[unix-history] / bin / csh / exp.c

/*-
 * Copyright (c) 1980, 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 */

#ifndef lint
static char sccsid[] = "@(#)exp.c	5.11 (Berkeley) 6/8/91";
#endif /* not lint */

#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#if __STDC__
# include <stdarg.h>
#else
# include <varargs.h>
#endif

#include "csh.h"
#include "extern.h"

#define IGNORE	1	/* in ignore, it means to ignore value, just parse */
#define NOGLOB	2	/* in ignore, it means not to globone */

#define	ADDOP	1
#define	MULOP	2
#define	EQOP	4
#define	RELOP	8
#define	RESTOP	16
#define	ANYOP	31

#define	EQEQ	1
#define	GTR	2
#define	LSS	4
#define	NOTEQ	6
#define EQMATCH 7
#define NOTEQMATCH 8

static int	exp1	__P((Char ***, bool));
static int	exp2	__P((Char ***, bool));
static int	exp2a	__P((Char ***, bool));
static int	exp2b	__P((Char ***, bool));
static int	exp2c	__P((Char ***, bool));
static Char *	exp3	__P((Char ***, bool));
static Char *	exp3a	__P((Char ***, bool));
static Char *	exp4	__P((Char ***, bool));
static Char *	exp5	__P((Char ***, bool));
static Char *	exp6	__P((Char ***, bool));
static void	evalav	__P((Char **));
static int	isa	__P((Char *, int));
static int	egetn	__P((Char *));

#ifdef EDEBUG
static void	etracc	__P((char *, Char *, Char ***));
static void	etraci	__P((char *, int, Char ***));
#endif

int
exp(vp)
    register Char ***vp;
{
    return (exp0(vp, 0));
}

int
exp0(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register int p1 = exp1(vp, ignore);

#ifdef EDEBUG
    etraci("exp0 p1", p1, vp);
#endif
    if (**vp && eq(**vp, STRor2)) {
	register int p2;

	(*vp)++;
	p2 = exp0(vp, (ignore & IGNORE) || p1);
#ifdef EDEBUG
	etraci("exp0 p2", p2, vp);
#endif
	return (p1 || p2);
    }
    return (p1);
}

static int
exp1(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register int p1 = exp2(vp, ignore);

#ifdef EDEBUG
    etraci("exp1 p1", p1, vp);
#endif
    if (**vp && eq(**vp, STRand2)) {
	register int p2;

	(*vp)++;
	p2 = exp1(vp, (ignore & IGNORE) || !p1);
#ifdef EDEBUG
	etraci("exp1 p2", p2, vp);
#endif
	return (p1 && p2);
    }
    return (p1);
}

static int
exp2(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register int p1 = exp2a(vp, ignore);

#ifdef EDEBUG
    etraci("exp3 p1", p1, vp);
#endif
    if (**vp && eq(**vp, STRor)) {
	register int p2;

	(*vp)++;
	p2 = exp2(vp, ignore);
#ifdef EDEBUG
	etraci("exp3 p2", p2, vp);
#endif
	return (p1 | p2);
    }
    return (p1);
}

static int
exp2a(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register int p1 = exp2b(vp, ignore);

#ifdef EDEBUG
    etraci("exp2a p1", p1, vp);
#endif
    if (**vp && eq(**vp, STRcaret)) {
	register int p2;

	(*vp)++;
	p2 = exp2a(vp, ignore);
#ifdef EDEBUG
	etraci("exp2a p2", p2, vp);
#endif
	return (p1 ^ p2);
    }
    return (p1);
}

static int
exp2b(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register int p1 = exp2c(vp, ignore);

#ifdef EDEBUG
    etraci("exp2b p1", p1, vp);
#endif
    if (**vp && eq(**vp, STRand)) {
	register int p2;

	(*vp)++;
	p2 = exp2b(vp, ignore);
#ifdef EDEBUG
	etraci("exp2b p2", p2, vp);
#endif
	return (p1 & p2);
    }
    return (p1);
}

static int
exp2c(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register Char *p1 = exp3(vp, ignore);
    register Char *p2;
    register int i;

#ifdef EDEBUG
    etracc("exp2c p1", p1, vp);
#endif
    if (i = isa(**vp, EQOP)) {
	(*vp)++;
	if (i == EQMATCH || i == NOTEQMATCH)
	    ignore |= NOGLOB;
	p2 = exp3(vp, ignore);
#ifdef EDEBUG
	etracc("exp2c p2", p2, vp);
#endif
	if (!(ignore & IGNORE))
	    switch (i) {

	    case EQEQ:
		i = eq(p1, p2);
		break;

	    case NOTEQ:
		i = !eq(p1, p2);
		break;

	    case EQMATCH:
		i = Gmatch(p1, p2);
		break;

	    case NOTEQMATCH:
		i = !Gmatch(p1, p2);
		break;
	    }
	xfree((ptr_t) p1);
	xfree((ptr_t) p2);
	return (i);
    }
    i = egetn(p1);
    xfree((ptr_t) p1);
    return (i);
}

static Char *
exp3(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register Char *p1, *p2;
    register int i;

    p1 = exp3a(vp, ignore);
#ifdef EDEBUG
    etracc("exp3 p1", p1, vp);
#endif
    if (i = isa(**vp, RELOP)) {
	(*vp)++;
	if (**vp && eq(**vp, STRequal))
	    i |= 1, (*vp)++;
	p2 = exp3(vp, ignore);
#ifdef EDEBUG
	etracc("exp3 p2", p2, vp);
#endif
	if (!(ignore & IGNORE))
	    switch (i) {

	    case GTR:
		i = egetn(p1) > egetn(p2);
		break;

	    case GTR | 1:
		i = egetn(p1) >= egetn(p2);
		break;

	    case LSS:
		i = egetn(p1) < egetn(p2);
		break;

	    case LSS | 1:
		i = egetn(p1) <= egetn(p2);
		break;
	    }
	xfree((ptr_t) p1);
	xfree((ptr_t) p2);
	return (putn(i));
    }
    return (p1);
}

static Char *
exp3a(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register Char *p1, *p2, *op;
    register int i;

    p1 = exp4(vp, ignore);
#ifdef EDEBUG
    etracc("exp3a p1", p1, vp);
#endif
    op = **vp;
    if (op && any("<>", op[0]) && op[0] == op[1]) {
	(*vp)++;
	p2 = exp3a(vp, ignore);
#ifdef EDEBUG
	etracc("exp3a p2", p2, vp);
#endif
	if (op[0] == '<')
	    i = egetn(p1) << egetn(p2);
	else
	    i = egetn(p1) >> egetn(p2);
	xfree((ptr_t) p1);
	xfree((ptr_t) p2);
	return (putn(i));
    }
    return (p1);
}

static Char *
exp4(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register Char *p1, *p2;
    register int i = 0;

    p1 = exp5(vp, ignore);
#ifdef EDEBUG
    etracc("exp4 p1", p1, vp);
#endif
    if (isa(**vp, ADDOP)) {
	register Char *op = *(*vp)++;

	p2 = exp4(vp, ignore);
#ifdef EDEBUG
	etracc("exp4 p2", p2, vp);
#endif
	if (!(ignore & IGNORE))
	    switch (op[0]) {

	    case '+':
		i = egetn(p1) + egetn(p2);
		break;

	    case '-':
		i = egetn(p1) - egetn(p2);
		break;
	    }
	xfree((ptr_t) p1);
	xfree((ptr_t) p2);
	return (putn(i));
    }
    return (p1);
}

static Char *
exp5(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    register Char *p1, *p2;
    register int i = 0;

    p1 = exp6(vp, ignore);
#ifdef EDEBUG
    etracc("exp5 p1", p1, vp);
#endif
    if (isa(**vp, MULOP)) {
	register Char *op = *(*vp)++;

	p2 = exp5(vp, ignore);
#ifdef EDEBUG
	etracc("exp5 p2", p2, vp);
#endif
	if (!(ignore & IGNORE))
	    switch (op[0]) {

	    case '*':
		i = egetn(p1) * egetn(p2);
		break;

	    case '/':
		i = egetn(p2);
		if (i == 0)
		    stderror(ERR_DIV0);
		i = egetn(p1) / i;
		break;

	    case '%':
		i = egetn(p2);
		if (i == 0)
		    stderror(ERR_MOD0);
		i = egetn(p1) % i;
		break;
	    }
	xfree((ptr_t) p1);
	xfree((ptr_t) p2);
	return (putn(i));
    }
    return (p1);
}

static Char *
exp6(vp, ignore)
    register Char ***vp;
    bool    ignore;
{
    int     ccode, i = 0;
    register Char *cp, *dp, *ep;

    if (**vp == 0)
	stderror(ERR_NAME | ERR_EXPRESSION);
    if (eq(**vp, STRbang)) {
	(*vp)++;
	cp = exp6(vp, ignore);
#ifdef EDEBUG
	etracc("exp6 ! cp", cp, vp);
#endif
	i = egetn(cp);
	xfree((ptr_t) cp);
	return (putn(!i));
    }
    if (eq(**vp, STRtilde)) {
	(*vp)++;
	cp = exp6(vp, ignore);
#ifdef EDEBUG
	etracc("exp6 ~ cp", cp, vp);
#endif
	i = egetn(cp);
	xfree((ptr_t) cp);
	return (putn(~i));
    }
    if (eq(**vp, STRLparen)) {
	(*vp)++;
	ccode = exp0(vp, ignore);
#ifdef EDEBUG
	etraci("exp6 () ccode", ccode, vp);
#endif
	if (*vp == 0 || **vp == 0 || ***vp != ')')
	    stderror(ERR_NAME | ERR_EXPRESSION);
	(*vp)++;
	return (putn(ccode));
    }
    if (eq(**vp, STRLbrace)) {
	register Char **v;
	struct command faket;
	Char   *fakecom[2];

	faket.t_dtyp = NODE_COMMAND;
	faket.t_dflg = 0;
	faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
	faket.t_dcom = fakecom;
	fakecom[0] = STRfakecom;
	fakecom[1] = NULL;
	(*vp)++;
	v = *vp;
	for (;;) {
	    if (!**vp)
		stderror(ERR_NAME | ERR_MISSING, '}');
	    if (eq(*(*vp)++, STRRbrace))
		break;
	}
	if (ignore & IGNORE)
	    return (Strsave(STRNULL));
	psavejob();
	if (pfork(&faket, -1) == 0) {
	    *--(*vp) = 0;
	    evalav(v);
	    exitstat();
	}
	pwait();
	prestjob();
#ifdef EDEBUG
	etraci("exp6 {} status", egetn(value(STRstatus)), vp);
#endif
	return (putn(egetn(value(STRstatus)) == 0));
    }
    if (isa(**vp, ANYOP))
	return (Strsave(STRNULL));
    cp = *(*vp)++;
    if (*cp == '-' && any("erwxfdzopls", cp[1])) {
	struct stat stb;

	if (cp[2] != '\0')
	    stderror(ERR_NAME | ERR_FILEINQ);
	/*
	 * Detect missing file names by checking for operator in the file name
	 * position.  However, if an operator name appears there, we must make
	 * sure that there's no file by that name (e.g., "/") before announcing
	 * an error.  Even this check isn't quite right, since it doesn't take
	 * globbing into account.
	 */
	if (isa(**vp, ANYOP) && stat(short2str(**vp), &stb))
	    stderror(ERR_NAME | ERR_FILENAME);

	dp = *(*vp)++;
	if (ignore & IGNORE)
	    return (Strsave(STRNULL));
	ep = globone(dp, G_ERROR);
	switch (cp[1]) {

	case 'r':
	    i = !access(short2str(ep), R_OK);
	    break;

	case 'w':
	    i = !access(short2str(ep), W_OK);
	    break;

	case 'x':
	    i = !access(short2str(ep), X_OK);
	    break;

	default:
	    if (
#ifdef S_IFLNK
		cp[1] == 'l' ? lstat(short2str(ep), &stb) :
#endif
		stat(short2str(ep), &stb)) {
		xfree((ptr_t) ep);
		return (Strsave(STR0));
	    }
	    switch (cp[1]) {

	    case 'f':
		i = S_ISREG(stb.st_mode);
		break;

	    case 'd':
		i = S_ISDIR(stb.st_mode);
		break;

	    case 'p':
#ifdef S_ISFIFO
		i = S_ISFIFO(stb.st_mode);
#else
		i = 0;
#endif
		break;

	    case 'l':
#ifdef S_ISLNK
		i = S_ISLNK(stb.st_mode);
#else
		i = 0;
#endif
		break;

	    case 's':
#ifdef S_ISSOCK
		i = S_ISSOCK(stb.st_mode);
#else
		i = 0;
#endif
		break;

	    case 'z':
		i = stb.st_size == 0;
		break;

	    case 'e':
		i = 1;
		break;

	    case 'o':
		i = stb.st_uid == uid;
		break;
	    }
	}
#ifdef EDEBUG
	etraci("exp6 -? i", i, vp);
#endif
	xfree((ptr_t) ep);
	return (putn(i));
    }
#ifdef EDEBUG
    etracc("exp6 default", cp, vp);
#endif
    return (ignore & NOGLOB ? Strsave(cp) : globone(cp, G_ERROR));
}

static void
evalav(v)
    register Char **v;
{
    struct wordent paraml1;
    register struct wordent *hp = &paraml1;
    struct command *t;
    register struct wordent *wdp = hp;

    set(STRstatus, Strsave(STR0));
    hp->prev = hp->next = hp;
    hp->word = STRNULL;
    while (*v) {
	register struct wordent *new =
	(struct wordent *) xcalloc(1, sizeof *wdp);

	new->prev = wdp;
	new->next = hp;
	wdp->next = new;
	wdp = new;
	wdp->word = Strsave(*v++);
    }
    hp->prev = wdp;
    alias(&paraml1);
    t = syntax(paraml1.next, &paraml1, 0);
    if (seterr)
	stderror(ERR_OLD);
    execute(t, -1, NULL, NULL);
    freelex(&paraml1), freesyn(t);
}

static int
isa(cp, what)
    register Char *cp;
    register int what;
{
    if (cp == 0)
	return ((what & RESTOP) != 0);
    if (cp[1] == 0) {
	if (what & ADDOP && (*cp == '+' || *cp == '-'))
	    return (1);
	if (what & MULOP && (*cp == '*' || *cp == '/' || *cp == '%'))
	    return (1);
	if (what & RESTOP && (*cp == '(' || *cp == ')' || *cp == '!' ||
			      *cp == '~' || *cp == '^' || *cp == '"'))
	    return (1);
    }
    else if (cp[2] == 0) {
	if (what & RESTOP) {
	    if (cp[0] == '|' && cp[1] == '&')
		return (1);
	    if (cp[0] == '<' && cp[1] == '<')
		return (1);
	    if (cp[0] == '>' && cp[1] == '>')
		return (1);
	}
	if (what & EQOP) {
	    if (cp[0] == '=') {
		if (cp[1] == '=')
		    return (EQEQ);
		if (cp[1] == '~')
		    return (EQMATCH);
	    }
	    else if (cp[0] == '!') {
		if (cp[1] == '=')
		    return (NOTEQ);
		if (cp[1] == '~')
		    return (NOTEQMATCH);
	    }
	}
    }
    if (what & RELOP) {
	if (*cp == '<')
	    return (LSS);
	if (*cp == '>')
	    return (GTR);
    }
    return (0);
}

static int
egetn(cp)
    register Char *cp;
{
    if (*cp && *cp != '-' && !Isdigit(*cp))
	stderror(ERR_NAME | ERR_EXPRESSION);
    return (getn(cp));
}

/* Phew! */

#ifdef EDEBUG
static void
etraci(str, i, vp)
    char   *str;
    int     i;
    Char ***vp;
{
    xprintf("%s=%d\t", str, i);
    blkpr(*vp);
    xprintf("\n");
}
static void
etracc(str, cp, vp)
    char   *str;
    Char   *cp;
    Char ***vp;
{
    xprintf("%s=%s\t", str, cp);
    blkpr(*vp);
    xprintf("\n");
}
#endif
Commit	Line	Data
15637ed4 RG	1	/*-
	2	* Copyright (c) 1980, 1991 The Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*/
	33
	34	#ifndef lint
	35	static char sccsid[] = "@(#)exp.c 5.11 (Berkeley) 6/8/91";
	36	#endif /* not lint */
	37
	38	#include <sys/types.h>
	39	#include <sys/stat.h>
	40	#include <stdlib.h>
	41	#include <unistd.h>
	42	#if __STDC__
	43	# include <stdarg.h>
	44	#else
	45	# include <varargs.h>
	46	#endif
	47
	48	#include "csh.h"
	49	#include "extern.h"
	50
	51	#define IGNORE 1 /* in ignore, it means to ignore value, just parse */
	52	#define NOGLOB 2 /* in ignore, it means not to globone */
	53
	54	#define ADDOP 1
	55	#define MULOP 2
	56	#define EQOP 4
	57	#define RELOP 8
	58	#define RESTOP 16
	59	#define ANYOP 31
	60
	61	#define EQEQ 1
	62	#define GTR 2
	63	#define LSS 4
	64	#define NOTEQ 6
65	#define EQMATCH 7
66	#define NOTEQMATCH 8
67
68	static int exp1 __P((Char ***, bool));
69	static int exp2 __P((Char ***, bool));
70	static int exp2a __P((Char ***, bool));
71	static int exp2b __P((Char ***, bool));
72	static int exp2c __P((Char ***, bool));
73	static Char * exp3 __P((Char ***, bool));
74	static Char * exp3a __P((Char ***, bool));
75	static Char * exp4 __P((Char ***, bool));
76	static Char * exp5 __P((Char ***, bool));
77	static Char * exp6 __P((Char ***, bool));
78	static void evalav __P((Char **));
79	static int isa __P((Char *, int));
80	static int egetn __P((Char *));
81
82	#ifdef EDEBUG
83	static void etracc __P((char , Char , Char ***));
84	static void etraci __P((char , int, Char **));
85	#endif
86
87	int
88	exp(vp)
89	register Char ***vp;
90	{
91	return (exp0(vp, 0));
92	}
93
94	int
95	exp0(vp, ignore)
96	register Char ***vp;
97	bool ignore;
98	{
99	register int p1 = exp1(vp, ignore);
100
101	#ifdef EDEBUG
102	etraci("exp0 p1", p1, vp);
103	#endif
104	if (vp && eq(vp, STRor2)) {
105	register int p2;
106
107	(*vp)++;
108	p2 = exp0(vp, (ignore & IGNORE) \|\| p1);
109	#ifdef EDEBUG
110	etraci("exp0 p2", p2, vp);
111	#endif
112	return (p1 \|\| p2);
113	}
114	return (p1);
115	}
116
117	static int
118	exp1(vp, ignore)
119	register Char ***vp;
120	bool ignore;
121	{
122	register int p1 = exp2(vp, ignore);
123
124	#ifdef EDEBUG
125	etraci("exp1 p1", p1, vp);
126	#endif
127	if (vp && eq(vp, STRand2)) {
128	register int p2;
129
130	(*vp)++;
131	p2 = exp1(vp, (ignore & IGNORE) \|\| !p1);
132	#ifdef EDEBUG
133	etraci("exp1 p2", p2, vp);
134	#endif
135	return (p1 && p2);
136	}
137	return (p1);
138	}
139
140	static int
141	exp2(vp, ignore)
142	register Char ***vp;
143	bool ignore;
144	{
145	register int p1 = exp2a(vp, ignore);
146
147	#ifdef EDEBUG
148	etraci("exp3 p1", p1, vp);
149	#endif
150	if (vp && eq(vp, STRor)) {
151	register int p2;
152
153	(*vp)++;
154	p2 = exp2(vp, ignore);
155	#ifdef EDEBUG
156	etraci("exp3 p2", p2, vp);
157	#endif
158	return (p1 \| p2);
159	}
160	return (p1);
161	}
162
163	static int
164	exp2a(vp, ignore)
165	register Char ***vp;
166	bool ignore;
167	{
168	register int p1 = exp2b(vp, ignore);
169
170	#ifdef EDEBUG
171	etraci("exp2a p1", p1, vp);
172	#endif
173	if (vp && eq(vp, STRcaret)) {
174	register int p2;
