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