cppcheck/lib/checkother.h

465 lines
21 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2014 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 checkotherH
#define checkotherH
//---------------------------------------------------------------------------
#include "config.h"
#include "check.h"
#include "settings.h"
class Token;
class Function;
class Variable;
/// @addtogroup Checks
/// @{
/** @brief Various small checks */
class CPPCHECKLIB CheckOther : public Check {
public:
/** @brief This constructor is used when registering the CheckClass */
CheckOther() : Check(myName()) {
}
/** @brief This constructor is used when running checks. */
CheckOther(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
: Check(myName(), tokenizer, settings, errorLogger) {
}
/** @brief Run checks against the normal token list */
void runChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) {
CheckOther checkOther(tokenizer, settings, errorLogger);
// Checks
checkOther.warningOldStylePointerCast();
checkOther.invalidPointerCast();
checkOther.checkUnsignedDivision();
checkOther.checkCharVariable();
checkOther.strPlusChar();
checkOther.checkRedundantAssignment();
checkOther.checkRedundantAssignmentInSwitch();
checkOther.checkSuspiciousCaseInSwitch();
checkOther.checkSelfAssignment();
checkOther.checkDuplicateIf();
checkOther.checkDuplicateBranch();
checkOther.checkDuplicateExpression();
checkOther.checkUnreachableCode();
checkOther.checkSuspiciousSemicolon();
checkOther.checkVariableScope();
checkOther.clarifyCondition(); // not simplified because ifAssign
checkOther.checkSignOfUnsignedVariable(); // don't ignore casts (#3574)
checkOther.checkIncompleteArrayFill();
checkOther.checkSuspiciousStringCompare();
checkOther.checkVarFuncNullUB();
checkOther.checkNanInArithmeticExpression();
checkOther.checkCommaSeparatedReturn();
}
/** @brief Run checks against the simplified token list */
void runSimplifiedChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) {
CheckOther checkOther(tokenizer, settings, errorLogger);
// Checks
checkOther.oppositeInnerCondition();
checkOther.clarifyCalculation();
checkOther.clarifyStatement();
checkOther.checkConstantFunctionParameter();
checkOther.checkIncompleteStatement();
checkOther.checkCastIntToCharAndBack();
checkOther.invalidFunctionUsage();
checkOther.checkZeroDivision();
checkOther.checkMathFunctions();
checkOther.redundantGetAndSetUserId();
checkOther.checkIncorrectLogicOperator();
checkOther.checkMisusedScopedObject();
checkOther.checkMemsetZeroBytes();
checkOther.checkIncorrectStringCompare();
checkOther.checkSwitchCaseFallThrough();
checkOther.checkAlwaysTrueOrFalseStringCompare();
checkOther.checkModuloAlwaysTrueFalse();
checkOther.checkPipeParameterSize();
checkOther.checkInvalidFree();
checkOther.checkDoubleFree();
checkOther.checkRedundantCopy();
checkOther.checkNegativeBitwiseShift();
checkOther.checkSuspiciousEqualityComparison();
checkOther.checkComparisonFunctionIsAlwaysTrueOrFalse();
}
/** To check the dead code in a program, which is inaccessible due to the counter-conditions check in nested-if statements **/
void oppositeInnerCondition();
/** @brief Clarify calculation for ".. a * b ? .." */
void clarifyCalculation();
/** @brief Suspicious condition (assignment+comparison) */
void clarifyCondition();
/** @brief Suspicious statement like '*A++;' */
void clarifyStatement();
/** @brief Are there C-style pointer casts in a c++ file? */
void warningOldStylePointerCast();
/** @brief Check for pointer casts to a type with an incompatible binary data representation */
void invalidPointerCast();
/**
* @brief Invalid function usage (invalid input value / overlapping data)
*
* %Check that given function parameters are valid according to the standard
* - wrong radix given for strtol/strtoul
* - overlapping data when using sprintf/snprintf
* - wrong input value according to library
*/
void invalidFunctionUsage();
/** @brief %Check for unsigned division */
void checkUnsignedDivision();
/** @brief %Check scope of variables */
void checkVariableScope();
static bool checkInnerScope(const Token *tok, const Variable* var, bool& used);
/** @brief %Check for comma separated statements in return */
void checkCommaSeparatedReturn();
