Clang Project

clang_source_code/tools/libclang/CIndexCodeCompletion.cpp
1//===- CIndexCodeCompletion.cpp - Code Completion API hooks ---------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the Clang-C Source Indexing library hooks for
10// code completion.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CIndexer.h"
15#include "CIndexDiagnostic.h"
16#include "CLog.h"
17#include "CXCursor.h"
18#include "CXSourceLocation.h"
19#include "CXString.h"
20#include "CXTranslationUnit.h"
21#include "clang/AST/Decl.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/Type.h"
24#include "clang/Basic/FileManager.h"
25#include "clang/Basic/SourceManager.h"
26#include "clang/Frontend/ASTUnit.h"
27#include "clang/Frontend/CompilerInstance.h"
28#include "clang/Sema/CodeCompleteConsumer.h"
29#include "clang/Sema/Sema.h"
30#include "llvm/ADT/SmallString.h"
31#include "llvm/ADT/StringExtras.h"
32#include "llvm/Support/CrashRecoveryContext.h"
33#include "llvm/Support/FileSystem.h"
34#include "llvm/Support/FormatVariadic.h"
35#include "llvm/Support/MemoryBuffer.h"
36#include "llvm/Support/Program.h"
37#include "llvm/Support/Timer.h"
38#include "llvm/Support/raw_ostream.h"
39#include <atomic>
40#include <cstdio>
41#include <cstdlib>
42#include <string>
43
44
45#ifdef UDP_CODE_COMPLETION_LOGGER
46#include "clang/Basic/Version.h"
47#include <arpa/inet.h>
48#include <sys/socket.h>
49#include <sys/types.h>
50#include <unistd.h>
51#endif
52
53using namespace clang;
54using namespace clang::cxindex;
55
56enum CXCompletionChunkKind
57clang_getCompletionChunkKind(CXCompletionString completion_string,
58                             unsigned chunk_number) {
59  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
60  if (!CCStr || chunk_number >= CCStr->size())
61    return CXCompletionChunk_Text;
62
63  switch ((*CCStr)[chunk_number].Kind) {
64  case CodeCompletionString::CK_TypedText:
65    return CXCompletionChunk_TypedText;
66  case CodeCompletionString::CK_Text:
67    return CXCompletionChunk_Text;
68  case CodeCompletionString::CK_Optional:
69    return CXCompletionChunk_Optional;
70  case CodeCompletionString::CK_Placeholder:
71    return CXCompletionChunk_Placeholder;
72  case CodeCompletionString::CK_Informative:
73    return CXCompletionChunk_Informative;
74  case CodeCompletionString::CK_ResultType:
75    return CXCompletionChunk_ResultType;
76  case CodeCompletionString::CK_CurrentParameter:
77    return CXCompletionChunk_CurrentParameter;
78  case CodeCompletionString::CK_LeftParen:
79    return CXCompletionChunk_LeftParen;
80  case CodeCompletionString::CK_RightParen:
81    return CXCompletionChunk_RightParen;
82  case CodeCompletionString::CK_LeftBracket:
83    return CXCompletionChunk_LeftBracket;
84  case CodeCompletionString::CK_RightBracket:
85    return CXCompletionChunk_RightBracket;
86  case CodeCompletionString::CK_LeftBrace:
87    return CXCompletionChunk_LeftBrace;
88  case CodeCompletionString::CK_RightBrace:
89    return CXCompletionChunk_RightBrace;
90  case CodeCompletionString::CK_LeftAngle:
91    return CXCompletionChunk_LeftAngle;
92  case CodeCompletionString::CK_RightAngle:
93    return CXCompletionChunk_RightAngle;
94  case CodeCompletionString::CK_Comma:
95    return CXCompletionChunk_Comma;
96  case CodeCompletionString::CK_Colon:
97    return CXCompletionChunk_Colon;
98  case CodeCompletionString::CK_SemiColon:
99    return CXCompletionChunk_SemiColon;
100  case CodeCompletionString::CK_Equal:
101    return CXCompletionChunk_Equal;
102  case CodeCompletionString::CK_HorizontalSpace:
103    return CXCompletionChunk_HorizontalSpace;
104  case CodeCompletionString::CK_VerticalSpace:
105    return CXCompletionChunk_VerticalSpace;
106  }
107
108  llvm_unreachable("Invalid CompletionKind!");
109}
110
111CXString clang_getCompletionChunkText(CXCompletionString completion_string,
112                                      unsigned chunk_number) {
113  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
114  if (!CCStr || chunk_number >= CCStr->size())
115    return cxstring::createNull();
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 cxstring::createRef((*CCStr)[chunk_number].Text);
139      
140  case CodeCompletionString::CK_Optional:
141    // Note: treated as an empty text block.
