STATIC void
evalsubshell(union node *n, int flags)
{
struct job *jp;
int backgnd = (n->type == NBACKGND);
expredir(n->nredir.redirect);
jp = makejob(n, 1);
if (forkshell(jp, n, backgnd) == 0) {
if (backgnd)
flags &=~ EV_TESTED;
redirect(n->nredir.redirect, 0);
evaltree(n->nredir.n, flags | EV_EXIT); /* never returns */
}
if (! backgnd) {
INTOFF;
exitstatus = waitforjob(jp, (int *)NULL);
INTON;
}
}
static void
evalsubshell(union node *n, int flags)
{
struct job *jp;
int backgnd = (n->type == NBACKGND);
oexitstatus = exitstatus;
expredir(n->nredir.redirect);
if ((!backgnd && flags & EV_EXIT && !have_traps()) ||
forkshell(jp = makejob(n, 1), n, backgnd) == 0) {
if (backgnd)
flags &=~ EV_TESTED;
redirect(n->nredir.redirect, 0);
evaltree(n->nredir.n, flags | EV_EXIT); /* never returns */
} else if (! backgnd) {
INTOFF;
exitstatus = waitforjob(jp, (int *)NULL);
INTON;
}
}
STATIC void
evalsubshell(shinstance *psh, union node *n, int flags)
{
struct job *jp;
int backgnd = (n->type == NBACKGND);
expredir(psh, n->nredir.redirect);
INTOFF;
jp = makejob(psh, n, 1);
if (forkshell(psh, jp, n, backgnd ? FORK_BG : FORK_FG) == 0) {
INTON;
if (backgnd)
flags &=~ EV_TESTED;
redirect(psh, n->nredir.redirect, 0);
/* never returns */
evaltree(psh, n->nredir.n, flags | EV_EXIT);
}
if (! backgnd)
psh->exitstatus = waitforjob(psh, jp);
INTON;
}
static void
evalredir(union node *n, int flags)
{
struct jmploc jmploc;
struct jmploc *savehandler;
volatile int in_redirect = 1;
oexitstatus = exitstatus;
expredir(n->nredir.redirect);
savehandler = handler;
if (setjmp(jmploc.loc)) {
int e;
handler = savehandler;
e = exception;
popredir();
if (e == EXERROR || e == EXEXEC) {
if (in_redirect) {
exitstatus = 2;
return;
}
}
longjmp(handler->loc, 1);
} else {
INTOFF;
handler = &jmploc;
redirect(n->nredir.redirect, REDIR_PUSH);
in_redirect = 0;
INTON;
evaltree(n->nredir.n, flags);
}
INTOFF;
handler = savehandler;
popredir();
INTON;
}
static void
evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
{
union node *argp;
struct arglist arglist;
struct arglist varlist;
char **argv;
int argc;
char **envp;
int varflag;
struct strlist *sp;
int mode;
int pip[2];
struct cmdentry cmdentry;
struct job *jp;
struct jmploc jmploc;
struct jmploc *savehandler;
char *savecmdname;
struct shparam saveparam;
struct localvar *savelocalvars;
struct parsefile *savetopfile;
volatile int e;
char *lastarg;
int realstatus;
int do_clearcmdentry;
const char *path = pathval();
/* First expand the arguments. */
TRACE(("evalcommand(%p, %d) called\n", (void *)cmd, flags));
arglist.lastp = &arglist.list;
varlist.lastp = &varlist.list;
varflag = 1;
jp = NULL;
do_clearcmdentry = 0;
oexitstatus = exitstatus;
exitstatus = 0;
for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
if (varflag && isassignment(argp->narg.text)) {
expandarg(argp, varflag == 1 ? &varlist : &arglist,
EXP_VARTILDE);
continue;
} else if (varflag == 1)
varflag = isdeclarationcmd(&argp->narg) ? 2 : 0;
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
}
*arglist.lastp = NULL;
*varlist.lastp = NULL;
expredir(cmd->ncmd.redirect);
argc = 0;
for (sp = arglist.list ; sp ; sp = sp->next)
argc++;
/* Add one slot at the beginning for tryexec(). */
argv = stalloc(sizeof (char *) * (argc + 2));
argv++;
for (sp = arglist.list ; sp ; sp = sp->next) {
TRACE(("evalcommand arg: %s\n", sp->text));
*argv++ = sp->text;
}
*argv = NULL;
lastarg = NULL;
if (iflag && funcnest == 0 && argc > 0)
lastarg = argv[-1];
argv -= argc;
/* Print the command if xflag is set. */
if (xflag) {
char sep = 0;
const char *p, *ps4;
ps4 = expandstr(ps4val());
out2str(ps4 != NULL ? ps4 : ps4val());
for (sp = varlist.list ; sp ; sp = sp->next) {
if (sep != 0)
out2c(' ');
p = strchr(sp->text, '=');
if (p != NULL) {
p++;
outbin(sp->text, p - sp->text, out2);
out2qstr(p);
} else
out2qstr(sp->text);
sep = ' ';
}
for (sp = arglist.list ; sp ; sp = sp->next) {
if (sep != 0)
out2c(' ');
/* Disambiguate command looking like assignment. */
if (sp == arglist.list &&
strchr(sp->text, '=') != NULL &&
strchr(sp->text, '\'') == NULL) {
out2c('\'');
out2str(sp->text);
out2c('\'');
} else
out2qstr(sp->text);
sep = ' ';
}
out2c('\n');
flushout(&errout);
}
/* Now locate the command. */
if (argc == 0) {
/* Variable assignment(s) without command */
cmdentry.cmdtype = CMDBUILTIN;
cmdentry.u.index = BLTINCMD;
cmdentry.special = 0;
} else {
static const char PATH[] = "PATH=";
int cmd_flags = 0, bltinonly = 0;
/*
* Modify the command lookup path, if a PATH= assignment
* is present
*/
for (sp = varlist.list ; sp ; sp = sp->next)
if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0) {
path = sp->text + sizeof(PATH) - 1;
/*
* On `PATH=... command`, we need to make
* sure that the command isn't using the
* non-updated hash table of the outer PATH
* setting and we need to make sure that
* the hash table isn't filled with items
* from the temporary setting.
