office-gobmx/compilerplugins/clang/literalalternative.cxx
Stephan Bergmann 1f078fcadd Prepare dual-mode compiler plugin feature
...which can act as either a rewriter or a non-rewriter that emits warnings.

Also added COMPILER_PLUGIN_WARNINGS_ONLY=X to demote warnings from plugin X from
errors to warnings, even under --enable-werror.

Change-Id: I05361936240a890515c6bba2459565417c1746b7
2014-01-27 13:12:33 +01:00

111 lines
4.4 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* 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/.
*/
#include <string>
#include "plugin.hxx"
// Find those calls of rtl::OUString::equalsIgnoreAsciiCaseAscii and
// rtl::OUString::equalsIgnoreAsciiCaseAsciiL that could be simplified to call
// rtl::OUString::equalsIgnoreAsciiCase instead:
namespace {
class LiteralAlternative:
public RecursiveASTVisitor<LiteralAlternative>, public loplugin::Plugin
{
public:
explicit LiteralAlternative(InstantiationData const & data): Plugin(data) {}
virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
bool VisitCallExpr(const CallExpr * expr);
};
bool LiteralAlternative::VisitCallExpr(const CallExpr * expr) {
if (ignoreLocation(expr)) {
return true;
}
FunctionDecl const * fdecl = expr->getDirectCallee();
if (fdecl == nullptr) {
return true;
}
std::string qname { fdecl->getQualifiedNameAsString() };
if (qname == "rtl::OUString::equalsIgnoreAsciiCaseAscii"
&& fdecl->getNumParams() == 1 && expr->getNumArgs() == 1)
{
// equalsIgnoreAsciiCaseAscii("foo") -> equalsIngoreAsciiCase("foo"):
StringLiteral const * lit
= dyn_cast<StringLiteral>(expr->getArg(0)->IgnoreParenImpCasts());
if (lit != nullptr) {
report(
DiagnosticsEngine::Warning,
("rewrite call of rtl::OUString::equalsIgnoreAsciiCaseAscii"
" with string literal argument as call of"
" rtl::OUString::equalsIgnoreAsciiCase"),
expr->getExprLoc());
//TODO: a better loc (the "equalsIgnoreAsciiCaseAscii" part)?
}
return true;
}
if (qname == "rtl::OUString::equalsIgnoreAsciiCaseAsciiL"
&& fdecl->getNumParams() == 2 && expr->getNumArgs() == 2)
{
// equalsIgnoreAsciiCaseAsciiL("foo", 3) -> equalsIngoreAsciiCase("foo")
// especially also for
// equalsIgnoreAsciiCaseAsciiL(RTL_CONSTASCII_STRINGPARAM("foo")), where
// RTL_CONSTASCII_STRINGPARAM expands to complicated expressions
// involving (&(X)[0] sub-expressions (and it might or might not be
// better to handle that at the level of non-expanded macros instead,
// but I have not found out how to do that yet anyway):
APSInt res;
if (expr->getArg(1)->isIntegerConstantExpr(res, compiler.getASTContext())) {
Expr const * arg0 = expr->getArg(0)->IgnoreParenImpCasts();
StringLiteral const * lit = dyn_cast<StringLiteral>(arg0);
bool match = false;
if (lit != nullptr) {
match = res == lit->getLength();
} else {
UnaryOperator const * op = dyn_cast<UnaryOperator>(arg0);
if (op != nullptr && op->getOpcode() == UO_AddrOf) {
ArraySubscriptExpr const * subs
= dyn_cast<ArraySubscriptExpr>(
op->getSubExpr()->IgnoreParenImpCasts());
if (subs != nullptr) {
lit = dyn_cast<StringLiteral>(
subs->getBase()->IgnoreParenImpCasts());
match = lit != nullptr
&& subs->getIdx()->isIntegerConstantExpr(
res, compiler.getASTContext())
&& res == 0;
}
}
}
if (match) {
report(
DiagnosticsEngine::Warning,
("rewrite call of"
" rtl::OUString::equalsIgnoreAsciiCaseAsciiL with string"
" literal and matching length arguments as call of"
" rtl::OUString::equalsIgnoreAsciiCase"),
expr->getExprLoc());
//TODO: a better loc (the "equalsIgnoreAsciiCaseAsciiL"
// part)?
}
}
return true;
}
return true;
}
loplugin::Plugin::Registration< LiteralAlternative > X("literalalternative");
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */