color.c

   1 #include "git-compat-util.h"
   2 #include "config.h"
   3 #include "color.h"
   4 #include "editor.h"
   5 #include "gettext.h"
   6 #include "hex-ll.h"
   7 #include "pager.h"
   8 #include "strbuf.h"
   9
  10 static int git_use_color_default = GIT_COLOR_AUTO;
  11 int color_stdout_is_tty = -1;
  12
  13 /*
  14  * The list of available column colors.
  15  */
  16 const char *column_colors_ansi[] = {
  17         GIT_COLOR_RED,
  18         GIT_COLOR_GREEN,
  19         GIT_COLOR_YELLOW,
  20         GIT_COLOR_BLUE,
  21         GIT_COLOR_MAGENTA,
  22         GIT_COLOR_CYAN,
  23         GIT_COLOR_BOLD_RED,
  24         GIT_COLOR_BOLD_GREEN,
  25         GIT_COLOR_BOLD_YELLOW,
  26         GIT_COLOR_BOLD_BLUE,
  27         GIT_COLOR_BOLD_MAGENTA,
  28         GIT_COLOR_BOLD_CYAN,
  29         GIT_COLOR_RESET,
  30 };
  31
  32 enum {
  33         COLOR_BACKGROUND_OFFSET = 10,
  34         COLOR_FOREGROUND_ANSI = 30,
  35         COLOR_FOREGROUND_RGB = 38,
  36         COLOR_FOREGROUND_256 = 38,
  37         COLOR_FOREGROUND_BRIGHT_ANSI = 90,
  38 };
  39
  40 /* Ignore the RESET at the end when giving the size */
  41 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
  42
  43 /* An individual foreground or background color. */
  44 struct color {
  45         enum {
  46                 COLOR_UNSPECIFIED = 0,
  47                 COLOR_NORMAL,
  48                 COLOR_ANSI, /* basic 0-7 ANSI colors + "default" (value = 9) */
  49                 COLOR_256,
  50                 COLOR_RGB
  51         } type;
  52         /* The numeric value for ANSI and 256-color modes */
  53         unsigned char value;
  54         /* 24-bit RGB color values */
  55         unsigned char red, green, blue;
  56 };
  57
  58 /*
  59  * "word" is a buffer of length "len"; does it match the NUL-terminated
  60  * "match" exactly?
  61  */
  62 static int match_word(const char *word, int len, const char *match)
  63 {
  64         return !strncasecmp(word, match, len) && !match[len];
  65 }
  66
  67 static int get_hex_color(const char **inp, int width, unsigned char *out)
  68 {
  69         const char *in = *inp;
  70         unsigned int val;
  71
  72         assert(width == 1 || width == 2);
  73         val = (hexval(in[0]) << 4) | hexval(in[width - 1]);
  74         if (val & ~0xff)
  75                 return -1;
  76         *inp += width;
  77         *out = val;
  78         return 0;
  79 }
  80
  81 /*
  82  * If an ANSI color is recognized in "name", fill "out" and return 0.
  83  * Otherwise, leave out unchanged and return -1.
  84  */
  85 static int parse_ansi_color(struct color *out, const char *name, int len)
  86 {
  87         /* Positions in array must match ANSI color codes */
  88         static const char * const color_names[] = {
  89                 "black", "red", "green", "yellow",
  90                 "blue", "magenta", "cyan", "white"
  91         };
  92         int i;
  93         int color_offset = COLOR_FOREGROUND_ANSI;
  94
  95         if (match_word(name, len, "default")) {
  96                 /*
  97                  * Restores to the terminal's default color, which may not be
  98                  * the same as explicitly setting "white" or "black".
  99                  *
 100                  * ECMA-48 - Control Functions \
 101                  *  for Coded Character Sets, 5th edition (June 1991):
 102                  * > 39 default display colour (implementation-defined)
 103                  * > 49 default background colour (implementation-defined)
 104                  *
 105                  * Although not supported /everywhere/--according to terminfo,
 106                  * some terminals define "op" (original pair) as a blunt
 107                  * "set to white on black", or even "send full SGR reset"--
 108                  * it's standard and well-supported enough that if a user
 109                  * asks for it in their config this will do the right thing.