175
176	(*vp)++;
177	p2 = exp2a(vp, ignore);
178	#ifdef EDEBUG
179	etraci("exp2a p2", p2, vp);
180	#endif
181	return (p1 ^ p2);
182	}
183	return (p1);
184	}
185
186	static int
187	exp2b(vp, ignore)
188	register Char ***vp;
189	bool ignore;
190	{
191	register int p1 = exp2c(vp, ignore);
192
193	#ifdef EDEBUG
194	etraci("exp2b p1", p1, vp);
195	#endif
196	if (vp && eq(vp, STRand)) {
197	register int p2;
198
199	(*vp)++;
200	p2 = exp2b(vp, ignore);
201	#ifdef EDEBUG
202	etraci("exp2b p2", p2, vp);
203	#endif
204	return (p1 & p2);
205	}
206	return (p1);
207	}
208
209	static int
210	exp2c(vp, ignore)
211	register Char ***vp;
212	bool ignore;
213	{
214	register Char *p1 = exp3(vp, ignore);
215	register Char *p2;
216	register int i;
217
218	#ifdef EDEBUG
219	etracc("exp2c p1", p1, vp);
220	#endif
221	if (i = isa(**vp, EQOP)) {
222	(*vp)++;
223	if (i == EQMATCH \|\| i == NOTEQMATCH)
224	ignore \|= NOGLOB;
225	p2 = exp3(vp, ignore);
226	#ifdef EDEBUG
227	etracc("exp2c p2", p2, vp);
228	#endif
229	if (!(ignore & IGNORE))
230	switch (i) {
231
232	case EQEQ:
233	i = eq(p1, p2);
234	break;
235
236	case NOTEQ:
237	i = !eq(p1, p2);
238	break;
239
240	case EQMATCH:
241	i = Gmatch(p1, p2);
242	break;
243
244	case NOTEQMATCH:
245	i = !Gmatch(p1, p2);
246	break;
247	}
248	xfree((ptr_t) p1);
249	xfree((ptr_t) p2);
250	return (i);
251	}
252	i = egetn(p1);
253	xfree((ptr_t) p1);
254	return (i);
255	}
256
257	static Char *
258	exp3(vp, ignore)
259	register Char ***vp;
260	bool ignore;
261	{
262	register Char p1, p2;
263	register int i;
264
265	p1 = exp3a(vp, ignore);
266	#ifdef EDEBUG
267	etracc("exp3 p1", p1, vp);
268	#endif
269	if (i = isa(**vp, RELOP)) {
270	(*vp)++;
271	if (vp && eq(vp, STRequal))
272	i \|= 1, (*vp)++;
273	p2 = exp3(vp, ignore);
274	#ifdef EDEBUG
275	etracc("exp3 p2", p2, vp);
276	#endif
277	if (!(ignore & IGNORE))
278	switch (i) {
279
280	case GTR:
281	i = egetn(p1) > egetn(p2);
282	break;
283
284	case GTR \| 1:
285	i = egetn(p1) >= egetn(p2);
286	break;
287
288	case LSS:
289	i = egetn(p1) < egetn(p2);
290	break;
291
292	case LSS \| 1:
293	i = egetn(p1) <= egetn(p2);
294	break;
295	}
296	xfree((ptr_t) p1);
297	xfree((ptr_t) p2);
298	return (putn(i));
299	}
300	return (p1);
301	}
302
303	static Char *
304	exp3a(vp, ignore)
305	register Char ***vp;
306	bool ignore;
307	{
308	register Char p1, p2, *op;
309	register int i;
310
311	p1 = exp4(vp, ignore);
312	#ifdef EDEBUG
313	etracc("exp3a p1", p1, vp);
314	#endif
315	op = **vp;
316	if (op && any("<>", op[0]) && op[0] == op[1]) {
317	(*vp)++;
318	p2 = exp3a(vp, ignore);
319	#ifdef EDEBUG
320	etracc("exp3a p2", p2, vp);
321	#endif
322	if (op[0] == '<')
323	i = egetn(p1) << egetn(p2);
324	else
325	i = egetn(p1) >> egetn(p2);
326	xfree((ptr_t) p1);
327	xfree((ptr_t) p2);
328	return (putn(i));
329	}
330	return (p1);
331	}
332
333	static Char *
334	exp4(vp, ignore)
335	register Char ***vp;
336	bool ignore;
337	{
338	register Char p1, p2;
339	register int i = 0;
340
341	p1 = exp5(vp, ignore);
342	#ifdef EDEBUG
343	etracc("exp4 p1", p1, vp);
344	#endif
345	if (isa(**vp, ADDOP)) {
346	register Char op = (*vp)++;
347
348	p2 = exp4(vp, ignore);
349	#ifdef EDEBUG
350	etracc("exp4 p2", p2, vp);
351	#endif
352	if (!(ignore & IGNORE))
353	switch (op[0]) {
354
355	case '+':
356	i = egetn(p1) + egetn(p2);
357	break;
358
359	case '-':
360	i = egetn(p1) - egetn(p2);
361	break;
362	}
363	xfree((ptr_t) p1);
364	xfree((ptr_t) p2);
365	return (putn(i));
366	}
367	return (p1);
368	}
369
370	static Char *
371	exp5(vp, ignore)
372	register Char ***vp;
373	bool ignore;
374	{
375	register Char p1, p2;
376	register int i = 0;
377
378	p1 = exp6(vp, ignore);
379	#ifdef EDEBUG
380	etracc("exp5 p1", p1, vp);
381	#endif
382	if (isa(**vp, MULOP)) {
383	register Char op = (*vp)++;
384
385	p2 = exp5(vp, ignore);
386	#ifdef EDEBUG
387	etracc("exp5 p2", p2, vp);
388	#endif
389	if (!(ignore & IGNORE))
390	switch (op[0]) {
391
392	case '*':
393	i = egetn(p1) * egetn(p2);
394	break;
395
396	case '/':
397	i = egetn(p2);
398	if (i == 0)
399	stderror(ERR_DIV0);
400	i = egetn(p1) / i;
401	break;
402
403	case '%':
404	i = egetn(p2);
405	if (i == 0)
406	stderror(ERR_MOD0);
407	i = egetn(p1) % i;
408	break;
409	}
410	xfree((ptr_t) p1);
411	xfree((ptr_t) p2);
412	return (putn(i));
413	}
414	return (p1);
415	}
416
417	static Char *
418	exp6(vp, ignore)
419	register Char ***vp;
420	bool ignore;
421	{
422	int ccode, i = 0;
423	register Char cp, dp, *ep;
424
425	if (**vp == 0)
426	stderror(ERR_NAME \| ERR_EXPRESSION);
427	if (eq(**vp, STRbang)) {
428	(*vp)++;
429	cp = exp6(vp, ignore);
430	#ifdef EDEBUG
431	etracc("exp6 ! cp", cp, vp);
432	#endif
433	i = egetn(cp);
434	xfree((ptr_t) cp);
435	return (putn(!i));
436	}
437	if (eq(**vp, STRtilde)) {
438	(*vp)++;
439	cp = exp6(vp, ignore);
440	#ifdef EDEBUG
441	etracc("exp6 ~ cp", cp, vp);
442	#endif
443	i = egetn(cp);
444	xfree((ptr_t) cp);
445	return (putn(~i));
446	}
447	if (eq(**vp, STRLparen)) {
448	(*vp)++;
449	ccode = exp0(vp, ignore);
450	#ifdef EDEBUG
451	etraci("exp6 () ccode", ccode, vp);
452	#endif
453	if (vp == 0 \|\| vp == 0 \|\| **vp != ')')
454	stderror(ERR_NAME \| ERR_EXPRESSION);
455	(*vp)++;
456	return (putn(ccode));
457	}
458	if (eq(**vp, STRLbrace)) {
459	register Char **v;
460	struct command faket;
461	Char *fakecom[2];
462
463	faket.t_dtyp = NODE_COMMAND;
464	faket.t_dflg = 0;
465	faket.t_dcar = faket.t_dcdr = faket.t_dspr = NULL;
466	faket.t_dcom = fakecom;
467	fakecom[0] = STRfakecom;
468	fakecom[1] = NULL;
469	(*vp)++;
470	v = *vp;
471	for (;;) {
472	if (!**vp)
473	stderror(ERR_NAME \| ERR_MISSING, '}');
474	if (eq((vp)++, STRRbrace))
475	break;
476	}
477	if (ignore & IGNORE)
478	return (Strsave(STRNULL));
479	psavejob();
480	if (pfork(&faket, -1) == 0) {
481	--(vp) = 0;
482	evalav(v);
483	exitstat();
484	}
485	pwait();
486	prestjob();
487	#ifdef EDEBUG
488	etraci("exp6 {} status", egetn(value(STRstatus)), vp);
489	#endif
490	return (putn(egetn(value(STRstatus)) == 0));
491	}
492	if (isa(**vp, ANYOP))
493	return (Strsave(STRNULL));
494	cp = (vp)++;
495	if (*cp == '-' && any("erwxfdzopls", cp[1])) {
496	struct stat stb;
497
498	if (cp[2] != '\0')
499	stderror(ERR_NAME \| ERR_FILEINQ);
500	/*
501	* Detect missing file names by checking for operator in the file name
502	* position. However, if an operator name appears there, we must make
503	* sure that there's no file by that name (e.g., "/") before announcing
504	* an error. Even this check isn't quite right, since it doesn't take
505	* globbing into account.
506	*/
507	if (isa(vp, ANYOP) && stat(short2str(vp), &stb))
508	stderror(ERR_NAME \| ERR_FILENAME);
509
510	dp = (vp)++;
511	if (ignore & IGNORE)
512	return (Strsave(STRNULL));
513	ep = globone(dp, G_ERROR);
514	switch (cp[1]) {
515
516	case 'r':
517	i = !access(short2str(ep), R_OK);
518	break;
519
520	case 'w':
521	i = !access(short2str(ep), W_OK);
522	break;
523
524	case 'x':
