test.c

   1 /* GNU test program (ksb and mjb) */
   2
   3 /* Modified to run with the GNU shell Apr 25, 1988 by bfox. */
   4
   5 /* Copyright (C) 1987-2005 Free Software Foundation, Inc.
   6
   7    This file is part of GNU Bash, the Bourne Again SHell.
   8
   9    Bash is free software; you can redistribute it and/or modify it under
  10    the terms of the GNU General Public License as published by the Free
  11    Software Foundation; either version 2, or (at your option) any later
  12    version.
  13
  14    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  15    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17    for more details.
  18
  19    You should have received a copy of the GNU General Public License along
  20    with Bash; see the file COPYING.  If not, write to the Free Software
  21    Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  22
  23 /* Define PATTERN_MATCHING to get the csh-like =~ and !~ pattern-matching
  24    binary operators. */
  25 /* #define PATTERN_MATCHING */
  26
  27 #if defined (HAVE_CONFIG_H)
  28 #  include <config.h>
  29 #endif
  30
  31 #include <stdio.h>
  32
  33 #include "bashtypes.h"
  34
  35 #if !defined (HAVE_LIMITS_H)
  36 #  include <sys/param.h>
  37 #endif
  38
  39 #if defined (HAVE_UNISTD_H)
  40 #  include <unistd.h>
  41 #endif
  42
  43 #include <errno.h>
  44 #if !defined (errno)
  45 extern int errno;
  46 #endif /* !errno */
  47
  48 #if !defined (_POSIX_VERSION) && defined (HAVE_SYS_FILE_H)
  49 #  include <sys/file.h>
  50 #endif /* !_POSIX_VERSION */
  51 #include "posixstat.h"
  52 #include "filecntl.h"
  53
  54 #include "bashintl.h"
  55
  56 #include "shell.h"
  57 #include "pathexp.h"
  58 #include "test.h"
  59 #include "builtins/common.h"
  60
  61 #include <glob/strmatch.h>
  62
  63 #if !defined (STRLEN)
  64 #  define STRLEN(s) ((s)[0] ? ((s)[1] ? ((s)[2] ? strlen(s) : 2) : 1) : 0)
  65 #endif
  66
  67 #if !defined (STREQ)
  68 #  define STREQ(a, b) ((a)[0] == (b)[0] && strcmp (a, b) == 0)
  69 #endif /* !STREQ */
  70
  71 #if !defined (R_OK)
  72 #define R_OK 4
  73 #define W_OK 2
  74 #define X_OK 1
  75 #define F_OK 0
  76 #endif /* R_OK */
  77
  78 #define EQ      0
  79 #define NE      1
  80 #define LT      2
  81 #define GT      3
  82 #define LE      4
  83 #define GE      5
  84
  85 #define NT      0
  86 #define OT      1
  87 #define EF      2
  88
  89 /* The following few defines control the truth and false output of each stage.