142    return cxstring::createEmpty();
143  }
144
145  llvm_unreachable("Invalid CodeCompletionString Kind!");
146}
147
148
149CXCompletionString
150clang_getCompletionChunkCompletionString(CXCompletionString completion_string,
151                                         unsigned chunk_number) {
152  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
153  if (!CCStr || chunk_number >= CCStr->size())
154    return nullptr;
155
156  switch ((*CCStr)[chunk_number].Kind) {
157  case CodeCompletionString::CK_TypedText:
158  case CodeCompletionString::CK_Text:
159  case CodeCompletionString::CK_Placeholder:
160  case CodeCompletionString::CK_CurrentParameter:
161  case CodeCompletionString::CK_Informative:
162  case CodeCompletionString::CK_LeftParen:
163  case CodeCompletionString::CK_RightParen:
164  case CodeCompletionString::CK_LeftBracket:
165  case CodeCompletionString::CK_RightBracket:
166  case CodeCompletionString::CK_LeftBrace:
167  case CodeCompletionString::CK_RightBrace:
168  case CodeCompletionString::CK_LeftAngle:
169  case CodeCompletionString::CK_RightAngle:
170  case CodeCompletionString::CK_Comma:
171  case CodeCompletionString::CK_ResultType:
172  case CodeCompletionString::CK_Colon:
173  case CodeCompletionString::CK_SemiColon:
174  case CodeCompletionString::CK_Equal:
175  case CodeCompletionString::CK_HorizontalSpace:
176  case CodeCompletionString::CK_VerticalSpace:
177    return nullptr;
178
179  case CodeCompletionString::CK_Optional:
180    // Note: treated as an empty text block.
181    return (*CCStr)[chunk_number].Optional;
182  }
183
184  llvm_unreachable("Invalid CompletionKind!");
185}
186
187unsigned clang_getNumCompletionChunks(CXCompletionString completion_string) {
188  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
189  return CCStr? CCStr->size() : 0;
190}
191
192unsigned clang_getCompletionPriority(CXCompletionString completion_string) {
193  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
194  return CCStr? CCStr->getPriority() : unsigned(CCP_Unlikely);
195}
196  
197enum CXAvailabilityKind 
198clang_getCompletionAvailability(CXCompletionString completion_string) {
199  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
200  return CCStr? static_cast<CXAvailabilityKind>(CCStr->getAvailability())
201              : CXAvailability_Available;
202}
203
204unsigned clang_getCompletionNumAnnotations(CXCompletionString completion_string)
205{
206  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
207  return CCStr ? CCStr->getAnnotationCount() : 0;
208}
209
210CXString clang_getCompletionAnnotation(CXCompletionString completion_string,
211                                       unsigned annotation_number) {
212  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
213  return CCStr ? cxstring::createRef(CCStr->getAnnotation(annotation_number))
214               : cxstring::createNull();
215}
216
217CXString
218clang_getCompletionParent(CXCompletionString completion_string,
219                          CXCursorKind *kind) {
220  if (kind)
221    *kind = CXCursor_NotImplemented;
222  
223  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
224  if (!CCStr)
225    return cxstring::createNull();
226  
227  return cxstring::createRef(CCStr->getParentContextName());
228}
229
230CXString
231clang_getCompletionBriefComment(CXCompletionString completion_string) {
232  CodeCompletionString *CCStr = (CodeCompletionString *)completion_string;
233
234  if (!CCStr)
235    return cxstring::createNull();
236
237  return cxstring::createRef(CCStr->getBriefComment());
238}
239
240namespace {
241
242/// The CXCodeCompleteResults structure we allocate internally;
243/// the client only sees the initial CXCodeCompleteResults structure.
244///
245/// Normally, clients of CXString shouldn't care whether or not a CXString is
246/// managed by a pool or by explicitly malloc'ed memory.  But
247/// AllocatedCXCodeCompleteResults outlives the CXTranslationUnit, so we can
248/// not rely on the StringPool in the TU.
249struct AllocatedCXCodeCompleteResults : public CXCodeCompleteResults {
250  AllocatedCXCodeCompleteResults(IntrusiveRefCntPtr<FileManager> FileMgr);
251  ~AllocatedCXCodeCompleteResults();
252  
253  /// Diagnostics produced while performing code completion.
254  SmallVector<StoredDiagnostic, 8> Diagnostics;
255
256  /// Allocated API-exposed wrappters for Diagnostics.
257  SmallVector<CXStoredDiagnostic *, 8> DiagnosticsWrappers;
258
259  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts;
260  
261  /// Diag object
262  IntrusiveRefCntPtr<DiagnosticsEngine> Diag;
263  
264  /// Language options used to adjust source locations.
265  LangOptions LangOpts;
266
267  /// File manager, used for diagnostics.
268  IntrusiveRefCntPtr<FileManager> FileMgr;
269
270  /// Source manager, used for diagnostics.
271  IntrusiveRefCntPtr<SourceManager> SourceMgr;
272  
273  /// Temporary buffers that will be deleted once we have finished with
274  /// the code-completion results.
275  SmallVector<const llvm::MemoryBuffer *, 1> TemporaryBuffers;
276  
277  /// Allocator used to store globally cached code-completion results.
278  std::shared_ptr<clang::GlobalCodeCompletionAllocator>
279      CachedCompletionAllocator;
280
281  /// Allocator used to store code completion results.
282  std::shared_ptr<clang::GlobalCodeCompletionAllocator> CodeCompletionAllocator;
283
284  /// Context under which completion occurred.
