compilerplugins/clang/xmlimport.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * Based on LLVM/Clang.
   6  *
   7  * This file is distributed under the University of Illinois Open Source
   8  * License. See LICENSE.TXT for details.
   9  *
  10  */
  11 #ifndef LO_CLANG_SHARED_PLUGINS
  12
  13 #include "plugin.hxx"
  14 #include "check.hxx"
  15 #include "config_clang.h"
  16 #include <iostream>
  17 #include <unordered_map>
  18 #include "clang/AST/CXXInheritance.h"
  19
  20 /*
  21  * This is a compile-time checker.
  22  *
  23  * Check that when we override SvXmlImportContext, and we override createFastChildContext,
  24  * we have also overridden startFastElement, or the fast-parser stuff will not work
  25  * correctly.
  26 */
  27
  28 namespace
  29 {
  30 class XmlImport : public loplugin::FilteringPlugin<XmlImport>
  31 {
  32 public:
  33     explicit XmlImport(loplugin::InstantiationData const& data)
  34         : FilteringPlugin(data)
  35     {
  36     }
  37
  38     bool preRun() override
  39     {
  40         StringRef fn(handler.getMainFileName());
  41         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/core/xmlictxt.cxx"))
  42             return false;
  43         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/core/xmlimp.cxx"))
  44             return false;
  45         // These are mostly classes delegating calls to other classes
  46         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/text/XMLTextFrameContext.cxx"))
  47             return false;
  48         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/draw/ximpshap.cxx"))
  49             return false;
  50         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/table/XMLTableImport.cxx"))
  51             return false;
  52         if (loplugin::isSamePathname(fn,
  53                                      SRCDIR "/sc/source/filter/xml/XMLTrackedChangesContext.cxx"))
  54             return false;
  55         if (loplugin::isSamePathname(fn, SRCDIR "/sc/source/filter/xml/xmlannoi.cxx"))
  56             return false;
  57         // this class specifically wants to prevent some endFastElement processing happening in its superclass
  58         if (loplugin::isSamePathname(fn, SRCDIR
  59                                      "/xmloff/source/text/XMLIndexBibliographySourceContext.cxx"))
  60             return false;
  61         // calling mxSlaveContext
  62         if (loplugin::isSamePathname(fn, SRCDIR "/xmloff/source/draw/XMLNumberStyles.cxx"))
  63             return false;
  64         return true;
  65     }
  66
  67     void run() override
  68     {
  69         if (preRun())
  70         {
  71             TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  72         }
  73     }
  74
  75     bool VisitCXXMethodDecl(const CXXMethodDecl*);
  76     bool VisitCXXMemberCallExpr(const CXXMemberCallExpr*);
  77     bool VisitBinaryOperator(const BinaryOperator*);
  78     bool VisitSwitchStmt(const SwitchStmt*);
  79     bool VisitCallExpr(const CallExpr*);
  80
  81 private:
  82     bool isXmlTokEnum(const Expr*);
  83     bool isUInt16(const Expr*);
  84     bool isUInt16(QualType);
  85
  86     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> startFastElementSet;
  87     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> StartElementSet;
  88     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> endFastElementSet;
  89     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> EndElementSet;
  90     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> charactersSet;
  91     std::unordered_map<const CXXRecordDecl*, const CXXMethodDecl*> CharactersSet;
  92 };
  93
  94 bool XmlImport::VisitCXXMethodDecl(const CXXMethodDecl* methodDecl)
  95 {
  96     auto beginLoc = methodDecl->getBeginLoc();
  97     if (!beginLoc.isValid() || ignoreLocation(beginLoc))
  98         return true;
  99
 100     if (!methodDecl->getIdentifier())
 101         return true;
 102
 103     auto cxxRecordDecl = methodDecl->getParent();
 104     if (!cxxRecordDecl || !cxxRecordDecl->getIdentifier())
 105         return true;
