static void dopipe(Node *n) {
int i, j, sp, pid, fd_prev, fd_out, pids[512], stats[512], p[2];
bool intr;
Node *r;
fd_prev = fd_out = 1;
for (r = n, i = 0; r != NULL && r->type == nPipe; r = r->u[2].p, i++) {
if (i > 500) /* the only hard-wired limit in rc? */
rc_error("pipe too long");
if (pipe(p) < 0) {
uerror("pipe");
rc_error(NULL);
}
if ((pid = rc_fork()) == 0) {
setsigdefaults(FALSE);
redirq = NULL; /* clear preredir queue */
mvfd(p[0], r->u[1].i);
if (fd_prev != 1)
mvfd(fd_prev, fd_out);
close(p[1]);
walk(r->u[3].p, FALSE);
exit(getstatus());
}
if (fd_prev != 1)
close(fd_prev); /* parent must close all pipe fd's */
pids[i] = pid;
fd_prev = p[1];
fd_out = r->u[0].i;
close(p[0]);
}
if ((pid = rc_fork()) == 0) {
setsigdefaults(FALSE);
mvfd(fd_prev, fd_out);
walk(r, FALSE);
exit(getstatus());
/* NOTREACHED */
}
redirq = NULL; /* clear preredir queue */
close(fd_prev);
pids[i++] = pid;
/* collect statuses */
intr = FALSE;
for (j = 0; j < i; j++) {
rc_wait4(pids[j], &sp, TRUE);
stats[j] = sp;
intr |= (sp == SIGINT);
}
setpipestatus(stats, i);
sigchk();
}
static List *mkcmdarg(Node *n) {
int fd;
char *name;
Edata efifo;
Estack *e = enew(Estack);
List *ret = nnew(List);
static int fifonumber = 0;
name = nprint("/tmp/rc%d.%d", getpid(), fifonumber++);
if (mkfifo(name, 0666) < 0) {
uerror("mkfifo");
return NULL;
}
if (rc_fork() == 0) {
setsigdefaults(FALSE);
fd = rc_open(name, (n->u[0].i != rFrom) ? rFrom : rCreate); /* stupid hack */
if (fd < 0) {
uerror("open");
exit(1);
}
if (mvfd(fd, (n->u[0].i == rFrom)) < 0) /* same stupid hack */
exit(1);
redirq = NULL;
walk(n->u[2].p, FALSE);
exit(getstatus());
}
efifo.name = name;
except(eFifo, efifo, e);
ret->w = name;
ret->m = NULL;
ret->n = NULL;
return ret;
}
static List *mkcmdarg(Node *n) {
char *name;
List *ret = nnew(List);
Estack *e = nnew(Estack);
Edata efd;
int p[2];
if (pipe(p) < 0) {
uerror("pipe");
return NULL;
}
if (rc_fork() == 0) {
setsigdefaults(FALSE);
if (mvfd(p[n->u[0].i == rFrom], n->u[0].i == rFrom) < 0) /* stupid hack */
exit(1);
close(p[n->u[0].i != rFrom]);
redirq = NULL;
walk(n->u[2].p, FALSE);
exit(getstatus());
}
#if HAVE_DEV_FD
name = nprint("/dev/fd/%d", p[n->u[0].i != rFrom]);
#else
name = nprint("/proc/self/fd/%d", p[n->u[0].i != rFrom]);
#endif
efd.fd = p[n->u[0].i != rFrom];
except(eFd, efd, e);
close(p[n->u[0].i == rFrom]);
ret->w = name;
ret->m = NULL;
ret->n = NULL;
return ret;
}
static List *backq(Node *ifs, Node *n) {
int p[2], sp;
pid_t pid;
List *bq;
struct termios t;
if (n == NULL)
return NULL;
if (pipe(p) < 0) {
uerror("pipe");
rc_error(NULL);
}
if (interactive)
tcgetattr(0, &t);
if ((pid = rc_fork()) == 0) {
mvfd(p[1], 1);
close(p[0]);
redirq = NULL;
walk(n, FALSE);
exit(getstatus());
}
close(p[1]);
bq = bqinput(glom(ifs), p[0]);
close(p[0]);
rc_wait4(pid, &sp, TRUE);
if (interactive && WIFSIGNALED(sp))
tcsetattr(0, TCSANOW, &t);
statprint(-1, sp);
varassign("bqstatus", word(strstatus(sp), NULL), FALSE);
sigchk();
return bq;
}
extern void doredirs() {
List *fname;
int fd, p[2];
Rq *r;
for (r = redirq; r != NULL; r = r->n) {
switch(r->r->type) {
default:
panic("unexpected node in doredirs");
/* NOTREACHED */
case nRedir:
if (r->r->u[0].i == rHerestring) {
fname = flatten(glom(r->r->u[2].p)); /* fname is really a string */
if (pipe(p) < 0) {
uerror("pipe");
rc_error(NULL);
}
if (rc_fork() == 0) { /* child writes to pipe */
setsigdefaults(FALSE);
close(p[0]);
if (fname != NULL)
writeall(p[1], fname->w, strlen(fname->w));
exit(0);
} else {
close(p[1]);
if (mvfd(p[0], r->r->u[1].i) < 0)
rc_error(NULL);
}
} else {
fname = glob(glom(r->r->u[2].p));
if (fname == NULL)
rc_error("null filename in redirection");
if (fname->n != NULL)
rc_error("multi-word filename in redirection");
switch (r->r->u[0].i) {
default:
panic("unexpected node in doredirs");
/* NOTREACHED */
case rCreate: case rAppend: case rFrom:
fd = rc_open(fname->w, r->r->u[0].i);
break;
}
if (fd < 0) {
uerror(fname->w);
rc_error(NULL);
}
if (mvfd(fd, r->r->u[1].i) < 0)
rc_error(NULL);
}
break;
case nDup:
if (r->r->u[2].i == -1)
close(r->r->u[1].i);
else if (r->r->u[2].i != r->r->u[1].i) {
if (dup2(r->r->u[2].i, r->r->u[1].i) < 0) {
uerror("dup2");
rc_error(NULL);
}
}
}
}
redirq = NULL;
}
extern bool walk(Node *n, bool parent) {
top: sigchk();
if (n == NULL) {
if (!parent)
exit(0);
set(TRUE);
return TRUE;
}
switch (n->type) {
case nArgs: case nBackq: case nConcat: case nCount:
case nFlat: case nLappend: case nRedir: case nVar:
case nVarsub: case nWord:
exec(glob(glom(n)), parent); /* simple command */
break;
case nBody:
walk(n->u[0].p, TRUE);
WALK(n->u[1].p, parent);
/* WALK doesn't fall through */
case nNowait: {
int pid;
if ((pid = rc_fork()) == 0) {
#if defined(RC_JOB) && defined(SIGTTOU) && defined(SIGTTIN) && defined(SIGTSTP)
setsigdefaults(FALSE);
rc_signal(SIGTTOU, SIG_IGN); /* Berkeleyized version: put it in a new pgroup. */
rc_signal(SIGTTIN, SIG_IGN);
rc_signal(SIGTSTP, SIG_IGN);
setpgid(0, getpid());
#else
setsigdefaults(TRUE); /* ignore SIGINT, SIGQUIT, SIGTERM */
#endif
mvfd(rc_open("/dev/null", rFrom), 0);
walk(n->u[0].p, FALSE);
exit(getstatus());
}
if (interactive)
fprint(2, "%d\n", pid);
varassign("apid", word(nprint("%d", pid), NULL), FALSE);
redirq = NULL; /* kill pre-redir queue */
break;
}
case nAndalso: {
bool oldcond = cond;
cond = TRUE;
if (walk(n->u[0].p, TRUE)) {
cond = oldcond;
WALK(n->u[1].p, parent);
} else
cond = oldcond;
break;
}
case nOrelse: {
bool oldcond = cond;
cond = TRUE;
if (!walk(n->u[0].p, TRUE)) {
cond = oldcond;
WALK(n->u[1].p, parent);
} else
cond = oldcond;
break;
}
case nBang:
set(!walk(n->u[0].p, TRUE));
break;
case nIf: {
bool oldcond = cond;
Node *true_cmd = n->u[1].p, *false_cmd = NULL;
if (true_cmd != NULL && true_cmd->type == nElse) {
false_cmd = true_cmd->u[1].p;
true_cmd = true_cmd->u[0].p;
}
cond = TRUE;
if (!walk(n->u[0].p, TRUE))
true_cmd = false_cmd; /* run the else clause */
cond = oldcond;
WALK(true_cmd, parent);
}
case nWhile: {
Jbwrap j;
Edata jbreak;
Estack e1, e2;
bool testtrue, oldcond = cond;
cond = TRUE;
if (!walk(n->u[0].p, TRUE)) { /* prevent spurious breaks inside test */
cond = oldcond;
break;
}
if (sigsetjmp(j.j, 1))
break;
jbreak.jb = &j;
except(eBreak, jbreak, &e1);
do {
Edata block;
block.b = newblock();
cond = oldcond;
except(eArena, block, &e2);
walk(n->u[1].p, TRUE);
testtrue = walk(n->u[0].p, TRUE);
