color: introduce support for colorizing stderr
[git/git.git] / color.h
1 #ifndef COLOR_H
2 #define COLOR_H
3
4 struct strbuf;
5
6 /*
7 * The maximum length of ANSI color sequence we would generate:
8 * - leading ESC '[' 2
9 * - attr + ';' 2 * num_attr (e.g. "1;")
10 * - no-attr + ';' 3 * num_attr (e.g. "22;")
11 * - fg color + ';' 17 (e.g. "38;2;255;255;255;")
12 * - bg color + ';' 17 (e.g. "48;2;255;255;255;")
13 * - terminating 'm' NUL 2
14 *
15 * The above overcounts by one semicolon but it is close enough.
16 *
17 * The space for attributes is also slightly overallocated, as
18 * the negation for some attributes is the same (e.g., nobold and nodim).
19 *
20 * We allocate space for 7 attributes.
21 */
22 #define COLOR_MAXLEN 75
23
24 #define GIT_COLOR_NORMAL ""
25 #define GIT_COLOR_RESET "\033[m"
26 #define GIT_COLOR_BOLD "\033[1m"
27 #define GIT_COLOR_RED "\033[31m"
28 #define GIT_COLOR_GREEN "\033[32m"
29 #define GIT_COLOR_YELLOW "\033[33m"
30 #define GIT_COLOR_BLUE "\033[34m"
31 #define GIT_COLOR_MAGENTA "\033[35m"
32 #define GIT_COLOR_CYAN "\033[36m"
33 #define GIT_COLOR_BOLD_RED "\033[1;31m"
34 #define GIT_COLOR_BOLD_GREEN "\033[1;32m"
35 #define GIT_COLOR_BOLD_YELLOW "\033[1;33m"
36 #define GIT_COLOR_BOLD_BLUE "\033[1;34m"
37 #define GIT_COLOR_BOLD_MAGENTA "\033[1;35m"
38 #define GIT_COLOR_BOLD_CYAN "\033[1;36m"
39 #define GIT_COLOR_BG_RED "\033[41m"
40 #define GIT_COLOR_BG_GREEN "\033[42m"
41 #define GIT_COLOR_BG_YELLOW "\033[43m"
42 #define GIT_COLOR_BG_BLUE "\033[44m"
43 #define GIT_COLOR_BG_MAGENTA "\033[45m"
44 #define GIT_COLOR_BG_CYAN "\033[46m"
45 #define GIT_COLOR_FAINT "\033[2m"
46 #define GIT_COLOR_FAINT_ITALIC "\033[2;3m"
47
48 /* A special value meaning "no color selected" */
49 #define GIT_COLOR_NIL "NIL"
50
51 /*
52 * The first three are chosen to match common usage in the code, and what is
53 * returned from git_config_colorbool. The "auto" value can be returned from
54 * config_colorbool, and will be converted by want_color() into either 0 or 1.
55 */
56 #define GIT_COLOR_UNKNOWN -1
57 #define GIT_COLOR_NEVER 0
58 #define GIT_COLOR_ALWAYS 1
59 #define GIT_COLOR_AUTO 2
60
61 /* A default list of colors to use for commit graphs and show-branch output */
62 extern const char *column_colors_ansi[];
63 extern const int column_colors_ansi_max;
64
65 /*
66 * Generally the color code will lazily figure this out itself, but
67 * this provides a mechanism for callers to override autodetection.
68 */
69 extern int color_stdout_is_tty;
70
71 /*
72 * Use the first one if you need only color config; the second is a convenience
73 * if you are just going to change to git_default_config, too.
74 */
75 int git_color_config(const char *var, const char *value, void *cb);
76 int git_color_default_config(const char *var, const char *value, void *cb);
77
78 /*
79 * Parse a config option, which can be a boolean or one of
80 * "never", "auto", "always". Return a constant of
81 * GIT_COLOR_NEVER for "never" or negative boolean,
82 * GIT_COLOR_ALWAYS for "always" or a positive boolean,
83 * and GIT_COLOR_AUTO for "auto".
84 */
85 int git_config_colorbool(const char *var, const char *value);
86
87 /*
88 * Return a boolean whether to use color, where the argument 'var' is
89 * one of GIT_COLOR_UNKNOWN, GIT_COLOR_NEVER, GIT_COLOR_ALWAYS, GIT_COLOR_AUTO.
90 */
91 int want_color_fd(int fd, int var);
92 #define want_color(colorbool) want_color_fd(1, (colorbool))
93 #define want_color_stderr(colorbool) want_color_fd(2, (colorbool))
94
95 /*
96 * Translate a Git color from 'value' into a string that the terminal can
97 * interpret and store it into 'dst'. The Git color values are of the form
98 * "foreground [background] [attr]" where fore- and background can be a color
99 * name ("red"), a RGB code (#0xFF0000) or a 256-color-mode from the terminal.
100 */
101 int color_parse(const char *value, char *dst);
102 int color_parse_mem(const char *value, int len, char *dst);
103
104 /*
105 * Output the formatted string in the specified color (and then reset to normal
106 * color so subsequent output is uncolored). Omits the color encapsulation if
107 * `color` is NULL. The `color_fprintf_ln` prints a new line after resetting
108 * the color. The `color_print_strbuf` prints the contents of the given
109 * strbuf (BUG: but only up to its first NUL character).
110 */
111 __attribute__((format (printf, 3, 4)))
112 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...);
113 __attribute__((format (printf, 3, 4)))
114 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...);
115 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb);
116
117 /*
118 * Check if the given color is GIT_COLOR_NIL that means "no color selected".
119 * The caller needs to replace the color with the actual desired color.
120 */
121 int color_is_nil(const char *color);
122
123 #endif /* COLOR_H */