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/* GNU test program (ksb and mjb) */

/* Modified to run with the GNU shell by bfox. */

/* Copyright (C) 1987-2003 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 2, or (at your option) any later
   version.

   Bash is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Define TEST_STANDALONE to get the /bin/test version.  Otherwise, you get
   the shell builtin version. */

#include <config.h>
#include <stdio.h>
#include <sys/types.h>

#define TEST_STANDALONE 1

#ifndef LBRACKET
# define LBRACKET 0
#endif

/* The official name of this program (e.g., no `g' prefix).  */
#if LBRACKET
# define PROGRAM_NAME "["
#else
# define PROGRAM_NAME "test"
#endif

#include "system.h"
#include "error.h"
#include "exitfail.h"
#include "euidaccess.h"

#ifndef _POSIX_VERSION
# include <sys/param.h>
#endif /* _POSIX_VERSION */
#define whitespace(c) (((c) == ' ') || ((c) == '\t'))
#define digit(c)  ((c) >= '0' && (c) <= '9')
#define digit_value(c) ((c) - '0')

char *program_name;

#if !defined (_POSIX_VERSION)
# include <sys/file.h>
#endif /* !_POSIX_VERSION */

extern gid_t getegid ();
extern uid_t geteuid ();

#if !defined (R_OK)
# define R_OK 4
# define W_OK 2
# define X_OK 1
# define F_OK 0
#endif /* R_OK */

/* The following few defines control the truth and false output of each stage.
   TRUE and FALSE are what we use to compute the final output value.
   SHELL_BOOLEAN is the form which returns truth or falseness in shell terms.
   TRUTH_OR is how to do logical or with TRUE and FALSE.
   TRUTH_AND is how to do logical and with TRUE and FALSE..
   Default is TRUE = 1, FALSE = 0, TRUTH_OR = a | b, TRUTH_AND = a & b,
    SHELL_BOOLEAN = (!value). */
#define TRUE 1
#define FALSE 0
#define SHELL_BOOLEAN(value) (!(value))
#define TRUTH_OR(a, b) ((a) | (b))
#define TRUTH_AND(a, b) ((a) & (b))

/* Exit status for syntax errors, etc.  */
enum { TEST_FAILURE = 2 };

#if defined (TEST_STANDALONE)
# define test_exit(val) exit (val)
#else
   static jmp_buf test_exit_buf;
   static int test_error_return = 0;
# define test_exit(val) test_error_return = val, longjmp (test_exit_buf, 1)
#endif /* !TEST_STANDALONE */

static int pos;		/* The offset of the current argument in ARGV. */
static int argc;	/* The number of arguments present in ARGV. */
static char **argv;	/* The argument list. */

static int test_unop (char const *s);
static int binop (char *s);
static int unary_operator (void);
static int binary_operator (bool);
static int two_arguments (void);
static int three_arguments (void);
static int posixtest (int);

static int expr (void);
static int term (void);
static int and (void);
static int or (void);

static void test_syntax_error (char const *format, char const *arg)
     ATTRIBUTE_NORETURN;
static void beyond (void) ATTRIBUTE_NORETURN;

static void
test_syntax_error (char const *format, char const *arg)
{
  fprintf (stderr, "%s: ", argv[0]);
  fprintf (stderr, format, arg);
  fflush (stderr);
  test_exit (TEST_FAILURE);
}

#if HAVE_SETREUID && HAVE_SETREGID
/* Do the same thing access(2) does, but use the effective uid and gid.  */

static int
eaccess (char const *file, int mode)
{
  static int have_ids;
  static uid_t uid, euid;
  static gid_t gid, egid;
  int result;

  if (have_ids == 0)
    {
      have_ids = 1;
      uid = getuid ();
      gid = getgid ();
      euid = geteuid ();
      egid = getegid ();
    }

  /* Set the real user and group IDs to the effective ones.  */
  if (uid != euid)
    setreuid (euid, uid);
  if (gid != egid)
    setregid (egid, gid);

  result = access (file, mode);

  /* Restore them.  */
  if (uid != euid)
    setreuid (uid, euid);
  if (gid != egid)
    setregid (gid, egid);

  return result;
}
#else
# define eaccess(F, M) euidaccess (F, M)
#endif

/* Increment our position in the argument list.  Check that we're not
   past the end of the argument list.  This check is supressed if the
   argument is FALSE.  Made a macro for efficiency. */
#define advance(f)							\
  do									\
    {									\
      ++pos;								\
      if ((f) && pos >= argc)						\
	beyond ();							\
    }									\
  while (0)

#if !defined (advance)
static int
advance (int f)
{
  ++pos;

  if (f && pos >= argc)
    beyond ();
}
#endif /* advance */

#define unary_advance()							\
  do									\
    {									\
      advance (1);							\
      ++pos;								\
    }									\
  while (0)

/*
 * beyond - call when we're beyond the end of the argument list (an
 *	error condition)
 */
static void
beyond (void)
{
  test_syntax_error (_("argument expected\n"), NULL);
}

/* Syntax error for when an integer argument was expected, but
   something else was found. */
static void
integer_expected_error (char const *pch)
{
  test_syntax_error (_("%s: integer expression expected\n"), pch);
}

/* Return nonzero if the characters pointed to by STRING constitute a
   valid number.  Stuff the converted number into RESULT if RESULT is
   not null.  */
static int
isint (register char *string, intmax_t *result)
{
  int sign;
  intmax_t value;

  sign = 1;
  value = 0;

  if (result)
    *result = 0;

  /* Skip leading whitespace characters. */
  while (whitespace (*string))
    string++;

  if (!*string)
    return (0);

  /* We allow leading `-' or `+'. */
  if (*string == '-' || *string == '+')
    {
      if (!digit (string[1]))
	return (0);

      if (*string == '-')
	sign = -1;

      string++;
    }

  while (digit (*string))
    {
      if (result)
	value = (value * 10) + digit_value (*string);
      string++;
    }

  /* Skip trailing whitespace, if any. */
  while (whitespace (*string))
    string++;

  /* Error if not at end of string. */
  if (*string)
    return (0);

  if (result)
    {
      value *= sign;
      *result = value;
    }

  return (1);
}

/* Find the modification time of FILE, and stuff it into *AGE.
   Return 0 if successful, -1 if not.  */
static int
age_of (char *filename, time_t *age)
{
  struct stat finfo;
  int r = stat (filename, &finfo);
  if (r == 0)
    *age = finfo.st_mtime;
  return r;
}

/*
 * term - parse a term and return 1 or 0 depending on whether the term
 *	evaluates to true or false, respectively.
 *
 * term ::=
 *	'-'('h'|'d'|'f'|'r'|'s'|'w'|'c'|'b'|'p'|'u'|'g'|'k') filename
 *	'-'('L'|'x') filename
 *	'-t' [ int ]
 *	'-'('z'|'n') string
 *	string
 *	string ('!='|'=') string
 *	<int> '-'(eq|ne|le|lt|ge|gt) <int>
 *	file '-'(nt|ot|ef) file
 *	'(' <expr> ')'
 * int ::=
 *	'-l' string
 *	positive and negative integers
 */
static int
term (void)
{
  int value;

  if (pos >= argc)
    beyond ();

  /* Deal with leading `not's. */
  if (argv[pos][0] == '!' && argv[pos][1] == '\0')
    {
      value = 0;
      while (pos < argc && argv[pos][0] == '!' && argv[pos][1] == '\0')
	{
	  advance (1);
	  value = 1 - value;
	}

      return (value ? !term() : term());
    }

  /* A paren-bracketed argument. */
  if (argv[pos][0] == '(' && argv[pos][1] == '\0')
    {
      int nargs;

      advance (1);

      for (nargs = 1;
	   pos + nargs < argc && ! STREQ (argv[pos + nargs], ")");
	   nargs++)
	if (nargs == 4)
	  {
	    nargs = argc - pos;
	    break;
	  }

      value = posixtest (nargs);
      if (argv[pos] == 0)
	test_syntax_error (_("')' expected\n"), NULL);
      else
        if (argv[pos][0] != ')' || argv[pos][1])
	  test_syntax_error (_("')' expected, found %s\n"), argv[pos]);
      advance (0);
      return (value);
    }

  /* are there enough arguments left that this could be dyadic? */
  if (pos + 4 <= argc && STREQ (argv[pos], "-l") && binop (argv[pos + 2]))
    value = binary_operator (true);
  else if (pos + 3 <= argc && binop (argv[pos + 1]))
    value = binary_operator (false);

  /* Might be a switch type argument */
  else if (argv[pos][0] == '-' && argv[pos][1] && argv[pos][2] == '\0')
    {
      if (test_unop (argv[pos]))
	value = unary_operator ();
      else
	test_syntax_error (_("%s: unary operator expected\n"), argv[pos]);
    }
  else
    {
      value = (argv[pos][0] != '\0');
      advance (0);
    }

  return (value);
}

static int
binary_operator (bool l_is_l)
{
  register int op;
  struct stat stat_buf, stat_spare;
  intmax_t l, r;
  int value;
  /* Is the right integer expression of the form '-l string'? */
  int r_is_l;

  if (l_is_l)
    advance (0);
  op = pos + 1;

  if ((op < argc - 2) && (strcmp (argv[op + 1], "-l") == 0))
    {
      r_is_l = 1;
      advance (0);
    }
  else
    r_is_l = 0;

  if (argv[op][0] == '-')
    {
      /* check for eq, nt, and stuff */
      switch (argv[op][1])
	{
	default:
	  break;

	case 'l':
	  if (argv[op][2] == 't' && !argv[op][3])
	    {
	      /* lt */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -lt"));
		}

	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -lt"));
		}
	      pos += 3;
	      return (TRUE == (l < r));
	    }

	  if (argv[op][2] == 'e' && !argv[op][3])
	    {
	      /* le */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -le"));
		}
	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -le"));
		}
	      pos += 3;
	      return (TRUE == (l <= r));
	    }
	  break;

	case 'g':
	  if (argv[op][2] == 't' && !argv[op][3])
	    {
	      /* gt integer greater than */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -gt"));
		}
	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -gt"));
		}
	      pos += 3;
	      return (TRUE == (l > r));
	    }

	  if (argv[op][2] == 'e' && !argv[op][3])
	    {
	      /* ge - integer greater than or equal to */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -ge"));
		}
	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -ge"));
		}
	      pos += 3;
	      return (TRUE == (l >= r));
	    }
	  break;

	case 'n':
	  if (argv[op][2] == 't' && !argv[op][3])
	    {
	      /* nt - newer than */
	      time_t lt, rt;
	      int le, re;
	      pos += 3;
	      if (l_is_l || r_is_l)
		test_syntax_error (_("-nt does not accept -l\n"), NULL);
	      le = age_of (argv[op - 1], &lt);
	      re = age_of (argv[op + 1], &rt);
	      return le > re || (le == 0 && lt > rt);
	    }

	  if (argv[op][2] == 'e' && !argv[op][3])
	    {
	      /* ne - integer not equal */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -ne"));
		}
	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -ne"));
		}
	      pos += 3;
	      return (TRUE == (l != r));
	    }
	  break;

	case 'e':
	  if (argv[op][2] == 'q' && !argv[op][3])
	    {
	      /* eq - integer equal */
	      if (l_is_l)
		l = strlen (argv[op - 1]);
	      else
		{
		  if (!isint (argv[op - 1], &l))
		    integer_expected_error (_("before -eq"));
		}
	      if (r_is_l)
		r = strlen (argv[op + 2]);
	      else
		{
		  if (!isint (argv[op + 1], &r))
		    integer_expected_error (_("after -eq"));
		}
	      pos += 3;
	      return (TRUE == (l == r));
	    }

	  if (argv[op][2] == 'f' && !argv[op][3])
	    {
	      /* ef - hard link? */
	      pos += 3;
	      if (l_is_l || r_is_l)
		test_syntax_error (_("-ef does not accept -l\n"), NULL);
	      if (stat (argv[op - 1], &stat_buf) < 0)
		return (FALSE);
	      if (stat (argv[op + 1], &stat_spare) < 0)
		return (FALSE);
	      return (TRUE ==
		      (stat_buf.st_dev == stat_spare.st_dev &&
		       stat_buf.st_ino == stat_spare.st_ino));
	    }
	  break;

	case 'o':
	  if ('t' == argv[op][2] && '\000' == argv[op][3])
	    {
	      /* ot - older than */
	      time_t lt, rt;
	      int le, re;
	      pos += 3;
	      if (l_is_l || r_is_l)
		test_syntax_error (_("-ot does not accept -l\n"), NULL);
	      le = age_of (argv[op - 1], &lt);
	      re = age_of (argv[op + 1], &rt);
	      return le < re || (re == 0 && lt < rt);
	    }
	  break;
	}

      /* FIXME: is this dead code? */
      test_syntax_error (_("unknown binary operator\n"), argv[op]);
    }

  if (argv[op][0] == '=' && !argv[op][1])
    {
      value = (strcmp (argv[pos], argv[pos + 2]) == 0);
      pos += 3;
      return (TRUE == value);
    }

  if (strcmp (argv[op], "!=") == 0)
    {
      value = (strcmp (argv[pos], argv[pos + 2]) != 0);
      pos += 3;
      return (TRUE == value);
    }

  /* Not reached.  */
  abort ();
}

static int
unary_operator (void)
{
  int value;
  struct stat stat_buf;

  switch (argv[pos][1])
    {
    default:
      return (FALSE);

      /* All of the following unary operators use unary_advance (), which
	 checks to make sure that there is an argument, and then advances
	 pos right past it.  This means that pos - 1 is the location of the
	 argument. */

    case 'a':			/* file exists in the file system? */
    case 'e':
      unary_advance ();
      value = -1 != stat (argv[pos - 1], &stat_buf);
      return (TRUE == value);

    case 'r':			/* file is readable? */
      unary_advance ();
      value = -1 != eaccess (argv[pos - 1], R_OK);
      return (TRUE == value);

    case 'w':			/* File is writable? */
      unary_advance ();
      value = -1 != eaccess (argv[pos - 1], W_OK);
      return (TRUE == value);

    case 'x':			/* File is executable? */
      unary_advance ();
      value = -1 != eaccess (argv[pos - 1], X_OK);
      return (TRUE == value);

    case 'O':			/* File is owned by you? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (geteuid () == stat_buf.st_uid));

    case 'G':			/* File is owned by your group? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (getegid () == stat_buf.st_gid));

    case 'f':			/* File is a file? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      /* Under POSIX, -f is true if the given file exists
	 and is a regular file. */
      return (TRUE == ((S_ISREG (stat_buf.st_mode)) ||
		       (0 == (stat_buf.st_mode & S_IFMT))));

    case 'd':			/* File is a directory? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (S_ISDIR (stat_buf.st_mode)));

    case 's':			/* File has something in it? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (stat_buf.st_size > (off_t) 0));

    case 'S':			/* File is a socket? */
#if !defined (S_ISSOCK)
      return (FALSE);
#else
      unary_advance ();

