468 lines
18 KiB
C++
468 lines
18 KiB
C++
/*
|
|
* Cppcheck - A tool for static C/C++ code analysis
|
|
* Copyright (C) 2007-2023 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 "checkunusedfunctions.h"
|
|
|
|
#include "astutils.h"
|
|
#include "errorlogger.h"
|
|
#include "errortypes.h"
|
|
#include "library.h"
|
|
#include "settings.h"
|
|
#include "symboldatabase.h"
|
|
#include "token.h"
|
|
#include "tokenize.h"
|
|
#include "tokenlist.h"
|
|
#include "utils.h"
|
|
|
|
#include <algorithm>
|
|
#include <cctype>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <fstream> // IWYU pragma: keep
|
|
#include <map>
|
|
#include <sstream> // IWYU pragma: keep
|
|
#include <tuple>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include <tinyxml2.h>
|
|
|
|
namespace CTU {
|
|
class FileInfo;
|
|
}
|
|
|
|
//---------------------------------------------------------------------------
|
|
|
|
|
|
|
|
// Register this check class
|
|
CheckUnusedFunctions CheckUnusedFunctions::instance;
|
|
|
|
static const struct CWE CWE561(561U); // Dead Code
|
|
|
|
static std::string stripTemplateParameters(const std::string& funcName) {
|
|
std::string name = funcName;
|
|
const auto pos = name.find('<');
|
|
if (pos > 0 && pos != std::string::npos)
|
|
name.erase(pos - 1);
|
|
return name;
|
|
}
|
|
|
|
//---------------------------------------------------------------------------
|
|
// FUNCTION USAGE - Check for unused functions etc
|
|
//---------------------------------------------------------------------------
|
|
|
|
void CheckUnusedFunctions::parseTokens(const Tokenizer &tokenizer, const char FileName[], const Settings *settings)
|
|
{
|
|
const bool doMarkup = settings->library.markupFile(FileName);
|
|
|
|
// Function declarations..
|
|
if (!doMarkup) {
|
|
const SymbolDatabase* symbolDatabase = tokenizer.getSymbolDatabase();
|
|
for (const Scope* scope : symbolDatabase->functionScopes) {
|
|
const Function* func = scope->function;
|
|
if (!func || !func->token || scope->bodyStart->fileIndex() != 0)
|
|
continue;
|
|
|
|
// Don't warn about functions that are marked by __attribute__((constructor)) or __attribute__((destructor))
|
|
if (func->isAttributeConstructor() || func->isAttributeDestructor() || func->type != Function::eFunction || func->isOperator())
|
|
continue;
|
|
|
|
if (func->isExtern())
|
|
continue;
|
|
|
|
mFunctionDecl.emplace_back(func);
|
|
|
|
FunctionUsage &usage = mFunctions[stripTemplateParameters(func->name())];
|
|
|
|
if (!usage.lineNumber)
|
|
usage.lineNumber = func->token->linenr();
|
|
|
|
// No filename set yet..
|
|
if (usage.filename.empty()) {
|
|
usage.filename = tokenizer.list.getSourceFilePath();
|
|
}
|
|
// Multiple files => filename = "+"
|
|
else if (usage.filename != tokenizer.list.getSourceFilePath()) {
|
|
//func.filename = "+";
|
|
usage.usedOtherFile |= usage.usedSameFile;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Function usage..
|
|
const Token *lambdaEndToken = nullptr;
|
|
for (const Token *tok = tokenizer.tokens(); tok; tok = tok->next()) {
|
|
|
|
if (tok == lambdaEndToken)
|
|
lambdaEndToken = nullptr;
|
|
else if (!lambdaEndToken && tok->str() == "[")
|
|
lambdaEndToken = findLambdaEndToken(tok);
|
|
|
|
// parsing of library code to find called functions
|
|
if (settings->library.isexecutableblock(FileName, tok->str())) {
|
|
const Token * markupVarToken = tok->tokAt(settings->library.blockstartoffset(FileName));
|
|
// not found
|
|
if (!markupVarToken)
|
|
continue;
|
|
int scope = 0;
|
|
bool start = true;
|
|
// find all function calls in library code (starts with '(', not if or while etc)
|
|
while ((scope || start) && markupVarToken) {
|
|
if (markupVarToken->str() == settings->library.blockstart(FileName)) {
|
|
scope++;
|
|
start = false;
|
|
} else if (markupVarToken->str() == settings->library.blockend(FileName))
|
|
scope--;
|
|
else if (!settings->library.iskeyword(FileName, markupVarToken->str())) {
|
|
mFunctionCalls.insert(markupVarToken->str());
|
|
if (mFunctions.find(markupVarToken->str()) != mFunctions.end())
|
|
mFunctions[markupVarToken->str()].usedOtherFile = true;
|
|
else if (markupVarToken->next()->str() == "(") {
|
|
FunctionUsage &func = mFunctions[markupVarToken->str()];
|
|
func.filename = tokenizer.list.getSourceFilePath();
|
|
if (func.filename.empty() || func.filename == "+")
|
|
func.usedOtherFile = true;
|
|
else
|
|
func.usedSameFile = true;
|
|
}
|
|
}
|
|
markupVarToken = markupVarToken->next();
|
|
}
|
|
}
|
|
|
|
if (!doMarkup // only check source files
|
|
&& settings->library.isexporter(tok->str()) && tok->next() != nullptr) {
|
|
const Token * propToken = tok->next();
|
|
while (propToken && propToken->str() != ")") {
|
|
if (settings->library.isexportedprefix(tok->str(), propToken->str())) {
|
|
const Token* nextPropToken = propToken->next();
|
|
const std::string& value = nextPropToken->str();
|
|
if (mFunctions.find(value) != mFunctions.end()) {
|
|
mFunctions[value].usedOtherFile = true;
|
|
}
|
|
mFunctionCalls.insert(value);
|
|
}
|
|
if (settings->library.isexportedsuffix(tok->str(), propToken->str())) {
|
|
const Token* prevPropToken = propToken->previous();
|
|
const std::string& value = prevPropToken->str();
|
|
if (value != ")" && mFunctions.find(value) != mFunctions.end()) {
|
|
mFunctions[value].usedOtherFile = true;
|
|
}
|
|
mFunctionCalls.insert(value);
|
|
}
|
|
propToken = propToken->next();
|
|
}
|
|
}
|
|
|
|
if (doMarkup && settings->library.isimporter(FileName, tok->str()) && tok->next()) {
|
|
const Token * propToken = tok->next();
|
|
if (propToken->next()) {
|
|
propToken = propToken->next();
|
|
while (propToken && propToken->str() != ")") {
|
|
const std::string& value = propToken->str();
|
|
if (!value.empty()) {
|
|
mFunctions[value].usedOtherFile = true;
|
|
mFunctionCalls.insert(value);
|
|
break;
|
|
}
|
|
propToken = propToken->next();
|
|
}
|
|
}
|
|
}
|
|
|
|
if (settings->library.isreflection(tok->str())) {
|
|
const int argIndex = settings->library.reflectionArgument(tok->str());