 106
 107     if (loplugin::DeclCheck(cxxRecordDecl).Class("SvXMLImportContext"))
 108         return true;
 109
 110     if (!loplugin::isDerivedFrom(cxxRecordDecl, [](Decl const* decl) -> bool {
 111             auto const dc = loplugin::DeclCheck(decl);
 112             return bool(dc.ClassOrStruct("SvXMLImportContext").GlobalNamespace());
 113         }))
 114         return true;
 115
 116     auto name = methodDecl->getName();
 117     if (name == "startFastElement")
 118         startFastElementSet.insert({ cxxRecordDecl, methodDecl });
 119     else if (name == "StartElement")
 120         StartElementSet.insert({ cxxRecordDecl, methodDecl });
 121     else if (name == "endFastElement")
 122         endFastElementSet.insert({ cxxRecordDecl, methodDecl });
 123     else if (name == "EndElement")
 124         EndElementSet.insert({ cxxRecordDecl, methodDecl });
 125     else if (name == "characters")
 126     {
 127         if (methodDecl->getNumParams() == 1)
 128             charactersSet.insert({ cxxRecordDecl, methodDecl });
 129     }
 130     else if (name == "Characters")
 131     {
 132         if (methodDecl->getNumParams() == 1)
 133             CharactersSet.insert({ cxxRecordDecl, methodDecl });
 134     }
 135
 136     {
 137         auto it1 = endFastElementSet.find(cxxRecordDecl);
 138         auto it2 = EndElementSet.find(cxxRecordDecl);
 139         if (it1 != endFastElementSet.end() && it2 != EndElementSet.end())
 140         {
 141             auto methodDecl1 = it1->second;
 142             report(DiagnosticsEngine::Warning, "cannot override both endFastElement and EndElement",
 143                    methodDecl1->getBeginLoc())
 144                 << methodDecl1->getSourceRange();
 145             auto methodDecl2 = it2->second;
 146             report(DiagnosticsEngine::Warning, "cannot override both endFastElement and EndElement",
 147                    methodDecl2->getBeginLoc())
 148                 << methodDecl2->getSourceRange();
 149         }
 150     }
 151
 152     {
 153         auto it1 = startFastElementSet.find(cxxRecordDecl);
 154         auto it2 = StartElementSet.find(cxxRecordDecl);
 155         if (it1 != startFastElementSet.end() && it2 != StartElementSet.end())
 156         {
 157             auto methodDecl1 = it1->second;
 158             report(DiagnosticsEngine::Warning,
 159                    "cannot override both startFastElement and StartElement",
 160                    methodDecl1->getBeginLoc())
 161                 << methodDecl1->getSourceRange();
 162             auto methodDecl2 = it2->second;
 163             report(DiagnosticsEngine::Warning,
 164                    "cannot override both startFastElement and StartElement",
 165                    methodDecl2->getBeginLoc())
 166                 << methodDecl2->getSourceRange();
 167         }
 168     }
 169     {
 170         auto it1 = charactersSet.find(cxxRecordDecl);
 171         auto it2 = CharactersSet.find(cxxRecordDecl);
 172         if (it1 != charactersSet.end() && it2 != CharactersSet.end())
 173         {
 174             auto methodDecl1 = it1->second;
 175             report(DiagnosticsEngine::Warning, "cannot override both characters and Characters",
 176                    methodDecl1->getBeginLoc())
 177                 << methodDecl1->getSourceRange();
 178             auto methodDecl2 = it2->second;
 179             report(DiagnosticsEngine::Warning, "cannot override both characters and Characters",
 180                    methodDecl2->getBeginLoc())
 181                 << methodDecl2->getSourceRange();
 182         }
 183     }
 184
 185     auto checkEmpty = [&]() {
 186         if (!methodDecl->isThisDeclarationADefinition())
 187             return;
 188         auto compoundStmt = dyn_cast_or_null<CompoundStmt>(methodDecl->getBody());
 189         if (compoundStmt == nullptr || compoundStmt->size() > 0)
 190             return;
 191         report(DiagnosticsEngine::Warning, "empty, should be removed", methodDecl->getBeginLoc())
 192             << methodDecl->getSourceRange();
