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