src/llvm/lib/Support/SourceMgr.cpp

   1 //===- SourceMgr.cpp - Manager for Simple Source Buffers & Diagnostics ----===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the SourceMgr class.  This class is used as a simple
  11 // substrate for diagnostics, #include handling, and other low level things for
  12 // simple parsers.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "llvm/Support/SourceMgr.h"
  17 #include "llvm/ADT/SmallString.h"
  18 #include "llvm/ADT/Twine.h"
  19 #include "llvm/Support/Locale.h"
  20 #include "llvm/Support/MemoryBuffer.h"
  21 #include "llvm/Support/Path.h"
  22 #include "llvm/Support/raw_ostream.h"
  23 #include <system_error>
  24 using namespace llvm;
  25
  26 static const size_t TabStop = 8;
  27
  28 namespace {
  29   struct LineNoCacheTy {
  30     unsigned LastQueryBufferID;
  31     const char *LastQuery;
  32     unsigned LineNoOfQuery;
  33   };
  34 }
  35
  36 static LineNoCacheTy *getCache(void *Ptr) {
  37   return (LineNoCacheTy*)Ptr;
  38 }
  39
  40
  41 SourceMgr::~SourceMgr() {
  42   // Delete the line # cache if allocated.
  43   if (LineNoCacheTy *Cache = getCache(LineNoCache))
  44     delete Cache;
  45 }
  46
  47 unsigned SourceMgr::AddIncludeFile(const std::string &Filename,
  48                                    SMLoc IncludeLoc,
  49                                    std::string &IncludedFile) {
  50   IncludedFile = Filename;
  51   ErrorOr<std::unique_ptr<MemoryBuffer>> NewBufOrErr =
  52     MemoryBuffer::getFile(IncludedFile);
  53
  54   // If the file didn't exist directly, see if it's in an include path.
  55   for (unsigned i = 0, e = IncludeDirectories.size(); i != e && !NewBufOrErr;
  56        ++i) {
  57     IncludedFile =
  58         IncludeDirectories[i] + sys::path::get_separator().data() + Filename;
  59     NewBufOrErr = MemoryBuffer::getFile(IncludedFile);
  60   }
  61
  62   if (!NewBufOrErr)
  63     return 0;
  64
  65   return AddNewSourceBuffer(std::move(*NewBufOrErr), IncludeLoc);
  66 }
  67
  68 unsigned SourceMgr::FindBufferContainingLoc(SMLoc Loc) const {
  69   for (unsigned i = 0, e = Buffers.size(); i != e; ++i)
  70     if (Loc.getPointer() >= Buffers[i].Buffer->getBufferStart() &&
  71         // Use <= here so that a pointer to the null at the end of the buffer
  72         // is included as part of the buffer.
  73         Loc.getPointer() <= Buffers[i].Buffer->getBufferEnd())
  74       return i + 1;
  75   return 0;
  76 }
  77
  78 std::pair<unsigned, unsigned>
  79 SourceMgr::getLineAndColumn(SMLoc Loc, unsigned BufferID) const {
  80   if (!BufferID)
  81     BufferID = FindBufferContainingLoc(Loc);
  82   assert(BufferID && "Invalid Location!");
  83
  84   const MemoryBuffer *Buff = getMemoryBuffer(BufferID);
  85
  86   // Count the number of \n's between the start of the file and the specified
  87   // location.
  88   unsigned LineNo = 1;
  89
  90   const char *BufStart = Buff->getBufferStart();
  91   const char *Ptr = BufStart;
  92
  93   // If we have a line number cache, and if the query is to a later point in the
  94   // same file, start searching from the last query location.  This optimizes
  95   // for the case when multiple diagnostics come out of one file in order.
  96   if (LineNoCacheTy *Cache = getCache(LineNoCache))
  97     if (Cache->LastQueryBufferID == BufferID &&
  98         Cache->LastQuery <= Loc.getPointer()) {
  99       Ptr = Cache->LastQuery;
 100       LineNo = Cache->LineNoOfQuery;
 101     }
 102
 103   // Scan for the location being queried, keeping track of the number of lines
 104   // we see.
 105   for (; SMLoc::getFromPointer(Ptr) != Loc; ++Ptr)
 106     if (*Ptr == '\n') ++LineNo;
 107
 108   // Allocate the line number cache if it doesn't exist.
 109   if (!LineNoCache)
 110     LineNoCache = new LineNoCacheTy();
 111
 112   // Update the line # cache.
 113   LineNoCacheTy &Cache = *getCache(LineNoCache);
 114   Cache.LastQueryBufferID = BufferID;
 115   Cache.LastQuery = Ptr;
 116   Cache.LineNoOfQuery = LineNo;
 117
 118   size_t NewlineOffs = StringRef(BufStart, Ptr-BufStart).find_last_of("\n\r");
 119   if (NewlineOffs == StringRef::npos) NewlineOffs = ~(size_t)0;
 120   return std::make_pair(LineNo, Ptr-BufStart-NewlineOffs);
 121 }
 122
 123 void SourceMgr::PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const {
 124   if (IncludeLoc == SMLoc()) return;  // Top of stack.
 125
 126   unsigned CurBuf = FindBufferContainingLoc(IncludeLoc);
 127   assert(CurBuf && "Invalid or unspecified location!");
 128
 129   PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
 130
 131   OS << "Included from "
 132      << getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
 133      << ":" << FindLineNumber(IncludeLoc, CurBuf) << ":\n";
 134 }
 135
 136
 137 SMDiagnostic SourceMgr::GetMessage(SMLoc Loc, SourceMgr::DiagKind Kind,
 138                                    const Twine &Msg,
 139                                    ArrayRef<SMRange> Ranges,
 140                                    ArrayRef<SMFixIt> FixIts) const {
 141
 142   // First thing to do: find the current buffer containing the specified
 143   // location to pull out the source line.
 144   SmallVector<std::pair<unsigned, unsigned>, 4> ColRanges;
 145   std::pair<unsigned, unsigned> LineAndCol;
 146   const char *BufferID = "<unknown>";
 147   std::string LineStr;
 148
 149   if (Loc.isValid()) {
 150     unsigned CurBuf = FindBufferContainingLoc(Loc);
 151     assert(CurBuf && "Invalid or unspecified location!");
 152
 153     const MemoryBuffer *CurMB = getMemoryBuffer(CurBuf);
 154     BufferID = CurMB->getBufferIdentifier();
 155
 156     // Scan backward to find the start of the line.
 157     const char *LineStart = Loc.getPointer();
 158     const char *BufStart = CurMB->getBufferStart();
 159     while (LineStart != BufStart && LineStart[-1] != '\n' &&
 160            LineStart[-1] != '\r')
 161       --LineStart;
 162
 163     // Get the end of the line.
 164     const char *LineEnd = Loc.getPointer();
 165     const char *BufEnd = CurMB->getBufferEnd();
 166     while (LineEnd != BufEnd && LineEnd[0] != '\n' && LineEnd[0] != '\r')
 167       ++LineEnd;
 168     LineStr = std::string(LineStart, LineEnd);
 169
 170     // Convert any ranges to column ranges that only intersect the line of the
 171     // location.
 172     for (unsigned i = 0, e = Ranges.size(); i != e; ++i) {
 173       SMRange R = Ranges[i];
 174       if (!R.isValid()) continue;
 175
 176       // If the line doesn't contain any part of the range, then ignore it.
 177       if (R.Start.getPointer() > LineEnd || R.End.getPointer() < LineStart)
 178         continue;
 179
 180       // Ignore pieces of the range that go onto other lines.
 181       if (R.Start.getPointer() < LineStart)
 182         R.Start = SMLoc::getFromPointer(LineStart);
 183       if (R.End.getPointer() > LineEnd)
 184         R.End = SMLoc::getFromPointer(LineEnd);
 185
 186       // Translate from SMLoc ranges to column ranges.
 187       // FIXME: Handle multibyte characters.
 188       ColRanges.push_back(std::make_pair(R.Start.getPointer()-LineStart,
 189                                          R.End.getPointer()-LineStart));
 190     }
 191
 192     LineAndCol = getLineAndColumn(Loc, CurBuf);
 193   }
 194
 195   return SMDiagnostic(*this, Loc, BufferID, LineAndCol.first,
 196                       LineAndCol.second-1, Kind, Msg.str(),
 197                       LineStr, ColRanges, FixIts);
 198 }
 199
 200 void SourceMgr::PrintMessage(raw_ostream &OS, const SMDiagnostic &Diagnostic,
 201                              bool ShowColors) const {
 202   // Report the message with the diagnostic handler if present.
 203   if (DiagHandler) {
 204     DiagHandler(Diagnostic, DiagContext);
 205     return;
 206   }
 207
 208   if (Diagnostic.getLoc().isValid()) {
 209     unsigned CurBuf = FindBufferContainingLoc(Diagnostic.getLoc());
 210     assert(CurBuf && "Invalid or unspecified location!");
 211     PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
 212   }
 213
 214   Diagnostic.print(nullptr, OS, ShowColors);
 215 }
 216
 217 void SourceMgr::PrintMessage(raw_ostream &OS, SMLoc Loc,
 218                              SourceMgr::DiagKind Kind,
 219                              const Twine &Msg, ArrayRef<SMRange> Ranges,
 220                              ArrayRef<SMFixIt> FixIts, bool ShowColors) const {
 221   PrintMessage(OS, GetMessage(Loc, Kind, Msg, Ranges, FixIts), ShowColors);
 222 }
 223
 224 void SourceMgr::PrintMessage(SMLoc Loc, SourceMgr::DiagKind Kind,
 225                              const Twine &Msg, ArrayRef<SMRange> Ranges,
 226                              ArrayRef<SMFixIt> FixIts, bool ShowColors) const {
 227   PrintMessage(llvm::errs(), Loc, Kind, Msg, Ranges, FixIts, ShowColors);
 228 }
 229
 230 //===----------------------------------------------------------------------===//
 231 // SMDiagnostic Implementation
 232 //===----------------------------------------------------------------------===//
 233
 234 SMDiagnostic::SMDiagnostic(const SourceMgr &sm, SMLoc L, StringRef FN,
 235                            int Line, int Col, SourceMgr::DiagKind Kind,
 236                            StringRef Msg, StringRef LineStr,
 237                            ArrayRef<std::pair<unsigned,unsigned> > Ranges,
 238                            ArrayRef<SMFixIt> Hints)
 239   : SM(&sm), Loc(L), Filename(FN), LineNo(Line), ColumnNo(Col), Kind(Kind),
 240     Message(Msg), LineContents(LineStr), Ranges(Ranges.vec()),
 241     FixIts(Hints.begin(), Hints.end()) {
 242   std::sort(FixIts.begin(), FixIts.end());
 243 }
 244
 245 static void buildFixItLine(std::string &CaretLine, std::string &FixItLine,
 246                            ArrayRef<SMFixIt> FixIts, ArrayRef<char> SourceLine){
 247   if (FixIts.empty())
 248     return;
 249
 250   const char *LineStart = SourceLine.begin();
 251   const char *LineEnd = SourceLine.end();
 252
 253   size_t PrevHintEndCol = 0;
 254
 255   for (ArrayRef<SMFixIt>::iterator I = FixIts.begin(), E = FixIts.end();
 256        I != E; ++I) {
 257     // If the fixit contains a newline or tab, ignore it.
 258     if (I->getText().find_first_of("\n\r\t") != StringRef::npos)
 259       continue;
 260
 261     SMRange R = I->getRange();
 262
 263     // If the line doesn't contain any part of the range, then ignore it.
 264     if (R.Start.getPointer() > LineEnd || R.End.getPointer() < LineStart)
 265       continue;
 266
 267     // Translate from SMLoc to column.
 268     // Ignore pieces of the range that go onto other lines.
 269     // FIXME: Handle multibyte characters in the source line.
 270     unsigned FirstCol;
 271     if (R.Start.getPointer() < LineStart)
 272       FirstCol = 0;
 273     else
 274       FirstCol = R.Start.getPointer() - LineStart;
 275
 276     // If we inserted a long previous hint, push this one forwards, and add
 277     // an extra space to show that this is not part of the previous
 278     // completion. This is sort of the best we can do when two hints appear
 279     // to overlap.
 280     //
 281     // Note that if this hint is located immediately after the previous
 282     // hint, no space will be added, since the location is more important.
 283     unsigned HintCol = FirstCol;
 284     if (HintCol < PrevHintEndCol)
 285       HintCol = PrevHintEndCol + 1;
 286
 287     // FIXME: This assertion is intended to catch unintended use of multibyte
 288     // characters in fixits. If we decide to do this, we'll have to track
 289     // separate byte widths for the source and fixit lines.
 290     assert((size_t)llvm::sys::locale::columnWidth(I->getText()) ==
 291            I->getText().size());
 292
 293     // This relies on one byte per column in our fixit hints.
 294     unsigned LastColumnModified = HintCol + I->getText().size();
 295     if (LastColumnModified > FixItLine.size())
 296       FixItLine.resize(LastColumnModified, ' ');
 297
 298     std::copy(I->getText().begin(), I->getText().end(),
 299               FixItLine.begin() + HintCol);
 300
 301     PrevHintEndCol = LastColumnModified;
 302
 303     // For replacements, mark the removal range with '~'.
 304     // FIXME: Handle multibyte characters in the source line.
 305     unsigned LastCol;
 306     if (R.End.getPointer() >= LineEnd)
 307       LastCol = LineEnd - LineStart;
 308     else
 309       LastCol = R.End.getPointer() - LineStart;
 310
 311     std::fill(&CaretLine[FirstCol], &CaretLine[LastCol], '~');
 312   }
 313 }
 314
 315 static void printSourceLine(raw_ostream &S, StringRef LineContents) {
 316   // Print out the source line one character at a time, so we can expand tabs.
 317   for (unsigned i = 0, e = LineContents.size(), OutCol = 0; i != e; ++i) {
 318     if (LineContents[i] != '\t') {
 319       S << LineContents[i];
 320       ++OutCol;
 321       continue;
 322     }
 323
 324     // If we have a tab, emit at least one space, then round up to 8 columns.
 325     do {
 326       S << ' ';
 327       ++OutCol;
 328     } while ((OutCol % TabStop) != 0);
 329   }
 330   S << '\n';
 331 }
 332
 333 static bool isNonASCII(char c) {
 334   return c & 0x80;
 335 }
 336
 337 void SMDiagnostic::print(const char *ProgName, raw_ostream &S,
 338                          bool ShowColors) const {
 339   // Display colors only if OS supports colors.
 340   ShowColors &= S.has_colors();
 341
 342   if (ShowColors)
 343     S.changeColor(raw_ostream::SAVEDCOLOR, true);
 344
 345   if (ProgName && ProgName[0])
 346     S << ProgName << ": ";
 347
 348   if (!Filename.empty()) {
 349     if (Filename == "-")
 350       S << "<stdin>";
 351     else
 352       S << Filename;
 353
 354     if (LineNo != -1) {
 355       S << ':' << LineNo;
 356       if (ColumnNo != -1)
 357         S << ':' << (ColumnNo+1);
 358     }
 359     S << ": ";
 360   }
 361
 362   switch (Kind) {
 363   case SourceMgr::DK_Error:
 364     if (ShowColors)
 365       S.changeColor(raw_ostream::RED, true);
 366     S << "error: ";
 367     break;
 368   case SourceMgr::DK_Warning:
 369     if (ShowColors)
 370       S.changeColor(raw_ostream::MAGENTA, true);
 371     S << "warning: ";
 372     break;
 373   case SourceMgr::DK_Note:
 374     if (ShowColors)
 375       S.changeColor(raw_ostream::BLACK, true);
 376     S << "note: ";
 377     break;
 378   }
 379
 380   if (ShowColors) {
 381     S.resetColor();
 382     S.changeColor(raw_ostream::SAVEDCOLOR, true);
 383   }
 384
 385   S << Message << '\n';
 386
 387   if (ShowColors)
 388     S.resetColor();
 389
 390   if (LineNo == -1 || ColumnNo == -1)
 391     return;
 392
 393   // FIXME: If there are multibyte or multi-column characters in the source, all
 394   // our ranges will be wrong. To do this properly, we'll need a byte-to-column
 395   // map like Clang's TextDiagnostic. For now, we'll just handle tabs by
 396   // expanding them later, and bail out rather than show incorrect ranges and
 397   // misaligned fixits for any other odd characters.
