color.con commit t/lib-diff-alternative: abstract away SHA-1-specific constants (d29d500)
   1#include "cache.h"
   2#include "config.h"
   3#include "color.h"
   4
   5static int git_use_color_default = GIT_COLOR_AUTO;
   6int color_stdout_is_tty = -1;
   7
   8/*
   9 * The list of available column colors.
  10 */
  11const 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/* Ignore the RESET at the end when giving the size */
  28const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
  29
  30/* An individual foreground or background color. */
  31struct color {
  32        enum {
  33                COLOR_UNSPECIFIED = 0,
  34                COLOR_NORMAL,
  35                COLOR_ANSI, /* basic 0-7 ANSI colors */
  36                COLOR_256,
  37                COLOR_RGB
  38        } type;
  39        /* The numeric value for ANSI and 256-color modes */
  40        unsigned char value;
  41        /* 24-bit RGB color values */
  42        unsigned char red, green, blue;
  43};
  44
  45/*
  46 * "word" is a buffer of length "len"; does it match the NUL-terminated
  47 * "match" exactly?
  48 */
  49static int match_word(const char *word, int len, const char *match)
  50{
  51        return !strncasecmp(word, match, len) && !match[len];
  52}
  53
  54static int get_hex_color(const char *in, unsigned char *out)
  55{
  56        unsigned int val;
  57        val = (hexval(in[0]) << 4) | hexval(in[1]);
  58        if (val & ~0xff)
  59                return -1;
  60        *out = val;
  61        return 0;
  62}
  63
  64static int parse_color(struct color *out, const char *name, int len)
  65{
  66        /* Positions in array must match ANSI color codes */
  67        static const char * const color_names[] = {
  68                "black", "red", "green", "yellow",
  69                "blue", "magenta", "cyan", "white"
  70        };
  71        char *end;
  72        int i;
  73        long val;
  74
  75        /* First try the special word "normal"... */
  76        if (match_word(name, len, "normal")) {
  77                out->type = COLOR_NORMAL;
  78                return 0;
  79        }
  80
  81        /* Try a 24-bit RGB value */
  82        if (len == 7 && name[0] == '#') {
  83                if (!get_hex_color(name + 1, &out->red) &&
  84                    !get_hex_color(name + 3, &out->green) &&
  85                    !get_hex_color(name + 5, &out->blue)) {
  86                        out->type = COLOR_RGB;
  87                        return 0;
  88                }
  89        }
  90
  91        /* Then pick from our human-readable color names... */
  92        for (i = 0; i < ARRAY_SIZE(color_names); i++) {
  93                if (match_word(name, len, color_names[i])) {
  94                        out->type = COLOR_ANSI;
  95                        out->value = i;
  96                        return 0;
  97                }
  98        }
  99
 100        /* And finally try a literal 256-color-mode number */
 101        val = strtol(name, &end, 10);
 102        if (end - name == len) {
 103                /*
 104                 * Allow "-1" as an alias for "normal", but other negative
 105                 * numbers are bogus.
 106                 */
 107                if (val < -1)
 108                        ; /* fall through to error */
 109                else if (val < 0) {
 110                        out->type = COLOR_NORMAL;
 111                        return 0;
 112                /* Rewrite low numbers as more-portable standard colors. */
 113                } else if (val < 8) {
 114                        out->type = COLOR_ANSI;
 115                        out->value = val;
 116                        return 0;
 117                } else if (val < 256) {
 118                        out->type = COLOR_256;
 119                        out->value = val;
 120                        return 0;
 121                }
 122        }
 123
 124        return -1;
 125}
 126
 127static int parse_attr(const char *name, size_t len)
 128{
 129        static const struct {
 130                const char *name;
 131                size_t len;
 132                int val, neg;
 133        } attrs[] = {
 134#define ATTR(x, val, neg) { (x), sizeof(x)-1, (val), (neg) }
 135                ATTR("bold",      1, 22),
 136                ATTR("dim",       2, 22),
 137                ATTR("italic",    3, 23),
 138                ATTR("ul",        4, 24),
 139                ATTR("blink",     5, 25),
 140                ATTR("reverse",   7, 27),
 141                ATTR("strike",    9, 29)
 142#undef ATTR
 143        };
 144        int negate = 0;
 145        int i;
 146
 147        if (skip_prefix_mem(name, len, "no", &name, &len)) {
 148                skip_prefix_mem(name, len, "-", &name, &len);
 149                negate = 1;
 150        }
 151
 152        for (i = 0; i < ARRAY_SIZE(attrs); i++) {
 153                if (attrs[i].len == len && !memcmp(attrs[i].name, name, len))
 154                        return negate ? attrs[i].neg : attrs[i].val;
 155        }
 156        return -1;
 157}
 158
 159int color_parse(const char *value, char *dst)
 160{
 161        return color_parse_mem(value, strlen(value), dst);
 162}
 163
 164/*
 165 * Write the ANSI color codes for "c" to "out"; the string should
 166 * already have the ANSI escape code in it. "out" should have enough
 167 * space in it to fit any color.
 168 */
 169static char *color_output(char *out, int len, const struct color *c, char type)
 170{
 171        switch (c->type) {
 172        case COLOR_UNSPECIFIED:
 173        case COLOR_NORMAL:
 174                break;
 175        case COLOR_ANSI:
 176                if (len < 2)
 177                        die("BUG: color parsing ran out of space");
 178                *out++ = type;
 179                *out++ = '0' + c->value;
 180                break;
 181        case COLOR_256:
 182                out += xsnprintf(out, len, "%c8;5;%d", type, c->value);
 183                break;
 184        case COLOR_RGB:
 185                out += xsnprintf(out, len, "%c8;2;%d;%d;%d", type,
 186                                 c->red, c->green, c->blue);
 187                break;
 188        }
 189        return out;
 190}
 191
 192static int color_empty(const struct color *c)
 193{
 194        return c->type <= COLOR_NORMAL;
 195}
 196
 197int color_parse_mem(const char *value, int value_len, char *dst)
 198{
 199        const char *ptr = value;
 200        int len = value_len;
 201        char *end = dst + COLOR_MAXLEN;
 202        unsigned int attr = 0;
 203        struct color fg = { COLOR_UNSPECIFIED };
 204        struct color bg = { COLOR_UNSPECIFIED };
 205
 206        while (len > 0 && isspace(*ptr)) {
 207                ptr++;
 208                len--;
 209        }
 210
 211        if (!len) {
 212                dst[0] = '\0';
 213                return 0;
 214        }
 215
 216        if (!strncasecmp(ptr, "reset", len)) {
 217                xsnprintf(dst, end - dst, GIT_COLOR_RESET);
 218                return 0;
 219        }
 220
 221        /* [fg [bg]] [attr]... */
 222        while (len > 0) {
 223                const char *word = ptr;
 224                struct color c = { COLOR_UNSPECIFIED };
 225                int val, wordlen = 0;
 226
 227                while (len > 0 && !isspace(word[wordlen])) {
 228                        wordlen++;
 229                        len--;
 230                }
 231
 232                ptr = word + wordlen;
 233                while (len > 0 && isspace(*ptr)) {
 234                        ptr++;
 235                        len--;
 236                }
 237
 238                if (!parse_color(&c, word, wordlen)) {
 239                        if (fg.type == COLOR_UNSPECIFIED) {
 240                                fg = c;
 241                                continue;
 242                        }
 243                        if (bg.type == COLOR_UNSPECIFIED) {
 244                                bg = c;
 245                                continue;
 246                        }
 247                        goto bad;
 248                }
 249                val = parse_attr(word, wordlen);
 250                if (0 <= val)
 251                        attr |= (1 << val);
 252                else
 253                        goto bad;
 254        }
 255
 256#undef OUT
 257#define OUT(x) do { \
 258        if (dst == end) \
 259                die("BUG: color parsing ran out of space"); \
 260        *dst++ = (x); \
 261} while(0)
 262
 263        if (attr || !color_empty(&fg) || !color_empty(&bg)) {
 264                int sep = 0;
 265                int i;
 266
 267                OUT('\033');
 268                OUT('[');
 269
 270                for (i = 0; attr; i++) {
 271                        unsigned bit = (1 << i);
 272                        if (!(attr & bit))
 273                                continue;
 274                        attr &= ~bit;
 275                        if (sep++)
 276                                OUT(';');
 277                        dst += xsnprintf(dst, end - dst, "%d", i);
 278                }
 279                if (!color_empty(&fg)) {
 280                        if (sep++)
 281                                OUT(';');
 282                        /* foreground colors are all in the 3x range */
 283                        dst = color_output(dst, end - dst, &fg, '3');
 284                }
 285                if (!color_empty(&bg)) {
 286                        if (sep++)
 287                                OUT(';');
