blob: 03426298277089ca19faaf66ea37b5b1d14f5960 [file] [log] [blame]
//===--- HeaderSearch.h - Resolve Header File Locations ---------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file defines the HeaderSearch interface.
#include "clang/Lex/DirectoryLookup.h"
#include "clang/Lex/ModuleMap.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Support/Allocator.h"
#include <memory>
#include <vector>
namespace clang {
class DiagnosticsEngine;
class ExternalIdentifierLookup;
class FileEntry;
class FileManager;
class HeaderSearchOptions;
class IdentifierInfo;
/// \brief The preprocessor keeps track of this information for each
/// file that is \#included.
struct HeaderFileInfo {
/// \brief True if this is a \#import'd or \#pragma once file.
unsigned isImport : 1;
/// \brief True if this is a \#pragma once file.
unsigned isPragmaOnce : 1;
/// DirInfo - Keep track of whether this is a system header, and if so,
/// whether it is C++ clean or not. This can be set by the include paths or
/// by \#pragma gcc system_header. This is an instance of
/// SrcMgr::CharacteristicKind.
unsigned DirInfo : 2;
/// \brief Whether this header file info was supplied by an external source.
unsigned External : 1;
/// \brief Whether this header is part of a module.
unsigned isModuleHeader : 1;
/// \brief Whether this header is part of the module that we are building.
unsigned isCompilingModuleHeader : 1;
/// \brief Whether this header is part of the module that we are building.
/// This is an instance of ModuleMap::ModuleHeaderRole.
unsigned HeaderRole : 2;
/// \brief Whether this structure is considered to already have been
/// "resolved", meaning that it was loaded from the external source.
unsigned Resolved : 1;
/// \brief Whether this is a header inside a framework that is currently
/// being built.
/// When a framework is being built, the headers have not yet been placed
/// into the appropriate framework subdirectories, and therefore are
/// provided via a header map. This bit indicates when this is one of
/// those framework headers.
unsigned IndexHeaderMapHeader : 1;
/// \brief Whether this file had been looked up as a header.
unsigned IsValid : 1;
/// \brief The number of times the file has been included already.
unsigned short NumIncludes;
/// \brief The ID number of the controlling macro.
/// This ID number will be non-zero when there is a controlling
/// macro whose IdentifierInfo may not yet have been loaded from
/// external storage.
unsigned ControllingMacroID;
/// If this file has a \#ifndef XXX (or equivalent) guard that
/// protects the entire contents of the file, this is the identifier
/// for the macro that controls whether or not it has any effect.
/// Note: Most clients should use getControllingMacro() to access
/// the controlling macro of this header, since
/// getControllingMacro() is able to load a controlling macro from
/// external storage.
const IdentifierInfo *ControllingMacro;
/// \brief If this header came from a framework include, this is the name
/// of the framework.
StringRef Framework;
: isImport(false), isPragmaOnce(false), DirInfo(SrcMgr::C_User),
External(false), isModuleHeader(false), isCompilingModuleHeader(false),
Resolved(false), IndexHeaderMapHeader(false), IsValid(0),
NumIncludes(0), ControllingMacroID(0), ControllingMacro(nullptr) {}
/// \brief Retrieve the controlling macro for this header file, if
/// any.
const IdentifierInfo *getControllingMacro(ExternalIdentifierLookup *External);
/// \brief Determine whether this is a non-default header file info, e.g.,
/// it corresponds to an actual header we've included or tried to include.
bool isNonDefault() const {
return isImport || isPragmaOnce || NumIncludes || ControllingMacro ||
/// \brief Get the HeaderRole properly typed.
ModuleMap::ModuleHeaderRole getHeaderRole() const {
return static_cast<ModuleMap::ModuleHeaderRole>(HeaderRole);
/// \brief Set the HeaderRole properly typed.
void setHeaderRole(ModuleMap::ModuleHeaderRole Role) {
HeaderRole = Role;
/// \brief An external source of header file information, which may supply
/// information about header files already included.
class ExternalHeaderFileInfoSource {
virtual ~ExternalHeaderFileInfoSource();
/// \brief Retrieve the header file information for the given file entry.
