color.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "color.h"
   4 #include "gettext.h"
   5 #include "hex.h"
   6
   7 static int git_use_color_default = GIT_COLOR_AUTO;
   8 int color_stdout_is_tty = -1;
   9
  10 /*
  11  * The list of available column colors.
  12  */
  13 const char *column_colors_ansi[] = {
  14         GIT_COLOR_RED,
  15         GIT_COLOR_GREEN,
  16         GIT_COLOR_YELLOW,
  17         GIT_COLOR_BLUE,
  18         GIT_COLOR_MAGENTA,
  19         GIT_COLOR_CYAN,
  20         GIT_COLOR_BOLD_RED,
  21         GIT_COLOR_BOLD_GREEN,
  22         GIT_COLOR_BOLD_YELLOW,
  23         GIT_COLOR_BOLD_BLUE,
  24         GIT_COLOR_BOLD_MAGENTA,
  25         GIT_COLOR_BOLD_CYAN,
  26         GIT_COLOR_RESET,
  27 };
  28
  29 enum {
  30         COLOR_BACKGROUND_OFFSET = 10,
  31         COLOR_FOREGROUND_ANSI = 30,
  32         COLOR_FOREGROUND_RGB = 38,
  33         COLOR_FOREGROUND_256 = 38,
  34         COLOR_FOREGROUND_BRIGHT_ANSI = 90,
  35 };
  36
  37 /* Ignore the RESET at the end when giving the size */
  38 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
  39
  40 /* An individual foreground or background color. */
  41 struct color {
  42         enum {
  43                 COLOR_UNSPECIFIED = 0,
  44                 COLOR_NORMAL,
  45                 COLOR_ANSI, /* basic 0-7 ANSI colors + "default" (value = 9) */
  46                 COLOR_256,
  47                 COLOR_RGB
  48         } type;
  49         /* The numeric value for ANSI and 256-color modes */
  50         unsigned char value;
  51         /* 24-bit RGB color values */
  52         unsigned char red, green, blue;
  53 };
  54
  55 /*
  56  * "word" is a buffer of length "len"; does it match the NUL-terminated
  57  * "match" exactly?
  58  */
  59 static int match_word(const char *word, int len, const char *match)
  60 {
  61         return !strncasecmp(word, match, len) && !match[len];
  62 }
  63
  64 static int get_hex_color(const char *in, unsigned char *out)
  65 {
  66         unsigned int val;
  67         val = (hexval(in[0]) << 4) | hexval(in[1]);
  68         if (val & ~0xff)
  69                 return -1;
  70         *out = val;
  71         return 0;
  72 }
  73
  74 /*
  75  * If an ANSI color is recognized in "name", fill "out" and return 0.
  76  * Otherwise, leave out unchanged and return -1.
  77  */
  78 static int parse_ansi_color(struct color *out, const char *name, int len)
  79 {
  80         /* Positions in array must match ANSI color codes */
  81         static const char * const color_names[] = {
  82                 "black", "red", "green", "yellow",
  83                 "blue", "magenta", "cyan", "white"
  84         };
  85         int i;
  86         int color_offset = COLOR_FOREGROUND_ANSI;
  87
  88         if (match_word(name, len, "default")) {
  89                 /*
  90                  * Restores to the terminal's default color, which may not be
  91                  * the same as explicitly setting "white" or "black".
  92                  *
  93                  * ECMA-48 - Control Functions \
  94                  *  for Coded Character Sets, 5th edition (June 1991):
  95                  * > 39 default display colour (implementation-defined)
  96                  * > 49 default background colour (implementation-defined)
  97                  *
  98                  * Although not supported /everywhere/--according to terminfo,
  99                  * some terminals define "op" (original pair) as a blunt
 100                  * "set to white on black", or even "send full SGR reset"--
 101                  * it's standard and well-supported enough that if a user
 102                  * asks for it in their config this will do the right thing.