/** @brief %Check for constant function parameter */
void checkConstantFunctionParameter();
/** @brief Using char variable as array index / as operand in bit operation */
void checkCharVariable();
/** @brief Incomplete statement. A statement that only contains a constant or variable */
void checkIncompleteStatement();
/** @brief str plus char (unusual pointer arithmetic) */
void strPlusChar();
/** @brief %Check zero division*/
void checkZeroDivision();
/** @brief %Check zero division / useless condition */
void checkZeroDivisionOrUselessCondition();
/** @brief Check for NaN (not-a-number) in an arithmetic expression */
void checkNanInArithmeticExpression();
/** @brief %Check for parameters given to math function that do not make sense*/
void checkMathFunctions();
/** @brief % Check for seteuid(geteuid()) or setuid(getuid())*/
void redundantGetAndSetUserId();
/** @brief copying to memory or assigning to a variable twice */
void checkRedundantAssignment();
/** @brief %Check for assigning to the same variable twice in a switch statement*/
void checkRedundantAssignmentInSwitch();
/** @brief %Check for code like 'case A||B:'*/
void checkSuspiciousCaseInSwitch();
/** @brief %Check for code like 'case A||B:'*/
void checkSuspiciousEqualityComparison();
/** @brief %Check for switch case fall through without comment */
void checkSwitchCaseFallThrough();
/** @brief %Check for assigning a variable to itself*/
void checkSelfAssignment();
/** @brief %Check for testing for mutual exclusion over ||*/
void checkIncorrectLogicOperator();
/** @brief %Check for objects that are destroyed immediately */
void checkMisusedScopedObject();
/** @brief %Check for filling zero bytes with memset() */
void checkMemsetZeroBytes();
/** @brief %Check for using bad usage of strncmp and substr */
void checkIncorrectStringCompare();
/** @brief %Check for comparison of a string literal with a char* variable */
void checkSuspiciousStringCompare();
/** @brief %Check for suspicious code where multiple if have the same expression (e.g "if (a) { } else if (a) { }") */
void checkDuplicateIf();
/** @brief %Check for suspicious code where if and else branch are the same (e.g "if (a) b = true; else b = true;") */
void checkDuplicateBranch();
/** @brief %Check for suspicious code with the same expression on both sides of operator (e.g "if (a && a)") */
void checkDuplicateExpression();
/** @brief %Check for suspicious code that compares string literals for equality */
void checkAlwaysTrueOrFalseStringCompare();
/** @brief %Check for suspicious usage of modulo (e.g. "if(var % 4 == 4)") */
void checkModuloAlwaysTrueFalse();
/** @brief %Check for code that gets never executed, such as duplicate break statements */
void checkUnreachableCode();
/** @brief %Check for testing sign of unsigned variable */
void checkSignOfUnsignedVariable();
/** @brief %Check for suspicious use of semicolon */
void checkSuspiciousSemicolon();
/** @brief %Check for free() operations on invalid memory locations */
void checkInvalidFree();
void invalidFreeError(const Token *tok, bool inconclusive);
/** @brief %Check for double free or double close operations */
void checkDoubleFree();
void doubleFreeError(const Token *tok, const std::string &varname);
/** @brief %Check for code creating redundant copies */
void checkRedundantCopy();
/** @brief %Check for bitwise operation with negative right operand */
void checkNegativeBitwiseShift();
/** @brief %Check for buffers that are filled incompletely with memset and similar functions */
void checkIncompleteArrayFill();
/** @brief %Check that variadic function calls don't use NULL. If NULL is \#defined as 0 and the function expects a pointer, the behaviour is undefined. */
void checkVarFuncNullUB();
/** @brief %Check that calling the POSIX pipe() system call is called with an integer array of size two. */
void checkPipeParameterSize();
/** @brief %Check to avoid casting a return value to unsigned char and then back to integer type. */
void checkCastIntToCharAndBack();
/** @brief %Check for using of comparison functions evaluating always to true or false. */
void checkComparisonFunctionIsAlwaysTrueOrFalse(void);
private:
bool isUnsigned(const Variable *var) const;
static bool isSigned(const Variable *var);
// Error messages..