285  enum clang::CodeCompletionContext::Kind ContextKind;
286  
287  /// A bitfield representing the acceptable completions for the
288  /// current context.
289  unsigned long long Contexts;
290  
291  /// The kind of the container for the current context for completions.
292  enum CXCursorKind ContainerKind;
293
294  /// The USR of the container for the current context for completions.
295  std::string ContainerUSR;
296
297  /// a boolean value indicating whether there is complete information
298  /// about the container
299  unsigned ContainerIsIncomplete;
300  
301  /// A string containing the Objective-C selector entered thus far for a
302  /// message send.
303  std::string Selector;
304
305  /// Vector of fix-its for each completion result that *must* be applied
306  /// before that result for the corresponding completion item.
307  std::vector<std::vector<FixItHint>> FixItsVector;
308};
309
310} // end anonymous namespace
311
312unsigned clang_getCompletionNumFixIts(CXCodeCompleteResults *results,
313                                      unsigned completion_index) {
314  AllocatedCXCodeCompleteResults *allocated_results = (AllocatedCXCodeCompleteResults *)results;
315
316  if (!allocated_results || allocated_results->FixItsVector.size() <= completion_index)
317    return 0;
318
319  return static_cast<unsigned>(allocated_results->FixItsVector[completion_index].size());
320}
321
322CXString clang_getCompletionFixIt(CXCodeCompleteResults *results,
323                                  unsigned completion_index,
324                                  unsigned fixit_index,
325                                  CXSourceRange *replacement_range) {
326  AllocatedCXCodeCompleteResults *allocated_results = (AllocatedCXCodeCompleteResults *)results;
327
328  if (!allocated_results || allocated_results->FixItsVector.size() <= completion_index) {
329    if (replacement_range)
330      *replacement_range = clang_getNullRange();
331    return cxstring::createNull();
332  }
333
334  ArrayRef<FixItHint> FixIts = allocated_results->FixItsVector[completion_index];
335  if (FixIts.size() <= fixit_index) {
336    if (replacement_range)
337      *replacement_range = clang_getNullRange();
338    return cxstring::createNull();
339  }
340
341  const FixItHint &FixIt = FixIts[fixit_index];
342  if (replacement_range) {
343    *replacement_range = cxloc::translateSourceRange(
344        *allocated_results->SourceMgr, allocated_results->LangOpts,
345        FixIt.RemoveRange);
346  }
347
348  return cxstring::createRef(FixIt.CodeToInsert.c_str());
349}
350
351/// Tracks the number of code-completion result objects that are 
352/// currently active.
353///
354/// Used for debugging purposes only.
355static std::atomic<unsigned> CodeCompletionResultObjects;
356
357AllocatedCXCodeCompleteResults::AllocatedCXCodeCompleteResults(
358    IntrusiveRefCntPtr<FileManager> FileMgr)
359    : CXCodeCompleteResults(), DiagOpts(new DiagnosticOptions),
360      Diag(new DiagnosticsEngine(
361          IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs), &*DiagOpts)),
362      FileMgr(std::move(FileMgr)),
363      SourceMgr(new SourceManager(*Diag, *this->FileMgr)),
364      CodeCompletionAllocator(
365          std::make_shared<clang::GlobalCodeCompletionAllocator>()),
366      Contexts(CXCompletionContext_Unknown),
367      ContainerKind(CXCursor_InvalidCode), ContainerIsIncomplete(1) {
368  if (getenv("LIBCLANG_OBJTRACKING"))
369    fprintf(stderr, "+++ %u completion results\n",
370            ++CodeCompletionResultObjects);
371}
372  
373AllocatedCXCodeCompleteResults::~AllocatedCXCodeCompleteResults() {
374  llvm::DeleteContainerPointers(DiagnosticsWrappers);
375  delete [] Results;
376
377  for (unsigned I = 0, N = TemporaryBuffers.size(); I != N; ++I)
378    delete TemporaryBuffers[I];
379
380  if (getenv("LIBCLANG_OBJTRACKING"))
381    fprintf(stderr, "--- %u completion results\n",
382            --CodeCompletionResultObjects);
383}
384
385static unsigned long long getContextsForContextKind(
386                                          enum CodeCompletionContext::Kind kind, 
387                                                    Sema &S) {
388  unsigned long long contexts = 0;
389  switch (kind) {
390    case CodeCompletionContext::CCC_OtherWithMacros: {
391      //We can allow macros here, but we don't know what else is permissible
392      //So we'll say the only thing permissible are macros
393      contexts = CXCompletionContext_MacroName;
394      break;
395    }
396    case CodeCompletionContext::CCC_TopLevel:
397    case CodeCompletionContext::CCC_ObjCIvarList:
398    case CodeCompletionContext::CCC_ClassStructUnion:
399    case CodeCompletionContext::CCC_Type: {
400      contexts = CXCompletionContext_AnyType | 
401                 CXCompletionContext_ObjCInterface;
402      if (S.getLangOpts().CPlusPlus) {
403        contexts |= CXCompletionContext_EnumTag |
404                    CXCompletionContext_UnionTag |
405                    CXCompletionContext_StructTag |
406                    CXCompletionContext_ClassTag |
407                    CXCompletionContext_NestedNameSpecifier;
