src/dircolors.c

   1 /* dircolors - output commands to set the LS_COLOR environment variable
   2    Copyright (C) 1996-2022 Free Software Foundation, Inc.
   3    Copyright (C) 1994, 1995, 1997, 1998, 1999, 2000 H. Peter Anvin
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation, either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 #include <sys/types.h>
  21 #include <fnmatch.h>
  22 #include <getopt.h>
  23
  24 #include "system.h"
  25 #include "dircolors.h"
  26 #include "c-strcase.h"
  27 #include "die.h"
  28 #include "error.h"
  29 #include "obstack.h"
  30 #include "quote.h"
  31 #include "stdio--.h"
  32
  33 /* The official name of this program (e.g., no 'g' prefix).  */
  34 #define PROGRAM_NAME "dircolors"
  35
  36 #define AUTHORS proper_name ("H. Peter Anvin")
  37
  38 #define obstack_chunk_alloc malloc
  39 #define obstack_chunk_free free
  40
  41 enum Shell_syntax
  42 {
  43   SHELL_SYNTAX_BOURNE,
  44   SHELL_SYNTAX_C,
  45   SHELL_SYNTAX_UNKNOWN
  46 };
  47
  48 #define APPEND_CHAR(C) obstack_1grow (&lsc_obstack, C)
  49 #define APPEND_TWO_CHAR_STRING(S)                                       \
  50   do                                                                    \
  51     {                                                                   \
  52       APPEND_CHAR (S[0]);                                               \
  53       APPEND_CHAR (S[1]);                                               \
  54     }                                                                   \
  55   while (0)
  56
  57 /* Accumulate in this obstack the value for the LS_COLORS environment
  58    variable.  */
  59 static struct obstack lsc_obstack;
  60
  61 static char const *const slack_codes[] =
  62 {
  63   "NORMAL", "NORM", "FILE", "RESET", "DIR", "LNK", "LINK",
  64   "SYMLINK", "ORPHAN", "MISSING", "FIFO", "PIPE", "SOCK", "BLK", "BLOCK",
  65   "CHR", "CHAR", "DOOR", "EXEC", "LEFT", "LEFTCODE", "RIGHT", "RIGHTCODE",
  66   "END", "ENDCODE", "SUID", "SETUID", "SGID", "SETGID", "STICKY",
  67   "OTHER_WRITABLE", "OWR", "STICKY_OTHER_WRITABLE", "OWT", "CAPABILITY",
  68   "MULTIHARDLINK", "CLRTOEOL", NULL
  69 };
  70
  71 static char const *const ls_codes[] =
  72 {
  73   "no", "no", "fi", "rs", "di", "ln", "ln", "ln", "or", "mi", "pi", "pi",
  74   "so", "bd", "bd", "cd", "cd", "do", "ex", "lc", "lc", "rc", "rc", "ec", "ec",
  75   "su", "su", "sg", "sg", "st", "ow", "ow", "tw", "tw", "ca", "mh", "cl", NULL
  76 };
  77 verify (ARRAY_CARDINALITY (slack_codes) == ARRAY_CARDINALITY (ls_codes));
  78
  79 static struct option const long_options[] =
  80   {
  81     {"bourne-shell", no_argument, NULL, 'b'},
  82     {"sh", no_argument, NULL, 'b'},
  83     {"csh", no_argument, NULL, 'c'},
  84     {"c-shell", no_argument, NULL, 'c'},
  85     {"print-database", no_argument, NULL, 'p'},
  86     {GETOPT_HELP_OPTION_DECL},
  87     {GETOPT_VERSION_OPTION_DECL},
  88     {NULL, 0, NULL, 0}
  89   };
  90
  91 void
  92 usage (int status)
  93 {
  94   if (status != EXIT_SUCCESS)
  95     emit_try_help ();
  96   else
  97     {
  98       printf (_("Usage: %s [OPTION]... [FILE]\n"), program_name);
  99       fputs (_("\
 100 Output commands to set the LS_COLORS environment variable.\n\
 101 \n\
 102 Determine format of output:\n\
 103   -b, --sh, --bourne-shell    output Bourne shell code to set LS_COLORS\n\
 104   -c, --csh, --c-shell        output C shell code to set LS_COLORS\n\
