freebsd-dev/contrib/tcsh/sh.parse.c
2007-03-11 22:33:41 +00:00

691 lines
13 KiB
C

/* $Header: /p/tcsh/cvsroot/tcsh/sh.parse.c,v 3.18 2006/03/02 18:46:44 christos Exp $ */
/*
* sh.parse.c: Interpret a list of tokens
*/
/*-
* 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. 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.
*/
#include "sh.h"
RCSID("$tcsh: sh.parse.c,v 3.18 2006/03/02 18:46:44 christos Exp $")
/*
* C shell
*/
static int asyntax (struct wordent *, struct wordent *);
static int asyn0 (struct wordent *, struct wordent *);
static int asyn3 (struct wordent *, struct wordent *);
static struct wordent *freenod (struct wordent *, struct wordent *);
static struct command *syn0 (const struct wordent *, const struct wordent *, int);
static struct command *syn1 (const struct wordent *, const struct wordent *, int);
static struct command *syn1a (const struct wordent *, const struct wordent *, int);
static struct command *syn1b (const struct wordent *, const struct wordent *, int);
static struct command *syn2 (const struct wordent *, const struct wordent *, int);
static struct command *syn3 (const struct wordent *, const struct wordent *, int);
#define ALEFT 51 /* max of 50 alias expansions */
#define HLEFT 11 /* max of 10 history expansions */
/*
* Perform aliasing on the word list lexp
* Do a (very rudimentary) parse to separate into commands.
* If word 0 of a command has an alias, do it.
* Repeat a maximum of 50 times.
*/
extern int hleft;
void
alias(struct wordent *lexp)
{
int aleft;
aleft = ALEFT;
hleft = HLEFT;
do {
if (--aleft == 0)
stderror(ERR_ALIASLOOP);
} while (asyntax(lexp->next, lexp) != 0);
}
static int
asyntax(struct wordent *p1, struct wordent *p2)
{
while (p1 != p2) {
if (!any(";&\n", p1->word[0]))
return asyn0(p1, p2);
p1 = p1->next;
}
return 0;
}
static int
asyn0(struct wordent *p1, struct wordent *p2)
{
struct wordent *p;
int l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
if (l < 0)
stderror(ERR_TOOMANYRP);
continue;
case '>':
if (p->next != p2 && eq(p->next->word, STRand))
p = p->next;
continue;
case '&':
case '|':
case ';':
case '\n':
if (l != 0)
continue;
if (asyn3(p1, p) != 0)
return 1;
return asyntax(p->next, p2);
default:
break;
}
if (l == 0)
return asyn3(p1, p2);
return 0;
}
static void
alvec_cleanup(void *dummy)
{
USE(dummy);
alhistp = NULL;
alhistt = NULL;
alvec = NULL;
}
static int
asyn3(struct wordent *p1, struct wordent *p2)
{
struct varent *ap;
struct wordent alout;
int redid;
if (p1 == p2)
return 0;
if (p1->word[0] == '(') {
for (p2 = p2->prev; p2->word[0] != ')'; p2 = p2->prev)
if (p2 == p1)
return 0;
if (p2 == p1->next)
return 0;
return asyn0(p1->next, p2);
}
ap = adrof1(p1->word, &aliases);
if (ap == 0)
return 0;
alhistp = p1->prev;
alhistt = p2;
alvec = ap->vec;
cleanup_push(&alvec, alvec_cleanup);
redid = lex(&alout);
cleanup_until(&alvec);
if (seterr) {
freelex(&alout);
stderror(ERR_OLD);
}
if (p1->word[0] && eq(p1->word, alout.next->word)) {
Char *cp = alout.next->word;
alout.next->word = Strspl(STRQNULL, cp);
xfree(cp);
}
p1 = freenod(p1, redid ? p2 : p1->next);
if (alout.next != &alout) {
p1->next->prev = alout.prev->prev;
alout.prev->prev->next = p1->next;
alout.next->prev = p1;
p1->next = alout.next;
xfree(alout.prev->word);
xfree(alout.prev);
}
return 1;
}
static struct wordent *
freenod(struct wordent *p1, struct wordent *p2)
{
struct wordent *retp = p1->prev;
while (p1 != p2) {
xfree(p1->word);
p1 = p1->next;
xfree(p1->prev);
}
retp->next = p2;
p2->prev = retp;
return (retp);
}
#define P_HERE 1
#define P_IN 2
#define P_OUT 4
#define P_DIAG 8
/*
* syntax
* empty
* syn0
*/
struct command *
syntax(const struct wordent *p1, const struct wordent *p2, int flags)
{
while (p1 != p2)
if (any(";&\n", p1->word[0]))
p1 = p1->next;
else
return (syn0(p1, p2, flags));
return (0);
}
/*
* syn0
* syn1
* syn1 & syntax
*/
static struct command *
syn0(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p;
struct command *t, *t1;
int l;
l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
if (l < 0)
seterror(ERR_TOOMANYRP);
continue;
case '|':
if (p->word[1] == '|')
continue;
/*FALLTHROUGH*/
case '>':
if (p->next != p2 && eq(p->next->word, STRand))
p = p->next;
continue;
case '&':
if (l != 0)
break;
if (p->word[1] == '&')
continue;
t1 = syn1(p1, p, flags);
if (t1->t_dtyp == NODE_LIST ||
t1->t_dtyp == NODE_AND ||
t1->t_dtyp == NODE_OR) {
t = xcalloc(1, sizeof(*t));
t->t_dtyp = NODE_PAREN;
t->t_dflg = F_AMPERSAND | F_NOINTERRUPT;
t->t_dspr = t1;
t1 = t;
}
else
t1->t_dflg |= F_AMPERSAND | F_NOINTERRUPT;
t = xcalloc(1, sizeof(*t));
t->t_dtyp = NODE_LIST;
t->t_dflg = 0;
t->t_dcar = t1;
t->t_dcdr = syntax(p, p2, flags);
return (t);
default:
break;
}
if (l == 0)
return (syn1(p1, p2, flags));
seterror(ERR_TOOMANYLP);
return (0);
}
/*
* syn1
* syn1a
* syn1a ; syntax
*/
static struct command *
syn1(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p;
struct command *t;
int l;
l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
continue;
case ';':
case '\n':
if (l != 0)
break;
t = xcalloc(1, sizeof(*t));
t->t_dtyp = NODE_LIST;
t->t_dcar = syn1a(p1, p, flags);
t->t_dcdr = syntax(p->next, p2, flags);
if (t->t_dcdr == 0)
t->t_dcdr = t->t_dcar, t->t_dcar = 0;
return (t);
default:
break;
}
return (syn1a(p1, p2, flags));
}
/*
* syn1a
* syn1b
* syn1b || syn1a
*/
static struct command *
syn1a(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p;
struct command *t;
int l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
continue;
case '|':
if (p->word[1] != '|')
continue;
if (l == 0) {
t = xcalloc(1, sizeof(*t));
t->t_dtyp = NODE_OR;
t->t_dcar = syn1b(p1, p, flags);
t->t_dcdr = syn1a(p->next, p2, flags);
t->t_dflg = 0;
return (t);
}
continue;
default:
break;
}
return (syn1b(p1, p2, flags));
}
/*
* syn1b
* syn2
* syn2 && syn1b
*/
static struct command *
syn1b(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p;
struct command *t;
int l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
continue;
case '&':
if (p->word[1] == '&' && l == 0) {
t = xcalloc(1, sizeof(*t));
t->t_dtyp = NODE_AND;
t->t_dcar = syn2(p1, p, flags);
t->t_dcdr = syn1b(p->next, p2, flags);
t->t_dflg = 0;
return (t);
}
continue;
default:
break;
}
return (syn2(p1, p2, flags));
}
/*
* syn2
* syn3
* syn3 | syn2
* syn3 |& syn2
*/
static struct command *
syn2(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p, *pn;
struct command *t;
int l = 0;
int f;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
l++;
continue;
case ')':
l--;
continue;
case '|':
if (l != 0)
continue;
t = xcalloc(1, sizeof(*t));
f = flags | P_OUT;
pn = p->next;
if (pn != p2 && pn->word[0] == '&') {
f |= P_DIAG;
t->t_dflg |= F_STDERR;
}
t->t_dtyp = NODE_PIPE;
t->t_dcar = syn3(p1, p, f);
if (pn != p2 && pn->word[0] == '&')
