1 /* Output colorization.
2 Copyright (C) 2011-2020 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
21 #include "diagnostic-color.h"
22 #include "diagnostic-url.h"
28 #include "color-macros.h"
30 /* The context and logic for choosing default --color screen attributes
31 (foreground and background colors, etc.) are the following.
32 -- There are eight basic colors available, each with its own
33 nominal luminosity to the human eye and foreground/background
34 codes (black [0 %, 30/40], blue [11 %, 34/44], red [30 %, 31/41],
35 magenta [41 %, 35/45], green [59 %, 32/42], cyan [70 %, 36/46],
36 yellow [89 %, 33/43], and white [100 %, 37/47]).
37 -- Sometimes, white as a background is actually implemented using
38 a shade of light gray, so that a foreground white can be visible
39 on top of it (but most often not).
40 -- Sometimes, black as a foreground is actually implemented using
41 a shade of dark gray, so that it can be visible on top of a
42 background black (but most often not).
43 -- Sometimes, more colors are available, as extensions.
44 -- Other attributes can be selected/deselected (bold [1/22],
45 underline [4/24], standout/inverse [7/27], blink [5/25], and
46 invisible/hidden [8/28]). They are sometimes implemented by
47 using colors instead of what their names imply; e.g., bold is
48 often achieved by using brighter colors. In practice, only bold
49 is really available to us, underline sometimes being mapped by
50 the terminal to some strange color choice, and standout best
51 being left for use by downstream programs such as less(1).
52 -- We cannot assume that any of the extensions or special features
53 are available for the purpose of choosing defaults for everyone.
54 -- The most prevalent default terminal backgrounds are pure black
55 and pure white, and are not necessarily the same shades of
56 those as if they were selected explicitly with SGR sequences.
57 Some terminals use dark or light pictures as default background,
58 but those are covered over by an explicit selection of background
59 color with an SGR sequence; their users will appreciate their
60 background pictures not be covered like this, if possible.
61 -- Some uses of colors attributes is to make some output items
62 more understated (e.g., context lines); this cannot be achieved
63 by changing the background color.
64 -- For these reasons, the GCC color defaults should strive not
65 to change the background color from its default, unless it's
66 for a short item that should be highlighted, not understated.
67 -- The GCC foreground color defaults (without an explicitly set
68 background) should provide enough contrast to be readable on any
69 terminal with either a black (dark) or white (light) background.
70 This only leaves red, magenta, green, and cyan (and their bold
71 counterparts) and possibly bold blue. */
72 /* Default colors. The user can overwrite them using environment
73 variable GCC_COLORS. */
78 unsigned char name_len
;
83 static struct color_cap color_dict
[] =
85 { "error", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_RED
), 5, false },
86 { "warning", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_MAGENTA
),
88 { "note", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_CYAN
), 4, false },
89 { "range1", SGR_SEQ (COLOR_FG_GREEN
), 6, false },
90 { "range2", SGR_SEQ (COLOR_FG_BLUE
), 6, false },
91 { "locus", SGR_SEQ (COLOR_BOLD
), 5, false },
92 { "quote", SGR_SEQ (COLOR_BOLD
), 5, false },
93 { "path", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_CYAN
), 4, false },
94 { "fixit-insert", SGR_SEQ (COLOR_FG_GREEN
), 12, false },
95 { "fixit-delete", SGR_SEQ (COLOR_FG_RED
), 12, false },
96 { "diff-filename", SGR_SEQ (COLOR_BOLD
), 13, false },
97 { "diff-hunk", SGR_SEQ (COLOR_FG_CYAN
), 9, false },
98 { "diff-delete", SGR_SEQ (COLOR_FG_RED
), 11, false },
99 { "diff-insert", SGR_SEQ (COLOR_FG_GREEN
), 11, false },
100 { "type-diff", SGR_SEQ (COLOR_BOLD COLOR_SEPARATOR COLOR_FG_GREEN
), 9, false },
101 { NULL
, NULL
, 0, false }
105 colorize_start (bool show_color
, const char *name
, size_t name_len
)
107 struct color_cap
const *cap
;
112 for (cap
= color_dict
; cap
->name
; cap
++)
113 if (cap
->name_len
== name_len
114 && memcmp (cap
->name
, name
, name_len
) == 0)
116 if (cap
->name
== NULL
)
123 colorize_stop (bool show_color
)
125 return show_color
? SGR_RESET
: "";
128 /* Parse GCC_COLORS. The default would look like:
129 GCC_COLORS='error=01;31:warning=01;35:note=01;36:\
130 range1=32:range2=34:locus=01:quote=01:path=01;36:\
131 fixit-insert=32:fixit-delete=31:'\
132 diff-filename=01:diff-hunk=32:diff-delete=31:diff-insert=32:\
134 No character escaping is needed or supported. */
136 parse_gcc_colors (void)
138 const char *p
, *q
, *name
, *val
;
140 size_t name_len
= 0, val_len
= 0;
142 p
= getenv ("GCC_COLORS"); /* Plural! */
150 /* From now on, be well-formed or you're gone. */
152 if (*q
== ':' || *q
== '\0')
154 struct color_cap
*cap
;
160 /* Empty name without val (empty cap)
161 won't match and will be ignored. */
162 for (cap
= color_dict
; cap
->name
; cap
++)
163 if (cap
->name_len
== name_len
164 && memcmp (cap
->name
, name
, name_len
) == 0)
166 /* If name unknown, go on for forward compatibility. */
170 free (CONST_CAST (char *, cap
->val
));
171 b
= XNEWVEC (char, val_len
+ sizeof (SGR_SEQ ("")));
172 memcpy (b
, SGR_START
, strlen (SGR_START
));
173 memcpy (b
+ strlen (SGR_START
), val
, val_len
);
174 memcpy (b
+ strlen (SGR_START
) + val_len
, SGR_END
,
176 cap
->val
= (const char *) b
;
177 cap
->free_val
= true;
186 if (q
== name
|| val
)
190 val
= ++q
; /* Can be the empty string. */
192 else if (val
== NULL
)
193 q
++; /* Accumulate name. */
194 else if (*q
== ';' || (*q
>= '0' && *q
<= '9'))
195 q
++; /* Accumulate val. Protect the terminal from being sent
201 /* Return true if we should use color when in auto mode, false otherwise. */
203 should_colorize (void)
206 /* For consistency reasons, one should check the handle returned by
207 _get_osfhandle(_fileno(stderr)) because the function
208 pp_write_text_to_stream() in pretty-print.c calls fputs() on
209 that stream. However, the code below for non-Windows doesn't seem
210 to care about it either... */
214 h
= GetStdHandle (STD_ERROR_HANDLE
);
215 return (h
!= INVALID_HANDLE_VALUE
) && (h
!= NULL
)
216 && GetConsoleMode (h
, &m
);
218 char const *t
= getenv ("TERM");
219 return t
&& strcmp (t
, "dumb") != 0 && isatty (STDERR_FILENO
);
224 colorize_init (diagnostic_color_rule_t rule
)
228 case DIAGNOSTICS_COLOR_NO
:
230 case DIAGNOSTICS_COLOR_YES
:
231 return parse_gcc_colors ();
232 case DIAGNOSTICS_COLOR_AUTO
:
233 if (should_colorize ())
234 return parse_gcc_colors ();
242 /* Determine if URLs should be enabled, based on RULE.
243 This reuses the logic for colorization. */
246 diagnostic_urls_enabled_p (diagnostic_url_rule_t rule
)
250 case DIAGNOSTICS_URL_NO
:
252 case DIAGNOSTICS_URL_YES
:
254 case DIAGNOSTICS_URL_AUTO
:
255 return should_colorize ();