STATIC union node *
command(void)
{
union node *n1, *n2;
union node *ap, **app;
union node *cp, **cpp;
union node *redir, **rpp;
int t, negate = 0;
checkkwd = 2;
redir = NULL;
n1 = NULL;
rpp = &redir;
/* Check for redirection which may precede command */
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback++;
while (readtoken() == TNOT) {
TRACE(("command: TNOT recognized\n"));
negate = !negate;
}
tokpushback++;
switch (readtoken()) {
case TIF:
n1 = (union node *)stalloc(sizeof (struct nif));
n1->type = NIF;
if ((n1->nif.test = list(0)) == NULL)
synexpect(-1);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n1->nif.ifpart = list(0);
n2 = n1;
while (readtoken() == TELIF) {
n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
n2 = n2->nif.elsepart;
n2->type = NIF;
if ((n2->nif.test = list(0)) == NULL)
synexpect(-1);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n2->nif.ifpart = list(0);
}
if (lasttoken == TELSE)
n2->nif.elsepart = list(0);
else {
n2->nif.elsepart = NULL;
tokpushback++;
}
if (readtoken() != TFI)
synexpect(TFI);
checkkwd = 1;
break;
case TWHILE:
case TUNTIL: {
int got;
n1 = (union node *)stalloc(sizeof (struct nbinary));
n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
if ((n1->nbinary.ch1 = list(0)) == NULL)
synexpect(-1);
if ((got=readtoken()) != TDO) {
TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
synexpect(TDO);
}
n1->nbinary.ch2 = list(0);
if (readtoken() != TDONE)
synexpect(TDONE);
checkkwd = 1;
break;
}
case TFOR:
if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
synerror("Bad for loop variable");
n1 = (union node *)stalloc(sizeof (struct nfor));
n1->type = NFOR;
n1->nfor.var = wordtext;
if (readtoken() == TWORD && ! quoteflag && equal(wordtext, "in")) {
app = ≈
while (readtoken() == TWORD) {
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
*app = n2;
app = &n2->narg.next;
}
*app = NULL;
n1->nfor.args = ap;
if (lasttoken != TNL && lasttoken != TSEMI)
synexpect(-1);
} else {
#ifndef GDB_HACK
static const char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE,
'@', '=', '\0'};
#endif
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = (char *)argvars;
n2->narg.backquote = NULL;
n2->narg.next = NULL;
n1->nfor.args = n2;
/*
* Newline or semicolon here is optional (but note
* that the original Bourne shell only allowed NL).
*/
if (lasttoken != TNL && lasttoken != TSEMI)
tokpushback++;
}
checkkwd = 2;
if ((t = readtoken()) == TDO)
t = TDONE;
else if (t == TBEGIN)
t = TEND;
else
synexpect(-1);
n1->nfor.body = list(0);
if (readtoken() != t)
synexpect(t);
checkkwd = 1;
break;
case TCASE:
n1 = (union node *)stalloc(sizeof (struct ncase));
n1->type = NCASE;
if (readtoken() != TWORD)
synexpect(TWORD);
n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
n2->narg.next = NULL;
while (readtoken() == TNL);
if (lasttoken != TWORD || ! equal(wordtext, "in"))
synerror("expecting \"in\"");
cpp = &n1->ncase.cases;
noaliases = 1; /* turn off alias expansion */
checkkwd = 2, readtoken();
while (lasttoken != TESAC) {
*cpp = cp = (union node *)stalloc(sizeof (struct nclist));
cp->type = NCLIST;
app = &cp->nclist.pattern;
if (lasttoken == TLP)
readtoken();
for (;;) {
*app = ap = (union node *)stalloc(sizeof (struct narg));
ap->type = NARG;
ap->narg.text = wordtext;
ap->narg.backquote = backquotelist;
if (checkkwd = 2, readtoken() != TPIPE)
break;
app = &ap->narg.next;
readtoken();
}
ap->narg.next = NULL;
if (lasttoken != TRP)
noaliases = 0, synexpect(TRP);
cp->nclist.body = list(0);
checkkwd = 2;
if ((t = readtoken()) != TESAC) {
if (t != TENDCASE)
noaliases = 0, synexpect(TENDCASE);
else
checkkwd = 2, readtoken();
}
cpp = &cp->nclist.next;
}
noaliases = 0; /* reset alias expansion */
*cpp = NULL;
checkkwd = 1;
break;
case TLP:
n1 = (union node *)stalloc(sizeof (struct nredir));
n1->type = NSUBSHELL;
n1->nredir.n = list(0);
n1->nredir.redirect = NULL;
if (readtoken() != TRP)
synexpect(TRP);
checkkwd = 1;
break;
case TBEGIN:
n1 = list(0);
if (readtoken() != TEND)
synexpect(TEND);
checkkwd = 1;
break;
/* Handle an empty command like other simple commands. */
case TSEMI:
case TAND:
case TOR:
/*
* An empty command before a ; doesn't make much sense, and
* should certainly be disallowed in the case of `if ;'.
