Stage two of getting CFE top correct.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@39734 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 319 insertions, 0 deletions

diff --git a/Lex/HeaderSearch.cpp b/Lex/HeaderSearch.cpp
new file mode 100644
index 0000000000..520205e1da
--- /dev/null
+++ b/Lex/HeaderSearch.cpp
@@ -0,0 +1,319 @@
+//===--- HeaderSearch.cpp - Resolve Header File Locations ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements the DirectoryLookup and HeaderSearch interfaces.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/FileManager.h"
+#include "clang/Lex/HeaderSearch.h"
+#include "clang/Lex/IdentifierTable.h"
+#include "llvm/System/Path.h"
+#include "llvm/ADT/SmallString.h"
+using namespace clang;
+
+HeaderSearch::HeaderSearch(FileManager &FM) : FileMgr(FM), FrameworkMap(64) {
+  SystemDirIdx = 0;
+  NoCurDirSearch = false;
+  
+  NumIncluded = 0;
+  NumMultiIncludeFileOptzn = 0;
+  NumFrameworkLookups = NumSubFrameworkLookups = 0;
+}
+
+void HeaderSearch::PrintStats() {
+  fprintf(stderr, "\n*** HeaderSearch Stats:\n");
+  fprintf(stderr, "%d files tracked.\n", (int)FileInfo.size());
+  unsigned NumOnceOnlyFiles = 0, MaxNumIncludes = 0, NumSingleIncludedFiles = 0;
+  for (unsigned i = 0, e = FileInfo.size(); i != e; ++i) {
+    NumOnceOnlyFiles += FileInfo[i].isImport;
+    if (MaxNumIncludes < FileInfo[i].NumIncludes)
+      MaxNumIncludes = FileInfo[i].NumIncludes;
+    NumSingleIncludedFiles += FileInfo[i].NumIncludes == 1;
+  }
+  fprintf(stderr, "  %d #import/#pragma once files.\n", NumOnceOnlyFiles);
+  fprintf(stderr, "  %d included exactly once.\n", NumSingleIncludedFiles);
+  fprintf(stderr, "  %d max times a file is included.\n", MaxNumIncludes);
+  
+  fprintf(stderr, "  %d #include/#include_next/#import.\n", NumIncluded);
+  fprintf(stderr, "    %d #includes skipped due to"
+          " the multi-include optimization.\n", NumMultiIncludeFileOptzn);
+  
+  fprintf(stderr, "%d framework lookups.\n", NumFrameworkLookups);
+  fprintf(stderr, "%d subframework lookups.\n", NumSubFrameworkLookups);
+}
+
+//===----------------------------------------------------------------------===//
+// Header File Location.
+//===----------------------------------------------------------------------===//
+
+const FileEntry *HeaderSearch::DoFrameworkLookup(const DirectoryEntry *Dir,
+                                                 const char *FilenameStart,
+                                                 const char *FilenameEnd) {
+  // Framework names must have a '/' in the filename.
+  const char *SlashPos = std::find(FilenameStart, FilenameEnd, '/');
+  if (SlashPos == FilenameEnd) return 0;
+  
+  llvm::StringMapEntry<const DirectoryEntry *> &CacheLookup =
+    FrameworkMap.GetOrCreateValue(FilenameStart, SlashPos);
+  
+  // If it is some other directory, fail.
+  if (CacheLookup.getValue() && CacheLookup.getValue() != Dir)
+    return 0;
+
+  // FrameworkName = "/System/Library/Frameworks/"
+  llvm::SmallString<1024> FrameworkName;
+  FrameworkName += Dir->getName();
+  if (FrameworkName.empty() || FrameworkName.back() != '/')
+    FrameworkName.push_back('/');
+  
+  // FrameworkName = "/System/Library/Frameworks/Cocoa"
+  FrameworkName.append(FilenameStart, SlashPos);
+  
+  // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/"
+  FrameworkName += ".framework/";
+ 
+  if (CacheLookup.getValue() == 0) {
+    ++NumFrameworkLookups;
+    
+    // If the framework dir doesn't exist, we fail.
+    if (!llvm::sys::Path(std::string(FrameworkName.begin(), 
+                                     FrameworkName.end())).exists())
+      return 0;
+    
+    // Otherwise, if it does, remember that this is the right direntry for this
+    // framework.