 398   if (std::find_if(LineContents.begin(), LineContents.end(), isNonASCII) !=
 399       LineContents.end()) {
 400     printSourceLine(S, LineContents);
 401     return;
 402   }
 403   size_t NumColumns = LineContents.size();
 404
 405   // Build the line with the caret and ranges.
 406   std::string CaretLine(NumColumns+1, ' ');
 407
 408   // Expand any ranges.
 409   for (unsigned r = 0, e = Ranges.size(); r != e; ++r) {
 410     std::pair<unsigned, unsigned> R = Ranges[r];
 411     std::fill(&CaretLine[R.first],
 412               &CaretLine[std::min((size_t)R.second, CaretLine.size())],
 413               '~');
 414   }
 415
 416   // Add any fix-its.
 417   // FIXME: Find the beginning of the line properly for multibyte characters.
 418   std::string FixItInsertionLine;
 419   buildFixItLine(CaretLine, FixItInsertionLine, FixIts,
 420                  makeArrayRef(Loc.getPointer() - ColumnNo,
 421                               LineContents.size()));
 422
 423   // Finally, plop on the caret.
 424   if (unsigned(ColumnNo) <= NumColumns)
 425     CaretLine[ColumnNo] = '^';
 426   else
 427     CaretLine[NumColumns] = '^';
 428
 429   // ... and remove trailing whitespace so the output doesn't wrap for it.  We
 430   // know that the line isn't completely empty because it has the caret in it at
 431   // least.
 432   CaretLine.erase(CaretLine.find_last_not_of(' ')+1);
 433
 434   printSourceLine(S, LineContents);
 435
 436   if (ShowColors)
 437     S.changeColor(raw_ostream::GREEN, true);
 438
 439   // Print out the caret line, matching tabs in the source line.
 440   for (unsigned i = 0, e = CaretLine.size(), OutCol = 0; i != e; ++i) {
 441     if (i >= LineContents.size() || LineContents[i] != '\t') {
 442       S << CaretLine[i];
 443       ++OutCol;
 444       continue;
 445     }
 446
 447     // Okay, we have a tab.  Insert the appropriate number of characters.
 448     do {
 449       S << CaretLine[i];
 450       ++OutCol;
 451     } while ((OutCol % TabStop) != 0);
 452   }
 453   S << '\n';
 454
 455   if (ShowColors)
 456     S.resetColor();
 457
 458   // Print out the replacement line, matching tabs in the source line.
 459   if (FixItInsertionLine.empty())
 460     return;
 461
 462   for (size_t i = 0, e = FixItInsertionLine.size(), OutCol = 0; i < e; ++i) {
 463     if (i >= LineContents.size() || LineContents[i] != '\t') {
 464       S << FixItInsertionLine[i];
 465       ++OutCol;
 466       continue;
 467     }
 468
 469     // Okay, we have a tab.  Insert the appropriate number of characters.
 470     do {
 471       S << FixItInsertionLine[i];
 472       // FIXME: This is trying not to break up replacements, but then to re-sync
 473       // with the tabs between replacements. This will fail, though, if two
 474       // fix-it replacements are exactly adjacent, or if a fix-it contains a
 475       // space. Really we should be precomputing column widths, which we'll
 476       // need anyway for multibyte chars.
 477       if (FixItInsertionLine[i] != ' ')
 478         ++i;
 479       ++OutCol;
 480     } while (((OutCol % TabStop) != 0) && i != e);
 481   }
 482   S << '\n';
 483 }