1 //===-- CXLoadedDiagnostic.cpp - Handling of persisent diags ----*- C++ -*-===//
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 // Implements handling of persisent diagnostics.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CXLoadedDiagnostic.h"
14 #include "CXString.h"
15 #include "clang/Basic/Diagnostic.h"
16 #include "clang/Basic/FileManager.h"
17 #include "clang/Basic/LLVM.h"
18 #include "clang/Frontend/SerializedDiagnosticReader.h"
19 #include "clang/Frontend/SerializedDiagnostics.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/ADT/Twine.h"
23 #include "llvm/Bitstream/BitstreamReader.h"
24 #include "llvm/Support/ErrorHandling.h"
25 
26 using namespace clang;
27 
28 //===----------------------------------------------------------------------===//
29 // Extend CXDiagnosticSetImpl which contains strings for diagnostics.
30 //===----------------------------------------------------------------------===//
31 
32 typedef llvm::DenseMap<unsigned, const char *> Strings;
33 
34 namespace {
35 class CXLoadedDiagnosticSetImpl : public CXDiagnosticSetImpl {
36 public:
CXLoadedDiagnosticSetImpl()37   CXLoadedDiagnosticSetImpl() : CXDiagnosticSetImpl(true), FakeFiles(FO) {}
~CXLoadedDiagnosticSetImpl()38   ~CXLoadedDiagnosticSetImpl() override {}
39 
40   llvm::BumpPtrAllocator Alloc;
41   Strings Categories;
42   Strings WarningFlags;
43   Strings FileNames;
44 
45   FileSystemOptions FO;
46   FileManager FakeFiles;
47   llvm::DenseMap<unsigned, const FileEntry *> Files;
48 
49   /// Copy the string into our own allocator.
copyString(StringRef Blob)50   const char *copyString(StringRef Blob) {
51     char *mem = Alloc.Allocate<char>(Blob.size() + 1);
52     memcpy(mem, Blob.data(), Blob.size());
53     mem[Blob.size()] = '\0';
54     return mem;
55   }
56 };
57 } // end anonymous namespace
58 
59 //===----------------------------------------------------------------------===//
60 // Cleanup.
61 //===----------------------------------------------------------------------===//
62 
~CXLoadedDiagnostic()63 CXLoadedDiagnostic::~CXLoadedDiagnostic() {}
64 
65 //===----------------------------------------------------------------------===//
66 // Public CXLoadedDiagnostic methods.
67 //===----------------------------------------------------------------------===//
68 
getSeverity() const69 CXDiagnosticSeverity CXLoadedDiagnostic::getSeverity() const {
70   // FIXME: Fail more softly if the diagnostic level is unknown?
71   auto severityAsLevel = static_cast<serialized_diags::Level>(severity);
72   assert(severity == static_cast<unsigned>(severityAsLevel) &&
73          "unknown serialized diagnostic level");
74 
75   switch (severityAsLevel) {
76 #define CASE(X) case serialized_diags::X: return CXDiagnostic_##X;
77   CASE(Ignored)
78   CASE(Note)
79   CASE(Warning)
80   CASE(Error)
81   CASE(Fatal)
82 #undef CASE
83   // The 'Remark' level isn't represented in the stable API.
84   case serialized_diags::Remark: return CXDiagnostic_Warning;
85   }
86 
87   llvm_unreachable("Invalid diagnostic level");
88 }
89 
makeLocation(const CXLoadedDiagnostic::Location * DLoc)90 static CXSourceLocation makeLocation(const CXLoadedDiagnostic::Location *DLoc) {
91   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
92   // is a persistent diagnostic.
93   uintptr_t V = (uintptr_t) DLoc;
94   V |= 0x1;
95   CXSourceLocation Loc = { {  (void*) V, nullptr }, 0 };
96   return Loc;
97 }
98 
getLocation() const99 CXSourceLocation CXLoadedDiagnostic::getLocation() const {
100   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
101   // is a persistent diagnostic.
102   return makeLocation(&DiagLoc);
103 }
104 
getSpelling() const105 CXString CXLoadedDiagnostic::getSpelling() const {
106   return cxstring::createRef(Spelling);
107 }
108 
getDiagnosticOption(CXString * Disable) const109 CXString CXLoadedDiagnostic::getDiagnosticOption(CXString *Disable) const {
110   if (DiagOption.empty())
111     return cxstring::createEmpty();
112 
113   // FIXME: possibly refactor with logic in CXStoredDiagnostic.
114   if (Disable)
115     *Disable = cxstring::createDup((Twine("-Wno-") + DiagOption).str());
116   return cxstring::createDup((Twine("-W") + DiagOption).str());
117 }
118 
getCategory() const119 unsigned CXLoadedDiagnostic::getCategory() const {
120   return category;
121 }
122 
getCategoryText() const123 CXString CXLoadedDiagnostic::getCategoryText() const {
124   return cxstring::createDup(CategoryText);
125 }
126 
getNumRanges() const127 unsigned CXLoadedDiagnostic::getNumRanges() const {
128   return Ranges.size();
129 }
130 
getRange(unsigned Range) const131 CXSourceRange CXLoadedDiagnostic::getRange(unsigned Range) const {
132   assert(Range < Ranges.size());
133   return Ranges[Range];
134 }
135 
getNumFixIts() const136 unsigned CXLoadedDiagnostic::getNumFixIts() const {
137   return FixIts.size();
138 }
139 
getFixIt(unsigned FixIt,CXSourceRange * ReplacementRange) const140 CXString CXLoadedDiagnostic::getFixIt(unsigned FixIt,
141                                       CXSourceRange *ReplacementRange) const {
142   assert(FixIt < FixIts.size());
143   if (ReplacementRange)
144     *ReplacementRange = FixIts[FixIt].first;
145   return cxstring::createRef(FixIts[FixIt].second);
146 }
147 
decodeLocation(CXSourceLocation location,CXFile * file,unsigned int * line,unsigned int * column,unsigned int * offset)148 void CXLoadedDiagnostic::decodeLocation(CXSourceLocation location,
149                                         CXFile *file,
150                                         unsigned int *line,
151                                         unsigned int *column,
152                                         unsigned int *offset) {
153 
154 
155   // CXSourceLocation consists of the following fields:
156   //
157   //   void *ptr_data[2];
158   //   unsigned int_data;
159   //
160   // The lowest bit of ptr_data[0] is always set to 1 to indicate this
161   // is a persistent diagnostic.
162   //
163   // For now, do the unoptimized approach and store the data in a side
164   // data structure.  We can optimize this case later.
165 
166   uintptr_t V = (uintptr_t) location.ptr_data[0];
167   assert((V & 0x1) == 1);
168   V &= ~(uintptr_t)1;
169 
170   const Location &Loc = *((Location*)V);
171 
172   if (file)
173     *file = Loc.file;
174   if (line)
175     *line = Loc.line;
176   if (column)
177     *column = Loc.column;
178   if (offset)
179     *offset = Loc.offset;
180 }
181 
182 //===----------------------------------------------------------------------===//
183 // Deserialize diagnostics.
184 //===----------------------------------------------------------------------===//
185 
186 namespace {
187 class DiagLoader : serialized_diags::SerializedDiagnosticReader {
188   enum CXLoadDiag_Error *error;
189   CXString *errorString;
190   std::unique_ptr<CXLoadedDiagnosticSetImpl> TopDiags;
191   SmallVector<std::unique_ptr<CXLoadedDiagnostic>, 8> CurrentDiags;
192 
reportBad(enum CXLoadDiag_Error code,llvm::StringRef err)193   std::error_code reportBad(enum CXLoadDiag_Error code, llvm::StringRef err) {
194     if (error)
195       *error = code;
196     if (errorString)
197       *errorString = cxstring::createDup(err);
198     return serialized_diags::SDError::HandlerFailed;
199   }
200 
reportInvalidFile(llvm::StringRef err)201   std::error_code reportInvalidFile(llvm::StringRef err) {
202     return reportBad(CXLoadDiag_InvalidFile, err);
203   }
204 
205   std::error_code readRange(const serialized_diags::Location &SDStart,
206                             const serialized_diags::Location &SDEnd,
207                             CXSourceRange &SR);
208 
209   std::error_code readLocation(const serialized_diags::Location &SDLoc,
210                                CXLoadedDiagnostic::Location &LoadedLoc);
211 
212 protected:
213   std::error_code visitStartOfDiagnostic() override;
214   std::error_code visitEndOfDiagnostic() override;
215 
216   std::error_code visitCategoryRecord(unsigned ID, StringRef Name) override;
217 
218   std::error_code visitDiagFlagRecord(unsigned ID, StringRef Name) override;
219 
220   std::error_code visitDiagnosticRecord(
221       unsigned Severity, const serialized_diags::Location &Location,
222       unsigned Category, unsigned Flag, StringRef Message) override;
223 
224   std::error_code visitFilenameRecord(unsigned ID, unsigned Size,
225                                       unsigned Timestamp,
226                                       StringRef Name) override;
227 
228   std::error_code visitFixitRecord(const serialized_diags::Location &Start,
229                                    const serialized_diags::Location &End,
230                                    StringRef CodeToInsert) override;
231 
232   std::error_code
233   visitSourceRangeRecord(const serialized_diags::Location &Start,
234                          const serialized_diags::Location &End) override;
235 
236 public:
DiagLoader(enum CXLoadDiag_Error * e,CXString * es)237   DiagLoader(enum CXLoadDiag_Error *e, CXString *es)
238       : SerializedDiagnosticReader(), error(e), errorString(es) {
239     if (error)
240       *error = CXLoadDiag_None;
241     if (errorString)
242       *errorString = cxstring::createEmpty();
243   }
244 
245   CXDiagnosticSet load(const char *file);
246 };
247 } // end anonymous namespace
248 
load(const char * file)249 CXDiagnosticSet DiagLoader::load(const char *file) {
250   TopDiags = std::make_unique<CXLoadedDiagnosticSetImpl>();
251 
252   std::error_code EC = readDiagnostics(file);
253   if (EC) {
254     switch (EC.value()) {
255     case static_cast<int>(serialized_diags::SDError::HandlerFailed):
256       // We've already reported the problem.
257       break;
258     case static_cast<int>(serialized_diags::SDError::CouldNotLoad):
259       reportBad(CXLoadDiag_CannotLoad, EC.message());
260       break;
261     default:
262       reportInvalidFile(EC.message());
263       break;
264     }
265     return nullptr;
266   }
267 
268   return (CXDiagnosticSet)TopDiags.release();
269 }
270 
271 std::error_code
readLocation(const serialized_diags::Location & SDLoc,CXLoadedDiagnostic::Location & LoadedLoc)272 DiagLoader::readLocation(const serialized_diags::Location &SDLoc,
273                          CXLoadedDiagnostic::Location &LoadedLoc) {
274   unsigned FileID = SDLoc.FileID;
275   if (FileID == 0)
276     LoadedLoc.file = nullptr;
277   else {
278     LoadedLoc.file = const_cast<FileEntry *>(TopDiags->Files[FileID]);
279     if (!LoadedLoc.file)
280       return reportInvalidFile("Corrupted file entry in source location");
281   }
282   LoadedLoc.line = SDLoc.Line;
283   LoadedLoc.column = SDLoc.Col;
284   LoadedLoc.offset = SDLoc.Offset;
285   return std::error_code();
286 }
287 
288 std::error_code
readRange(const serialized_diags::Location & SDStart,const serialized_diags::Location & SDEnd,CXSourceRange & SR)289 DiagLoader::readRange(const serialized_diags::Location &SDStart,
290                       const serialized_diags::Location &SDEnd,
291                       CXSourceRange &SR) {
292   CXLoadedDiagnostic::Location *Start, *End;
293   Start = TopDiags->Alloc.Allocate<CXLoadedDiagnostic::Location>();
294   End = TopDiags->Alloc.Allocate<CXLoadedDiagnostic::Location>();
295 
296   std::error_code EC;
297   if ((EC = readLocation(SDStart, *Start)))
298     return EC;
299   if ((EC = readLocation(SDEnd, *End)))
300     return EC;
301 
302   CXSourceLocation startLoc = makeLocation(Start);
303   CXSourceLocation endLoc = makeLocation(End);
304   SR = clang_getRange(startLoc, endLoc);
305   return std::error_code();
306 }
307 
visitStartOfDiagnostic()308 std::error_code DiagLoader::visitStartOfDiagnostic() {
309   CurrentDiags.push_back(std::make_unique<CXLoadedDiagnostic>());
310   return std::error_code();
311 }
312 
visitEndOfDiagnostic()313 std::error_code DiagLoader::visitEndOfDiagnostic() {
314   auto D = CurrentDiags.pop_back_val();
315   if (CurrentDiags.empty())
316     TopDiags->appendDiagnostic(std::move(D));
317   else
318     CurrentDiags.back()->getChildDiagnostics().appendDiagnostic(std::move(D));
319   return std::error_code();
320 }
321 
visitCategoryRecord(unsigned ID,StringRef Name)322 std::error_code DiagLoader::visitCategoryRecord(unsigned ID, StringRef Name) {
323   // FIXME: Why do we care about long strings?
