cppcheck/lib/checkother.h

402 lines
19 KiB
C++

/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2018 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 "check.h"
#include "config.h"
#include "valueflow.h"
#include <cstddef>
#include <string>
#include <vector>
class ErrorLogger;
class Settings;
class Token;
class Tokenizer;
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) override {
CheckOther checkOther(tokenizer, settings, errorLogger);
// Checks
checkOther.warningOldStylePointerCast();
checkOther.invalidPointerCast();
checkOther.checkCharVariable();
checkOther.checkRedundantAssignment();
checkOther.checkRedundantAssignmentInSwitch();
checkOther.checkSuspiciousCaseInSwitch();
checkOther.checkDuplicateBranch();
checkOther.checkDuplicateExpression();
checkOther.checkUnreachableCode();
checkOther.checkSuspiciousSemicolon();
checkOther.checkVariableScope();
checkOther.checkSignOfUnsignedVariable(); // don't ignore casts (#3574)
checkOther.checkIncompleteArrayFill();
checkOther.checkVarFuncNullUB();
checkOther.checkNanInArithmeticExpression();
checkOther.checkCommaSeparatedReturn();
checkOther.checkRedundantPointerOp();
checkOther.checkZeroDivision();
checkOther.checkNegativeBitwiseShift();
checkOther.checkInterlockedDecrement();
checkOther.checkUnusedLabel();
checkOther.checkEvaluationOrder();
checkOther.checkFuncArgNamesDifferent();
checkOther.checkShadowVariables();
}
/** @brief Run checks against the simplified token list */
void runSimplifiedChecks(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger) override {
CheckOther checkOther(tokenizer, settings, errorLogger);
// Checks
checkOther.clarifyCalculation();
checkOther.clarifyStatement();
checkOther.checkPassByReference();
checkOther.checkIncompleteStatement();
checkOther.checkCastIntToCharAndBack();
checkOther.checkMisusedScopedObject();
checkOther.checkPipeParameterSize();
checkOther.checkInvalidFree();
checkOther.checkRedundantCopy();
checkOther.checkSuspiciousEqualityComparison();
checkOther.checkComparisonFunctionIsAlwaysTrueOrFalse();
checkOther.checkAccessOfMovedVariable();
}
/** @brief Clarify calculation for ".. a * b ? .." */
void clarifyCalculation();
/** @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 %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 function parameters that should be passed by reference */
void checkPassByReference();
/** @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 %Check zero division*/
void checkZeroDivision();
/** @brief Check for NaN (not-a-number) in an arithmetic expression */
void checkNanInArithmeticExpression();
/** @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 objects that are destroyed immediately */
void checkMisusedScopedObject();
/** @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 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 code creating redundant copies */
void checkRedundantCopy();
/** @brief %Check for bitwise shift 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();
/** @brief %Check for redundant pointer operations */
void checkRedundantPointerOp();
/** @brief %Check for race condition with non-interlocked access after InterlockedDecrement() */
void checkInterlockedDecrement();
/** @brief %Check for unused labels */
void checkUnusedLabel();
/** @brief %Check for expression that depends on order of evaluation of side effects */
void checkEvaluationOrder();
/** @brief %Check for access of moved or forwarded variable */
void checkAccessOfMovedVariable();
/** @brief %Check if function declaration and definition argument names different */
void checkFuncArgNamesDifferent();
/** @brief %Check for shadow variables. Less noisy than gcc/clang -Wshadow. */
void checkShadowVariables();
private:
// Error messages..
void checkComparisonFunctionIsAlwaysTrueOrFalseError(const Token* tok, const std::string &functionName, 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 clarifyCalculationError(const Token *tok, const std::string &op);
void clarifyStatementError(const Token* tok);
void cstyleCastError(const Token *tok);
void invalidPointerCastError(const Token* tok, const std::string& from, const std::string& to, bool inconclusive);
void passedByValueError(const Token *tok, const std::string &parname, bool inconclusive);
void constStatementError(const Token *tok, const std::string &type);
void signedCharArrayIndexError(const Token *tok);
void unknownSignCharArrayIndexError(const Token *tok);
void charBitOpError(const Token *tok);
void variableScopeError(const Token *tok, const std::string &varname);
void zerodivError(const Token *tok, const ValueFlow::Value *value);
void nanInArithmeticExpressionError(const Token *tok);
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 suspiciousCaseInSwitchError(const Token* tok, const std::string& operatorString);
void suspiciousEqualityComparisonError(const Token* tok);
void selfAssignmentError(const Token *tok, const std::string &varname);
void misusedScopeObjectError(const Token *tok, const std::string &varname);
void duplicateBranchError(const Token *tok1, const Token *tok2);
void duplicateAssignExpressionError(const Token *tok1, const Token *tok2, bool inconclusive);
void oppositeExpressionError(const Token *opTok, ErrorPath errors);
void duplicateExpressionError(const Token *tok1, const Token *tok2, const Token *opTok, ErrorPath errors);
void duplicateValueTernaryError(const Token *tok);
void duplicateExpressionTernaryError(const Token *tok, ErrorPath errors);
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 negativeBitwiseShiftError(const Token *tok, int op);
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 redundantPointerOpError(const Token* tok, const std::string& varname, bool inconclusive);
void raceAfterInterlockedDecrementError(const Token* tok);
