AnsiTerminal.h

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//===---------------------AnsiTerminal.h ------------------------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
 
#ifndef LLDB_UTILITY_ANSITERMINAL_H
#define LLDB_UTILITY_ANSITERMINAL_H
 
#define ANSI_FG_COLOR_BLACK 30
#define ANSI_FG_COLOR_RED 31
#define ANSI_FG_COLOR_GREEN 32
#define ANSI_FG_COLOR_YELLOW 33
#define ANSI_FG_COLOR_BLUE 34
#define ANSI_FG_COLOR_PURPLE 35
#define ANSI_FG_COLOR_CYAN 36
#define ANSI_FG_COLOR_WHITE 37
 
#define ANSI_FG_COLOR_BRIGHT_BLACK 90
#define ANSI_FG_COLOR_BRIGHT_RED 91
#define ANSI_FG_COLOR_BRIGHT_GREEN 92
#define ANSI_FG_COLOR_BRIGHT_YELLOW 93
#define ANSI_FG_COLOR_BRIGHT_BLUE 94
#define ANSI_FG_COLOR_BRIGHT_PURPLE 95
#define ANSI_FG_COLOR_BRIGHT_CYAN 96
#define ANSI_FG_COLOR_BRIGHT_WHITE 97
 
#define ANSI_BG_COLOR_BLACK 40
#define ANSI_BG_COLOR_RED 41
#define ANSI_BG_COLOR_GREEN 42
#define ANSI_BG_COLOR_YELLOW 43
#define ANSI_BG_COLOR_BLUE 44
#define ANSI_BG_COLOR_PURPLE 45
#define ANSI_BG_COLOR_CYAN 46
#define ANSI_BG_COLOR_WHITE 47
 
#define ANSI_BG_COLOR_BRIGHT_BLACK 100
#define ANSI_BG_COLOR_BRIGHT_RED 101
#define ANSI_BG_COLOR_BRIGHT_GREEN 102
#define ANSI_BG_COLOR_BRIGHT_YELLOW 103
#define ANSI_BG_COLOR_BRIGHT_BLUE 104
#define ANSI_BG_COLOR_BRIGHT_PURPLE 105
#define ANSI_BG_COLOR_BRIGHT_CYAN 106
#define ANSI_BG_COLOR_BRIGHT_WHITE 107
 
#define ANSI_SPECIAL_FRAMED 51
#define ANSI_SPECIAL_ENCIRCLED 52
 
#define ANSI_CTRL_NORMAL 0
#define ANSI_CTRL_BOLD 1
#define ANSI_CTRL_FAINT 2
#define ANSI_CTRL_ITALIC 3
#define ANSI_CTRL_UNDERLINE 4
#define ANSI_CTRL_SLOW_BLINK 5
#define ANSI_CTRL_FAST_BLINK 6
#define ANSI_CTRL_IMAGE_NEGATIVE 7
#define ANSI_CTRL_CONCEAL 8
#define ANSI_CTRL_CROSSED_OUT 9
 
#define ANSI_ESC_START "\033["
#define ANSI_ESC_END "m"
 
#define ANSI_STR(s) #s
#define ANSI_DEF_STR(s) ANSI_STR(s)
 
#define ANSI_ESCAPE1(s) ANSI_ESC_START ANSI_DEF_STR(s) ANSI_ESC_END
 
#define ANSI_1_CTRL(ctrl1) "\033["##ctrl1 ANSI_ESC_END
#define ANSI_2_CTRL(ctrl1, ctrl2) "\033["##ctrl1 ";"##ctrl2 ANSI_ESC_END
 
#define ANSI_ESC_START_LEN 2
 
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Locale.h"
 
