static void comsubst(void)
{
/* command substn */
FILEBLK cb;
register char d;
register STKPTR savptr = fixstak();
usestak();
while ((d = readc()) != SQUOTE && d)
pushstak(d);
{
register char *argc;
trim(argc = fixstak());
push(&cb);
estabf(argc);
}
{
register TREPTR t =
makefork(FPOU, cmd(EOFSYM, MTFLG | NLFLG));
int pv[2];
/* this is done like this so that the pipe
* is open only when needed
*/
chkpipe(pv);
initf(pv[INPIPE]);
execute(t, 0, 0, pv);
close(pv[OTPIPE]);
}
tdystak(savptr);
staktop = movstr(savptr, stakbot);
while (d = readc())
pushstak(d | quote);
await(0);
while (stakbot != staktop) {
if ((*--staktop & STRIP) != NL) {
++staktop;
break;
}
}
pop();
}
int execute(TREPTR argt, int execflg, int *pf1, int *pf2)
{
/* `stakbot' is preserved by this routine */
register TREPTR t;
STKPTR sav = savstak();
sigchk();
if ((t = argt) && execbrk == 0) {
register int treeflgs;
int oldexit, type;
register char **com;
treeflgs = t->tretyp;
type = treeflgs & COMMSK;
oldexit = exitval;
exitval = 0;
switch (type) {
case TCOM:
{
STRING a1;
int argn, internal;
ARGPTR schain = gchain;
IOPTR io = t->treio;
gchain = 0;
argn = getarg((void *)t);/*FIXME*/
com = scan(argn);
a1 = com[1];
gchain = schain;
if ((internal = syslook(com[0], commands)) || argn == 0)
setlist(((COMPTR) t)->comset, 0);
if (argn && (flags & noexec) == 0) { /* print command if execpr */
if (flags & execpr) {
argn = 0;
prs(execpmsg);
while (com[argn] != ENDARGS) {
prs(com[argn++]);
blank();
}
newline();
}
switch (internal) {
case SYSDOT:
if (a1) {
register int f;
if ((f = pathopen(getpath(a1), a1)) < 0)
failed(a1, notfound);
else
execexp(0, f);
}
break;
case SYSTIMES:
{
struct tms t;
times(&t);
prt(t.tms_cutime);
blank();
prt(t.tms_cstime);
newline();
}
break;
case SYSEXIT:
exitsh(a1 ? stoi(a1) : oldexit);
case SYSNULL:
io = 0;
break;
case SYSCONT:
execbrk = -loopcnt;
break;
case SYSBREAK:
if ((execbrk = loopcnt) && a1)
breakcnt = stoi(a1);
break;
case SYSTRAP:
if (a1) {
BOOL clear;
if ((clear = digit(*a1)) == 0)
++com;
while (*++com) {
int i;
if ((i = stoi(*com)) >= MAXTRAP || i < MINTRAP)
failed(*com, badtrap);
else if (clear)
clrsig(i);
else {
replace(&trapcom[i], a1);
if (*a1)
getsig(i);
else
ignsig(i);
}
}
} else { /* print out current traps */
int i;
for (i = 0; i < MAXTRAP; i++) {
if (trapcom[i]) {
prn(i);
prs(colon);
prs(trapcom[i]);
newline();
}
}
}
break;
case SYSEXEC:
com++;
initio(io);
ioset = 0;
io = 0;
if (a1 == 0)
break;
case SYSLOGIN:
flags |= forked;
oldsigs();
execa((const char **)com);
done();
case SYSCD:
if (flags & rshflg)
failed(com[0], restricted);
else if ((a1 == 0 && (a1 = (char *)homenod.namval) == 0) || chdir(a1) < 0) /* FIXME */
failed(a1, baddir);
break;
case SYSSHFT:
if (dolc < 1)
error(badshift);
else {
dolv++;
dolc--;
}
assnum(&dolladr, dolc);
break;
case SYSWAIT:
await(-1);
break;
case SYSREAD:
exitval = readvar(&com[1]);
break;
/*
case SYSTST:
exitval=testcmd(com);
break;
*/
case SYSSET:
if (a1) {
int argc;
argc = options(argn, (const char **)com);
if (argc > 1)
setargs((const char **)com + argn - argc);
} else if (((COMPTR) t)->comset == 0)
/* Scan name chain and print */
namscan(printnam);
break;
case SYSRDONLY:
exitval = N_RDONLY;
case SYSXPORT:
if (exitval == 0)
exitval = N_EXPORT;;
if (a1) {
while (*++com)
attrib(lookup(*com), exitval);
} else {
namscan(printflg);
}
exitval = 0;
break;
case SYSEVAL:
if (a1)
execexp(a1, (UFD)&com[2]); /* FIXME */
break;
case SYSUMASK:
if (a1) {
int c, i;
i = 0;
while ((c = *a1++) >= '0' && c <= '7')
i = (i << 3) + c - '0';
umask(i);
} else {
int i, j;