 105   -p, --print-database        output defaults\n\
 106 "), stdout);
 107       fputs (HELP_OPTION_DESCRIPTION, stdout);
 108       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 109       fputs (_("\
 110 \n\
 111 If FILE is specified, read it to determine which colors to use for which\n\
 112 file types and extensions.  Otherwise, a precompiled database is used.\n\
 113 For details on the format of these files, run 'dircolors --print-database'.\n\
 114 "), stdout);
 115       emit_ancillary_info (PROGRAM_NAME);
 116     }
 117
 118   exit (status);
 119 }
 120
 121 /* If the SHELL environment variable is set to 'csh' or 'tcsh,'
 122    assume C shell.  Else Bourne shell.  */
 123
 124 static enum Shell_syntax
 125 guess_shell_syntax (void)
 126 {
 127   char *shell;
 128
 129   shell = getenv ("SHELL");
 130   if (shell == NULL || *shell == '\0')
 131     return SHELL_SYNTAX_UNKNOWN;
 132
 133   shell = last_component (shell);
 134
 135   if (STREQ (shell, "csh") || STREQ (shell, "tcsh"))
 136     return SHELL_SYNTAX_C;
 137
 138   return SHELL_SYNTAX_BOURNE;
 139 }
 140
 141 static void
 142 parse_line (char const *line, char **keyword, char **arg)
 143 {
 144   char const *p;
 145   char const *keyword_start;
 146   char const *arg_start;
 147
 148   *keyword = NULL;
 149   *arg = NULL;
 150
 151   for (p = line; isspace (to_uchar (*p)); ++p)
 152     continue;
 153
 154   /* Ignore blank lines and shell-style comments.  */
 155   if (*p == '\0' || *p == '#')
 156     return;
 157
 158   keyword_start = p;
 159
 160   while (!isspace (to_uchar (*p)) && *p != '\0')
 161     {
 162       ++p;
 163     }
 164
 165   *keyword = ximemdup0 (keyword_start, p - keyword_start);
 166   if (*p  == '\0')
 167     return;
 168
 169   do
 170     {
 171       ++p;
 172     }
 173   while (isspace (to_uchar (*p)));
 174
 175   if (*p == '\0' || *p == '#')
 176     return;
 177
 178   arg_start = p;
 179
 180   while (*p != '\0' && *p != '#')
 181     ++p;
 182
 183   for (--p; isspace (to_uchar (*p)); --p)
 184     continue;
 185   ++p;
 186
 187   *arg = ximemdup0 (arg_start, p - arg_start);
 188 }
 189
 190 /* FIXME: Write a string to standard out, while watching for "dangerous"
 191    sequences like unescaped : and = characters.  */
 192
 193 static void
 194 append_quoted (char const *str)
 195 {
 196   bool need_backslash = true;
 197
 198   while (*str != '\0')
 199     {
 200       switch (*str)
 201         {
 202         case '\'':
 203           APPEND_CHAR ('\'');
 204           APPEND_CHAR ('\\');
 205           APPEND_CHAR ('\'');
 206           need_backslash = true;
 207           break;
 208
 209         case '\\':
 210         case '^':
 211           need_backslash = !need_backslash;
 212           break;
 213
 214         case ':':
 215         case '=':
 216           if (need_backslash)
 217             APPEND_CHAR ('\\');
 218           FALLTHROUGH;
 219
 220         default:
 221           need_backslash = true;
 222           break;
 223         }
 224
 225       APPEND_CHAR (*str);
 226       ++str;
 227     }
 228 }
 229
 230 /* Read the file open on FP (with name FILENAME).  First, look for a
 231    'TERM name' directive where name matches the current terminal type.
 232    Once found, translate and accumulate the associated directives onto
 233    the global obstack LSC_OBSTACK.  Give a diagnostic
 234    upon failure (unrecognized keyword is the only way to fail here).
