Index: /trunk/src/kmk/kmkbuiltin/test.c
===================================================================
--- /trunk/src/kmk/kmkbuiltin/test.c	(revision 1291)
+++ /trunk/src/kmk/kmkbuiltin/test.c	(revision 1291)
@@ -0,0 +1,716 @@
+/* $NetBSD: test.c,v 1.33 2007/06/24 18:54:58 christos 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 1.33 2007/06/24 18:54:58 christos Exp $");
+#endif
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <limits.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;
+
+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 int 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 *, ...) __attribute__((__noreturn__));
+extern void *ckmalloc(size_t);
+#else
+static void error(const char *, ...) __attribute__((__noreturn__));
+
+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]);
+	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(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 int
+getn(const char *s)
+{
+	char *p;
+	long r;
+
+	errno = 0;
+	r = strtol(s, &p, 10);
+
+	if (errno != 0)
+	      error("%s: out of range", s);
+
+	while (isspace((unsigned char)*p))
+	      p++;
+	
+	if (*p)
+	      error("%s: bad number", s);
+
+	return (int) 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);
+}