      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (S_ISSOCK (stat_buf.st_mode)));
#endif				/* S_ISSOCK */

    case 'c':			/* File is character special? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (S_ISCHR (stat_buf.st_mode)));

    case 'b':			/* File is block special? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (S_ISBLK (stat_buf.st_mode)));

    case 'p':			/* File is a named pipe? */
      unary_advance ();
#ifndef S_ISFIFO
      return (FALSE);
#else
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);
      return (TRUE == (S_ISFIFO (stat_buf.st_mode)));
#endif				/* S_ISFIFO */

    case 'L':			/* Same as -h  */
      /*FALLTHROUGH*/

    case 'h':			/* File is a symbolic link? */
      unary_advance ();
#ifndef S_ISLNK
      return (FALSE);
#else
      /* An empty filename is not a valid pathname. */
      if ((argv[pos - 1][0] == '\0') ||
	  (lstat (argv[pos - 1], &stat_buf) < 0))
	return (FALSE);

      return (TRUE == (S_ISLNK (stat_buf.st_mode)));
#endif				/* S_IFLNK */

    case 'u':			/* File is setuid? */
      unary_advance ();
#ifndef S_ISUID
      return (FALSE);
#else
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (0 != (stat_buf.st_mode & S_ISUID)));
#endif

    case 'g':			/* File is setgid? */
      unary_advance ();
#ifndef S_ISGID
      return (FALSE);
#else
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);

      return (TRUE == (0 != (stat_buf.st_mode & S_ISGID)));
#endif

    case 'k':			/* File has sticky bit set? */
      unary_advance ();
      if (stat (argv[pos - 1], &stat_buf) < 0)
	return (FALSE);
#ifndef S_ISVTX
      /* This is not Posix, and is not defined on some Posix systems. */
      return (FALSE);
#else
      return (TRUE == (0 != (stat_buf.st_mode & S_ISVTX)));
#endif

    case 't':			/* File (fd) is a terminal? */
      {
	intmax_t fd;
	unary_advance ();
	if (!isint (argv[pos - 1], &fd))
	  integer_expected_error (_("after -t"));
	return (TRUE == (fd == (int) fd && isatty (fd)));
      }

    case 'n':			/* True if arg has some length. */
      unary_advance ();
      return (TRUE == (argv[pos - 1][0] != 0));

    case 'z':			/* True if arg has no length. */
      unary_advance ();
      return (TRUE == (argv[pos - 1][0] == '\0'));
    }
}

/*
 * and:
 *	term
 *	term '-a' and
 */
static int
and (void)
{
  int value;

  value = term ();
  while ((pos < argc) && strcmp (argv[pos], "-a") == 0)
    {
      advance (0);
      value = TRUTH_AND (value, and ());
    }
  return (TRUE == value);
}

/*
 * or:
 *	and
 *	and '-o' or
 */
static int
or (void)
{
  int value;

  value = and ();

  while ((pos < argc) && strcmp (argv[pos], "-o") == 0)
    {
      advance (0);
      value = TRUTH_OR (value, or ());
    }

  return (TRUE == value);
}

/*
 * expr:
 *	or
 */
static int
expr (void)
{
  if (pos >= argc)
    beyond ();

  return (FALSE ^ (or ()));		/* Same with this. */
}

/* Return TRUE if S is one of the test command's binary operators. */
static int
binop (char *s)
{
  return ((STREQ (s,   "=")) || (STREQ (s,  "!=")) || (STREQ (s, "-nt")) ||
	  (STREQ (s, "-ot")) || (STREQ (s, "-ef")) || (STREQ (s, "-eq")) ||
	  (STREQ (s, "-ne")) || (STREQ (s, "-lt")) || (STREQ (s, "-le")) ||
	  (STREQ (s, "-gt")) || (STREQ (s, "-ge")));
}