*
* It would be better to forbit using and
* updating the table while this command
* runs, by the command finding mechanism
* is heavily integrated with hash handling,
* so we just delete the hash before and after
* the command runs. Partly deleting like
* changepatch() does doesn't seem worth the
* bookinging effort, since most such runs add
* directories in front of the new PATH.
*/
clearcmdentry();
do_clearcmdentry = 1;
}
for (;;) {
if (bltinonly) {
cmdentry.u.index = find_builtin(*argv, &cmdentry.special);
if (cmdentry.u.index < 0) {
cmdentry.u.index = BLTINCMD;
argv--;
argc++;
break;
}
} else
find_command(argv[0], &cmdentry, cmd_flags, path);
/* implement the bltin and command builtins here */
if (cmdentry.cmdtype != CMDBUILTIN)
break;
if (cmdentry.u.index == BLTINCMD) {
if (argc == 1)
break;
argv++;
argc--;
bltinonly = 1;
} else if (cmdentry.u.index == COMMANDCMD) {
if (argc == 1)
break;
if (!strcmp(argv[1], "-p")) {
if (argc == 2)
break;
if (argv[2][0] == '-') {
if (strcmp(argv[2], "--"))
break;
if (argc == 3)
break;
argv += 3;
argc -= 3;
} else {
argv += 2;
argc -= 2;
}
path = _PATH_STDPATH;
clearcmdentry();
do_clearcmdentry = 1;
} else if (!strcmp(argv[1], "--")) {
if (argc == 2)
break;
argv += 2;
argc -= 2;
} else if (argv[1][0] == '-')
break;
else {
argv++;
argc--;
}
cmd_flags |= DO_NOFUNC;
bltinonly = 0;
} else
break;
}
/*
* Special builtins lose their special properties when
* called via 'command'.
*/
if (cmd_flags & DO_NOFUNC)
cmdentry.special = 0;
}
/* Fork off a child process if necessary. */
if (((cmdentry.cmdtype == CMDNORMAL || cmdentry.cmdtype == CMDUNKNOWN)
&& ((flags & EV_EXIT) == 0 || have_traps()))
|| ((flags & EV_BACKCMD) != 0
&& (cmdentry.cmdtype != CMDBUILTIN ||
!safe_builtin(cmdentry.u.index, argc, argv)))) {
jp = makejob(cmd, 1);
mode = FORK_FG;
if (flags & EV_BACKCMD) {
mode = FORK_NOJOB;
if (pipe(pip) < 0)
error("Pipe call failed: %s", strerror(errno));
}
if (cmdentry.cmdtype == CMDNORMAL &&
cmd->ncmd.redirect == NULL &&
varlist.list == NULL &&
(mode == FORK_FG || mode == FORK_NOJOB) &&
!disvforkset() && !iflag && !mflag) {
vforkexecshell(jp, argv, environment(), path,
cmdentry.u.index, flags & EV_BACKCMD ? pip : NULL);
goto parent;
}
if (forkshell(jp, cmd, mode) != 0)
goto parent; /* at end of routine */
if (flags & EV_BACKCMD) {
FORCEINTON;
close(pip[0]);
if (pip[1] != 1) {
dup2(pip[1], 1);
close(pip[1]);
}
flags &= ~EV_BACKCMD;
}
flags |= EV_EXIT;
}
/* This is the child process if a fork occurred. */
/* Execute the command. */
if (cmdentry.cmdtype == CMDFUNCTION) {
#ifdef DEBUG
trputs("Shell function: "); trargs(argv);
#endif
saveparam = shellparam;
shellparam.malloc = 0;
shellparam.reset = 1;
shellparam.nparam = argc - 1;
shellparam.p = argv + 1;
shellparam.optnext = NULL;
INTOFF;
savelocalvars = localvars;
localvars = NULL;
reffunc(cmdentry.u.func);
savehandler = handler;
if (setjmp(jmploc.loc)) {
freeparam(&shellparam);
shellparam = saveparam;
popredir();
unreffunc(cmdentry.u.func);
poplocalvars();
localvars = savelocalvars;
funcnest--;
handler = savehandler;
longjmp(handler->loc, 1);
}
handler = &jmploc;
funcnest++;
redirect(cmd->ncmd.redirect, REDIR_PUSH);
INTON;
for (sp = varlist.list ; sp ; sp = sp->next)
mklocal(sp->text);
exitstatus = oexitstatus;
evaltree(getfuncnode(cmdentry.u.func),
flags & (EV_TESTED | EV_EXIT));
INTOFF;
unreffunc(cmdentry.u.func);
poplocalvars();
localvars = savelocalvars;
freeparam(&shellparam);
shellparam = saveparam;
handler = savehandler;
funcnest--;
popredir();
INTON;
if (evalskip == SKIPFUNC) {
evalskip = 0;
skipcount = 0;
}
if (jp)
exitshell(exitstatus);
} else if (cmdentry.cmdtype == CMDBUILTIN) {
#ifdef DEBUG
trputs("builtin command: "); trargs(argv);
#endif
mode = (cmdentry.u.index == EXECCMD)? 0 : REDIR_PUSH;
if (flags == EV_BACKCMD) {
memout.nleft = 0;
memout.nextc = memout.buf;
memout.bufsize = 64;
mode |= REDIR_BACKQ;
}
savecmdname = commandname;
savetopfile = getcurrentfile();
cmdenviron = varlist.list;
e = -1;
savehandler = handler;
if (setjmp(jmploc.loc)) {
e = exception;
if (e == EXINT)
exitstatus = SIGINT+128;
else if (e != EXEXIT)
exitstatus = 2;
goto cmddone;
}
handler = &jmploc;
redirect(cmd->ncmd.redirect, mode);
outclearerror(out1);
/*
* If there is no command word, redirection errors should
* not be fatal but assignment errors should.