324   if (Name.size() > 65536)
325     return reportInvalidFile("Out-of-bounds string in category");
326   TopDiags->Categories[ID] = TopDiags->copyString(Name);
327   return std::error_code();
328 }
329 
visitDiagFlagRecord(unsigned ID,StringRef Name)330 std::error_code DiagLoader::visitDiagFlagRecord(unsigned ID, StringRef Name) {
331   // FIXME: Why do we care about long strings?
332   if (Name.size() > 65536)
333     return reportInvalidFile("Out-of-bounds string in warning flag");
334   TopDiags->WarningFlags[ID] = TopDiags->copyString(Name);
335   return std::error_code();
336 }
337 
visitFilenameRecord(unsigned ID,unsigned Size,unsigned Timestamp,StringRef Name)338 std::error_code DiagLoader::visitFilenameRecord(unsigned ID, unsigned Size,
339                                                 unsigned Timestamp,
340                                                 StringRef Name) {
341   // FIXME: Why do we care about long strings?
342   if (Name.size() > 65536)
343     return reportInvalidFile("Out-of-bounds string in filename");
344   TopDiags->FileNames[ID] = TopDiags->copyString(Name);
345   TopDiags->Files[ID] =
346       TopDiags->FakeFiles.getVirtualFile(Name, Size, Timestamp);
347   return std::error_code();
348 }
349 
350 std::error_code
visitSourceRangeRecord(const serialized_diags::Location & Start,const serialized_diags::Location & End)351 DiagLoader::visitSourceRangeRecord(const serialized_diags::Location &Start,
352                                    const serialized_diags::Location &End) {
353   CXSourceRange SR;
354   if (std::error_code EC = readRange(Start, End, SR))
355     return EC;
356   CurrentDiags.back()->Ranges.push_back(SR);
357   return std::error_code();
358 }
359 
360 std::error_code
visitFixitRecord(const serialized_diags::Location & Start,const serialized_diags::Location & End,StringRef CodeToInsert)361 DiagLoader::visitFixitRecord(const serialized_diags::Location &Start,
362                              const serialized_diags::Location &End,
363                              StringRef CodeToInsert) {
364   CXSourceRange SR;
365   if (std::error_code EC = readRange(Start, End, SR))
366     return EC;
367   // FIXME: Why do we care about long strings?
368   if (CodeToInsert.size() > 65536)
369     return reportInvalidFile("Out-of-bounds string in FIXIT");
370   CurrentDiags.back()->FixIts.push_back(
371       std::make_pair(SR, TopDiags->copyString(CodeToInsert)));
372   return std::error_code();
373 }
374 
visitDiagnosticRecord(unsigned Severity,const serialized_diags::Location & Location,unsigned Category,unsigned Flag,StringRef Message)375 std::error_code DiagLoader::visitDiagnosticRecord(
376     unsigned Severity, const serialized_diags::Location &Location,
377     unsigned Category, unsigned Flag, StringRef Message) {
378   CXLoadedDiagnostic &D = *CurrentDiags.back();
379   D.severity = Severity;
380   if (std::error_code EC = readLocation(Location, D.DiagLoc))
381     return EC;
382   D.category = Category;
383   D.DiagOption = Flag ? TopDiags->WarningFlags[Flag] : "";
384   D.CategoryText = Category ? TopDiags->Categories[Category] : "";
385   D.Spelling = TopDiags->copyString(Message);
386   return std::error_code();
387 }
388 
clang_loadDiagnostics(const char * file,enum CXLoadDiag_Error * error,CXString * errorString)389 CXDiagnosticSet clang_loadDiagnostics(const char *file,
390                                       enum CXLoadDiag_Error *error,
391                                       CXString *errorString) {
392   DiagLoader L(error, errorString);
393   return L.load(file);
394 }
395