--- /dev/null
+.\" $NetBSD: test.1,v 1.27 2009/11/10 18:19:46 wiz Exp $
+.\"
+.\" Copyright (c) 1991, 1993
+.\" The Regents of the University of California. All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Institute of Electrical and Electronics Engineers, Inc.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in the
+.\" documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)test.1 8.1 (Berkeley) 5/31/93
+.\"
+.Dd November 10, 2009
+.Dt TEST 1
+.Os
+.Sh NAME
+.Nm test ,
+.Nm \&[
+.Nd condition evaluation utility
+.Sh SYNOPSIS
+.Nm test
+.Ar expression
+.Nm \&[
+.Ar expression Cm \&]
+.Sh DESCRIPTION
+The
+.Nm test
+utility evaluates
+.Ar expression
+and, if it evaluates
+to true, returns a zero (true) exit status; otherwise
+it returns 1 (false).
+If
+.Ar expression
+is not given,
+.Nm test
+also
+returns 1 (false).
+.Pp
+All operators and flags are separate arguments to the
+.Nm test
+utility.
+.Pp
+The following primaries are used to construct
+.Ar expression :
+.Bl -tag -width Ar
+.It Fl b Ar file
+True if
+.Ar file
+exists and is a block special
+file.
+.It Fl c Ar file
+True if
+.Ar file
+exists and is a character
+special file.
+.It Fl d Ar file
+True if
+.Ar file
+exists and is a directory.
+.It Fl e Ar file
+True if
+.Ar file
+exists (regardless of type).
+.It Fl f Ar file
+True if
+.Ar file
+exists and is a regular file.
+.It Fl g Ar file
+True if
+.Ar file
+exists and its set group ID flag
+is set.
+.It Fl h Ar file
+True if
+.Ar file
+exists and is a symbolic link.
+.It Fl k Ar file
+True if
+.Ar file
+exists and its sticky bit is set.
+.It Fl n Ar string
+True if the length of
+.Ar string
+is nonzero.
+.It Fl p Ar file
+True if
+.Ar file
+exists and is a named pipe
+.Po Tn FIFO Pc .
+.It Fl r Ar file
+True if
+.Ar file
+exists and is readable.
+.It Fl s Ar file
+True if
+.Ar file
+exists and has a size greater
+than zero.
+.It Fl t Ar file_descriptor
+True if the file whose file descriptor number
+is
+.Ar file_descriptor
+is open and is associated with a terminal.
+.It Fl u Ar file
+True if
+.Ar file
+exists and its set user ID flag
+is set.
+.It Fl w Ar file
+True if
+.Ar file
+exists and is writable.
+True
+indicates only that the write flag is on.
+The file is not writable on a read-only file
+system even if this test indicates true.
+.It Fl x Ar file
+True if
+.Ar file
+exists and is executable.
+True
+indicates only that the execute flag is on.
+If
+.Ar file
+is a directory, true indicates that
+.Ar file
+can be searched.
+.It Fl z Ar string
+True if the length of
+.Ar string
+is zero.
+.It Fl L Ar file
+True if
+.Ar file
+exists and is a symbolic link.
+This operator is retained for compatibility with previous versions of
+this program.
+Do not rely on its existence; use
+.Fl h
+instead.
+.It Fl O Ar file
+True if
+.Ar file
+exists and its owner matches the effective user id of this process.
+.It Fl G Ar file
+True if
+.Ar file
+exists and its group matches the effective group id of this process.
+.It Fl S Ar file
+True if
+.Ar file
+exists and is a socket.
+.It Ar file1 Fl nt Ar file2
+True if
+.Ar file1
+exists and is newer than
+.Ar file2 .
+.It Ar file1 Fl ot Ar file2
+True if
+.Ar file1
+exists and is older than
+.Ar file2 .
+.It Ar file1 Fl ef Ar file2
+True if
+.Ar file1
+and
+.Ar file2
+exist and refer to the same file.
+.It Ar string
+True if
+.Ar string
+is not the null
+string.
+.It Ar \&s\&1 Cm \&= Ar \&s\&2
+True if the strings
+.Ar \&s\&1
+and
+.Ar \&s\&2
+are identical.
+.It Ar \&s\&1 Cm \&!= Ar \&s\&2
+True if the strings
+.Ar \&s\&1
+and
+.Ar \&s\&2
+are not identical.