 235    Return true if successful.  */
 236
 237 static bool
 238 dc_parse_stream (FILE *fp, char const *filename)
 239 {
 240   size_t line_number = 0;
 241   char const *next_G_line = G_line;
 242   char *input_line = NULL;
 243   size_t input_line_size = 0;
 244   char const *line;
 245   char const *term;
 246   bool ok = true;
 247
 248   /* State for the parser.  */
 249   enum { ST_TERMNO, ST_TERMYES, ST_TERMSURE, ST_GLOBAL } state = ST_GLOBAL;
 250
 251   /* Get terminal type */
 252   term = getenv ("TERM");
 253   if (term == NULL || *term == '\0')
 254     term = "none";
 255
 256   while (true)
 257     {
 258       char *keywd, *arg;
 259       bool unrecognized;
 260
 261       ++line_number;
 262
 263       if (fp)
 264         {
 265           if (getline (&input_line, &input_line_size, fp) <= 0)
 266             {
 267               free (input_line);
 268               break;
 269             }
 270           line = input_line;
 271         }
 272       else
 273         {
 274           if (next_G_line == G_line + sizeof G_line)
 275             break;
 276           line = next_G_line;
 277           next_G_line += strlen (next_G_line) + 1;
 278         }
 279
 280       parse_line (line, &keywd, &arg);
 281
 282       if (keywd == NULL)
 283         continue;
 284
 285       if (arg == NULL)
 286         {
 287           error (0, 0, _("%s:%lu: invalid line;  missing second token"),
 288                  quotef (filename), (unsigned long int) line_number);
 289           ok = false;
 290           free (keywd);
 291           continue;
 292         }
 293
 294       unrecognized = false;
 295       if (c_strcasecmp (keywd, "TERM") == 0)
 296         {
 297           if (fnmatch (arg, term, 0) == 0)
 298             state = ST_TERMSURE;
 299           else if (state != ST_TERMSURE)
 300             state = ST_TERMNO;
 301         }
 302       else
 303         {
 304           if (state == ST_TERMSURE)
 305             state = ST_TERMYES; /* Another TERM can cancel */
 306
 307           if (state != ST_TERMNO)
 308             {
 309               if (keywd[0] == '.')
 310                 {
 311                   APPEND_CHAR ('*');
 312                   append_quoted (keywd);
 313                   APPEND_CHAR ('=');
 314                   append_quoted (arg);
 315                   APPEND_CHAR (':');
 316                 }
 317               else if (keywd[0] == '*')
 318                 {
 319                   append_quoted (keywd);
 320                   APPEND_CHAR ('=');
 321                   append_quoted (arg);
 322                   APPEND_CHAR (':');
 323                 }
 324               else if (c_strcasecmp (keywd, "OPTIONS") == 0
 325                        || c_strcasecmp (keywd, "COLOR") == 0
 326                        || c_strcasecmp (keywd, "EIGHTBIT") == 0)
 327                 {
 328                   /* Ignore.  */
 329                 }
 330               else
 331                 {
 332                   int i;
 333
 334                   for (i = 0; slack_codes[i] != NULL; ++i)
 335                     if (c_strcasecmp (keywd, slack_codes[i]) == 0)
 336                       break;
 337
 338                   if (slack_codes[i] != NULL)
 339                     {
 340                       APPEND_TWO_CHAR_STRING (ls_codes[i]);
 341                       APPEND_CHAR ('=');
 342                       append_quoted (arg);
 343                       APPEND_CHAR (':');
 344                     }
 345                   else
 346                     {
 347                       unrecognized = true;
 348                     }
 349                 }
 350             }
 351           else
 352             {
 353               unrecognized = true;
 354             }
 355         }
 356
 357       if (unrecognized && (state == ST_TERMSURE || state == ST_TERMYES))
 358         {
 359           error (0, 0, _("%s:%lu: unrecognized keyword %s"),
 360                  (filename ? quotef (filename) : _("<internal>")),
 361                  (unsigned long int) line_number, keywd);
