/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
// Find constant character array variables that are either
// (a) passed into O[U]String constructors
// (b) assigned to O[U]String
// and should thus be turned into O[U]StringLiteral variables.
//
// Such a variable may have been used in multiple places, not all of which would be compatible with
// changing the variable's type to O[U]StringLiteral. However, this plugin is aggressive and
// ignores all but the first use of such a variable. In all cases of incompatible uses so far, it
// was possible to change to surrounding code (for the better) to make the changes work.
//
// The plugin also flags O[U]StringLiteral variables of automatic storage duration, and uses of such
// variables with sizeof---two likely errors that can occur once a variable has been changed from a
// character array to O[U]StringLiteral.
//
//TODO: In theory, we should not only look for variables, but also for non-static data members. In
// practice, those should be rare, though, as they should arguably have been static data members to
// begin with.
#include <cassert>
#include "check.hxx"
#include "plugin.hxx"
namespace
{
bool isAutomaticVariable(VarDecl const* decl)
{
switch (cast<VarDecl>(decl)->getStorageDuration())
{
case SD_Automatic:
return true;
case SD_Thread:
case SD_Static:
return false;
case SD_FullExpression:
case SD_Dynamic:
assert(false);
default:
llvm_unreachable("unknown StorageDuration");
}
}
class StringLiteralVar final : public loplugin::FilteringPlugin<StringLiteralVar>
{
public:
explicit StringLiteralVar(loplugin::InstantiationData const& data)
: FilteringPlugin(data)
{
}
bool TraverseInitListExpr(InitListExpr* expr, DataRecursionQueue* queue = nullptr)
{
return WalkUpFromInitListExpr(expr)
&& TraverseSynOrSemInitListExpr(
expr->isSemanticForm() ? expr : expr->getSemanticForm(), queue);
}
bool VisitCXXConstructExpr(CXXConstructExpr const* expr)
{
if (ignoreLocation(expr))
{
return true;
}
loplugin::TypeCheck const tc(expr->getType());
if (!(tc.Class("OString").Namespace("rtl").GlobalNamespace()
|| tc.Class("OUString").Namespace("rtl").GlobalNamespace()))
{
return true;
}
auto const ctor = expr->getConstructor();
switch (ctor->getNumParams())
{
case 1:
{
auto const e = dyn_cast<DeclRefExpr>(expr->getArg(0)->IgnoreParenImpCasts());
if (e == nullptr)
{
return true;
}
auto const tc = loplugin::TypeCheck(e->getType());
if (!(tc.Class("OStringLiteral").Namespace("rtl").GlobalNamespace()
|| tc.Class("OUStringLiteral").Namespace("rtl").GlobalNamespace()))
{
return true;
}
auto const d = e->getDecl();
if (!isAutomaticVariable(cast<VarDecl>(d)))
{
return true;
}
if (!reportedAutomatic_.insert(d).second)
{
return true;
}
report(DiagnosticsEngine::Warning,
"variable %0 of type %1 with automatic storage duration most likely needs "
"to be static",
d->getLocation())
<< d << d->getType() << d->getSourceRange();
report(DiagnosticsEngine::Note, "first converted to %0 here", expr->getLocation())
<< expr->getType() << expr->getSourceRange();
}
break;
case 2:
{
auto const e1 = dyn_cast<DeclRefExpr>(expr->getArg(0)->IgnoreParenImpCasts());
if (e1 == nullptr)
{
return true;
}
auto const t = e1->getType();
if (!(t.isConstQualified() && t->isConstantArrayType()))
{
return true;
}
auto const e2 = expr->getArg(1);
if (!((isa<CXXDefaultArgExpr>(e2)
&& loplugin::TypeCheck(e2->getType())
.Struct("Dummy")
.Namespace("libreoffice_internal")
.Namespace("rtl")
.GlobalNamespace())
|| (loplugin::TypeCheck(ctor->getParamDecl(1)->getType())
.Typedef("sal_Int32")
.GlobalNamespace()
&& e2->isIntegerConstantExpr(compiler.getASTContext()))))
{
return true;
}
auto const d = e1->getDecl();
if (!reportedArray_.insert(d).second)
{
return true;
}
report(DiagnosticsEngine::Warning,
"change type of variable %0 from constant character array (%1) to "
"%select{OStringLiteral|OUStringLiteral}2%select{|, and make it static}3",
d->getLocation())
<< d << d->getType()
<< (tc.Class("OString").Namespace("rtl").GlobalNamespace() ? 0 : 1)
<< isAutomaticVariable(cast<VarDecl>(d)) << d->getSourceRange();
report(DiagnosticsEngine::Note, "first passed into a %0 constructor here",
expr->getLocation())
<< expr->getType().getUnqualifiedType() << expr->getSourceRange();
}
break;
}
return true;
}
bool VisitCXXOperatorCallExpr(CXXOperatorCallExpr const* expr)
{
if (ignoreLocation(expr))
{
return true;
}
if (expr->getOperator() != OO_Equal)
{
return true;
}
loplugin::TypeCheck const tc(expr->getType());
if (!(tc.Class("OString").Namespace("rtl").GlobalNamespace()
|| tc.Class("OUString").Namespace("rtl").GlobalNamespace()))
{
return true;
}
if (expr->getNumArgs() != 2)
{
return true;
}
auto const e = dyn_cast<DeclRefExpr>(expr->getArg(1)->IgnoreParenImpCasts());
if (e == nullptr)
{
return true;
}
auto const t = e->getType();
if (!(t.isConstQualified() && t->isConstantArrayType()))
{
return true;
}
auto const d = e->getDecl();
if (!reportedArray_.insert(d).second)
{
return true;
}
report(DiagnosticsEngine::Warning,
"change type of variable %0 from constant character array (%1) to "
"%select{OStringLiteral|OUStringLiteral}2%select{|, and make it static}3",
d->getLocation())
<< d << d->getType() << (tc.Class("OString").Namespace("rtl").GlobalNamespace() ? 0 : 1)
<< isAutomaticVariable(cast<VarDecl>(d)) << d->getSourceRange();
report(DiagnosticsEngine::Note, "first assigned here", compat::getBeginLoc(expr))
<< expr->getSourceRange();
return true;
}
bool VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr const* expr)
{
if (ignoreLocation(expr))
{
return true;
}
if (expr->getKind() != UETT_SizeOf)
{
return true;
}
if (expr->isArgumentType())
{
return true;
}
auto const e = dyn_cast<DeclRefExpr>(expr->getArgumentExpr()->IgnoreParenImpCasts());
if (e == nullptr)
{
return true;
}
auto const tc = loplugin::TypeCheck(e->getType());
if (!(tc.Class("OStringLiteral").Namespace("rtl").GlobalNamespace()
|| tc.Class("OUStringLiteral").Namespace("rtl").GlobalNamespace()))
{
return true;
}
auto const d = e->getDecl();
report(DiagnosticsEngine::Warning,
"variable %0 of type %1 suspiciously used in a sizeof expression", e->getLocation())
<< d << d->getType() << expr->getSourceRange();
return true;
}
bool preRun() override { return compiler.getLangOpts().CPlusPlus; }
private:
void run() override
{
if (preRun())
{
TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
}
}
std::set<Decl const*> reportedAutomatic_;
std::set<Decl const*> reportedArray_;
};
static loplugin::Plugin::Registration<StringLiteralVar> reg("stringliteralvar");
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */