color.c

   1 #define DISABLE_SIGN_COMPARE_WARNINGS
   2
   3 #include "git-compat-util.h"
   4 #include "config.h"
   5 #include "color.h"
   6 #include "editor.h"
   7 #include "gettext.h"
   8 #include "hex-ll.h"
   9 #include "pager.h"
  10 #include "strbuf.h"
  11
  12 static int git_use_color_default = GIT_COLOR_AUTO;
  13 int color_stdout_is_tty = -1;
  14
  15 /*
  16  * The list of available column colors.
  17  */
  18 const char *column_colors_ansi[] = {
  19         GIT_COLOR_RED,
  20         GIT_COLOR_GREEN,
  21         GIT_COLOR_YELLOW,
  22         GIT_COLOR_BLUE,
  23         GIT_COLOR_MAGENTA,
  24         GIT_COLOR_CYAN,
  25         GIT_COLOR_BOLD_RED,
  26         GIT_COLOR_BOLD_GREEN,
  27         GIT_COLOR_BOLD_YELLOW,
  28         GIT_COLOR_BOLD_BLUE,
  29         GIT_COLOR_BOLD_MAGENTA,
  30         GIT_COLOR_BOLD_CYAN,
  31         GIT_COLOR_RESET,
  32 };
  33
  34 enum {
  35         COLOR_BACKGROUND_OFFSET = 10,
  36         COLOR_FOREGROUND_ANSI = 30,
  37         COLOR_FOREGROUND_RGB = 38,
  38         COLOR_FOREGROUND_256 = 38,
  39         COLOR_FOREGROUND_BRIGHT_ANSI = 90,
  40 };
  41
  42 /* Ignore the RESET at the end when giving the size */
  43 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
  44
  45 /* An individual foreground or background color. */
  46 struct color {
  47         enum {
  48                 COLOR_UNSPECIFIED = 0,
  49                 COLOR_NORMAL,
  50                 COLOR_ANSI, /* basic 0-7 ANSI colors + "default" (value = 9) */
  51                 COLOR_256,
  52                 COLOR_RGB
  53         } type;
  54         /* The numeric value for ANSI and 256-color modes */
  55         unsigned char value;
  56         /* 24-bit RGB color values */
  57         unsigned char red, green, blue;
  58 };
  59
  60 /*
  61  * "word" is a buffer of length "len"; does it match the NUL-terminated
  62  * "match" exactly?
  63  */
  64 static int match_word(const char *word, int len, const char *match)
  65 {
  66         return !strncasecmp(word, match, len) && !match[len];
  67 }
  68
  69 static int get_hex_color(const char **inp, int width, unsigned char *out)
  70 {
  71         const char *in = *inp;
  72         unsigned int val;
  73
  74         assert(width == 1 || width == 2);
  75         val = (hexval(in[0]) << 4) | hexval(in[width - 1]);
  76         if (val & ~0xff)
  77                 return -1;
  78         *inp += width;
  79         *out = val;
  80         return 0;
  81 }
  82
  83 /*
  84  * If an ANSI color is recognized in "name", fill "out" and return 0.
  85  * Otherwise, leave out unchanged and return -1.
  86  */
  87 static int parse_ansi_color(struct color *out, const char *name, int len)
  88 {
  89         /* Positions in array must match ANSI color codes */
  90         static const char * const color_names[] = {
  91                 "black", "red", "green", "yellow",
  92                 "blue", "magenta", "cyan", "white"
  93         };
  94         int i;
  95         int color_offset = COLOR_FOREGROUND_ANSI;
  96
  97         if (match_word(name, len, "default")) {
  98                 /*
  99                  * Restores to the terminal's default color, which may not be
 100                  * the same as explicitly setting "white" or "black".
 101                  *
 102                  * ECMA-48 - Control Functions \
 103                  *  for Coded Character Sets, 5th edition (June 1991):
 104                  * > 39 default display colour (implementation-defined)
 105                  * > 49 default background colour (implementation-defined)
 106                  *
 107                  * Although not supported /everywhere/--according to terminfo,
 108                  * some terminals define "op" (original pair) as a blunt
 109                  * "set to white on black", or even "send full SGR reset"--
 110                  * it's standard and well-supported enough that if a user
 111                  * asks for it in their config this will do the right thing.
 112                  */
 113                 out->type = COLOR_ANSI;
 114                 out->value = 9 + color_offset;
 115                 return 0;
 116         }
 117
 118         if (strncasecmp(name, "bright", 6) == 0) {
 119                 color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
 120                 name += 6;
 121                 len -= 6;
 122         }
 123         for (i = 0; i < ARRAY_SIZE(color_names); i++) {
 124                 if (match_word(name, len, color_names[i])) {
 125                         out->type = COLOR_ANSI;
 126                         out->value = i + color_offset;
 127                         return 0;
 128                 }
 129         }
 130         return -1;
 131 }
 132
 133 static int parse_color(struct color *out, const char *name, int len)
 134 {
 135         char *end;
 136         long val;
 137
 138         /* First try the special word "normal"... */
 139         if (match_word(name, len, "normal")) {
 140                 out->type = COLOR_NORMAL;
 141                 return 0;
 142         }
 143
 144         /* Try a 24- or 12-bit RGB value prefixed with '#' */
 145         if ((len == 7 || len == 4) && name[0] == '#') {
 146                 int width_per_color = (len == 7) ? 2 : 1;
 147                 const char *color = name + 1;
 148
 149                 if (!get_hex_color(&color, width_per_color, &out->red) &&
 150                     !get_hex_color(&color, width_per_color, &out->green) &&
 151                     !get_hex_color(&color, width_per_color, &out->blue)) {
 152                         out->type = COLOR_RGB;
 153                         return 0;
 154                 }
 155         }
 156
 157         /* Then pick from our human-readable color names... */
 158         if (parse_ansi_color(out, name, len) == 0) {
 159                 return 0;
 160         }
 161
 162         /* And finally try a literal 256-color-mode number */
 163         val = strtol(name, &end, 10);
 164         if (end - name == len) {
 165                 /*
 166                  * Allow "-1" as an alias for "normal", but other negative
 167                  * numbers are bogus.
 168                  */
 169                 if (val < -1)
 170                         ; /* fall through to error */
 171                 else if (val < 0) {
 172                         out->type = COLOR_NORMAL;
 173                         return 0;
 174                 /* Rewrite 0-7 as more-portable standard colors. */
 175                 } else if (val < 8) {
 176                         out->type = COLOR_ANSI;
 177                         out->value = val + COLOR_FOREGROUND_ANSI;
 178                         return 0;
 179                 /* Rewrite 8-15 as more-portable aixterm colors. */
 180                 } else if (val < 16) {
 181                         out->type = COLOR_ANSI;
 182                         out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
 183                         return 0;
 184                 } else if (val < 256) {
 185                         out->type = COLOR_256;
 186                         out->value = val;
 187                         return 0;
 188                 }
 189         }
 190
 191         return -1;
 192 }
 193
 194 static int parse_attr(const char *name, size_t len)
 195 {
 196         static const struct {
 197                 const char *name;
 198                 size_t len;
 199                 int val, neg;
 200         } attrs[] = {
 201 #define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
 202                 ATTR("bold",      1, 22),
 203                 ATTR("dim",       2, 22),
 204                 ATTR("italic",    3, 23),
 205                 ATTR("ul",        4, 24),
 206                 ATTR("blink",     5, 25),
 207                 ATTR("reverse",   7, 27),
 208                 ATTR("strike",    9, 29)
 209 #undef ATTR
 210         };
 211         int negate = 0;
 212         int i;
 213
 214         if (skip_prefix_mem(name, len, "no", &name, &len)) {
 215                 skip_prefix_mem(name, len, "-", &name, &len);
 216                 negate = 1;
 217         }
 218
 219         for (i = 0; i < ARRAY_SIZE(attrs); i++) {
 220                 if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
 221                         return negate ? attrs[i].neg : attrs[i].val;
 222         }
 223         return -1;
 224 }
 225
 226 int color_parse(const char *value, char *dst)
 227 {
 228         return color_parse_mem(value, strlen(value), dst);
 229 }
 230
 231 /*
 232  * Write the ANSI color codes for "c" to "out"; the string should
 233  * already have the ANSI escape code in it. "out" should have enough
 234  * space in it to fit any color.