*/
if (argc == 0)
cmdentry.special = 1;
listsetvar(cmdenviron, cmdentry.special ? 0 : VNOSET);
if (argc > 0)
bltinsetlocale();
commandname = argv[0];
argptr = argv + 1;
nextopt_optptr = NULL; /* initialize nextopt */
builtin_flags = flags;
exitstatus = (*builtinfunc[cmdentry.u.index])(argc, argv);
flushall();
if (outiserror(out1)) {
warning("write error on stdout");
if (exitstatus == 0 || exitstatus == 1)
exitstatus = 2;
}
cmddone:
if (argc > 0)
bltinunsetlocale();
cmdenviron = NULL;
out1 = &output;
out2 = &errout;
freestdout();
handler = savehandler;
commandname = savecmdname;
if (jp)
exitshell(exitstatus);
if (flags == EV_BACKCMD) {
backcmd->buf = memout.buf;
backcmd->nleft = memout.nextc - memout.buf;
memout.buf = NULL;
}
if (cmdentry.u.index != EXECCMD)
popredir();
if (e != -1) {
if ((e != EXERROR && e != EXEXEC)
|| cmdentry.special)
exraise(e);
popfilesupto(savetopfile);
if (flags != EV_BACKCMD)
FORCEINTON;
}
} else {
#ifdef DEBUG
trputs("normal command: "); trargs(argv);
#endif
redirect(cmd->ncmd.redirect, 0);
for (sp = varlist.list ; sp ; sp = sp->next)
setvareq(sp->text, VEXPORT|VSTACK);
envp = environment();
shellexec(argv, envp, path, cmdentry.u.index);
/*NOTREACHED*/
}
goto out;
parent: /* parent process gets here (if we forked) */
if (mode == FORK_FG) { /* argument to fork */
INTOFF;
exitstatus = waitforjob(jp, &realstatus);
INTON;
if (iflag && loopnest > 0 && WIFSIGNALED(realstatus)) {
evalskip = SKIPBREAK;
skipcount = loopnest;
}
} else if (mode == FORK_NOJOB) {
backcmd->fd = pip[0];
close(pip[1]);
backcmd->jp = jp;
}
out:
if (lastarg)
setvar("_", lastarg, 0);
if (do_clearcmdentry)
clearcmdentry();
}
void
evaltree(union node *n, int flags)
{
int checkexit = 0;
void (*evalfn)(union node *, int);
unsigned isor;
int status;
if (n == NULL) {
//TRACE(("evaltree(NULL) called\n"));
goto out;
}
#ifndef SMALL
displayhist = 1; /* show history substitutions done with fc */
#endif
TRACE(("pid %d, evaltree(%p: %d, %d, %p) called\n",
getpid(), n, n->type, flags));
switch (n->type) {
default:
#ifdef DEBUG
#ifndef USE_GLIBC_STDIO
flushout(out1);
#endif
break;
#endif
case NNOT:
evaltree(n->nnot.com, EV_TESTED);
status = !exitstatus;
goto setstatus;
case NREDIR:
expredir(n->nredir.redirect);
status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
if (!status) {
evaltree(n->nredir.n, flags & EV_TESTED);
status = exitstatus;
}
popredir(0);
goto setstatus;
case NCMD:
#ifdef notyet
if (eflag && !(flags & EV_TESTED))
checkexit = ~0;
evalcommand(n, flags, (struct backcmd *)NULL);
break;
#else
evalfn = evalcommand;
checkexit:
if (eflag && !(flags & EV_TESTED))
checkexit = ~0;
goto calleval;
#endif
case NFOR:
evalfn = evalfor;
goto calleval;
case NWHILE:
case NUNTIL:
evalfn = evalloop;
goto calleval;
case NSUBSHELL:
case NBACKGND:
evalfn = evalsubshell;
evalsubshell (n, flags);
case NPIPE:
evalfn = evalpipe;
#ifdef notyet
if (eflag && !(flags & EV_TESTED))
checkexit = ~0;
goto calleval;
#else
goto checkexit;
#endif
case NCASE:
evalfn = evalcase;
goto calleval;
case NAND:
case NOR:
case NSEMI:
#if NAND + 1 != NOR
#error NAND + 1 != NOR
#endif
#if NOR + 1 != NSEMI
#error NOR + 1 != NSEMI
#endif
isor = n->type - NAND;
evaltree(
n->nbinary.ch1,
(flags | ((isor >> 1) - 1)) & EV_TESTED
);
if (!exitstatus == isor)
break;
if (!evalskip) {
n = n->nbinary.ch2;
evaln:
evaltree(n, flags);
break;
calleval:
evalfn(n, flags);
break;
}
break;
case NIF:
evaltree(n->nif.test, EV_TESTED);
if (evalskip)
break;
if (exitstatus == 0) {
n = n->nif.ifpart;
goto evaln;
} else if (n->nif.elsepart) {
n = n->nif.elsepart;
goto evaln;
}
goto success;
case NDEFUN:
defun(n->narg.text, n->narg.next);
success:
status = 0;
setstatus:
exitstatus = status;
break;
}
out:
if ((checkexit & exitstatus) ||
(pendingsigs && dotrap()) ||
(flags & EV_EXIT))
exraise(EXEXIT);
}
static void
evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
{
struct stackmark smark;
union node *argp;
struct arglist arglist;
struct arglist varlist;
char **argv;
int argc;
char **envp;
int varflag;
struct strlist *sp;
int mode;
int pip[2];
struct cmdentry cmdentry;
struct job *jp;
struct jmploc jmploc;
struct jmploc *savehandler;
char *savecmdname;
struct shparam saveparam;
struct localvar *savelocalvars;
volatile int e;
char *lastarg;
int realstatus;
int do_clearcmdentry;
/* First expand the arguments. */
TRACE(("evalcommand(%p, %d) called\n", (void *)cmd, flags));
