymbolDatabase();
if (!Token::Match(tok2, "%var% = %var% . begin|rbegin|cbegin|crbegin ( ) ; %var% != %var% . end|rend|cend|crend ( ) ; ++| %var% ++| ) {"))
continue;
for (std::list<Scope>::const_iterator i = symbolDatabase->scopeList.begin(); i != symbolDatabase->scopeList.end(); ++i) {
if (i->type != Scope::eFor || !i->classDef)
continue;
// same iterator name
if (tok2->str() != tok2->strAt(8))
continue;
for (const Token *tok2 = i->classDef->tokAt(2); tok2 != i->classStart; tok2 = tok2->next()) {
if (tok2->str() == ";")
break;
// same container
if (tok2->strAt(2) != tok2->strAt(10))
continue;
if (!Token::Match(tok2, "%var% = %var% . begin|rbegin|cbegin|crbegin ( ) ; %var% != %var% . end|rend|cend|crend ( ) ; ++| %var% ++| ) {"))
continue;
// increment iterator
if (!Token::simpleMatch(tok2->tokAt(16), ("++ " + tok2->str() + " )").c_str()) &&
!Token::simpleMatch(tok2->tokAt(16), (tok2->str() + " ++ )").c_str())) {
continue;
}
// same iterator name
if (tok2->str() != tok2->strAt(8))
continue;
const unsigned int &iteratorId(tok2->varId());
if (iteratorId == 0)
continue;
// same container
if (tok2->strAt(2) != tok2->strAt(10))
continue;
const Token *incrementToken = 0;
// Count { and } for tok3
unsigned int indentlevel = 0;
// Parse loop..
for (const Token *tok3 = tok2->tokAt(20); tok3; tok3 = tok3->next()) {
if (tok3->str() == "{")
++indentlevel;
else if (tok3->str() == "}") {
if (indentlevel == 0)
break;
--indentlevel;
} else if (Token::Match(tok3, "%varid% ++", iteratorId))
incrementToken = tok3;
else if (Token::Match(tok3->previous(), "++ %varid% !!.", iteratorId))
incrementToken = tok3;
else if (Token::Match(tok3, "%varid% !=|==", iteratorId))
incrementToken = 0;
else if (tok3->str() == "break" || tok3->str() == "return")
incrementToken = 0;
else if (Token::Match(tok3, "%varid% = %var% . insert ( ++| %varid% ++| ,", iteratorId)) {
// skip insertion..
tok3 = tok3->linkAt(6);
if (!tok3)
break;
}
}
if (incrementToken)
missingComparisonError(incrementToken, tok2->tokAt(16));
// increment iterator
if (!Token::simpleMatch(tok2->tokAt(16), ("++ " + tok2->str() + " )").c_str()) &&
!Token::simpleMatch(tok2->tokAt(16), (tok2->str() + " ++ )").c_str())) {
continue;
}
const unsigned int &iteratorId(tok2->varId());
if (iteratorId == 0)
continue;
const Token *incrementToken = 0;
// Count { and } for tok3
unsigned int indentlevel = 0;
// Parse loop..
for (const Token *tok3 = tok2->tokAt(20); tok3; tok3 = tok3->next()) {
if (tok3->str() == "{")
++indentlevel;
else if (tok3->str() == "}") {
if (indentlevel == 0)
break;
--indentlevel;
} else if (Token::Match(tok3, "%varid% ++", iteratorId))
incrementToken = tok3;
else if (Token::Match(tok3->previous(), "++ %varid% !!.", iteratorId))
incrementToken = tok3;
else if (Token::Match(tok3, "%varid% !=|==", iteratorId))
incrementToken = 0;
else if (tok3->str() == "break" || tok3->str() == "return")
incrementToken = 0;
else if (Token::Match(tok3, "%varid% = %var% . insert ( ++| %varid% ++| ,", iteratorId)) {
// skip insertion..