408      }
409      break;
410    }
411    case CodeCompletionContext::CCC_Statement: {
412      contexts = CXCompletionContext_AnyType |
413                 CXCompletionContext_ObjCInterface |
414                 CXCompletionContext_AnyValue;
415      if (S.getLangOpts().CPlusPlus) {
416        contexts |= CXCompletionContext_EnumTag |
417                    CXCompletionContext_UnionTag |
418                    CXCompletionContext_StructTag |
419                    CXCompletionContext_ClassTag |
420                    CXCompletionContext_NestedNameSpecifier;
421      }
422      break;
423    }
424    case CodeCompletionContext::CCC_Expression: {
425      contexts = CXCompletionContext_AnyValue;
426      if (S.getLangOpts().CPlusPlus) {
427        contexts |= CXCompletionContext_AnyType |
428                    CXCompletionContext_ObjCInterface |
429                    CXCompletionContext_EnumTag |
430                    CXCompletionContext_UnionTag |
431                    CXCompletionContext_StructTag |
432                    CXCompletionContext_ClassTag |
433                    CXCompletionContext_NestedNameSpecifier;
434      }
435      break;
436    }
437    case CodeCompletionContext::CCC_ObjCMessageReceiver: {
438      contexts = CXCompletionContext_ObjCObjectValue |
439                 CXCompletionContext_ObjCSelectorValue |
440                 CXCompletionContext_ObjCInterface;
441      if (S.getLangOpts().CPlusPlus) {
442        contexts |= CXCompletionContext_CXXClassTypeValue |
443                    CXCompletionContext_AnyType |
444                    CXCompletionContext_EnumTag |
445                    CXCompletionContext_UnionTag |
446                    CXCompletionContext_StructTag |
447                    CXCompletionContext_ClassTag |
448                    CXCompletionContext_NestedNameSpecifier;
449      }
450      break;
451    }
452    case CodeCompletionContext::CCC_DotMemberAccess: {
453      contexts = CXCompletionContext_DotMemberAccess;
454      break;
455    }
456    case CodeCompletionContext::CCC_ArrowMemberAccess: {
457      contexts = CXCompletionContext_ArrowMemberAccess;
458      break;
459    }
460    case CodeCompletionContext::CCC_ObjCPropertyAccess: {
461      contexts = CXCompletionContext_ObjCPropertyAccess;
462      break;
463    }
464    case CodeCompletionContext::CCC_EnumTag: {
465      contexts = CXCompletionContext_EnumTag |
466                 CXCompletionContext_NestedNameSpecifier;
467      break;
468    }
469    case CodeCompletionContext::CCC_UnionTag: {
470      contexts = CXCompletionContext_UnionTag |
471                 CXCompletionContext_NestedNameSpecifier;
472      break;
473    }
474    case CodeCompletionContext::CCC_ClassOrStructTag: {
475      contexts = CXCompletionContext_StructTag |
476                 CXCompletionContext_ClassTag |
477                 CXCompletionContext_NestedNameSpecifier;
478      break;
479    }
480    case CodeCompletionContext::CCC_ObjCProtocolName: {
481      contexts = CXCompletionContext_ObjCProtocol;
482      break;
483    }
484    case CodeCompletionContext::CCC_Namespace: {
485      contexts = CXCompletionContext_Namespace;
486      break;
487    }
488    case CodeCompletionContext::CCC_SymbolOrNewName:
489    case CodeCompletionContext::CCC_Symbol: {
490      contexts = CXCompletionContext_NestedNameSpecifier;
491      break;
492    }
493    case CodeCompletionContext::CCC_MacroNameUse: {
494      contexts = CXCompletionContext_MacroName;
495      break;
496    }
497    case CodeCompletionContext::CCC_NaturalLanguage: {
498      contexts = CXCompletionContext_NaturalLanguage;
499      break;
500    }
501    case CodeCompletionContext::CCC_IncludedFile: {
502      contexts = CXCompletionContext_IncludedFile;
503      break;
504    }
505    case CodeCompletionContext::CCC_SelectorName: {
506      contexts = CXCompletionContext_ObjCSelectorName;
507      break;
508    }
509    case CodeCompletionContext::CCC_ParenthesizedExpression: {
510      contexts = CXCompletionContext_AnyType |
511                 CXCompletionContext_ObjCInterface |
512                 CXCompletionContext_AnyValue;
513      if (S.getLangOpts().CPlusPlus) {
514        contexts |= CXCompletionContext_EnumTag |
515                    CXCompletionContext_UnionTag |
516                    CXCompletionContext_StructTag |
517                    CXCompletionContext_ClassTag |
518                    CXCompletionContext_NestedNameSpecifier;
519      }
520      break;
521    }
522    case CodeCompletionContext::CCC_ObjCInstanceMessage: {
523      contexts = CXCompletionContext_ObjCInstanceMessage;
524      break;
525    }
526    case CodeCompletionContext::CCC_ObjCClassMessage: {
527      contexts = CXCompletionContext_ObjCClassMessage;
528      break;
529    }
530    case CodeCompletionContext::CCC_ObjCInterfaceName: {
531      contexts = CXCompletionContext_ObjCInterface;
532      break;
533    }
534    case CodeCompletionContext::CCC_ObjCCategoryName: {
535      contexts = CXCompletionContext_ObjCCategory;
536      break;
537    }
538    case CodeCompletionContext::CCC_Other:
539    case CodeCompletionContext::CCC_ObjCInterface:
540    case CodeCompletionContext::CCC_ObjCImplementation:
541    case CodeCompletionContext::CCC_NewName:
542    case CodeCompletionContext::CCC_MacroName:
543    case CodeCompletionContext::CCC_PreprocessorExpression:
544    case CodeCompletionContext::CCC_PreprocessorDirective:
545    case CodeCompletionContext::CCC_TypeQualifiers: {
546      //Only Clang results should be accepted, so we'll set all of the other
547      //context bits to 0 (i.e. the empty set)
548      contexts = CXCompletionContext_Unexposed;
549      break;
550    }
551    case CodeCompletionContext::CCC_Recovery: {
552      //We don't know what the current context is, so we'll return unknown
553      //This is the equivalent of setting all of the other context bits
554      contexts = CXCompletionContext_Unknown;
555      break;
556    }
557  }
558  return contexts;
559}
560
561namespace {
562  class CaptureCompletionResults : public CodeCompleteConsumer {
563    AllocatedCXCodeCompleteResults &AllocatedResults;
564    CodeCompletionTUInfo CCTUInfo;
565    SmallVector<CXCompletionResult, 16> StoredResults;
566    CXTranslationUnit *TU;
567  public:
568    CaptureCompletionResults(const CodeCompleteOptions &Opts,
569                             AllocatedCXCodeCompleteResults &Results,
570                             CXTranslationUnit *TranslationUnit)
571      : CodeCompleteConsumer(Opts, false), 
572        AllocatedResults(Results), CCTUInfo(Results.CodeCompletionAllocator),
573        TU(TranslationUnit) { }
574    ~CaptureCompletionResults() override { Finish(); }
575
576    void ProcessCodeCompleteResults(Sema &S, 
577                                    CodeCompletionContext Context,
578                                    CodeCompletionResult *Results,
579                                    unsigned NumResults) override {
580      StoredResults.reserve(StoredResults.size() + NumResults);
581      if (includeFixIts())
582        AllocatedResults.FixItsVector.reserve(NumResults);
583      for (unsigned I = 0; I != NumResults; ++I) {
584        CodeCompletionString *StoredCompletion
585          = Results[I].CreateCodeCompletionString(S, Context, getAllocator(),
586                                                  getCodeCompletionTUInfo(),
587                                                  includeBriefComments());
588        
589        CXCompletionResult R;
590        R.CursorKind = Results[I].CursorKind;
591        R.CompletionString = StoredCompletion;
592        StoredResults.push_back(R);
593        if (includeFixIts())
594          AllocatedResults.FixItsVector.emplace_back(std::move(Results[I].FixIts));
595      }
596
597      enum CodeCompletionContext::Kind contextKind = Context.getKind();
598      
599      AllocatedResults.ContextKind = contextKind;
600      AllocatedResults.Contexts = getContextsForContextKind(contextKind, S);
601      
602      AllocatedResults.Selector = "";
603      ArrayRef<IdentifierInfo *> SelIdents = Context.getSelIdents();
604      for (ArrayRef<IdentifierInfo *>::iterator I = SelIdents.begin(),
605                                                E = SelIdents.end();
606           I != E; ++I) {
607        if (IdentifierInfo *selIdent = *I)
608          AllocatedResults.Selector += selIdent->getName();
609        AllocatedResults.Selector += ":";
610      }
611      
612      QualType baseType = Context.getBaseType();
613      NamedDecl *D = nullptr;
614
615      if (!baseType.isNull()) {
616        // Get the declaration for a class/struct/union/enum type
617        if (const TagType *Tag = baseType->getAs<TagType>())
618          D = Tag->getDecl();
619        // Get the @interface declaration for a (possibly-qualified) Objective-C
620        // object pointer type, e.g., NSString*
621        else if (const ObjCObjectPointerType *ObjPtr = 
622                 baseType->getAs<ObjCObjectPointerType>())
623          D = ObjPtr->getInterfaceDecl();
624        // Get the @interface declaration for an Objective-C object type
625        else if (const ObjCObjectType *Obj = baseType->getAs<ObjCObjectType>())
626          D = Obj->getInterface();
627        // Get the class for a C++ injected-class-name
628        else if (const InjectedClassNameType *Injected =
629                 baseType->getAs<InjectedClassNameType>())
630          D = Injected->getDecl();
631      }
632
633      if (D != nullptr) {
634        CXCursor cursor = cxcursor::MakeCXCursor(D, *TU);
635
636        AllocatedResults.ContainerKind = clang_getCursorKind(cursor);
637
638        CXString CursorUSR = clang_getCursorUSR(cursor);
639        AllocatedResults.ContainerUSR = clang_getCString(CursorUSR);
640        clang_disposeString(CursorUSR);
641
642        const Type *type = baseType.getTypePtrOrNull();
643        if (type) {
644          AllocatedResults.ContainerIsIncomplete = type->isIncompleteType();
645        }
646        else {
647          AllocatedResults.ContainerIsIncomplete = 1;
648        }
649      }
650      else {
651        AllocatedResults.ContainerKind = CXCursor_InvalidCode;
652        AllocatedResults.ContainerUSR.clear();
653        AllocatedResults.ContainerIsIncomplete = 1;
654      }
655    }
656
657    void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
658                                   OverloadCandidate *Candidates,
659                                   unsigned NumCandidates,
660                                   SourceLocation OpenParLoc) override {
661      StoredResults.reserve(StoredResults.size() + NumCandidates);
662      for (unsigned I = 0; I != NumCandidates; ++I) {
663        CodeCompletionString *StoredCompletion
664          = Candidates[I].CreateSignatureString(CurrentArg, S, getAllocator(),
665                                                getCodeCompletionTUInfo(),
666                                                includeBriefComments());
667        
668        CXCompletionResult R;
669        R.CursorKind = CXCursor_OverloadCandidate;
670        R.CompletionString = StoredCompletion;
671        StoredResults.push_back(R);
672      }
673    }
674
675    CodeCompletionAllocator &getAllocator() override {
676      return *AllocatedResults.CodeCompletionAllocator;
677    }
678
679    CodeCompletionTUInfo &getCodeCompletionTUInfo() override { return CCTUInfo;}
680
681  private:
682    void Finish() {
683      AllocatedResults.Results = new CXCompletionResult [StoredResults.size()];
684      AllocatedResults.NumResults = StoredResults.size();
685      std::memcpy(AllocatedResults.Results, StoredResults.data(), 
686                  StoredResults.size() * sizeof(CXCompletionResult));
687      StoredResults.clear();
688    }
689  };
690}
691
692static CXCodeCompleteResults *
693clang_codeCompleteAt_Impl(CXTranslationUnit TU, const char *complete_filename,
694                          unsigned complete_line, unsigned complete_column,
695                          ArrayRef<CXUnsavedFile> unsaved_files,
696                          unsigned options) {
697  bool IncludeBriefComments = options & CXCodeComplete_IncludeBriefComments;
698  bool SkipPreamble = options & CXCodeComplete_SkipPreamble;
699  bool IncludeFixIts = options & CXCodeComplete_IncludeCompletionsWithFixIts;
700
701#ifdef UDP_CODE_COMPLETION_LOGGER
702#ifdef UDP_CODE_COMPLETION_LOGGER_PORT
703  const llvm::TimeRecord &StartTime =  llvm::TimeRecord::getCurrentTime();
704#endif
705#endif
706  bool EnableLogging = getenv("LIBCLANG_CODE_COMPLETION_LOGGING") != nullptr;
707
708  if (cxtu::isNotUsableTU(TU)) {
709    LOG_BAD_TU(TU);
710    return nullptr;
711  }
712
713  ASTUnit *AST = cxtu::getASTUnit(TU);
714  if (!AST)
715    return nullptr;
716
717  CIndexer *CXXIdx = TU->CIdx;
718  if (CXXIdx->isOptEnabled(CXGlobalOpt_ThreadBackgroundPriorityForEditing))
719    setThreadBackgroundPriority();
720
721  ASTUnit::ConcurrencyCheck Check(*AST);
722
723  // Perform the remapping of source files.
724  SmallVector<ASTUnit::RemappedFile, 4> RemappedFiles;
725
726  for (auto &UF : unsaved_files) {
727    std::unique_ptr<llvm::MemoryBuffer> MB =
728        llvm::MemoryBuffer::getMemBufferCopy(getContents(UF), UF.Filename);
729    RemappedFiles.push_back(std::make_pair(UF.Filename, MB.release()));
730  }
731
732  if (EnableLogging) {
733    // FIXME: Add logging.
734  }
735
736  // Parse the resulting source file to find code-completion results.
737  AllocatedCXCodeCompleteResults *Results = new AllocatedCXCodeCompleteResults(
738      &AST->getFileManager());
739  Results->Results = nullptr;
740  Results->NumResults = 0;
741  
742  // Create a code-completion consumer to capture the results.
743  CodeCompleteOptions Opts;
744  Opts.IncludeBriefComments = IncludeBriefComments;
745  Opts.LoadExternal = !SkipPreamble;
746  Opts.IncludeFixIts = IncludeFixIts;
747  CaptureCompletionResults Capture(Opts, *Results, &TU);
748
749  // Perform completion.
750  std::vector<const char *> CArgs;
751  for (const auto &Arg : TU->Arguments)
752    CArgs.push_back(Arg.c_str());
753  std::string CompletionInvocation =
754      llvm::formatv("-code-completion-at={0}:{1}:{2}", complete_filename,
755                    complete_line, complete_column)
756          .str();
757  LibclangInvocationReporter InvocationReporter(
758      *CXXIdx, LibclangInvocationReporter::OperationKind::CompletionOperation,
759      TU->ParsingOptions, CArgs, CompletionInvocation, unsaved_files);
760  AST->CodeComplete(complete_filename, complete_line, complete_column,
761                    RemappedFiles, (options & CXCodeComplete_IncludeMacros),
762                    (options & CXCodeComplete_IncludeCodePatterns),
763                    IncludeBriefComments, Capture,
764                    CXXIdx->getPCHContainerOperations(), *Results->Diag,
765                    Results->LangOpts, *Results->SourceMgr, *Results->FileMgr,
766                    Results->Diagnostics, Results->TemporaryBuffers);
767
768  Results->DiagnosticsWrappers.resize(Results->Diagnostics.size());
769
770  // Keep a reference to the allocator used for cached global completions, so
771  // that we can be sure that the memory used by our code completion strings
772  // doesn't get freed due to subsequent reparses (while the code completion
773  // results are still active).