void checkComparisonFunctionIsAlwaysTrueOrFalseError(const Token* tok, const std::string &strFunctionName, const std::string &varName, const bool result);
void checkCastIntToCharAndBackError(const Token *tok, const std::string &strFunctionName);
void checkPipeParameterSizeError(const Token *tok, const std::string &strVarName, const std::string &strDim);
void oppositeInnerConditionError(const Token *tok);
void clarifyCalculationError(const Token *tok, const std::string &op);
void clarifyConditionError(const Token *tok, bool assign, bool boolop);
void clarifyStatementError(const Token* tok);
void redundantGetAndSetUserIdError(const Token *tok);
void cstyleCastError(const Token *tok);
void invalidPointerCastError(const Token* tok, const std::string& from, const std::string& to, bool inconclusive);
void sprintfOverlappingDataError(const Token *tok, const std::string &varname);
void invalidFunctionArgError(const Token *tok, const std::string &functionName, int argnr, const std::string &validstr);
void invalidFunctionArgBoolError(const Token *tok, const std::string &functionName, int argnr);
void udivError(const Token *tok, bool inconclusive);
void passedByValueError(const Token *tok, const std::string &parname);
void constStatementError(const Token *tok, const std::string &type);
void charArrayIndexError(const Token *tok);
void charBitOpError(const Token *tok);
void variableScopeError(const Token *tok, const std::string &varname);
void strPlusCharError(const Token *tok);
void zerodivError(const Token *tok);
void zerodivcondError(const Token *tokcond, const Token *tokdiv);
void nanInArithmeticExpressionError(const Token *tok);
void mathfunctionCallError(const Token *tok, const unsigned int numParam = 1);
void redundantAssignmentError(const Token *tok1, const Token* tok2, const std::string& var, bool inconclusive);
void redundantAssignmentInSwitchError(const Token *tok1, const Token *tok2, const std::string &var);
void redundantCopyError(const Token *tok1, const Token* tok2, const std::string& var);
void redundantCopyInSwitchError(const Token *tok1, const Token* tok2, const std::string &var);
void redundantBitwiseOperationInSwitchError(const Token *tok, const std::string &varname);
void switchCaseFallThrough(const Token *tok);
void suspiciousCaseInSwitchError(const Token* tok, const std::string& operatorString);
void suspiciousEqualityComparisonError(const Token* tok);
void selfAssignmentError(const Token *tok, const std::string &varname);
void incorrectLogicOperatorError(const Token *tok, const std::string &condition, bool always);
void redundantConditionError(const Token *tok, const std::string &text);
void misusedScopeObjectError(const Token *tok, const std::string &varname);
void memsetZeroBytesError(const Token *tok, const std::string &varname);
void incorrectStringCompareError(const Token *tok, const std::string& func, const std::string &string);
void incorrectStringBooleanError(const Token *tok, const std::string& string);
void duplicateIfError(const Token *tok1, const Token *tok2);
void duplicateBranchError(const Token *tok1, const Token *tok2);
void duplicateExpressionError(const Token *tok1, const Token *tok2, const std::string &op);
void alwaysTrueFalseStringCompareError(const Token *tok, const std::string& str1, const std::string& str2);
void alwaysTrueStringVariableCompareError(const Token *tok, const std::string& str1, const std::string& str2);
void suspiciousStringCompareError(const Token* tok, const std::string& var);
void duplicateBreakError(const Token *tok, bool inconclusive);
void unreachableCodeError(const Token* tok, bool inconclusive);
void unsignedLessThanZeroError(const Token *tok, const std::string &varname, bool inconclusive);
void pointerLessThanZeroError(const Token *tok, bool inconclusive);
void unsignedPositiveError(const Token *tok, const std::string &varname, bool inconclusive);
void pointerPositiveError(const Token *tok, bool inconclusive);
void SuspiciousSemicolonError(const Token *tok);
void doubleCloseDirError(const Token *tok, const std::string &varname);
void moduloAlwaysTrueFalseError(const Token* tok, const std::string& maxVal);
void negativeBitwiseShiftError(const Token *tok);
void redundantCopyError(const Token *tok, const std::string &varname);
void incompleteArrayFillError(const Token* tok, const std::string& buffer, const std::string& function, bool boolean);
void varFuncNullUBError(const Token *tok);
void commaSeparatedReturnError(const Token *tok);
void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const {
CheckOther c(0, settings, errorLogger);
// error
c.sprintfOverlappingDataError(0, "varname");
c.invalidFunctionArgError(0, "func_name", 1, "1-4");
c.invalidFunctionArgBoolError(0, "func_name", 1);
c.udivError(0, false);
c.zerodivError(0);
c.zerodivcondError(0,0);
c.mathfunctionCallError(0);
c.misusedScopeObjectError(NULL, "varname");
c.doubleFreeError(0, "varname");
c.invalidPointerCastError(0, "float", "double", false);