  90    TRUE and FALSE are what we use to compute the final output value.
  91    SHELL_BOOLEAN is the form which returns truth or falseness in shell terms.
  92    Default is TRUE = 1, FALSE = 0, SHELL_BOOLEAN = (!value). */
  93 #define TRUE 1
  94 #define FALSE 0
  95 #define SHELL_BOOLEAN(value) (!(value))
  96
  97 #define TEST_ERREXIT_STATUS     2
  98
  99 static procenv_t test_exit_buf;
 100 static int test_error_return;
 101 #define test_exit(val) \
 102         do { test_error_return = val; longjmp (test_exit_buf, 1); } while (0)
 103
 104 extern int sh_stat __P((const char *, struct stat *));
 105
 106 static int pos;         /* The offset of the current argument in ARGV. */
 107 static int argc;        /* The number of arguments present in ARGV. */
 108 static char **argv;     /* The argument list. */
 109 static int noeval;
 110
 111 static void test_syntax_error __P((char *, char *)) __attribute__((__noreturn__));
 112 static void beyond __P((void)) __attribute__((__noreturn__));
 113 static void integer_expected_error __P((char *)) __attribute__((__noreturn__));
 114
 115 static int unary_operator __P((void));
 116 static int binary_operator __P((void));
 117 static int two_arguments __P((void));
 118 static int three_arguments __P((void));
 119 static int posixtest __P((void));
 120
 121 static int expr __P((void));
 122 static int term __P((void));
 123 static int and __P((void));
 124 static int or __P((void));
 125
 126 static int filecomp __P((char *, char *, int));
 127 static int arithcomp __P((char *, char *, int, int));
 128 static int patcomp __P((char *, char *, int));
 129
 130 static void
 131 test_syntax_error (format, arg)
 132      char *format, *arg;
 133 {
 134   builtin_error (format, arg);
 135   test_exit (TEST_ERREXIT_STATUS);
 136 }
 137
 138 /*
 139  * beyond - call when we're beyond the end of the argument list (an
 140  *      error condition)
 141  */
 142 static void
 143 beyond ()
 144 {
 145   test_syntax_error (_("argument expected"), (char *)NULL);
 146 }
 147
 148 /* Syntax error for when an integer argument was expected, but
 149    something else was found. */
 150 static void
 151 integer_expected_error (pch)
 152      char *pch;
 153 {
 154   test_syntax_error (_("%s: integer expression expected"), pch);
 155 }
 156
 157 /* Increment our position in the argument list.  Check that we're not
 158    past the end of the argument list.  This check is supressed if the
 159    argument is FALSE.  Made a macro for efficiency. */
 160 #define advance(f) do { ++pos; if (f && pos >= argc) beyond (); } while (0)
 161 #define unary_advance() do { advance (1); ++pos; } while (0)
 162
 163 /*
 164  * expr:
 165  *      or
 166  */
 167 static int
 168 expr ()
 169 {
 170   if (pos >= argc)
 171     beyond ();
 172
 173   return (FALSE ^ or ());               /* Same with this. */
 174 }
 175
 176 /*
 177  * or:
 178  *      and
 179  *      and '-o' or
 180  */
 181 static int
 182 or ()
 183 {
 184   int value, v2;
 185
 186   value = and ();
 187   if (pos < argc && argv[pos][0] == '-' && argv[pos][1] == 'o' && !argv[pos][2])
 188     {
 189       advance (0);
 190       v2 = or ();
 191       return (value || v2);
 192     }
 193
 194   return (value);
 195 }
 196
 197 /*
 198  * and:
 199  *      term
 200  *      term '-a' and
 201  */
 202 static int
 203 and ()
 204 {
 205   int value, v2;
 206
 207   value = term ();
 208   if (pos < argc && argv[pos][0] == '-' && argv[pos][1] == 'a' && !argv[pos][2])
 209     {
 210       advance (0);
 211       v2 = and ();
 212       return (value && v2);
 213     }
 214   return (value);
 215 }
 216
 217 /*
 218  * term - parse a term and return 1 or 0 depending on whether the term
 219  *      evaluates to true or false, respectively.
 220  *
 221  * term ::=
 222  *      '-'('a'|'b'|'c'|'d'|'e'|'f'|'g'|'h'|'k'|'p'|'r'|'s'|'u'|'w'|'x') filename
 223  *      '-'('G'|'L'|'O'|'S'|'N') filename
 224  *      '-t' [int]
 225  *      '-'('z'|'n') string
 226  *      '-o' option
 227  *      string
 228  *      string ('!='|'='|'==') string
 229  *      <int> '-'(eq|ne|le|lt|ge|gt) <int>
 230  *      file '-'(nt|ot|ef) file
 231  *      '(' <expr> ')'
 232  * int ::=
 233  *      positive and negative integers
 234  */
 235 static int
 236 term ()
 237 {
 238   int value;
 239
 240   if (pos >= argc)
 241     beyond ();
 242
 243   /* Deal with leading `not's. */
 244   if (argv[pos][0] == '!' && argv[pos][1] == '\0')
 245     {
 246       value = 0;
 247       while (pos < argc && argv[pos][0] == '!' && argv[pos][1] == '\0')
 248         {
 249           advance (1);
 250           value = 1 - value;
 251         }
 252
 253       return (value ? !term() : term());
 254     }
 255
 256   /* A paren-bracketed argument. */
 257   if (argv[pos][0] == '(' && argv[pos][1] == '\0') /* ) */
 258     {
 259       advance (1);
 260       value = expr ();
 261       if (argv[pos] == 0) /* ( */
 262         test_syntax_error (_("`)' expected"), (char *)NULL);
 263       else if (argv[pos][0] != ')' || argv[pos][1]) /* ( */
 264         test_syntax_error (_("`)' expected, found %s"), argv[pos]);
 265       advance (0);
 266       return (value);
 267     }
 268
 269   /* are there enough arguments left that this could be dyadic? */
 270   if ((pos + 3 <= argc) && test_binop (argv[pos + 1]))
 271     value = binary_operator ();
 272
 273   /* Might be a switch type argument */
 274   else if (argv[pos][0] == '-' && argv[pos][2] == '\0')
 275     {
 276       if (test_unop (argv[pos]))
 277         value = unary_operator ();
 278       else
 279         test_syntax_error (_("%s: unary operator expected"), argv[pos]);
 280     }
 281   else
 282     {
 283       value = argv[pos][0] != '\0';
 284       advance (0);
 285     }
 286
 287   return (value);
 288 }
 289
 290 static int
 291 filecomp (s, t, op)
 292      char *s, *t;
 293      int op;
 294 {
 295   struct stat st1, st2;
 296   int r1, r2;
 297
 298   if ((r1 = sh_stat (s, &st1)) < 0)
 299     {
 300       if (op == EF)
 301         return (FALSE);
 302     }
 303   if ((r2 = sh_stat (t, &st2)) < 0)
 304     {
 305       if (op == EF)
 306         return (FALSE);
 307     }
 308
 309   switch (op)
 310     {
 311     case OT: return (r1 < r2 || (r2 == 0 && st1.st_mtime < st2.st_mtime));
 312     case NT: return (r1 > r2 || (r1 == 0 && st1.st_mtime > st2.st_mtime));
 313     case EF: return ((st1.st_dev == st2.st_dev) && (st1.st_ino == st2.st_ino));
 314     }
 315   return (FALSE);
 316 }
 317
 318 static int
 319 arithcomp (s, t, op, flags)
 320      char *s, *t;
 321      int op, flags;
 322 {
 323   intmax_t l, r;
 324   int expok;
 325
 326   if (flags & TEST_ARITHEXP)
 327     {
 328       l = evalexp (s, &expok);
 329       if (expok == 0)
 330         return (FALSE);         /* should probably longjmp here */
 331       r = evalexp (t, &expok);
 332       if (expok == 0)
 333         return (FALSE);         /* ditto */
 334     }
 335   else
 336     {
 337       if (legal_number (s, &l) == 0)
 338         integer_expected_error (s);
 339       if (legal_number (t, &r) == 0)
 340         integer_expected_error (t);
 341     }
 342
 343   switch (op)
 344     {
 345     case EQ: return (l == r);
 346     case NE: return (l != r);
 347     case LT: return (l < r);
 348     case GT: return (l > r);
 349     case LE: return (l <= r);
 350     case GE: return (l >= r);