 103                  */
 104                 out->type = COLOR_ANSI;
 105                 out->value = 9 + color_offset;
 106                 return 0;
 107         }
 108
 109         if (strncasecmp(name, "bright", 6) == 0) {
 110                 color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
 111                 name += 6;
 112                 len -= 6;
 113         }
 114         for (i = 0; i < ARRAY_SIZE(color_names); i++) {
 115                 if (match_word(name, len, color_names[i])) {
 116                         out->type = COLOR_ANSI;
 117                         out->value = i + color_offset;
 118                         return 0;
 119                 }
 120         }
 121         return -1;
 122 }
 123
 124 static int parse_color(struct color *out, const char *name, int len)
 125 {
 126         char *end;
 127         long val;
 128
 129         /* First try the special word "normal"... */
 130         if (match_word(name, len, "normal")) {
 131                 out->type = COLOR_NORMAL;
 132                 return 0;
 133         }
 134
 135         /* Try a 24-bit RGB value */
 136         if (len == 7 && name[0] == '#') {
 137                 if (!get_hex_color(name + 1, &out->red) &&
 138                     !get_hex_color(name + 3, &out->green) &&
 139                     !get_hex_color(name + 5, &out->blue)) {
 140                         out->type = COLOR_RGB;
 141                         return 0;
 142                 }
 143         }
 144
 145         /* Then pick from our human-readable color names... */
 146         if (parse_ansi_color(out, name, len) == 0) {
 147                 return 0;
 148         }
 149
 150         /* And finally try a literal 256-color-mode number */
 151         val = strtol(name, &end, 10);
 152         if (end - name == len) {
 153                 /*
 154                  * Allow "-1" as an alias for "normal", but other negative
 155                  * numbers are bogus.
 156                  */
 157                 if (val < -1)
 158                         ; /* fall through to error */
 159                 else if (val < 0) {
 160                         out->type = COLOR_NORMAL;
 161                         return 0;
 162                 /* Rewrite 0-7 as more-portable standard colors. */
 163                 } else if (val < 8) {
 164                         out->type = COLOR_ANSI;
 165                         out->value = val + COLOR_FOREGROUND_ANSI;
 166                         return 0;
 167                 /* Rewrite 8-15 as more-portable aixterm colors. */
 168                 } else if (val < 16) {
 169                         out->type = COLOR_ANSI;
 170                         out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
 171                         return 0;
 172                 } else if (val < 256) {
 173                         out->type = COLOR_256;
 174                         out->value = val;
 175                         return 0;
 176                 }
 177         }
 178
 179         return -1;
 180 }
 181
 182 static int parse_attr(const char *name, size_t len)
 183 {
 184         static const struct {
 185                 const char *name;
 186                 size_t len;
 187                 int val, neg;
 188         } attrs[] = {
 189 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
 190                 ATTR("bold",      1, 22),
 191                 ATTR("dim",       2, 22),
 192                 ATTR("italic",    3, 23),
 193                 ATTR("ul",        4, 24),
 194                 ATTR("blink",     5, 25),
 195                 ATTR("reverse",   7, 27),
 196                 ATTR("strike",    9, 29)
 197 #undef ATTR
 198         };
 199         int negate = 0;
 200         int i;
 201
 202         if (skip_prefix_mem(name, len, "no", &name, &len)) {
 203                 skip_prefix_mem(name, len, "-", &name, &len);
 204                 negate = 1;
 205         }
 206
 207         for (i = 0; i < ARRAY_SIZE(attrs); i++) {
 208                 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
 209                         return negate ? attrs[i].neg : attrs[i].val;
 210         }
 211         return -1;
 212 }
 213
 214 int color_parse(const char *value, char *dst)
 215 {
 216         return color_parse_mem(value, strlen(value), dst);
 217 }
 218
 219 /*
 220  * Write the ANSI color codes for "c" to "out"; the string should
 221  * already have the ANSI escape code in it. "out" should have enough
 222  * space in it to fit any color.