/// \returns Header file information for the given file entry, with the
/// \c External bit set. If the file entry is not known, return a
/// default-constructed \c HeaderFileInfo.
virtual HeaderFileInfo GetHeaderFileInfo(const FileEntry *FE) = 0;
/// \brief Encapsulates the information needed to find the file referenced
/// by a \#include or \#include_next, (sub-)framework lookup, etc.
class HeaderSearch {
/// This structure is used to record entries in our framework cache.
struct FrameworkCacheEntry {
/// The directory entry which should be used for the cached framework.
const DirectoryEntry *Directory;
/// Whether this framework has been "user-specified" to be treated as if it
/// were a system framework (even if it was found outside a system framework
/// directory).
bool IsUserSpecifiedSystemFramework;
/// \brief Header-search options used to initialize this header search.
IntrusiveRefCntPtr<HeaderSearchOptions> HSOpts;
DiagnosticsEngine &Diags;
FileManager &FileMgr;
/// \#include search path information. Requests for \#include "x" search the
/// directory of the \#including file first, then each directory in SearchDirs
/// consecutively. Requests for <x> search the current dir first, then each
/// directory in SearchDirs, starting at AngledDirIdx, consecutively. If
/// NoCurDirSearch is true, then the check for the file in the current
/// directory is suppressed.
std::vector<DirectoryLookup> SearchDirs;
unsigned AngledDirIdx;
unsigned SystemDirIdx;
bool NoCurDirSearch;
/// \brief \#include prefixes for which the 'system header' property is
/// overridden.
/// For a \#include "x" or \#include \<x> directive, the last string in this
/// list which is a prefix of 'x' determines whether the file is treated as
/// a system header.
std::vector<std::pair<std::string, bool> > SystemHeaderPrefixes;
/// \brief The path to the module cache.
std::string ModuleCachePath;
/// \brief All of the preprocessor-specific data about files that are
/// included, indexed by the FileEntry's UID.
std::vector<HeaderFileInfo> FileInfo;
/// Keeps track of each lookup performed by LookupFile.
struct LookupFileCacheInfo {
/// Starting index in SearchDirs that the cached search was performed from.
/// If there is a hit and this value doesn't match the current query, the
/// cache has to be ignored.
unsigned StartIdx;
/// The entry in SearchDirs that satisfied the query.
unsigned HitIdx;
/// This is non-null if the original filename was mapped to a framework
/// include via a headermap.
const char *MappedName;
/// Default constructor -- Initialize all members with zero.
LookupFileCacheInfo(): StartIdx(0), HitIdx(0), MappedName(nullptr) {}
void reset(unsigned StartIdx) {
this->StartIdx = StartIdx;
this->MappedName = nullptr;
llvm::StringMap<LookupFileCacheInfo, llvm::BumpPtrAllocator> LookupFileCache;
/// \brief Collection mapping a framework or subframework
/// name like "Carbon" to the Carbon.framework directory.
llvm::StringMap<FrameworkCacheEntry, llvm::BumpPtrAllocator> FrameworkMap;
/// IncludeAliases - maps include file names (including the quotes or
/// angle brackets) to other include file names. This is used to support the
/// include_alias pragma for Microsoft compatibility.
typedef llvm::StringMap<std::string, llvm::BumpPtrAllocator>
std::unique_ptr<IncludeAliasMap> IncludeAliases;
/// HeaderMaps - This is a mapping from FileEntry -> HeaderMap, uniquing
/// headermaps. This vector owns the headermap.
std::vector<std::pair<const FileEntry*, const HeaderMap*> > HeaderMaps;
/// \brief The mapping between modules and headers.
mutable ModuleMap ModMap;
/// \brief Describes whether a given directory has a module map in it.
llvm::DenseMap<const DirectoryEntry *, bool> DirectoryHasModuleMap;
/// \brief Uniqued set of framework names, which is used to track which
/// headers were included as framework headers.
llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames;
/// \brief Entity used to resolve the identifier IDs of controlling
/// macros into IdentifierInfo pointers, as needed.
ExternalIdentifierLookup *ExternalLookup;
/// \brief Entity used to look up stored header file information.
ExternalHeaderFileInfoSource *ExternalSource;
// Various statistics we track for performance analysis.
unsigned NumIncluded;
unsigned NumMultiIncludeFileOptzn;
unsigned NumFrameworkLookups, NumSubFrameworkLookups;
bool EnabledModules;
// HeaderSearch doesn't support default or copy construction.
HeaderSearch(const HeaderSearch&) LLVM_DELETED_FUNCTION;
void operator=(const HeaderSearch&) LLVM_DELETED_FUNCTION;
friend class DirectoryLookup;
HeaderSearch(IntrusiveRefCntPtr<HeaderSearchOptions> HSOpts,
SourceManager &SourceMgr, DiagnosticsEngine &Diags,
const LangOptions &LangOpts, const TargetInfo *Target);
/// \brief Retrieve the header-search options with which this header search
/// was initialized.
HeaderSearchOptions &getHeaderSearchOpts() const { return *HSOpts; }
FileManager &getFileMgr() const { return FileMgr; }
/// \brief Interface for setting the file search paths.
void SetSearchPaths(const std::vector<DirectoryLookup> &dirs,
unsigned angledDirIdx, unsigned systemDirIdx,
bool noCurDirSearch) {
assert(angledDirIdx <= systemDirIdx && systemDirIdx <= dirs.size() &&
"Directory indicies are unordered");
SearchDirs = dirs;
AngledDirIdx = angledDirIdx;
SystemDirIdx = systemDirIdx;
NoCurDirSearch = noCurDirSearch;
/// \brief Add an additional search path.
void AddSearchPath(const DirectoryLookup &dir, bool isAngled) {
unsigned idx = isAngled ? SystemDirIdx : AngledDirIdx;
SearchDirs.insert(SearchDirs.begin() + idx, dir);
if (!isAngled)
/// \brief Set the list of system header prefixes.
void SetSystemHeaderPrefixes(ArrayRef<std::pair<std::string, bool> > P) {
SystemHeaderPrefixes.assign(P.begin(), P.end());
/// \brief Checks whether the map exists or not.
bool HasIncludeAliasMap() const { return (bool)IncludeAliases; }
/// \brief Map the source include name to the dest include name.
/// The Source should include the angle brackets or quotes, the dest
/// should not. This allows for distinction between <> and "" headers.
void AddIncludeAlias(StringRef Source, StringRef Dest) {
if (!IncludeAliases)
IncludeAliases.reset(new IncludeAliasMap);
(*IncludeAliases)[Source] = Dest;
/// MapHeaderToIncludeAlias - Maps one header file name to a different header
/// file name, for use with the include_alias pragma. Note that the source
/// file name should include the angle brackets or quotes. Returns StringRef
/// as null if the header cannot be mapped.
StringRef MapHeaderToIncludeAlias(StringRef Source) {
assert(IncludeAliases && "Trying to map headers when there's no map");
// Do any filename replacements before anything else
IncludeAliasMap::const_iterator Iter = IncludeAliases->find(Source);
if (Iter != IncludeAliases->end())
return Iter->second;
return StringRef();
/// \brief Set the path to the module cache.
void setModuleCachePath(StringRef CachePath) {
ModuleCachePath = CachePath;
/// \brief Retrieve the path to the module cache.
StringRef getModuleCachePath() const { return ModuleCachePath; }
/// \brief Consider modules when including files from this directory.
void setDirectoryHasModuleMap(const DirectoryEntry* Dir) {
DirectoryHasModuleMap[Dir] = true;
/// \brief Forget everything we know about headers so far.
void ClearFileInfo() {
void SetExternalLookup(ExternalIdentifierLookup *EIL) {
ExternalLookup = EIL;
ExternalIdentifierLookup *getExternalLookup() const {
return ExternalLookup;
/// \brief Set the external source of header information.
void SetExternalSource(ExternalHeaderFileInfoSource *ES) {
ExternalSource = ES;
/// \brief Set the target information for the header search, if not
/// already known.
void setTarget(const TargetInfo &Target);
/// \brief Given a "foo" or \<foo> reference, look up the indicated file,
/// return null on failure.
/// \returns If successful, this returns 'UsedDir', the DirectoryLookup member
/// the file was found in, or null if not applicable.
/// \param IncludeLoc Used for diagnostics if valid.
/// \param isAngled indicates whether the file reference is a <> reference.
/// \param CurDir If non-null, the file was found in the specified directory
/// search location. This is used to implement \#include_next.
/// \param Includers Indicates where the \#including file(s) are, in case
/// relative searches are needed. In reverse order of inclusion.
/// \param SearchPath If non-null, will be set to the search path relative
/// to which the file was found. If the include path is absolute, SearchPath
/// will be set to an empty string.
/// \param RelativePath If non-null, will be set to the path relative to
/// SearchPath at which the file was found. This only differs from the
/// Filename for framework includes.
/// \param SuggestedModule If non-null, and the file found is semantically
/// part of a known module, this will be set to the module that should
/// be imported instead of preprocessing/parsing the file found.
const FileEntry *LookupFile(StringRef Filename, SourceLocation IncludeLoc,
bool isAngled, const DirectoryLookup *FromDir,
const DirectoryLookup *&CurDir,
ArrayRef<const FileEntry *> Includers,
SmallVectorImpl<char> *SearchPath,
SmallVectorImpl<char> *RelativePath,
ModuleMap::KnownHeader *SuggestedModule,
bool SkipCache = false);
/// \brief Look up a subframework for the specified \#include file.
/// For example, if \#include'ing <HIToolbox/HIToolbox.h> from
/// within ".../Carbon.framework/Headers/Carbon.h", check to see if
/// HIToolbox is a subframework within Carbon.framework. If so, return
/// the FileEntry for the designated file, otherwise return null.
const FileEntry *LookupSubframeworkHeader(
StringRef Filename,
const FileEntry *RelativeFileEnt,
SmallVectorImpl<char> *SearchPath,
SmallVectorImpl<char> *RelativePath,
ModuleMap::KnownHeader *SuggestedModule);
/// \brief Look up the specified framework name in our framework cache.
/// \returns The DirectoryEntry it is in if we know, null otherwise.
FrameworkCacheEntry &LookupFrameworkCache(StringRef FWName) {
return FrameworkMap.GetOrCreateValue(FWName).getValue();
/// \brief Mark the specified file as a target of of a \#include,
/// \#include_next, or \#import directive.
/// \return false if \#including the file will have no effect or true
/// if we should include it.
bool ShouldEnterIncludeFile(const FileEntry *File, bool isImport);
/// \brief Return whether the specified file is a normal header,
/// a system header, or a C++ friendly system header.
SrcMgr::CharacteristicKind getFileDirFlavor(const FileEntry *File) {
return (SrcMgr::CharacteristicKind)getFileInfo(File).DirInfo;
/// \brief Mark the specified file as a "once only" file, e.g. due to
/// \#pragma once.
void MarkFileIncludeOnce(const FileEntry *File) {
HeaderFileInfo &FI = getFileInfo(File);
FI.isImport = true;
FI.isPragmaOnce = true;
/// \brief Mark the specified file as a system header, e.g. due to
/// \#pragma GCC system_header.
void MarkFileSystemHeader(const FileEntry *File) {
getFileInfo(File).DirInfo = SrcMgr::C_System;
/// \brief Mark the specified file as part of a module.
void MarkFileModuleHeader(const FileEntry *File,
ModuleMap::ModuleHeaderRole Role,
bool IsCompiledModuleHeader);
/// \brief Increment the count for the number of times the specified
/// FileEntry has been entered.
void IncrementIncludeCount(const FileEntry *File) {
/// \brief Mark the specified file as having a controlling macro.