+.It Ar \&s\&1 Cm \&\*[Lt] Ar \&s\&2
+True if string
+.Ar \&s\&1
+comes before
+.Ar \&s\&2
+based on the ASCII value of their characters.
+.It Ar \&s\&1 Cm \&\*[Gt] Ar \&s\&2
+True if string
+.Ar \&s\&1
+comes after
+.Ar \&s\&2
+based on the ASCII value of their characters.
+.It Ar \&n\&1 Fl \&eq Ar \&n\&2
+True if the integers
+.Ar \&n\&1
+and
+.Ar \&n\&2
+are algebraically
+equal.
+.It Ar \&n\&1 Fl \&ne Ar \&n\&2
+True if the integers
+.Ar \&n\&1
+and
+.Ar \&n\&2
+are not
+algebraically equal.
+.It Ar \&n\&1 Fl \> Ar \&n\&2
+True if the integer
+.Ar \&n\&1
+is algebraically
+greater than the integer
+.Ar \&n\&2 .
+.It Ar \&n\&1 Fl \&ge Ar \&n\&2
+True if the integer
+.Ar \&n\&1
+is algebraically
+greater than or equal to the integer
+.Ar \&n\&2 .
+.It Ar \&n\&1 Fl \< Ar \&n\&2
+True if the integer
+.Ar \&n\&1
+is algebraically less
+than the integer
+.Ar \&n\&2 .
+.It Ar \&n\&1 Fl \&le Ar \&n\&2
+True if the integer
+.Ar \&n\&1
+is algebraically less
+than or equal to the integer
+.Ar \&n\&2 .
+.El
+.Pp
+These primaries can be combined with the following operators:
+.Bl -tag -width Ar
+.It Cm \&! Ar expression
+True if
+.Ar expression
+is false.
+.It Ar expression1 Fl a Ar expression2
+True if both
+.Ar expression1
+and
+.Ar expression2
+are true.
+.It Ar expression1 Fl o Ar expression2
+True if either
+.Ar expression1
+or
+.Ar expression2
+are true.
+.It Cm \&( Ar expression Cm \&)
+True if
+.Ar expression
+is true.
+.El
+.Pp
+The
+.Fl a
+operator has higher precedence than the
+.Fl o
+operator.
+.Pp
+Note that all file tests with the exception of
+.Fl h
+and
+.Fl L
+follow symbolic links and thus evaluate the test for the file pointed at.
+.Sh GRAMMAR AMBIGUITY
+The
+.Nm test
+grammar is inherently ambiguous.
+In order to assure a degree of consistency, the cases described in
+.St -p1003.2
+section 4.62.4,
+are evaluated consistently according to the rules specified in the
+standards document.
+All other cases are subject to the ambiguity in the command semantics.
+.Sh EXIT STATUS
+The
+.Nm test
+utility exits with one of the following values:
+.Bl -tag -width Ds
+.It 0
+.Ar expression
+evaluated to true.
+.It 1
+.Ar expression
+evaluated to false or was missing.
+.It \*[Gt]1
+An error occurred.
+.El
+.Sh STANDARDS
+The
+.Nm test
+utility implements a superset of the
+.St -p1003.2
+specification.
--- /dev/null
+/* $NetBSD: test.c,v 1.39 2012/03/15 02:02:21 joerg Exp $ */
+
+/*
+ * test(1); version 7-like -- author Erik Baalbergen
+ * modified by Eric Gisin to be used as built-in.
+ * modified by Arnold Robbins to add SVR3 compatibility
+ * (-x -c -b -p -u -g -k) plus Korn's -L -nt -ot -ef and new -S (socket).
+ * modified by J.T. Conklin for NetBSD.
+ *
+ * This program is in the Public Domain.
