HeaderSearch.cpp revision 223017
1//===--- HeaderSearch.cpp - Resolve Header File Locations ---===// 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 DirectoryLookup and HeaderSearch interfaces. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Lex/HeaderSearch.h" 15#include "clang/Lex/HeaderMap.h" 16#include "clang/Basic/FileManager.h" 17#include "clang/Basic/IdentifierTable.h" 18#include "llvm/Support/FileSystem.h" 19#include "llvm/Support/Path.h" 20#include "llvm/ADT/SmallString.h" 21#include <cstdio> 22using namespace clang; 23 24const IdentifierInfo * 25HeaderFileInfo::getControllingMacro(ExternalIdentifierLookup *External) { 26 if (ControllingMacro) 27 return ControllingMacro; 28 29 if (!ControllingMacroID || !External) 30 return 0; 31 32 ControllingMacro = External->GetIdentifier(ControllingMacroID); 33 return ControllingMacro; 34} 35 36ExternalHeaderFileInfoSource::~ExternalHeaderFileInfoSource() {} 37 38HeaderSearch::HeaderSearch(FileManager &FM) 39 : FileMgr(FM), FrameworkMap(64) { 40 AngledDirIdx = 0; 41 SystemDirIdx = 0; 42 NoCurDirSearch = false; 43 44 ExternalLookup = 0; 45 ExternalSource = 0; 46 NumIncluded = 0; 47 NumMultiIncludeFileOptzn = 0; 48 NumFrameworkLookups = NumSubFrameworkLookups = 0; 49} 50 51HeaderSearch::~HeaderSearch() { 52 // Delete headermaps. 53 for (unsigned i = 0, e = HeaderMaps.size(); i != e; ++i) 54 delete HeaderMaps[i].second; 55} 56 57void HeaderSearch::PrintStats() { 58 fprintf(stderr, "\n*** HeaderSearch Stats:\n"); 59 fprintf(stderr, "%d files tracked.\n", (int)FileInfo.size()); 60 unsigned NumOnceOnlyFiles = 0, MaxNumIncludes = 0, NumSingleIncludedFiles = 0; 61 for (unsigned i = 0, e = FileInfo.size(); i != e; ++i) { 62 NumOnceOnlyFiles += FileInfo[i].isImport; 63 if (MaxNumIncludes < FileInfo[i].NumIncludes) 64 MaxNumIncludes = FileInfo[i].NumIncludes; 65 NumSingleIncludedFiles += FileInfo[i].NumIncludes == 1; 66 } 67 fprintf(stderr, " %d #import/#pragma once files.\n", NumOnceOnlyFiles); 68 fprintf(stderr, " %d included exactly once.\n", NumSingleIncludedFiles); 69 fprintf(stderr, " %d max times a file is included.\n", MaxNumIncludes); 70 71 fprintf(stderr, " %d #include/#include_next/#import.\n", NumIncluded); 72 fprintf(stderr, " %d #includes skipped due to" 73 " the multi-include optimization.\n", NumMultiIncludeFileOptzn); 74 75 fprintf(stderr, "%d framework lookups.\n", NumFrameworkLookups); 76 fprintf(stderr, "%d subframework lookups.\n", NumSubFrameworkLookups); 77} 78 79/// CreateHeaderMap - This method returns a HeaderMap for the specified 80/// FileEntry, uniquing them through the the 'HeaderMaps' datastructure. 81const HeaderMap *HeaderSearch::CreateHeaderMap(const FileEntry *FE) { 82 // We expect the number of headermaps to be small, and almost always empty. 83 // If it ever grows, use of a linear search should be re-evaluated. 84 if (!HeaderMaps.empty()) { 85 for (unsigned i = 0, e = HeaderMaps.size(); i != e; ++i) 86 // Pointer equality comparison of FileEntries works because they are 87 // already uniqued by inode. 88 if (HeaderMaps[i].first == FE) 89 return HeaderMaps[i].second; 90 } 91 92 if (const HeaderMap *HM = HeaderMap::Create(FE, FileMgr)) { 93 HeaderMaps.push_back(std::make_pair(FE, HM)); 94 return HM; 95 } 96 97 return 0; 98} 99 100//===----------------------------------------------------------------------===// 101// File lookup within a DirectoryLookup scope 102//===----------------------------------------------------------------------===// 103 104/// getName - Return the directory or filename corresponding to this lookup 105/// object. 106const char *DirectoryLookup::getName() const { 107 if (isNormalDir()) 108 return getDir()->getName(); 109 if (isFramework()) 110 return getFrameworkDir()->getName(); 111 assert(isHeaderMap() && "Unknown DirectoryLookup"); 112 return getHeaderMap()->getFileName(); 113} 114 115 116/// LookupFile - Lookup the specified file in this search path, returning it 117/// if it exists or returning null if not. 118const FileEntry *DirectoryLookup::LookupFile( 119 llvm::StringRef Filename, 120 HeaderSearch &HS, 121 llvm::SmallVectorImpl<char> *SearchPath, 122 llvm::SmallVectorImpl<char> *RelativePath) const { 123 llvm::SmallString<1024> TmpDir; 124 if (isNormalDir()) { 125 // Concatenate the requested file onto the directory. 