/// This is used by the multiple-include optimization to eliminate
/// no-op \#includes.
void SetFileControllingMacro(const FileEntry *File,
const IdentifierInfo *ControllingMacro) {
getFileInfo(File).ControllingMacro = ControllingMacro;
/// \brief Return true if this is the first time encountering this header.
bool FirstTimeLexingFile(const FileEntry *File) {
return getFileInfo(File).NumIncludes == 1;
/// \brief Determine whether this file is intended to be safe from
/// multiple inclusions, e.g., it has \#pragma once or a controlling
/// macro.
/// This routine does not consider the effect of \#import
bool isFileMultipleIncludeGuarded(const FileEntry *File);
/// CreateHeaderMap - This method returns a HeaderMap for the specified
/// FileEntry, uniquing them through the 'HeaderMaps' datastructure.
const HeaderMap *CreateHeaderMap(const FileEntry *FE);
/// Returns true if modules are enabled.
bool enabledModules() const { return EnabledModules; }
/// \brief Retrieve the name of the module file that should be used to
/// load the given module.
/// \param Module The module whose module file name will be returned.
/// \returns The name of the module file that corresponds to this module,
/// or an empty string if this module does not correspond to any module file.
std::string getModuleFileName(Module *Module);
/// \brief Retrieve the name of the module file that should be used to
/// load a module with the given name.
/// \param ModuleName The module whose module file name will be returned.
/// \param ModuleMapPath A path that when combined with \c ModuleName
/// uniquely identifies this module. See Module::ModuleMap.
/// \returns The name of the module file that corresponds to this module,
/// or an empty string if this module does not correspond to any module file.
std::string getModuleFileName(StringRef ModuleName, StringRef ModuleMapPath);
/// \brief Lookup a module Search for a module with the given name.
/// \param ModuleName The name of the module we're looking for.
/// \param AllowSearch Whether we are allowed to search in the various
/// search directories to produce a module definition. If not, this lookup
/// will only return an already-known module.
/// \returns The module with the given name.
Module *lookupModule(StringRef ModuleName, bool AllowSearch = true);
/// \brief Try to find a module map file in the given directory, returning
/// \c nullptr if none is found.
const FileEntry *lookupModuleMapFile(const DirectoryEntry *Dir,
bool IsFramework);
void IncrementFrameworkLookupCount() { ++NumFrameworkLookups; }
/// \brief Determine whether there is a module map that may map the header
/// with the given file name to a (sub)module.
/// Always returns false if modules are disabled.
/// \param Filename The name of the file.
/// \param Root The "root" directory, at which we should stop looking for
/// module maps.
/// \param IsSystem Whether the directories we're looking at are system
/// header directories.
bool hasModuleMap(StringRef Filename, const DirectoryEntry *Root,
bool IsSystem);
/// \brief Retrieve the module that corresponds to the given file, if any.
/// \param File The header that we wish to map to a module.
ModuleMap::KnownHeader findModuleForHeader(const FileEntry *File) const;
/// \brief Read the contents of the given module map file.
/// \param File The module map file.
/// \param IsSystem Whether this file is in a system header directory.
/// \returns true if an error occurred, false otherwise.
bool loadModuleMapFile(const FileEntry *File, bool IsSystem);
/// \brief Collect the set of all known, top-level modules.
