docs: explain how to deal with files that are always modified
[git.git] / color.c
blob64f52a4f93a21c4abe5e40e8957ec6115ca46c2a
1 #include "cache.h"
2 #include "config.h"
3 #include "color.h"
5 static int git_use_color_default = GIT_COLOR_AUTO;
6 int color_stdout_is_tty = -1;
8 /*
9 * The list of available column colors.
11 const char *column_colors_ansi[] = {
12 GIT_COLOR_RED,
13 GIT_COLOR_GREEN,
14 GIT_COLOR_YELLOW,
15 GIT_COLOR_BLUE,
16 GIT_COLOR_MAGENTA,
17 GIT_COLOR_CYAN,
18 GIT_COLOR_BOLD_RED,
19 GIT_COLOR_BOLD_GREEN,
20 GIT_COLOR_BOLD_YELLOW,
21 GIT_COLOR_BOLD_BLUE,
22 GIT_COLOR_BOLD_MAGENTA,
23 GIT_COLOR_BOLD_CYAN,
24 GIT_COLOR_RESET,
27 enum {
28 COLOR_BACKGROUND_OFFSET = 10,
29 COLOR_FOREGROUND_ANSI = 30,
30 COLOR_FOREGROUND_RGB = 38,
31 COLOR_FOREGROUND_256 = 38,
32 COLOR_FOREGROUND_BRIGHT_ANSI = 90,
35 /* Ignore the RESET at the end when giving the size */
36 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
38 /* An individual foreground or background color. */
39 struct color {
40 enum {
41 COLOR_UNSPECIFIED = 0,
42 COLOR_NORMAL,
43 COLOR_ANSI, /* basic 0-7 ANSI colors */
44 COLOR_256,
45 COLOR_RGB
46 } type;
47 /* The numeric value for ANSI and 256-color modes */
48 unsigned char value;
49 /* 24-bit RGB color values */
50 unsigned char red, green, blue;
54 * "word" is a buffer of length "len"; does it match the NUL-terminated
55 * "match" exactly?
57 static int match_word(const char *word, int len, const char *match)
59 return !strncasecmp(word, match, len) && !match[len];
62 static int get_hex_color(const char *in, unsigned char *out)
64 unsigned int val;
65 val = (hexval(in[0]) << 4) | hexval(in[1]);
66 if (val & ~0xff)
67 return -1;
68 *out = val;
69 return 0;
73 * If an ANSI color is recognized in "name", fill "out" and return 0.
74 * Otherwise, leave out unchanged and return -1.
76 static int parse_ansi_color(struct color *out, const char *name, int len)
78 /* Positions in array must match ANSI color codes */
79 static const char * const color_names[] = {
80 "black", "red", "green", "yellow",
81 "blue", "magenta", "cyan", "white"
83 int i;
84 int color_offset = COLOR_FOREGROUND_ANSI;
86 if (strncasecmp(name, "bright", 6) == 0) {
87 color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
88 name += 6;
89 len -= 6;
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 + color_offset;
95 return 0;
98 return -1;
101 static int parse_color(struct color *out, const char *name, int len)
103 char *end;
104 long val;
106 /* First try the special word "normal"... */
107 if (match_word(name, len, "normal")) {
108 out->type = COLOR_NORMAL;
109 return 0;
112 /* Try a 24-bit RGB value */
113 if (len == 7 && name[0] == '#') {
114 if (!get_hex_color(name + 1, &out->red) &&
115 !get_hex_color(name + 3, &out->green) &&
116 !get_hex_color(name + 5, &out->blue)) {
117 out->type = COLOR_RGB;
118 return 0;
122 /* Then pick from our human-readable color names... */
123 if (parse_ansi_color(out, name, len) == 0) {
124 return 0;
127 /* And finally try a literal 256-color-mode number */
128 val = strtol(name, &end, 10);
129 if (end - name == len) {
131 * Allow "-1" as an alias for "normal", but other negative
132 * numbers are bogus.
134 if (val < -1)
135 ; /* fall through to error */
136 else if (val < 0) {
137 out->type = COLOR_NORMAL;
138 return 0;
139 /* Rewrite 0-7 as more-portable standard colors. */
140 } else if (val < 8) {
141 out->type = COLOR_ANSI;
142 out->value = val + COLOR_FOREGROUND_ANSI;
143 return 0;
144 /* Rewrite 8-15 as more-portable aixterm colors. */
145 } else if (val < 16) {
146 out->type = COLOR_ANSI;
147 out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
148 return 0;
149 } else if (val < 256) {
150 out->type = COLOR_256;
151 out->value = val;
152 return 0;
156 return -1;
159 static int parse_attr(const char *name, size_t len)
161 static const struct {
162 const char *name;
163 size_t len;
164 int val, neg;
165 } attrs[] = {
166 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
167 ATTR("bold", 1, 22),
168 ATTR("dim", 2, 22),
169 ATTR("italic", 3, 23),
170 ATTR("ul", 4, 24),
171 ATTR("blink", 5, 25),
172 ATTR("reverse", 7, 27),
173 ATTR("strike", 9, 29)
174 #undef ATTR
176 int negate = 0;
177 int i;
179 if (skip_prefix_mem(name, len, "no", &name, &len)) {
180 skip_prefix_mem(name, len, "-", &name, &len);
181 negate = 1;
184 for (i = 0; i < ARRAY_SIZE(attrs); i++) {
185 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
186 return negate ? attrs[i].neg : attrs[i].val;
188 return -1;
191 int color_parse(const char *value, char *dst)
193 return color_parse_mem(value, strlen(value), dst);
197 * Write the ANSI color codes for "c" to "out"; the string should
198 * already have the ANSI escape code in it. "out" should have enough
199 * space in it to fit any color.
201 static char *color_output(char *out, int len, const struct color *c, int background)
203 int offset = 0;
205 if (background)
206 offset = COLOR_BACKGROUND_OFFSET;
207 switch (c->type) {
208 case COLOR_UNSPECIFIED:
209 case COLOR_NORMAL:
210 break;
211 case COLOR_ANSI:
212 out += xsnprintf(out, len, "%d", c->value + offset);
213 break;
214 case COLOR_256:
215 out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
216 c->value);
217 break;
218 case COLOR_RGB:
219 out += xsnprintf(out, len, "%d;2;%d;%d;%d",
220 COLOR_FOREGROUND_RGB + offset,
221 c->red, c->green, c->blue);
222 break;
224 return out;
227 static int color_empty(const struct color *c)
229 return c->type <= COLOR_NORMAL;
232 int color_parse_mem(const char *value, int value_len, char *dst)
234 const char *ptr = value;
235 int len = value_len;
236 char *end = dst + COLOR_MAXLEN;
237 unsigned int attr = 0;
238 struct color fg = { COLOR_UNSPECIFIED };
239 struct color bg = { COLOR_UNSPECIFIED };
241 while (len > 0 && isspace(*ptr)) {
242 ptr++;
243 len--;
246 if (!len) {
247 dst[0] = '\0';
248 return 0;
251 if (!strncasecmp(ptr, "reset", len)) {
252 xsnprintf(dst, end - dst, GIT_COLOR_RESET);
253 return 0;
256 /* [fg [bg]] [attr]... */
257 while (len > 0) {
258 const char *word = ptr;
259 struct color c = { COLOR_UNSPECIFIED };
260 int val, wordlen = 0;
262 while (len > 0 && !isspace(word[wordlen])) {
263 wordlen++;
264 len--;
267 ptr = word + wordlen;
268 while (len > 0 && isspace(*ptr)) {
269 ptr++;
270 len--;
273 if (!parse_color(&c, word, wordlen)) {
274 if (fg.type == COLOR_UNSPECIFIED) {
275 fg = c;
276 continue;
278 if (bg.type == COLOR_UNSPECIFIED) {
279 bg = c;
280 continue;
282 goto bad;
284 val = parse_attr(word, wordlen);
285 if (0 <= val)
286 attr |= (1 << val);
287 else
288 goto bad;
291 #undef OUT
292 #define OUT(x) do { \
293 if (dst == end) \
294 BUG("color parsing ran out of space"); \