 351     }
 352
 353   return (FALSE);
 354 }
 355
 356 static int
 357 patcomp (string, pat, op)
 358      char *string, *pat;
 359      int op;
 360 {
 361   int m;
 362
 363   m = strmatch (pat, string, FNMATCH_EXTFLAG|FNMATCH_IGNCASE);
 364   return ((op == EQ) ? (m == 0) : (m != 0));
 365 }
 366
 367 int
 368 binary_test (op, arg1, arg2, flags)
 369      char *op, *arg1, *arg2;
 370      int flags;
 371 {
 372   int patmatch;
 373
 374   patmatch = (flags & TEST_PATMATCH);
 375
 376   if (op[0] == '=' && (op[1] == '\0' || (op[1] == '=' && op[2] == '\0')))
 377     return (patmatch ? patcomp (arg1, arg2, EQ) : STREQ (arg1, arg2));
 378
 379   else if ((op[0] == '>' || op[0] == '<') && op[1] == '\0')
 380     return ((op[0] == '>') ? (strcmp (arg1, arg2) > 0) : (strcmp (arg1, arg2) < 0));
 381
 382   else if (op[0] == '!' && op[1] == '=' && op[2] == '\0')
 383     return (patmatch ? patcomp (arg1, arg2, NE) : (STREQ (arg1, arg2) == 0));
 384
 385   else if (op[2] == 't')
 386     {
 387       switch (op[1])
 388         {
 389         case 'n': return (filecomp (arg1, arg2, NT));           /* -nt */
 390         case 'o': return (filecomp (arg1, arg2, OT));           /* -ot */
 391         case 'l': return (arithcomp (arg1, arg2, LT, flags));   /* -lt */
 392         case 'g': return (arithcomp (arg1, arg2, GT, flags));   /* -gt */
 393         }
 394     }
 395   else if (op[1] == 'e')
 396     {
 397       switch (op[2])
 398         {
 399         case 'f': return (filecomp (arg1, arg2, EF));           /* -ef */
 400         case 'q': return (arithcomp (arg1, arg2, EQ, flags));   /* -eq */
 401         }
 402     }
 403   else if (op[2] == 'e')
 404     {
 405       switch (op[1])
 406         {
 407         case 'n': return (arithcomp (arg1, arg2, NE, flags));   /* -ne */
 408         case 'g': return (arithcomp (arg1, arg2, GE, flags));   /* -ge */
 409         case 'l': return (arithcomp (arg1, arg2, LE, flags));   /* -le */
 410         }
 411     }
 412
 413   return (FALSE);       /* should never get here */
 414 }
 415
 416
 417 static int
 418 binary_operator ()
 419 {
 420   int value;
 421   char *w;
 422
 423   w = argv[pos + 1];
 424   if ((w[0] == '=' && (w[1] == '\0' || (w[1] == '=' && w[2] == '\0'))) || /* =, == */
 425       ((w[0] == '>' || w[0] == '<') && w[1] == '\0') ||         /* <, > */
 426       (w[0] == '!' && w[1] == '=' && w[2] == '\0'))             /* != */
 427     {
 428       value = binary_test (w, argv[pos], argv[pos + 2], 0);
 429       pos += 3;
 430       return (value);
 431     }
 432
 433 #if defined (PATTERN_MATCHING)
 434   if ((w[0] == '=' || w[0] == '!') && w[1] == '~' && w[2] == '\0')
 435     {
 436       value = patcomp (argv[pos], argv[pos + 2], w[0] == '=' ? EQ : NE);
 437       pos += 3;
 438       return (value);
 439     }
 440 #endif
 441
 442   if ((w[0] != '-' || w[3] != '\0') || test_binop (w) == 0)
 443     {
 444       test_syntax_error (_("%s: binary operator expected"), w);
 445       /* NOTREACHED */
 446       return (FALSE);
 447     }
 448
 449   value = binary_test (w, argv[pos], argv[pos + 2], 0);
 450   pos += 3;
 451   return value;
 452 }
 453
 454 static int
 455 unary_operator ()
 456 {
 457   char *op;
 458   intmax_t r;
 459
 460   op = argv[pos];
 461   if (test_unop (op) == 0)
 462     return (FALSE);
 463
 464   /* the only tricky case is `-t', which may or may not take an argument. */
 465   if (op[1] == 't')
 466     {
 467       advance (0);
 468       if (pos < argc)
 469         {
 470           if (legal_number (argv[pos], &r))
 471             {
 472               advance (0);