umask(i = umask(0));
prc('0');
for (j = 6; j >= 0; j -= 3)
prc(((i >> j) & 07) + '0');
newline();
}
break;
default:
internal = builtin(argn, com);
}
if (internal) {
if (io)
error(illegal);
chktrap();
break;
}
} else if (t->treio == 0)
break;
}
case TFORK:
if (execflg && (treeflgs & (FAMP | FPOU)) == 0)
parent = 0;
else {
while ((parent = fork()) == -1) {
sigchk();
alarm(10);
pause();
}
}
if (parent) { /* This is the parent branch of fork; */
/* it may or may not wait for the child. */
if (treeflgs & FPRS && flags & ttyflg) {
prn(parent);
newline();
}
if (treeflgs & FPCL)
closepipe(pf1);
if ((treeflgs & (FAMP | FPOU)) == 0)
await(parent);
else if ((treeflgs & FAMP) == 0)
post(parent);
else
assnum(&pcsadr, parent);
chktrap();
break;
} else { /* this is the forked branch (child) of execute */
flags |= forked;
iotemp = 0;
postclr();
settmp();
/* Turn off INTR and QUIT if `FINT' */
/* Reset ramaining signals to parent */
/* except for those `lost' by trap */
oldsigs();
if (treeflgs & FINT) {
signal(INTR, SIG_IGN);
signal(QUIT, SIG_IGN);
}
/* pipe in or out */
if (treeflgs & FPIN) {
sh_rename(pf1[INPIPE], 0);
close(pf1[OTPIPE]);
}
if (treeflgs & FPOU) {
sh_rename(pf2[OTPIPE], 1);
close(pf2[INPIPE]);
}
/* default std input for & */
if (treeflgs & FINT && ioset == 0)
sh_rename(chkopen(devnull), 0);
/* io redirection */
initio(t->treio);
if (type != TCOM)
execute(((FORKPTR) t)->forktre, 1, NULL, NULL);
else if (com[0] != ENDARGS) {
setlist(((COMPTR) t)->comset, N_EXPORT);
execa((const char **)com);
}
done();
}
case TPAR:
sh_rename(dup(2), output);
execute(((PARPTR) t)->partre, execflg, NULL, NULL);
done();
case TFIL:
{
int pv[2];
chkpipe(pv);
if (execute(((LSTPTR) t)->lstlef, 0, pf1, pv) == 0)
execute(((LSTPTR) t)->lstrit, execflg, pv, pf2);
else
closepipe(pv);
break;
}
case TLST:
execute(((LSTPTR) t)->lstlef, 0, NULL, NULL);
execute(((LSTPTR) t)->lstrit, execflg, NULL, NULL);
break;
case TAND:
if (execute(((LSTPTR) t)->lstlef, 0, NULL, NULL) == 0)
execute(((LSTPTR) t)->lstrit, execflg, NULL, NULL);
break;
case TORF:
if (execute(((LSTPTR) t)->lstlef, 0, NULL, NULL) != 0)
execute(((LSTPTR) t)->lstrit, execflg, NULL, NULL);
break;
case TFOR:
{
NAMPTR n = lookup(((FORPTR) t)->fornam);
char **args;
DOLPTR argsav = 0;
if (((FORPTR) t)->forlst == 0) {
args = (char **)dolv + 1;
argsav = useargs();
} else {
ARGPTR schain = gchain;
gchain = 0;
trim((args = scan(getarg(((FORPTR) t)->forlst)))[0]);
gchain = schain;
}
loopcnt++;
while (*args != ENDARGS && execbrk == 0) {
assign(n, *args++);
execute(((FORPTR) t)->fortre, 0, NULL, NULL);
if (execbrk < 0) {
execbrk = 0;
}
}
if (breakcnt)
breakcnt--;
execbrk = breakcnt;
loopcnt--;
argfor = freeargs(argsav);
break;
}
case TWH:
case TUN:
{
int i = 0;
loopcnt++;
while (execbrk == 0 && (execute(((WHPTR) t)->whtre, 0, NULL, NULL) == 0) == (type == TWH)) {
i = execute(((WHPTR) t)->dotre, 0, NULL, NULL);
if (execbrk < 0)
execbrk = 0;
}
if (breakcnt)
breakcnt--;
execbrk = breakcnt;
loopcnt--;
exitval = i;
break;
}
case TIF:
if (execute(((IFPTR) t)->iftre, 0, NULL, NULL) == 0)
execute(((IFPTR) t)->thtre, execflg, NULL, NULL);
else
execute(((IFPTR) t)->eltre, execflg, NULL, NULL);
break;
case TSW:
{
register char *r = mactrim(((SWPTR) t)->swarg);
t = (TREPTR) ((SWPTR) t)->swlst;
while (t) {
ARGPTR rex = ((REGPTR) t)->regptr;
while (rex) {
register char *s;
if (gmatch(r, s = macro(rex->argval)) || (trim(s), eq(r, s))) {
execute(((REGPTR)t)->regcom, 0, NULL, NULL);
t = 0;
break;
} else
rex = ((ARGPTR)rex)->argnxt;
}
if (t)
t = (TREPTR) ((REGPTR) t)->regnxt;
}
}
break;
}
exitset();
}