setstackmark(&smark);
arglist.lastp = &arglist.list;
varlist.lastp = &varlist.list;
varflag = 1;
do_clearcmdentry = 0;
oexitstatus = exitstatus;
exitstatus = 0;
for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
char *p = argp->narg.text;
if (varflag && is_name(*p)) {
do {
p++;
} while (is_in_name(*p));
if (*p == '=') {
expandarg(argp, &varlist, EXP_VARTILDE);
continue;
}
}
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
varflag = 0;
}
*arglist.lastp = NULL;
*varlist.lastp = NULL;
expredir(cmd->ncmd.redirect);
argc = 0;
for (sp = arglist.list ; sp ; sp = sp->next)
argc++;
argv = stalloc(sizeof (char *) * (argc + 1));
for (sp = arglist.list ; sp ; sp = sp->next) {
TRACE(("evalcommand arg: %s\n", sp->text));
*argv++ = sp->text;
}
*argv = NULL;
lastarg = NULL;
if (iflag && funcnest == 0 && argc > 0)
lastarg = argv[-1];
argv -= argc;
/* Print the command if xflag is set. */
if (xflag) {
char sep = 0;
const char *p;
out2str(ps4val());
for (sp = varlist.list ; sp ; sp = sp->next) {
if (sep != 0)
outc(' ', &errout);
p = sp->text;
while (*p != '=' && *p != '\0')
out2c(*p++);
if (*p != '\0') {
out2c(*p++);
out2qstr(p);
}
sep = ' ';
}
for (sp = arglist.list ; sp ; sp = sp->next) {
if (sep != 0)
outc(' ', &errout);
/* Disambiguate command looking like assignment. */
if (sp == arglist.list &&
strchr(sp->text, '=') != NULL &&
strchr(sp->text, '\'') == NULL) {
out2c('\'');
out2str(sp->text);
out2c('\'');
} else
out2qstr(sp->text);
sep = ' ';
}
outc('\n', &errout);
flushout(&errout);
}
/* Now locate the command. */
if (argc == 0) {
/* Variable assignment(s) without command */
cmdentry.cmdtype = CMDBUILTIN;
cmdentry.u.index = BLTINCMD;
cmdentry.special = 1;
} else {
static const char PATH[] = "PATH=";
char *path = pathval();
/*
* Modify the command lookup path, if a PATH= assignment
* is present
*/
for (sp = varlist.list ; sp ; sp = sp->next)
if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0) {
path = sp->text + sizeof(PATH) - 1;
/*
* On `PATH=... command`, we need to make
* sure that the command isn't using the
* non-updated hash table of the outer PATH
* setting and we need to make sure that
* the hash table isn't filled with items
* from the temporary setting.
*
* It would be better to forbit using and
* updating the table while this command
* runs, by the command finding mechanism
* is heavily integrated with hash handling,
* so we just delete the hash before and after
* the command runs. Partly deleting like
* changepatch() does doesn't seem worth the
* bookinging effort, since most such runs add
* directories in front of the new PATH.
*/
clearcmdentry(0);
do_clearcmdentry = 1;
}
find_command(argv[0], &cmdentry, 1, path);
if (cmdentry.cmdtype == CMDUNKNOWN) { /* command not found */
exitstatus = 127;
flushout(&errout);
return;
}
/* implement the bltin builtin here */
if (cmdentry.cmdtype == CMDBUILTIN && cmdentry.u.index == BLTINCMD) {
for (;;) {
argv++;
if (--argc == 0)
break;
if ((cmdentry.u.index = find_builtin(*argv,
&cmdentry.special)) < 0) {
outfmt(&errout, "%s: not found\n", *argv);
exitstatus = 127;
flushout(&errout);
return;
}
if (cmdentry.u.index != BLTINCMD)
break;
}
}
}
/* Fork off a child process if necessary. */
if (cmd->ncmd.backgnd
|| (cmdentry.cmdtype == CMDNORMAL
&& ((flags & EV_EXIT) == 0 || have_traps()))
|| ((flags & EV_BACKCMD) != 0
&& (cmdentry.cmdtype != CMDBUILTIN
|| cmdentry.u.index == CDCMD
|| cmdentry.u.index == DOTCMD
|| cmdentry.u.index == EVALCMD))
|| (cmdentry.cmdtype == CMDBUILTIN &&
cmdentry.u.index == COMMANDCMD)) {
jp = makejob(cmd, 1);
mode = cmd->ncmd.backgnd;
if (flags & EV_BACKCMD) {
mode = FORK_NOJOB;
if (pipe(pip) < 0)
error("Pipe call failed: %s", strerror(errno));
}
if (forkshell(jp, cmd, mode) != 0)
goto parent; /* at end of routine */
if (flags & EV_BACKCMD) {
FORCEINTON;
close(pip[0]);
if (pip[1] != 1) {
dup2(pip[1], 1);
close(pip[1]);
}
}
flags |= EV_EXIT;
}
/* This is the child process if a fork occurred. */
/* Execute the command. */
if (cmdentry.cmdtype == CMDFUNCTION) {
#ifdef DEBUG
trputs("Shell function: "); trargs(argv);
#endif
redirect(cmd->ncmd.redirect, REDIR_PUSH);
saveparam = shellparam;
shellparam.malloc = 0;
shellparam.reset = 1;
shellparam.nparam = argc - 1;
shellparam.p = argv + 1;
shellparam.optnext = NULL;
INTOFF;
savelocalvars = localvars;
localvars = NULL;
reffunc(cmdentry.u.func);
INTON;
savehandler = handler;