 473               return (unary_test (op, argv[pos - 1]));
 474             }
 475           else
 476             return (FALSE);
 477         }
 478       else
 479         return (unary_test (op, "1"));
 480     }
 481
 482   /* All of the unary operators take an argument, so we first call
 483      unary_advance (), which checks to make sure that there is an
 484      argument, and then advances pos right past it.  This means that
 485      pos - 1 is the location of the argument. */
 486   unary_advance ();
 487   return (unary_test (op, argv[pos - 1]));
 488 }
 489
 490 int
 491 unary_test (op, arg)
 492      char *op, *arg;
 493 {
 494   intmax_t r;
 495   struct stat stat_buf;
 496
 497   switch (op[1])
 498     {
 499     case 'a':                   /* file exists in the file system? */
 500     case 'e':
 501       return (sh_stat (arg, &stat_buf) == 0);
 502
 503     case 'r':                   /* file is readable? */
 504       return (sh_eaccess (arg, R_OK) == 0);
 505
 506     case 'w':                   /* File is writeable? */
 507       return (sh_eaccess (arg, W_OK) == 0);
 508
 509     case 'x':                   /* File is executable? */
 510       return (sh_eaccess (arg, X_OK) == 0);
 511
 512     case 'O':                   /* File is owned by you? */
 513       return (sh_stat (arg, &stat_buf) == 0 &&
 514               (uid_t) current_user.euid == (uid_t) stat_buf.st_uid);
 515
 516     case 'G':                   /* File is owned by your group? */
 517       return (sh_stat (arg, &stat_buf) == 0 &&
 518               (gid_t) current_user.egid == (gid_t) stat_buf.st_gid);
 519
 520     case 'N':
 521       return (sh_stat (arg, &stat_buf) == 0 &&
 522               stat_buf.st_atime <= stat_buf.st_mtime);
 523
 524     case 'f':                   /* File is a file? */
 525       if (sh_stat (arg, &stat_buf) < 0)
 526         return (FALSE);
 527
 528       /* -f is true if the given file exists and is a regular file. */
 529 #if defined (S_IFMT)
 530       return (S_ISREG (stat_buf.st_mode) || (stat_buf.st_mode & S_IFMT) == 0);
 531 #else
 532       return (S_ISREG (stat_buf.st_mode));
 533 #endif /* !S_IFMT */
 534
 535     case 'd':                   /* File is a directory? */
 536       return (sh_stat (arg, &stat_buf) == 0 && (S_ISDIR (stat_buf.st_mode)));
 537
 538     case 's':                   /* File has something in it? */
 539       return (sh_stat (arg, &stat_buf) == 0 && stat_buf.st_size > (off_t) 0);
 540
 541     case 'S':                   /* File is a socket? */
 542 #if !defined (S_ISSOCK)
 543       return (FALSE);
 544 #else
 545       return (sh_stat (arg, &stat_buf) == 0 && S_ISSOCK (stat_buf.st_mode));
 546 #endif /* S_ISSOCK */
 547
 548     case 'c':                   /* File is character special? */
 549       return (sh_stat (arg, &stat_buf) == 0 && S_ISCHR (stat_buf.st_mode));
 550
 551     case 'b':                   /* File is block special? */
 552       return (sh_stat (arg, &stat_buf) == 0 && S_ISBLK (stat_buf.st_mode));
 553
 554     case 'p':                   /* File is a named pipe? */
 555 #ifndef S_ISFIFO
 556       return (FALSE);
 557 #else
 558       return (sh_stat (arg, &stat_buf) == 0 && S_ISFIFO (stat_buf.st_mode));
 559 #endif /* S_ISFIFO */
 560
 561     case 'L':                   /* Same as -h  */
 562     case 'h':                   /* File is a symbolic link? */
 563 #if !defined (S_ISLNK) || !defined (HAVE_LSTAT)
 564       return (FALSE);
 565 #else
 566       return ((arg[0] != '\0') &&
 567               (lstat (arg, &stat_buf) == 0) && S_ISLNK (stat_buf.st_mode));
 568 #endif /* S_IFLNK && HAVE_LSTAT */