126 // FIXME: Portability. Filename concatenation should be in sys::Path. 127 TmpDir += getDir()->getName(); 128 TmpDir.push_back('/'); 129 TmpDir.append(Filename.begin(), Filename.end()); 130 if (SearchPath != NULL) { 131 llvm::StringRef SearchPathRef(getDir()->getName()); 132 SearchPath->clear(); 133 SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); 134 } 135 if (RelativePath != NULL) { 136 RelativePath->clear(); 137 RelativePath->append(Filename.begin(), Filename.end()); 138 } 139 return HS.getFileMgr().getFile(TmpDir.str(), /*openFile=*/true); 140 } 141 142 if (isFramework()) 143 return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath); 144 145 assert(isHeaderMap() && "Unknown directory lookup"); 146 const FileEntry * const Result = getHeaderMap()->LookupFile( 147 Filename, HS.getFileMgr()); 148 if (Result) { 149 if (SearchPath != NULL) { 150 llvm::StringRef SearchPathRef(getName()); 151 SearchPath->clear(); 152 SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); 153 } 154 if (RelativePath != NULL) { 155 RelativePath->clear(); 156 RelativePath->append(Filename.begin(), Filename.end()); 157 } 158 } 159 return Result; 160} 161 162 163/// DoFrameworkLookup - Do a lookup of the specified file in the current 164/// DirectoryLookup, which is a framework directory. 165const FileEntry *DirectoryLookup::DoFrameworkLookup( 166 llvm::StringRef Filename, 167 HeaderSearch &HS, 168 llvm::SmallVectorImpl<char> *SearchPath, 169 llvm::SmallVectorImpl<char> *RelativePath) const { 170 FileManager &FileMgr = HS.getFileMgr(); 171 172 // Framework names must have a '/' in the filename. 173 size_t SlashPos = Filename.find('/'); 174 if (SlashPos == llvm::StringRef::npos) return 0; 175 176 // Find out if this is the home for the specified framework, by checking 177 // HeaderSearch. Possible answer are yes/no and unknown. 178 const DirectoryEntry *&FrameworkDirCache = 179 HS.LookupFrameworkCache(Filename.substr(0, SlashPos)); 180 181 // If it is known and in some other directory, fail. 182 if (FrameworkDirCache && FrameworkDirCache != getFrameworkDir()) 183 return 0; 184 185 // Otherwise, construct the path to this framework dir. 186 187 // FrameworkName = "/System/Library/Frameworks/" 188 llvm::SmallString<1024> FrameworkName; 189 FrameworkName += getFrameworkDir()->getName(); 190 if (FrameworkName.empty() || FrameworkName.back() != '/') 191 FrameworkName.push_back('/'); 192 193 // FrameworkName = "/System/Library/Frameworks/Cocoa" 194 FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos); 195 196 // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/" 197 FrameworkName += ".framework/"; 198 199 // If the cache entry is still unresolved, query to see if the cache entry is 200 // still unresolved. If so, check its existence now. 201 if (FrameworkDirCache == 0) { 202 HS.IncrementFrameworkLookupCount(); 203 204 // If the framework dir doesn't exist, we fail. 205 // FIXME: It's probably more efficient to query this with FileMgr.getDir. 206 bool Exists; 207 if (llvm::sys::fs::exists(FrameworkName.str(), Exists) || !Exists) 208 return 0; 209 210 // Otherwise, if it does, remember that this is the right direntry for this 211 // framework. 212 FrameworkDirCache = getFrameworkDir(); 213 } 214 215 if (RelativePath != NULL) { 216 RelativePath->clear(); 217 RelativePath->append(Filename.begin()+SlashPos+1, Filename.end()); 218 } 219 220 // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h" 221 unsigned OrigSize = FrameworkName.size(); 222 223 FrameworkName += "Headers/"; 224 225 if (SearchPath != NULL) { 226 SearchPath->clear(); 227 // Without trailing '/'. 