#include <string>
 
namespace lldb_private {
 
namespace ansi {
 
inline std::string FormatAnsiTerminalCodes(llvm::StringRef format,
                                           bool do_color = true) {
  // Convert "${ansi.XXX}" tokens to ansi values or clear them if do_color is
  // false.
  // clang-format off
  static const struct {
    const char *name;
    const char *value;
  } g_color_tokens[] = {
#define _TO_STR2(_val) #_val
#define _TO_STR(_val) _TO_STR2(_val)
      {"fg.black}",         ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BLACK) ANSI_ESC_END},
      {"fg.red}",           ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_RED) ANSI_ESC_END},
      {"fg.green}",         ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_GREEN) ANSI_ESC_END},
      {"fg.yellow}",        ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_YELLOW) ANSI_ESC_END},
      {"fg.blue}",          ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BLUE) ANSI_ESC_END},
      {"fg.purple}",        ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_PURPLE) ANSI_ESC_END},
      {"fg.cyan}",          ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_CYAN) ANSI_ESC_END},
      {"fg.white}",         ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_WHITE) ANSI_ESC_END},
      {"fg.bright.black}",  ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_BLACK) ANSI_ESC_END},
      {"fg.bright.red}",    ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_RED) ANSI_ESC_END},
      {"fg.bright.green}",  ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_GREEN) ANSI_ESC_END},
      {"fg.bright.yellow}", ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_YELLOW) ANSI_ESC_END},
      {"fg.bright.blue}",   ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_BLUE) ANSI_ESC_END},
      {"fg.bright.purple}", ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_PURPLE) ANSI_ESC_END},
      {"fg.bright.cyan}",   ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_CYAN) ANSI_ESC_END},
      {"fg.bright.white}",  ANSI_ESC_START _TO_STR(ANSI_FG_COLOR_BRIGHT_WHITE) ANSI_ESC_END},
      {"bg.black}",         ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BLACK) ANSI_ESC_END},
      {"bg.red}",           ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_RED) ANSI_ESC_END},
      {"bg.green}",         ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_GREEN) ANSI_ESC_END},
      {"bg.yellow}",        ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_YELLOW) ANSI_ESC_END},
      {"bg.blue}",          ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BLUE) ANSI_ESC_END},
      {"bg.purple}",        ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_PURPLE) ANSI_ESC_END},
      {"bg.cyan}",          ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_CYAN) ANSI_ESC_END},
      {"bg.white}",         ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_WHITE) ANSI_ESC_END},
      {"bg.bright.black}",  ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_BLACK) ANSI_ESC_END},
      {"bg.bright.red}",    ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_RED) ANSI_ESC_END},
      {"bg.bright.green}",  ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_GREEN) ANSI_ESC_END},
      {"bg.bright.yellow}", ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_YELLOW) ANSI_ESC_END},
      {"bg.bright.blue}",   ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_BLUE) ANSI_ESC_END},
      {"bg.bright.purple}", ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_PURPLE) ANSI_ESC_END},
      {"bg.bright.cyan}",   ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_CYAN) ANSI_ESC_END},
      {"bg.bright.white}",  ANSI_ESC_START _TO_STR(ANSI_BG_COLOR_BRIGHT_WHITE) ANSI_ESC_END},
      {"normal}",           ANSI_ESC_START _TO_STR(ANSI_CTRL_NORMAL) ANSI_ESC_END},
      {"bold}",             ANSI_ESC_START _TO_STR(ANSI_CTRL_BOLD) ANSI_ESC_END},
      {"faint}",            ANSI_ESC_START _TO_STR(ANSI_CTRL_FAINT) ANSI_ESC_END},
      {"italic}",           ANSI_ESC_START _TO_STR(ANSI_CTRL_ITALIC) ANSI_ESC_END},
      {"underline}",        ANSI_ESC_START _TO_STR(ANSI_CTRL_UNDERLINE) ANSI_ESC_END},
      {"slow-blink}",       ANSI_ESC_START _TO_STR(ANSI_CTRL_SLOW_BLINK) ANSI_ESC_END},
      {"fast-blink}",       ANSI_ESC_START _TO_STR(ANSI_CTRL_FAST_BLINK) ANSI_ESC_END},
      {"negative}",         ANSI_ESC_START _TO_STR(ANSI_CTRL_IMAGE_NEGATIVE) ANSI_ESC_END},
      {"conceal}",          ANSI_ESC_START _TO_STR(ANSI_CTRL_CONCEAL) ANSI_ESC_END},
      {"crossed-out}",      ANSI_ESC_START _TO_STR(ANSI_CTRL_CROSSED_OUT) ANSI_ESC_END},
#undef _TO_STR
#undef _TO_STR2
  };
  // clang-format on
  auto codes = llvm::ArrayRef(g_color_tokens);
 