unexcept(); /* eArena */
cond = TRUE;
} while (testtrue);
cond = oldcond;
unexcept(); /* eBreak */
break;
}
case nForin: {
List *l, *var = glom(n->u[0].p);
Jbwrap j;
Estack e1, e2;
Edata jbreak;
if (sigsetjmp(j.j, 1))
break;
jbreak.jb = &j;
except(eBreak, jbreak, &e1);
for (l = listcpy(glob(glom(n->u[1].p)), nalloc); l != NULL; l = l->n) {
Edata block;
assign(var, word(l->w, NULL), FALSE);
block.b = newblock();
except(eArena, block, &e2);
walk(n->u[2].p, TRUE);
unexcept(); /* eArena */
}
unexcept(); /* eBreak */
break;
}
case nSubshell:
if (dofork(TRUE)) {
setsigdefaults(FALSE);
walk(n->u[0].p, FALSE);
rc_exit(getstatus());
}
break;
case nAssign:
if (n->u[0].p == NULL)
rc_error("null variable name");
assign(glom(n->u[0].p), glob(glom(n->u[1].p)), FALSE);
set(TRUE);
break;
case nPipe:
dopipe(n);
break;
case nNewfn: {
List *l = glom(n->u[0].p);
if (l == NULL)
rc_error("null function name");
while (l != NULL) {
if (dashex)
prettyprint_fn(2, l->w, n->u[1].p);
fnassign(l->w, n->u[1].p);
l = l->n;
}
set(TRUE);
break;
}
case nRmfn: {
List *l = glom(n->u[0].p);
while (l != NULL) {
if (dashex)
fprint(2, "fn %S\n", l->w);
fnrm(l->w);
l = l->n;
}
set(TRUE);
break;
}
case nDup:
redirq = NULL;
break; /* Null command */
case nMatch: {
List *a = glob(glom(n->u[0].p)), *b = glom(n->u[1].p);
if (dashex)
fprint(2, (a != NULL && a->n != NULL) ? "~ (%L) %L\n" : "~ %L %L\n", a, " ", b, " ");
set(lmatch(a, b));
break;
}
case nSwitch: {
List *v = glom(n->u[0].p);
while (1) {
do {
n = n->u[1].p;
if (n == NULL)
return istrue();
} while (n->u[0].p == NULL || n->u[0].p->type != nCase);
if (lmatch(v, glom(n->u[0].p->u[0].p))) {
for (n = n->u[1].p; n != NULL && (n->u[0].p == NULL || n->u[0].p->type != nCase); n = n->u[1].p)
walk(n->u[0].p, TRUE);
break;
}
}
break;
}
case nPre: {
List *v;
if (n->u[0].p->type == nRedir || n->u[0].p->type == nDup) {
if (redirq == NULL && !dofork(parent)) /* subshell on first preredir */
break;
setsigdefaults(FALSE);
qredir(n->u[0].p);
if (!haspreredir(n->u[1].p))
doredirs(); /* no more preredirs, empty queue */
walk(n->u[1].p, FALSE);
rc_exit(getstatus());
/* NOTREACHED */
} else if (n->u[0].p->type == nAssign) {
if (isallpre(n->u[1].p)) {
walk(n->u[0].p, TRUE);
WALK(n->u[1].p, parent);
} else {
Estack e;
Edata var;
v = glom(n->u[0].p->u[0].p);
assign(v, glob(glom(n->u[0].p->u[1].p)), TRUE);
var.name = v->w;
except(eVarstack, var, &e);
walk(n->u[1].p, parent);
varrm(v->w, TRUE);
unexcept(); /* eVarstack */
}
} else
panic("unexpected node in preredir section of walk");
break;
}
case nBrace:
if (n->u[1].p == NULL) {
WALK(n->u[0].p, parent);
} else if (dofork(parent)) {
setsigdefaults(FALSE);
walk(n->u[1].p, TRUE); /* Do redirections */
redirq = NULL; /* Reset redirection queue */
walk(n->u[0].p, FALSE); /* Do commands */
rc_exit(getstatus());
/* NOTREACHED */
}
break;
case nEpilog:
qredir(n->u[0].p);
if (n->u[1].p != NULL) {
WALK(n->u[1].p, parent); /* Do more redirections. */
} else {
doredirs(); /* Okay, we hit the bottom. */
}
break;
case nNmpipe:
rc_error("named pipes cannot be executed as commands");
/* NOTREACHED */
default:
panic("unknown node in walk");
/* NOTREACHED */
}
return istrue();
}
