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      1 //===- CIndexCodeCompletion.cpp - Code Completion API hooks ---------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file implements the Clang-C Source Indexing library hooks for
     11 // code completion.
     12 //
     13 //===----------------------------------------------------------------------===//
     14 
     15 #include "CIndexer.h"
     16 #include "CXTranslationUnit.h"
     17 #include "CXString.h"
     18 #include "CXCursor.h"
     19 #include "CXString.h"
     20 #include "CIndexDiagnostic.h"
     21 #include "clang/AST/Type.h"
     22 #include "clang/AST/Decl.h"
     23 #include "clang/AST/DeclObjC.h"
     24 #include "clang/Basic/SourceManager.h"
     25 #include "clang/Basic/FileManager.h"
     26 #include "clang/Frontend/ASTUnit.h"
     27 #include "clang/Frontend/CompilerInstance.h"
     28 #include "clang/Frontend/FrontendDiagnostic.h"
     29 #include "clang/Sema/CodeCompleteConsumer.h"
     30 #include "llvm/ADT/SmallString.h"
     31 #include "llvm/ADT/StringExtras.h"
     32 #include "llvm/Support/Atomic.h"
     33 #include "llvm/Support/CrashRecoveryContext.h"
     34 #include "llvm/Support/MemoryBuffer.h"
     35 #include "llvm/Support/Timer.h"
     36 #include "llvm/Support/raw_ostream.h"
     37 #include "llvm/Support/Program.h"
     38 #include <cstdlib>
     39 #include <cstdio>
     40 
     41 
     42 #ifdef UDP_CODE_COMPLETION_LOGGER
     43 #include "clang/Basic/Version.h"
     44 #include <arpa/inet.h>
     45 #include <sys/socket.h>
     46 #include <sys/types.h>
     47 #include <unistd.h>
     48 #endif
     49 
     50 using namespace clang;
     51 using namespace clang::cxstring;
     52 
     53 extern "C" {
     54 
     55 enum CXCompletionChunkKind
     56 clang_getCompletionChunkKind(CXCompletionString completion_string,
     57                              unsigned chunk_number) {
     58   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
     59   if (!CCStr || chunk_number >= CCStr->size())
     60     return CXCompletionChunk_Text;
     61 
     62   switch ((*CCStr)[chunk_number].Kind) {
     63   case CodeCompletionString::CK_TypedText:
     64     return CXCompletionChunk_TypedText;
     65   case CodeCompletionString::CK_Text:
     66     return CXCompletionChunk_Text;
     67   case CodeCompletionString::CK_Optional:
     68     return CXCompletionChunk_Optional;
     69   case CodeCompletionString::CK_Placeholder:
     70     return CXCompletionChunk_Placeholder;
     71   case CodeCompletionString::CK_Informative:
     72     return CXCompletionChunk_Informative;
     73   case CodeCompletionString::CK_ResultType:
     74     return CXCompletionChunk_ResultType;
     75   case CodeCompletionString::CK_CurrentParameter:
     76     return CXCompletionChunk_CurrentParameter;
     77   case CodeCompletionString::CK_LeftParen:
     78     return CXCompletionChunk_LeftParen;
     79   case CodeCompletionString::CK_RightParen:
     80     return CXCompletionChunk_RightParen;
     81   case CodeCompletionString::CK_LeftBracket:
     82     return CXCompletionChunk_LeftBracket;
     83   case CodeCompletionString::CK_RightBracket:
     84     return CXCompletionChunk_RightBracket;
     85   case CodeCompletionString::CK_LeftBrace:
     86     return CXCompletionChunk_LeftBrace;
     87   case CodeCompletionString::CK_RightBrace:
     88     return CXCompletionChunk_RightBrace;
     89   case CodeCompletionString::CK_LeftAngle:
     90     return CXCompletionChunk_LeftAngle;
     91   case CodeCompletionString::CK_RightAngle:
     92     return CXCompletionChunk_RightAngle;
     93   case CodeCompletionString::CK_Comma:
     94     return CXCompletionChunk_Comma;
     95   case CodeCompletionString::CK_Colon:
     96     return CXCompletionChunk_Colon;
     97   case CodeCompletionString::CK_SemiColon:
     98     return CXCompletionChunk_SemiColon;
     99   case CodeCompletionString::CK_Equal:
    100     return CXCompletionChunk_Equal;
    101   case CodeCompletionString::CK_HorizontalSpace:
    102     return CXCompletionChunk_HorizontalSpace;
    103   case CodeCompletionString::CK_VerticalSpace:
    104     return CXCompletionChunk_VerticalSpace;
    105   }
    106 
    107   // Should be unreachable, but let's be careful.