525	i = !access(short2str(ep), X_OK);
526	break;
527
528	default:
529	if (
530	#ifdef S_IFLNK
531	cp[1] == 'l' ? lstat(short2str(ep), &stb) :
532	#endif
533	stat(short2str(ep), &stb)) {
534	xfree((ptr_t) ep);
535	return (Strsave(STR0));
536	}
537	switch (cp[1]) {
538
539	case 'f':
540	i = S_ISREG(stb.st_mode);
541	break;
542
543	case 'd':
544	i = S_ISDIR(stb.st_mode);
545	break;
546
547	case 'p':
548	#ifdef S_ISFIFO
549	i = S_ISFIFO(stb.st_mode);
550	#else
551	i = 0;
552	#endif
553	break;
554
555	case 'l':
556	#ifdef S_ISLNK
557	i = S_ISLNK(stb.st_mode);
558	#else
559	i = 0;
560	#endif
561	break;
562
563	case 's':
564	#ifdef S_ISSOCK
565	i = S_ISSOCK(stb.st_mode);
566	#else
567	i = 0;
568	#endif
569	break;
570
571	case 'z':
572	i = stb.st_size == 0;
573	break;
574
575	case 'e':
576	i = 1;
577	break;
578
579	case 'o':
580	i = stb.st_uid == uid;
581	break;
582	}
583	}
584	#ifdef EDEBUG
585	etraci("exp6 -? i", i, vp);
586	#endif
587	xfree((ptr_t) ep);
588	return (putn(i));
589	}
590	#ifdef EDEBUG
591	etracc("exp6 default", cp, vp);
592	#endif
593	return (ignore & NOGLOB ? Strsave(cp) : globone(cp, G_ERROR));
594	}
595
596	static void
597	evalav(v)
598	register Char **v;
599	{
600	struct wordent paraml1;
601	register struct wordent *hp = &paraml1;
602	struct command *t;
603	register struct wordent *wdp = hp;
604
605	set(STRstatus, Strsave(STR0));
606	hp->prev = hp->next = hp;
607	hp->word = STRNULL;
608	while (*v) {
609	register struct wordent *new =
610	(struct wordent ) xcalloc(1, sizeof wdp);
611
612	new->prev = wdp;
613	new->next = hp;
614	wdp->next = new;
615	wdp = new;
616	wdp->word = Strsave(*v++);
617	}
618	hp->prev = wdp;
619	alias(&paraml1);
620	t = syntax(paraml1.next, &paraml1, 0);
621	if (seterr)
622	stderror(ERR_OLD);
623	execute(t, -1, NULL, NULL);
624	freelex(&paraml1), freesyn(t);
625	}
626
627	static int
628	isa(cp, what)
629	register Char *cp;
630	register int what;
631	{
632	if (cp == 0)
633	return ((what & RESTOP) != 0);
634	if (cp[1] == 0) {
635	if (what & ADDOP && (cp == '+' \|\| cp == '-'))
636	return (1);
637	if (what & MULOP && (cp == '' \|\| cp == '/' \|\| cp == '%'))
638	return (1);
639	if (what & RESTOP && (cp == '(' \|\| cp == ')' \|\| *cp == '!' \|\|
640	cp == '~' \|\| cp == '^' \|\| *cp == '"'))
641	return (1);
642	}
643	else if (cp[2] == 0) {
644	if (what & RESTOP) {
645	if (cp[0] == '\|' && cp[1] == '&')
646	return (1);
647	if (cp[0] == '<' && cp[1] == '<')
648	return (1);
649	if (cp[0] == '>' && cp[1] == '>')
650	return (1);
651	}
652	if (what & EQOP) {
653	if (cp[0] == '=') {
654	if (cp[1] == '=')
655	return (EQEQ);
656	if (cp[1] == '~')
657	return (EQMATCH);
658	}
659	else if (cp[0] == '!') {
660	if (cp[1] == '=')
661	return (NOTEQ);
662	if (cp[1] == '~')
663	return (NOTEQMATCH);
664	}
665	}
666	}
667	if (what & RELOP) {
668	if (*cp == '<')
669	return (LSS);
670	if (*cp == '>')
671	return (GTR);
672	}
673	return (0);
674	}
675
676	static int
677	egetn(cp)
678	register Char *cp;
679	{
680	if (cp && cp != '-' && !Isdigit(*cp))
681	stderror(ERR_NAME \| ERR_EXPRESSION);
682	return (getn(cp));
683	}
684
685	/* Phew! */
686
687	#ifdef EDEBUG
688	static void
689	etraci(str, i, vp)
690	char *str;
691	int i;
692	Char ***vp;
693	{
694	xprintf("%s=%d\t", str, i);
695	blkpr(*vp);
696	xprintf("\n");
697	}
698	static void
699	etracc(str, cp, vp)
700	char *str;
701	Char *cp;
702	Char ***vp;
703	{
704	xprintf("%s=%s\t", str, cp);
705	blkpr(*vp);
706	xprintf("\n");
707	}
708	#endif