228 SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1); 229 } 230 231 FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end()); 232 if (const FileEntry *FE = FileMgr.getFile(FrameworkName.str(), 233 /*openFile=*/true)) { 234 return FE; 235 } 236 237 // Check "/System/Library/Frameworks/Cocoa.framework/PrivateHeaders/file.h" 238 const char *Private = "Private"; 239 FrameworkName.insert(FrameworkName.begin()+OrigSize, Private, 240 Private+strlen(Private)); 241 if (SearchPath != NULL) 242 SearchPath->insert(SearchPath->begin()+OrigSize, Private, 243 Private+strlen(Private)); 244 245 return FileMgr.getFile(FrameworkName.str(), /*openFile=*/true); 246} 247 248 249//===----------------------------------------------------------------------===// 250// Header File Location. 251//===----------------------------------------------------------------------===// 252 253 254/// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 255/// return null on failure. isAngled indicates whether the file reference is 256/// for system #include's or not (i.e. using <> instead of ""). CurFileEnt, if 257/// non-null, indicates where the #including file is, in case a relative search 258/// is needed. 259const FileEntry *HeaderSearch::LookupFile( 260 llvm::StringRef Filename, 261 bool isAngled, 262 const DirectoryLookup *FromDir, 263 const DirectoryLookup *&CurDir, 264 const FileEntry *CurFileEnt, 265 llvm::SmallVectorImpl<char> *SearchPath, 266 llvm::SmallVectorImpl<char> *RelativePath) { 267 // If 'Filename' is absolute, check to see if it exists and no searching. 268 if (llvm::sys::path::is_absolute(Filename)) { 269 CurDir = 0; 270 271 // If this was an #include_next "/absolute/file", fail. 272 if (FromDir) return 0; 273 274 if (SearchPath != NULL) 275 SearchPath->clear(); 276 if (RelativePath != NULL) { 277 RelativePath->clear(); 278 RelativePath->append(Filename.begin(), Filename.end()); 279 } 280 // Otherwise, just return the file. 281 return FileMgr.getFile(Filename, /*openFile=*/true); 282 } 283 284 // Step #0, unless disabled, check to see if the file is in the #includer's 285 // directory. This has to be based on CurFileEnt, not CurDir, because 286 // CurFileEnt could be a #include of a subdirectory (#include "foo/bar.h") and 287 // a subsequent include of "baz.h" should resolve to "whatever/foo/baz.h". 288 // This search is not done for <> headers. 289 if (CurFileEnt && !isAngled && !NoCurDirSearch) { 290 llvm::SmallString<1024> TmpDir; 291 // Concatenate the requested file onto the directory. 292 // FIXME: Portability. Filename concatenation should be in sys::Path. 293 TmpDir += CurFileEnt->getDir()->getName(); 294 TmpDir.push_back('/'); 295 TmpDir.append(Filename.begin(), Filename.end()); 296 if (const FileEntry *FE = FileMgr.getFile(TmpDir.str(),/*openFile=*/true)) { 297 // Leave CurDir unset. 298 // This file is a system header or C++ unfriendly if the old file is. 299 // 300 // Note that the temporary 'DirInfo' is required here, as either call to 301 // getFileInfo could resize the vector and we don't want to rely on order 302 // of evaluation. 303 unsigned DirInfo = getFileInfo(CurFileEnt).DirInfo; 304 getFileInfo(FE).DirInfo = DirInfo; 305 if (SearchPath != NULL) { 306 llvm::StringRef SearchPathRef(CurFileEnt->getDir()->getName()); 307 SearchPath->clear(); 308 SearchPath->append(SearchPathRef.begin(), SearchPathRef.end()); 309 } 310 if (RelativePath != NULL) { 311 RelativePath->clear(); 312 RelativePath->append(Filename.begin(), Filename.end()); 313 } 314 return FE; 315 } 316 } 317 318 CurDir = 0; 319 320 // If this is a system #include, ignore the user #include locs. 321 unsigned i = isAngled ? AngledDirIdx : 0; 322 323 // If this is a #include_next request, start searching after the directory the 324 // file was found in. 325 if (FromDir) 326 i = FromDir-&SearchDirs[0]; 327 328 // Cache all of the lookups performed by this method. Many headers are 329 // multiply included, and the "pragma once" optimization prevents them from 330 // being relex/pp'd, but they would still have to search through a 331 // (potentially huge) series of SearchDirs to find it. 332 std::pair<unsigned, unsigned> &CacheLookup = 333 LookupFileCache.GetOrCreateValue(Filename).getValue(); 334 335 // If the entry has been previously looked up, the first value will be 336 // non-zero. If the value is equal to i (the start point of our search), then 337 // this is a matching hit. 338 if (CacheLookup.first == i+1) { 339 // Skip querying potentially lots of directories for this lookup. 