1 //===-- CXLoadedDiagnostic.cpp - Handling of persisent diags ----*- C++ -*-===//
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 // Implements handling of persisent diagnostics.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CXLoadedDiagnostic.h"
15 #include "CXString.h"
16 #include "clang/Basic/Diagnostic.h"
17 #include "clang/Basic/FileManager.h"
18 #include "clang/Basic/LLVM.h"
19 #include "clang/Frontend/SerializedDiagnosticReader.h"
20 #include "clang/Frontend/SerializedDiagnostics.h"
21 #include "llvm/ADT/Optional.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/ADT/Twine.h"
25 #include "llvm/Bitcode/BitstreamReader.h"
26 #include "llvm/Support/ErrorHandling.h"
27 #include "llvm/Support/MemoryBuffer.h"
28 using namespace clang;
29 
30 //===----------------------------------------------------------------------===//
31 // Extend CXDiagnosticSetImpl which contains strings for diagnostics.
32 //===----------------------------------------------------------------------===//
33 
34 typedef llvm::DenseMap<unsigned, const char *> Strings;
35 
36 namespace {
37 class CXLoadedDiagnosticSetImpl : public CXDiagnosticSetImpl {
38 public:
CXLoadedDiagnosticSetImpl()39   CXLoadedDiagnosticSetImpl() : CXDiagnosticSetImpl(true), FakeFiles(FO) {}
~CXLoadedDiagnosticSetImpl()40   ~CXLoadedDiagnosticSetImpl() override {}
41 
42   llvm::BumpPtrAllocator Alloc;
43   Strings Categories;
44   Strings WarningFlags;
45   Strings FileNames;
46 
47   FileSystemOptions FO;
48   FileManager FakeFiles;
49   llvm::DenseMap<unsigned, const FileEntry *> Files;
50 
51   /// \brief Copy the string into our own allocator.
copyString(StringRef Blob)52   const char *copyString(StringRef Blob) {
53     char *mem = Alloc.Allocate<char>(Blob.size() + 1);
54     memcpy(mem, Blob.data(), Blob.size());
55     mem[Blob.size()] = '\0';
56     return mem;
57   }
58 };
59 }
60 
61 //===----------------------------------------------------------------------===//
62 // Cleanup.
63 //===----------------------------------------------------------------------===//
64 
~CXLoadedDiagnostic()65 CXLoadedDiagnostic::~CXLoadedDiagnostic() {}
66 
67 //===----------------------------------------------------------------------===//
68 // Public CXLoadedDiagnostic methods.
69 //===----------------------------------------------------------------------===//
70 
getSeverity() const71 CXDiagnosticSeverity CXLoadedDiagnostic::getSeverity() const {
72   // FIXME: Fail more softly if the diagnostic level is unknown?
73   auto severityAsLevel = static_cast<serialized_diags::Level>(severity);
74   assert(severity == static_cast<unsigned>(severityAsLevel) &&
75          "unknown serialized diagnostic level");
76 
77   switch (severityAsLevel) {
78 #define CASE(X) case serialized_diags::X: return CXDiagnostic_##X;
79   CASE(Ignored)
80   CASE(Note)
81   CASE(Warning)
82   CASE(Error)
83   CASE(Fatal)
84 #undef CASE
85   // The 'Remark' level isn't represented in the stable API.
86   case serialized_diags::Remark: return CXDiagnostic_Warning;
87   }
88 
89   llvm_unreachable("Invalid diagnostic level");
90 }
91 
makeLocation(const CXLoadedDiagnostic::Location * DLoc)92 static CXSourceLocation makeLocation(const CXLoadedDiagnostic::Location *DLoc) {
93   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
94   // is a persistent diagnostic.
95   uintptr_t V = (uintptr_t) DLoc;
96   V |= 0x1;
97   CXSourceLocation Loc = { {  (void*) V, nullptr }, 0 };
98   return Loc;
99 }
100 
getLocation() const101 CXSourceLocation CXLoadedDiagnostic::getLocation() const {
102   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
103   // is a persistent diagnostic.
104   return makeLocation(&DiagLoc);
105 }
106 
getSpelling() const107 CXString CXLoadedDiagnostic::getSpelling() const {
108   return cxstring::createRef(Spelling);
109 }
110 
getDiagnosticOption(CXString * Disable) const111 CXString CXLoadedDiagnostic::getDiagnosticOption(CXString *Disable) const {
112   if (DiagOption.empty())
113     return cxstring::createEmpty();
114 
115   // FIXME: possibly refactor with logic in CXStoredDiagnostic.