 288                        /* background colors are all in the 4x range */
 289                        dst = color_output(dst, end - dst, &bg, '4');
 290                }
 291                OUT('m');
 292        }
 293        OUT(0);
 294        return 0;
 295bad:
 296        return error(_("invalid color value: %.*s"), value_len, value);
 297#undef OUT
 298}
 299
 300int git_config_colorbool(const char *var, const char *value)
 301{
 302        if (value) {
 303                if (!strcasecmp(value, "never"))
 304                        return 0;
 305                if (!strcasecmp(value, "always"))
 306                        return 1;
 307                if (!strcasecmp(value, "auto"))
 308                        return GIT_COLOR_AUTO;
 309        }
 310
 311        if (!var)
 312                return -1;
 313
 314        /* Missing or explicit false to turn off colorization */
 315        if (!git_config_bool(var, value))
 316                return 0;
 317
 318        /* any normal truth value defaults to 'auto' */
 319        return GIT_COLOR_AUTO;
 320}
 321
 322static int check_auto_color(int fd)
 323{
 324        static int color_stderr_is_tty = -1;
 325        int *is_tty_p = fd == 1 ? &color_stdout_is_tty : &color_stderr_is_tty;
 326        if (*is_tty_p < 0)
 327                *is_tty_p = isatty(fd);
 328        if (*is_tty_p || (fd == 1 && pager_in_use() && pager_use_color)) {
 329                if (!is_terminal_dumb())
 330                        return 1;
 331        }
 332        return 0;
 333}
 334
 335int want_color_fd(int fd, int var)
 336{
 337        /*
 338         * NEEDSWORK: This function is sometimes used from multiple threads, and
 339         * we end up using want_auto racily. That "should not matter" since
 340         * we always write the same value, but it's still wrong. This function
 341         * is listed in .tsan-suppressions for the time being.
 342         */
 343
 344        static int want_auto[3] = { -1, -1, -1 };
 345
 346        if (var < 0)
 347                var = git_use_color_default;
 348
 349        if (var == GIT_COLOR_AUTO) {
 350                if (want_auto[fd] < 0)
 351                        want_auto[fd] = check_auto_color(fd);
 352                return want_auto[fd];
 353        }
 354        return var;
 355}
 356
 357int git_color_config(const char *var, const char *value, void *cb)
 358{
 359        if (!strcmp(var, "color.ui")) {
 360                git_use_color_default = git_config_colorbool(var, value);
 361                return 0;
 362        }
 363
 364        return 0;
 365}
 366
 367int git_color_default_config(const char *var, const char *value, void *cb)
 368{
 369        if (git_color_config(var, value, cb) < 0)
 370                return -1;
 371
 372        return git_default_config(var, value, cb);
 373}
 374
 375void color_print_strbuf(FILE *fp, const char *color, const struct strbuf *sb)
 376{
 377        if (*color)
 378                fprintf(fp, "%s", color);
 379        fprintf(fp, "%s", sb->buf);
 380        if (*color)
 381                fprintf(fp, "%s", GIT_COLOR_RESET);
 382}
 383
 384static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
 385                va_list args, const char *trail)
 386{
 387        int r = 0;
 388
 389        if (*color)
 390                r += fprintf(fp, "%s", color);
 391        r += vfprintf(fp, fmt, args);
 392        if (*color)
 393                r += fprintf(fp, "%s", GIT_COLOR_RESET);
 394        if (trail)
 395                r += fprintf(fp, "%s", trail);
 396        return r;
 397}
 398
 399int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
 400{
 401        va_list args;
 402        int r;
 403        va_start(args, fmt);
 404        r = color_vfprintf(fp, color, fmt, args, NULL);
 405        va_end(args);
 406        return r;
 407}
 408
 409int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 410{
 411        va_list args;
 412        int r;
 413        va_start(args, fmt);
 414        r = color_vfprintf(fp, color, fmt, args, "\n");
 415        va_end(args);
 416        return r;
 417}
 418
 419int color_is_nil(const char *c)
 420{
 421        return !strcmp(c, "NIL");
 422}