1//===--- InitHeaderSearch.cpp - Initialize header search paths ------------===//
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// This file implements the InitHeaderSearch class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/Basic/DiagnosticFrontend.h"
14#include "clang/Basic/FileManager.h"
15#include "clang/Basic/LangOptions.h"
16#include "clang/Config/config.h" // C_INCLUDE_DIRS
17#include "clang/Lex/HeaderMap.h"
18#include "clang/Lex/HeaderSearch.h"
19#include "clang/Lex/HeaderSearchOptions.h"
20#include "llvm/ADT/SmallPtrSet.h"
21#include "llvm/ADT/SmallString.h"
22#include "llvm/ADT/SmallVector.h"
23#include "llvm/ADT/StringExtras.h"
24#include "llvm/ADT/Triple.h"
25#include "llvm/ADT/Twine.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/Path.h"
28#include "llvm/Support/raw_ostream.h"
29#include <optional>
30
31using namespace clang;
32using namespace clang::frontend;
33
34namespace {
35/// Holds information about a single DirectoryLookup object.
36struct DirectoryLookupInfo {
37  IncludeDirGroup Group;
38  DirectoryLookup Lookup;
39  std::optional<unsigned> UserEntryIdx;
40
41  DirectoryLookupInfo(IncludeDirGroup Group, DirectoryLookup Lookup,
42                      std::optional<unsigned> UserEntryIdx)
43      : Group(Group), Lookup(Lookup), UserEntryIdx(UserEntryIdx) {}
44};
45
46/// This class makes it easier to set the search paths of a HeaderSearch object.
47/// InitHeaderSearch stores several search path lists internally, which can be
48/// sent to a HeaderSearch object in one swoop.
49class InitHeaderSearch {
50  std::vector<DirectoryLookupInfo> IncludePath;
51  std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes;
52  HeaderSearch &Headers;
53  bool Verbose;
54  std::string IncludeSysroot;
55  bool HasSysroot;
56
57public:
58  InitHeaderSearch(HeaderSearch &HS, bool verbose, StringRef sysroot)
59      : Headers(HS), Verbose(verbose), IncludeSysroot(std::string(sysroot)),
60        HasSysroot(!(sysroot.empty() || sysroot == "/")) {}
61
62  /// Add the specified path to the specified group list, prefixing the sysroot
63  /// if used.
64  /// Returns true if the path exists, false if it was ignored.
65  bool AddPath(const Twine &Path, IncludeDirGroup Group, bool isFramework,
66               std::optional<unsigned> UserEntryIdx = std::nullopt);
67
68  /// Add the specified path to the specified group list, without performing any
69  /// sysroot remapping.
70  /// Returns true if the path exists, false if it was ignored.
71  bool AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
72                       bool isFramework,
73                       std::optional<unsigned> UserEntryIdx = std::nullopt);
74
75  /// Add the specified prefix to the system header prefix list.
76  void AddSystemHeaderPrefix(StringRef Prefix, bool IsSystemHeader) {
77    SystemHeaderPrefixes.emplace_back(std::string(Prefix), IsSystemHeader);
78  }
79
80  /// Add the necessary paths to support a gnu libstdc++.
81  /// Returns true if the \p Base path was found, false if it does not exist.
82  bool AddGnuCPlusPlusIncludePaths(StringRef Base, StringRef ArchDir,
83                                   StringRef Dir32, StringRef Dir64,
84                                   const llvm::Triple &triple);
85
86  /// Add the necessary paths to support a MinGW libstdc++.
87  void AddMinGWCPlusPlusIncludePaths(StringRef Base,
88                                     StringRef Arch,
89                                     StringRef Version);
90
91  /// Add paths that should always be searched.
92  void AddDefaultCIncludePaths(const llvm::Triple &triple,
93                               const HeaderSearchOptions &HSOpts);
94
95  /// Add paths that should be searched when compiling c++.
96  void AddDefaultCPlusPlusIncludePaths(const LangOptions &LangOpts,
97                                       const llvm::Triple &triple,
98                                       const HeaderSearchOptions &HSOpts);
99
100  /// Returns true iff AddDefaultIncludePaths should do anything.  If this
101  /// returns false, include paths should instead be handled in the driver.
102  bool ShouldAddDefaultIncludePaths(const llvm::Triple &triple);
103
104  /// Adds the default system include paths so that e.g. stdio.h is found.
105  void AddDefaultIncludePaths(const LangOptions &Lang,
106                              const llvm::Triple &triple,
107                              const HeaderSearchOptions &HSOpts);
108
109  /// Merges all search path lists into one list and send it to HeaderSearch.
110  void Realize(const LangOptions &Lang);
111};
112
113}  // end anonymous namespace.
114
115static bool CanPrefixSysroot(StringRef Path) {
116#if defined(_WIN32)
117  return !Path.empty() && llvm::sys::path::is_separator(Path[0]);
118#else
119  return llvm::sys::path::is_absolute(Path);
120#endif
121}
122
123bool InitHeaderSearch::AddPath(const Twine &Path, IncludeDirGroup Group,
124                               bool isFramework,
125                               std::optional<unsigned> UserEntryIdx) {
126  // Add the path with sysroot prepended, if desired and this is a system header
127  // group.
128  if (HasSysroot) {
129    SmallString<256> MappedPathStorage;
130    StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
131    if (CanPrefixSysroot(MappedPathStr)) {
132      return AddUnmappedPath(IncludeSysroot + Path, Group, isFramework,
133                             UserEntryIdx);
134    }
135  }
136
137  return AddUnmappedPath(Path, Group, isFramework, UserEntryIdx);
138}
139
140bool InitHeaderSearch::AddUnmappedPath(const Twine &Path, IncludeDirGroup Group,
141                                       bool isFramework,
142                                       std::optional<unsigned> UserEntryIdx) {
143  assert(!Path.isTriviallyEmpty() && "can't handle empty path here");
144
145  FileManager &FM = Headers.getFileMgr();
146  SmallString<256> MappedPathStorage;
147  StringRef MappedPathStr = Path.toStringRef(MappedPathStorage);
148
149  // If use system headers while cross-compiling, emit the warning.
150  if (HasSysroot && (MappedPathStr.startswith("/usr/include") ||
151                     MappedPathStr.startswith("/usr/local/include"))) {
152    Headers.getDiags().Report(diag::warn_poison_system_directories)
153        << MappedPathStr;
154  }
155
156  // Compute the DirectoryLookup type.
157  SrcMgr::CharacteristicKind Type;
158  if (Group == Quoted || Group == Angled || Group == IndexHeaderMap) {
159    Type = SrcMgr::C_User;
160  } else if (Group == ExternCSystem) {
161    Type = SrcMgr::C_ExternCSystem;
162  } else {
163    Type = SrcMgr::C_System;
164  }
165
166  // If the directory exists, add it.
167  if (auto DE = FM.getOptionalDirectoryRef(MappedPathStr)) {
168    IncludePath.emplace_back(Group, DirectoryLookup(*DE, Type, isFramework),
169                             UserEntryIdx);
170    return true;
171  }
172
173  // Check to see if this is an apple-style headermap (which are not allowed to
174  // be frameworks).
175  if (!isFramework) {
176    if (auto FE = FM.getFile(MappedPathStr)) {
177      if (const HeaderMap *HM = Headers.CreateHeaderMap(*FE)) {
178        // It is a headermap, add it to the search path.
179        IncludePath.emplace_back(
180            Group, DirectoryLookup(HM, Type, Group == IndexHeaderMap),
181            UserEntryIdx);
182        return true;
183      }
184    }
185  }
186
187  if (Verbose)
188    llvm::errs() << "ignoring nonexistent directory \""
189                 << MappedPathStr << "\"\n";
190  return false;
191}
192
193bool InitHeaderSearch::AddGnuCPlusPlusIncludePaths(StringRef Base,
194                                                   StringRef ArchDir,
195                                                   StringRef Dir32,
196                                                   StringRef Dir64,
197                                                   const llvm::Triple &triple) {
198  // Add the base dir
199  bool IsBaseFound = AddPath(Base, CXXSystem, false);
200
201  // Add the multilib dirs
202  llvm::Triple::ArchType arch = triple.getArch();
203  bool is64bit = arch == llvm::Triple::ppc64 || arch == llvm::Triple::x86_64;
204  if (is64bit)
205    AddPath(Base + "/" + ArchDir + "/" + Dir64, CXXSystem, false);
206  else
207    AddPath(Base + "/" + ArchDir + "/" + Dir32, CXXSystem, false);
208
209  // Add the backward dir
210  AddPath(Base + "/backward", CXXSystem, false);
211  return IsBaseFound;
212}
213
214void InitHeaderSearch::AddMinGWCPlusPlusIncludePaths(StringRef Base,
215                                                     StringRef Arch,
216                                                     StringRef Version) {
217  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++",
218          CXXSystem, false);
219  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/" + Arch,
220          CXXSystem, false);
221  AddPath(Base + "/" + Arch + "/" + Version + "/include/c++/backward",
222          CXXSystem, false);
223}
224
225void InitHeaderSearch::AddDefaultCIncludePaths(const llvm::Triple &triple,
226                                            const HeaderSearchOptions &HSOpts) {
227  if (!ShouldAddDefaultIncludePaths(triple))
228    llvm_unreachable("Include management is handled in the driver.");
229
230  llvm::Triple::OSType os = triple.getOS();
231
232  if (HSOpts.UseStandardSystemIncludes) {
233    switch (os) {
234    case llvm::Triple::CloudABI:
235    case llvm::Triple::NaCl:
236    case llvm::Triple::PS4:
237    case llvm::Triple::PS5:
238    case llvm::Triple::ELFIAMCU:
239      break;
240    case llvm::Triple::Win32:
241      if (triple.getEnvironment() != llvm::Triple::Cygnus)
242        break;
243      [[fallthrough]];
244    default:
245      // FIXME: temporary hack: hard-coded paths.
246      AddPath("/usr/local/include", System, false);
247      break;
248    }
249  }
250
251  // Builtin includes use #include_next directives and should be positioned
252  // just prior C include dirs.
253  if (HSOpts.UseBuiltinIncludes) {
254    // Ignore the sys root, we *always* look for clang headers relative to
255    // supplied path.
256    SmallString<128> P = StringRef(HSOpts.ResourceDir);
257    llvm::sys::path::append(P, "include");
258    AddUnmappedPath(P, ExternCSystem, false);
259  }
260
261  // All remaining additions are for system include directories, early exit if
262  // we aren't using them.
263  if (!HSOpts.UseStandardSystemIncludes)
264    return;
265
266  // Add dirs specified via 'configure --with-c-include-dirs'.
267  StringRef CIncludeDirs(C_INCLUDE_DIRS);
268  if (CIncludeDirs != "") {
269    SmallVector<StringRef, 5> dirs;
270    CIncludeDirs.split(dirs, ":");
271    for (StringRef dir : dirs)
272      AddPath(dir, ExternCSystem, false);
273    return;
274  }
275
276  switch (os) {
277  case llvm::Triple::CloudABI: {
278    // <sysroot>/<triple>/include
279    SmallString<128> P = StringRef(HSOpts.ResourceDir);
280    llvm::sys::path::append(P, "../../..", triple.str(), "include");
281    AddPath(P, System, false);
282    break;
283  }
284
285  case llvm::Triple::Haiku:
286    AddPath("/boot/system/non-packaged/develop/headers", System, false);
287    AddPath("/boot/system/develop/headers/os", System, false);
288    AddPath("/boot/system/develop/headers/os/app", System, false);
289    AddPath("/boot/system/develop/headers/os/arch", System, false);
290    AddPath("/boot/system/develop/headers/os/device", System, false);
291    AddPath("/boot/system/develop/headers/os/drivers", System, false);
292    AddPath("/boot/system/develop/headers/os/game", System, false);
293    AddPath("/boot/system/develop/headers/os/interface", System, false);
294    AddPath("/boot/system/develop/headers/os/kernel", System, false);
295    AddPath("/boot/system/develop/headers/os/locale", System, false);
296    AddPath("/boot/system/develop/headers/os/mail", System, false);
297    AddPath("/boot/system/develop/headers/os/media", System, false);
298    AddPath("/boot/system/develop/headers/os/midi", System, false);
299    AddPath("/boot/system/develop/headers/os/midi2", System, false);
300    AddPath("/boot/system/develop/headers/os/net", System, false);
301    AddPath("/boot/system/develop/headers/os/opengl", System, false);
302    AddPath("/boot/system/develop/headers/os/storage", System, false);
303    AddPath("/boot/system/develop/headers/os/support", System, false);
304    AddPath("/boot/system/develop/headers/os/translation", System, false);
305    AddPath("/boot/system/develop/headers/os/add-ons/graphics", System, false);
306    AddPath("/boot/system/develop/headers/os/add-ons/input_server", System, false);
307    AddPath("/boot/system/develop/headers/os/add-ons/mail_daemon", System, false);
308    AddPath("/boot/system/develop/headers/os/add-ons/registrar", System, false);
309    AddPath("/boot/system/develop/headers/os/add-ons/screen_saver", System, false);
310    AddPath("/boot/system/develop/headers/os/add-ons/tracker", System, false);
311    AddPath("/boot/system/develop/headers/os/be_apps/Deskbar", System, false);
312    AddPath("/boot/system/develop/headers/os/be_apps/NetPositive", System, false);
313    AddPath("/boot/system/develop/headers/os/be_apps/Tracker", System, false);
314    AddPath("/boot/system/develop/headers/3rdparty", System, false);
315    AddPath("/boot/system/develop/headers/bsd", System, false);
316    AddPath("/boot/system/develop/headers/glibc", System, false);
317    AddPath("/boot/system/develop/headers/posix", System, false);
318    AddPath("/boot/system/develop/headers",  System, false);
319    break;
320  case llvm::Triple::RTEMS:
321    break;
322  case llvm::Triple::Win32:
323    switch (triple.getEnvironment()) {
324    default: llvm_unreachable("Include management is handled in the driver.");
325    case llvm::Triple::Cygnus:
326      AddPath("/usr/include/w32api", System, false);
327      break;
328    case llvm::Triple::GNU:
329      break;
330    }
331    break;
332  default:
333    break;
334  }
335
336  switch (os) {
337  case llvm::Triple::CloudABI:
338  case llvm::Triple::RTEMS:
339  case llvm::Triple::NaCl:
340  case llvm::Triple::ELFIAMCU:
341    break;
342  case llvm::Triple::PS4:
343  case llvm::Triple::PS5: {
344    // <isysroot> gets prepended later in AddPath().
345    std::string BaseSDKPath;
346    if (!HasSysroot) {
347      const char *EnvVar = (os == llvm::Triple::PS4) ? "SCE_ORBIS_SDK_DIR"
348                                                     : "SCE_PROSPERO_SDK_DIR";
349      const char *envValue = getenv(EnvVar);
350      if (envValue)
351        BaseSDKPath = envValue;
352      else {
353        // HSOpts.ResourceDir variable contains the location of Clang's
354        // resource files.
355        // Assuming that Clang is configured for PS4 without
356        // --with-clang-resource-dir option, the location of Clang's resource
357        // files is <SDK_DIR>/host_tools/lib/clang
358        SmallString<128> P = StringRef(HSOpts.ResourceDir);
359        llvm::sys::path::append(P, "../../..");
360        BaseSDKPath = std::string(P.str());
361      }
362    }
363    AddPath(BaseSDKPath + "/target/include", System, false);
364    AddPath(BaseSDKPath + "/target/include_common", System, false);
365    break;
366  }
367  default:
368    AddPath("/usr/include", ExternCSystem, false);
369    break;
370  }
371}
372
373void InitHeaderSearch::AddDefaultCPlusPlusIncludePaths(
374    const LangOptions &LangOpts, const llvm::Triple &triple,
375    const HeaderSearchOptions &HSOpts) {
376  if (!ShouldAddDefaultIncludePaths(triple))
377    llvm_unreachable("Include management is handled in the driver.");
378
379  // FIXME: temporary hack: hard-coded paths.
