xref: /freebsd/contrib/llvm-project/clang/lib/APINotes/APINotesManager.cpp (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1 //===--- APINotesManager.cpp - Manage API Notes Files ---------------------===//
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 #include "clang/APINotes/APINotesManager.h"
10 #include "clang/APINotes/APINotesReader.h"
11 #include "clang/APINotes/APINotesYAMLCompiler.h"
12 #include "clang/Basic/Diagnostic.h"
13 #include "clang/Basic/FileManager.h"
14 #include "clang/Basic/LangOptions.h"
15 #include "clang/Basic/SourceManager.h"
16 #include "clang/Basic/SourceMgrAdapter.h"
17 #include "clang/Basic/Version.h"
18 #include "llvm/ADT/APInt.h"
19 #include "llvm/ADT/Hashing.h"
20 #include "llvm/ADT/SetVector.h"
21 #include "llvm/ADT/SmallPtrSet.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/Statistic.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Support/Path.h"
26 #include "llvm/Support/PrettyStackTrace.h"
27 
28 using namespace clang;
29 using namespace api_notes;
30 
31 #define DEBUG_TYPE "API Notes"
32 STATISTIC(NumHeaderAPINotes, "non-framework API notes files loaded");
33 STATISTIC(NumPublicFrameworkAPINotes, "framework public API notes loaded");
34 STATISTIC(NumPrivateFrameworkAPINotes, "framework private API notes loaded");
35 STATISTIC(NumFrameworksSearched, "frameworks searched");
36 STATISTIC(NumDirectoriesSearched, "header directories searched");
37 STATISTIC(NumDirectoryCacheHits, "directory cache hits");
38 
39 namespace {
40 /// Prints two successive strings, which much be kept alive as long as the
41 /// PrettyStackTrace entry.
42 class PrettyStackTraceDoubleString : public llvm::PrettyStackTraceEntry {
43   StringRef First, Second;
44 
45 public:
46   PrettyStackTraceDoubleString(StringRef First, StringRef Second)
47       : First(First), Second(Second) {}
48   void print(raw_ostream &OS) const override { OS << First << Second; }
49 };
50 } // namespace
51 
52 APINotesManager::APINotesManager(SourceManager &SM, const LangOptions &LangOpts)
53     : SM(SM), ImplicitAPINotes(LangOpts.APINotes) {}
54 
55 APINotesManager::~APINotesManager() {
56   // Free the API notes readers.
57   for (const auto &Entry : Readers) {
58     if (auto Reader = Entry.second.dyn_cast<APINotesReader *>())
59       delete Reader;
60   }
61 
62   delete CurrentModuleReaders[ReaderKind::Public];
63   delete CurrentModuleReaders[ReaderKind::Private];
64 }
65 
66 std::unique_ptr<APINotesReader>
67 APINotesManager::loadAPINotes(FileEntryRef APINotesFile) {
68   PrettyStackTraceDoubleString Trace("Loading API notes from ",
69                                      APINotesFile.getName());
70 
71   // Open the source file.
72   auto SourceFileID = SM.getOrCreateFileID(APINotesFile, SrcMgr::C_User);
73   auto SourceBuffer = SM.getBufferOrNone(SourceFileID, SourceLocation());
74   if (!SourceBuffer)
75     return nullptr;
76 
77   // Compile the API notes source into a buffer.
78   // FIXME: Either propagate OSType through or, better yet, improve the binary
79   // APINotes format to maintain complete availability information.
80   // FIXME: We don't even really need to go through the binary format at all;
81   // we're just going to immediately deserialize it again.
82   llvm::SmallVector<char, 1024> APINotesBuffer;
83   std::unique_ptr<llvm::MemoryBuffer> CompiledBuffer;
84   {
85     SourceMgrAdapter SMAdapter(
86         SM, SM.getDiagnostics(), diag::err_apinotes_message,
87         diag::warn_apinotes_message, diag::note_apinotes_message, APINotesFile);
88     llvm::raw_svector_ostream OS(APINotesBuffer);
89     if (api_notes::compileAPINotes(
90             SourceBuffer->getBuffer(), SM.getFileEntryForID(SourceFileID), OS,
91             SMAdapter.getDiagHandler(), SMAdapter.getDiagContext()))
92       return nullptr;
93 
94     // Make a copy of the compiled form into the buffer.
95     CompiledBuffer = llvm::MemoryBuffer::getMemBufferCopy(
96         StringRef(APINotesBuffer.data(), APINotesBuffer.size()));
97   }
98 
99   // Load the binary form we just compiled.
100   auto Reader = APINotesReader::Create(std::move(CompiledBuffer), SwiftVersion);
101   assert(Reader && "Could not load the API notes we just generated?");
102   return Reader;
103 }
104 
105 std::unique_ptr<APINotesReader>
106 APINotesManager::loadAPINotes(StringRef Buffer) {
107   llvm::SmallVector<char, 1024> APINotesBuffer;
108   std::unique_ptr<llvm::MemoryBuffer> CompiledBuffer;
109   SourceMgrAdapter SMAdapter(
110       SM, SM.getDiagnostics(), diag::err_apinotes_message,
111       diag::warn_apinotes_message, diag::note_apinotes_message, std::nullopt);
112   llvm::raw_svector_ostream OS(APINotesBuffer);
113 
114   if (api_notes::compileAPINotes(Buffer, nullptr, OS,
115                                  SMAdapter.getDiagHandler(),
116                                  SMAdapter.getDiagContext()))
117     return nullptr;
118 
119   CompiledBuffer = llvm::MemoryBuffer::getMemBufferCopy(
120       StringRef(APINotesBuffer.data(), APINotesBuffer.size()));
121   auto Reader = APINotesReader::Create(std::move(CompiledBuffer), SwiftVersion);
122   assert(Reader && "Could not load the API notes we just generated?");
123   return Reader;
124 }
125 
126 bool APINotesManager::loadAPINotes(const DirectoryEntry *HeaderDir,
127                                    FileEntryRef APINotesFile) {
128   assert(!Readers.contains(HeaderDir));
129   if (auto Reader = loadAPINotes(APINotesFile)) {
130     Readers[HeaderDir] = Reader.release();
131     return false;
132   }
133 
134   Readers[HeaderDir] = nullptr;
135   return true;
136 }
137 
138 OptionalFileEntryRef
139 APINotesManager::findAPINotesFile(DirectoryEntryRef Directory,
140                                   StringRef Basename, bool WantPublic) {
141   FileManager &FM = SM.getFileManager();
142 
143   llvm::SmallString<128> Path(Directory.getName());
144 
145   StringRef Suffix = WantPublic ? "" : "_private";
146 
147   // Look for the source API notes file.
148   llvm::sys::path::append(Path, llvm::Twine(Basename) + Suffix + "." +
149                                     SOURCE_APINOTES_EXTENSION);
150   return FM.getOptionalFileRef(Path, /*Open*/ true);
151 }
152 
153 OptionalDirectoryEntryRef APINotesManager::loadFrameworkAPINotes(
154     llvm::StringRef FrameworkPath, llvm::StringRef FrameworkName, bool Public) {
155   FileManager &FM = SM.getFileManager();
156 
157   llvm::SmallString<128> Path(FrameworkPath);
158   unsigned FrameworkNameLength = Path.size();
159 
160   StringRef Suffix = Public ? "" : "_private";
161 
162   // Form the path to the APINotes file.
163   llvm::sys::path::append(Path, "APINotes");
164   llvm::sys::path::append(Path, (llvm::Twine(FrameworkName) + Suffix + "." +
165                                  SOURCE_APINOTES_EXTENSION));
166 
167   // Try to open the APINotes file.
168   auto APINotesFile = FM.getOptionalFileRef(Path);
169   if (!APINotesFile)
170     return std::nullopt;
171 
172   // Form the path to the corresponding header directory.
173   Path.resize(FrameworkNameLength);
174   llvm::sys::path::append(Path, Public ? "Headers" : "PrivateHeaders");
175 
176   // Try to access the header directory.
177   auto HeaderDir = FM.getOptionalDirectoryRef(Path);
178   if (!HeaderDir)
179     return std::nullopt;
180 
181   // Try to load the API notes.
182   if (loadAPINotes(*HeaderDir, *APINotesFile))
183     return std::nullopt;
184 
185   // Success: return the header directory.
186   if (Public)
187     ++NumPublicFrameworkAPINotes;
188   else
189     ++NumPrivateFrameworkAPINotes;
190   return *HeaderDir;
191 }
192 
193 static void checkPrivateAPINotesName(DiagnosticsEngine &Diags,
194                                      const FileEntry *File, const Module *M) {
195   if (File->tryGetRealPathName().empty())
196     return;
197 
198   StringRef RealFileName =
199       llvm::sys::path::filename(File->tryGetRealPathName());
200   StringRef RealStem = llvm::sys::path::stem(RealFileName);
201   if (RealStem.ends_with("_private"))
202     return;
203 
204   unsigned DiagID = diag::warn_apinotes_private_case;
205   if (M->IsSystem)
206     DiagID = diag::warn_apinotes_private_case_system;
207 
208   Diags.Report(SourceLocation(), DiagID) << M->Name << RealFileName;
209 }
210 
211 /// \returns true if any of \p module's immediate submodules are defined in a
212 /// private module map
213 static bool hasPrivateSubmodules(const Module *M) {
214   return llvm::any_of(M->submodules(), [](const Module *Submodule) {
215     return Submodule->ModuleMapIsPrivate;
216   });
217 }
218 
219 llvm::SmallVector<FileEntryRef, 2>
220 APINotesManager::getCurrentModuleAPINotes(Module *M, bool LookInModule,
221                                           ArrayRef<std::string> SearchPaths) {
222   FileManager &FM = SM.getFileManager();
223   auto ModuleName = M->getTopLevelModuleName();
224   llvm::SmallVector<FileEntryRef, 2> APINotes;
225 
226   // First, look relative to the module itself.
227   if (LookInModule) {
228     // Local function to try loading an API notes file in the given directory.
229     auto tryAPINotes = [&](DirectoryEntryRef Dir, bool WantPublic) {
230       if (auto File = findAPINotesFile(Dir, ModuleName, WantPublic)) {
231         if (!WantPublic)
232           checkPrivateAPINotesName(SM.getDiagnostics(), *File, M);
233 
234         APINotes.push_back(*File);
235       }
236     };
237 
238     if (M->IsFramework) {
239       // For frameworks, we search in the "Headers" or "PrivateHeaders"
240       // subdirectory.
241       //
242       // Public modules:
243       // - Headers/Foo.apinotes
244       // - PrivateHeaders/Foo_private.apinotes (if there are private submodules)
245       // Private modules:
246       // - PrivateHeaders/Bar.apinotes (except that 'Bar' probably already has
247       //   the word "Private" in it in practice)
248       llvm::SmallString<128> Path(M->Directory->getName());
249 
250       if (!M->ModuleMapIsPrivate) {
251         unsigned PathLen = Path.size();
252 
253         llvm::sys::path::append(Path, "Headers");
254         if (auto APINotesDir = FM.getOptionalDirectoryRef(Path))
255           tryAPINotes(*APINotesDir, /*wantPublic=*/true);
256 
257         Path.resize(PathLen);
258       }
259 
260       if (M->ModuleMapIsPrivate || hasPrivateSubmodules(M)) {
261         llvm::sys::path::append(Path, "PrivateHeaders");
262         if (auto PrivateAPINotesDir = FM.getOptionalDirectoryRef(Path))
263           tryAPINotes(*PrivateAPINotesDir,
264                       /*wantPublic=*/M->ModuleMapIsPrivate);
265       }
266     } else {
267       // Public modules:
268       // - Foo.apinotes
269       // - Foo_private.apinotes (if there are private submodules)
270       // Private modules:
271       // - Bar.apinotes (except that 'Bar' probably already has the word
272       //   "Private" in it in practice)
273       tryAPINotes(*M->Directory, /*wantPublic=*/true);
274       if (!M->ModuleMapIsPrivate && hasPrivateSubmodules(M))
275         tryAPINotes(*M->Directory, /*wantPublic=*/false);
276     }
277 
278     if (!APINotes.empty())
279       return APINotes;
280   }
281 
282   // Second, look for API notes for this module in the module API
283   // notes search paths.
284   for (const auto &SearchPath : SearchPaths) {
285     if (auto SearchDir = FM.getOptionalDirectoryRef(SearchPath)) {
286       if (auto File = findAPINotesFile(*SearchDir, ModuleName)) {
287         APINotes.push_back(*File);
288         return APINotes;
289       }
290     }
291   }
292 
293   // Didn't find any API notes.
294   return APINotes;
295 }
296 
297 bool APINotesManager::loadCurrentModuleAPINotes(
298     Module *M, bool LookInModule, ArrayRef<std::string> SearchPaths) {
299   assert(!CurrentModuleReaders[ReaderKind::Public] &&
300          "Already loaded API notes for the current module?");
301 
302   auto APINotes = getCurrentModuleAPINotes(M, LookInModule, SearchPaths);
303   unsigned NumReaders = 0;
304   for (auto File : APINotes) {
305     CurrentModuleReaders[NumReaders++] = loadAPINotes(File).release();
306     if (!getCurrentModuleReaders().empty())
307       M->APINotesFile = File.getName().str();
308   }
309 
310   return NumReaders > 0;
311 }
312 
313 bool APINotesManager::loadCurrentModuleAPINotesFromBuffer(
314     ArrayRef<StringRef> Buffers) {
315   unsigned NumReader = 0;
316   for (auto Buf : Buffers) {
317     auto Reader = loadAPINotes(Buf);
318     assert(Reader && "Could not load the API notes we just generated?");
319 
320     CurrentModuleReaders[NumReader++] = Reader.release();
321   }
322   return NumReader;
323 }
324 
325 llvm::SmallVector<APINotesReader *, 2>
326 APINotesManager::findAPINotes(SourceLocation Loc) {
327   llvm::SmallVector<APINotesReader *, 2> Results;
328 
329   // If there are readers for the current module, return them.
330   if (!getCurrentModuleReaders().empty()) {
331     Results.append(getCurrentModuleReaders().begin(),
332                    getCurrentModuleReaders().end());
333     return Results;
334   }
335 
336   // If we're not allowed to implicitly load API notes files, we're done.
337   if (!ImplicitAPINotes)
338     return Results;
339 
340   // If we don't have source location information, we're done.
341   if (Loc.isInvalid())
342     return Results;
343 
344   // API notes are associated with the expansion location. Retrieve the
345   // file for this location.
346   SourceLocation ExpansionLoc = SM.getExpansionLoc(Loc);
347   FileID ID = SM.getFileID(ExpansionLoc);
348   if (ID.isInvalid())
349     return Results;
350   OptionalFileEntryRef File = SM.getFileEntryRefForID(ID);
351   if (!File)
352     return Results;
353 
354   // Look for API notes in the directory corresponding to this file, or one of
355   // its its parent directories.
356   OptionalDirectoryEntryRef Dir = File->getDir();
357   FileManager &FileMgr = SM.getFileManager();
358   llvm::SetVector<const DirectoryEntry *,
359                   SmallVector<const DirectoryEntry *, 4>,
360                   llvm::SmallPtrSet<const DirectoryEntry *, 4>>
361       DirsVisited;
362   do {
363     // Look for an API notes reader for this header search directory.
364     auto Known = Readers.find(*Dir);
365 
366     // If we already know the answer, chase it.
367     if (Known != Readers.end()) {
368       ++NumDirectoryCacheHits;
369 
370       // We've been redirected to another directory for answers. Follow it.
371       if (Known->second && Known->second.is<DirectoryEntryRef>()) {
372         DirsVisited.insert(*Dir);
373         Dir = Known->second.get<DirectoryEntryRef>();
374         continue;
375       }
376 
377       // We have the answer.
378       if (auto Reader = Known->second.dyn_cast<APINotesReader *>())
379         Results.push_back(Reader);
380       break;
381     }
382 
383     // Look for API notes corresponding to this directory.
384     StringRef Path = Dir->getName();
385     if (llvm::sys::path::extension(Path) == ".framework") {
386       // If this is a framework directory, check whether there are API notes
387       // in the APINotes subdirectory.
388       auto FrameworkName = llvm::sys::path::stem(Path);
389       ++NumFrameworksSearched;
390 
391       // Look for API notes for both the public and private headers.
392       OptionalDirectoryEntryRef PublicDir =
393           loadFrameworkAPINotes(Path, FrameworkName, /*Public=*/true);
394       OptionalDirectoryEntryRef PrivateDir =
395           loadFrameworkAPINotes(Path, FrameworkName, /*Public=*/false);
396 
397       if (PublicDir || PrivateDir) {
398         // We found API notes: don't ever look past the framework directory.
399         Readers[*Dir] = nullptr;
400 
401         // Pretend we found the result in the public or private directory,
402         // as appropriate. All headers should be in one of those two places,
403         // but be defensive here.
404         if (!DirsVisited.empty()) {
405           if (PublicDir && DirsVisited.back() == *PublicDir) {
406             DirsVisited.pop_back();
407             Dir = *PublicDir;
408           } else if (PrivateDir && DirsVisited.back() == *PrivateDir) {
409             DirsVisited.pop_back();
410             Dir = *PrivateDir;
411           }
412         }
413 
414         // Grab the result.
415         if (auto Reader = Readers[*Dir].dyn_cast<APINotesReader *>())
416           Results.push_back(Reader);
417         break;
418       }
419     } else {
420       // Look for an APINotes file in this directory.
421       llvm::SmallString<128> APINotesPath(Dir->getName());
422       llvm::sys::path::append(
423           APINotesPath, (llvm::Twine("APINotes.") + SOURCE_APINOTES_EXTENSION));
424 
425       // If there is an API notes file here, try to load it.
426       ++NumDirectoriesSearched;
427       if (auto APINotesFile = FileMgr.getOptionalFileRef(APINotesPath)) {
428         if (!loadAPINotes(*Dir, *APINotesFile)) {
429           ++NumHeaderAPINotes;
430           if (auto Reader = Readers[*Dir].dyn_cast<APINotesReader *>())
431             Results.push_back(Reader);
432           break;
433         }
434       }
435     }
436 
437     // We didn't find anything. Look at the parent directory.
438     if (!DirsVisited.insert(*Dir)) {
439       Dir = std::nullopt;
440       break;
441     }
442 
443     StringRef ParentPath = llvm::sys::path::parent_path(Path);
444     while (llvm::sys::path::stem(ParentPath) == "..")
445       ParentPath = llvm::sys::path::parent_path(ParentPath);
446 
447     Dir = ParentPath.empty() ? std::nullopt
448                              : FileMgr.getOptionalDirectoryRef(ParentPath);
449   } while (Dir);
450 
451   // Path compression for all of the directories we visited, redirecting
452   // them to the directory we ended on. If no API notes were found, the
453   // resulting directory will be NULL, indicating no API notes.
454   for (const auto Visited : DirsVisited)
455     Readers[Visited] = Dir ? ReaderEntry(*Dir) : ReaderEntry();
456 
457   return Results;
458 }
459