116   if (Disable)
117     *Disable = cxstring::createDup((Twine("-Wno-") + DiagOption).str());
118   return cxstring::createDup((Twine("-W") + DiagOption).str());
119 }
120 
getCategory() const121 unsigned CXLoadedDiagnostic::getCategory() const {
122   return category;
123 }
124 
getCategoryText() const125 CXString CXLoadedDiagnostic::getCategoryText() const {
126   return cxstring::createDup(CategoryText);
127 }
128 
getNumRanges() const129 unsigned CXLoadedDiagnostic::getNumRanges() const {
130   return Ranges.size();
131 }
132 
getRange(unsigned Range) const133 CXSourceRange CXLoadedDiagnostic::getRange(unsigned Range) const {
134   assert(Range < Ranges.size());
135   return Ranges[Range];
136 }
137 
getNumFixIts() const138 unsigned CXLoadedDiagnostic::getNumFixIts() const {
139   return FixIts.size();
140 }
141 
getFixIt(unsigned FixIt,CXSourceRange * ReplacementRange) const142 CXString CXLoadedDiagnostic::getFixIt(unsigned FixIt,
143                                       CXSourceRange *ReplacementRange) const {
144   assert(FixIt < FixIts.size());
145   if (ReplacementRange)
146     *ReplacementRange = FixIts[FixIt].first;
147   return cxstring::createRef(FixIts[FixIt].second);
148 }
149 
decodeLocation(CXSourceLocation location,CXFile * file,unsigned int * line,unsigned int * column,unsigned int * offset)150 void CXLoadedDiagnostic::decodeLocation(CXSourceLocation location,
151                                         CXFile *file,
152                                         unsigned int *line,
153                                         unsigned int *column,
154                                         unsigned int *offset) {
155 
156 
157   // CXSourceLocation consists of the following fields:
158   //
159   //   void *ptr_data[2];
160   //   unsigned int_data;
161   //
162   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
163   // is a persistent diagnostic.
164   //
165   // For now, do the unoptimized approach and store the data in a side
166   // data structure.  We can optimize this case later.
167 
168   uintptr_t V = (uintptr_t) location.ptr_data[0];
169   assert((V & 0x1) == 1);
170   V &= ~(uintptr_t)1;
171 
172   const Location &Loc = *((Location*)V);
173 
174   if (file)
175     *file = Loc.file;
176   if (line)
177     *line = Loc.line;
178   if (column)
179     *column = Loc.column;
180   if (offset)
181     *offset = Loc.offset;
182 }
183 
184 //===----------------------------------------------------------------------===//
185 // Deserialize diagnostics.
186 //===----------------------------------------------------------------------===//
187 
188 namespace {
189 class DiagLoader : serialized_diags::SerializedDiagnosticReader {
190   enum CXLoadDiag_Error *error;
191   CXString *errorString;
192   std::unique_ptr<CXLoadedDiagnosticSetImpl> TopDiags;
193   SmallVector<std::unique_ptr<CXLoadedDiagnostic>, 8> CurrentDiags;
194 
reportBad(enum CXLoadDiag_Error code,llvm::StringRef err)195   std::error_code reportBad(enum CXLoadDiag_Error code, llvm::StringRef err) {
196     if (error)
197       *error = code;
198     if (errorString)
199       *errorString = cxstring::createDup(err);
200     return serialized_diags::SDError::HandlerFailed;
201   }
202 
reportInvalidFile(llvm::StringRef err)203   std::error_code reportInvalidFile(llvm::StringRef err) {
204     return reportBad(CXLoadDiag_InvalidFile, err);
205   }
206 
207   std::error_code readRange(const serialized_diags::Location &SDStart,
208                             const serialized_diags::Location &SDEnd,
209                             CXSourceRange &SR);
210 
211   std::error_code readLocation(const serialized_diags::Location &SDLoc,
212                                CXLoadedDiagnostic::Location &LoadedLoc);
213 
214 protected:
215   std::error_code visitStartOfDiagnostic() override;
216   std::error_code visitEndOfDiagnostic() override;
217 
218   std::error_code visitCategoryRecord(unsigned ID, StringRef Name) override;
219 
220   std::error_code visitDiagFlagRecord(unsigned ID, StringRef Name) override;
221 
222   std::error_code visitDiagnosticRecord(
223       unsigned Severity, const serialized_diags::Location &Location,
224       unsigned Category, unsigned Flag, StringRef Message) override;
225 
226   std::error_code visitFilenameRecord(unsigned ID, unsigned Size,
227                                       unsigned Timestamp,
228                                       StringRef Name) override;
229 
230   std::error_code visitFixitRecord(const serialized_diags::Location &Start,
231                                    const serialized_diags::Location &End,
232                                    StringRef CodeToInsert) override;
233 
234   std::error_code
235   visitSourceRangeRecord(const serialized_diags::Location &Start,
236                          const serialized_diags::Location &End) override;
237 
238 public:
DiagLoader(enum CXLoadDiag_Error * e,CXString * es)239   DiagLoader(enum CXLoadDiag_Error *e, CXString *es)
240       : SerializedDiagnosticReader(), error(e), errorString(es) {
241     if (error)
242       *error = CXLoadDiag_None;
243     if (errorString)
244       *errorString = cxstring::createEmpty();
245   }
246 
247   CXDiagnosticSet load(const char *file);
248 };
249 }
250 
load(const char * file)251 CXDiagnosticSet DiagLoader::load(const char *file) {
252   TopDiags = llvm::make_unique<CXLoadedDiagnosticSetImpl>();
253 
254   std::error_code EC = readDiagnostics(file);
255   if (EC) {
256     switch (EC.value()) {
257     case static_cast<int>(serialized_diags::SDError::HandlerFailed):
258       // We've already reported the problem.
259       break;
260     case static_cast<int>(serialized_diags::SDError::CouldNotLoad):
261       reportBad(CXLoadDiag_CannotLoad, EC.message());
262       break;
263     default:
264       reportInvalidFile(EC.message());
265       break;
266     }
267     return 0;
268   }
269 
270   return (CXDiagnosticSet)TopDiags.release();
271 }
272 
273 std::error_code
readLocation(const serialized_diags::Location & SDLoc,CXLoadedDiagnostic::Location & LoadedLoc)274 DiagLoader::readLocation(const serialized_diags::Location &SDLoc,
275                          CXLoadedDiagnostic::Location &LoadedLoc) {
276   unsigned FileID = SDLoc.FileID;
277   if (FileID == 0)
278     LoadedLoc.file = nullptr;
279   else {
280     LoadedLoc.file = const_cast<FileEntry *>(TopDiags->Files[FileID]);
281     if (!LoadedLoc.file)
282       return reportInvalidFile("Corrupted file entry in source location");
283   }
284   LoadedLoc.line = SDLoc.Line;
285   LoadedLoc.column = SDLoc.Col;
286   LoadedLoc.offset = SDLoc.Offset;
287   return std::error_code();
288 }
289 
290 std::error_code
readRange(const serialized_diags::Location & SDStart,const serialized_diags::Location & SDEnd,CXSourceRange & SR)291 DiagLoader::readRange(const serialized_diags::Location &SDStart,
292                       const serialized_diags::Location &SDEnd,
293                       CXSourceRange &SR) {
294   CXLoadedDiagnostic::Location *Start, *End;
295   Start = TopDiags->Alloc.Allocate<CXLoadedDiagnostic::Location>();
296   End = TopDiags->Alloc.Allocate<CXLoadedDiagnostic::Location>();
297 
298   std::error_code EC;
299   if ((EC = readLocation(SDStart, *Start)))
300     return EC;
301   if ((EC = readLocation(SDEnd, *End)))
302     return EC;
303 
304   CXSourceLocation startLoc = makeLocation(Start);
305   CXSourceLocation endLoc = makeLocation(End);
306   SR = clang_getRange(startLoc, endLoc);
307   return std::error_code();
308 }
309 
visitStartOfDiagnostic()310 std::error_code DiagLoader::visitStartOfDiagnostic() {
311   CurrentDiags.push_back(llvm::make_unique<CXLoadedDiagnostic>());
312   return std::error_code();
313 }
314 
visitEndOfDiagnostic()315 std::error_code DiagLoader::visitEndOfDiagnostic() {
316   auto D = CurrentDiags.pop_back_val();
317   if (CurrentDiags.empty())
318     TopDiags->appendDiagnostic(std::move(D));
319   else
320     CurrentDiags.back()->getChildDiagnostics().appendDiagnostic(std::move(D));
321   return std::error_code();
322 }
323 
visitCategoryRecord(unsigned ID,StringRef Name)324 std::error_code DiagLoader::visitCategoryRecord(unsigned ID, StringRef Name) {
325   // FIXME: Why do we care about long strings?