774  Results->CachedCompletionAllocator = AST->getCachedCompletionAllocator();
775
776  
777
778#ifdef UDP_CODE_COMPLETION_LOGGER
779#ifdef UDP_CODE_COMPLETION_LOGGER_PORT
780  const llvm::TimeRecord &EndTime =  llvm::TimeRecord::getCurrentTime();
781  SmallString<256> LogResult;
782  llvm::raw_svector_ostream os(LogResult);
783
784  // Figure out the language and whether or not it uses PCH.
785  const char *lang = 0;
786  bool usesPCH = false;
787
788  for (std::vector<const char*>::iterator I = argv.begin(), E = argv.end();
789       I != E; ++I) {
790    if (*I == 0)
791      continue;
792    if (strcmp(*I, "-x") == 0) {
793      if (I + 1 != E) {
794        lang = *(++I);
795        continue;
796      }
797    }
798    else if (strcmp(*I, "-include") == 0) {
799      if (I+1 != E) {
800        const char *arg = *(++I);
801        SmallString<512> pchName;
802        {
803          llvm::raw_svector_ostream os(pchName);
804          os << arg << ".pth";
805        }
806        pchName.push_back('\0');
807        struct stat stat_results;
808        if (stat(pchName.str().c_str(), &stat_results) == 0)
809          usesPCH = true;
810        continue;
811      }
812    }
813  }
814
815  os << "{ ";
816  os << "\"wall\": " << (EndTime.getWallTime() - StartTime.getWallTime());
817  os << ", \"numRes\": " << Results->NumResults;
818  os << ", \"diags\": " << Results->Diagnostics.size();
819  os << ", \"pch\": " << (usesPCH ? "true" : "false");
820  os << ", \"lang\": \"" << (lang ? lang : "<unknown>") << '"';
821  const char *name = getlogin();
822  os << ", \"user\": \"" << (name ? name : "unknown") << '"';
823  os << ", \"clangVer\": \"" << getClangFullVersion() << '"';
824  os << " }";
825
826  StringRef res = os.str();
827  if (res.size() > 0) {
828    do {
829      // Setup the UDP socket.
830      struct sockaddr_in servaddr;
831      bzero(&servaddr, sizeof(servaddr));
832      servaddr.sin_family = AF_INET;
833      servaddr.sin_port = htons(UDP_CODE_COMPLETION_LOGGER_PORT);
834      if (inet_pton(AF_INET, UDP_CODE_COMPLETION_LOGGER,
835                    &servaddr.sin_addr) <= 0)
836        break;
837
838      int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
839      if (sockfd < 0)
840        break;
841
842      sendto(sockfd, res.data(), res.size(), 0,
843             (struct sockaddr *)&servaddr, sizeof(servaddr));
844      close(sockfd);
845    }
846    while (false);
847  }
848#endif
849#endif
850  return Results;
851}
852
853CXCodeCompleteResults *clang_codeCompleteAt(CXTranslationUnit TU,
854                                            const char *complete_filename,
855                                            unsigned complete_line,
856                                            unsigned complete_column,
857                                            struct CXUnsavedFile *unsaved_files,
858                                            unsigned num_unsaved_files,
859                                            unsigned options) {
860  LOG_FUNC_SECTION {
861    *Log << TU << ' '
862         << complete_filename << ':' << complete_line << ':' << complete_column;
863  }
864
865  if (num_unsaved_files && !unsaved_files)
866    return nullptr;
867
868  CXCodeCompleteResults *result;
869  auto CodeCompleteAtImpl = [=, &result]() {
870    result = clang_codeCompleteAt_Impl(
871        TU, complete_filename, complete_line, complete_column,
872        llvm::makeArrayRef(unsaved_files, num_unsaved_files), options);
873  };
874
875  llvm::CrashRecoveryContext CRC;
876
877  if (!RunSafely(CRC, CodeCompleteAtImpl)) {
878    fprintf(stderr, "libclang: crash detected in code completion\n");
879    cxtu::getASTUnit(TU)->setUnsafeToFree(true);
880    return nullptr;
881  } else if (getenv("LIBCLANG_RESOURCE_USAGE"))
882    PrintLibclangResourceUsage(TU);
883
884  return result;
885}
886
887unsigned clang_defaultCodeCompleteOptions(void) {
888  return CXCodeComplete_IncludeMacros;
889}
890
891void clang_disposeCodeCompleteResults(CXCodeCompleteResults *ResultsIn) {
892  if (!ResultsIn)
893    return;
894
895  AllocatedCXCodeCompleteResults *Results
896    = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
897  delete Results;
898}
899  
900unsigned 
901clang_codeCompleteGetNumDiagnostics(CXCodeCompleteResults *ResultsIn) {
902  AllocatedCXCodeCompleteResults *Results
903    = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
904  if (!Results)
905    return 0;
906
907  return Results->Diagnostics.size();
908}
909
910CXDiagnostic 
911clang_codeCompleteGetDiagnostic(CXCodeCompleteResults *ResultsIn,
912                                unsigned Index) {