/* Return nonzero if OP is one of the test command's unary operators. */
static int
test_unop (char const *op)
{
  if (op[0] != '-')
    return (0);

  switch (op[1])
    {
    case 'a': case 'b': case 'c': case 'd': case 'e':
    case 'f': case 'g': case 'h': case 'k': case 'n':
    case 'o': case 'p': case 'r': case 's': case 't':
    case 'u': case 'w': case 'x': case 'z':
    case 'G': case 'L': case 'O': case 'S': case 'N':
      return (1);
    }

  return (0);
}

static int
one_argument (void)
{
  return argv[pos++][0] != '\0';
}

static int
two_arguments (void)
{
  int value;

  if (STREQ (argv[pos], "!"))
    {
      advance (0);
      value = ! one_argument ();
    }
  else if (argv[pos][0] == '-'
	   && argv[pos][1] != '\0'
	   && argv[pos][2] == '\0')
    {
      if (test_unop (argv[pos]))
	value = unary_operator ();
      else
	test_syntax_error (_("%s: unary operator expected\n"), argv[pos]);
    }
  else
    beyond ();
  return (value);
}

static int
three_arguments (void)
{
  int value;

  if (binop (argv[pos + 1]))
    value = binary_operator (false);
  else if (STREQ (argv[pos], "!"))
    {
      advance (1);
      value = !two_arguments ();
    }
  else if (STREQ (argv[pos], "(") && STREQ (argv[pos + 2], ")"))
    {
      advance (0);
      value = one_argument ();
      advance (0);
    }
  else if (STREQ (argv[pos + 1], "-a") || STREQ (argv[pos + 1], "-o"))
    value = expr ();
  else
    test_syntax_error (_("%s: binary operator expected\n"), argv[pos+1]);
  return (value);
}

/* This is an implementation of a Posix.2 proposal by David Korn. */
static int
posixtest (int nargs)
{
  int value;

  switch (nargs)
    {
      case 1:
	value = one_argument ();
	break;

      case 2:
	value = two_arguments ();
	break;

      case 3:
	value = three_arguments ();
	break;

      case 4:
	if (STREQ (argv[pos], "!"))
	  {
	    advance (1);
	    value = !three_arguments ();
	    break;
	  }
	if (STREQ (argv[pos], "(") && STREQ (argv[pos + 3], ")"))
	  {
	    advance (0);
	    value = two_arguments ();
	    advance (0);
	    break;
	  }
	/* FALLTHROUGH */
      case 5:
      default:
	if (nargs <= 0)
	  abort ();
	value = expr ();
    }

  return (value);
}

#if defined (TEST_STANDALONE)
# include "long-options.h"