  static const char tok_hdr[] = "${ansi.";
 
  std::string fmt;
  while (!format.empty()) {
    llvm::StringRef left, right;
    std::tie(left, right) = format.split(tok_hdr);
 
    fmt += left;
 
    if (left == format && right.empty()) {
      // The header was not found.  Just exit.
      break;
    }
 
    bool found_code = false;
    for (const auto &code : codes) {
      if (!right.consume_front(code.name))
        continue;
 
      if (do_color)
        fmt.append(code.value);
      found_code = true;
      break;
    }
    format = right;
    // If we haven't found a valid replacement value, we just copy the string
    // to the result without any modifications.
    if (!found_code)
      fmt.append(tok_hdr);
  }
  return fmt;
}
 
inline std::tuple<llvm::StringRef, llvm::StringRef, llvm::StringRef>
FindNextAnsiSequence(llvm::StringRef str) {
  llvm::StringRef left;
  llvm::StringRef right = str;
 
  while (!right.empty()) {
    const size_t start = right.find(ANSI_ESC_START);
 
    // ANSI_ESC_START not found.
    if (start == llvm::StringRef::npos)
      return {str, {}, {}};
 
    // Split the string around the current ANSI_ESC_START.
    left = str.take_front(left.size() + start);
    llvm::StringRef escape = right.substr(start);
    right = right.substr(start + ANSI_ESC_START_LEN + 1);
 
    const size_t end = right.find_first_not_of("0123456789;");
 
    // ANSI_ESC_END found.
    if (end < right.size() && (right[end] == 'm' || right[end] == 'G'))
      return {left, escape.take_front(ANSI_ESC_START_LEN + 1 + end + 1),
              right.substr(end + 1)};
 
    // Maintain the invariant that str == left + right at the start of the loop.
    left = str.take_front(left.size() + ANSI_ESC_START_LEN + 1);
  }
 
  return {str, {}, {}};
}
 
inline std::string StripAnsiTerminalCodes(llvm::StringRef str) {
  std::string stripped;
  while (!str.empty()) {
    auto [left, escape, right] = FindNextAnsiSequence(str);
    stripped += left;
    str = right;
  }
  return stripped;
}
 
inline std::string TrimAndPad(llvm::StringRef str, size_t visible_length,
                              char padding = ' ') {
  std::string result;
  result.reserve(visible_length);
  size_t result_visibile_length = 0;
 
  // Trim the string to the given visible length.
  while (!str.empty()) {
    auto [left, escape, right] = FindNextAnsiSequence(str);
    str = right;
 
    // Compute the length of the string without escape codes. If it fits, append
    // it together with the invisible escape code.
    size_t column_width = llvm::sys::locale::columnWidth(left);
    if (result_visibile_length + column_width <= visible_length) {
      result.append(left).append(escape);
      result_visibile_length += column_width;
      continue;
    }
 
    // The string might contain unicode which means it's not safe to truncate.
    // Repeatedly trim the string until it its valid unicode and fits.
    llvm::StringRef trimmed = left;
    while (!trimmed.empty()) {
      // This relies on columnWidth returning -2 for invalid/partial unicode
      // characters, which after conversion to size_t will be larger than the
      // visible width.
      column_width = llvm::sys::locale::columnWidth(trimmed);
      if (result_visibile_length + column_width <= visible_length) {
        result.append(trimmed);
        result_visibile_length += column_width;
        break;
      }
      trimmed = trimmed.drop_back();
    }
  }
 
  // Pad the string.
  if (result_visibile_length < visible_length)
    result.append(visible_length - result_visibile_length, padding);
 
  return result;
}
 
inline size_t ColumnWidth(llvm::StringRef str) {
  std::string stripped = ansi::StripAnsiTerminalCodes(str);
  return llvm::sys::locale::columnWidth(stripped);
}
 
} // namespace ansi
} // namespace lldb_private
 
#endif