380  llvm::Triple::OSType os = triple.getOS();
381  switch (os) {
382  case llvm::Triple::Win32:
383    switch (triple.getEnvironment()) {
384    default: llvm_unreachable("Include management is handled in the driver.");
385    case llvm::Triple::Cygnus:
386      // Cygwin-1.7
387      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.7.3");
388      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.5.3");
389      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.4");
390      // g++-4 / Cygwin-1.5
391      AddMinGWCPlusPlusIncludePaths("/usr/lib/gcc", "i686-pc-cygwin", "4.3.2");
392      break;
393    }
394    break;
395  case llvm::Triple::DragonFly:
396    AddPath("/usr/include/c++/5.0", CXXSystem, false);
397    break;
398  case llvm::Triple::Minix:
399    AddGnuCPlusPlusIncludePaths("/usr/gnu/include/c++/4.4.3",
400                                "", "", "", triple);
401    break;
402  default:
403    break;
404  }
405}
406
407bool InitHeaderSearch::ShouldAddDefaultIncludePaths(
408    const llvm::Triple &triple) {
409  switch (triple.getOS()) {
410  case llvm::Triple::AIX:
411  case llvm::Triple::Emscripten:
412  case llvm::Triple::FreeBSD:
413  case llvm::Triple::NetBSD:
414  case llvm::Triple::OpenBSD:
415  case llvm::Triple::Fuchsia:
416  case llvm::Triple::Hurd:
417  case llvm::Triple::Linux:
418  case llvm::Triple::Solaris:
419  case llvm::Triple::WASI:
420    return false;
421
422  case llvm::Triple::Win32:
423    if (triple.getEnvironment() != llvm::Triple::Cygnus ||
424        triple.isOSBinFormatMachO())
425      return false;
426    break;
427
428  case llvm::Triple::UnknownOS:
429    if (triple.isWasm())
430      return false;
431    break;
432
433  default:
434    break;
435  }
436
437  return true; // Everything else uses AddDefaultIncludePaths().
438}
439
440void InitHeaderSearch::AddDefaultIncludePaths(
441    const LangOptions &Lang, const llvm::Triple &triple,
442    const HeaderSearchOptions &HSOpts) {
443  // NB: This code path is going away. All of the logic is moving into the
444  // driver which has the information necessary to do target-specific
445  // selections of default include paths. Each target which moves there will be
446  // exempted from this logic in ShouldAddDefaultIncludePaths() until we can
447  // delete the entire pile of code.
448  if (!ShouldAddDefaultIncludePaths(triple))
449    return;
450
451  // NOTE: some additional header search logic is handled in the driver for
452  // Darwin.
453  if (triple.isOSDarwin()) {
454    if (HSOpts.UseStandardSystemIncludes) {
455      // Add the default framework include paths on Darwin.
456      if (triple.isDriverKit()) {
457        AddPath("/System/DriverKit/System/Library/Frameworks", System, true);
458      } else {
459        AddPath("/System/Library/Frameworks", System, true);
460        AddPath("/Library/Frameworks", System, true);
461      }
462    }
463    return;
464  }
465
466  if (Lang.CPlusPlus && !Lang.AsmPreprocessor &&
467      HSOpts.UseStandardCXXIncludes && HSOpts.UseStandardSystemIncludes) {
468    if (HSOpts.UseLibcxx) {
469      AddPath("/usr/include/c++/v1", CXXSystem, false);
470    } else {
471      AddDefaultCPlusPlusIncludePaths(Lang, triple, HSOpts);
472    }
473  }
474
475  AddDefaultCIncludePaths(triple, HSOpts);
476}
477
478/// If there are duplicate directory entries in the specified search list,
479/// remove the later (dead) ones.  Returns the number of non-system headers
480/// removed, which is used to update NumAngled.
481static unsigned RemoveDuplicates(std::vector<DirectoryLookupInfo> &SearchList,
482                                 unsigned First, bool Verbose) {
483  llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenDirs;
484  llvm::SmallPtrSet<const DirectoryEntry *, 8> SeenFrameworkDirs;
485  llvm::SmallPtrSet<const HeaderMap *, 8> SeenHeaderMaps;
486  unsigned NonSystemRemoved = 0;
487  for (unsigned i = First; i != SearchList.size(); ++i) {
488    unsigned DirToRemove = i;
489
490    const DirectoryLookup &CurEntry = SearchList[i].Lookup;
491
492    if (CurEntry.isNormalDir()) {
493      // If this isn't the first time we've seen this dir, remove it.
494      if (SeenDirs.insert(CurEntry.getDir()).second)
495        continue;
496    } else if (CurEntry.isFramework()) {
497      // If this isn't the first time we've seen this framework dir, remove it.
498      if (SeenFrameworkDirs.insert(CurEntry.getFrameworkDir()).second)
499        continue;
500    } else {
501      assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
502      // If this isn't the first time we've seen this headermap, remove it.