 193         auto canonicalDecl = methodDecl->getCanonicalDecl();
 194         if (canonicalDecl != methodDecl)
 195             report(DiagnosticsEngine::Note, "definition here", canonicalDecl->getBeginLoc())
 196                 << canonicalDecl->getSourceRange();
 197     };
 198     auto checkOnlyReturn = [&]() {
 199         if (!methodDecl->isThisDeclarationADefinition())
 200             return;
 201         auto compoundStmt = dyn_cast_or_null<CompoundStmt>(methodDecl->getBody());
 202         if (compoundStmt == nullptr || compoundStmt->size() > 1)
 203             return;
 204         auto returnStmt = dyn_cast_or_null<ReturnStmt>(*compoundStmt->body_begin());
 205         if (!returnStmt)
 206             return;
 207         auto cxxConstructExpr
 208             = dyn_cast_or_null<CXXConstructExpr>(returnStmt->getRetValue()->IgnoreImplicit());
 209         if (!cxxConstructExpr)
 210             return;
 211         if (cxxConstructExpr->getNumArgs() != 1)
 212             return;
 213         if (!isa<CXXNullPtrLiteralExpr>(cxxConstructExpr->getArg(0)->IgnoreImplicit()))
 214             return;
 215         report(DiagnosticsEngine::Warning, "empty, should be removed", methodDecl->getBeginLoc())
 216             << methodDecl->getSourceRange();
 217         auto canonicalDecl = methodDecl->getCanonicalDecl();
 218         if (canonicalDecl != methodDecl)
 219             report(DiagnosticsEngine::Note, "definition here", canonicalDecl->getBeginLoc())
 220                 << canonicalDecl->getSourceRange();
 221     };
 222
 223     if (name == "startFastElement")
 224         checkEmpty();
 225     else if (name == "endFastElement")
 226         checkEmpty();
 227     else if (name == "characters")
 228         checkEmpty();
 229     else if (name == "createFastChildContext")
 230         checkOnlyReturn();
 231     else if (name == "createUnknownChildContext")
 232         checkOnlyReturn();
 233
 234     return true;
 235 }
 236
 237 bool XmlImport::VisitCXXMemberCallExpr(const CXXMemberCallExpr* callExpr)
 238 {
 239     auto beginLoc = callExpr->getBeginLoc();
 240     if (!beginLoc.isValid() || ignoreLocation(callExpr))
 241         return true;
 242
 243     CXXMethodDecl* methodDecl = callExpr->getMethodDecl();
 244     if (!methodDecl || !methodDecl->getIdentifier())
 245         return true;
 246
 247     auto cxxRecordDecl = methodDecl->getParent();
 248     if (!cxxRecordDecl || !cxxRecordDecl->getIdentifier())
 249         return true;
 250
 251     if (!loplugin::DeclCheck(cxxRecordDecl).Class("SvXMLImportContext"))
 252         return true;
 253
 254     auto name = methodDecl->getName();
 255     if (name == "startFastElement" || name == "characters" || name == "endFastElement"
 256         || name == "createFastChildContext" || name == "createUnknownChildContext"
 257         || name == "StartElement" || name == "EndElement" || name == "Characters"
 258         || name == "CreateChildContext")
 259     {
 260         /**
 261          * Calling this superclass method from a subclass method will mess with the fallback logic in the superclass.
 262          */
 263         report(DiagnosticsEngine::Warning, "don't call this superclass method",
 264                callExpr->getBeginLoc())
 265             << callExpr->getSourceRange();
 266     }
 267     return true;
 268 }
 269
 270 bool XmlImport::VisitBinaryOperator(const BinaryOperator* binaryOp)
 271 {
 272     auto beginLoc = binaryOp->getBeginLoc();
 273     if (!beginLoc.isValid() || ignoreLocation(binaryOp))
 274         return true;
 275     auto op = binaryOp->getOpcode();
 276     if (op != BO_EQ && op != BO_NE)
 277         return true;
 278     auto check2 = [&](const Expr* expr) -> void {
 279         if (!isUInt16(expr))
 280             report(DiagnosticsEngine::Warning,
 281                    "comparing XML_TOK enum to 'sal_uInt32', expected sal_uInt16",
 282                    binaryOp->getBeginLoc())
 283                 << binaryOp->getSourceRange();
 284     };
 285     if (isXmlTokEnum(binaryOp->getLHS()))
 286         check2(binaryOp->getRHS());
 287     else if (isXmlTokEnum(binaryOp->getRHS()))
