Import ClangFormat.cpp from ^/vendor/clang/clang-release_380-r262564

Discussed with:	dim
Approved by:	re (gjb)

1 files changed, 364 insertions, 0 deletions

diff --git a/contrib/llvm/tools/clang/tools/clang-format/ClangFormat.cpp b/contrib/llvm/tools/clang/tools/clang-format/ClangFormat.cpp
new file mode 100644
index 000000000000..36f237fc750c
--- /dev/null
+++ b/contrib/llvm/tools/clang/tools/clang-format/ClangFormat.cpp
@@ -0,0 +1,364 @@
+//===-- clang-format/ClangFormat.cpp - Clang format tool ------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file implements a clang-format tool that automatically formats
+/// (fragments of) C++ code.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Basic/Version.h"
+#include "clang/Format/Format.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Signals.h"
+
+using namespace llvm;
+using clang::tooling::Replacements;
+
+static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
+
+// Mark all our options with this category, everything else (except for -version
+// and -help) will be hidden.
+static cl::OptionCategory ClangFormatCategory("Clang-format options");
+
+static cl::list<unsigned>
+    Offsets("offset",
+            cl::desc("Format a range starting at this byte offset.\n"
+                     "Multiple ranges can be formatted by specifying\n"
+                     "several -offset and -length pairs.\n"
+                     "Can only be used with one input file."),
+            cl::cat(ClangFormatCategory));
+static cl::list<unsigned>
+    Lengths("length",
+            cl::desc("Format a range of this length (in bytes).\n"
+                     "Multiple ranges can be formatted by specifying\n"
+                     "several -offset and -length pairs.\n"
+                     "When only a single -offset is specified without\n"
+                     "-length, clang-format will format up to the end\n"
+                     "of the file.\n"
+                     "Can only be used with one input file."),
+            cl::cat(ClangFormatCategory));
+static cl::list<std::string>
+LineRanges("lines", cl::desc("<start line>:<end line> - format a range of\n"
+                             "lines (both 1-based).\n"
+                             "Multiple ranges can be formatted by specifying\n"
+                             "several -lines arguments.\n"
+                             "Can't be used with -offset and -length.\n"
+                             "Can only be used with one input file."),
+           cl::cat(ClangFormatCategory));
+static cl::opt<std::string>
+    Style("style",
+          cl::desc(clang::format::StyleOptionHelpDescription),
+          cl::init("file"), cl::cat(ClangFormatCategory));
+static cl::opt<std::string>
+FallbackStyle("fallback-style",
+              cl::desc("The name of the predefined style used as a\n"
+                       "fallback in case clang-format is invoked with\n"
+                       "-style=file, but can not find the .clang-format\n"
+                       "file to use.\n"
+                       "Use -fallback-style=none to skip formatting."),
+              cl::init("LLVM"), cl::cat(ClangFormatCategory));
+
+static cl::opt<std::string>
+AssumeFileName("assume-filename",
+               cl::desc("When reading from stdin, clang-format assumes this\n"
+                        "filename to look for a style config file (with\n"
+                        "-style=file) and to determine the language."),
+               cl::init("<stdin>"), cl::cat(ClangFormatCategory));
+
+static cl::opt<bool> Inplace("i",
+                             cl::desc("Inplace edit <file>s, if specified."),
+                             cl::cat(ClangFormatCategory));
+
+static cl::opt<bool> OutputXML("output-replacements-xml",
+                               cl::desc("Output replacements as XML."),
+                               cl::cat(ClangFormatCategory));
+static cl::opt<bool>
+    DumpConfig("dump-config",
+               cl::desc("Dump configuration options to stdout and exit.\n"
+                        "Can be used with -style option."),
+               cl::cat(ClangFormatCategory));
+static cl::opt<unsigned>
+    Cursor("cursor",
+           cl::desc("The position of the cursor when invoking\n"
+                    "clang-format from an editor integration"),
+           cl::init(0), cl::cat(ClangFormatCategory));
+
+static cl::opt<bool> SortIncludes(
+    "sort-includes",
+    cl::desc("If set, overrides the include sorting behavior determined by the "
+             "SortIncludes style flag"),
+    cl::cat(ClangFormatCategory));
+
+static cl::list<std::string> FileNames(cl::Positional, cl::desc("[<file> ...]"),
+                                       cl::cat(ClangFormatCategory));
+
+namespace clang {
+namespace format {
+
+static FileID createInMemoryFile(StringRef FileName, MemoryBuffer *Source,
+                                 SourceManager &Sources, FileManager &Files,
+                                 vfs::InMemoryFileSystem *MemFS) {
+  MemFS->addFileNoOwn(FileName, 0, Source);
+  return Sources.createFileID(Files.getFile(FileName), SourceLocation(),
+                              SrcMgr::C_User);
+}
+
+// Parses <start line>:<end line> input to a pair of line numbers.
+// Returns true on error.