503      if (SeenHeaderMaps.insert(CurEntry.getHeaderMap()).second)
504        continue;
505    }
506
507    // If we have a normal #include dir/framework/headermap that is shadowed
508    // later in the chain by a system include location, we actually want to
509    // ignore the user's request and drop the user dir... keeping the system
510    // dir.  This is weird, but required to emulate GCC's search path correctly.
511    //
512    // Since dupes of system dirs are rare, just rescan to find the original
513    // that we're nuking instead of using a DenseMap.
514    if (CurEntry.getDirCharacteristic() != SrcMgr::C_User) {
515      // Find the dir that this is the same of.
516      unsigned FirstDir;
517      for (FirstDir = First;; ++FirstDir) {
518        assert(FirstDir != i && "Didn't find dupe?");
519
520        const DirectoryLookup &SearchEntry = SearchList[FirstDir].Lookup;
521
522        // If these are different lookup types, then they can't be the dupe.
523        if (SearchEntry.getLookupType() != CurEntry.getLookupType())
524          continue;
525
526        bool isSame;
527        if (CurEntry.isNormalDir())
528          isSame = SearchEntry.getDir() == CurEntry.getDir();
529        else if (CurEntry.isFramework())
530          isSame = SearchEntry.getFrameworkDir() == CurEntry.getFrameworkDir();
531        else {
532          assert(CurEntry.isHeaderMap() && "Not a headermap or normal dir?");
533          isSame = SearchEntry.getHeaderMap() == CurEntry.getHeaderMap();
534        }
535
536        if (isSame)
537          break;
538      }
539
540      // If the first dir in the search path is a non-system dir, zap it
541      // instead of the system one.
542      if (SearchList[FirstDir].Lookup.getDirCharacteristic() == SrcMgr::C_User)
543        DirToRemove = FirstDir;
544    }
545
546    if (Verbose) {
547      llvm::errs() << "ignoring duplicate directory \""
548                   << CurEntry.getName() << "\"\n";
549      if (DirToRemove != i)
550        llvm::errs() << "  as it is a non-system directory that duplicates "
551                     << "a system directory\n";
552    }
553    if (DirToRemove != i)
554      ++NonSystemRemoved;
555
556    // This is reached if the current entry is a duplicate.  Remove the
557    // DirToRemove (usually the current dir).
558    SearchList.erase(SearchList.begin()+DirToRemove);
559    --i;
560  }
561  return NonSystemRemoved;
562}
563
564/// Extract DirectoryLookups from DirectoryLookupInfos.
565static std::vector<DirectoryLookup>
566extractLookups(const std::vector<DirectoryLookupInfo> &Infos) {
567  std::vector<DirectoryLookup> Lookups;
568  Lookups.reserve(Infos.size());
569  llvm::transform(Infos, std::back_inserter(Lookups),
570                  [](const DirectoryLookupInfo &Info) { return Info.Lookup; });
571  return Lookups;
572}
573
574/// Collect the mapping between indices of DirectoryLookups and UserEntries.
575static llvm::DenseMap<unsigned, unsigned>
576mapToUserEntries(const std::vector<DirectoryLookupInfo> &Infos) {
577  llvm::DenseMap<unsigned, unsigned> LookupsToUserEntries;
578  for (unsigned I = 0, E = Infos.size(); I < E; ++I) {
579    // Check whether this DirectoryLookup maps to a HeaderSearch::UserEntry.
580    if (Infos[I].UserEntryIdx)
581      LookupsToUserEntries.insert({I, *Infos[I].UserEntryIdx});
582  }
583  return LookupsToUserEntries;
584}
585
586void InitHeaderSearch::Realize(const LangOptions &Lang) {
587  // Concatenate ANGLE+SYSTEM+AFTER chains together into SearchList.
588  std::vector<DirectoryLookupInfo> SearchList;
589  SearchList.reserve(IncludePath.size());
590
591  // Quoted arguments go first.
592  for (auto &Include : IncludePath)
593    if (Include.Group == Quoted)
594      SearchList.push_back(Include);
595
596  // Deduplicate and remember index.