 110                  */
 111                 out->type = COLOR_ANSI;
 112                 out->value = 9 + color_offset;
 113                 return 0;
 114         }
 115
 116         if (strncasecmp(name, "bright", 6) == 0) {
 117                 color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
 118                 name += 6;
 119                 len -= 6;
 120         }
 121         for (i = 0; i < ARRAY_SIZE(color_names); i++) {
 122                 if (match_word(name, len, color_names[i])) {
 123                         out->type = COLOR_ANSI;
 124                         out->value = i + color_offset;
 125                         return 0;
 126                 }
 127         }
 128         return -1;
 129 }
 130
 131 static int parse_color(struct color *out, const char *name, int len)
 132 {
 133         char *end;
 134         long val;
 135
 136         /* First try the special word "normal"... */
 137         if (match_word(name, len, "normal")) {
 138                 out->type = COLOR_NORMAL;
 139                 return 0;
 140         }
 141
 142         /* Try a 24- or 12-bit RGB value prefixed with '#' */
 143         if ((len == 7 || len == 4) && name[0] == '#') {
 144                 int width_per_color = (len == 7) ? 2 : 1;
 145                 const char *color = name + 1;
 146
 147                 if (!get_hex_color(&color, width_per_color, &out->red) &&
 148                     !get_hex_color(&color, width_per_color, &out->green) &&
 149                     !get_hex_color(&color, width_per_color, &out->blue)) {
 150                         out->type = COLOR_RGB;
 151                         return 0;
 152                 }
 153         }
 154
 155         /* Then pick from our human-readable color names... */
 156         if (parse_ansi_color(out, name, len) == 0) {
 157                 return 0;
 158         }
 159
 160         /* And finally try a literal 256-color-mode number */
 161         val = strtol(name, &end, 10);
 162         if (end - name == len) {
 163                 /*
 164                  * Allow "-1" as an alias for "normal", but other negative
 165                  * numbers are bogus.
 166                  */
 167                 if (val < -1)
 168                         ; /* fall through to error */
 169                 else if (val < 0) {
 170                         out->type = COLOR_NORMAL;
 171                         return 0;
 172                 /* Rewrite 0-7 as more-portable standard colors. */
 173                 } else if (val < 8) {
 174                         out->type = COLOR_ANSI;
 175                         out->value = val + COLOR_FOREGROUND_ANSI;
 176                         return 0;
 177                 /* Rewrite 8-15 as more-portable aixterm colors. */
 178                 } else if (val < 16) {
 179                         out->type = COLOR_ANSI;
 180                         out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
 181                         return 0;
 182                 } else if (val < 256) {
 183                         out->type = COLOR_256;
 184                         out->value = val;
 185                         return 0;
 186                 }
 187         }
 188
 189         return -1;
 190 }
 191
 192 static int parse_attr(const char *name, size_t len)
 193 {
 194         static const struct {
 195                 const char *name;
 196                 size_t len;
 197                 int val, neg;
 198         } attrs[] = {
 199 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
 200                 ATTR("bold",      1, 22),
 201                 ATTR("dim",       2, 22),
 202                 ATTR("italic",    3, 23),
 203                 ATTR("ul",        4, 24),
 204                 ATTR("blink",     5, 25),
 205                 ATTR("reverse",   7, 27),
 206                 ATTR("strike",    9, 29)
 207 #undef ATTR
 208         };
 209         int negate = 0;
 210         int i;
 211
 212         if (skip_prefix_mem(name, len, "no", &name, &len)) {
 213                 skip_prefix_mem(name, len, "-", &name, &len);
 214                 negate = 1;
 215         }
 216
 217         for (i = 0; i < ARRAY_SIZE(attrs); i++) {
 218                 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
 219                         return negate ? attrs[i].neg : attrs[i].val;
 220         }
 221         return -1;
 222 }
 223
 224 int color_parse(const char *value, char *dst)
 225 {
 226         return color_parse_mem(value, strlen(value), dst);
 227 }
 228
 229 /*
 230  * Write the ANSI color codes for "c" to "out"; the string should
 231  * already have the ANSI escape code in it. "out" should have enough
 232  * space in it to fit any color.