if (setjmp(jmploc.loc)) {
if (exception == EXSHELLPROC)
freeparam(&saveparam);
else {
freeparam(&shellparam);
shellparam = saveparam;
}
unreffunc(cmdentry.u.func);
poplocalvars();
localvars = savelocalvars;
handler = savehandler;
longjmp(handler->loc, 1);
}
handler = &jmploc;
for (sp = varlist.list ; sp ; sp = sp->next)
mklocal(sp->text);
funcnest++;
exitstatus = oexitstatus;
if (flags & EV_TESTED)
evaltree(getfuncnode(cmdentry.u.func), EV_TESTED);
else
evaltree(getfuncnode(cmdentry.u.func), 0);
funcnest--;
INTOFF;
unreffunc(cmdentry.u.func);
poplocalvars();
localvars = savelocalvars;
freeparam(&shellparam);
shellparam = saveparam;
handler = savehandler;
popredir();
INTON;
if (evalskip == SKIPFUNC) {
evalskip = 0;
skipcount = 0;
}
if (flags & EV_EXIT)
exitshell(exitstatus);
} else if (cmdentry.cmdtype == CMDBUILTIN) {
#ifdef DEBUG
trputs("builtin command: "); trargs(argv);
#endif
mode = (cmdentry.u.index == EXECCMD)? 0 : REDIR_PUSH;
if (flags == EV_BACKCMD) {
memout.nleft = 0;
memout.nextc = memout.buf;
memout.bufsize = 64;
mode |= REDIR_BACKQ;
}
savecmdname = commandname;
cmdenviron = varlist.list;
e = -1;
savehandler = handler;
if (setjmp(jmploc.loc)) {
e = exception;
exitstatus = (e == EXINT)? SIGINT+128 : 2;
goto cmddone;
}
handler = &jmploc;
redirect(cmd->ncmd.redirect, mode);
if (cmdentry.special)
listsetvar(cmdenviron);
commandname = argv[0];
argptr = argv + 1;
nextopt_optptr = NULL; /* initialize nextopt */
builtin_flags = flags;
exitstatus = (*builtinfunc[cmdentry.u.index])(argc, argv);
flushall();
cmddone:
cmdenviron = NULL;
out1 = &output;
out2 = &errout;
freestdout();
if (e != EXSHELLPROC) {
commandname = savecmdname;
if (flags & EV_EXIT) {
exitshell(exitstatus);
}
}
handler = savehandler;
if (e != -1) {
if ((e != EXERROR && e != EXEXEC)
|| cmdentry.special)
exraise(e);
FORCEINTON;
}
if (cmdentry.u.index != EXECCMD)
popredir();
if (flags == EV_BACKCMD) {
backcmd->buf = memout.buf;
backcmd->nleft = memout.nextc - memout.buf;
memout.buf = NULL;
}
} else {
#ifdef DEBUG
trputs("normal command: "); trargs(argv);
#endif
clearredir();
redirect(cmd->ncmd.redirect, 0);
for (sp = varlist.list ; sp ; sp = sp->next)
setvareq(sp->text, VEXPORT|VSTACK);
envp = environment();
shellexec(argv, envp, pathval(), cmdentry.u.index);
/*NOTREACHED*/
}
goto out;
parent: /* parent process gets here (if we forked) */
if (mode == FORK_FG) { /* argument to fork */
INTOFF;
exitstatus = waitforjob(jp, &realstatus);
INTON;
if (iflag && loopnest > 0 && WIFSIGNALED(realstatus)) {
evalskip = SKIPBREAK;
skipcount = loopnest;
}
} else if (mode == FORK_NOJOB) {
backcmd->fd = pip[0];
close(pip[1]);
backcmd->jp = jp;
}
out:
if (lastarg)
setvar("_", lastarg, 0);
if (do_clearcmdentry)
clearcmdentry(0);
popstackmark(&smark);
}
void
evaltree(union node *n, int flags)
{
int do_etest;
do_etest = 0;
if (n == NULL) {
TRACE(("evaltree(NULL) called\n"));
exitstatus = 0;
goto out;
}
#ifndef NO_HISTORY
displayhist = 1; /* show history substitutions done with fc */
#endif
TRACE(("evaltree(%p: %d) called\n", (void *)n, n->type));
switch (n->type) {
case NSEMI:
evaltree(n->nbinary.ch1, flags & ~EV_EXIT);
if (evalskip)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NAND:
evaltree(n->nbinary.ch1, EV_TESTED);
if (evalskip || exitstatus != 0) {
goto out;
}
evaltree(n->nbinary.ch2, flags);
break;
case NOR:
evaltree(n->nbinary.ch1, EV_TESTED);
if (evalskip || exitstatus == 0)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NREDIR:
oexitstatus = exitstatus;
expredir(n->nredir.redirect);
redirect(n->nredir.redirect, REDIR_PUSH);
evaltree(n->nredir.n, flags);
popredir();
break;
case NSUBSHELL:
evalsubshell(n, flags);
do_etest = !(flags & EV_TESTED);
break;
case NBACKGND:
evalsubshell(n, flags);
break;
case NIF: {
evaltree(n->nif.test, EV_TESTED);
if (evalskip)
goto out;
if (exitstatus == 0)
evaltree(n->nif.ifpart, flags);
else if (n->nif.elsepart)
evaltree(n->nif.elsepart, flags);
else
exitstatus = 0;
break;
}
case NWHILE:
case NUNTIL:
evalloop(n, flags & ~EV_EXIT);
break;
case NFOR:
evalfor(n, flags & ~EV_EXIT);
break;
case NCASE:
evalcase(n, flags);
break;
case NDEFUN:
defun(n->narg.text, n->narg.next);
exitstatus = 0;
break;
case NNOT:
evaltree(n->nnot.com, EV_TESTED);
exitstatus = !exitstatus;
break;
case NPIPE:
evalpipe(n);
do_etest = !(flags & EV_TESTED);
break;
case NCMD:
evalcommand(n, flags, (struct backcmd *)NULL);