 362           ok = false;
 363         }
 364
 365       free (keywd);
 366       free (arg);
 367     }
 368
 369   return ok;
 370 }
 371
 372 static bool
 373 dc_parse_file (char const *filename)
 374 {
 375   bool ok;
 376
 377   if (! STREQ (filename, "-") && freopen (filename, "r", stdin) == NULL)
 378     {
 379       error (0, errno, "%s", quotef (filename));
 380       return false;
 381     }
 382
 383   ok = dc_parse_stream (stdin, filename);
 384
 385   if (fclose (stdin) != 0)
 386     {
 387       error (0, errno, "%s", quotef (filename));
 388       return false;
 389     }
 390
 391   return ok;
 392 }
 393
 394 int
 395 main (int argc, char **argv)
 396 {
 397   bool ok = true;
 398   int optc;
 399   enum Shell_syntax syntax = SHELL_SYNTAX_UNKNOWN;
 400   bool print_database = false;
 401
 402   initialize_main (&argc, &argv);
 403   set_program_name (argv[0]);
 404   setlocale (LC_ALL, "");
 405   bindtextdomain (PACKAGE, LOCALEDIR);
 406   textdomain (PACKAGE);
 407
 408   atexit (close_stdout);
 409
 410   while ((optc = getopt_long (argc, argv, "bcp", long_options, NULL)) != -1)
 411     switch (optc)
 412       {
 413       case 'b': /* Bourne shell syntax.  */
 414         syntax = SHELL_SYNTAX_BOURNE;
 415         break;
 416
 417       case 'c': /* C shell syntax.  */
 418         syntax = SHELL_SYNTAX_C;
 419         break;
 420
 421       case 'p':
 422         print_database = true;
 423         break;
 424
 425       case_GETOPT_HELP_CHAR;
 426
 427       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 428
 429       default:
 430         usage (EXIT_FAILURE);
 431       }
 432
 433   argc -= optind;
 434   argv += optind;
 435
 436   /* It doesn't make sense to use --print with either of
 437      --bourne or --c-shell.  */
 438   if (print_database && syntax != SHELL_SYNTAX_UNKNOWN)
 439     {
 440       error (0, 0,
 441              _("the options to output dircolors' internal database and\n"
 442                "to select a shell syntax are mutually exclusive"));
 443       usage (EXIT_FAILURE);
 444     }
 445
 446   if ((!print_database) < argc)
 447     {
 448       error (0, 0, _("extra operand %s"), quote (argv[!print_database]));
 449       if (print_database)
 450         fprintf (stderr, "%s\n",
 451                  _("file operands cannot be combined with "
 452                    "--print-database (-p)"));
 453       usage (EXIT_FAILURE);
 454     }
 455
 456   if (print_database)
 457     {
 458       char const *p = G_line;
 459       while (p - G_line < sizeof G_line)
 460         {
 461           puts (p);
 462           p += strlen (p) + 1;
 463         }
 464     }
 465   else
 466     {
 467       /* If shell syntax was not explicitly specified, try to guess it. */
 468       if (syntax == SHELL_SYNTAX_UNKNOWN)
 469         {
 470           syntax = guess_shell_syntax ();
 471           if (syntax == SHELL_SYNTAX_UNKNOWN)
 472             {
 473               die (EXIT_FAILURE, 0,
 474          _("no SHELL environment variable, and no shell type option given"));
 475             }
 476         }
 477
 478       obstack_init (&lsc_obstack);
 479       if (argc == 0)
 480         ok = dc_parse_stream (NULL, NULL);
 481       else
 482         ok = dc_parse_file (argv[0]);
 483
 484       if (ok)
 485         {
 486           size_t len = obstack_object_size (&lsc_obstack);
 487           char *s = obstack_finish (&lsc_obstack);
 488           char const *prefix;
 489           char const *suffix;
 490
 491           if (syntax == SHELL_SYNTAX_BOURNE)
 492             {
 493               prefix = "LS_COLORS='";
 494               suffix = "';\nexport LS_COLORS\n";
 495             }
 496           else
 497             {
 498               prefix = "setenv LS_COLORS '";
 499               suffix = "'\n";
 500             }
 501           fputs (prefix, stdout);
 502           fwrite (s, 1, len, stdout);
 503           fputs (suffix, stdout);
 504         }
 505     }
 506
 507   return ok ? EXIT_SUCCESS : EXIT_FAILURE;
 508 }