+static bool parseLineRange(StringRef Input, unsigned &FromLine,
+                           unsigned &ToLine) {
+  std::pair<StringRef, StringRef> LineRange = Input.split(':');
+  return LineRange.first.getAsInteger(0, FromLine) ||
+         LineRange.second.getAsInteger(0, ToLine);
+}
+
+static bool fillRanges(MemoryBuffer *Code,
+                       std::vector<tooling::Range> &Ranges) {
+  IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
+      new vfs::InMemoryFileSystem);
+  FileManager Files(FileSystemOptions(), InMemoryFileSystem);
+  DiagnosticsEngine Diagnostics(
+      IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs),
+      new DiagnosticOptions);
+  SourceManager Sources(Diagnostics, Files);
+  FileID ID = createInMemoryFile("<irrelevant>", Code, Sources, Files,
+                                 InMemoryFileSystem.get());
+  if (!LineRanges.empty()) {
+    if (!Offsets.empty() || !Lengths.empty()) {
+      errs() << "error: cannot use -lines with -offset/-length\n";
+      return true;
+    }
+
+    for (unsigned i = 0, e = LineRanges.size(); i < e; ++i) {
+      unsigned FromLine, ToLine;
+      if (parseLineRange(LineRanges[i], FromLine, ToLine)) {
+        errs() << "error: invalid <start line>:<end line> pair\n";
+        return true;
+      }
+      if (FromLine > ToLine) {
+        errs() << "error: start line should be less than end line\n";
+        return true;
+      }
+      SourceLocation Start = Sources.translateLineCol(ID, FromLine, 1);
+      SourceLocation End = Sources.translateLineCol(ID, ToLine, UINT_MAX);
+      if (Start.isInvalid() || End.isInvalid())
+        return true;
+      unsigned Offset = Sources.getFileOffset(Start);
+      unsigned Length = Sources.getFileOffset(End) - Offset;
+      Ranges.push_back(tooling::Range(Offset, Length));
+    }
+    return false;
+  }
+
+  if (Offsets.empty())
+    Offsets.push_back(0);
+  if (Offsets.size() != Lengths.size() &&
+      !(Offsets.size() == 1 && Lengths.empty())) {
+    errs() << "error: number of -offset and -length arguments must match.\n";
+    return true;
+  }
+  for (unsigned i = 0, e = Offsets.size(); i != e; ++i) {
+    if (Offsets[i] >= Code->getBufferSize()) {
+      errs() << "error: offset " << Offsets[i] << " is outside the file\n";
+      return true;
+    }
+    SourceLocation Start =
+        Sources.getLocForStartOfFile(ID).getLocWithOffset(Offsets[i]);
+    SourceLocation End;
+    if (i < Lengths.size()) {
+      if (Offsets[i] + Lengths[i] > Code->getBufferSize()) {
+        errs() << "error: invalid length " << Lengths[i]
+               << ", offset + length (" << Offsets[i] + Lengths[i]
+               << ") is outside the file.\n";
+        return true;
+      }
+      End = Start.getLocWithOffset(Lengths[i]);
+    } else {
+      End = Sources.getLocForEndOfFile(ID);
+    }
+    unsigned Offset = Sources.getFileOffset(Start);
+    unsigned Length = Sources.getFileOffset(End) - Offset;
+    Ranges.push_back(tooling::Range(Offset, Length));
+  }
+  return false;
+}
+
+static void outputReplacementXML(StringRef Text) {
+  // FIXME: When we sort includes, we need to make sure the stream is correct
+  // utf-8.
+  size_t From = 0;
+  size_t Index;
+  while ((Index = Text.find_first_of("\n\r<&", From)) != StringRef::npos) {
+    outs() << Text.substr(From, Index - From);
+    switch (Text[Index]) {
+    case '\n':
+      outs() << "&#10;";
+      break;
+    case '\r':
+      outs() << "&#13;";
+      break;
+    case '<':
+      outs() << "&lt;";
+      break;
+    case '&':
+      outs() << "&amp;";
+      break;
+    default:
+      llvm_unreachable("Unexpected character encountered!");
+    }
+    From = Index + 1;
+  }
+  outs() << Text.substr(From);
+}
+
+static void outputReplacementsXML(const Replacements &Replaces) {
+  for (const auto &R : Replaces) {
+    outs() << "<replacement "
+           << "offset='" << R.getOffset() << "' "
+           << "length='" << R.getLength() << "'>";
+    outputReplacementXML(R.getReplacementText());
+    outs() << "</replacement>\n";
+  }
+}
+
+// Returns true on error.
+static bool format(StringRef FileName) {
+  ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
+      MemoryBuffer::getFileOrSTDIN(FileName);
+  if (std::error_code EC = CodeOrErr.getError()) {
+    errs() << EC.message() << "\n";
+    return true;
+  }
+  std::unique_ptr<llvm::MemoryBuffer> Code = std::move(CodeOrErr.get());
+  if (Code->getBufferSize() == 0)
+    return false; // Empty files are formatted correctly.