 233  */
 234 static char *color_output(char *out, int len, const struct color *c, int background)
 235 {
 236         int offset = 0;
 237
 238         if (background)
 239                 offset = COLOR_BACKGROUND_OFFSET;
 240         switch (c->type) {
 241         case COLOR_UNSPECIFIED:
 242         case COLOR_NORMAL:
 243                 break;
 244         case COLOR_ANSI:
 245                 out += xsnprintf(out, len, "%d", c->value + offset);
 246                 break;
 247         case COLOR_256:
 248                 out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
 249                                  c->value);
 250                 break;
 251         case COLOR_RGB:
 252                 out += xsnprintf(out, len, "%d;2;%d;%d;%d",
 253                                  COLOR_FOREGROUND_RGB + offset,
 254                                  c->red, c->green, c->blue);
 255                 break;
 256         }
 257         return out;
 258 }
 259
 260 static int color_empty(const struct color *c)
 261 {
 262         return c->type <= COLOR_NORMAL;
 263 }
 264
 265 int color_parse_mem(const char *value, int value_len, char *dst)
 266 {
 267         const char *ptr = value;
 268         int len = value_len;
 269         char *end = dst + COLOR_MAXLEN;
 270         unsigned int has_reset = 0;
 271         unsigned int attr = 0;
 272         struct color fg = { COLOR_UNSPECIFIED };
 273         struct color bg = { COLOR_UNSPECIFIED };
 274
 275         while (len > 0 && isspace(*ptr)) {
 276                 ptr++;
 277                 len--;
 278         }
 279
 280         if (!len) {
 281                 dst[0] = '\0';
 282                 return 0;
 283         }
 284
 285         /* [reset] [fg [bg]] [attr]... */
 286         while (len > 0) {
 287                 const char *word = ptr;
 288                 struct color c = { COLOR_UNSPECIFIED };
 289                 int val, wordlen = 0;
 290
 291                 while (len > 0 && !isspace(word[wordlen])) {
 292                         wordlen++;
 293                         len--;
 294                 }
 295
 296                 ptr = word + wordlen;
 297                 while (len > 0 && isspace(*ptr)) {
 298                         ptr++;
 299                         len--;
 300                 }
 301
 302                 if (match_word(word, wordlen, "reset")) {
 303                         has_reset = 1;
 304                         continue;
 305                 }
 306
 307                 if (!parse_color(&c, word, wordlen)) {
 308                         if (fg.type == COLOR_UNSPECIFIED) {
 309                                 fg = c;
 310                                 continue;
 311                         }
 312                         if (bg.type == COLOR_UNSPECIFIED) {
 313                                 bg = c;
 314                                 continue;
 315                         }
 316                         goto bad;
 317                 }
 318                 val = parse_attr(word, wordlen);
 319                 if (0 <= val)
 320                         attr |= (1 << val);
 321                 else
 322                         goto bad;
 323         }
 324
 325 #undef OUT
 326 #define OUT(x) do { \
 327         if (dst == end) \
 328                 BUG("color parsing ran out of space"); \
 329         *dst++ = (x); \
 330 } while(0)
 331
 332         if (has_reset || attr || !color_empty(&fg) || !color_empty(&bg)) {
 333                 int sep = 0;
 334                 int i;
 335
 336                 OUT('\033');
 337                 OUT('[');
 338
 339                 if (has_reset)
 340                         sep++;
 341
 342                 for (i = 0; attr; i++) {
 343                         unsigned bit = (1 << i);
 344                         if (!(attr & bit))
 345                                 continue;
 346                         attr &= ~bit;
 347                         if (sep++)
 348                                 OUT(';');
 349                         dst += xsnprintf(dst, end - dst, "%d", i);
 350                 }
 351                 if (!color_empty(&fg)) {
 352                         if (sep++)
 353                                 OUT(';');