+ */
+
+#include <sys/cdefs.h>
+#ifndef lint
+__RCSID("$NetBSD: test.c,v 1.39 2012/03/15 02:02:21 joerg Exp $");
+#endif
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdarg.h>
+
+/* test(1) accepts the following grammar:
+ oexpr ::= aexpr | aexpr "-o" oexpr ;
+ aexpr ::= nexpr | nexpr "-a" aexpr ;
+ nexpr ::= primary | "!" primary
+ primary ::= unary-operator operand
+ | operand binary-operator operand
+ | operand
+ | "(" oexpr ")"
+ ;
+ unary-operator ::= "-r"|"-w"|"-x"|"-f"|"-d"|"-c"|"-b"|"-p"|
+ "-u"|"-g"|"-k"|"-s"|"-t"|"-z"|"-n"|"-o"|"-O"|"-G"|"-L"|"-S";
+
+ binary-operator ::= "="|"!="|"-eq"|"-ne"|"-ge"|"-gt"|"-le"|"-lt"|
+ "-nt"|"-ot"|"-ef";
+ operand ::= <any legal UNIX file name>
+*/
+
+enum token {
+ EOI,
+ FILRD,
+ FILWR,
+ FILEX,
+ FILEXIST,
+ FILREG,
+ FILDIR,
+ FILCDEV,
+ FILBDEV,
+ FILFIFO,
+ FILSOCK,
+ FILSYM,
+ FILGZ,
+ FILTT,
+ FILSUID,
+ FILSGID,
+ FILSTCK,
+ FILNT,
+ FILOT,
+ FILEQ,
+ FILUID,
+ FILGID,
+ STREZ,
+ STRNZ,
+ STREQ,
+ STRNE,
+ STRLT,
+ STRGT,
+ INTEQ,
+ INTNE,
+ INTGE,
+ INTGT,
+ INTLE,
+ INTLT,
+ UNOT,
+ BAND,
+ BOR,
+ LPAREN,
+ RPAREN,
+ OPERAND
+};
+
+enum token_types {
+ UNOP,
+ BINOP,
+ BUNOP,
+ BBINOP,
+ PAREN
+};
+
+struct t_op {
+ const char *op_text;
+ short op_num, op_type;
+};
+
+static const struct t_op cop[] = {
+ {"!", UNOT, BUNOP},
+ {"(", LPAREN, PAREN},
+ {")", RPAREN, PAREN},
+ {"<", STRLT, BINOP},
+ {"=", STREQ, BINOP},
+ {">", STRGT, BINOP},
+};
+
+static const struct t_op cop2[] = {
+ {"!=", STRNE, BINOP},
+};
+
+static const struct t_op mop3[] = {
+ {"ef", FILEQ, BINOP},
+ {"eq", INTEQ, BINOP},
+ {"ge", INTGE, BINOP},
+ {"gt", INTGT, BINOP},
+ {"le", INTLE, BINOP},
+ {"lt", INTLT, BINOP},
+ {"ne", INTNE, BINOP},
+ {"nt", FILNT, BINOP},
+ {"ot", FILOT, BINOP},
+};
+
+static const struct t_op mop2[] = {
+ {"G", FILGID, UNOP},
+ {"L", FILSYM, UNOP},
+ {"O", FILUID, UNOP},
+ {"S", FILSOCK,UNOP},
+ {"a", BAND, BBINOP},
+ {"b", FILBDEV,UNOP},
+ {"c", FILCDEV,UNOP},
+ {"d", FILDIR, UNOP},
+ {"e", FILEXIST,UNOP},
+ {"f", FILREG, UNOP},
+ {"g", FILSGID,UNOP},
+ {"h", FILSYM, UNOP}, /* for backwards compat */
+ {"k", FILSTCK,UNOP},
+ {"n", STRNZ, UNOP},
+ {"o", BOR, BBINOP},
+ {"p", FILFIFO,UNOP},
+ {"r", FILRD, UNOP},
+ {"s", FILGZ, UNOP},
+ {"t", FILTT, UNOP},
+ {"u", FILSUID,UNOP},
+ {"w", FILWR, UNOP},
+ {"x", FILEX, UNOP},
+ {"z", STREZ, UNOP},
+};
+
+static char **t_wp;
+static struct t_op const *t_wp_op;
+
+__dead static void syntax(const char *, const char *);
+static int oexpr(enum token);
+static int aexpr(enum token);
+static int nexpr(enum token);
+static int primary(enum token);
+static int binop(void);
+static int test_access(struct stat *, mode_t);
+static int filstat(char *, enum token);
+static enum token t_lex(char *);
+static int isoperand(void);
+static long long getn(const char *);
+static int newerf(const char *, const char *);
+static int olderf(const char *, const char *);
+static int equalf(const char *, const char *);
+
+#if defined(SHELL)
+extern void error(const char *, ...) __dead __printflike(1, 2);
+extern void *ckmalloc(size_t);
+#else
+static void error(const char *, ...) __dead __printflike(1, 2);
+
+static void
+error(const char *msg, ...)