tok3 = tok3->linkAt(6);
if (!tok3)
break;
}
}
if (incrementToken)
missingComparisonError(incrementToken, tok2->tokAt(16));
}
}
}
@ -1066,30 +1075,80 @@ void CheckStl::string_c_str()
return;
const SymbolDatabase* symbolDatabase = _tokenizer->getSymbolDatabase();
// Try to detect common problems when using string::c_str()
for (std::list<Scope>::const_iterator scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
for (std::list<Function>::const_iterator func = scope->functionList.begin(); func != scope->functionList.end(); ++func) {
for (const Token *tok = func->start; tok && tok != func->start->link(); tok = tok->next()) {
// Invalid usage..
if (Token::Match(tok, "throw %var% . c_str ( ) ;") && isLocal(symbolDatabase, tok->next()->varId())) {
string_c_strThrowError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% . str ( ) . c_str ( ) ;")) {
const Variable* var = symbolDatabase->getVariableFromVarId(tok->next()->varId());
if (var && var->isPointer())
string_c_strError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% (") &&
Token::simpleMatch(tok->linkAt(4), ") . c_str ( ) ;") &&
Token::findmatch(_tokenizer->tokens(), ("std :: string " + tok->strAt(3) + " (").c_str())) {
const Variable* var = symbolDatabase->getVariableFromVarId(tok->next()->varId());
if (var && var->isPointer())
string_c_strError(tok);
// Find all functions that take std::string as argument
std::multimap<std::string, unsigned int> c_strFuncParam;
if (_settings->isEnabled("performance")) {
for (std::list<Scope>::const_iterator scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
if (scope->type == Scope::eFunction && scope->function) {
if (c_strFuncParam.erase(scope->className) != 0) { // Check if function with this name was already found
c_strFuncParam.insert(std::make_pair(scope->className, 0)); // Disable, because there are overloads. TODO: Handle overloads
continue;
}
// Using c_str() to get the return value is only dangerous if the function returns a char*
if (!Token::simpleMatch(func->tokenDef->tokAt(-2), "char *"))
continue;
unsigned int numpar = 0;
c_strFuncParam.insert(std::make_pair(scope->className, numpar)); // Insert function as dummy, to indicate that there is at least one function with that name
for (const Token* tok = scope->function->arg->next(); tok != 0; tok = tok->nextArgument()) {
numpar++;
if (Token::Match(tok, "std :: string !!&") || Token::simpleMatch(tok, "const std :: string"))
c_strFuncParam.insert(std::make_pair(scope->className, numpar));
}
}
}
}
// Try to detect common problems when using string::c_str()
for (std::list<Scope>::const_iterator scope = symbolDatabase->scopeList.begin(); scope != symbolDatabase->scopeList.end(); ++scope) {
if (scope->type != Scope::eFunction || !scope->function)
continue;
enum {charPtr, stdString, stdStringConstRef, Other} returnType = Other;
if (Token::simpleMatch(scope->function->tokenDef->tokAt(-2), "char *"))
returnType = charPtr;
else if (Token::simpleMatch(scope->function->tokenDef->tokAt(-5), "const std :: string &"))
returnType = stdStringConstRef;
else if (Token::Match(scope->function->tokenDef->tokAt(-3), "std :: string !!&"))
returnType = stdString;
for (const Token *tok = scope->function->start; tok && tok != scope->function->start->link(); tok = tok->next()) {
// Invalid usage..