340 i = CacheLookup.second; 341 } else { 342 // Otherwise, this is the first query, or the previous query didn't match 343 // our search start. We will fill in our found location below, so prime the 344 // start point value. 345 CacheLookup.first = i+1; 346 } 347 348 // Check each directory in sequence to see if it contains this file. 349 for (; i != SearchDirs.size(); ++i) { 350 const FileEntry *FE = 351 SearchDirs[i].LookupFile(Filename, *this, SearchPath, RelativePath); 352 if (!FE) continue; 353 354 CurDir = &SearchDirs[i]; 355 356 // This file is a system header or C++ unfriendly if the dir is. 357 getFileInfo(FE).DirInfo = CurDir->getDirCharacteristic(); 358 359 // Remember this location for the next lookup we do. 360 CacheLookup.second = i; 361 return FE; 362 } 363 364 // Otherwise, didn't find it. Remember we didn't find this. 365 CacheLookup.second = SearchDirs.size(); 366 return 0; 367} 368 369/// LookupSubframeworkHeader - Look up a subframework for the specified 370/// #include file. For example, if #include'ing <HIToolbox/HIToolbox.h> from 371/// within ".../Carbon.framework/Headers/Carbon.h", check to see if HIToolbox 372/// is a subframework within Carbon.framework. If so, return the FileEntry 373/// for the designated file, otherwise return null. 374const FileEntry *HeaderSearch:: 375LookupSubframeworkHeader(llvm::StringRef Filename, 376 const FileEntry *ContextFileEnt, 377 llvm::SmallVectorImpl<char> *SearchPath, 378 llvm::SmallVectorImpl<char> *RelativePath) { 379 assert(ContextFileEnt && "No context file?"); 380 381 // Framework names must have a '/' in the filename. Find it. 382 size_t SlashPos = Filename.find('/'); 383 if (SlashPos == llvm::StringRef::npos) return 0; 384 385 // Look up the base framework name of the ContextFileEnt. 386 const char *ContextName = ContextFileEnt->getName(); 387 388 // If the context info wasn't a framework, couldn't be a subframework. 389 const char *FrameworkPos = strstr(ContextName, ".framework/"); 390 if (FrameworkPos == 0) 391 return 0; 392 393 llvm::SmallString<1024> FrameworkName(ContextName, 394 FrameworkPos+strlen(".framework/")); 395 396 // Append Frameworks/HIToolbox.framework/ 397 FrameworkName += "Frameworks/"; 398 FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos); 399 FrameworkName += ".framework/"; 400 401 llvm::StringMapEntry<const DirectoryEntry *> &CacheLookup = 402 FrameworkMap.GetOrCreateValue(Filename.substr(0, SlashPos)); 403 404 // Some other location? 405 if (CacheLookup.getValue() && 406 CacheLookup.getKeyLength() == FrameworkName.size() && 407 memcmp(CacheLookup.getKeyData(), &FrameworkName[0], 408 CacheLookup.getKeyLength()) != 0) 409 return 0; 410 411 // Cache subframework. 412 if (CacheLookup.getValue() == 0) { 413 ++NumSubFrameworkLookups; 414 415 // If the framework dir doesn't exist, we fail. 416 const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.str()); 417 if (Dir == 0) return 0; 418 419 // Otherwise, if it does, remember that this is the right direntry for this 420 // framework. 421 CacheLookup.setValue(Dir); 422 } 423 424 const FileEntry *FE = 0; 425 426 if (RelativePath != NULL) { 427 RelativePath->clear(); 428 RelativePath->append(Filename.begin()+SlashPos+1, Filename.end()); 429 } 430 431 // Check ".../Frameworks/HIToolbox.framework/Headers/HIToolbox.h" 432 llvm::SmallString<1024> HeadersFilename(FrameworkName); 433 HeadersFilename += "Headers/"; 434 if (SearchPath != NULL) { 435 SearchPath->clear(); 436 // Without trailing '/'. 