+{
+ va_list ap;
+
+ va_start(ap, msg);
+ verrx(2, msg, ap);
+ /*NOTREACHED*/
+ va_end(ap);
+}
+
+static void *ckmalloc(size_t);
+static void *
+ckmalloc(size_t nbytes)
+{
+ void *p = malloc(nbytes);
+
+ if (!p)
+ error("Not enough memory!");
+ return p;
+}
+#endif
+
+#ifdef SHELL
+int testcmd(int, char **);
+
+int
+testcmd(int argc, char **argv)
+#else
+int main(int, char *[]);
+
+int
+main(int argc, char *argv[])
+#endif
+{
+ int res;
+ const char *argv0;
+
+#ifdef SHELL
+ argv0 = argv[0];
+#else
+ setprogname(argv[0]);
+ (void)setlocale(LC_ALL, "");
+ argv0 = getprogname();
+#endif
+ if (strcmp(argv0, "[") == 0) {
+ if (strcmp(argv[--argc], "]"))
+ error("missing ]");
+ argv[argc] = NULL;
+ }
+
+ if (argc < 2)
+ return 1;
+
+ t_wp = &argv[1];
+ res = !oexpr(t_lex(*t_wp));
+
+ if (*t_wp != NULL && *++t_wp != NULL)
+ syntax(*t_wp, "unexpected operator");
+
+ return res;
+}
+
+static void
+syntax(const char *op, const char *msg)
+{
+
+ if (op && *op)
+ error("%s: %s", op, msg);
+ else
+ error("%s", msg);
+}
+
+static int
+oexpr(enum token n)
+{
+ int res;
+
+ res = aexpr(n);
+ if (*t_wp == NULL)
+ return res;
+ if (t_lex(*++t_wp) == BOR)
+ return oexpr(t_lex(*++t_wp)) || res;
+ t_wp--;
+ return res;
+}
+
+static int
+aexpr(enum token n)
+{
+ int res;
+
+ res = nexpr(n);
+ if (*t_wp == NULL)
+ return res;
+ if (t_lex(*++t_wp) == BAND)
+ return aexpr(t_lex(*++t_wp)) && res;
+ t_wp--;
+ return res;
+}
+
+static int
+nexpr(enum token n)
+{
+
+ if (n == UNOT)
+ return !nexpr(t_lex(*++t_wp));
+ return primary(n);
+}
+
+static int
+primary(enum token n)
+{
+ enum token nn;
+ int res;
+
+ if (n == EOI)
+ return 0; /* missing expression */
+ if (n == LPAREN) {
+ if ((nn = t_lex(*++t_wp)) == RPAREN)
+ return 0; /* missing expression */
+ res = oexpr(nn);
+ if (t_lex(*++t_wp) != RPAREN)
+ syntax(NULL, "closing paren expected");
+ return res;
+ }
+ if (t_wp_op && t_wp_op->op_type == UNOP) {
+ /* unary expression */
+ if (*++t_wp == NULL)
+ syntax(t_wp_op->op_text, "argument expected");
+ switch (n) {
+ case STREZ:
+ return strlen(*t_wp) == 0;
+ case STRNZ:
+ return strlen(*t_wp) != 0;
+ case FILTT:
+ return isatty((int)getn(*t_wp));
+ default:
+ return filstat(*t_wp, n);
+ }
+ }
+
+ if (t_lex(t_wp[1]), t_wp_op && t_wp_op->op_type == BINOP) {
+ return binop();
+ }
+
+ return strlen(*t_wp) > 0;
+}
+
+static int
+binop(void)
+{
+ const char *opnd1, *opnd2;
+ struct t_op const *op;
+
+ opnd1 = *t_wp;
+ (void) t_lex(*++t_wp);
+ op = t_wp_op;
+
+ if ((opnd2 = *++t_wp) == NULL)
+ syntax(op->op_text, "argument expected");
+
+ switch (op->op_num) {
+ case STREQ:
+ return strcmp(opnd1, opnd2) == 0;
+ case STRNE:
+ return strcmp(opnd1, opnd2) != 0;
+ case STRLT:
+ return strcmp(opnd1, opnd2) < 0;
+ case STRGT:
+ return strcmp(opnd1, opnd2) > 0;
+ case INTEQ:
+ return getn(opnd1) == getn(opnd2);
+ case INTNE:
+ return getn(opnd1) != getn(opnd2);
+ case INTGE:
+ return getn(opnd1) >= getn(opnd2);
+ case INTGT:
+ return getn(opnd1) > getn(opnd2);
+ case INTLE:
+ return getn(opnd1) <= getn(opnd2);
+ case INTLT:
+ return getn(opnd1) < getn(opnd2);
+ case FILNT:
+ return newerf(opnd1, opnd2);
+ case FILOT:
+ return olderf(opnd1, opnd2);
+ case FILEQ:
+ return equalf(opnd1, opnd2);
+ default:
+ abort();
+ /* NOTREACHED */
+ }
+}
+
+/*
+ * The manual, and IEEE POSIX 1003.2, suggests this should check the mode bits,
+ * not use access():
+ *
+ * True shall indicate only that the write flag is on. The file is not
+ * writable on a read-only file system even if this test indicates true.