 223  */
 224 static char *color_output(char *out, int len, const struct color *c, int background)
 225 {
 226         int offset = 0;
 227
 228         if (background)
 229                 offset = COLOR_BACKGROUND_OFFSET;
 230         switch (c->type) {
 231         case COLOR_UNSPECIFIED:
 232         case COLOR_NORMAL:
 233                 break;
 234         case COLOR_ANSI:
 235                 out += xsnprintf(out, len, "%d", c->value + offset);
 236                 break;
 237         case COLOR_256:
 238                 out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
 239                                  c->value);
 240                 break;
 241         case COLOR_RGB:
 242                 out += xsnprintf(out, len, "%d;2;%d;%d;%d",
 243                                  COLOR_FOREGROUND_RGB + offset,
 244                                  c->red, c->green, c->blue);
 245                 break;
 246         }
 247         return out;
 248 }
 249
 250 static int color_empty(const struct color *c)
 251 {
 252         return c->type <= COLOR_NORMAL;
 253 }
 254
 255 int color_parse_mem(const char *value, int value_len, char *dst)
 256 {
 257         const char *ptr = value;
 258         int len = value_len;
 259         char *end = dst + COLOR_MAXLEN;
 260         unsigned int has_reset = 0;
 261         unsigned int attr = 0;
 262         struct color fg = { COLOR_UNSPECIFIED };
 263         struct color bg = { COLOR_UNSPECIFIED };
 264
 265         while (len > 0 && isspace(*ptr)) {
 266                 ptr++;
 267                 len--;
 268         }
 269
 270         if (!len) {
 271                 dst[0] = '\0';
 272                 return 0;
 273         }
 274
 275         /* [reset] [fg [bg]] [attr]... */
 276         while (len > 0) {
 277                 const char *word = ptr;
 278                 struct color c = { COLOR_UNSPECIFIED };
 279                 int val, wordlen = 0;
 280
 281                 while (len > 0 && !isspace(word[wordlen])) {
 282                         wordlen++;
 283                         len--;
 284                 }
 285
 286                 ptr = word + wordlen;
 287                 while (len > 0 && isspace(*ptr)) {
 288                         ptr++;
 289                         len--;
 290                 }
 291
 292                 if (match_word(word, wordlen, "reset")) {
 293                         has_reset = 1;
 294                         continue;
 295                 }
 296
 297                 if (!parse_color(&c, word, wordlen)) {
 298                         if (fg.type == COLOR_UNSPECIFIED) {
 299                                 fg = c;
 300                                 continue;
 301                         }
 302                         if (bg.type == COLOR_UNSPECIFIED) {
 303                                 bg = c;
 304                                 continue;
 305                         }
 306                         goto bad;
 307                 }
 308                 val = parse_attr(word, wordlen);
 309                 if (0 <= val)
 310                         attr |= (1 << val);
 311                 else
 312                         goto bad;
 313         }
 314
 315 #undef OUT
 316 #define OUT(x) do { \
 317         if (dst == end) \
 318                 BUG("color parsing ran out of space"); \
 319         *dst++ = (x); \
 320 } while(0)
 321
 322         if (has_reset || attr || !color_empty(&fg) || !color_empty(&bg)) {
 323                 int sep = 0;
 324                 int i;
 325
 326                 OUT('\033');
 327                 OUT('[');
 328
 329                 if (has_reset)
 330                         sep++;
 331
 332                 for (i = 0; attr; i++) {
 333                         unsigned bit = (1 << i);
 334                         if (!(attr & bit))
 335                                 continue;
 336                         attr &= ~bit;
 337                         if (sep++)
 338                                 OUT(';');
 339                         dst += xsnprintf(dst, end - dst, "%d", i);
 340                 }
 341                 if (!color_empty(&fg)) {
 342                         if (sep++)
 343                                 OUT(';');
 344                         dst = color_output(dst, end - dst, &fg, 0);
 345                 }
 346                 if (!color_empty(&bg)) {