+  std::vector<tooling::Range> Ranges;
+  if (fillRanges(Code.get(), Ranges))
+    return true;
+  StringRef AssumedFileName = (FileName == "-") ? AssumeFileName : FileName;
+  FormatStyle FormatStyle = getStyle(Style, AssumedFileName, FallbackStyle);
+  if (SortIncludes.getNumOccurrences() != 0)
+    FormatStyle.SortIncludes = SortIncludes;
+  unsigned CursorPosition = Cursor;
+  Replacements Replaces = sortIncludes(FormatStyle, Code->getBuffer(), Ranges,
+                                       AssumedFileName, &CursorPosition);
+  std::string ChangedCode =
+      tooling::applyAllReplacements(Code->getBuffer(), Replaces);
+  for (const auto &R : Replaces)
+    Ranges.push_back({R.getOffset(), R.getLength()});
+
+  bool IncompleteFormat = false;
+  Replacements FormatChanges = reformat(FormatStyle, ChangedCode, Ranges,
+                                        AssumedFileName, &IncompleteFormat);
+  Replaces = tooling::mergeReplacements(Replaces, FormatChanges);
+  if (OutputXML) {
+    outs() << "<?xml version='1.0'?>\n<replacements "
+              "xml:space='preserve' incomplete_format='"
+           << (IncompleteFormat ? "true" : "false") << "'>\n";
+    if (Cursor.getNumOccurrences() != 0)
+      outs() << "<cursor>"
+             << tooling::shiftedCodePosition(FormatChanges, CursorPosition)
+             << "</cursor>\n";
+
+    outputReplacementsXML(Replaces); 
+    outs() << "</replacements>\n";
+  } else {
+    IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
+        new vfs::InMemoryFileSystem);
+    FileManager Files(FileSystemOptions(), InMemoryFileSystem);
+    DiagnosticsEngine Diagnostics(
+        IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs),
+        new DiagnosticOptions);
+    SourceManager Sources(Diagnostics, Files);
+    FileID ID = createInMemoryFile(AssumedFileName, Code.get(), Sources, Files,
+                                   InMemoryFileSystem.get());
+    Rewriter Rewrite(Sources, LangOptions());
+    tooling::applyAllReplacements(Replaces, Rewrite);
+    if (Inplace) {
+      if (FileName == "-")
+        errs() << "error: cannot use -i when reading from stdin.\n";
+      else if (Rewrite.overwriteChangedFiles())
+        return true;
+    } else {
+      if (Cursor.getNumOccurrences() != 0)
+        outs() << "{ \"Cursor\": "
+               << tooling::shiftedCodePosition(FormatChanges, CursorPosition)
+               << ", \"IncompleteFormat\": "
+               << (IncompleteFormat ? "true" : "false") << " }\n";
+      Rewrite.getEditBuffer(ID).write(outs());
+    }
+  }
+  return false;
+}
+
+}  // namespace format
+}  // namespace clang
+
+static void PrintVersion() {
+  raw_ostream &OS = outs();
+  OS << clang::getClangToolFullVersion("clang-format") << '\n';
+}
+
+int main(int argc, const char **argv) {
+  llvm::sys::PrintStackTraceOnErrorSignal();
+
+  cl::HideUnrelatedOptions(ClangFormatCategory);
+
+  cl::SetVersionPrinter(PrintVersion);
+  cl::ParseCommandLineOptions(
+      argc, argv,
+      "A tool to format C/C++/Java/JavaScript/Objective-C/Protobuf code.\n\n"
+      "If no arguments are specified, it formats the code from standard input\n"
+      "and writes the result to the standard output.\n"
+      "If <file>s are given, it reformats the files. If -i is specified\n"
+      "together with <file>s, the files are edited in-place. Otherwise, the\n"
+      "result is written to the standard output.\n");
+
+  if (Help)
+    cl::PrintHelpMessage();
+
+  if (DumpConfig) {
+    std::string Config =
+        clang::format::configurationAsText(clang::format::getStyle(
+            Style, FileNames.empty() ? AssumeFileName : FileNames[0],
+            FallbackStyle));
+    outs() << Config << "\n";
+    return 0;
+  }
+
+  bool Error = false;
+  switch (FileNames.size()) {
+  case 0:
+    Error = clang::format::format("-");
+    break;
+  case 1:
+    Error = clang::format::format(FileNames[0]);
+    break;
+  default:
+    if (!Offsets.empty() || !Lengths.empty() || !LineRanges.empty()) {
+      errs() << "error: -offset, -length and -lines can only be used for "
+                "single file.\n";
+      return 1;
+    }
+    for (unsigned i = 0; i < FileNames.size(); ++i)
+      Error |= clang::format::format(FileNames[i]);
+    break;
+  }
+  return Error ? 1 : 0;
+}
+