Add the clang library to the repo (with some of my changes, too).

1 files changed, 178 insertions, 0 deletions

diff --git a/clang/lib/Frontend/TextDiagnosticPrinter.cpp b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
new file mode 100644
index 0000000..6445a0c
--- /dev/null
+++ b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
@@ -0,0 +1,178 @@
+//===--- TextDiagnosticPrinter.cpp - Diagnostic Printer -------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This diagnostic client prints out their diagnostic messages.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/TextDiagnosticPrinter.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/DiagnosticOptions.h"
+#include "clang/Frontend/TextDiagnostic.h"
+#include "clang/Lex/Lexer.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/SmallString.h"
+#include <algorithm>
+using namespace clang;
+
+TextDiagnosticPrinter::TextDiagnosticPrinter(raw_ostream &os,
+                                             const DiagnosticOptions &diags,
+                                             bool _OwnsOutputStream)
+  : OS(os), LangOpts(0), DiagOpts(&diags), SM(0),
+    OwnsOutputStream(_OwnsOutputStream) {
+}
+
+TextDiagnosticPrinter::~TextDiagnosticPrinter() {
+  if (OwnsOutputStream)
+    delete &OS;
+}
+
+void TextDiagnosticPrinter::BeginSourceFile(const LangOptions &LO,
+                                            const Preprocessor *PP) {
+  LangOpts = &LO;
+}
+
+void TextDiagnosticPrinter::EndSourceFile() {
+  LangOpts = 0;
+  TextDiag.reset(0);
+}
+
+/// \brief Print any diagnostic option information to a raw_ostream.
+///
+/// This implements all of the logic for adding diagnostic options to a message
+/// (via OS). Each relevant option is comma separated and all are enclosed in
+/// the standard bracketing: " [...]".
+static void printDiagnosticOptions(raw_ostream &OS,
+                                   DiagnosticsEngine::Level Level,
+                                   const Diagnostic &Info,
+                                   const DiagnosticOptions &DiagOpts) {
+  bool Started = false;
+  if (DiagOpts.ShowOptionNames) {
+    // Handle special cases for non-warnings early.
+    if (Info.getID() == diag::fatal_too_many_errors) {
+      OS << " [-ferror-limit=]";
+      return;
+    }
+
+    // The code below is somewhat fragile because we are essentially trying to
+    // report to the user what happened by inferring what the diagnostic engine
+    // did. Eventually it might make more sense to have the diagnostic engine
+    // include some "why" information in the diagnostic.
+
+    // If this is a warning which has been mapped to an error by the user (as
+    // inferred by checking whether the default mapping is to an error) then
+    // flag it as such. Note that diagnostics could also have been mapped by a
+    // pragma, but we don't currently have a way to distinguish this.
+    if (Level == DiagnosticsEngine::Error &&
+        DiagnosticIDs::isBuiltinWarningOrExtension(Info.getID()) &&
+        !DiagnosticIDs::isDefaultMappingAsError(Info.getID())) {
+      OS << " [-Werror";
+      Started = true;
+    }
+
+    // If the diagnostic is an extension diagnostic and not enabled by default
+    // then it must have been turned on with -pedantic.
+    bool EnabledByDefault;
+    if (DiagnosticIDs::isBuiltinExtensionDiag(Info.getID(),
+                                              EnabledByDefault) &&
+        !EnabledByDefault) {
+      OS << (Started ? "," : " [") << "-pedantic";
+      Started = true;
+    }
+
+    StringRef Opt = DiagnosticIDs::getWarningOptionForDiag(Info.getID());
+    if (!Opt.empty()) {
+      OS << (Started ? "," : " [") << "-W" << Opt;
+      Started = true;
+    }
+  }
+
+  // If the user wants to see category information, include it too.
+  if (DiagOpts.ShowCategories) {
+    unsigned DiagCategory =
+      DiagnosticIDs::getCategoryNumberForDiag(Info.getID());
+    if (DiagCategory) {
+      OS << (Started ? "," : " [");
+      Started = true;
+      if (DiagOpts.ShowCategories == 1)
+        OS << DiagCategory;
+      else {
+        assert(DiagOpts.ShowCategories == 2 && "Invalid ShowCategories value");
+        OS << DiagnosticIDs::getCategoryNameFromID(DiagCategory);
+      }
+    }
+  }
+  if (Started)
+    OS << ']';
+}
+
+void TextDiagnosticPrinter::HandleDiagnostic(DiagnosticsEngine::Level Level,
+                                             const Diagnostic &Info) {
+  // Default implementation (Warnings/errors count).
+  DiagnosticConsumer::HandleDiagnostic(Level, Info);
+
+  // Render the diagnostic message into a temporary buffer eagerly. We'll use
+  // this later as we print out the diagnostic to the terminal.
+  SmallString<100> OutStr;
+  Info.FormatDiagnostic(OutStr);
+
+  llvm::raw_svector_ostream DiagMessageStream(OutStr);
+  printDiagnosticOptions(DiagMessageStream, Level, Info, *DiagOpts);
+
+  // Keeps track of the the starting position of the location
+  // information (e.g., "foo.c:10:4:") that precedes the error
+  // message. We use this information to determine how long the
+  // file+line+column number prefix is.
+  uint64_t StartOfLocationInfo = OS.tell();
+
+  if (!Prefix.empty())
+    OS << Prefix << ": ";
+
+  // Use a dedicated, simpler path for diagnostics without a valid location.
+  // This is important as if the location is missing, we may be emitting
+  // diagnostics in a context that lacks language options, a source manager, or
+  // other infrastructure necessary when emitting more rich diagnostics.
+  if (!Info.getLocation().isValid()) {
+    TextDiagnostic::printDiagnosticLevel(OS, Level, DiagOpts->ShowColors);
+    TextDiagnostic::printDiagnosticMessage(OS, Level, DiagMessageStream.str(),
+                                           OS.tell() - StartOfLocationInfo,
+                                           DiagOpts->MessageLength,
+                                           DiagOpts->ShowColors);
+    OS.flush();
+    return;
+  }
+
+  // Assert that the rest of our infrastructure is setup properly.
+  assert(LangOpts && "Unexpected diagnostic outside source file processing");
+  assert(DiagOpts && "Unexpected diagnostic without options set");
+  assert(Info.hasSourceManager() &&
+         "Unexpected diagnostic with no source manager");
+
+  // Rebuild the TextDiagnostic utility if missing or the source manager has
+  // changed.
+  if (!TextDiag || SM != &Info.getSourceManager()) {
+    SM = &Info.getSourceManager();
+    TextDiag.reset(new TextDiagnostic(OS, *SM, *LangOpts, *DiagOpts));
+  }
+
+  TextDiag->emitDiagnostic(Info.getLocation(), Level, DiagMessageStream.str(),
+                           Info.getRanges(),
+                           llvm::makeArrayRef(Info.getFixItHints(),
+                                              Info.getNumFixItHints()));
+
+  OS.flush();
+}
+
+DiagnosticConsumer *
+TextDiagnosticPrinter::clone(DiagnosticsEngine &Diags) const {
+  return new TextDiagnosticPrinter(OS, *DiagOpts, /*OwnsOutputStream=*/false);
+}