295 *dst++ = (x); \
296 } while(0)
298 if (attr || !color_empty(&fg) || !color_empty(&bg)) {
299 int sep = 0;
300 int i;
302 OUT('\033');
303 OUT('[');
305 for (i = 0; attr; i++) {
306 unsigned bit = (1 << i);
307 if (!(attr & bit))
308 continue;
309 attr &= ~bit;
310 if (sep++)
311 OUT(';');
312 dst += xsnprintf(dst, end - dst, "%d", i);
314 if (!color_empty(&fg)) {
315 if (sep++)
316 OUT(';');
317 dst = color_output(dst, end - dst, &fg, 0);
319 if (!color_empty(&bg)) {
320 if (sep++)
321 OUT(';');
322 dst = color_output(dst, end - dst, &bg, 1);
324 OUT('m');
326 OUT(0);
327 return 0;
328 bad:
329 return error(_("invalid color value: %.*s"), value_len, value);
330 #undef OUT
333 int git_config_colorbool(const char *var, const char *value)
335 if (value) {
336 if (!strcasecmp(value, "never"))
337 return 0;
338 if (!strcasecmp(value, "always"))
339 return 1;
340 if (!strcasecmp(value, "auto"))
341 return GIT_COLOR_AUTO;
344 if (!var)
345 return -1;
347 /* Missing or explicit false to turn off colorization */
348 if (!git_config_bool(var, value))
349 return 0;
351 /* any normal truth value defaults to 'auto' */
352 return GIT_COLOR_AUTO;
355 static int check_auto_color(int fd)
357 static int color_stderr_is_tty = -1;
358 int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
359 if (*is_tty_p < 0)
360 *is_tty_p = isatty(fd);
361 if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
362 if (!is_terminal_dumb())
363 return 1;
365 return 0;
368 int want_color_fd(int fd, int var)
371 * NEEDSWORK: This function is sometimes used from multiple threads, and
372 * we end up using want_auto racily. That "should not matter" since
373 * we always write the same value, but it's still wrong. This function
374 * is listed in .tsan-suppressions for the time being.
377 static int want_auto[3] = { -1, -1, -1 };
379 if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
380 BUG("file descriptor out of range: %d", fd);
382 if (var < 0)
383 var = git_use_color_default;
385 if (var == GIT_COLOR_AUTO) {
386 if (want_auto[fd] < 0)
387 want_auto[fd] = check_auto_color(fd);
388 return want_auto[fd];
390 return var;
393 int git_color_config(const char *var, const char *value, void *cb)
395 if (!strcmp(var, "color.ui")) {
396 git_use_color_default = git_config_colorbool(var, value);
397 return 0;
400 return 0;
403 int git_color_default_config(const char *var, const char *value, void *cb)
405 if (git_color_config(var, value, cb) < 0)
406 return -1;
408 return git_default_config(var, value, cb);
411 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
413 if (*color)
414 fprintf(fp, "%s", color);
415 fprintf(fp, "%s", sb->buf);
416 if (*color)
417 fprintf(fp, "%s", GIT_COLOR_RESET);
420 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
421 va_list args, const char *trail)
423 int r = 0;
425 if (*color)
426 r += fprintf(fp, "%s", color);
427 r += vfprintf(fp, fmt, args);
428 if (*color)
429 r += fprintf(fp, "%s", GIT_COLOR_RESET);
430 if (trail)
431 r += fprintf(fp, "%s", trail);
432 return r;
435 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
437 va_list args;
438 int r;
439 va_start(args, fmt);
440 r = color_vfprintf(fp, color, fmt, args, NULL);
441 va_end(args);
442 return r;
445 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
447 va_list args;
448 int r;
449 va_start(args, fmt);
450 r = color_vfprintf(fp, color, fmt, args, "\n");
451 va_end(args);
452 return r;
455 int color_is_nil(const char *c)
457 return !strcmp(c, "NIL");