 354                         dst = color_output(dst, end - dst, &fg, 0);
 355                 }
 356                 if (!color_empty(&bg)) {
 357                         if (sep++)
 358                                 OUT(';');
 359                         dst = color_output(dst, end - dst, &bg, 1);
 360                 }
 361                 OUT('m');
 362         }
 363         OUT(0);
 364         return 0;
 365 bad:
 366         return error(_("invalid color value: %.*s"), value_len, value);
 367 #undef OUT
 368 }
 369
 370 int git_config_colorbool(const char *var, const char *value)
 371 {
 372         if (value) {
 373                 if (!strcasecmp(value, "never"))
 374                         return 0;
 375                 if (!strcasecmp(value, "always"))
 376                         return 1;
 377                 if (!strcasecmp(value, "auto"))
 378                         return GIT_COLOR_AUTO;
 379         }
 380
 381         if (!var)
 382                 return -1;
 383
 384         /* Missing or explicit false to turn off colorization */
 385         if (!git_config_bool(var, value))
 386                 return 0;
 387
 388         /* any normal truth value defaults to 'auto' */
 389         return GIT_COLOR_AUTO;
 390 }
 391
 392 static int check_auto_color(int fd)
 393 {
 394         static int color_stderr_is_tty = -1;
 395         int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
 396         if (*is_tty_p < 0)
 397                 *is_tty_p = isatty(fd);
 398         if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
 399                 if (!is_terminal_dumb())
 400                         return 1;
 401         }
 402         return 0;
 403 }
 404
 405 int want_color_fd(int fd, int var)
 406 {
 407         /*
 408          * NEEDSWORK: This function is sometimes used from multiple threads, and
 409          * we end up using want_auto racily. That "should not matter" since
 410          * we always write the same value, but it's still wrong. This function
 411          * is listed in .tsan-suppressions for the time being.
 412          */
 413
 414         static int want_auto[3] = { -1, -1, -1 };
 415
 416         if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
 417                 BUG("file descriptor out of range: %d", fd);
 418
 419         if (var < 0)
 420                 var = git_use_color_default;
 421
 422         if (var == GIT_COLOR_AUTO) {
 423                 if (want_auto[fd] < 0)
 424                         want_auto[fd] = check_auto_color(fd);
 425                 return want_auto[fd];
 426         }
 427         return var;
 428 }
 429
 430 int git_color_config(const char *var, const char *value, void *cb UNUSED)
 431 {
 432         if (!strcmp(var, "color.ui")) {
 433                 git_use_color_default = git_config_colorbool(var, value);
 434                 return 0;
 435         }
 436
 437         return 0;
 438 }
 439
 440 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
 441 {
 442         if (*color)
 443                 fprintf(fp, "%s", color);
 444         fprintf(fp, "%s", sb->buf);
 445         if (*color)
 446                 fprintf(fp, "%s", GIT_COLOR_RESET);
 447 }
 448
 449 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
 450                 va_list args, const char *trail)
 451 {
 452         int r = 0;
 453
 454         if (*color)
 455                 r += fprintf(fp, "%s", color);
 456         r += vfprintf(fp, fmt, args);
 457         if (*color)
 458                 r += fprintf(fp, "%s", GIT_COLOR_RESET);
 459         if (trail)
 460                 r += fprintf(fp, "%s", trail);
 461         return r;
 462 }
 463
 464 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
 465 {
 466         va_list args;
 467         int r;
 468         va_start(args, fmt);
 469         r = color_vfprintf(fp, color, fmt, args, NULL);
 470         va_end(args);
 471         return r;
 472 }
 473
 474 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 475 {
 476         va_list args;
 477         int r;
 478         va_start(args, fmt);
 479         r = color_vfprintf(fp, color, fmt, args, "\n");
 480         va_end(args);
 481         return r;
 482 }
 483
 484 int color_is_nil(const char *c)
 485 {
 486         return !strcmp(c, "NIL");
 487 }