do_etest = !(flags & EV_TESTED);
break;
default:
out1fmt("Node type = %d\n", n->type);
flushout(&output);
break;
}
out:
if (pendingsigs)
dotrap();
if ((flags & EV_EXIT) || (eflag && exitstatus != 0 && do_etest))
exitshell(exitstatus);
}
STATIC void
evalcommand(shinstance *psh, union node *cmd, int flags, struct backcmd *backcmd)
{
struct stackmark smark;
union node *argp;
struct arglist arglist;
struct arglist varlist;
char **argv;
int argc;
char **envp;
int varflag;
struct strlist *sp;
int mode;
int pip[2];
struct cmdentry cmdentry;
struct job *jp;
struct jmploc jmploc;
struct jmploc *volatile savehandler;
char *volatile savecmdname;
volatile struct shparam saveparam;
struct localvar *volatile savelocalvars;
volatile int e;
char *lastarg;
const char *path = pathval(psh);
volatile int temp_path;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &argv;
(void) &argc;
(void) &lastarg;
(void) &flags;
#endif
psh->vforked = 0;
/* First expand the arguments. */
TRACE((psh, "evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
setstackmark(psh, &smark);
psh->back_exitstatus = 0;
arglist.lastp = &arglist.list;
varflag = 1;
/* Expand arguments, ignoring the initial 'name=value' ones */
for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
char *p = argp->narg.text;
if (varflag && is_name(*p)) {
do {
p++;
} while (is_in_name(*p));
if (*p == '=')
continue;
}
expandarg(psh, argp, &arglist, EXP_FULL | EXP_TILDE);
varflag = 0;
}
*arglist.lastp = NULL;
expredir(psh, cmd->ncmd.redirect);
/* Now do the initial 'name=value' ones we skipped above */
varlist.lastp = &varlist.list;
for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
char *p = argp->narg.text;
if (!is_name(*p))
break;
do
p++;
while (is_in_name(*p));
if (*p != '=')
break;
expandarg(psh, argp, &varlist, EXP_VARTILDE);
}
*varlist.lastp = NULL;
argc = 0;
for (sp = arglist.list ; sp ; sp = sp->next)
argc++;
argv = stalloc(psh, sizeof (char *) * (argc + 1));
for (sp = arglist.list ; sp ; sp = sp->next) {
TRACE((psh, "evalcommand arg: %s\n", sp->text));
*argv++ = sp->text;
}
*argv = NULL;
lastarg = NULL;
if (iflag(psh) && psh->funcnest == 0 && argc > 0)
lastarg = argv[-1];
argv -= argc;
/* Print the command if xflag is set. */
if (xflag(psh)) {
char sep = 0;
out2str(psh, ps4val(psh));
for (sp = varlist.list ; sp ; sp = sp->next) {
if (sep != 0)
outc(sep, &psh->errout);
out2str(psh, sp->text);
sep = ' ';
}
for (sp = arglist.list ; sp ; sp = sp->next) {
if (sep != 0)
outc(sep, &psh->errout);
out2str(psh, sp->text);
sep = ' ';
}
outc('\n', &psh->errout);
flushout(&psh->errout);
}
/* Now locate the command. */
if (argc == 0) {
cmdentry.cmdtype = CMDSPLBLTIN;
cmdentry.u.bltin = bltincmd;
} else {
static const char PATH[] = "PATH=";
int cmd_flags = DO_ERR;
/*
* Modify the command lookup path, if a PATH= assignment
* is present
*/
for (sp = varlist.list; sp; sp = sp->next)
if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0)
path = sp->text + sizeof(PATH) - 1;
do {
int argsused, use_syspath;
find_command(psh, argv[0], &cmdentry, cmd_flags, path);
if (cmdentry.cmdtype == CMDUNKNOWN) {
psh->exitstatus = 127;
flushout(&psh->errout);
goto out;
}
/* implement the 'command' builtin here */
if (cmdentry.cmdtype != CMDBUILTIN ||
cmdentry.u.bltin != bltincmd)
break;
cmd_flags |= DO_NOFUNC;
argsused = parse_command_args(psh, argc, argv, &use_syspath);
if (argsused == 0) {
/* use 'type' builting to display info */
cmdentry.u.bltin = typecmd;
break;
}
argc -= argsused;
argv += argsused;
if (use_syspath)
path = syspath(psh) + 5;
} while (argc != 0);
if (cmdentry.cmdtype == CMDSPLBLTIN && cmd_flags & DO_NOFUNC)
/* posix mandates that 'command <splbltin>' act as if
<splbltin> was a normal builtin */
cmdentry.cmdtype = CMDBUILTIN;
}
/* Fork off a child process if necessary. */
if (cmd->ncmd.backgnd
|| (cmdentry.cmdtype == CMDNORMAL && (flags & EV_EXIT) == 0)
|| ((flags & EV_BACKCMD) != 0
&& ((cmdentry.cmdtype != CMDBUILTIN && cmdentry.cmdtype != CMDSPLBLTIN)
|| cmdentry.u.bltin == dotcmd
|| cmdentry.u.bltin == evalcmd))) {
INTOFF;
jp = makejob(psh, cmd, 1);
mode = cmd->ncmd.backgnd;
if (flags & EV_BACKCMD) {
mode = FORK_NOJOB;
if (sh_pipe(psh, pip) < 0)
error(psh, "Pipe call failed");
}
#ifdef DO_SHAREDVFORK
/* It is essential that if DO_SHAREDVFORK is defined that the
* child's address space is actually shared with the parent as
* we rely on this.