+    CacheLookup.setValue(Dir);
+  }
+  
+  // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h"
+  unsigned OrigSize = FrameworkName.size();
+  
+  FrameworkName += "Headers/";
+  FrameworkName.append(SlashPos+1, FilenameEnd);
+  if (const FileEntry *FE = FileMgr.getFile(FrameworkName.begin(),
+                                            FrameworkName.end())) {
+    return FE;
+  }
+  
+  // Check "/System/Library/Frameworks/Cocoa.framework/PrivateHeaders/file.h"
+  const char *Private = "Private";
+  FrameworkName.insert(FrameworkName.begin()+OrigSize, Private, 
+                       Private+strlen(Private));
+  return FileMgr.getFile(FrameworkName.begin(), FrameworkName.end());
+}
+
+/// LookupFile - Given a "foo" or <foo> reference, look up the indicated file,
+/// return null on failure.  isAngled indicates whether the file reference is
+/// for system #include's or not (i.e. using <> instead of "").  CurFileEnt, if
+/// non-null, indicates where the #including file is, in case a relative search
+/// is needed.
+const FileEntry *HeaderSearch::LookupFile(const char *FilenameStart,
+                                          const char *FilenameEnd, 
+                                          bool isAngled,
+                                          const DirectoryLookup *FromDir,
+                                          const DirectoryLookup *&CurDir,
+                                          const FileEntry *CurFileEnt) {
+  // If 'Filename' is absolute, check to see if it exists and no searching.
+  // FIXME: Portability.  This should be a sys::Path interface, this doesn't
+  // handle things like C:\foo.txt right, nor win32 \\network\device\blah.
+  if (FilenameStart[0] == '/') {
+    CurDir = 0;
+
+    // If this was an #include_next "/absolute/file", fail.
+    if (FromDir) return 0;
+    
+    // Otherwise, just return the file.
+    return FileMgr.getFile(FilenameStart, FilenameEnd);
+  }
+  
+  llvm::SmallString<1024> TmpDir;
+  
+  // Step #0, unless disabled, check to see if the file is in the #includer's
+  // directory.  This search is not done for <> headers.
+  if (CurFileEnt && !isAngled && !NoCurDirSearch) {
+    // Concatenate the requested file onto the directory.
+    // FIXME: Portability.  Filename concatenation should be in sys::Path.
+    TmpDir += CurFileEnt->getDir()->getName();
+    TmpDir.push_back('/');
+    TmpDir.append(FilenameStart, FilenameEnd);
+    if (const FileEntry *FE = FileMgr.getFile(TmpDir.begin(), TmpDir.end())) {
+      // Leave CurDir unset.
+      
+      // This file is a system header or C++ unfriendly if the old file is.
+      getFileInfo(FE).DirInfo = getFileInfo(CurFileEnt).DirInfo;
+      return FE;
+    }
+    TmpDir.clear();
+  }
+  
+  CurDir = 0;
+
+  // If this is a system #include, ignore the user #include locs.
+  unsigned i = isAngled ? SystemDirIdx : 0;
+  
+  // If this is a #include_next request, start searching after the directory the
+  // file was found in.
+  if (FromDir)
+    i = FromDir-&SearchDirs[0];
+  
+  // Check each directory in sequence to see if it contains this file.
+  for (; i != SearchDirs.size(); ++i) {
+    const FileEntry *FE = 0;
+    if (!SearchDirs[i].isFramework()) {
+      // FIXME: Portability.  Adding file to dir should be in sys::Path.
+      // Concatenate the requested file onto the directory.
+      TmpDir.clear();
+      TmpDir += SearchDirs[i].getDir()->getName();
+      TmpDir.push_back('/');
+      TmpDir.append(FilenameStart, FilenameEnd);
+      FE = FileMgr.getFile(TmpDir.begin(), TmpDir.end());
+    } else {
+      FE = DoFrameworkLookup(SearchDirs[i].getDir(), FilenameStart,FilenameEnd);
+    }
+    
+    if (FE) {
+      CurDir = &SearchDirs[i];
+      
+      // This file is a system header or C++ unfriendly if the dir is.
+      getFileInfo(FE).DirInfo = CurDir->getDirCharacteristic();
+      return FE;
+    }
+  }
+  
+  // Otherwise, didn't find it.
+  return 0;
+}
+
+/// LookupSubframeworkHeader - 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 *HeaderSearch::
+LookupSubframeworkHeader(const char *FilenameStart,
+                         const char *FilenameEnd,
+                         const FileEntry *ContextFileEnt) {
+  // Framework names must have a '/' in the filename.  Find it.
+  const char *SlashPos = std::find(FilenameStart, FilenameEnd, '/');
+  if (SlashPos == FilenameEnd) return 0;
+  
+  // Look up the base framework name of the ContextFileEnt.
+  const char *ContextName = ContextFileEnt->getName();
+    
+  // If the context info wasn't a framework, couldn't be a subframework.
+  const char *FrameworkPos = strstr(ContextName, ".framework/");
+  if (FrameworkPos == 0)
+    return 0;
+  
+  llvm::SmallString<1024> FrameworkName(ContextName, 
+                                        FrameworkPos+strlen(".framework/"));
+
+  // Append Frameworks/HIToolbox.framework/
+  FrameworkName += "Frameworks/";
+  FrameworkName.append(FilenameStart, SlashPos);
+  FrameworkName += ".framework/";
+
+  llvm::StringMapEntry<const DirectoryEntry *> &CacheLookup =
+    FrameworkMap.GetOrCreateValue(FilenameStart, SlashPos);
+  
+  // Some other location?
+  if (CacheLookup.getValue() &&
+      CacheLookup.getKeyLength() == FrameworkName.size() &&
+      memcmp(CacheLookup.getKeyData(), &FrameworkName[0],
+             CacheLookup.getKeyLength()) != 0)
+    return 0;
+  
+  // Cache subframework.
+  if (CacheLookup.getValue() == 0) {
+    ++NumSubFrameworkLookups;
+    
+    // If the framework dir doesn't exist, we fail.
+    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.begin(),
+                                                     FrameworkName.end());
+    if (Dir == 0) return 0;
+    
+    // Otherwise, if it does, remember that this is the right direntry for this
+    // framework.
+    CacheLookup.setValue(Dir);
+  }
+  
+  const FileEntry *FE = 0;
+
+  // Check ".../Frameworks/HIToolbox.framework/Headers/HIToolbox.h"
+  llvm::SmallString<1024> HeadersFilename(FrameworkName);
+  HeadersFilename += "Headers/";
+  HeadersFilename.append(SlashPos+1, FilenameEnd);
+  if (!(FE = FileMgr.getFile(HeadersFilename.begin(),
+                             HeadersFilename.end()))) {
+    
+    // Check ".../Frameworks/HIToolbox.framework/PrivateHeaders/HIToolbox.h"
+    HeadersFilename = FrameworkName;
+    HeadersFilename += "PrivateHeaders/";
+    HeadersFilename.append(SlashPos+1, FilenameEnd);
+    if (!(FE = FileMgr.getFile(HeadersFilename.begin(), HeadersFilename.end())))
+      return 0;
+  }
+  
+  // This file is a system header or C++ unfriendly if the old file is.
+  getFileInfo(FE).DirInfo = getFileInfo(ContextFileEnt).DirInfo;
+  return FE;
+}
+
+//===----------------------------------------------------------------------===//
+// File Info Management.
+//===----------------------------------------------------------------------===//
+
+
+/// getFileInfo - Return the PerFileInfo structure for the specified
+/// FileEntry.
+HeaderSearch::PerFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) {
+  if (FE->getUID() >= FileInfo.size())
+    FileInfo.resize(FE->getUID()+1);
+  return FileInfo[FE->getUID()];
+}  
+
+/// ShouldEnterIncludeFile - 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 HeaderSearch::ShouldEnterIncludeFile(const FileEntry *File, bool isImport){
+  ++NumIncluded; // Count # of attempted #includes.
+
+  // Get information about this file.
+  PerFileInfo &FileInfo = getFileInfo(File);
+  
+  // If this is a #import directive, check that we have not already imported
+  // this header.
+  if (isImport) {
+    // If this has already been imported, don't import it again.
+    FileInfo.isImport = true;
+    
+    // Has this already been #import'ed or #include'd?
+    if (FileInfo.NumIncludes) return false;
+  } else {
+    // Otherwise, if this is a #include of a file that was previously #import'd
+    // or if this is the second #include of a #pragma once file, ignore it.
+    if (FileInfo.isImport)
+      return false;
+  }
+  
+  // Next, check to see if the file is wrapped with #ifndef guards.  If so, and
+  // if the macro that guards it is defined, we know the #include has no effect.
+  if (FileInfo.ControllingMacro && FileInfo.ControllingMacro->getMacroInfo()) {
+    ++NumMultiIncludeFileOptzn;
+    return false;
+  }
+  
+  // Increment the number of times this file has been included.
+  ++FileInfo.NumIncludes;
+  
+  return true;
+}
+
+