c.negativeBitwiseShiftError(0);
c.checkPipeParameterSizeError(0, "varname", "dimension");
//performance
c.redundantCopyError(0, "varname");
c.redundantCopyError(0, 0, "var");
c.redundantAssignmentError(0, 0, "var", false);
// style/warning
c.checkComparisonFunctionIsAlwaysTrueOrFalseError(0,"isless","varName",false);
c.checkCastIntToCharAndBackError(0,"func_name");
c.oppositeInnerConditionError(0);
c.cstyleCastError(0);
c.passedByValueError(0, "parametername");
c.constStatementError(0, "type");
c.charArrayIndexError(0);
c.charBitOpError(0);
c.variableScopeError(0, "varname");
c.strPlusCharError(0);
c.redundantAssignmentInSwitchError(0, 0, "var");
c.redundantCopyInSwitchError(0, 0, "var");
c.switchCaseFallThrough(0);
c.suspiciousCaseInSwitchError(0, "||");
c.suspiciousEqualityComparisonError(0);
c.selfAssignmentError(0, "varname");
c.incorrectLogicOperatorError(0, "foo > 3 && foo < 4", true);
c.redundantConditionError(0, "If x > 10 the condition x > 11 is always true.");
c.memsetZeroBytesError(0, "varname");
c.clarifyCalculationError(0, "+");
c.clarifyConditionError(0, true, false);
c.clarifyStatementError(0);
c.incorrectStringCompareError(0, "substr", "\"Hello World\"");
c.suspiciousStringCompareError(0, "foo");
c.incorrectStringBooleanError(0, "\"Hello World\"");
c.duplicateIfError(0, 0);
c.duplicateBranchError(0, 0);
c.duplicateExpressionError(0, 0, "&&");
c.alwaysTrueFalseStringCompareError(0, "str1", "str2");
c.alwaysTrueStringVariableCompareError(0, "varname1", "varname2");
c.duplicateBreakError(0, false);
c.unreachableCodeError(0, false);
c.unsignedLessThanZeroError(0, "varname", false);
c.unsignedPositiveError(0, "varname", false);
c.pointerLessThanZeroError(0, false);
c.pointerPositiveError(0, false);
c.SuspiciousSemicolonError(0);
c.moduloAlwaysTrueFalseError(0, "1");
c.incompleteArrayFillError(0, "buffer", "memset", false);
c.varFuncNullUBError(0);
c.nanInArithmeticExpressionError(0);
c.commaSeparatedReturnError(0);
}
static std::string myName() {
return "Other";
}
std::string classInfo() const {
return "Other checks\n"
// error
"* Assigning bool value to pointer (converting bool value to address)\n"
"* division with zero\n"
"* scoped object destroyed immediately after construction\n"
"* assignment in an assert statement\n"
"* incorrect length arguments for 'substr' and 'strncmp'\n"
"* free() or delete of an invalid memory location\n"
"* double free() or double closedir()\n"
"* bitwise operation with negative right operand\n"
"* provide wrong dimensioned array to pipe() system command (--std=posix)\n"
"* cast the return values of getc(),fgetc() and getchar() to character and compare it to EOF\n"
"* invalid input values for functions\n"
// warning
"* either division by zero or useless condition\n"
//performance
"* redundant data copying for const variable\n"
"* subsequent assignment or copying to a variable or buffer\n"
// style
"* Find dead code which is inaccessible due to the counter-conditions check in nested if statements\n"
"* C-style pointer cast in cpp file\n"
"* casting between incompatible pointer types\n"
"* redundant if\n"
"* [[CheckUnsignedDivision|unsigned division]]\n"
"* passing parameter by value\n"
"* [[IncompleteStatement|Incomplete statement]]\n"
"* [[charvar|check how signed char variables are used]]\n"
"* variable scope can be limited\n"
"* condition that is always true/false\n"
"* unusual pointer arithmetic. For example: \"abc\" + 'd'\n"
"* redundant assignment in a switch statement\n"
"* redundant pre/post operation in a switch statement\n"
"* redundant bitwise operation in a switch statement\n"
"* redundant strcpy in a switch statement\n"
"* assignment of a variable to itself\n"
"* Suspicious case labels in switch()\n"
"* Suspicious equality comparisons\n"
"* mutual exclusion over || always evaluating to true\n"
"* Comparison of values leading always to true or false\n"
"* Clarify calculation with parentheses\n"
"* suspicious condition (assignment+comparison)\n"
"* suspicious condition (runtime comparison of string literals)\n"
"* suspicious condition (string literals as boolean)\n"
"* suspicious comparison of a string literal with a char* variable\n"
"* duplicate break statement\n"
"* unreachable code\n"
"* testing if unsigned variable is negative\n"
"* testing is unsigned variable is positive\n"
"* Suspicious use of ; at the end of 'if/for/while' statement.\n"
"* Comparisons of modulo results that are always true/false.\n"
"* Array filled incompletely using memset/memcpy/memmove.\n"
"* redundant get and set function of user id (--std=posix).\n"
"* Passing NULL pointer to function with variable number of arguments leads to UB on some platforms.\n"
"* NaN (not a number) value used in arithmetic expression.\n"
"* comma in return statement (the comma can easily be misread as a semicolon).\n";
}
};
/// @}
//---------------------------------------------------------------------------
#endif // checkotherH