 288         check2(binaryOp->getLHS());
 289     return true;
 290 }
 291
 292 bool XmlImport::VisitSwitchStmt(const SwitchStmt* switchStmt)
 293 {
 294     auto beginLoc = switchStmt->getBeginLoc();
 295     if (!beginLoc.isValid() || ignoreLocation(switchStmt))
 296         return true;
 297     if (isUInt16(switchStmt->getCond()))
 298         return true;
 299     // if the condition is an enum type, ignore this switch
 300     auto condEnumType = switchStmt->getCond()
 301                             ->IgnoreImplicit()
 302                             ->getType()
 303                             ->getUnqualifiedDesugaredType()
 304                             ->getAs<EnumType>();
 305     if (condEnumType)
 306         return true;
 307     auto switchCaseStmt = switchStmt->getSwitchCaseList();
 308     for (; switchCaseStmt != nullptr; switchCaseStmt = switchCaseStmt->getNextSwitchCase())
 309     {
 310         auto caseStmt = dyn_cast<CaseStmt>(switchCaseStmt);
 311         if (!caseStmt)
 312             continue;
 313         if (!isXmlTokEnum(caseStmt->getLHS()))
 314             continue;
 315         report(DiagnosticsEngine::Warning,
 316                "comparing XML_TOK enum to 'sal_uInt32', expected sal_uInt16",
 317                caseStmt->getBeginLoc())
 318             << caseStmt->getSourceRange();
 319     }
 320     return true;
 321 }
 322
 323 bool XmlImport::VisitCallExpr(const CallExpr* callExpr)
 324 {
 325     auto beginLoc = callExpr->getBeginLoc();
 326     if (!beginLoc.isValid() || ignoreLocation(callExpr))
 327         return true;
 328
 329     const FunctionDecl* functionDecl;
 330     if (isa<CXXMemberCallExpr>(callExpr))
 331         functionDecl = dyn_cast<CXXMemberCallExpr>(callExpr)->getMethodDecl();
 332     else
 333         functionDecl = callExpr->getDirectCallee();
 334     if (!functionDecl)
 335         return true;
 336     for (unsigned i = 0; i != callExpr->getNumArgs(); ++i)
 337     {
 338         auto argExpr = callExpr->getArg(i)->IgnoreImplicit();
 339         if (!isXmlTokEnum(argExpr))
 340             continue;
 341         // if the condition is an enum type, ignore this switch
 342         auto condEnumType = functionDecl->getParamDecl(i)
 343                                 ->getType()
 344                                 ->getUnqualifiedDesugaredType()
 345                                 ->getAs<EnumType>();
 346         if (condEnumType)
 347             continue;
 348         if (isUInt16(functionDecl->getParamDecl(i)->getType()))
 349             return true;
 350         report(DiagnosticsEngine::Warning,
 351                "passing XML_TOK enum to 'sal_Int32', wrong param or XML token type",
 352                callExpr->getBeginLoc())
 353             << callExpr->getSourceRange();
 354     }
 355
 356     return true;
 357 }
 358
 359 bool XmlImport::isXmlTokEnum(const Expr* expr)
 360 {
 361     expr = expr->IgnoreImplicit();
 362     // check that we have an unscoped enum type
 363     auto condEnumType = expr->getType()->getUnqualifiedDesugaredType()->getAs<EnumType>();
 364     if (!condEnumType || condEnumType->getDecl()->isScoped())
 365         return false;
 366     auto declRefExpr = dyn_cast<DeclRefExpr>(expr);
 367     if (!declRefExpr)
 368         return false;
 369     auto enumConstant = dyn_cast<EnumConstantDecl>(declRefExpr->getDecl());
 370     if (!enumConstant)
 371         return false;
 372     return enumConstant->getIdentifier() && enumConstant->getName().startswith("XML_TOK_");
 373 }
 374
 375 bool XmlImport::isUInt16(const Expr* expr)
 376 {
 377     expr = expr->IgnoreImplicit();
 378     return isUInt16(expr->getType());
 379 }
 380
 381 bool XmlImport::isUInt16(QualType qt)
 382 {
 383     if (qt->isSpecificBuiltinType(BuiltinType::UShort))
 384         return true;
 385     return bool(loplugin::TypeCheck(qt).Typedef("sal_uInt16"));
 386 }
 387
 388 loplugin::Plugin::Registration<XmlImport> xmlimport("xmlimport");
 389
 390 } // namespace
 391
 392 #endif // LO_CLANG_SHARED_PLUGINS
 393
 394 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */