color.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "color.h"
   4 #include "hex.h"
   5
   6 static int git_use_color_default = GIT_COLOR_AUTO;
   7 int color_stdout_is_tty = -1;
   8
   9 /*
  10  * The list of available column colors.
  11  */
  12 const char *column_colors_ansi[] = {
  13         GIT_COLOR_RED,
  14         GIT_COLOR_GREEN,
  15         GIT_COLOR_YELLOW,
  16         GIT_COLOR_BLUE,
  17         GIT_COLOR_MAGENTA,
  18         GIT_COLOR_CYAN,
  19         GIT_COLOR_BOLD_RED,
  20         GIT_COLOR_BOLD_GREEN,
  21         GIT_COLOR_BOLD_YELLOW,
  22         GIT_COLOR_BOLD_BLUE,
  23         GIT_COLOR_BOLD_MAGENTA,
  24         GIT_COLOR_BOLD_CYAN,
  25         GIT_COLOR_RESET,
  26 };
  27
  28 enum {
  29         COLOR_BACKGROUND_OFFSET = 10,
  30         COLOR_FOREGROUND_ANSI = 30,
  31         COLOR_FOREGROUND_RGB = 38,
  32         COLOR_FOREGROUND_256 = 38,
  33         COLOR_FOREGROUND_BRIGHT_ANSI = 90,
  34 };
  35
  36 /* Ignore the RESET at the end when giving the size */
  37 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
  38
  39 /* An individual foreground or background color. */
  40 struct color {
  41         enum {
  42                 COLOR_UNSPECIFIED = 0,
  43                 COLOR_NORMAL,
  44                 COLOR_ANSI, /* basic 0-7 ANSI colors + "default" (value = 9) */
  45                 COLOR_256,
  46                 COLOR_RGB
  47         } type;
  48         /* The numeric value for ANSI and 256-color modes */
  49         unsigned char value;
  50         /* 24-bit RGB color values */
  51         unsigned char red, green, blue;
  52 };
  53
  54 /*
  55  * "word" is a buffer of length "len"; does it match the NUL-terminated
  56  * "match" exactly?
  57  */
  58 static int match_word(const char *word, int len, const char *match)
  59 {
  60         return !strncasecmp(word, match, len) && !match[len];
  61 }
  62
  63 static int get_hex_color(const char *in, unsigned char *out)
  64 {
  65         unsigned int val;
  66         val = (hexval(in[0]) << 4) | hexval(in[1]);
  67         if (val & ~0xff)
  68                 return -1;
  69         *out = val;
  70         return 0;
  71 }
  72
  73 /*
  74  * If an ANSI color is recognized in "name", fill "out" and return 0.
  75  * Otherwise, leave out unchanged and return -1.
  76  */
  77 static int parse_ansi_color(struct color *out, const char *name, int len)
  78 {
  79         /* Positions in array must match ANSI color codes */
  80         static const char * const color_names[] = {
  81                 "black", "red", "green", "yellow",
  82                 "blue", "magenta", "cyan", "white"
  83         };
  84         int i;
  85         int color_offset = COLOR_FOREGROUND_ANSI;
  86
  87         if (match_word(name, len, "default")) {
  88                 /*
  89                  * Restores to the terminal's default color, which may not be
  90                  * the same as explicitly setting "white" or "black".
  91                  *
  92                  * ECMA-48 - Control Functions \
  93                  *  for Coded Character Sets, 5th edition (June 1991):
  94                  * > 39 default display colour (implementation-defined)
  95                  * > 49 default background colour (implementation-defined)
  96                  *
  97                  * Although not supported /everywhere/--according to terminfo,
  98                  * some terminals define "op" (original pair) as a blunt
  99                  * "set to white on black", or even "send full SGR reset"--
 100                  * it's standard and well-supported enough that if a user
 101                  * asks for it in their config this will do the right thing.
 102                  */
 103                 out->type = COLOR_ANSI;
 104                 out->value = 9 + color_offset;
 105                 return 0;
 106         }
 107
 108         if (strncasecmp(name, "bright", 6) == 0) {
 109                 color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
 110                 name += 6;
 111                 len -= 6;
 112         }
 113         for (i = 0; i < ARRAY_SIZE(color_names); i++) {
 114                 if (match_word(name, len, color_names[i])) {
 115                         out->type = COLOR_ANSI;
 116                         out->value = i + color_offset;
 117                         return 0;
 118                 }
 119         }
 120         return -1;
 121 }
 122
 123 static int parse_color(struct color *out, const char *name, int len)
 124 {
 125         char *end;
 126         long val;
 127
 128         /* First try the special word "normal"... */
 129         if (match_word(name, len, "normal")) {
 130                 out->type = COLOR_NORMAL;
 131                 return 0;
 132         }
 133
 134         /* Try a 24-bit RGB value */
 135         if (len == 7 && name[0] == '#') {
 136                 if (!get_hex_color(name + 1, &out->red) &&
 137                     !get_hex_color(name + 3, &out->green) &&
 138                     !get_hex_color(name + 5, &out->blue)) {
 139                         out->type = COLOR_RGB;
 140                         return 0;
 141                 }
 142         }
 143
 144         /* Then pick from our human-readable color names... */
 145         if (parse_ansi_color(out, name, len) == 0) {
 146                 return 0;
 147         }
 148
 149         /* And finally try a literal 256-color-mode number */
 150         val = strtol(name, &end, 10);
 151         if (end - name == len) {
 152                 /*
 153                  * Allow "-1" as an alias for "normal", but other negative
 154                  * numbers are bogus.
 155                  */
 156                 if (val < -1)
 157                         ; /* fall through to error */
 158                 else if (val < 0) {
 159                         out->type = COLOR_NORMAL;
 160                         return 0;
 161                 /* Rewrite 0-7 as more-portable standard colors. */
 162                 } else if (val < 8) {
 163                         out->type = COLOR_ANSI;
 164                         out->value = val + COLOR_FOREGROUND_ANSI;
 165                         return 0;
 166                 /* Rewrite 8-15 as more-portable aixterm colors. */
 167                 } else if (val < 16) {
 168                         out->type = COLOR_ANSI;
 169                         out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
 170                         return 0;
 171                 } else if (val < 256) {
 172                         out->type = COLOR_256;
 173                         out->value = val;
 174                         return 0;
 175                 }
 176         }
 177
 178         return -1;
 179 }
 180
 181 static int parse_attr(const char *name, size_t len)
 182 {
 183         static const struct {
 184                 const char *name;
 185                 size_t len;
 186                 int val, neg;
 187         } attrs[] = {
 188 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
 189                 ATTR("bold",      1, 22),
 190                 ATTR("dim",       2, 22),
 191                 ATTR("italic",    3, 23),
 192                 ATTR("ul",        4, 24),
 193                 ATTR("blink",     5, 25),
 194                 ATTR("reverse",   7, 27),
 195                 ATTR("strike",    9, 29)
 196 #undef ATTR
 197         };
 198         int negate = 0;
 199         int i;
 200
 201         if (skip_prefix_mem(name, len, "no", &name, &len)) {
 202                 skip_prefix_mem(name, len, "-", &name, &len);
 203                 negate = 1;
 204         }
 205
 206         for (i = 0; i < ARRAY_SIZE(attrs); i++) {
 207                 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
 208                         return negate ? attrs[i].neg : attrs[i].val;
 209         }
 210         return -1;
 211 }
 212
 213 int color_parse(const char *value, char *dst)
 214 {
 215         return color_parse_mem(value, strlen(value), dst);
 216 }
 217
 218 /*
 219  * Write the ANSI color codes for "c" to "out"; the string should
 220  * already have the ANSI escape code in it. "out" should have enough
 221  * space in it to fit any color.
 222  */
 223 static char *color_output(char *out, int len, const struct color *c, int background)
 224 {
 225         int offset = 0;
 226
 227         if (background)
 228                 offset = COLOR_BACKGROUND_OFFSET;
 229         switch (c->type) {
 230         case COLOR_UNSPECIFIED:
 231         case COLOR_NORMAL:
 232                 break;
 233         case COLOR_ANSI:
 234                 out += xsnprintf(out, len, "%d", c->value + offset);
 235                 break;
 236         case COLOR_256:
 237                 out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
 238                                  c->value);
 239                 break;
 240         case COLOR_RGB:
 241                 out += xsnprintf(out, len, "%d;2;%d;%d;%d",
 242                                  COLOR_FOREGROUND_RGB + offset,
 243                                  c->red, c->green, c->blue);
 244                 break;
 245         }
 246         return out;
 247 }
 248
 249 static int color_empty(const struct color *c)
 250 {
 251         return c->type <= COLOR_NORMAL;
 252 }
 253
 254 int color_parse_mem(const char *value, int value_len, char *dst)
 255 {
 256         const char *ptr = value;
 257         int len = value_len;
 258         char *end = dst + COLOR_MAXLEN;
 259         unsigned int has_reset = 0;
 260         unsigned int attr = 0;
 261         struct color fg = { COLOR_UNSPECIFIED };
 262         struct color bg = { COLOR_UNSPECIFIED };
 263
 264         while (len > 0 && isspace(*ptr)) {
 265                 ptr++;
 266                 len--;
 267         }
 268
 269         if (!len) {
 270                 dst[0] = '\0';
 271                 return 0;
 272         }
 273
 274         /* [reset] [fg [bg]] [attr]... */
 275         while (len > 0) {
 276                 const char *word = ptr;
 277                 struct color c = { COLOR_UNSPECIFIED };
 278                 int val, wordlen = 0;
 279
 280                 while (len > 0 && !isspace(word[wordlen])) {
 281                         wordlen++;
 282                         len--;
 283                 }
 284
 285                 ptr = word + wordlen;
 286                 while (len > 0 && isspace(*ptr)) {
 287                         ptr++;
 288                         len--;
 289                 }
 290
 291                 if (match_word(word, wordlen, "reset")) {
 292                         has_reset = 1;
 293                         continue;
 294                 }
 295
 296                 if (!parse_color(&c, word, wordlen)) {
 297                         if (fg.type == COLOR_UNSPECIFIED) {
 298                                 fg = c;
 299                                 continue;
 300                         }
 301                         if (bg.type == COLOR_UNSPECIFIED) {
 302                                 bg = c;
 303                                 continue;
 304                         }
 305                         goto bad;
 306                 }
 307                 val = parse_attr(word, wordlen);
 308                 if (0 <= val)
 309                         attr |= (1 << val);
 310                 else
 311                         goto bad;
 312         }
 313
 314 #undef OUT
 315 #define OUT(x) do { \
 316         if (dst == end) \
 317                 BUG("color parsing ran out of space"); \
 318         *dst++ = (x); \
 319 } while(0)
 320
 321         if (has_reset || attr || !color_empty(&fg) || !color_empty(&bg)) {
 322                 int sep = 0;
 323                 int i;
 324
 325                 OUT('\033');
 326                 OUT('[');
 327
 328                 if (has_reset)
 329                         sep++;
 330
 331                 for (i = 0; attr; i++) {
 332                         unsigned bit = (1 << i);
 333                         if (!(attr & bit))
 334                                 continue;
 335                         attr &= ~bit;
 336                         if (sep++)
 337                                 OUT(';');
 338                         dst += xsnprintf(dst, end - dst, "%d", i);
 339                 }
 340                 if (!color_empty(&fg)) {
 341                         if (sep++)
 342                                 OUT(';');
 343                         dst = color_output(dst, end - dst, &fg, 0);
 344                 }
 345                 if (!color_empty(&bg)) {