 235  */
 236 static char *color_output(char *out, int len, const struct color *c, int background)
 237 {
 238         int offset = 0;
 239
 240         if (background)
 241                 offset = COLOR_BACKGROUND_OFFSET;
 242         switch (c->type) {
 243         case COLOR_UNSPECIFIED:
 244         case COLOR_NORMAL:
 245                 break;
 246         case COLOR_ANSI:
 247                 out += xsnprintf(out, len, "%d", c->value + offset);
 248                 break;
 249         case COLOR_256:
 250                 out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
 251                                  c->value);
 252                 break;
 253         case COLOR_RGB:
 254                 out += xsnprintf(out, len, "%d;2;%d;%d;%d",
 255                                  COLOR_FOREGROUND_RGB + offset,
 256                                  c->red, c->green, c->blue);
 257                 break;
 258         }
 259         return out;
 260 }
 261
 262 static int color_empty(const struct color *c)
 263 {
 264         return c->type <= COLOR_NORMAL;
 265 }
 266
 267 int color_parse_mem(const char *value, int value_len, char *dst)
 268 {
 269         const char *ptr = value;
 270         int len = value_len;
 271         char *end = dst + COLOR_MAXLEN;
 272         unsigned int has_reset = 0;
 273         unsigned int attr = 0;
 274         struct color fg = { COLOR_UNSPECIFIED };
 275         struct color bg = { COLOR_UNSPECIFIED };
 276
 277         while (len > 0 && isspace(*ptr)) {
 278                 ptr++;
 279                 len--;
 280         }
 281
 282         if (!len) {
 283                 dst[0] = '\0';
 284                 return 0;
 285         }
 286
 287         /* [reset] [fg [bg]] [attr]... */
 288         while (len > 0) {
 289                 const char *word = ptr;
 290                 struct color c = { COLOR_UNSPECIFIED };
 291                 int val, wordlen = 0;
 292
 293                 while (len > 0 && !isspace(word[wordlen])) {
 294                         wordlen++;
 295                         len--;
 296                 }
 297
 298                 ptr = word + wordlen;
 299                 while (len > 0 && isspace(*ptr)) {
 300                         ptr++;
 301                         len--;
 302                 }
 303
 304                 if (match_word(word, wordlen, "reset")) {
 305                         has_reset = 1;
 306                         continue;
 307                 }
 308
 309                 if (!parse_color(&c, word, wordlen)) {
 310                         if (fg.type == COLOR_UNSPECIFIED) {
 311                                 fg = c;
 312                                 continue;
 313                         }
 314                         if (bg.type == COLOR_UNSPECIFIED) {
 315                                 bg = c;
 316                                 continue;
 317                         }
 318                         goto bad;
 319                 }
 320                 val = parse_attr(word, wordlen);
 321                 if (0 <= val)
 322                         attr |= (1 << val);
 323                 else
 324                         goto bad;
 325         }
 326
 327 #undef OUT
 328 #define OUT(x) do { \
 329         if (dst == end) \
 330                 BUG("color parsing ran out of space"); \
 331         *dst++ = (x); \
 332 } while(0)
 333
 334         if (has_reset || attr || !color_empty(&fg) || !color_empty(&bg)) {
 335                 int sep = 0;
 336                 int i;
 337
 338                 OUT('\033');
 339                 OUT('[');
 340
 341                 if (has_reset)
 342                         sep++;
 343
 344                 for (i = 0; attr; i++) {
 345                         unsigned bit = (1 << i);
 346                         if (!(attr & bit))
 347                                 continue;
 348                         attr &= ~bit;
 349                         if (sep++)
 350                                 OUT(';');
 351                         dst += xsnprintf(dst, end - dst, "%d", i);
 352                 }
 353                 if (!color_empty(&fg)) {
 354                         if (sep++)
 355                                 OUT(';');
 356                         dst = color_output(dst, end - dst, &fg, 0);