void unusedLabelError(const Token* tok, bool inSwitch);
void unknownEvaluationOrder(const Token* tok);
static bool isMovedParameterAllowedForInconclusiveFunction(const Token * tok);
void accessMovedError(const Token *tok, const std::string &varname, const ValueFlow::Value *value, bool inconclusive);
void funcArgNamesDifferent(const std::string & functionName, size_t index, const Token* declaration, const Token* definition);
void funcArgOrderDifferent(const std::string & functionName, const Token * declaration, const Token * definition, const std::vector<const Token*> & declarations, const std::vector<const Token*> & definitions);
void shadowVariablesError(const Token *var, const Token *shadowed);
void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const override {
CheckOther c(nullptr, settings, errorLogger);
ErrorPath errorPath;
// error
c.zerodivError(nullptr, nullptr);
c.misusedScopeObjectError(nullptr, "varname");
c.invalidPointerCastError(nullptr, "float", "double", false);
c.negativeBitwiseShiftError(nullptr, 1);
c.negativeBitwiseShiftError(nullptr, 2);
c.checkPipeParameterSizeError(nullptr, "varname", "dimension");
c.raceAfterInterlockedDecrementError(nullptr);
c.invalidFreeError(nullptr, false);
//performance
c.redundantCopyError(nullptr, "varname");
c.redundantCopyError(nullptr, nullptr, "var");
c.redundantAssignmentError(nullptr, nullptr, "var", false);
// style/warning
c.checkComparisonFunctionIsAlwaysTrueOrFalseError(nullptr, "isless","varName",false);
c.checkCastIntToCharAndBackError(nullptr, "func_name");
c.cstyleCastError(nullptr);
c.passedByValueError(nullptr, "parametername", false);
c.constStatementError(nullptr, "type");
c.signedCharArrayIndexError(nullptr);
c.unknownSignCharArrayIndexError(nullptr);
c.charBitOpError(nullptr);
c.variableScopeError(nullptr, "varname");
c.redundantAssignmentInSwitchError(nullptr, nullptr, "var");
c.redundantCopyInSwitchError(nullptr, nullptr, "var");
c.suspiciousCaseInSwitchError(nullptr, "||");
c.suspiciousEqualityComparisonError(nullptr);
c.selfAssignmentError(nullptr, "varname");
c.clarifyCalculationError(nullptr, "+");
c.clarifyStatementError(nullptr);
c.duplicateBranchError(nullptr, nullptr);
c.duplicateAssignExpressionError(nullptr, nullptr, true);
c.oppositeExpressionError(nullptr, errorPath);
c.duplicateExpressionError(nullptr, nullptr, nullptr, errorPath);
c.duplicateValueTernaryError(nullptr);
c.duplicateExpressionTernaryError(nullptr, errorPath);
c.duplicateBreakError(nullptr, false);
c.unreachableCodeError(nullptr, false);
c.unsignedLessThanZeroError(nullptr, "varname", false);
c.unsignedPositiveError(nullptr, "varname", false);
c.pointerLessThanZeroError(nullptr, false);
c.pointerPositiveError(nullptr, false);
c.SuspiciousSemicolonError(nullptr);
c.incompleteArrayFillError(nullptr, "buffer", "memset", false);
c.varFuncNullUBError(nullptr);
c.nanInArithmeticExpressionError(nullptr);
c.commaSeparatedReturnError(nullptr);
c.redundantPointerOpError(nullptr, "varname", false);
c.unusedLabelError(nullptr, true);
c.unusedLabelError(nullptr, false);
c.unknownEvaluationOrder(nullptr);
c.accessMovedError(nullptr, "v", nullptr, false);
c.funcArgNamesDifferent("function", 1, nullptr, nullptr);
c.redundantBitwiseOperationInSwitchError(nullptr, "varname");
c.shadowVariablesError(nullptr, nullptr);
const std::vector<const Token *> nullvec;
c.funcArgOrderDifferent("function", nullptr, nullptr, nullvec, nullvec);
}
static std::string myName() {
return "Other";
}
std::string classInfo() const override {
return "Other checks\n"
// error
"- division with zero\n"
"- scoped object destroyed immediately after construction\n"
"- assignment in an assert statement\n"
"- free() or delete of an invalid memory location\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"
"- race condition with non-interlocked access after InterlockedDecrement() call\n"
"- expression 'x = x++;' depends on order of evaluation of side effects\n"
// warning
"- either division by zero or useless condition\n"
"- access of moved or forwarded variable.\n"
// performance
"- redundant data copying for const variable\n"
"- subsequent assignment or copying to a variable or buffer\n"
"- passing parameter by value\n"
// portability
"- Passing NULL pointer to function with variable number of arguments leads to UB.\n"
// style
"- C-style pointer cast in C++ code\n"
"- casting between incompatible pointer types\n"
"- [Incomplete statement](IncompleteStatement)\n"
"- [check how signed char variables are used](CharVar)\n"
"- variable scope can be limited\n"
"- unusual pointer arithmetic. For example: \"abc\" + 'd'\n"
"- redundant assignment, increment, or bitwise operation in a switch statement\n"
"- redundant strcpy in a switch statement\n"
"- Suspicious case labels in switch()\n"
"- assignment of a variable to itself\n"
"- Comparison of values leading always to true or false\n"
"- Clarify calculation with parentheses\n"
"- suspicious comparison of '\\0' with a char\\* variable\n"
"- duplicate break statement\n"
"- unreachable code\n"
"- testing if unsigned variable is negative/positive\n"
"- Suspicious use of ; at the end of 'if/for/while' statement.\n"
"- Array filled incompletely using memset/memcpy/memmove.\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"
"- prefer erfc, expm1 or log1p to avoid loss of precision.\n"
"- identical code in both branches of if/else or ternary operator.\n"
"- redundant pointer operation on pointer like &\\*some_ptr.\n"
"- find unused 'goto' labels.\n"
"- function declaration and definition argument names different.\n"
"- function declaration and definition argument order different.\n"
"- shadow variable.\n";
}
};
/// @}
//---------------------------------------------------------------------------
#endif // checkotherH