 346                         if (sep++)
 347                                 OUT(';');
 348                         dst = color_output(dst, end - dst, &bg, 1);
 349                 }
 350                 OUT('m');
 351         }
 352         OUT(0);
 353         return 0;
 354 bad:
 355         return error(_("invalid color value: %.*s"), value_len, value);
 356 #undef OUT
 357 }
 358
 359 int git_config_colorbool(const char *var, const char *value)
 360 {
 361         if (value) {
 362                 if (!strcasecmp(value, "never"))
 363                         return 0;
 364                 if (!strcasecmp(value, "always"))
 365                         return 1;
 366                 if (!strcasecmp(value, "auto"))
 367                         return GIT_COLOR_AUTO;
 368         }
 369
 370         if (!var)
 371                 return -1;
 372
 373         /* Missing or explicit false to turn off colorization */
 374         if (!git_config_bool(var, value))
 375                 return 0;
 376
 377         /* any normal truth value defaults to 'auto' */
 378         return GIT_COLOR_AUTO;
 379 }
 380
 381 static int check_auto_color(int fd)
 382 {
 383         static int color_stderr_is_tty = -1;
 384         int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
 385         if (*is_tty_p < 0)
 386                 *is_tty_p = isatty(fd);
 387         if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
 388                 if (!is_terminal_dumb())
 389                         return 1;
 390         }
 391         return 0;
 392 }
 393
 394 int want_color_fd(int fd, int var)
 395 {
 396         /*
 397          * NEEDSWORK: This function is sometimes used from multiple threads, and
 398          * we end up using want_auto racily. That "should not matter" since
 399          * we always write the same value, but it's still wrong. This function
 400          * is listed in .tsan-suppressions for the time being.
 401          */
 402
 403         static int want_auto[3] = { -1, -1, -1 };
 404
 405         if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
 406                 BUG("file descriptor out of range: %d", fd);
 407
 408         if (var < 0)
 409                 var = git_use_color_default;
 410
 411         if (var == GIT_COLOR_AUTO) {
 412                 if (want_auto[fd] < 0)
 413                         want_auto[fd] = check_auto_color(fd);
 414                 return want_auto[fd];
 415         }
 416         return var;
 417 }
 418
 419 int git_color_config(const char *var, const char *value, void *cb UNUSED)
 420 {
 421         if (!strcmp(var, "color.ui")) {
 422                 git_use_color_default = git_config_colorbool(var, value);
 423                 return 0;
 424         }
 425
 426         return 0;
 427 }
 428
 429 int git_color_default_config(const char *var, const char *value, void *cb)
 430 {
 431         if (git_color_config(var, value, cb) < 0)
 432                 return -1;
 433
 434         return git_default_config(var, value, cb);
 435 }
 436
 437 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
 438 {
 439         if (*color)
 440                 fprintf(fp, "%s", color);
 441         fprintf(fp, "%s", sb->buf);
 442         if (*color)
 443                 fprintf(fp, "%s", GIT_COLOR_RESET);
 444 }
 445
 446 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
 447                 va_list args, const char *trail)
 448 {
 449         int r = 0;
 450
 451         if (*color)
 452                 r += fprintf(fp, "%s", color);
 453         r += vfprintf(fp, fmt, args);
 454         if (*color)
 455                 r += fprintf(fp, "%s", GIT_COLOR_RESET);
 456         if (trail)
 457                 r += fprintf(fp, "%s", trail);
 458         return r;
 459 }
 460
 461 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
 462 {
 463         va_list args;
 464         int r;
 465         va_start(args, fmt);
 466         r = color_vfprintf(fp, color, fmt, args, NULL);
 467         va_end(args);
 468         return r;
 469 }
 470
 471 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 472 {
 473         va_list args;
 474         int r;
 475         va_start(args, fmt);
 476         r = color_vfprintf(fp, color, fmt, args, "\n");
 477         va_end(args);
 478         return r;
 479 }
 480
 481 int color_is_nil(const char *c)
 482 {
 483         return !strcmp(c, "NIL");
 484 }