|
|
if (argIndex >= 0) {
|
|
const Token * funcToken = tok->next();
|
|
int index = 0;
|
|
std::string value;
|
|
while (funcToken) {
|
|
if (funcToken->str()==",") {
|
|
if (++index == argIndex)
|
|
break;
|
|
value.clear();
|
|
} else
|
|
value += funcToken->str();
|
|
funcToken = funcToken->next();
|
|
}
|
|
if (index == argIndex) {
|
|
value = value.substr(1, value.length() - 2);
|
|
mFunctions[value].usedOtherFile = true;
|
|
mFunctionCalls.insert(std::move(value));
|
|
}
|
|
}
|
|
}
|
|
|
|
const Token *funcname = nullptr;
|
|
|
|
if (doMarkup)
|
|
funcname = Token::Match(tok, "%name% (") ? tok : nullptr;
|
|
else if ((lambdaEndToken || tok->scope()->isExecutable()) && Token::Match(tok, "%name% (")) {
|
|
funcname = tok;
|
|
} else if ((lambdaEndToken || tok->scope()->isExecutable()) && Token::Match(tok, "%name% <") && Token::simpleMatch(tok->linkAt(1), "> (")) {
|
|
funcname = tok;
|
|
} else if (Token::Match(tok, "< %name%") && tok->link()) {
|
|
funcname = tok->next();
|
|
while (Token::Match(funcname, "%name% :: %name%"))
|
|
funcname = funcname->tokAt(2);
|
|
} else if (tok->scope()->type != Scope::ScopeType::eEnum && (Token::Match(tok, "[;{}.,()[=+-/|!?:]") || Token::Match(tok, "return|throw"))) {
|
|
funcname = tok->next();
|
|
if (funcname && funcname->str() == "&")
|
|
funcname = funcname->next();
|
|
if (funcname && funcname->str() == "::")
|
|
funcname = funcname->next();
|
|
while (Token::Match(funcname, "%name% :: %name%"))
|
|
funcname = funcname->tokAt(2);
|
|
|
|
if (!Token::Match(funcname, "%name% [(),;]:}>]") || funcname->varId())
|
|
continue;
|
|
}
|
|
|
|
if (!funcname || funcname->isKeyword() || funcname->isStandardType())
|
|
continue;
|
|
|
|
// funcname ( => Assert that the end parentheses isn't followed by {
|
|
if (Token::Match(funcname, "%name% (|<")) {
|
|
const Token *ftok = funcname->next();
|
|
if (ftok->str() == "<")
|
|
ftok = ftok->link();
|
|
if (Token::Match(ftok->linkAt(1), ") const|throw|{"))
|
|
funcname = nullptr;
|
|
}
|
|
|
|
if (funcname) {
|
|
const auto baseName = stripTemplateParameters(funcname->str());
|
|
FunctionUsage &func = mFunctions[baseName];
|
|
const std::string& called_from_file = tokenizer.list.getSourceFilePath();
|
|
|
|
if (func.filename.empty() || func.filename == "+" || func.filename != called_from_file)
|
|
func.usedOtherFile = true;
|
|
else
|
|
func.usedSameFile = true;
|
|
|
|
mFunctionCalls.insert(baseName);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
static bool isOperatorFunction(const std::string & funcName)
|
|
{
|
|
/* Operator functions are invalid function names for C, so no need to check
|
|
* this in here. As result the returned error function might be incorrect.
|
|
*
|
|
* List of valid operators can be found at:
|
|
* http://en.cppreference.com/w/cpp/language/operators
|
|
*
|
|
* Conversion functions must be a member function (at least for gcc), so no
|
|
* need to cover them for unused functions.
|
|
*
|
|
* To speed up the comparison, not the whole list of operators is used.