*/
if (cmdentry.cmdtype == CMDNORMAL) {
pid_t pid;
savelocalvars = psh->localvars;
psh->localvars = NULL;
psh->vforked = 1;
switch (pid = vfork()) {
case -1:
TRACE((psh, "Vfork failed, errno=%d\n", errno));
INTON;
error(psh, "Cannot vfork");
break;
case 0:
/* Make sure that exceptions only unwind to
* after the vfork(2)
*/
if (setjmp(jmploc.loc)) {
if (psh->exception == EXSHELLPROC) {
/* We can't progress with the vfork,
* so, set vforked = 2 so the parent
* knows, and _exit();
*/
psh->vforked = 2;
sh__exit(psh, 0);
} else {
sh__exit(psh, psh->exerrno);
}
}
savehandler = psh->handler;
psh->handler = &jmploc;
listmklocal(psh, varlist.list, VEXPORT | VNOFUNC);
forkchild(psh, jp, cmd, mode, psh->vforked);
break;
default:
psh->handler = savehandler; /* restore from vfork(2) */
poplocalvars(psh);
psh->localvars = savelocalvars;
if (psh->vforked == 2) {
psh->vforked = 0;
(void)sh_waitpid(psh, pid, NULL, 0);
/* We need to progress in a normal fork fashion */
goto normal_fork;
}
psh->vforked = 0;
forkparent(psh, jp, cmd, mode, pid);
goto parent;
}
} else {
normal_fork:
#endif
if (forkshell(psh, jp, cmd, mode) != 0)
goto parent; /* at end of routine */
FORCEINTON;
#ifdef DO_SHAREDVFORK
}
#endif
if (flags & EV_BACKCMD) {
if (!psh->vforked) {
FORCEINTON;
}
shfile_close(&psh->fdtab, pip[0]);
if (pip[1] != 1) {
movefd(psh, pip[1], 1);
}
}
flags |= EV_EXIT;
}
/* This is the child process if a fork occurred. */
/* Execute the command. */
switch (cmdentry.cmdtype) {
case CMDFUNCTION:
#ifdef DEBUG
trputs(psh, "Shell function: "); trargs(psh, argv);
#endif
redirect(psh, cmd->ncmd.redirect, REDIR_PUSH);
saveparam = psh->shellparam;
psh->shellparam.malloc = 0;
psh->shellparam.reset = 1;
psh->shellparam.nparam = argc - 1;
psh->shellparam.p = argv + 1;
psh->shellparam.optnext = NULL;
INTOFF;
savelocalvars = psh->localvars;
psh->localvars = NULL;
INTON;
if (setjmp(jmploc.loc)) {
if (psh->exception == EXSHELLPROC) {
freeparam(psh, (volatile struct shparam *)
&saveparam);
} else {
freeparam(psh, &psh->shellparam);
psh->shellparam = saveparam;
}
poplocalvars(psh);
psh->localvars = savelocalvars;
psh->handler = savehandler;
longjmp(psh->handler->loc, 1);
}
savehandler = psh->handler;
psh->handler = &jmploc;
listmklocal(psh, varlist.list, 0);
/* stop shell blowing its stack */
if (++psh->funcnest > 1000)
error(psh, "too many nested function calls");
evaltree(psh, cmdentry.u.func, flags & EV_TESTED);
psh->funcnest--;
INTOFF;
poplocalvars(psh);
psh->localvars = savelocalvars;
freeparam(psh, &psh->shellparam);
psh->shellparam = saveparam;
psh->handler = savehandler;
popredir(psh);
INTON;
if (psh->evalskip == SKIPFUNC) {
psh->evalskip = 0;
psh->skipcount = 0;
}
if (flags & EV_EXIT)
exitshell(psh, psh->exitstatus);
break;
case CMDBUILTIN:
case CMDSPLBLTIN:
#ifdef DEBUG
trputs(psh, "builtin command: "); trargs(psh, argv);
#endif
mode = (cmdentry.u.bltin == execcmd) ? 0 : REDIR_PUSH;
if (flags == EV_BACKCMD) {
psh->memout.nleft = 0;
psh->memout.nextc = psh->memout.buf;
psh->memout.bufsize = 64;
mode |= REDIR_BACKQ;
}
e = -1;
savehandler = psh->handler;
savecmdname = psh->commandname;
psh->handler = &jmploc;
if (!setjmp(jmploc.loc)) {
/* We need to ensure the command hash table isn't
* corruped by temporary PATH assignments.
* However we must ensure the 'local' command works!