void
usage (int status)
{
  if (status != 0)
    fprintf (stderr, _("Try `%s --help' for more information.\n"),
	     program_name);
  else
    {
      fputs (_("\
Usage: test EXPRESSION\n\
  or:  [ EXPRESSION ]\n\
  or:  [ OPTION\n\
Exit with the status determined by EXPRESSION.\n\
\n\
"), stdout);
      fputs (HELP_OPTION_DESCRIPTION, stdout);
      fputs (VERSION_OPTION_DESCRIPTION, stdout);
      fputs (_("\
\n\
EXPRESSION is true or false and sets exit status.  It is one of:\n\
"), stdout);
      fputs (_("\
\n\
  ( EXPRESSION )               EXPRESSION is true\n\
  ! EXPRESSION                 EXPRESSION is false\n\
  EXPRESSION1 -a EXPRESSION2   both EXPRESSION1 and EXPRESSION2 are true\n\
  EXPRESSION1 -o EXPRESSION2   either EXPRESSION1 or EXPRESSION2 is true\n\
"), stdout);
      fputs (_("\
\n\
  [-n] STRING          the length of STRING is nonzero\n\
  -z STRING            the length of STRING is zero\n\
  STRING1 = STRING2    the strings are equal\n\
  STRING1 != STRING2   the strings are not equal\n\
"), stdout);
      fputs (_("\
\n\
  INTEGER1 -eq INTEGER2   INTEGER1 is equal to INTEGER2\n\
  INTEGER1 -ge INTEGER2   INTEGER1 is greater than or equal to INTEGER2\n\
  INTEGER1 -gt INTEGER2   INTEGER1 is greater than INTEGER2\n\
  INTEGER1 -le INTEGER2   INTEGER1 is less than or equal to INTEGER2\n\
  INTEGER1 -lt INTEGER2   INTEGER1 is less than INTEGER2\n\
  INTEGER1 -ne INTEGER2   INTEGER1 is not equal to INTEGER2\n\
"), stdout);
      fputs (_("\
\n\
  FILE1 -ef FILE2   FILE1 and FILE2 have the same device and inode numbers\n\
  FILE1 -nt FILE2   FILE1 is newer (modification date) than FILE2\n\
  FILE1 -ot FILE2   FILE1 is older than FILE2\n\
"), stdout);
      fputs (_("\
\n\
  -b FILE     FILE exists and is block special\n\
  -c FILE     FILE exists and is character special\n\
  -d FILE     FILE exists and is a directory\n\
  -e FILE     FILE exists\n\
"), stdout);
      fputs (_("\
  -f FILE     FILE exists and is a regular file\n\
  -g FILE     FILE exists and is set-group-ID\n\
  -h FILE     FILE exists and is a symbolic link (same as -L)\n\
  -G FILE     FILE exists and is owned by the effective group ID\n\
  -k FILE     FILE exists and has its sticky bit set\n\
"), stdout);
      fputs (_("\
  -L FILE     FILE exists and is a symbolic link (same as -h)\n\
  -O FILE     FILE exists and is owned by the effective user ID\n\
  -p FILE     FILE exists and is a named pipe\n\
  -r FILE     FILE exists and is readable\n\
  -s FILE     FILE exists and has a size greater than zero\n\
"), stdout);
      fputs (_("\
  -S FILE     FILE exists and is a socket\n\
  -t [FD]     file descriptor FD (stdout by default) is opened on a terminal\n\
  -u FILE     FILE exists and its set-user-ID bit is set\n\
  -w FILE     FILE exists and is writable\n\
  -x FILE     FILE exists and is executable\n\
"), stdout);
      fputs (_("\
\n\
Beware that parentheses need to be escaped (e.g., by backslashes) for shells.\n\
INTEGER may also be -l STRING, which evaluates to the length of STRING.\n\
"), stdout);
      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    }
  exit (status);
}
#endif /* TEST_STANDALONE */

#if !defined (TEST_STANDALONE)
# define main test_command
#endif

#define AUTHORS "Kevin Braunsdorf", "Matthew Bradburn"

/*
 * [:
 *	'[' expr ']'
 * test:
 *	test expr
 */
int
main (int margc, char **margv)
{
  int value;

#if !defined (TEST_STANDALONE)
  int code;

  code = setjmp (test_exit_buf);

  if (code)
    return (test_error_return);
#else /* TEST_STANDALONE */
  initialize_main (&margc, &margv);
  program_name = margv[0];
  setlocale (LC_ALL, "");
  bindtextdomain (PACKAGE, LOCALEDIR);
  textdomain (PACKAGE);

  exit_failure = TEST_FAILURE;
  atexit (close_stdout);
#endif /* TEST_STANDALONE */

  argv = margv;

  if (LBRACKET)
    {
      /* Recognize --help or --version, but only when invoked in the
	 "[" form, and when the last argument is not "]".  POSIX
	 allows "[ --help" and "[ --version" to have the usual GNU
	 behavior, but it requires "test --help" and "test --version"
	 to exit silently with status 1.  */
      if (margc < 2 || strcmp (margv[margc - 1], "]") != 0)
	{
	  parse_long_options (margc, margv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
			      usage, AUTHORS, NULL);
	  test_syntax_error (_("missing `]'\n"), NULL);
	}

      --margc;
    }

  argc = margc;
  pos = 1;

  if (pos >= argc)
    test_exit (SHELL_BOOLEAN (FALSE));

  value = posixtest (argc - 1);

  if (pos != argc)
    test_syntax_error (_("too many arguments\n"), NULL);

  test_exit (SHELL_BOOLEAN (value));
}