*/
if (!redir)
synexpect(-1);
case TNL:
case TEOF:
case TWORD:
case TRP:
tokpushback++;
n1 = simplecmd(rpp, redir);
goto checkneg;
default:
synexpect(-1);
}
/* Now check for redirection which may follow command */
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback++;
*rpp = NULL;
if (redir) {
if (n1->type != NSUBSHELL) {
n2 = (union node *)stalloc(sizeof (struct nredir));
n2->type = NREDIR;
n2->nredir.n = n1;
n1 = n2;
}
n1->nredir.redirect = redir;
}
checkneg:
if (negate) {
n2 = (union node *)stalloc(sizeof (struct nnot));
n2->type = NNOT;
n2->nnot.com = n1;
return n2;
}
else
return n1;
}
STATIC union node *
command() {
union node *n1, *n2;
union node *ap, **app;
union node *cp, **cpp;
union node *redir, **rpp;
int t;
checkkwd();
switch (readtoken()) {
case TIF:
n1 = (union node *)stalloc(sizeof (struct nif));
n1->type = NIF;
n1->nif.test = list(0);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n1->nif.ifpart = list(0);
n2 = n1;
while (readtoken() == TELIF) {
n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
n2 = n2->nif.elsepart;
n2->type = NIF;
n2->nif.test = list(0);
if (readtoken() != TTHEN)
synexpect(TTHEN);
n2->nif.ifpart = list(0);
}
if (lasttoken == TELSE)
n2->nif.elsepart = list(0);
else {
n2->nif.elsepart = NULL;
tokpushback++;
}
if (readtoken() != TFI)
synexpect(TFI);
break;
case TWHILE:
case TUNTIL:
n1 = (union node *)stalloc(sizeof (struct nbinary));
n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
n1->nbinary.ch1 = list(0);
if (readtoken() != TDO)
synexpect(TDO);
n1->nbinary.ch2 = list(0);
if (readtoken() != TDONE)
synexpect(TDONE);
break;
case TFOR:
if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
synerror("Bad for loop variable");
n1 = (union node *)stalloc(sizeof (struct nfor));
n1->type = NFOR;
n1->nfor.var = wordtext;
if (readtoken() == TWORD && ! quoteflag && equal(wordtext, "in")) {
app = ≈
while (readtoken() == TWORD) {
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
*app = n2;
app = &n2->narg.next;
}
*app = NULL;
n1->nfor.args = ap;
} else {
#ifndef GDB_HACK
static const char argvars[5] = {CTLVAR, VSNORMAL|VSQUOTE,
'@', '=', '\0'};
#endif
n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = (char *)argvars;
n2->narg.backquote = NULL;
n2->narg.next = NULL;
n1->nfor.args = n2;
}
if (lasttoken != TNL && lasttoken != TSEMI)
synexpect(-1);
checkkwd();
if ((t = readtoken()) == TDO)
t = TDONE;
else if (t == TBEGIN)
t = TEND;
else
synexpect(-1);
n1->nfor.body = list(0);
if (readtoken() != t)
synexpect(t);
break;
case TCASE:
n1 = (union node *)stalloc(sizeof (struct ncase));
n1->type = NCASE;
if (readtoken() != TWORD)
synexpect(TWORD);
n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
n2->type = NARG;
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
n2->narg.next = NULL;
while (readtoken() == TNL);
if (lasttoken != TWORD || ! equal(wordtext, "in"))
synerror("expecting \"in\"");
cpp = &n1->ncase.cases;
while (checkkwd(), readtoken() == TWORD) {
*cpp = cp = (union node *)stalloc(sizeof (struct nclist));
cp->type = NCLIST;
app = &cp->nclist.pattern;
for (;;) {
*app = ap = (union node *)stalloc(sizeof (struct narg));
ap->type = NARG;
ap->narg.text = wordtext;
ap->narg.backquote = backquotelist;
if (readtoken() != TPIPE)
break;
app = &ap->narg.next;
if (readtoken() != TWORD)
synexpect(TWORD);
}
ap->narg.next = NULL;
if (lasttoken != TRP)
synexpect(TRP);
cp->nclist.body = list(0);
if ((t = readtoken()) == TESAC)
tokpushback++;
else if (t != TENDCASE)
synexpect(TENDCASE);
cpp = &cp->nclist.next;
}
*cpp = NULL;
if (lasttoken != TESAC)
synexpect(TESAC);
break;
case TLP:
n1 = (union node *)stalloc(sizeof (struct nredir));
n1->type = NSUBSHELL;
n1->nredir.n = list(0);
n1->nredir.redirect = NULL;
if (readtoken() != TRP)
synexpect(TRP);
break;
case TBEGIN:
n1 = list(0);
if (readtoken() != TEND)
synexpect(TEND);
break;
case TWORD:
case TREDIR:
tokpushback++;
return simplecmd();
default:
synexpect(-1);
}
/* Now check for redirection which may follow command */
rpp = &redir;
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback++;
*rpp = NULL;
if (redir) {
if (n1->type != NSUBSHELL) {
n2 = (union node *)stalloc(sizeof (struct nredir));
n2->type = NREDIR;
n2->nredir.n = n1;
n1 = n2;
}
n1->nredir.redirect = redir;
}
return n1;
}