 569
 570     case 'u':                   /* File is setuid? */
 571       return (sh_stat (arg, &stat_buf) == 0 && (stat_buf.st_mode & S_ISUID) != 0);
 572
 573     case 'g':                   /* File is setgid? */
 574       return (sh_stat (arg, &stat_buf) == 0 && (stat_buf.st_mode & S_ISGID) != 0);
 575
 576     case 'k':                   /* File has sticky bit set? */
 577 #if !defined (S_ISVTX)
 578       /* This is not Posix, and is not defined on some Posix systems. */
 579       return (FALSE);
 580 #else
 581       return (sh_stat (arg, &stat_buf) == 0 && (stat_buf.st_mode & S_ISVTX) != 0);
 582 #endif
 583
 584     case 't':   /* File fd is a terminal? */
 585       if (legal_number (arg, &r) == 0)
 586         return (FALSE);
 587       return ((r == (int)r) && isatty ((int)r));
 588
 589     case 'n':                   /* True if arg has some length. */
 590       return (arg[0] != '\0');
 591
 592     case 'z':                   /* True if arg has no length. */
 593       return (arg[0] == '\0');
 594
 595     case 'o':                   /* True if option `arg' is set. */
 596       return (minus_o_option_value (arg) == 1);
 597     }
 598
 599   /* We can't actually get here, but this shuts up gcc. */
 600   return (FALSE);
 601 }
 602
 603 /* Return TRUE if OP is one of the test command's binary operators. */
 604 int
 605 test_binop (op)
 606      char *op;
 607 {
 608   if (op[0] == '=' && op[1] == '\0')
 609     return (1);         /* '=' */
 610   else if ((op[0] == '<' || op[0] == '>') && op[1] == '\0')  /* string <, > */
 611     return (1);
 612   else if ((op[0] == '=' || op[0] == '!') && op[1] == '=' && op[2] == '\0')
 613     return (1);         /* `==' and `!=' */
 614 #if defined (PATTERN_MATCHING)
 615   else if (op[2] == '\0' && op[1] == '~' && (op[0] == '=' || op[0] == '!'))
 616     return (1);
 617 #endif
 618   else if (op[0] != '-' || op[2] == '\0' || op[3] != '\0')
 619     return (0);
 620   else
 621     {
 622       if (op[2] == 't')
 623         switch (op[1])
 624           {
 625           case 'n':             /* -nt */
 626           case 'o':             /* -ot */
 627           case 'l':             /* -lt */
 628           case 'g':             /* -gt */
 629             return (1);
 630           default:
 631             return (0);
 632           }
 633       else if (op[1] == 'e')
 634         switch (op[2])
 635           {
 636           case 'q':             /* -eq */
 637           case 'f':             /* -ef */
 638             return (1);
 639           default:
 640             return (0);
 641           }
 642       else if (op[2] == 'e')
 643         switch (op[1])
 644           {
 645           case 'n':             /* -ne */
 646           case 'g':             /* -ge */
 647           case 'l':             /* -le */
 648             return (1);
 649           default:
 650             return (0);
 651           }
 652       else
 653         return (0);
 654     }
 655 }
 656
 657 /* Return non-zero if OP is one of the test command's unary operators. */
 658 int
 659 test_unop (op)
 660      char *op;
 661 {
 662   if (op[0] != '-')
 663     return (0);
 664
 665   switch (op[1])
 666     {
 667     case 'a': case 'b': case 'c': case 'd': case 'e':
 668     case 'f': case 'g': case 'h': case 'k': case 'n':
 669     case 'o': case 'p': case 'r': case 's': case 't':
 670     case 'u': case 'w': case 'x': case 'z':
 671     case 'G': case 'L': case 'O': case 'S': case 'N':
 672       return (1);
 673     }
 674
 675   return (0);
 676 }
 677
 678 static int
 679 two_arguments ()
 680 {