 347                         if (sep++)
 348                                 OUT(';');
 349                         dst = color_output(dst, end - dst, &bg, 1);
 350                 }
 351                 OUT('m');
 352         }
 353         OUT(0);
 354         return 0;
 355 bad:
 356         return error(_("invalid color value: %.*s"), value_len, value);
 357 #undef OUT
 358 }
 359
 360 int git_config_colorbool(const char *var, const char *value)
 361 {
 362         if (value) {
 363                 if (!strcasecmp(value, "never"))
 364                         return 0;
 365                 if (!strcasecmp(value, "always"))
 366                         return 1;
 367                 if (!strcasecmp(value, "auto"))
 368                         return GIT_COLOR_AUTO;
 369         }
 370
 371         if (!var)
 372                 return -1;
 373
 374         /* Missing or explicit false to turn off colorization */
 375         if (!git_config_bool(var, value))
 376                 return 0;
 377
 378         /* any normal truth value defaults to 'auto' */
 379         return GIT_COLOR_AUTO;
 380 }
 381
 382 static int check_auto_color(int fd)
 383 {
 384         static int color_stderr_is_tty = -1;
 385         int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
 386         if (*is_tty_p < 0)
 387                 *is_tty_p = isatty(fd);
 388         if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
 389                 if (!is_terminal_dumb())
 390                         return 1;
 391         }
 392         return 0;
 393 }
 394
 395 int want_color_fd(int fd, int var)
 396 {
 397         /*
 398          * NEEDSWORK: This function is sometimes used from multiple threads, and
 399          * we end up using want_auto racily. That "should not matter" since
 400          * we always write the same value, but it's still wrong. This function
 401          * is listed in .tsan-suppressions for the time being.
 402          */
 403
 404         static int want_auto[3] = { -1, -1, -1 };
 405
 406         if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
 407                 BUG("file descriptor out of range: %d", fd);
 408
 409         if (var < 0)
 410                 var = git_use_color_default;
 411
 412         if (var == GIT_COLOR_AUTO) {
 413                 if (want_auto[fd] < 0)
 414                         want_auto[fd] = check_auto_color(fd);
 415                 return want_auto[fd];
 416         }
 417         return var;
 418 }
 419
 420 int git_color_config(const char *var, const char *value, void *cb UNUSED)
 421 {
 422         if (!strcmp(var, "color.ui")) {
 423                 git_use_color_default = git_config_colorbool(var, value);
 424                 return 0;
 425         }
 426
 427         return 0;
 428 }
 429
 430 int git_color_default_config(const char *var, const char *value, void *cb)
 431 {
 432         if (git_color_config(var, value, cb) < 0)
 433                 return -1;
 434
 435         return git_default_config(var, value, cb);
 436 }
 437
 438 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
 439 {
 440         if (*color)
 441                 fprintf(fp, "%s", color);
 442         fprintf(fp, "%s", sb->buf);
 443         if (*color)
 444                 fprintf(fp, "%s", GIT_COLOR_RESET);
 445 }
 446
 447 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
 448                 va_list args, const char *trail)
 449 {
 450         int r = 0;
 451
 452         if (*color)
 453                 r += fprintf(fp, "%s", color);
 454         r += vfprintf(fp, fmt, args);
 455         if (*color)
 456                 r += fprintf(fp, "%s", GIT_COLOR_RESET);
 457         if (trail)
 458                 r += fprintf(fp, "%s", trail);
 459         return r;
 460 }
 461
 462 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
 463 {
 464         va_list args;
 465         int r;
 466         va_start(args, fmt);
 467         r = color_vfprintf(fp, color, fmt, args, NULL);
 468         va_end(args);
 469         return r;
 470 }
 471
 472 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 473 {
 474         va_list args;
 475         int r;
 476         va_start(args, fmt);
 477         r = color_vfprintf(fp, color, fmt, args, "\n");
 478         va_end(args);
 479         return r;
 480 }
 481
 482 int color_is_nil(const char *c)
 483 {
 484         return !strcmp(c, "NIL");
 485 }