llvm/Support/WithColor.h

0001 //===- WithColor.h ----------------------------------------------*- C++ -*-===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef LLVM_SUPPORT_WITHCOLOR_H
0010 #define LLVM_SUPPORT_WITHCOLOR_H
0011
0012 #include "llvm/Support/Compiler.h"
0013 #include "llvm/Support/raw_ostream.h"
0014
0015 namespace llvm {
0016
0017 class Error;
0018 class StringRef;
0019
0020 namespace cl {
0021 class OptionCategory;
0022 }
0023
0024 extern cl::OptionCategory &getColorCategory();
0025
0026 // Symbolic names for various syntax elements.
0027 enum class HighlightColor {
0028   Address,
0029   String,
0030   Tag,
0031   Attribute,
0032   Enumerator,
0033   Macro,
0034   Error,
0035   Warning,
0036   Note,
0037   Remark
0038 };
0039
0040 enum class ColorMode {
0041   /// Determine whether to use color based on the command line argument and the
0042   /// raw_ostream.
0043   Auto,
0044   /// Enable colors. Because raw_ostream is the one implementing colors, this
0045   /// has no effect if the stream does not support colors or has colors
0046   /// disabled.
0047   Enable,
0048   /// Disable colors.
0049   Disable,
0050 };
0051
0052 /// An RAII object that temporarily switches an output stream to a specific
0053 /// color.
0054 class WithColor {
0055 public:
0056   using AutoDetectFunctionType = bool (*)(const raw_ostream &OS);
0057
0058   /// To be used like this: WithColor(OS, HighlightColor::String) << "text";
0059   /// @param OS The output stream
0060   /// @param S Symbolic name for syntax element to color
0061   /// @param Mode Enable, disable or compute whether to use colors.
0062   LLVM_CTOR_NODISCARD WithColor(raw_ostream &OS, HighlightColor S,
0063                                 ColorMode Mode = ColorMode::Auto);
0064   /// To be used like this: WithColor(OS, raw_ostream::BLACK) << "text";
0065   /// @param OS The output stream
0066   /// @param Color ANSI color to use, the special SAVEDCOLOR can be used to
0067   /// change only the bold attribute, and keep colors untouched
0068   /// @param Bold Bold/brighter text, default false
0069   /// @param BG If true, change the background, default: change foreground
0070   /// @param Mode Enable, disable or compute whether to use colors.
0071   LLVM_CTOR_NODISCARD WithColor(
0072       raw_ostream &OS, raw_ostream::Colors Color = raw_ostream::SAVEDCOLOR,
0073       bool Bold = false, bool BG = false, ColorMode Mode = ColorMode::Auto)
0074       : OS(OS), Mode(Mode) {
0075     changeColor(Color, Bold, BG);
0076   }
0077   ~WithColor();
0078
0079   raw_ostream &get() { return OS; }
0080   operator raw_ostream &() { return OS; }
0081   template <typename T> WithColor &operator<<(T &O) {
0082     OS << O;
0083     return *this;
0084   }
0085   template <typename T> WithColor &operator<<(const T &O) {
0086     OS << O;
0087     return *this;
0088   }
0089
0090   /// Convenience method for printing "error: " to stderr.
0091   static raw_ostream &error();
0092   /// Convenience method for printing "warning: " to stderr.
0093   static raw_ostream &warning();
0094   /// Convenience method for printing "note: " to stderr.
0095   static raw_ostream &note();
0096   /// Convenience method for printing "remark: " to stderr.
0097   static raw_ostream &remark();
0098
0099   /// Convenience method for printing "error: " to the given stream.
0100   static raw_ostream &error(raw_ostream &OS, StringRef Prefix = "",
0101                             bool DisableColors = false);
0102   /// Convenience method for printing "warning: " to the given stream.
0103   static raw_ostream &warning(raw_ostream &OS, StringRef Prefix = "",
0104                               bool DisableColors = false);
0105   /// Convenience method for printing "note: " to the given stream.
0106   static raw_ostream &note(raw_ostream &OS, StringRef Prefix = "",
0107                            bool DisableColors = false);
0108   /// Convenience method for printing "remark: " to the given stream.
0109   static raw_ostream &remark(raw_ostream &OS, StringRef Prefix = "",
0110                              bool DisableColors = false);
0111
0112   /// Determine whether colors are displayed.
0113   bool colorsEnabled();
0114
0115   /// Change the color of text that will be output from this point forward.
0116   /// @param Color ANSI color to use, the special SAVEDCOLOR can be used to
0117   /// change only the bold attribute, and keep colors untouched
0118   /// @param Bold Bold/brighter text, default false
0119   /// @param BG If true, change the background, default: change foreground
0120   WithColor &changeColor(raw_ostream::Colors Color, bool Bold = false,
0121                          bool BG = false);
0122
0123   /// Reset the colors to terminal defaults. Call this when you are done
0124   /// outputting colored text, or before program exit.
0125   WithColor &resetColor();
0126
0127   /// Implement default handling for Error.
0128   /// Print "error: " to stderr.
0129   static void defaultErrorHandler(Error Err);
0130
0131   /// Implement default handling for Warning.
0132   /// Print "warning: " to stderr.
0133   static void defaultWarningHandler(Error Warning);
0134
0135   /// Retrieve the default color auto detection function.
0136   static AutoDetectFunctionType defaultAutoDetectFunction();
0137
0138   /// Change the global auto detection function.
0139   static void
0140   setAutoDetectFunction(AutoDetectFunctionType NewAutoDetectFunction);
0141
0142 private:
0143   raw_ostream &OS;
0144   ColorMode Mode;
0145
0146   static AutoDetectFunctionType AutoDetectFunction;
0147 };
0148
0149 } // end namespace llvm
0150
0151 #endif // LLVM_SUPPORT_WITHCOLOR_H