gitattributes: Document the unified "auto" handling
[git/debian.git] / color.c
blob81c26767239f9e028057c1843f57b77640db6c26
1 #include "cache.h"
2 #include "color.h"
4 static int git_use_color_default = GIT_COLOR_AUTO;
5 int color_stdout_is_tty = -1;
7 /*
8 * The list of available column colors.
9 */
10 const char *column_colors_ansi[] = {
11 GIT_COLOR_RED,
12 GIT_COLOR_GREEN,
13 GIT_COLOR_YELLOW,
14 GIT_COLOR_BLUE,
15 GIT_COLOR_MAGENTA,
16 GIT_COLOR_CYAN,
17 GIT_COLOR_BOLD_RED,
18 GIT_COLOR_BOLD_GREEN,
19 GIT_COLOR_BOLD_YELLOW,
20 GIT_COLOR_BOLD_BLUE,
21 GIT_COLOR_BOLD_MAGENTA,
22 GIT_COLOR_BOLD_CYAN,
23 GIT_COLOR_RESET,
26 /* Ignore the RESET at the end when giving the size */
27 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
29 /* An individual foreground or background color. */
30 struct color {
31 enum {
32 COLOR_UNSPECIFIED = 0,
33 COLOR_NORMAL,
34 COLOR_ANSI, /* basic 0-7 ANSI colors */
35 COLOR_256,
36 COLOR_RGB
37 } type;
38 /* The numeric value for ANSI and 256-color modes */
39 unsigned char value;
40 /* 24-bit RGB color values */
41 unsigned char red, green, blue;
45 * "word" is a buffer of length "len"; does it match the NUL-terminated
46 * "match" exactly?
48 static int match_word(const char *word, int len, const char *match)
50 return !strncasecmp(word, match, len) && !match[len];
53 static int get_hex_color(const char *in, unsigned char *out)
55 unsigned int val;
56 val = (hexval(in[0]) << 4) | hexval(in[1]);
57 if (val & ~0xff)
58 return -1;
59 *out = val;
60 return 0;
63 static int parse_color(struct color *out, const char *name, int len)
65 /* Positions in array must match ANSI color codes */
66 static const char * const color_names[] = {
67 "black", "red", "green", "yellow",
68 "blue", "magenta", "cyan", "white"
70 char *end;
71 int i;
72 long val;
74 /* First try the special word "normal"... */
75 if (match_word(name, len, "normal")) {
76 out->type = COLOR_NORMAL;
77 return 0;
80 /* Try a 24-bit RGB value */
81 if (len == 7 && name[0] == '#') {
82 if (!get_hex_color(name + 1, &out->red) &&
83 !get_hex_color(name + 3, &out->green) &&
84 !get_hex_color(name + 5, &out->blue)) {
85 out->type = COLOR_RGB;
86 return 0;
90 /* Then pick from our human-readable color names... */
91 for (i = 0; i < ARRAY_SIZE(color_names); i++) {
92 if (match_word(name, len, color_names[i])) {
93 out->type = COLOR_ANSI;
94 out->value = i;
95 return 0;
99 /* And finally try a literal 256-color-mode number */
100 val = strtol(name, &end, 10);
101 if (end - name == len) {
103 * Allow "-1" as an alias for "normal", but other negative
104 * numbers are bogus.
106 if (val < -1)
107 ; /* fall through to error */
108 else if (val < 0) {
109 out->type = COLOR_NORMAL;
110 return 0;
111 /* Rewrite low numbers as more-portable standard colors. */
112 } else if (val < 8) {
113 out->type = COLOR_ANSI;
114 out->value = val;
115 return 0;
116 } else if (val < 256) {
117 out->type = COLOR_256;
118 out->value = val;
119 return 0;
123 return -1;
126 static int parse_attr(const char *name, size_t len)
128 static const struct {
129 const char *name;
130 size_t len;
131 int val, neg;
132 } attrs[] = {
133 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
134 ATTR("bold", 1, 22),
135 ATTR("dim", 2, 22),
136 ATTR("italic", 3, 23),
137 ATTR("ul", 4, 24),
138 ATTR("blink", 5, 25),
139 ATTR("reverse", 7, 27),
140 ATTR("strike", 9, 29)
141 #undef ATTR
143 int negate = 0;
144 int i;
146 if (skip_prefix_mem(name, len, "no", &name, &len)) {
147 skip_prefix_mem(name, len, "-", &name, &len);
148 negate = 1;
151 for (i = 0; i < ARRAY_SIZE(attrs); i++) {
152 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
153 return negate ? attrs[i].neg : attrs[i].val;
155 return -1;
158 int color_parse(const char *value, char *dst)
160 return color_parse_mem(value, strlen(value), dst);
163 void color_set(char *dst, const char *color_bytes)
165 xsnprintf(dst, COLOR_MAXLEN, "%s", color_bytes);
169 * Write the ANSI color codes for "c" to "out"; the string should
170 * already have the ANSI escape code in it. "out" should have enough
171 * space in it to fit any color.
