Clang plugin that rewrites PostTask(_, NewRunnableMethod(...)) to PostTask(_, base::Bind(...));

tools/clang/BindMigrate/FileRemapper.cpp

+//===--- FileRemapper.cpp - File Remapping Helper -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "FileRemapper.h"
+#include "clang/Frontend/CompilerInvocation.h"
+#include "clang/Basic/FileManager.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/raw_ostream.h"
+#include <fstream>
+
+using namespace clang;
+using namespace arcmt_hack;
+
+FileRemapper::FileRemapper() {
+  FileMgr.reset(new FileManager(FileSystemOptions()));
+}
+
+FileRemapper::~FileRemapper() {
+  clear();
+}
+
+void FileRemapper::clear(StringRef outputDir) {
+  for (MappingsTy::iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I)
+    resetTarget(I->second);
+  FromToMappings.clear();
+  assert(ToFromMappings.empty());
+  if (!outputDir.empty()) {
+    std::string infoFile = getRemapInfoFile(outputDir);
+    bool existed;
+    llvm::sys::fs::remove(infoFile, existed);
+  }
+}
+
+std::string FileRemapper::getRemapInfoFile(StringRef outputDir) {
+  assert(!outputDir.empty());
+  llvm::sys::Path dir(outputDir);
+  llvm::sys::Path infoFile = dir;
+  infoFile.appendComponent("remap");
+  return infoFile.str();
+}
+
+bool FileRemapper::initFromDisk(StringRef outputDir, Diagnostic &Diag,
+                                bool ignoreIfFilesChanged) {
+  assert(FromToMappings.empty() &&
+         "initFromDisk should be called before any remap calls");
+  std::string infoFile = getRemapInfoFile(outputDir);
+  bool fileExists = false;
+  llvm::sys::fs::exists(infoFile, fileExists);
+  if (!fileExists)
+    return false;
+
+  std::vector<std::pair<const FileEntry *, const FileEntry *> > pairs;
+  
+  llvm::OwningPtr<llvm::MemoryBuffer> fileBuf;
+  if (llvm::error_code ec = llvm::MemoryBuffer::getFile(infoFile.c_str(),
+                                                        fileBuf))
+    return report("Error opening file: " + infoFile, Diag);
+  
+  SmallVector<StringRef, 64> lines;
+  fileBuf->getBuffer().split(lines, "\n");
+
+  for (unsigned idx = 0; idx+3 <= lines.size(); idx += 3) {
+    StringRef fromFilename = lines[idx];
+    unsigned long long timeModified;
+    lines[idx+1].getAsInteger(10, timeModified);
+    StringRef toFilename = lines[idx+2];
+    
+    const FileEntry *origFE = FileMgr->getFile(fromFilename);
+    if (!origFE) {
+      if (ignoreIfFilesChanged)
+        continue;
+      return report("File does not exist: " + fromFilename, Diag);
+    }
+    const FileEntry *newFE = FileMgr->getFile(toFilename);
+    if (!newFE) {
+      if (ignoreIfFilesChanged)
+        continue;
+      return report("File does not exist: " + toFilename, Diag);
+    }
+
+    if ((uint64_t)origFE->getModificationTime() != timeModified) {
+      if (ignoreIfFilesChanged)
+        continue;
+      return report("File was modified: " + fromFilename, Diag);
+    }
+
+    pairs.push_back(std::make_pair(origFE, newFE));
+  }
+
+  for (unsigned i = 0, e = pairs.size(); i != e; ++i)
+    remap(pairs[i].first, pairs[i].second);
+
+  return false;
+}
+
+bool FileRemapper::flushToDisk(StringRef outputDir, Diagnostic &Diag) {
+  using namespace llvm::sys;
+
+  bool existed;
+  if (fs::create_directory(outputDir, existed) != llvm::errc::success)
+    return report("Could not create directory: " + outputDir, Diag);
+
+  std::string errMsg;
+  std::string infoFile = getRemapInfoFile(outputDir);
+  llvm::raw_fd_ostream infoOut(infoFile.c_str(), errMsg,
+                               llvm::raw_fd_ostream::F_Binary);
+  if (!errMsg.empty())