if (Token::Match(tok, "throw %var% . c_str ( ) ;") && isLocal(symbolDatabase, tok->next()->varId())) {
string_c_strThrowError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% . str ( ) . c_str ( ) ;")) {
const Variable* var = symbolDatabase->getVariableFromVarId(tok->next()->varId());
if (var && var->isPointer())
string_c_strError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% (") &&
Token::simpleMatch(tok->linkAt(4), ") . c_str ( ) ;") &&
Token::findmatch(_tokenizer->tokens(), ("std :: string " + tok->strAt(3) + " (").c_str())) {
const Variable* var = symbolDatabase->getVariableFromVarId(tok->next()->varId());
if (var && var->isPointer())
string_c_strError(tok);
} else if (Token::Match(tok, "%var% ( !!)") && c_strFuncParam.find(tok->str()) != c_strFuncParam.end() && _settings->isEnabled("performance") && !Token::Match(tok->previous(), "::|.")) { // calling function. TODO: Add support for member functions
std::pair<std::multimap<std::string, unsigned int>::const_iterator, std::multimap<std::string, unsigned int>::const_iterator> range = c_strFuncParam.equal_range(tok->str());
for (std::multimap<std::string, unsigned int>::const_iterator i = range.first; i != range.second; ++i) {
if (i->second == 0)
continue;
const Token* tok2 = tok->tokAt(2);
unsigned int j;
for (j = 0; tok2 && j < i->second-1; j++)
tok2 = tok2->nextArgument();
if (tok2)
tok2 = tok2->nextArgument();
else
break;
if (!tok2 && j == i->second-1)
tok2 = tok->next()->link();
else
tok2 = tok2->previous();
if (tok2 && Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )"))
string_c_strParam(tok, i->second);
}
}
// Using c_str() to get the return value is only dangerous if the function returns a char*
if (returnType == charPtr) {
if (Token::Match(tok, "return %var% . c_str ( ) ;") && isLocal(symbolDatabase, tok->next()->varId())) {
string_c_strError(tok);
} else if (Token::Match(tok, "return %var% . str ( ) . c_str ( ) ;") && isLocal(symbolDatabase, tok->next()->varId())) {
@ -1100,7 +1159,7 @@ void CheckStl::string_c_str()
} else if (Token::simpleMatch(tok, "return (") &&
Token::simpleMatch(tok->next()->link(), ") . c_str ( ) ;")) {
// Check for "+ localvar" or "+ std::string(" inside the bracket
bool is_implicit_std_string = false;
bool is_implicit_std_string = _settings->inconclusive;
const Token *search_end = tok->next()->link();
for (const Token *search_tok = tok->tokAt(2); search_tok != search_end; search_tok = search_tok->next()) {
if (Token::Match(search_tok, "+ %var%") && isLocal(symbolDatabase, search_tok->next()->varId())) {
@ -1116,6 +1175,14 @@ void CheckStl::string_c_str()
string_c_strError(tok);
}
}
// Using c_str() to get the return value is redundant if the function returns std::string or const std::string&.
else if ((returnType == stdString || returnType == stdStringConstRef) && _settings->isEnabled("performance")) {
if (tok->str() == "return") {
const Token* tok2 = Token::findsimplematch(tok->next(), ";");
if (Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )"))
string_c_strReturn(tok);
}
}
}
}
}
@ -1132,6 +1199,20 @@ void CheckStl::string_c_strError(const Token* tok)
"Dangerous usage of c_str(). The c_str() return value is only valid until its string is deleted.");
}
void CheckStl::string_c_strReturn(const Token* tok)
{
reportError(tok, Severity::performance, "stlcstrReturn", "Returning the result of c_str() in a function that returns std::string is slow and redundant.\n"
"The conversion from const char* as returned by c_str to std::string creates an unecessary string copy. Solve that by directly returning the string.");
}
void CheckStl::string_c_strParam(const Token* tok, unsigned int number)
{
std::ostringstream oss;
oss << "Passing the result of c_str() to a function that takes std::string as argument " << number << " is slow and redundant.\n"
"The conversion from const char* as returned by c_str to std::string creates an unecessary string copy. Solve that by directly passing the string.";