 357                 }
 358                 if (!color_empty(&bg)) {
 359                         if (sep++)
 360                                 OUT(';');
 361                         dst = color_output(dst, end - dst, &bg, 1);
 362                 }
 363                 OUT('m');
 364         }
 365         OUT(0);
 366         return 0;
 367 bad:
 368         return error(_("invalid color value: %.*s"), value_len, value);
 369 #undef OUT
 370 }
 371
 372 int git_config_colorbool(const char *var, const char *value)
 373 {
 374         if (value) {
 375                 if (!strcasecmp(value, "never"))
 376                         return 0;
 377                 if (!strcasecmp(value, "always"))
 378                         return 1;
 379                 if (!strcasecmp(value, "auto"))
 380                         return GIT_COLOR_AUTO;
 381         }
 382
 383         if (!var)
 384                 return -1;
 385
 386         /* Missing or explicit false to turn off colorization */
 387         if (!git_config_bool(var, value))
 388                 return 0;
 389
 390         /* any normal truth value defaults to 'auto' */
 391         return GIT_COLOR_AUTO;
 392 }
 393
 394 static int check_auto_color(int fd)
 395 {
 396         static int color_stderr_is_tty = -1;
 397         int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
 398         if (*is_tty_p < 0)
 399                 *is_tty_p = isatty(fd);
 400         if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
 401                 if (!is_terminal_dumb())
 402                         return 1;
 403         }
 404         return 0;
 405 }
 406
 407 int want_color_fd(int fd, int var)
 408 {
 409         /*
 410          * NEEDSWORK: This function is sometimes used from multiple threads, and
 411          * we end up using want_auto racily. That "should not matter" since
 412          * we always write the same value, but it's still wrong. This function
 413          * is listed in .tsan-suppressions for the time being.
 414          */
 415
 416         static int want_auto[3] = { -1, -1, -1 };
 417
 418         if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
 419                 BUG("file descriptor out of range: %d", fd);
 420
 421         if (var < 0)
 422                 var = git_use_color_default;
 423
 424         if (var == GIT_COLOR_AUTO) {
 425                 if (want_auto[fd] < 0)
 426                         want_auto[fd] = check_auto_color(fd);
 427                 return want_auto[fd];
 428         }
 429         return var;
 430 }
 431
 432 int git_color_config(const char *var, const char *value, void *cb UNUSED)
 433 {
 434         if (!strcmp(var, "color.ui")) {
 435                 git_use_color_default = git_config_colorbool(var, value);
 436                 return 0;
 437         }
 438
 439         return 0;
 440 }
 441
 442 void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
 443 {
 444         if (*color)
 445                 fprintf(fp, "%s", color);
 446         fprintf(fp, "%s", sb->buf);
 447         if (*color)
 448                 fprintf(fp, "%s", GIT_COLOR_RESET);
 449 }
 450
 451 static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
 452                 va_list args, const char *trail)
 453 {
 454         int r = 0;
 455
 456         if (*color)
 457                 r += fprintf(fp, "%s", color);
 458         r += vfprintf(fp, fmt, args);
 459         if (*color)
 460                 r += fprintf(fp, "%s", GIT_COLOR_RESET);
 461         if (trail)
 462                 r += fprintf(fp, "%s", trail);
 463         return r;
 464 }
 465
 466 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
 467 {
 468         va_list args;
 469         int r;
 470         va_start(args, fmt);
 471         r = color_vfprintf(fp, color, fmt, args, NULL);
 472         va_end(args);
 473         return r;
 474 }
 475
 476 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 477 {
 478         va_list args;
 479         int r;
 480         va_start(args, fmt);
 481         r = color_vfprintf(fp, color, fmt, args, "\n");
 482         va_end(args);
 483         return r;
 484 }
 485
 486 int color_is_nil(const char *c)
 487 {
 488         return !strcmp(c, "NIL");
 489 }