+    return report(errMsg, Diag);
+
+  for (MappingsTy::iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I) {
+
+    const FileEntry *origFE = I->first;
+    llvm::SmallString<200> origPath = StringRef(origFE->getName());
+    fs::make_absolute(origPath);
+    infoOut << origPath << '\n';
+    infoOut << (uint64_t)origFE->getModificationTime() << '\n';
+
+    if (const FileEntry *FE = I->second.dyn_cast<const FileEntry *>()) {
+      llvm::SmallString<200> newPath = StringRef(FE->getName());
+      fs::make_absolute(newPath);
+      infoOut << newPath << '\n';
+    } else {
+
+      llvm::SmallString<64> tempPath;
+      tempPath = path::filename(origFE->getName());
+      tempPath += "-%%%%%%%%";
+      tempPath += path::extension(origFE->getName());
+      int fd;
+      if (fs::unique_file(tempPath.str(), fd, tempPath) != llvm::errc::success)
+        return report("Could not create file: " + tempPath.str(), Diag);
+
+      llvm::raw_fd_ostream newOut(fd, /*shouldClose=*/true);
+      llvm::MemoryBuffer *mem = I->second.get<llvm::MemoryBuffer *>();
+      newOut.write(mem->getBufferStart(), mem->getBufferSize());
+      newOut.close();
+      
+      const FileEntry *newE = FileMgr->getFile(tempPath);
+      remap(origFE, newE);
+      infoOut << newE->getName() << '\n';
+    }
+  }
+
+  infoOut.close();
+  return false;
+}
+
+bool FileRemapper::overwriteOriginal(Diagnostic &Diag,
+                                     StringRef outputDir) {
+  using namespace llvm::sys;
+
+  for (MappingsTy::iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I) {
+    const FileEntry *origFE = I->first;
+    if (const FileEntry *newFE = I->second.dyn_cast<const FileEntry *>()) {
+      if (fs::copy_file(newFE->getName(), origFE->getName(),
+                 fs::copy_option::overwrite_if_exists) != llvm::errc::success)
+        return report(StringRef("Could not copy file '") + newFE->getName() +
+                      "' to file '" + origFE->getName() + "'", Diag);
+    } else {
+
+      bool fileExists = false;
+      fs::exists(origFE->getName(), fileExists);
+      if (!fileExists)
+        return report(StringRef("File does not exist: ") + origFE->getName(),
+                      Diag);
+
+      std::string errMsg;
+      llvm::raw_fd_ostream Out(origFE->getName(), errMsg,
+                               llvm::raw_fd_ostream::F_Binary);
+      if (!errMsg.empty())
+        return report(errMsg, Diag);
+
+      llvm::MemoryBuffer *mem = I->second.get<llvm::MemoryBuffer *>();
+      Out.write(mem->getBufferStart(), mem->getBufferSize());
+      Out.close();
+    }
+  }
+
+  clear(outputDir);
+  return false;
+}
+
+bool FileRemapper::writeParallelTree(StringRef outputDir,
+                                     Diagnostic &Diag) {
+  using namespace llvm::sys;
+  bool existed;
+
+  for (MappingsTy::iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I) {
+    const FileEntry *origFE = I->first;
+    std::string new_name = outputDir.str() + origFE->getName();
+    StringRef directory = path::parent_path(new_name);
+    if (fs::create_directories(directory, existed) != llvm::errc::success)
+      return report("Could not create directory: " + directory, Diag);
+    if (const FileEntry *newFE = I->second.dyn_cast<const FileEntry *>()) {
+      if (fs::copy_file(newFE->getName(), new_name.c_str(),
+                 fs::copy_option::overwrite_if_exists) != llvm::errc::success)
+        return report(StringRef("Could not copy file '") + newFE->getName() +
+                      "' to file '" + new_name + "'", Diag);
+    } else {