p = pn;
t->t_dcdr = syn2(p->next, p2, flags | P_IN);
return (t);
default:
break;
}
return (syn3(p1, p2, flags));
}
static const char RELPAR[] = {'<', '>', '(', ')', '\0'};
/*
* syn3
* ( syn0 ) [ < in ] [ > out ]
* word word* [ < in ] [ > out ]
* KEYWORD ( word* ) word* [ < in ] [ > out ]
*
* KEYWORD = (@ exit foreach if set switch test while)
*/
static struct command *
syn3(const struct wordent *p1, const struct wordent *p2, int flags)
{
const struct wordent *p;
const struct wordent *lp, *rp;
struct command *t;
int l;
Char **av;
int n, c;
int specp = 0;
if (p1 != p2) {
p = p1;
again:
switch (srchx(p->word)) {
case TC_ELSE:
p = p->next;
if (p != p2)
goto again;
break;
case TC_EXIT:
case TC_FOREACH:
case TC_IF:
case TC_LET:
case TC_SET:
case TC_SWITCH:
case TC_WHILE:
specp = 1;
break;
default:
break;
}
}
n = 0;
l = 0;
for (p = p1; p != p2; p = p->next)
switch (p->word[0]) {
case '(':
if (specp)
n++;
l++;
continue;
case ')':
if (specp)
n++;
l--;
continue;
case '>':
case '<':
if (l != 0) {
if (specp)
n++;
continue;
}
if (p->next == p2)
continue;
if (any(RELPAR, p->next->word[0]))
continue;
n--;
continue;
default:
if (!specp && l != 0)
continue;
n++;
continue;
}
if (n < 0)
n = 0;
t = xcalloc(1, sizeof(*t));
av = xcalloc(n + 1, sizeof(Char **));
t->t_dcom = av;
n = 0;
if (p2->word[0] == ')')
t->t_dflg = F_NOFORK;
lp = 0;
rp = 0;
l = 0;
for (p = p1; p != p2; p = p->next) {
c = p->word[0];
switch (c) {
case '(':
if (l == 0) {
if (lp != 0 && !specp)
seterror(ERR_BADPLP);
lp = p->next;
}
l++;
goto savep;
case ')':
l--;
if (l == 0)
rp = p;
goto savep;
case '>':
if (l != 0)
goto savep;
if (p->word[1] == '>')
t->t_dflg |= F_APPEND;
if (p->next != p2 && eq(p->next->word, STRand)) {
t->t_dflg |= F_STDERR, p = p->next;
if (flags & (P_OUT | P_DIAG)) {
seterror(ERR_OUTRED);
continue;
}
}
if (p->next != p2 && eq(p->next->word, STRbang))
t->t_dflg |= F_OVERWRITE, p = p->next;
if (p->next == p2) {
seterror(ERR_MISRED);
continue;
}
p = p->next;
if (any(RELPAR, p->word[0])) {
seterror(ERR_MISRED);
continue;
}
if (((flags & P_OUT) && (flags & P_DIAG) == 0) || t->t_drit)
seterror(ERR_OUTRED);
else
t->t_drit = Strsave(p->word);
continue;
case '<':
if (l != 0)
goto savep;
if (p->word[1] == '<')
t->t_dflg |= F_READ;
if (p->next == p2) {
seterror(ERR_MISRED);
continue;
}
p = p->next;
if (any(RELPAR, p->word[0])) {
seterror(ERR_MISRED);
continue;
}
if ((flags & P_HERE) && (t->t_dflg & F_READ))
seterror(ERR_REDPAR);
else if ((flags & P_IN) || t->t_dlef)
seterror(ERR_INRED);
else
t->t_dlef = Strsave(p->word);
continue;
savep:
if (!specp)
continue;
default:
if (l != 0 && !specp)
continue;
if (seterr == 0)
av[n] = Strsave(p->word);
n++;
continue;
}
}
if (lp != 0 && !specp) {
if (n != 0)
seterror(ERR_BADPLPS);
t->t_dtyp = NODE_PAREN;
t->t_dspr = syn0(lp, rp, P_HERE);
}
else {
if (n == 0)
seterror(ERR_NULLCOM);
t->t_dtyp = NODE_COMMAND;
}
return (t);
}
void
freesyn(struct command *t)
{
Char **v;
if (t == 0)
return;
switch (t->t_dtyp) {
case NODE_COMMAND:
for (v = t->t_dcom; *v; v++)
xfree(*v);
xfree(t->t_dcom);
xfree(t->t_dlef);
xfree(t->t_drit);
break;
case NODE_PAREN:
freesyn(t->t_dspr);
xfree(t->t_dlef);
xfree(t->t_drit);
break;
case NODE_AND:
case NODE_OR:
case NODE_PIPE:
case NODE_LIST:
freesyn(t->t_dcar), freesyn(t->t_dcdr);
break;
default:
break;
}
xfree(t);
}
void
syntax_cleanup(void *xt)
{
struct command *t;
t = xt;
freesyn(t);
}