//===--- TextDiagnosticPrinter.cpp - Diagnostic Printer -------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

// This diagnostic client prints out their diagnostic messages.

//

//===----------------------------------------------------------------------===//

#include "clang/Frontend/TextDiagnosticPrinter.h"

#include "clang/Basic/DiagnosticOptions.h"

#include "clang/Basic/SourceManager.h"

#include "clang/Frontend/TextDiagnostic.h"

#include "clang/Lex/Lexer.h"

#include "llvm/ADT/SmallString.h"

#include "llvm/Support/ErrorHandling.h"

#include "llvm/Support/raw_ostream.h"

#include <algorithm>

using namespace clang;

TextDiagnosticPrinter::TextDiagnosticPrinter(raw_ostream &os,

                                             DiagnosticOptions *diags,

                                             bool _OwnsOutputStream)

  : OS(os), DiagOpts(diags),

    OwnsOutputStream(_OwnsOutputStream) {

}

TextDiagnosticPrinter::~TextDiagnosticPrinter() {

  if (OwnsOutputStream)

    delete &OS;

}

void TextDiagnosticPrinter::BeginSourceFile(const LangOptions &LO,

                                            const Preprocessor *PP) {

  // Build the TextDiagnostic utility.

  TextDiag.reset(new TextDiagnostic(OS, LO, &*DiagOpts));

}

void TextDiagnosticPrinter::EndSourceFile() {

  TextDiag.reset();

}

/// 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;

    }

    StringRef Opt = DiagnosticIDs::getWarningOptionForDiag(Info.getID());

    if (!Opt.empty()) {

      OS << (Started ? "," : " [")

         << (Level == DiagnosticsEngine::Remark ? "-R" : "-W") << Opt;

      StringRef OptValue = Info.getDiags()->getFlagValue();

      if (!OptValue.empty())

        OS << "=" << OptValue;

      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 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, /*IsSupplemental=*/Level == DiagnosticsEngine::Note,

        DiagMessageStream.str(), OS.tell() - StartOfLocationInfo,

        DiagOpts->MessageLength, DiagOpts->ShowColors);

    OS.flush();

    return;

  }

  // Assert that the rest of our infrastructure is setup properly.

  assert(DiagOpts && "Unexpected diagnostic without options set");

  assert(Info.hasSourceManager() &&

         "Unexpected diagnostic with no source manager");

  assert(TextDiag && "Unexpected diagnostic outside source file processing");

  TextDiag->emitDiagnostic(

      FullSourceLoc(Info.getLocation(), Info.getSourceManager()), Level,

      DiagMessageStream.str(), Info.getRanges(), Info.getFixItHints());

  OS.flush();

}