913  AllocatedCXCodeCompleteResults *Results
914    = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
915  if (!Results || Index >= Results->Diagnostics.size())
916    return nullptr;
917
918  CXStoredDiagnostic *Diag = Results->DiagnosticsWrappers[Index];
919  if (!Diag)
920    Results->DiagnosticsWrappers[Index] = Diag =
921        new CXStoredDiagnostic(Results->Diagnostics[Index], Results->LangOpts);
922  return Diag;
923}
924
925unsigned long long
926clang_codeCompleteGetContexts(CXCodeCompleteResults *ResultsIn) {
927  AllocatedCXCodeCompleteResults *Results
928    = static_cast<AllocatedCXCodeCompleteResults*>(ResultsIn);
929  if (!Results)
930    return 0;
931  
932  return Results->Contexts;
933}
934
935enum CXCursorKind clang_codeCompleteGetContainerKind(
936                                               CXCodeCompleteResults *ResultsIn,
937                                                     unsigned *IsIncomplete) {
938  AllocatedCXCodeCompleteResults *Results =
939    static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
940  if (!Results)
941    return CXCursor_InvalidCode;
942
943  if (IsIncomplete != nullptr) {
944    *IsIncomplete = Results->ContainerIsIncomplete;
945  }
946  
947  return Results->ContainerKind;
948}
949  
950CXString clang_codeCompleteGetContainerUSR(CXCodeCompleteResults *ResultsIn) {
951  AllocatedCXCodeCompleteResults *Results =
952    static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
953  if (!Results)
954    return cxstring::createEmpty();
955
956  return cxstring::createRef(Results->ContainerUSR.c_str());
957}
958
959  
960CXString clang_codeCompleteGetObjCSelector(CXCodeCompleteResults *ResultsIn) {
961  AllocatedCXCodeCompleteResults *Results =
962    static_cast<AllocatedCXCodeCompleteResults *>(ResultsIn);
963  if (!Results)
964    return cxstring::createEmpty();
965  
966  return cxstring::createDup(Results->Selector);
967}
968  
969/// Simple utility function that appends a \p New string to the given
970/// \p Old string, using the \p Buffer for storage.
971///
972/// \param Old The string to which we are appending. This parameter will be
973/// updated to reflect the complete string.
974///
975///
976/// \param New The string to append to \p Old.
977///
978/// \param Buffer A buffer that stores the actual, concatenated string. It will
979/// be used if the old string is already-non-empty.
980static void AppendToString(StringRef &Old, StringRef New,
981                           SmallString<256> &Buffer) {
982  if (Old.empty()) {
983    Old = New;
984    return;
985  }
986  
987  if (Buffer.empty())
988    Buffer.append(Old.begin(), Old.end());
989  Buffer.append(New.begin(), New.end());
990  Old = Buffer.str();
991}
992
993/// Get the typed-text blocks from the given code-completion string
994/// and return them as a single string.
995///
996/// \param String The code-completion string whose typed-text blocks will be
997/// concatenated.
998///
999/// \param Buffer A buffer used for storage of the completed name.
1000static StringRef GetTypedName(CodeCompletionString *String,
1001                                    SmallString<256> &Buffer) {
1002  StringRef Result;
1003  for (CodeCompletionString::iterator C = String->begin(), CEnd = String->end();
1004       C != CEnd; ++C) {
1005    if (C->Kind == CodeCompletionString::CK_TypedText)
1006      AppendToString(Result, C->Text, Buffer);
1007  }
1008  
1009  return Result;
1010}
1011
1012namespace {
1013  struct OrderCompletionResults {
1014    bool operator()(const CXCompletionResult &XR, 
1015                    const CXCompletionResult &YR) const {
1016      CodeCompletionString *X
1017        = (CodeCompletionString *)XR.CompletionString;
1018      CodeCompletionString *Y
1019        = (CodeCompletionString *)YR.CompletionString;
1020
1021      SmallString<256> XBuffer;
1022      StringRef XText = GetTypedName(X, XBuffer);
1023      SmallString<256> YBuffer;
1024      StringRef YText = GetTypedName(Y, YBuffer);
1025      
1026      if (XText.empty() || YText.empty())
1027        return !XText.empty();
1028            
1029      int result = XText.compare_lower(YText);
1030      if (result < 0)
1031        return true;
1032      if (result > 0)
1033        return false;
1034      
1035      result = XText.compare(YText);
1036      return result < 0;
1037    }
1038  };
1039}
1040
1041void clang_sortCodeCompletionResults(CXCompletionResult *Results,
1042                                     unsigned NumResults) {
1043  std::stable_sort(Results, Results + NumResults, OrderCompletionResults());
1044}
1045
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