color.c

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