|
|
* Instead only the character after the operator prefix is checked to be a
|
|
* none alpa numeric value, but the '_', to cover function names like
|
|
* "operator_unused". In addition the following valid operators are checked:
|
|
* - new
|
|
* - new[]
|
|
* - delete
|
|
* - delete[]
|
|
*/
|
|
const std::string operatorPrefix = "operator";
|
|
if (funcName.compare(0, operatorPrefix.length(), operatorPrefix) != 0) {
|
|
return false;
|
|
}
|
|
|
|
// Taking care of funcName == "operator", which is no valid operator
|
|
if (funcName.length() == operatorPrefix.length()) {
|
|
return false;
|
|
}
|
|
|
|
const char firstOperatorChar = funcName[operatorPrefix.length()];
|
|
if (firstOperatorChar == '_') {
|
|
return false;
|
|
}
|
|
|
|
if (!std::isalnum(firstOperatorChar)) {
|
|
return true;
|
|
}
|
|
|
|
const std::vector<std::string> additionalOperators = {
|
|
"new", "new[]", "delete", "delete[]"
|
|
};
|
|
|
|
|
|
return std::find(additionalOperators.cbegin(), additionalOperators.cend(), funcName.substr(operatorPrefix.length())) != additionalOperators.cend();
|
|
}
|
|
|
|
bool CheckUnusedFunctions::check(ErrorLogger * const errorLogger, const Settings& settings) const
|
|
{
|
|
using ErrorParams = std::tuple<std::string, unsigned int, std::string>;
|
|
std::vector<ErrorParams> errors; // ensure well-defined order
|
|
|
|
for (std::unordered_map<std::string, FunctionUsage>::const_iterator it = mFunctions.cbegin(); it != mFunctions.cend(); ++it) {
|
|
const FunctionUsage &func = it->second;
|
|
if (func.usedOtherFile || func.filename.empty())
|
|
continue;
|
|
if (settings.library.isentrypoint(it->first))
|
|
continue;
|
|
if (!func.usedSameFile) {
|
|
if (isOperatorFunction(it->first))
|
|
continue;
|
|
std::string filename;
|
|
if (func.filename != "+")
|
|
filename = func.filename;
|
|
errors.emplace_back(filename, func.lineNumber, it->first);
|
|
} else if (!func.usedOtherFile) {
|
|
/** @todo add error message "function is only used in <file> it can be static" */
|
|
/*
|
|
std::ostringstream errmsg;
|
|
errmsg << "The function '" << it->first << "' is only used in the file it was declared in so it should have local linkage.";
|
|
mErrorLogger->reportErr( errmsg.str() );
|
|
errors = true;
|
|
*/
|
|
}
|
|
}
|
|
std::sort(errors.begin(), errors.end());
|
|
for (const auto& e : errors)
|
|
unusedFunctionError(errorLogger, std::get<0>(e), std::get<1>(e), std::get<2>(e));
|
|
return !errors.empty();
|
|
}
|
|
|
|
void CheckUnusedFunctions::unusedFunctionError(ErrorLogger * const errorLogger,
|
|
const std::string &filename, unsigned int lineNumber,
|
|
const std::string &funcname)
|
|
{
|
|
std::list<ErrorMessage::FileLocation> locationList;
|
|
if (!filename.empty()) {
|
|
locationList.emplace_back(filename, lineNumber);
|
|
}
|
|
|
|
const ErrorMessage errmsg(locationList, emptyString, Severity::style, "$symbol:" + funcname + "\nThe function '$symbol' is never used.", "unusedFunction", CWE561, Certainty::normal);
|
|
if (errorLogger)
|
|
errorLogger->reportErr(errmsg);
|
|
else
|
|
reportError(errmsg);
|
|
}
|
|
|
|
Check::FileInfo *CheckUnusedFunctions::getFileInfo(const Tokenizer *tokenizer, const Settings *settings) const
|
|
{
|
|
if (!settings->checks.isEnabled(Checks::unusedFunction))
|
|
return nullptr;
|
|
if (settings->useSingleJob() && settings->buildDir.empty())
|
|
instance.parseTokens(*tokenizer, tokenizer->list.getFiles().front().c_str(), settings);
|
|
return nullptr;
|
|
}
|
|
|
|