reportError(tok, Severity::performance, "stlcstrParam", oss.str());
}
static bool hasArrayEnd(const Token *tok1)
{
const Token *end = Token::findsimplematch(tok1, ";");
@ -1154,8 +1235,7 @@ void CheckStl::checkAutoPointer()
return;
std::set<unsigned int> autoPtrVarId;
std::set<unsigned int>::const_iterator iter;
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|hash_map|hash_multimap|hash_set|vector";
static const char STL_CONTAINER_LIST[] = "bitset|deque|list|map|multimap|multiset|priority_queue|queue|set|stack|vector|hash_map|hash_multimap|hash_set|unordered_map|unordered_multimap|unordered_set|unordered_multiset|basic_string";
for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next()) {
if (Token::simpleMatch(tok, "auto_ptr <")) {
@ -1196,14 +1276,14 @@ void CheckStl::checkAutoPointer()
} else {
if (Token::Match(tok, "%var% = %var% ;")) {
if (_settings->isEnabled("style")) {
iter = autoPtrVarId.find(tok->tokAt(2)->varId());
std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->tokAt(2)->varId());
if (iter != autoPtrVarId.end()) {
autoPointerError(tok->tokAt(2));
}
}
} else if ((Token::Match(tok, "%var% = new %type% ") && hasArrayEnd(tok)) ||
(Token::Match(tok, "%var% . reset ( new %type% ") && hasArrayEndParen(tok))) {
iter = autoPtrVarId.find(tok->varId());
std::set<unsigned int>::const_iterator iter = autoPtrVarId.find(tok->varId());
if (iter != autoPtrVarId.end()) {
autoPointerArrayError(tok);
}

8
lib/checkstl.h
View File

@ -135,6 +135,8 @@ public:
void string_c_str();
void string_c_strThrowError(const Token *tok);
void string_c_strError(const Token *tok);
void string_c_strReturn(const Token *tok);
void string_c_strParam(const Token *tok, unsigned int number);
/** @brief %Check for use and copy auto pointer */
void checkAutoPointer();
@ -153,7 +155,7 @@ private:
*/
void eraseCheckLoop(const Token *it);
void stlOutOfBoundsError(const Token *tok, const std::string &num, const std::string &var);
void stlOutOfBoundsError(const Token *tok, const std::string &num, const std::string &var, bool at);
void invalidIteratorError(const Token *tok, const std::string &iteratorName);
void iteratorsError(const Token *tok, const std::string &container1, const std::string &container2);
void mismatchingContainersError(const Token *tok);
@ -178,7 +180,7 @@ private:
c.iteratorsError(0, "container1", "container2");
c.mismatchingContainersError(0);
c.dereferenceErasedError(0, "iter");
c.stlOutOfBoundsError(0, "i", "foo");
c.stlOutOfBoundsError(0, "i", "foo", false);
c.eraseError(0);
c.invalidIteratorError(0, "push_back|push_front|insert", "iterator");
c.invalidPointerError(0, "pointer");
@ -186,6 +188,8 @@ private:
c.if_findError(0, false);
c.if_findError(0, true);
c.string_c_strError(0);
c.string_c_strReturn(0);
c.string_c_strParam(0, 0);
c.sizeError(0);
c.redundantIfRemoveError(0);
c.autoPointerError(0);

2
lib/tokenize.cpp
View File

@ -7787,7 +7787,7 @@ std::string Tokenizer::fileLine(const Token *tok) const
return ostr.str();
}
std::string Tokenizer::file(const Token *tok) const
const std::string& Tokenizer::file(const Token *tok) const
{
return _files.at(tok->fileIndex());
}

2
lib/tokenize.h
View File

@ -199,7 +199,7 @@ public:
* @param tok The given token
* @return filename for the given token
*/
std::string file(const Token *tok) const;
const std::string& file(const Token *tok) const;
/**
* get error messages that the tokenizer generate

92
test/teststl.cpp
View File

@ -418,6 +418,13 @@ private:
"}\n");
ASSERT_EQUALS("[test.cpp:6]: (error) When ii==foo.size(), foo[ii] is out of bounds\n", errout.str());
check("void foo(std::vector<int> foo) {\n"
" for (unsigned int ii = 0; ii <= foo.size(); ++ii) {\n"
" foo.at(ii) = 0;\n"
" }\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) When ii==foo.size(), foo.at(ii) is out of bounds\n", errout.str());
check("void foo()\n"
"{\n"
" std::vector<int> foo;\n"
@ -1478,13 +1485,6 @@ private:
"}");
ASSERT_EQUALS("[test.cpp:3]: (error) Dangerous usage of c_str(). The returned value by c_str() is invalid after this call.\n", errout.str());
// Implicit conversion back to std::string
check("std::string get_msg() {\n"
" std::string errmsg;\n"
" return errmsg.c_str();\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" std::ostringstream errmsg;\n"
" const char *c = errmsg.str().c_str();\n"
@ -1498,13 +1498,89 @@ private:
"}");
ASSERT_EQUALS("[test.cpp:4]: (error) Dangerous usage of c_str(). The returned value by c_str() is invalid after this call.\n", errout.str());
check("const char* foo() {\n"
" static std::string text;\n"
" text = \"hello world\n\";\n"
" return text.c_str();\n"
"}");
ASSERT_EQUALS("", errout.str()); // #3427
// Implicit conversion back to std::string
check("std::string get_msg() {\n"
" std::string errmsg;\n"
" return errmsg.c_str();\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (performance) Returning the result of c_str() in a function that returns std::string is slow and redundant.\n", errout.str());
check("const std::string& get_msg() {\n"
" std::string errmsg;\n"
" return errmsg.c_str();\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (performance) Returning the result of c_str() in a function that returns std::string is slow and redundant.\n", errout.str());
check("std::string get_msg() {\n"
" std::string errmsg;\n"
" return errmsg;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void Foo1(const std::string& str) {}\n"
"void Foo2(char* c, const std::string str) {}\n"
"void Foo3(std::string& rstr) {}\n"
"void Foo4(std::string str, const std::string& str) {}\n"
"void Bar() {\n"
" std::string str = \"bar\";\n"
" Foo1(str);\n"
" Foo1(str.c_str());\n"
" Foo2(str.c_str(), str);\n"
" Foo2(str.c_str(), str.c_str());\n"
" Foo3(str.c_str());\n"
" Foo4(str, str);\n"
" Foo4(str.c_str(), str);\n"
" Foo4(str, str.c_str());\n"
" Foo4(str.c_str(), str.c_str());\n"
"}");
ASSERT_EQUALS("[test.cpp:8]: (performance) Passing the result of c_str() to a function that takes std::string as argument 1 is slow and redundant.\n"
"[test.cpp:10]: (performance) Passing the result of c_str() to a function that takes std::string as argument 2 is slow and redundant.\n"
"[test.cpp:13]: (performance) Passing the result of c_str() to a function that takes std::string as argument 1 is slow and redundant.\n"
"[test.cpp:14]: (performance) Passing the result of c_str() to a function that takes std::string as argument 2 is slow and redundant.\n"
"[test.cpp:15]: (performance) Passing the result of c_str() to a function that takes std::string as argument 1 is slow and redundant.\n"
"[test.cpp:15]: (performance) Passing the result of c_str() to a function that takes std::string as argument 2 is slow and redundant.\n", errout.str());
check("void Foo1(const std::string& str) {}\n"
"void Foo2(char* c, const std::string str) {}\n"
"void Bar() {\n"
" std::string str = \"bar\";\n"
" Foo1(str, foo);\n" // Don't crash
" Foo2(str.c_str());\n" // Don't crash
"}");
ASSERT_EQUALS("", errout.str());
check("struct Foo {\n"
" void func(std::string str) const {}\n"
" static void sfunc(std::string str) {}\n"
"};\n"
"void func(std::string str) {}\n"
"void Bar() {\n"
" std::string str = \"bar\";\n"
" Foo foo;\n"
" func(str.c_str());\n"
" Foo::sfunc(str.c_str());\n"
" foo.func(str.c_str());\n"
"}");
TODO_ASSERT_EQUALS("[test.cpp:9]: (performance) Passing the result of c_str() to a function that takes std::string as argument 1 is slow and redundant.\n"
"[test.cpp:10]: (performance) Passing the result of c_str() to a function that takes std::string as argument 1 is slow and redundant.\n",
"", errout.str());
check("void Foo(const char* p) {}\n"
"void Foo(const std::string& str) {Foo(str.c_str());}\n" // Overloaded
"void Bar() {\n"
" std::string str = \"bar\";\n"
" Foo(str);\n"
" Foo(str.c_str());\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void autoPointer() {