437 SearchPath->append(HeadersFilename.begin(), HeadersFilename.end()-1); 438 } 439 440 HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end()); 441 if (!(FE = FileMgr.getFile(HeadersFilename.str(), /*openFile=*/true))) { 442 443 // Check ".../Frameworks/HIToolbox.framework/PrivateHeaders/HIToolbox.h" 444 HeadersFilename = FrameworkName; 445 HeadersFilename += "PrivateHeaders/"; 446 if (SearchPath != NULL) { 447 SearchPath->clear(); 448 // Without trailing '/'. 449 SearchPath->append(HeadersFilename.begin(), HeadersFilename.end()-1); 450 } 451 452 HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end()); 453 if (!(FE = FileMgr.getFile(HeadersFilename.str(), /*openFile=*/true))) 454 return 0; 455 } 456 457 // This file is a system header or C++ unfriendly if the old file is. 458 // 459 // Note that the temporary 'DirInfo' is required here, as either call to 460 // getFileInfo could resize the vector and we don't want to rely on order 461 // of evaluation. 462 unsigned DirInfo = getFileInfo(ContextFileEnt).DirInfo; 463 getFileInfo(FE).DirInfo = DirInfo; 464 return FE; 465} 466 467//===----------------------------------------------------------------------===// 468// File Info Management. 469//===----------------------------------------------------------------------===// 470 471 472/// getFileInfo - Return the HeaderFileInfo structure for the specified 473/// FileEntry. 474HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) { 475 if (FE->getUID() >= FileInfo.size()) 476 FileInfo.resize(FE->getUID()+1); 477 478 HeaderFileInfo &HFI = FileInfo[FE->getUID()]; 479 if (ExternalSource && !HFI.Resolved) { 480 HFI = ExternalSource->GetHeaderFileInfo(FE); 481 HFI.Resolved = true; 482 } 483 return HFI; 484} 485 486bool HeaderSearch::isFileMultipleIncludeGuarded(const FileEntry *File) { 487 // Check if we've ever seen this file as a header. 488 if (File->getUID() >= FileInfo.size()) 489 return false; 490 491 // Resolve header file info from the external source, if needed. 492 HeaderFileInfo &HFI = FileInfo[File->getUID()]; 493 if (ExternalSource && !HFI.Resolved) { 494 HFI = ExternalSource->GetHeaderFileInfo(File); 495 HFI.Resolved = true; 496 } 497 498 return HFI.isPragmaOnce || HFI.ControllingMacro || HFI.ControllingMacroID; 499} 500 501void HeaderSearch::setHeaderFileInfoForUID(HeaderFileInfo HFI, unsigned UID) { 502 if (UID >= FileInfo.size()) 503 FileInfo.resize(UID+1); 504 HFI.Resolved = true; 505 FileInfo[UID] = HFI; 506} 507 508/// ShouldEnterIncludeFile - Mark the specified file as a target of of a 509/// #include, #include_next, or #import directive. Return false if #including 510/// the file will have no effect or true if we should include it. 511bool HeaderSearch::ShouldEnterIncludeFile(const FileEntry *File, bool isImport){ 512 ++NumIncluded; // Count # of attempted #includes. 513 514 // Get information about this file. 515 HeaderFileInfo &FileInfo = getFileInfo(File); 516 517 // If this is a #import directive, check that we have not already imported 518 // this header. 519 if (isImport) { 520 // If this has already been imported, don't import it again. 521 FileInfo.isImport = true; 522 523 // Has this already been #import'ed or #include'd? 524 if (FileInfo.NumIncludes) return false; 525 } else { 526 // Otherwise, if this is a #include of a file that was previously #import'd 527 // or if this is the second #include of a #pragma once file, ignore it. 528 if (FileInfo.isImport) 529 return false; 530 } 531 532 // Next, check to see if the file is wrapped with #ifndef guards. If so, and 533 // if the macro that guards it is defined, we know the #include has no effect. 534 if (const IdentifierInfo *ControllingMacro 535 = FileInfo.getControllingMacro(ExternalLookup)) 536 if (ControllingMacro->hasMacroDefinition()) { 537 ++NumMultiIncludeFileOptzn; 538 return false; 539 } 540 541 // Increment the number of times this file has been included. 542 ++FileInfo.NumIncludes; 543 544 return true; 545} 546 547 548