bool CheckUnusedFunctions::analyseWholeProgram(const CTU::FileInfo *ctu, const std::list<Check::FileInfo*> &fileInfo, const Settings& settings, ErrorLogger &errorLogger)
|
|
{
|
|
(void)ctu;
|
|
(void)fileInfo;
|
|
return check(&errorLogger, settings);
|
|
}
|
|
|
|
CheckUnusedFunctions::FunctionDecl::FunctionDecl(const Function *f)
|
|
: functionName(f->name()), lineNumber(f->token->linenr())
|
|
{}
|
|
|
|
std::string CheckUnusedFunctions::analyzerInfo() const
|
|
{
|
|
std::ostringstream ret;
|
|
for (const FunctionDecl &functionDecl : mFunctionDecl) {
|
|
ret << " <functiondecl"
|
|
<< " functionName=\"" << ErrorLogger::toxml(functionDecl.functionName) << '\"'
|
|
<< " lineNumber=\"" << functionDecl.lineNumber << "\"/>\n";
|
|
}
|
|
for (const std::string &fc : mFunctionCalls) {
|
|
ret << " <functioncall functionName=\"" << ErrorLogger::toxml(fc) << "\"/>\n";
|
|
}
|
|
return ret.str();
|
|
}
|
|
|
|
namespace {
|
|
struct Location {
|
|
Location() : lineNumber(0) {}
|
|
Location(std::string f, const int l) : fileName(std::move(f)), lineNumber(l) {}
|
|
std::string fileName;
|
|
int lineNumber;
|
|
};
|
|
}
|
|
|
|
void CheckUnusedFunctions::analyseWholeProgram(const Settings &settings, ErrorLogger * const errorLogger, const std::string &buildDir)
|
|
{
|
|
std::map<std::string, Location> decls;
|
|
std::set<std::string> calls;
|
|
|
|
const std::string filesTxt(buildDir + "/files.txt");
|
|
std::ifstream fin(filesTxt.c_str());
|
|
std::string filesTxtLine;
|
|
while (std::getline(fin, filesTxtLine)) {
|
|
const std::string::size_type firstColon = filesTxtLine.find(':');
|
|
if (firstColon == std::string::npos)
|
|
continue;
|
|
const std::string::size_type secondColon = filesTxtLine.find(':', firstColon+1);
|
|
if (secondColon == std::string::npos)
|
|
continue;
|
|
const std::string xmlfile = buildDir + '/' + filesTxtLine.substr(0,firstColon);
|
|
const std::string sourcefile = filesTxtLine.substr(secondColon+1);
|
|
|
|
tinyxml2::XMLDocument doc;
|
|
const tinyxml2::XMLError error = doc.LoadFile(xmlfile.c_str());
|
|
if (error != tinyxml2::XML_SUCCESS)
|
|
continue;
|
|
|
|
const tinyxml2::XMLElement * const rootNode = doc.FirstChildElement();
|
|
if (rootNode == nullptr)
|
|
continue;
|
|
|
|
for (const tinyxml2::XMLElement *e = rootNode->FirstChildElement(); e; e = e->NextSiblingElement()) {
|
|
if (std::strcmp(e->Name(), "FileInfo") != 0)
|
|
continue;
|
|
const char *checkattr = e->Attribute("check");
|
|
if (checkattr == nullptr || std::strcmp(checkattr,"CheckUnusedFunctions") != 0)
|
|
continue;
|
|
for (const tinyxml2::XMLElement *e2 = e->FirstChildElement(); e2; e2 = e2->NextSiblingElement()) {
|
|
const char* functionName = e2->Attribute("functionName");
|
|
if (functionName == nullptr)
|
|
continue;
|
|
if (std::strcmp(e2->Name(),"functioncall") == 0) {
|
|
calls.insert(functionName);
|
|
continue;
|
|
} else if (std::strcmp(e2->Name(),"functiondecl") == 0) {
|
|
const char* lineNumber = e2->Attribute("lineNumber");
|
|
if (lineNumber)
|
|
decls[functionName] = Location(sourcefile, strToInt<int>(lineNumber));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
for (std::map<std::string, Location>::const_iterator decl = decls.cbegin(); decl != decls.cend(); ++decl) {
|
|
const std::string &functionName = decl->first;
|
|
|
|
if (settings.library.isentrypoint(functionName))
|
|
continue;
|
|
|
|
if (calls.find(functionName) == calls.end() && !isOperatorFunction(functionName)) {
|
|
const Location &loc = decl->second;
|
|
unusedFunctionError(errorLogger, loc.fileName, loc.lineNumber, functionName);
|
|
}
|
|
}
|
|
}
|