597  RemoveDuplicates(SearchList, 0, Verbose);
598  unsigned NumQuoted = SearchList.size();
599
600  for (auto &Include : IncludePath)
601    if (Include.Group == Angled || Include.Group == IndexHeaderMap)
602      SearchList.push_back(Include);
603
604  RemoveDuplicates(SearchList, NumQuoted, Verbose);
605  unsigned NumAngled = SearchList.size();
606
607  for (auto &Include : IncludePath)
608    if (Include.Group == System || Include.Group == ExternCSystem ||
609        (!Lang.ObjC && !Lang.CPlusPlus && Include.Group == CSystem) ||
610        (/*FIXME !Lang.ObjC && */ Lang.CPlusPlus &&
611         Include.Group == CXXSystem) ||
612        (Lang.ObjC && !Lang.CPlusPlus && Include.Group == ObjCSystem) ||
613        (Lang.ObjC && Lang.CPlusPlus && Include.Group == ObjCXXSystem))
614      SearchList.push_back(Include);
615
616  for (auto &Include : IncludePath)
617    if (Include.Group == After)
618      SearchList.push_back(Include);
619
620  // Remove duplicates across both the Angled and System directories.  GCC does
621  // this and failing to remove duplicates across these two groups breaks
622  // #include_next.
623  unsigned NonSystemRemoved = RemoveDuplicates(SearchList, NumQuoted, Verbose);
624  NumAngled -= NonSystemRemoved;
625
626  bool DontSearchCurDir = false;  // TODO: set to true if -I- is set?
627  Headers.SetSearchPaths(extractLookups(SearchList), NumQuoted, NumAngled,
628                         DontSearchCurDir, mapToUserEntries(SearchList));
629
630  Headers.SetSystemHeaderPrefixes(SystemHeaderPrefixes);
631
632  // If verbose, print the list of directories that will be searched.
633  if (Verbose) {
634    llvm::errs() << "#include \"...\" search starts here:\n";
635    for (unsigned i = 0, e = SearchList.size(); i != e; ++i) {
636      if (i == NumQuoted)
637        llvm::errs() << "#include <...> search starts here:\n";
638      StringRef Name = SearchList[i].Lookup.getName();
639      const char *Suffix;
640      if (SearchList[i].Lookup.isNormalDir())
641        Suffix = "";
642      else if (SearchList[i].Lookup.isFramework())
643        Suffix = " (framework directory)";
644      else {
645        assert(SearchList[i].Lookup.isHeaderMap() && "Unknown DirectoryLookup");
646        Suffix = " (headermap)";
647      }
648      llvm::errs() << " " << Name << Suffix << "\n";
649    }
650    llvm::errs() << "End of search list.\n";
651  }
652}
653
654void clang::ApplyHeaderSearchOptions(HeaderSearch &HS,
655                                     const HeaderSearchOptions &HSOpts,
656                                     const LangOptions &Lang,
657                                     const llvm::Triple &Triple) {
658  InitHeaderSearch Init(HS, HSOpts.Verbose, HSOpts.Sysroot);
659
660  // Add the user defined entries.
661  for (unsigned i = 0, e = HSOpts.UserEntries.size(); i != e; ++i) {
662    const HeaderSearchOptions::Entry &E = HSOpts.UserEntries[i];
663    if (E.IgnoreSysRoot) {
664      Init.AddUnmappedPath(E.Path, E.Group, E.IsFramework, i);
665    } else {
666      Init.AddPath(E.Path, E.Group, E.IsFramework, i);
667    }
668  }
669
670  Init.AddDefaultIncludePaths(Lang, Triple, HSOpts);
671
672  for (unsigned i = 0, e = HSOpts.SystemHeaderPrefixes.size(); i != e; ++i)
673    Init.AddSystemHeaderPrefix(HSOpts.SystemHeaderPrefixes[i].Prefix,
674                               HSOpts.SystemHeaderPrefixes[i].IsSystemHeader);
675
676  if (HSOpts.UseBuiltinIncludes) {
677    // Set up the builtin include directory in the module map.
678    SmallString<128> P = StringRef(HSOpts.ResourceDir);
679    llvm::sys::path::append(P, "include");
680    if (auto Dir = HS.getFileMgr().getDirectory(P))
681      HS.getModuleMap().setBuiltinIncludeDir(*Dir);
682  }
683
684  Init.Realize(Lang);
685}
686