326   if (Name.size() > 65536)
327     return reportInvalidFile("Out-of-bounds string in category");
328   TopDiags->Categories[ID] = TopDiags->copyString(Name);
329   return std::error_code();
330 }
331 
visitDiagFlagRecord(unsigned ID,StringRef Name)332 std::error_code DiagLoader::visitDiagFlagRecord(unsigned ID, StringRef Name) {
333   // FIXME: Why do we care about long strings?
334   if (Name.size() > 65536)
335     return reportInvalidFile("Out-of-bounds string in warning flag");
336   TopDiags->WarningFlags[ID] = TopDiags->copyString(Name);
337   return std::error_code();
338 }
339 
visitFilenameRecord(unsigned ID,unsigned Size,unsigned Timestamp,StringRef Name)340 std::error_code DiagLoader::visitFilenameRecord(unsigned ID, unsigned Size,
341                                                 unsigned Timestamp,
342                                                 StringRef Name) {
343   // FIXME: Why do we care about long strings?
344   if (Name.size() > 65536)
345     return reportInvalidFile("Out-of-bounds string in filename");
346   TopDiags->FileNames[ID] = TopDiags->copyString(Name);
347   TopDiags->Files[ID] =
348       TopDiags->FakeFiles.getVirtualFile(Name, Size, Timestamp);
349   return std::error_code();
350 }
351 
352 std::error_code
visitSourceRangeRecord(const serialized_diags::Location & Start,const serialized_diags::Location & End)353 DiagLoader::visitSourceRangeRecord(const serialized_diags::Location &Start,
354                                    const serialized_diags::Location &End) {
355   CXSourceRange SR;
356   if (std::error_code EC = readRange(Start, End, SR))
357     return EC;
358   CurrentDiags.back()->Ranges.push_back(SR);
359   return std::error_code();
360 }
361 
362 std::error_code
visitFixitRecord(const serialized_diags::Location & Start,const serialized_diags::Location & End,StringRef CodeToInsert)363 DiagLoader::visitFixitRecord(const serialized_diags::Location &Start,
364                              const serialized_diags::Location &End,
365                              StringRef CodeToInsert) {
366   CXSourceRange SR;
367   if (std::error_code EC = readRange(Start, End, SR))
368     return EC;
369   // FIXME: Why do we care about long strings?
370   if (CodeToInsert.size() > 65536)
371     return reportInvalidFile("Out-of-bounds string in FIXIT");
372   CurrentDiags.back()->FixIts.push_back(
373       std::make_pair(SR, TopDiags->copyString(CodeToInsert)));
374   return std::error_code();
375 }
376 
visitDiagnosticRecord(unsigned Severity,const serialized_diags::Location & Location,unsigned Category,unsigned Flag,StringRef Message)377 std::error_code DiagLoader::visitDiagnosticRecord(
378     unsigned Severity, const serialized_diags::Location &Location,
379     unsigned Category, unsigned Flag, StringRef Message) {
380   CXLoadedDiagnostic &D = *CurrentDiags.back();
381   D.severity = Severity;
382   if (std::error_code EC = readLocation(Location, D.DiagLoc))
383     return EC;
384   D.category = Category;
385   D.DiagOption = Flag ? TopDiags->WarningFlags[Flag] : "";
386   D.CategoryText = Category ? TopDiags->Categories[Category] : "";
387   D.Spelling = TopDiags->copyString(Message);
388   return std::error_code();
389 }
390 
391 extern "C" {
clang_loadDiagnostics(const char * file,enum CXLoadDiag_Error * error,CXString * errorString)392 CXDiagnosticSet clang_loadDiagnostics(const char *file,
393                                       enum CXLoadDiag_Error *error,
394                                       CXString *errorString) {
395   DiagLoader L(error, errorString);
396   return L.load(file);
397 }
398 } // end extern 'C'.
399