1 /* Terminal color manipulation macros. 2 Copyright (C) 2005-2020 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_COLOR_MACROS_H 21 #define GCC_COLOR_MACROS_H 22 23 /* Select Graphic Rendition (SGR, "\33[...m") strings. */ 24 /* Also Erase in Line (EL) to Right ("\33[K") by default. */ 25 /* Why have EL to Right after SGR? 26 -- The behavior of line-wrapping when at the bottom of the 27 terminal screen and at the end of the current line is often 28 such that a new line is introduced, entirely cleared with 29 the current background color which may be different from the 30 default one (see the boolean back_color_erase terminfo(5) 31 capability), thus scrolling the display by one line. 32 The end of this new line will stay in this background color 33 even after reverting to the default background color with 34 "\33[m', unless it is explicitly cleared again with "\33[K" 35 (which is the behavior the user would instinctively expect 36 from the whole thing). There may be some unavoidable 37 background-color flicker at the end of this new line because 38 of this (when timing with the monitor's redraw is just right). 39 -- The behavior of HT (tab, "\t") is usually the same as that of 40 Cursor Forward Tabulation (CHT) with a default parameter 41 of 1 ("\33[I"), i.e., it performs pure movement to the next 42 tab stop, without any clearing of either content or screen 43 attributes (including background color); try 44 printf 'asdfqwerzxcv\rASDF\tZXCV\n' 45 in a bash(1) shell to demonstrate this. This is not what the 46 user would instinctively expect of HT (but is ok for CHT). 47 The instinctive behavior would include clearing the terminal 48 cells that are skipped over by HT with blank cells in the 49 current screen attributes, including background color; 50 the boolean dest_tabs_magic_smso terminfo(5) capability 51 indicates this saner behavior for HT, but only some rare 52 terminals have it (although it also indicates a special 53 glitch with standout mode in the Teleray terminal for which 54 it was initially introduced). The remedy is to add "\33K" 55 after each SGR sequence, be it START (to fix the behavior 56 of any HT after that before another SGR) or END (to fix the 57 behavior of an HT in default background color that would 58 follow a line-wrapping at the bottom of the screen in another 59 background color, and to complement doing it after START). 60 Piping GCC's output through a pager such as less(1) avoids 61 any HT problems since the pager performs tab expansion. 62 63 Generic disadvantages of this remedy are: 64 -- Some very rare terminals might support SGR but not EL (nobody 65 will use "gcc -fdiagnostics-color" on a terminal that does not 66 support SGR in the first place). 67 -- Having these extra control sequences might somewhat complicate 68 the task of any program trying to parse "gcc -fdiagnostics-color" 69 output in order to extract structuring information from it. 70 A specific disadvantage to doing it after SGR START is: 71 -- Even more possible background color flicker (when timing 72 with the monitor's redraw is just right), even when not at the 73 bottom of the screen. 74 There are no additional disadvantages specific to doing it after 75 SGR END. 76 77 It would be impractical for GCC to become a full-fledged 78 terminal program linked against ncurses or the like, so it will 79 not detect terminfo(5) capabilities. */ 80 81 #define COLOR_SEPARATOR ";" 82 #define COLOR_NONE "00" 83 #define COLOR_BOLD "01" 84 #define COLOR_UNDERSCORE "04" 85 #define COLOR_BLINK "05" 86 #define COLOR_REVERSE "07" 87 #define COLOR_FG_BLACK "30" 88 #define COLOR_FG_RED "31" 89 #define COLOR_FG_GREEN "32" 90 #define COLOR_FG_YELLOW "33" 91 #define COLOR_FG_BLUE "34" 92 #define COLOR_FG_MAGENTA "35" 93 #define COLOR_FG_CYAN "36" 94 #define COLOR_FG_WHITE "37" 95 #define COLOR_BG_BLACK "40" 96 #define COLOR_BG_RED "41" 97 #define COLOR_BG_GREEN "42" 98 #define COLOR_BG_YELLOW "43" 99 #define COLOR_BG_BLUE "44" 100 #define COLOR_BG_MAGENTA "45" 101 #define COLOR_BG_CYAN "46" 102 #define COLOR_BG_WHITE "47" 103 #define SGR_START "\33[" 104 #define SGR_END "m\33[K" 105 #define SGR_SEQ(str) SGR_START str SGR_END 106 #define SGR_RESET SGR_SEQ("") 107 108 #endif /* GCC_COLOR_MACROS_H */ 109