+      std::string errMsg;
+      llvm::raw_fd_ostream Out(new_name.c_str(), errMsg,
+                               llvm::raw_fd_ostream::F_Binary);
+      if (!errMsg.empty())
+        return report(errMsg, Diag);
+
+      llvm::MemoryBuffer *mem = I->second.get<llvm::MemoryBuffer *>();
+      Out.write(mem->getBufferStart(), mem->getBufferSize());
+      Out.close();
+    }
+  }
+
+  return false;
+}
+
+void FileRemapper::applyMappings(CompilerInvocation &CI) const {
+  PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
+  for (MappingsTy::const_iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I) {
+    if (const FileEntry *FE = I->second.dyn_cast<const FileEntry *>()) {
+      PPOpts.addRemappedFile(I->first->getName(), FE->getName());
+    } else {
+      llvm::MemoryBuffer *mem = I->second.get<llvm::MemoryBuffer *>();
+      PPOpts.addRemappedFile(I->first->getName(), mem);
+    }
+  }
+
+  PPOpts.RetainRemappedFileBuffers = true;
+}
+
+void FileRemapper::transferMappingsAndClear(CompilerInvocation &CI) {
+  PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
+  for (MappingsTy::iterator
+         I = FromToMappings.begin(), E = FromToMappings.end(); I != E; ++I) {
+    if (const FileEntry *FE = I->second.dyn_cast<const FileEntry *>()) {
+      PPOpts.addRemappedFile(I->first->getName(), FE->getName());
+    } else {
+      llvm::MemoryBuffer *mem = I->second.get<llvm::MemoryBuffer *>();
+      PPOpts.addRemappedFile(I->first->getName(), mem);
+    }
+    I->second = Target();
+  }
+
+  PPOpts.RetainRemappedFileBuffers = false;
+  clear();
+}
+
+void FileRemapper::remap(StringRef filePath, llvm::MemoryBuffer *memBuf) {
+  remap(getOriginalFile(filePath), memBuf);
+}
+
+void FileRemapper::remap(StringRef filePath, StringRef newPath) {
+  const FileEntry *file = getOriginalFile(filePath);
+  const FileEntry *newfile = FileMgr->getFile(newPath);
+  remap(file, newfile);
+}
+
+void FileRemapper::remap(const FileEntry *file, llvm::MemoryBuffer *memBuf) {
+  assert(file);
+  Target &targ = FromToMappings[file];
+  resetTarget(targ);
+  targ = memBuf;
+}
+
+void FileRemapper::remap(const FileEntry *file, const FileEntry *newfile) {
+  assert(file && newfile);
+  Target &targ = FromToMappings[file];
+  resetTarget(targ);
+  targ = newfile;
+  ToFromMappings[newfile] = file;
+}
+
+const FileEntry *FileRemapper::getOriginalFile(StringRef filePath) {
+  const FileEntry *file = FileMgr->getFile(filePath);
+  // If we are updating a file that overriden an original file,
+  // actually update the original file.
+  llvm::DenseMap<const FileEntry *, const FileEntry *>::iterator
+    I = ToFromMappings.find(file);
+  if (I != ToFromMappings.end()) {
+    file = I->second;
+    assert(FromToMappings.find(file) != FromToMappings.end() &&
+           "Original file not in mappings!");
+  }
+  return file;
+}
+
+void FileRemapper::resetTarget(Target &targ) {
+  if (!targ)
+    return;
+
+  if (llvm::MemoryBuffer *oldmem = targ.dyn_cast<llvm::MemoryBuffer *>()) {
+    delete oldmem;
+  } else {
+    const FileEntry *toFE = targ.get<const FileEntry *>();
+    llvm::DenseMap<const FileEntry *, const FileEntry *>::iterator
+      I = ToFromMappings.find(toFE);
+    if (I != ToFromMappings.end())
+      ToFromMappings.erase(I);
+  }
+}
+
+bool FileRemapper::report(const Twine &err, Diagnostic &Diag) {
+  llvm::SmallString<128> buf;
+  unsigned ID = Diag.getDiagnosticIDs()->getCustomDiagID(DiagnosticIDs::Error,
+                                                         err.toStringRef(buf));
+  Diag.Report(ID);
+  return true;
+}