 681   if (argv[pos][0] == '!' && argv[pos][1] == '\0')
 682     return (argv[pos + 1][0] == '\0');
 683   else if (argv[pos][0] == '-' && argv[pos][2] == '\0')
 684     {
 685       if (test_unop (argv[pos]))
 686         return (unary_operator ());
 687       else
 688         test_syntax_error (_("%s: unary operator expected"), argv[pos]);
 689     }
 690   else
 691     test_syntax_error (_("%s: unary operator expected"), argv[pos]);
 692
 693   return (0);
 694 }
 695
 696 #define ANDOR(s)  (s[0] == '-' && !s[2] && (s[1] == 'a' || s[1] == 'o'))
 697
 698 /* This could be augmented to handle `-t' as equivalent to `-t 1', but
 699    POSIX requires that `-t' be given an argument. */
 700 #define ONE_ARG_TEST(s)         ((s)[0] != '\0')
 701
 702 static int
 703 three_arguments ()
 704 {
 705   int value;
 706
 707   if (test_binop (argv[pos+1]))
 708     {
 709       value = binary_operator ();
 710       pos = argc;
 711     }
 712   else if (ANDOR (argv[pos+1]))
 713     {
 714       if (argv[pos+1][1] == 'a')
 715         value = ONE_ARG_TEST(argv[pos]) && ONE_ARG_TEST(argv[pos+2]);
 716       else
 717         value = ONE_ARG_TEST(argv[pos]) || ONE_ARG_TEST(argv[pos+2]);
 718       pos = argc;
 719     }
 720   else if (argv[pos][0] == '!' && argv[pos][1] == '\0')
 721     {
 722       advance (1);
 723       value = !two_arguments ();
 724     }
 725   else if (argv[pos][0] == '(' && argv[pos+2][0] == ')')
 726     {
 727       value = ONE_ARG_TEST(argv[pos+1]);
 728       pos = argc;
 729     }
 730   else
 731     test_syntax_error (_("%s: binary operator expected"), argv[pos+1]);
 732
 733   return (value);
 734 }
 735
 736 /* This is an implementation of a Posix.2 proposal by David Korn. */
 737 static int
 738 posixtest ()
 739 {
 740   int value;
 741
 742   switch (argc - 1)     /* one extra passed in */
 743     {
 744       case 0:
 745         value = FALSE;
 746         pos = argc;
 747         break;
 748
 749       case 1:
 750         value = ONE_ARG_TEST(argv[1]);
 751         pos = argc;
 752         break;
 753
 754       case 2:
 755         value = two_arguments ();
 756         pos = argc;
 757         break;
 758
 759       case 3:
 760         value = three_arguments ();
 761         break;
 762
 763       case 4:
 764         if (argv[pos][0] == '!' && argv[pos][1] == '\0')
 765           {
 766             advance (1);
 767             value = !three_arguments ();
 768             break;
 769           }
 770         /* FALLTHROUGH */
 771       default:
 772         value = expr ();
 773     }
 774
 775   return (value);
 776 }
 777
 778 /*
 779  * [:
 780  *      '[' expr ']'
 781  * test:
 782  *      test expr
 783  */
 784 int
 785 test_command (margc, margv)
 786      int margc;
 787      char **margv;
 788 {
 789   int value;
 790   int code;
 791
 792   USE_VAR(margc);
 793
 794   code = setjmp (test_exit_buf);
 795
 796   if (code)
 797     return (test_error_return);
 798
 799   argv = margv;
 800
 801   if (margv[0] && margv[0][0] == '[' && margv[0][1] == '\0')
 802     {
 803       --margc;
 804
 805       if (margv[margc] && (margv[margc][0] != ']' || margv[margc][1]))
 806         test_syntax_error (_("missing `]'"), (char *)NULL);
 807
 808       if (margc < 2)
 809         test_exit (SHELL_BOOLEAN (FALSE));
 810     }
 811
 812   argc = margc;
 813   pos = 1;
 814
 815   if (pos >= argc)
 816     test_exit (SHELL_BOOLEAN (FALSE));
 817
 818   noeval = 0;
 819   value = posixtest ();
 820
 821   if (pos != argc)
 822     test_syntax_error (_("too many arguments"), (char *)NULL);
 823
 824   test_exit (SHELL_BOOLEAN (value));
 825 }