    108   return CXCompletionChunk_Text;
    109 }
    110 
    111 CXString clang_getCompletionChunkText(CXCompletionString completion_string,
    112                                       unsigned chunk_number) {
    113   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    114   if (!CCStr || chunk_number >= CCStr->size())
    115     return createCXString((const char*)0);
    116 
    117   switch ((*CCStr)[chunk_number].Kind) {
    118   case CodeCompletionString::CK_TypedText:
    119   case CodeCompletionString::CK_Text:
    120   case CodeCompletionString::CK_Placeholder:
    121   case CodeCompletionString::CK_CurrentParameter:
    122   case CodeCompletionString::CK_Informative:
    123   case CodeCompletionString::CK_LeftParen:
    124   case CodeCompletionString::CK_RightParen:
    125   case CodeCompletionString::CK_LeftBracket:
    126   case CodeCompletionString::CK_RightBracket:
    127   case CodeCompletionString::CK_LeftBrace:
    128   case CodeCompletionString::CK_RightBrace:
    129   case CodeCompletionString::CK_LeftAngle:
    130   case CodeCompletionString::CK_RightAngle:
    131   case CodeCompletionString::CK_Comma:
    132   case CodeCompletionString::CK_ResultType:
    133   case CodeCompletionString::CK_Colon:
    134   case CodeCompletionString::CK_SemiColon:
    135   case CodeCompletionString::CK_Equal:
    136   case CodeCompletionString::CK_HorizontalSpace:
    137   case CodeCompletionString::CK_VerticalSpace:
    138     return createCXString((*CCStr)[chunk_number].Text, false);
    139 
    140   case CodeCompletionString::CK_Optional:
    141     // Note: treated as an empty text block.
    142     return createCXString("");
    143   }
    144 
    145   // Should be unreachable, but let's be careful.
    146   return createCXString((const char*)0);
    147 }
    148 
    149 
    150 CXCompletionString
    151 clang_getCompletionChunkCompletionString(CXCompletionString completion_string,
    152                                          unsigned chunk_number) {
    153   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    154   if (!CCStr || chunk_number >= CCStr->size())
    155     return 0;
    156 
    157   switch ((*CCStr)[chunk_number].Kind) {
    158   case CodeCompletionString::CK_TypedText:
    159   case CodeCompletionString::CK_Text:
    160   case CodeCompletionString::CK_Placeholder:
    161   case CodeCompletionString::CK_CurrentParameter:
    162   case CodeCompletionString::CK_Informative:
    163   case CodeCompletionString::CK_LeftParen:
    164   case CodeCompletionString::CK_RightParen:
    165   case CodeCompletionString::CK_LeftBracket:
    166   case CodeCompletionString::CK_RightBracket:
    167   case CodeCompletionString::CK_LeftBrace:
    168   case CodeCompletionString::CK_RightBrace:
    169   case CodeCompletionString::CK_LeftAngle:
    170   case CodeCompletionString::CK_RightAngle:
    171   case CodeCompletionString::CK_Comma:
    172   case CodeCompletionString::CK_ResultType:
    173   case CodeCompletionString::CK_Colon:
    174   case CodeCompletionString::CK_SemiColon:
    175   case CodeCompletionString::CK_Equal:
    176   case CodeCompletionString::CK_HorizontalSpace:
    177   case CodeCompletionString::CK_VerticalSpace:
    178     return 0;
    179 
    180   case CodeCompletionString::CK_Optional:
    181     // Note: treated as an empty text block.
    182     return (*CCStr)[chunk_number].Optional;
    183   }
    184 
    185   // Should be unreachable, but let's be careful.
    186   return 0;
    187 }
    188 
    189 unsigned clang_getNumCompletionChunks(CXCompletionString completion_string) {
    190   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    191   return CCStr? CCStr->size() : 0;
    192 }
    193 
    194 unsigned clang_getCompletionPriority(CXCompletionString completion_string) {
    195   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    196   return CCStr? CCStr->getPriority() : unsigned(CCP_Unlikely);
    197 }
    198 
    199 enum CXAvailabilityKind
    200 clang_getCompletionAvailability(CXCompletionString completion_string) {
    201   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    202   return CCStr? static_cast<CXAvailabilityKind>(CCStr->getAvailability())
    203               : CXAvailability_Available;
    204 }
    205 
    206 unsigned clang_getCompletionNumAnnotations(CXCompletionString completion_string)
    207 {
    208   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    209   return CCStr ? CCStr->getAnnotationCount() : 0;
    210 }
    211 
    212 CXString clang_getCompletionAnnotation(CXCompletionString completion_string,
    213                                        unsigned annotation_number) {
    214   CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
    215   return CCStr ? createCXString(CCStr->getAnnotation(annotation_number))
    216                : createCXString((const char *) 0);
    217 }
    218 
    219 
    220 /// \brief The CXCodeCompleteResults structure we allocate internally;
    221 /// the client only sees the initial CXCodeCompleteResults structure.
    222 struct AllocatedCXCodeCompleteResults : public CXCodeCompleteResults {
    223   AllocatedCXCodeCompleteResults(const FileSystemOptions& FileSystemOpts);
    224   ~AllocatedCXCodeCompleteResults();
    225 
    226   /// \brief Diagnostics produced while performing code completion.
    227   SmallVector<StoredDiagnostic, 8> Diagnostics;
    228 
    229   /// \brief Diag object
    230   llvm::IntrusiveRefCntPtr<DiagnosticsEngine> Diag;
    231 
    232   /// \brief Language options used to adjust source locations.
    233   LangOptions LangOpts;
    234 
    235   FileSystemOptions FileSystemOpts;
    236 
    237   /// \brief File manager, used for diagnostics.
    238   llvm::IntrusiveRefCntPtr<FileManager> FileMgr;
    239 
    240   /// \brief Source manager, used for diagnostics.
    241   llvm::IntrusiveRefCntPtr<SourceManager> SourceMgr;
    242 
    243   /// \brief Temporary files that should be removed once we have finished
    244   /// with the code-completion results.
    245   std::vector<llvm::sys::Path> TemporaryFiles;
    246 
    247   /// \brief Temporary buffers that will be deleted once we have finished with
    248   /// the code-completion results.
    249   SmallVector<const llvm::MemoryBuffer *, 1> TemporaryBuffers;
    250 
    251   /// \brief Allocator used to store globally cached code-completion results.
    252   llvm::IntrusiveRefCntPtr<clang::GlobalCodeCompletionAllocator>
    253     CachedCompletionAllocator;
    254 
    255   /// \brief Allocator used to store code completion results.
    256   clang::CodeCompletionAllocator CodeCompletionAllocator;
    257 
    258   /// \brief Context under which completion occurred.
    259   enum clang::CodeCompletionContext::Kind ContextKind;
    260 
    261   /// \brief A bitfield representing the acceptable completions for the
    262   /// current context.
    263   unsigned long long Contexts;
    264 
    265   /// \brief The kind of the container for the current context for completions.
    266   enum CXCursorKind ContainerKind;
    267   /// \brief The USR of the container for the current context for completions.
    268   CXString ContainerUSR;
    269   /// \brief a boolean value indicating whether there is complete information
    270   /// about the container
    271   unsigned ContainerIsIncomplete;
    272 
    273   /// \brief A string containing the Objective-C selector entered thus far for a
    274   /// message send.
    275   std::string Selector;
    276 };
    277 
    278 /// \brief Tracks the number of code-completion result objects that are
    279 /// currently active.
    280 ///
    281 /// Used for debugging purposes only.
    282 static llvm::sys::cas_flag CodeCompletionResultObjects;
    283 
    284 AllocatedCXCodeCompleteResults::AllocatedCXCodeCompleteResults(
    285                                       const FileSystemOptions& FileSystemOpts)
    286   : CXCodeCompleteResults(),
    287     Diag(new DiagnosticsEngine(
    288                    llvm::IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs))),
    289     FileSystemOpts(FileSystemOpts),
    290     FileMgr(new FileManager(FileSystemOpts)),
    291     SourceMgr(new SourceManager(*Diag, *FileMgr)),
    292     Contexts(CXCompletionContext_Unknown),
    293     ContainerKind(CXCursor_InvalidCode),
    294     ContainerUSR(createCXString("")),
    295     ContainerIsIncomplete(1)
    296 {
    297   if (getenv("LIBCLANG_OBJTRACKING")) {
    298     llvm::sys::AtomicIncrement(&CodeCompletionResultObjects);
    299     fprintf(stderr, "+++ %d completion results\n", CodeCompletionResultObjects);
    300   }
    301 }
    302 
    303 AllocatedCXCodeCompleteResults::~AllocatedCXCodeCompleteResults() {
    304   delete [] Results;
    305 
    306   clang_disposeString(ContainerUSR);
    307 
    308   for (unsigned I = 0, N = TemporaryFiles.size(); I != N; ++I)
    309     TemporaryFiles[I].eraseFromDisk();
    310   for (unsigned I = 0, N = TemporaryBuffers.size(); I != N; ++I)
    311     delete TemporaryBuffers[I];
    312 
    313   if (getenv("LIBCLANG_OBJTRACKING")) {
    314     llvm::sys::AtomicDecrement(&CodeCompletionResultObjects);
    315     fprintf(stderr, "--- %d completion results\n", CodeCompletionResultObjects);
    316   }
    317 }
    318 
    319 } // end extern "C"
    320 
    321 static unsigned long long getContextsForContextKind(
    322                                           enum CodeCompletionContext::Kind kind,
    323                                                     Sema &S) {
    324   unsigned long long contexts = 0;
    325   switch (kind) {
    326     case CodeCompletionContext::CCC_OtherWithMacros: {
    327       //We can allow macros here, but we don't know what else is permissible
    328       //So we'll say the only thing permissible are macros
    329       contexts = CXCompletionContext_MacroName;
    330       break;
    331     }
    332     case CodeCompletionContext::CCC_TopLevel:
    333     case CodeCompletionContext::CCC_ObjCIvarList:
    334     case CodeCompletionContext::CCC_ClassStructUnion:
    335     case CodeCompletionContext::CCC_Type: {
    336       contexts = CXCompletionContext_AnyType |
    337                  CXCompletionContext_ObjCInterface;
    338       if (S.getLangOptions().CPlusPlus) {
    339         contexts |= CXCompletionContext_EnumTag |
    340                     CXCompletionContext_UnionTag |
    341                     CXCompletionContext_StructTag |
    342                     CXCompletionContext_ClassTag |
    343                     CXCompletionContext_NestedNameSpecifier;
    344       }
    345       break;
    346     }
    347     case CodeCompletionContext::CCC_Statement: {
    348       contexts = CXCompletionContext_AnyType |
    349                  CXCompletionContext_ObjCInterface |
    350                  CXCompletionContext_AnyValue;
    351       if (S.getLangOptions().CPlusPlus) {
    352         contexts |= CXCompletionContext_EnumTag |
    353                     CXCompletionContext_UnionTag |
    354                     CXCompletionContext_StructTag |
    355                     CXCompletionContext_ClassTag |
    356                     CXCompletionContext_NestedNameSpecifier;
    357       }
    358       break;
    359     }
    360     case CodeCompletionContext::CCC_Expression: {
    361       contexts = CXCompletionContext_AnyValue;
    362       if (S.getLangOptions().CPlusPlus) {
    363         contexts |= CXCompletionContext_AnyType |
    364                     CXCompletionContext_ObjCInterface |
    365                     CXCompletionContext_EnumTag |
    366                     CXCompletionContext_UnionTag |
    367                     CXCompletionContext_StructTag |
    368                     CXCompletionContext_ClassTag |
    369                     CXCompletionContext_NestedNameSpecifier;
    370       }
    371       break;
    372     }
    373     case CodeCompletionContext::CCC_ObjCMessageReceiver: {
    374       contexts = CXCompletionContext_ObjCObjectValue |
    375                  CXCompletionContext_ObjCSelectorValue |
    376                  CXCompletionContext_ObjCInterface;
    377       if (S.getLangOptions().CPlusPlus) {
    378         contexts |= CXCompletionContext_CXXClassTypeValue |
    379                     CXCompletionContext_AnyType |
    380                     CXCompletionContext_EnumTag |
    381                     CXCompletionContext_UnionTag |
    382                     CXCompletionContext_StructTag |
    383                     CXCompletionContext_ClassTag |
    384                     CXCompletionContext_NestedNameSpecifier;
    385       }
    386       break;
    387     }
    388     case CodeCompletionContext::CCC_DotMemberAccess: {
    389       contexts = CXCompletionContext_DotMemberAccess;
    390       break;
    391     }
    392     case CodeCompletionContext::CCC_ArrowMemberAccess: {
    393       contexts = CXCompletionContext_ArrowMemberAccess;
    394       break;
    395     }
    396     case CodeCompletionContext::CCC_ObjCPropertyAccess: {
    397       contexts = CXCompletionContext_ObjCPropertyAccess;
    398       break;
    399     }
    400     case CodeCompletionContext::CCC_EnumTag: {
    401       contexts = CXCompletionContext_EnumTag |
    402                  CXCompletionContext_NestedNameSpecifier;
    403       break;
    404     }
    405     case CodeCompletionContext::CCC_UnionTag: {
    406       contexts = CXCompletionContext_UnionTag |
    407                  CXCompletionContext_NestedNameSpecifier;
    408       break;
    409     }
    410     case CodeCompletionContext::CCC_ClassOrStructTag: {
    411       contexts = CXCompletionContext_StructTag |
    412                  CXCompletionContext_ClassTag |
    413                  CXCompletionContext_NestedNameSpecifier;
    414       break;
    415     }
    416     case CodeCompletionContext::CCC_ObjCProtocolName: {
    417       contexts = CXCompletionContext_ObjCProtocol;
    418       break;
    419     }
    420     case CodeCompletionContext::CCC_Namespace: {
    421       contexts = CXCompletionContext_Namespace;
    422       break;
    423     }
    424     case CodeCompletionContext::CCC_PotentiallyQualifiedName: {
    425       contexts = CXCompletionContext_NestedNameSpecifier;
    426       break;
    427     }
    428     case CodeCompletionContext::CCC_MacroNameUse: {
    429       contexts = CXCompletionContext_MacroName;
    430       break;
    431     }
    432     case CodeCompletionContext::CCC_NaturalLanguage: {
    433       contexts = CXCompletionContext_NaturalLanguage;
    434       break;
    435     }
    436     case CodeCompletionContext::CCC_SelectorName: {
    437       contexts = CXCompletionContext_ObjCSelectorName;
    438       break;
    439     }
    440     case CodeCompletionContext::CCC_ParenthesizedExpression: {
    441       contexts = CXCompletionContext_AnyType |
    442                  CXCompletionContext_ObjCInterface |
    443                  CXCompletionContext_AnyValue;
    444       if (S.getLangOptions().CPlusPlus) {
    445         contexts |= CXCompletionContext_EnumTag |
    446                     CXCompletionContext_UnionTag |
    447                     CXCompletionContext_StructTag |
    448                     CXCompletionContext_ClassTag |
    449                     CXCompletionContext_NestedNameSpecifier;
    450       }
    451       break;
    452     }
    453     case CodeCompletionContext::CCC_ObjCInstanceMessage: {
    454       contexts = CXCompletionContext_ObjCInstanceMessage;
    455       break;
    456     }
    457     case CodeCompletionContext::CCC_ObjCClassMessage: {
    458       contexts = CXCompletionContext_ObjCClassMessage;
    459       break;
    460     }
    461     case CodeCompletionContext::CCC_ObjCInterfaceName: {
    462       contexts = CXCompletionContext_ObjCInterface;
    463       break;
    464     }
    465     case CodeCompletionContext::CCC_ObjCCategoryName: {
    466       contexts = CXCompletionContext_ObjCCategory;
    467       break;
    468     }
    469     case CodeCompletionContext::CCC_Other:
    470     case CodeCompletionContext::CCC_ObjCInterface:
    471     case CodeCompletionContext::CCC_ObjCImplementation:
    472     case CodeCompletionContext::CCC_Name:
    473     case CodeCompletionContext::CCC_MacroName:
    474     case CodeCompletionContext::CCC_PreprocessorExpression:
    475     case CodeCompletionContext::CCC_PreprocessorDirective:
    476     case CodeCompletionContext::CCC_TypeQualifiers: {
    477       //Only Clang results should be accepted, so we'll set all of the other
    478       //context bits to 0 (i.e. the empty set)
    479       contexts = CXCompletionContext_Unexposed;
    480       break;
    481     }
    482     case CodeCompletionContext::CCC_Recovery: {
    483       //We don't know what the current context is, so we'll return unknown
    484       //This is the equivalent of setting all of the other context bits
    485       contexts = CXCompletionContext_Unknown;
    486       break;
    487     }
    488   }
    489   return contexts;
    490 }
    491 
    492 namespace {
    493   class CaptureCompletionResults : public CodeCompleteConsumer {
    494     AllocatedCXCodeCompleteResults &AllocatedResults;
    495     SmallVector<CXCompletionResult, 16> StoredResults;
    496     CXTranslationUnit *TU;
    497   public:
    498     CaptureCompletionResults(AllocatedCXCodeCompleteResults &Results,
    499                              CXTranslationUnit *TranslationUnit)
    500       : CodeCompleteConsumer(true, false, true, false),
    501         AllocatedResults(Results), TU(TranslationUnit) { }
    502     ~CaptureCompletionResults() { Finish(); }
    503 
    504     virtual void ProcessCodeCompleteResults(Sema &S,
    505                                             CodeCompletionContext Context,
    506                                             CodeCompletionResult *Results,
    507                                             unsigned NumResults) {
    508       StoredResults.reserve(StoredResults.size() + NumResults);
    509       for (unsigned I = 0; I != NumResults; ++I) {
    510         CodeCompletionString *StoredCompletion
    511           = Results[I].CreateCodeCompletionString(S,
    512                                       AllocatedResults.CodeCompletionAllocator);
    513 
    514         CXCompletionResult R;
    515         R.CursorKind = Results[I].CursorKind;
    516         R.CompletionString = StoredCompletion;
    517         StoredResults.push_back(R);
    518       }
    519 
    520       enum CodeCompletionContext::Kind contextKind = Context.getKind();
    521 
    522       AllocatedResults.ContextKind = contextKind;
    523       AllocatedResults.Contexts = getContextsForContextKind(contextKind, S);
    524 
    525       AllocatedResults.Selector = "";
    526       if (Context.getNumSelIdents() > 0) {
    527         for (unsigned i = 0; i < Context.getNumSelIdents(); i++) {
    528           IdentifierInfo *selIdent = Context.getSelIdents()[i];
    529           if (selIdent != NULL) {
    530             StringRef selectorString = Context.getSelIdents()[i]->getName();
    531             AllocatedResults.Selector += selectorString;
    532           }
    533           AllocatedResults.Selector += ":";
    534         }
    535       }
    536 
    537       QualType baseType = Context.getBaseType();
    538       NamedDecl *D = NULL;
    539 
    540       if (!baseType.isNull()) {
    541         // Get the declaration for a class/struct/union/enum type
    542         if (const TagType *Tag = baseType->getAs<TagType>())
    543           D = Tag->getDecl();
    544         // Get the @interface declaration for a (possibly-qualified) Objective-C
    545         // object pointer type, e.g., NSString*
    546         else if (const ObjCObjectPointerType *ObjPtr =
    547                  baseType->getAs<ObjCObjectPointerType>())
    548           D = ObjPtr->getInterfaceDecl();
    549         // Get the @interface declaration for an Objective-C object type
    550         else if (const ObjCObjectType *Obj = baseType->getAs<ObjCObjectType>())
    551           D = Obj->getInterface();
    552         // Get the class for a C++ injected-class-name
    553         else if (const InjectedClassNameType *Injected =
    554                  baseType->getAs<InjectedClassNameType>())
    555           D = Injected->getDecl();
    556       }
    557 
    558       if (D != NULL) {
    559         CXCursor cursor = cxcursor::MakeCXCursor(D, *TU);
    560 
    561         CXCursorKind cursorKind = clang_getCursorKind(cursor);
    562         CXString cursorUSR = clang_getCursorUSR(cursor);
    563 
    564         // Normally, clients of CXString shouldn't care whether or not
    565         // a CXString is managed by a pool or by explicitly malloc'ed memory.
    566         // However, there are cases when AllocatedResults outlives the
    567         // CXTranslationUnit.  This is a workaround that failure mode.
    568         if (cxstring::isManagedByPool(cursorUSR)) {
    569           CXString heapStr =
    570             cxstring::createCXString(clang_getCString(cursorUSR), true);
    571           clang_disposeString(cursorUSR);
    572           cursorUSR = heapStr;
    573         }
    574 
    575         AllocatedResults.ContainerKind = cursorKind;
    576         AllocatedResults.ContainerUSR = cursorUSR;
    577 
    578         const Type *type = baseType.getTypePtrOrNull();
    579         if (type != NULL) {
    580           AllocatedResults.ContainerIsIncomplete = type->isIncompleteType();
    581         }
    582         else {
    583           AllocatedResults.ContainerIsIncomplete = 1;
    584         }
    585       }
    586       else {
    587         AllocatedResults.ContainerKind = CXCursor_InvalidCode;
    588         AllocatedResults.ContainerUSR = createCXString("");
    589         AllocatedResults.ContainerIsIncomplete = 1;
    590       }
    591     }
    592 
    593     virtual void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
    594                                            OverloadCandidate *Candidates,
    595                                            unsigned NumCandidates) {
    596       StoredResults.reserve(StoredResults.size() + NumCandidates);
    597       for (unsigned I = 0; I != NumCandidates; ++I) {
    598         CodeCompletionString *StoredCompletion
    599           = Candidates[I].CreateSignatureString(CurrentArg, S,
    600                                       AllocatedResults.CodeCompletionAllocator);
    601 
    602         CXCompletionResult R;
    603         R.CursorKind = CXCursor_NotImplemented;
    604         R.CompletionString = StoredCompletion;
    605         StoredResults.push_back(R);
    606       }
    607     }
    608 
    609     virtual CodeCompletionAllocator &getAllocator() {
    610       return AllocatedResults.CodeCompletionAllocator;
    611     }
    612 
    613   private:
    614     void Finish() {
    615       AllocatedResults.Results = new CXCompletionResult [StoredResults.size()];
    616       AllocatedResults.NumResults = StoredResults.size();
    617       std::memcpy(AllocatedResults.Results, StoredResults.data(),
    618                   StoredResults.size() * sizeof(CXCompletionResult));
    619       StoredResults.clear();
    620     }
    621   };
    622 }
    623 
    624 extern "C" {
    625 struct CodeCompleteAtInfo {
    626   CXTranslationUnit TU;
    627   const char *complete_filename;
    628   unsigned complete_line;
    629   unsigned complete_column;
    630   struct CXUnsavedFile *unsaved_files;
    631   unsigned num_unsaved_files;
    632   unsigned options;
    633   CXCodeCompleteResults *result;
    634 };
    635 void clang_codeCompleteAt_Impl(void *UserData) {
    636   CodeCompleteAtInfo *CCAI = static_cast<CodeCompleteAtInfo*>(UserData);
    637   CXTranslationUnit TU = CCAI->TU;
    638   const char *complete_filename = CCAI->complete_filename;
    639   unsigned complete_line = CCAI->complete_line;
    640   unsigned complete_column = CCAI->complete_column;
    641   struct CXUnsavedFile *unsaved_files = CCAI->unsaved_files;
    642   unsigned num_unsaved_files = CCAI->num_unsaved_files;
    643   unsigned options = CCAI->options;
    644   CCAI->result = 0;
    645 
    646 #ifdef UDP_CODE_COMPLETION_LOGGER
    647 #ifdef UDP_CODE_COMPLETION_LOGGER_PORT
    648   const llvm::TimeRecord &StartTime =  llvm::TimeRecord::getCurrentTime();
    649 #endif
    650 #endif
    651 
    652   bool EnableLogging = getenv("LIBCLANG_CODE_COMPLETION_LOGGING") != 0;
    653 
    654   ASTUnit *AST = static_cast<ASTUnit *>(TU->TUData);
    655   if (!AST)
    656     return;
    657 
    658   ASTUnit::ConcurrencyCheck Check(*AST);
    659 
    660   // Perform the remapping of source files.
    661   SmallVector<ASTUnit::RemappedFile, 4> RemappedFiles;
    662   for (unsigned I = 0; I != num_unsaved_files; ++I) {
    663     StringRef Data(unsaved_files[I].Contents, unsaved_files[I].Length);
    664     const llvm::MemoryBuffer *Buffer
    665       = llvm::MemoryBuffer::getMemBufferCopy(Data, unsaved_files[I].Filename);
    666     RemappedFiles.push_back(std::make_pair(unsaved_files[I].Filename,
    667                                            Buffer));
    668   }
    669 
    670   if (EnableLogging) {
    671     // FIXME: Add logging.
    672   }
    673 
    674   // Parse the resulting source file to find code-completion results.
    675   AllocatedCXCodeCompleteResults *Results =
    676         new AllocatedCXCodeCompleteResults(AST->getFileSystemOpts());
    677   Results->Results = 0;
    678   Results->NumResults = 0;
    679 
    680   // Create a code-completion consumer to capture the results.
    681   CaptureCompletionResults Capture(*Results, &TU);
    682 
    683   // Perform completion.
    684   AST->CodeComplete(complete_filename, complete_line, complete_column,
    685                     RemappedFiles.data(), RemappedFiles.size(),
    686                     (options & CXCodeComplete_IncludeMacros),
    687                     (options & CXCodeComplete_IncludeCodePatterns),
    688                     Capture,
    689                     *Results->Diag, Results->LangOpts, *Results->SourceMgr,
    690                     *Results->FileMgr, Results->Diagnostics,
    691                     Results->TemporaryBuffers);
    692 
    693   // Keep a reference to the allocator used for cached global completions, so
    694   // that we can be sure that the memory used by our code completion strings
    695   // doesn't get freed due to subsequent reparses (while the code completion
    696   // results are still active).
    697   Results->CachedCompletionAllocator = AST->getCachedCompletionAllocator();
    698 
    699 
    700 
    701 #ifdef UDP_CODE_COMPLETION_LOGGER
    702 #ifdef UDP_CODE_COMPLETION_LOGGER_PORT
    703   const llvm::TimeRecord &EndTime =  llvm::TimeRecord::getCurrentTime();
    704   llvm::SmallString<256> LogResult;
    705   llvm::raw_svector_ostream os(LogResult);
    706 
    707   // Figure out the language and whether or not it uses PCH.
    708   const char *lang = 0;
    709   bool usesPCH = false;
    710 
    711   for (std::vector<const char*>::iterator I = argv.begin(), E = argv.end();
    712        I != E; ++I) {
    713     if (*I == 0)
    714       continue;
    715     if (strcmp(*I, "-x") == 0) {
    716       if (I + 1 != E) {
    717         lang = *(++I);
    718         continue;
    719       }
    720     }
    721     else if (strcmp(*I, "-include") == 0) {
    722       if (I+1 != E) {
    723         const char *arg = *(++I);
    724         llvm::SmallString<512> pchName;
    725         {
    726           llvm::raw_svector_ostream os(pchName);
    727           os << arg << ".pth";
    728         }
    729         pchName.push_back('\0');
    730         struct stat stat_results;
    731         if (stat(pchName.str().c_str(), &stat_results) == 0)
    732           usesPCH = true;
    733         continue;
    734       }
    735     }
    736   }
    737 
    738   os << "{ ";
    739   os << "\"wall\": " << (EndTime.getWallTime() - StartTime.getWallTime());
    740   os << ", \"numRes\": " << Results->NumResults;
    741   os << ", \"diags\": " << Results->Diagnostics.size();
    742   os << ", \"pch\": " << (usesPCH ? "true" : "false");
    743   os << ", \"lang\": \"" << (lang ? lang : "<unknown>") << '"';
    744   const char *name = getlogin();
    745   os << ", \"user\": \"" << (name ? name : "unknown") << '"';
    746   os << ", \"clangVer\": \"" << getClangFullVersion() << '"';
    747   os << " }";
    748 
    749   StringRef res = os.str();
    750   if (res.size() > 0) {
    751     do {
    752       // Setup the UDP socket.
    753       struct sockaddr_in servaddr;
    754       bzero(&servaddr, sizeof(servaddr));
    755       servaddr.sin_family = AF_INET;
    756       servaddr.sin_port = htons(UDP_CODE_COMPLETION_LOGGER_PORT);
    757       if (inet_pton(AF_INET, UDP_CODE_COMPLETION_LOGGER,
    758                     &servaddr.sin_addr) <= 0)
    759         break;
    760 
    761       int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    762       if (sockfd < 0)
    763         break;
    764 
    765       sendto(sockfd, res.data(), res.size(), 0,
    766              (struct sockaddr *)&servaddr, sizeof(servaddr));
    767       close(sockfd);
    768     }
    769     while (false);
    770   }
    771 #endif
    772 #endif
    773   CCAI->result = Results;
    774 }
    775 CXCodeCompleteResults *clang_codeCompleteAt(CXTranslationUnit TU,
    776                                             const char *complete_filename,
    777                                             unsigned complete_line,
    778                                             unsigned complete_column,
    779                                             struct CXUnsavedFile *unsaved_files,
    780                                             unsigned num_unsaved_files,
    781                                             unsigned options) {
    782   CodeCompleteAtInfo CCAI = { TU, complete_filename, complete_line,
    783                               complete_column, unsaved_files, num_unsaved_files,
    784                               options, 0 };
    785   llvm::CrashRecoveryContext CRC;
    786 
    787   if (!RunSafely(CRC, clang_codeCompleteAt_Impl, &CCAI)) {
    788     fprintf(stderr, "libclang: crash detected in code completion\n");
    789     static_cast<ASTUnit *>(TU->TUData)->setUnsafeToFree(true);
    790     return 0;
    791   } else if (getenv("LIBCLANG_RESOURCE_USAGE"))
    792     PrintLibclangResourceUsage(TU);
    793 
    794   return CCAI.result;
    795 }
    796 
    797 unsigned clang_defaultCodeCompleteOptions(void) {
    798   return CXCodeComplete_IncludeMacros;
    799 }
    800 
    801 void clang_disposeCodeCompleteResults(CXCodeCompleteResults *ResultsIn) {
    802   if (!ResultsIn)
    803     return;
    804 
    805   AllocatedCXCodeCompleteResults *Results
    806     = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
    807   delete Results;
    808 }
    809 
    810 unsigned
    811 clang_codeCompleteGetNumDiagnostics(CXCodeCompleteResults *ResultsIn) {
    812   AllocatedCXCodeCompleteResults *Results
    813     = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
    814   if (!Results)
    815     return 0;
    816 
    817   return Results->Diagnostics.size();
    818 }
    819 
    820 CXDiagnostic
    821 clang_codeCompleteGetDiagnostic(CXCodeCompleteResults *ResultsIn,
    822                                 unsigned Index) {
    823   AllocatedCXCodeCompleteResults *Results
    824     = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
    825   if (!Results || Index >= Results->Diagnostics.size())
    826     return 0;
    827 
    828   return new CXStoredDiagnostic(Results->Diagnostics[Index], Results->LangOpts);
    829 }
    830 
    831 unsigned long long
    832 clang_codeCompleteGetContexts(CXCodeCompleteResults *ResultsIn) {
    833   AllocatedCXCodeCompleteResults *Results
    834     = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
    835   if (!Results)
    836     return 0;
    837 
    838   return Results->Contexts;
    839 }
    840 
    841 enum CXCursorKind clang_codeCompleteGetContainerKind(
    842                                                CXCodeCompleteResults *ResultsIn,
    843                                                      unsigned *IsIncomplete) {
    844   AllocatedCXCodeCompleteResults *Results =
    845     static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
    846   if (!Results)
    847     return CXCursor_InvalidCode;
    848 
    849   if (IsIncomplete != NULL) {
    850     *IsIncomplete = Results->ContainerIsIncomplete;
    851   }
    852 
    853   return Results->ContainerKind;
    854 }
    855 
    856 CXString clang_codeCompleteGetContainerUSR(CXCodeCompleteResults *ResultsIn) {
    857   AllocatedCXCodeCompleteResults *Results =
    858     static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
    859   if (!Results)
    860     return createCXString("");
    861 
    862   return createCXString(clang_getCString(Results->ContainerUSR));
    863 }
    864 
    865 
    866 CXString clang_codeCompleteGetObjCSelector(CXCodeCompleteResults *ResultsIn) {
    867   AllocatedCXCodeCompleteResults *Results =
    868     static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
    869   if (!Results)
    870     return createCXString("");
    871 
    872   return createCXString(Results->Selector);
    873 }
    874 
    875 } // end extern "C"
    876 
    877 /// \brief Simple utility function that appends a \p New string to the given
    878 /// \p Old string, using the \p Buffer for storage.
    879 ///
    880 /// \param Old The string to which we are appending. This parameter will be
    881 /// updated to reflect the complete string.
    882 ///
    883 ///
    884 /// \param New The string to append to \p Old.
    885 ///
    886 /// \param Buffer A buffer that stores the actual, concatenated string. It will
    887 /// be used if the old string is already-non-empty.
    888 static void AppendToString(StringRef &Old, StringRef New,
    889                            llvm::SmallString<256> &Buffer) {
    890   if (Old.empty()) {
    891     Old = New;
    892     return;
    893   }
    894 
    895   if (Buffer.empty())
    896     Buffer.append(Old.begin(), Old.end());
    897   Buffer.append(New.begin(), New.end());
    898   Old = Buffer.str();
    899 }
    900 
    901 /// \brief Get the typed-text blocks from the given code-completion string
    902 /// and return them as a single string.
    903 ///
    904 /// \param String The code-completion string whose typed-text blocks will be
    905 /// concatenated.
    906 ///
    907 /// \param Buffer A buffer used for storage of the completed name.
    908 static StringRef GetTypedName(CodeCompletionString *String,
    909                                     llvm::SmallString<256> &Buffer) {
    910   StringRef Result;
    911   for (CodeCompletionString::iterator C = String->begin(), CEnd = String->end();
    912        C != CEnd; ++C) {
    913     if (C->Kind == CodeCompletionString::CK_TypedText)
    914       AppendToString(Result, C->Text, Buffer);
    915   }
    916 
    917   return Result;
    918 }
    919 
    920 namespace {
    921   struct OrderCompletionResults {
    922     bool operator()(const CXCompletionResult &XR,
    923                     const CXCompletionResult &YR) const {
    924       CodeCompletionString *X
    925         = (CodeCompletionString *)XR.CompletionString;
    926       CodeCompletionString *Y
    927         = (CodeCompletionString *)YR.CompletionString;
    928 
    929       llvm::SmallString<256> XBuffer;
    930       StringRef XText = GetTypedName(X, XBuffer);
    931       llvm::SmallString<256> YBuffer;
    932       StringRef YText = GetTypedName(Y, YBuffer);
    933 
    934       if (XText.empty() || YText.empty())
    935         return !XText.empty();
    936 
    937       int result = XText.compare_lower(YText);
    938       if (result < 0)
    939         return true;
    940       if (result > 0)
    941         return false;
    942 
    943       result = XText.compare(YText);
    944       return result < 0;
    945     }
    946   };
    947 }
    948 
    949 extern "C" {
    950   void clang_sortCodeCompletionResults(CXCompletionResult *Results,
    951                                        unsigned NumResults) {
    952     std::stable_sort(Results, Results + NumResults, OrderCompletionResults());
    953   }
    954 }
    955