173 static char *color_output(char *out, int len, const struct color *c, char type)
175 switch (c->type) {
176 case COLOR_UNSPECIFIED:
177 case COLOR_NORMAL:
178 break;
179 case COLOR_ANSI:
180 if (len < 2)
181 die("BUG: color parsing ran out of space");
182 *out++ = type;
183 *out++ = '0' + c->value;
184 break;
185 case COLOR_256:
186 out += xsnprintf(out, len, "%c8;5;%d", type, c->value);
187 break;
188 case COLOR_RGB:
189 out += xsnprintf(out, len, "%c8;2;%d;%d;%d", type,
190 c->red, c->green, c->blue);
191 break;
193 return out;
196 static int color_empty(const struct color *c)
198 return c->type <= COLOR_NORMAL;
201 int color_parse_mem(const char *value, int value_len, char *dst)
203 const char *ptr = value;
204 int len = value_len;
205 char *end = dst + COLOR_MAXLEN;
206 unsigned int attr = 0;
207 struct color fg = { COLOR_UNSPECIFIED };
208 struct color bg = { COLOR_UNSPECIFIED };
210 if (!strncasecmp(value, "reset", len)) {
211 xsnprintf(dst, end - dst, GIT_COLOR_RESET);
212 return 0;
215 /* [fg [bg]] [attr]... */
216 while (len > 0) {
217 const char *word = ptr;
218 struct color c;
219 int val, wordlen = 0;
221 while (len > 0 && !isspace(word[wordlen])) {
222 wordlen++;
223 len--;
226 ptr = word + wordlen;
227 while (len > 0 && isspace(*ptr)) {
228 ptr++;
229 len--;
232 if (!parse_color(&c, word, wordlen)) {
233 if (fg.type == COLOR_UNSPECIFIED) {
234 fg = c;
235 continue;
237 if (bg.type == COLOR_UNSPECIFIED) {
238 bg = c;
239 continue;
241 goto bad;
243 val = parse_attr(word, wordlen);
244 if (0 <= val)
245 attr |= (1 << val);
246 else
247 goto bad;
250 #undef OUT
251 #define OUT(x) do { \
252 if (dst == end) \
253 die("BUG: color parsing ran out of space"); \
254 *dst++ = (x); \
255 } while(0)
257 if (attr || !color_empty(&fg) || !color_empty(&bg)) {
258 int sep = 0;
259 int i;
261 OUT('\033');
262 OUT('[');
264 for (i = 0; attr; i++) {
265 unsigned bit = (1 << i);
266 if (!(attr & bit))
267 continue;
268 attr &= ~bit;
269 if (sep++)
270 OUT(';');
271 dst += xsnprintf(dst, end - dst, "%d", i);
273 if (!color_empty(&fg)) {
274 if (sep++)
275 OUT(';');
276 /* foreground colors are all in the 3x range */
277 dst = color_output(dst, end - dst, &fg, '3');
279 if (!color_empty(&bg)) {
280 if (sep++)
281 OUT(';');
282 /* background colors are all in the 4x range */
283 dst = color_output(dst, end - dst, &bg, '4');
285 OUT('m');
287 OUT(0);
288 return 0;
289 bad:
290 return error(_("invalid color value: %.*s"), value_len, value);
291 #undef OUT
294 int git_config_colorbool(const char *var, const char *value)
296 if (value) {
297 if (!strcasecmp(value, "never"))
298 return 0;
299 if (!strcasecmp(value, "always"))
300 return 1;
301 if (!strcasecmp(value, "auto"))
302 return GIT_COLOR_AUTO;
305 if (!var)
306 return -1;
308 /* Missing or explicit false to turn off colorization */
309 if (!git_config_bool(var, value))
310 return 0;
312 /* any normal truth value defaults to 'auto' */
313 return GIT_COLOR_AUTO;
316 static int check_auto_color(void)
318 if (color_stdout_is_tty < 0)
319 color_stdout_is_tty = isatty(1);
320 if (color_stdout_is_tty || (pager_in_use() && pager_use_color)) {
321 char *term = getenv("TERM");
322 if (term && strcmp(term, "dumb"))
323 return 1;
325 return 0;
328 int want_color(int var)
330 static int want_auto = -1;
332 if (var < 0)
333 var = git_use_color_default;
335 if (var == GIT_COLOR_AUTO) {
336 if (want_auto < 0)
337 want_auto = check_auto_color();
338 return want_auto;
340 return var;
343 int git_color_config(const char *var, const char *value, void *cb)
345 if (!strcmp(var, "color.ui")) {
346 git_use_color_default = git_config_colorbool(var, value);
347 return 0;
350 return 0;
353 int git_color_default_config(const char *var, const char *value, void *cb)
355 if (git_color_config(var, value, cb) < 0)
356 return -1;
358 return git_default_config(var, value, cb);
361 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
363 if (*color)
364 fprintf(fp, "%s", color);
365 fprintf(fp, "%s", sb->buf);
366 if (*color)
367 fprintf(fp, "%s", GIT_COLOR_RESET);
370 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
371 va_list args, const char *trail)
373 int r = 0;
375 if (*color)
376 r += fprintf(fp, "%s", color);
377 r += vfprintf(fp, fmt, args);
378 if (*color)
379 r += fprintf(fp, "%s", GIT_COLOR_RESET);
380 if (trail)
381 r += fprintf(fp, "%s", trail);
382 return r;
387 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
389 va_list args;
390 int r;
391 va_start(args, fmt);
392 r = color_vfprintf(fp, color, fmt, args, NULL);
393 va_end(args);
394 return r;
397 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
399 va_list args;
400 int r;
401 va_start(args, fmt);
402 r = color_vfprintf(fp, color, fmt, args, "\n");
403 va_end(args);
404 return r;
407 int color_is_nil(const char *c)
409 return !strcmp(c, "NIL");