+ *
+ * Unfortunately IEEE POSIX 1003.1-2001, as quoted in SuSv3, says only:
+ *
+ * True shall indicate that permission to read from file will be granted,
+ * as defined in "File Read, Write, and Creation".
+ *
+ * and that section says:
+ *
+ * When a file is to be read or written, the file shall be opened with an
+ * access mode corresponding to the operation to be performed. If file
+ * access permissions deny access, the requested operation shall fail.
+ *
+ * and of course access permissions are described as one might expect:
+ *
+ * * If a process has the appropriate privilege:
+ *
+ * * If read, write, or directory search permission is requested,
+ * access shall be granted.
+ *
+ * * If execute permission is requested, access shall be granted if
+ * execute permission is granted to at least one user by the file
+ * permission bits or by an alternate access control mechanism;
+ * otherwise, access shall be denied.
+ *
+ * * Otherwise:
+ *
+ * * The file permission bits of a file contain read, write, and
+ * execute/search permissions for the file owner class, file group
+ * class, and file other class.
+ *
+ * * Access shall be granted if an alternate access control mechanism
+ * is not enabled and the requested access permission bit is set for
+ * the class (file owner class, file group class, or file other class)
+ * to which the process belongs, or if an alternate access control
+ * mechanism is enabled and it allows the requested access; otherwise,
+ * access shall be denied.
+ *
+ * and when I first read this I thought: surely we can't go about using
+ * open(O_WRONLY) to try this test! However the POSIX 1003.1-2001 Rationale
+ * section for test does in fact say:
+ *
+ * On historical BSD systems, test -w directory always returned false
+ * because test tried to open the directory for writing, which always
+ * fails.
+ *
+ * and indeed this is in fact true for Seventh Edition UNIX, UNIX 32V, and UNIX
+ * System III, and thus presumably also for BSD up to and including 4.3.
+ *
+ * Secondly I remembered why using open() and/or access() are bogus. They
+ * don't work right for detecting read and write permissions bits when called
+ * by root.
+ *
+ * Interestingly the 'test' in 4.4BSD was closer to correct (as per
+ * 1003.2-1992) and it was implemented efficiently with stat() instead of
+ * open().
+ *
+ * This was apparently broken in NetBSD around about 1994/06/30 when the old
+ * 4.4BSD implementation was replaced with a (arguably much better coded)
+ * implementation derived from pdksh.
+ *
+ * Note that modern pdksh is yet different again, but still not correct, at
+ * least not w.r.t. 1003.2-1992.
+ *
+ * As I think more about it and read more of the related IEEE docs I don't like
+ * that wording about 'test -r' and 'test -w' in 1003.1-2001 at all. I very
+ * much prefer the original wording in 1003.2-1992. It is much more useful,
+ * and so that's what I've implemented.
+ *
+ * (Note that a strictly conforming implementation of 1003.1-2001 is in fact
+ * totally useless for the case in question since its 'test -w' and 'test -r'
+ * can never fail for root for any existing files, i.e. files for which 'test
+ * -e' succeeds.)
+ *
+ * The rationale for 1003.1-2001 suggests that the wording was "clarified" in
+ * 1003.1-2001 to align with the 1003.2b draft. 1003.2b Draft 12 (July 1999),
+ * which is the latest copy I have, does carry the same suggested wording as is
+ * in 1003.1-2001, with its rationale saying:
+ *
+ * This change is a clarification and is the result of interpretation
+ * request PASC 1003.2-92 #23 submitted for IEEE Std 1003.2-1992.
+ *
+ * That interpretation can be found here:
+ *
+ * http://www.pasc.org/interps/unofficial/db/p1003.2/pasc-1003.2-23.html
+ *
+ * Not terribly helpful, unfortunately. I wonder who that fence sitter was.
+ *
+ * Worse, IMVNSHO, I think the authors of 1003.2b-D12 have mis-interpreted the
+ * PASC interpretation and appear to be gone against at least one widely used
+ * implementation (namely 4.4BSD). The problem is that for file access by root
+ * this means that if test '-r' and '-w' are to behave as if open() were called
+ * then there's no way for a shell script running as root to check if a file
+ * has certain access bits set other than by the grotty means of interpreting
+ * the output of 'ls -l'. This was widely considered to be a bug in V7's
+ * "test" and is, I believe, one of the reasons why direct use of access() was
+ * avoided in some more recent implementations!
+ *
+ * I have always interpreted '-r' to match '-w' and '-x' as per the original
+ * wording in 1003.2-1992, not the other way around. I think 1003.2b goes much
+ * too far the wrong way without any valid rationale and that it's best if we
+ * stick with 1003.2-1992 and test the flags, and not mimic the behaviour of
+ * open() since we already know very well how it will work -- existance of the
+ * file is all that matters to open() for root.
+ *
+ * Unfortunately the SVID is no help at all (which is, I guess, partly why
+ * we're in this mess in the first place :-).
+ *
+ * The SysV implementation (at least in the 'test' builtin in /bin/sh) does use
+ * access(name, 2) even though it also goes to much greater lengths for '-x'
+ * matching the 1003.2-1992 definition (which is no doubt where that definition
+ * came from).
+ *
+ * The ksh93 implementation uses access() for '-r' and '-w' if
+ * (euid==uid&&egid==gid), but uses st_mode for '-x' iff running as root.
+ * i.e. it does strictly conform to 1003.1-2001 (and presumably 1003.2b).
+ */
+static int
+test_access(struct stat *sp, mode_t stmode)
+{
+ gid_t *groups;
+ register int n;
+ uid_t euid;
+ int maxgroups;
+
+ /*
+ * I suppose we could use access() if not running as root and if we are
+ * running with ((euid == uid) && (egid == gid)), but we've already
+ * done the stat() so we might as well just test the permissions
+ * directly instead of asking the kernel to do it....
+ */
+ euid = geteuid();
+ if (euid == 0) /* any bit is good enough */
+ stmode = (stmode << 6) | (stmode << 3) | stmode;
+ else if (sp->st_uid == euid)
+ stmode <<= 6;
+ else if (sp->st_gid == getegid())
+ stmode <<= 3;
+ else {
+ /* XXX stolen almost verbatim from ksh93.... */
+ /* on some systems you can be in several groups */
+ if ((maxgroups = getgroups(0, NULL)) <= 0)
+ maxgroups = NGROUPS_MAX; /* pre-POSIX system? */
+ groups = ckmalloc((maxgroups + 1) * sizeof(gid_t));
+ n = getgroups(maxgroups, groups);
+ while (--n >= 0) {
+ if (groups[n] == sp->st_gid) {
+ stmode <<= 3;
+ break;
+ }
+ }
+ free(groups);
+ }
+
+ return sp->st_mode & stmode;
+}
+
+static int
+filstat(char *nm, enum token mode)
+{
+ struct stat s;
+
+ if (mode == FILSYM ? lstat(nm, &s) : stat(nm, &s))
+ return 0;
+
+ switch (mode) {
+ case FILRD:
+ return test_access(&s, S_IROTH);
+ case FILWR:
+ return test_access(&s, S_IWOTH);
+ case FILEX:
+ return test_access(&s, S_IXOTH);
+ case FILEXIST:
+ return 1; /* the successful lstat()/stat() is good enough */
+ case FILREG:
+ return S_ISREG(s.st_mode);
+ case FILDIR:
+ return S_ISDIR(s.st_mode);
+ case FILCDEV:
+ return S_ISCHR(s.st_mode);
+ case FILBDEV:
+ return S_ISBLK(s.st_mode);
+ case FILFIFO:
+ return S_ISFIFO(s.st_mode);
+ case FILSOCK:
+ return S_ISSOCK(s.st_mode);
+ case FILSYM:
+ return S_ISLNK(s.st_mode);
+ case FILSUID:
+ return (s.st_mode & S_ISUID) != 0;
+ case FILSGID:
+ return (s.st_mode & S_ISGID) != 0;
+ case FILSTCK:
+ return (s.st_mode & S_ISVTX) != 0;
+ case FILGZ:
+ return s.st_size > (off_t)0;
+ case FILUID:
+ return s.st_uid == geteuid();
+ case FILGID:
+ return s.st_gid == getegid();
+ default:
+ return 1;
+ }
+}
+
+#define VTOC(x) (const unsigned char *)((const struct t_op *)x)->op_text
+
+static int
+compare1(const void *va, const void *vb)
+{
+ const unsigned char *a = va;
+ const unsigned char *b = VTOC(vb);
+
+ return a[0] - b[0];
+}
+
+static int
+compare2(const void *va, const void *vb)
+{
+ const unsigned char *a = va;
+ const unsigned char *b = VTOC(vb);
+ int z = a[0] - b[0];
+
+ return z ? z : (a[1] - b[1]);
+}
+
+static struct t_op const *
+findop(const char *s)
+{
+ if (s[0] == '-') {
+ if (s[1] == '\0')
+ return NULL;
+ if (s[2] == '\0')
+ return bsearch(s + 1, mop2, __arraycount(mop2),
+ sizeof(*mop2), compare1);
+ else if (s[3] != '\0')
+ return NULL;
+ else
+ return bsearch(s + 1, mop3, __arraycount(mop3),
+ sizeof(*mop3), compare2);
+ } else {
+ if (s[1] == '\0')
+ return bsearch(s, cop, __arraycount(cop), sizeof(*cop),
+ compare1);
+ else if (strcmp(s, cop2[0].op_text) == 0)
+ return cop2;
+ else
+ return NULL;
+ }
+}
+
+static enum token
+t_lex(char *s)
+{
+ struct t_op const *op;
+
+ if (s == NULL) {
+ t_wp_op = NULL;
+ return EOI;
+ }
+
+ if ((op = findop(s)) != NULL) {
+ if (!((op->op_type == UNOP && isoperand()) ||
+ (op->op_num == LPAREN && *(t_wp+1) == 0))) {
+ t_wp_op = op;
+ return op->op_num;
+ }
+ }
+ t_wp_op = NULL;
+ return OPERAND;
+}
+
+static int
+isoperand(void)
+{
+ struct t_op const *op;
+ char *s, *t;
+
+ if ((s = *(t_wp+1)) == 0)
+ return 1;
+ if ((t = *(t_wp+2)) == 0)
+ return 0;
+ if ((op = findop(s)) != NULL)
+ return op->op_type == BINOP && (t[0] != ')' || t[1] != '\0');
+ return 0;
+}
+
+/* atoi with error detection */
+static long long
+getn(const char *s)
+{
+ char *p;
+ long long r;
+
+ errno = 0;
+ r = strtoll(s, &p, 10);
+
+ if (errno != 0)
+ if (errno == ERANGE && (r == LLONG_MAX || r == LLONG_MIN))
+ error("%s: out of range", s);
+
+ while (isspace((unsigned char)*p))
+ p++;
+
+ if (*p || p == s)
+ error("%s: bad number", s);
+
+ return r;
+}
+
+static int
+newerf(const char *f1, const char *f2)
+{
+ struct stat b1, b2;
+
+ return (stat(f1, &b1) == 0 &&
+ stat(f2, &b2) == 0 &&
+ b1.st_mtime > b2.st_mtime);
+}
+
+static int
+olderf(const char *f1, const char *f2)
+{
+ struct stat b1, b2;
+
+ return (stat(f1, &b1) == 0 &&
+ stat(f2, &b2) == 0 &&
+ b1.st_mtime < b2.st_mtime);
+}
+
+static int
+equalf(const char *f1, const char *f2)
+{
+ struct stat b1, b2;
+
+ return (stat(f1, &b1) == 0 &&
+ stat(f2, &b2) == 0 &&
+ b1.st_dev == b2.st_dev &&
+ b1.st_ino == b2.st_ino);
+}