cppcheck/lib/checkexceptionsafety.h

180 lines
7.9 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2015 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/>.
*/
//---------------------------------------------------------------------------
#ifndef checkexceptionsafetyH
#define checkexceptionsafetyH
//---------------------------------------------------------------------------
#include "config.h"
#include "check.h"
/// @addtogroup Checks
/// @{
/**
* @brief %Check exception safety (exceptions shouldn't cause leaks nor corrupt data)
*
* The problem with these checks is that Cppcheck can't determine what the valid
* values are for variables. But in some cases (dead pointers) it can be determined
* that certain variable values are corrupt.
*/
class CPPCHECKLIB CheckExceptionSafety : public Check {
public:
/** This constructor is used when registering the CheckClass */
CheckExceptionSafety() : Check(myName()) {
}
/** This constructor is used when running checks. */
CheckExceptionSafety(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
: Check(myName(), tokenizer, settings, errorLogger) {
}
/** Checks that uses the simplified token list */
void runSimplifiedChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) {
if (tokenizer->isC())
return;
CheckExceptionSafety checkExceptionSafety(tokenizer, settings, errorLogger);
checkExceptionSafety.destructors();
checkExceptionSafety.deallocThrow();
checkExceptionSafety.checkRethrowCopy();
checkExceptionSafety.checkCatchExceptionByValue();
checkExceptionSafety.nothrowThrows();
checkExceptionSafety.unhandledExceptionSpecification();
}
/** Don't throw exceptions in destructors */
void destructors();
/** deallocating memory and then throw (dead pointer) */
void deallocThrow();
/** Don't rethrow a copy of the caught exception; use a bare throw instead */
void checkRethrowCopy();
/** @brief %Check for exceptions that are caught by value instead of by reference */
void checkCatchExceptionByValue();
/** @brief %Check for functions that throw that shouldn't */
void nothrowThrows();
/** @brief %Check for unhandled exception specification */
void unhandledExceptionSpecification();
private:
/** Don't throw exceptions in destructors */
void destructorsError(const Token * const tok, const std::string &className) {
reportError(tok, Severity::warning, "exceptThrowInDestructor",
"Class " + className + " is not safe, destructor throws exception\n"
"The class " + className + " is not safe because its destructor "
"throws an exception. If " + className + " is used and an exception "
"is thrown that is caught in an outer scope the program will terminate.");
}
void deallocThrowError(const Token * const tok, const std::string &varname) {
reportError(tok, Severity::warning, "exceptDeallocThrow", "Exception thrown in invalid state, '" +
varname + "' points at deallocated memory.");
}
void rethrowCopyError(const Token * const tok, const std::string &varname) {
reportError(tok, Severity::style, "exceptRethrowCopy",
"Throwing a copy of the caught exception instead of rethrowing the original exception.\n"
"Rethrowing an exception with 'throw " + varname + ";' creates an unnecessary copy of '" + varname + "'. "
"To rethrow the caught exception without unnecessary copying or slicing, use a bare 'throw;'.");
}
void catchExceptionByValueError(const Token *tok) {
reportError(tok, Severity::style,
"catchExceptionByValue", "Exception should be caught by reference.\n"
"The exception is caught by value. It could be caught "
"as a (const) reference which is usually recommended in C++.");
}
/** Don't throw exceptions in noexcept functions */
void noexceptThrowError(const Token * const tok) {
reportError(tok, Severity::error, "exceptThrowInNoexecptFunction", "Exception thrown in noexcept function.");
}
/** Don't throw exceptions in throw() functions */
void nothrowThrowError(const Token * const tok) {
reportError(tok, Severity::error, "exceptThrowInNoThrowFunction", "Exception thrown in throw() function.");
}
/** Don't throw exceptions in __attribute__((nothrow)) functions */
void nothrowAttributeThrowError(const Token * const tok) {
reportError(tok, Severity::error, "exceptThrowInAttributeNoThrowFunction", "Exception thrown in __attribute__((nothrow)) function.");
}
/** Don't throw exceptions in __declspec(nothrow) functions */
void nothrowDeclspecThrowError(const Token * const tok) {
reportError(tok, Severity::error, "exceptThrowInDeclspecNoThrowFunction", "Exception thrown in __declspec(nothrow) function.");
}
/** Missing exception specification */
void unhandledExceptionSpecificationError(const Token * const tok1, const Token * const tok2, const std::string & funcname) {
std::string str1(tok1 ? tok1->str() : "foo");
std::list<const Token*> locationList;
locationList.push_back(tok1);
locationList.push_back(tok2);
reportError(locationList, Severity::style, "unhandledExceptionSpecification",
"Unhandled exception specification when calling function " + str1 + "().\n"
"Unhandled exception specification when calling function " + str1 + "(). "
"Either use a try/catch around the function call, or add a exception specification for " + funcname + "() also.", true);
}
/** Generate all possible errors (for --errorlist) */
void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const {
CheckExceptionSafety c(0, settings, errorLogger);
c.destructorsError(0, "Class");
c.deallocThrowError(0, "p");
c.rethrowCopyError(0, "varname");
c.catchExceptionByValueError(0);
c.noexceptThrowError(0);
c.nothrowThrowError(0);
c.nothrowAttributeThrowError(0);
c.nothrowDeclspecThrowError(0);
c.unhandledExceptionSpecificationError(0, 0, "funcname");
}
/** Short description of class (for --doc) */
static std::string myName() {
return "Exception Safety";
}
/** wiki formatted description of the class (for --doc) */
std::string classInfo() const {
return "Checking exception safety\n"
"- Throwing exceptions in destructors\n"
"- Throwing exception during invalid state\n"
"- Throwing a copy of a caught exception instead of rethrowing the original exception\n"
"- Exception caught by value instead of by reference\n"
"- Throwing exception in noexcept function\n"
"- Throwing exception in nothrow() function\n"
"- Throwing exception in __attribute__((nothrow)) function\n"
"- Throwing exception in __declspec(nothrow) function\n"
"- Unhandled exception specification when calling function foo()\n";
}
};
/// @}
//---------------------------------------------------------------------------
#endif // checkexceptionsafetyH