/// \param Modules Will be filled with the set of known, top-level modules.
void collectAllModules(SmallVectorImpl<Module *> &Modules);
/// \brief Load all known, top-level system modules.
void loadTopLevelSystemModules();
/// \brief Retrieve a module with the given name, which may be part of the
/// given framework.
/// \param Name The name of the module to retrieve.
/// \param Dir The framework directory (e.g., ModuleName.framework).
/// \param IsSystem Whether the framework directory is part of the system
/// frameworks.
/// \returns The module, if found; otherwise, null.
Module *loadFrameworkModule(StringRef Name,
const DirectoryEntry *Dir,
bool IsSystem);
/// \brief Load all of the module maps within the immediate subdirectories
/// of the given search directory.
void loadSubdirectoryModuleMaps(DirectoryLookup &SearchDir);
/// \brief Return the HeaderFileInfo structure for the specified FileEntry.
const HeaderFileInfo &getFileInfo(const FileEntry *FE) const {
return const_cast<HeaderSearch*>(this)->getFileInfo(FE);
/// \brief Retrieve the module map.
ModuleMap &getModuleMap() { return ModMap; }
unsigned header_file_size() const { return FileInfo.size(); }
/// \brief Get a \c HeaderFileInfo structure for the specified \c FileEntry,
/// if one exists.
bool tryGetFileInfo(const FileEntry *FE, HeaderFileInfo &Result) const;
// Used by external tools
typedef std::vector<DirectoryLookup>::const_iterator search_dir_iterator;
search_dir_iterator search_dir_begin() const { return SearchDirs.begin(); }
search_dir_iterator search_dir_end() const { return SearchDirs.end(); }
unsigned search_dir_size() const { return SearchDirs.size(); }
search_dir_iterator quoted_dir_begin() const {
return SearchDirs.begin();
search_dir_iterator quoted_dir_end() const {
return SearchDirs.begin() + AngledDirIdx;
search_dir_iterator angled_dir_begin() const {
return SearchDirs.begin() + AngledDirIdx;
search_dir_iterator angled_dir_end() const {
return SearchDirs.begin() + SystemDirIdx;
search_dir_iterator system_dir_begin() const {
return SearchDirs.begin() + SystemDirIdx;
search_dir_iterator system_dir_end() const { return SearchDirs.end(); }
/// \brief Retrieve a uniqued framework name.
StringRef getUniqueFrameworkName(StringRef Framework);
void PrintStats();
size_t getTotalMemory() const;
static std::string NormalizeDashIncludePath(StringRef File,
FileManager &FileMgr);
/// \brief Describes what happened when we tried to load a module map file.
enum LoadModuleMapResult {
/// \brief The module map file had already been loaded.
/// \brief The module map file was loaded by this invocation.
/// \brief There is was directory with the given name.
/// \brief There was either no module map file or the module map file was
/// invalid.
LoadModuleMapResult loadModuleMapFileImpl(const FileEntry *File,
bool IsSystem);
/// \brief Try to load the module map file in the given directory.
/// \param DirName The name of the directory where we will look for a module
/// map file.
/// \param IsSystem Whether this is a system header directory.
/// \param IsFramework Whether this is a framework directory.
/// \returns The result of attempting to load the module map file from the
/// named directory.
LoadModuleMapResult loadModuleMapFile(StringRef DirName, bool IsSystem,
bool IsFramework);
/// \brief Try to load the module map file in the given directory.
/// \param Dir The directory where we will look for a module map file.
/// \param IsSystem Whether this is a system header directory.
/// \param IsFramework Whether this is a framework directory.
/// \returns The result of attempting to load the module map file from the
/// named directory.
LoadModuleMapResult loadModuleMapFile(const DirectoryEntry *Dir,
bool IsSystem, bool IsFramework);
/// \brief Return the HeaderFileInfo structure for the specified FileEntry.
HeaderFileInfo &getFileInfo(const FileEntry *FE);
} // end namespace clang