*/
if (path != pathval(psh) && (cmdentry.u.bltin == hashcmd ||
cmdentry.u.bltin == typecmd)) {
savelocalvars = psh->localvars;
psh->localvars = 0;
mklocal(psh, path - 5 /* PATH= */, 0);
temp_path = 1;
} else
temp_path = 0;
redirect(psh, cmd->ncmd.redirect, mode);
/* exec is a special builtin, but needs this list... */
psh->cmdenviron = varlist.list;
/* we must check 'readonly' flag for all builtins */
listsetvar(psh, varlist.list,
cmdentry.cmdtype == CMDSPLBLTIN ? 0 : VNOSET);
psh->commandname = argv[0];
/* initialize nextopt */
psh->argptr = argv + 1;
psh->optptr = NULL;
/* and getopt */
#if 0 /** @todo fix getop usage! */
#if defined(__FreeBSD__) || defined(__EMX__) || defined(__APPLE__)
optreset = 1;
optind = 1;
#else
optind = 0; /* init */
#endif
#endif
psh->exitstatus = cmdentry.u.bltin(psh, argc, argv);
} else {
e = psh->exception;
psh->exitstatus = e == EXINT ? SIGINT + 128 :
e == EXEXEC ? psh->exerrno : 2;
}
psh->handler = savehandler;
output_flushall(psh);
psh->out1 = &psh->output;
psh->out2 = &psh->errout;
freestdout(psh);
if (temp_path) {
poplocalvars(psh);
psh->localvars = savelocalvars;
}
psh->cmdenviron = NULL;
if (e != EXSHELLPROC) {
psh->commandname = savecmdname;
if (flags & EV_EXIT)
exitshell(psh, psh->exitstatus);
}
if (e != -1) {
if ((e != EXERROR && e != EXEXEC)
|| cmdentry.cmdtype == CMDSPLBLTIN)
exraise(psh, e);
FORCEINTON;
}
if (cmdentry.u.bltin != execcmd)
popredir(psh);
if (flags == EV_BACKCMD) {
backcmd->buf = psh->memout.buf;
backcmd->nleft = (int)(psh->memout.nextc - psh->memout.buf);
psh->memout.buf = NULL;
}
break;
default:
#ifdef DEBUG
trputs(psh, "normal command: "); trargs(psh, argv);
#endif
clearredir(psh, psh->vforked);
redirect(psh, cmd->ncmd.redirect, psh->vforked ? REDIR_VFORK : 0);
if (!psh->vforked)
for (sp = varlist.list ; sp ; sp = sp->next)
setvareq(psh, sp->text, VEXPORT|VSTACK);
envp = environment(psh);
shellexec(psh, argv, envp, path, cmdentry.u.index, psh->vforked);
break;
}
goto out;
parent: /* parent process gets here (if we forked) */
if (mode == FORK_FG) { /* argument to fork */
psh->exitstatus = waitforjob(psh, jp);
} else if (mode == FORK_NOJOB) {
backcmd->fd = pip[0];
shfile_close(&psh->fdtab, pip[1]);
backcmd->jp = jp;
}
FORCEINTON;
out:
if (lastarg)
/* dsl: I think this is intended to be used to support
* '_' in 'vi' command mode during line editing...
* However I implemented that within libedit itself.
*/
setvar(psh, "_", lastarg, 0);
popstackmark(psh, &smark);
if (eflag(psh) && psh->exitstatus && !(flags & EV_TESTED))
exitshell(psh, psh->exitstatus);
}
void
evaltree(shinstance *psh, union node *n, int flags)
{
if (n == NULL) {
TRACE((psh, "evaltree(NULL) called\n"));
psh->exitstatus = 0;
goto out;
}
#ifndef SMALL
psh->displayhist = 1; /* show history substitutions done with fc */
#endif
TRACE((psh, "pid %d, evaltree(%p: %d, %d) called\n",
sh_getpid(psh), n, n->type, flags));
switch (n->type) {
case NSEMI:
evaltree(psh, n->nbinary.ch1, flags & EV_TESTED);
if (psh->evalskip)
goto out;
evaltree(psh, n->nbinary.ch2, flags);
break;
case NAND:
evaltree(psh, n->nbinary.ch1, EV_TESTED);
if (psh->evalskip || psh->exitstatus != 0)
goto out;
evaltree(psh, n->nbinary.ch2, flags);
break;
case NOR:
evaltree(psh, n->nbinary.ch1, EV_TESTED);
if (psh->evalskip || psh->exitstatus == 0)
goto out;
evaltree(psh, n->nbinary.ch2, flags);
break;
case NREDIR:
expredir(psh, n->nredir.redirect);
redirect(psh, n->nredir.redirect, REDIR_PUSH);
evaltree(psh, n->nredir.n, flags);
popredir(psh);
break;
case NSUBSHELL:
evalsubshell(psh, n, flags);
break;
case NBACKGND:
evalsubshell(psh, n, flags);
break;
case NIF: {
evaltree(psh, n->nif.test, EV_TESTED);
if (psh->evalskip)
goto out;
if (psh->exitstatus == 0)
evaltree(psh, n->nif.ifpart, flags);
else if (n->nif.elsepart)
evaltree(psh, n->nif.elsepart, flags);
else
psh->exitstatus = 0;
break;
}
case NWHILE:
case NUNTIL:
evalloop(psh, n, flags);
break;
case NFOR:
evalfor(psh, n, flags);
break;
case NCASE:
evalcase(psh, n, flags);
break;
case NDEFUN:
defun(psh, n->narg.text, n->narg.next);
psh->exitstatus = 0;
break;
case NNOT:
evaltree(psh, n->nnot.com, EV_TESTED);
psh->exitstatus = !psh->exitstatus;
break;
case NPIPE:
evalpipe(psh, n);
break;
case NCMD:
evalcommand(psh, n, flags, (struct backcmd *)NULL);
break;
default:
out1fmt(psh, "Node type = %d\n", n->type);
flushout(&psh->output);
break;
}
out:
if (psh->pendingsigs)
dotrap(psh);
if ((flags & EV_EXIT) != 0)
exitshell(psh, psh->exitstatus);
}
void
evaltree(union node *n, int flags)
{
bool do_etest;
do_etest = false;
if (n == NULL || nflag) {
TRACE(("evaltree(%s) called\n", n == NULL ? "NULL" : "-n"));
if (nflag == 0)
exitstatus = 0;
goto out;
}
#ifndef SMALL
displayhist = 1; /* show history substitutions done with fc */
#endif
#ifdef NODETYPENAME
TRACE(("pid %d, evaltree(%p: %s(%d), %#x) called\n",
getpid(), n, NODETYPENAME(n->type), n->type, flags));
#else
TRACE(("pid %d, evaltree(%p: %d, %#x) called\n",
getpid(), n, n->type, flags));
#endif
switch (n->type) {
case NSEMI:
evaltree(n->nbinary.ch1, flags & EV_TESTED);
if (nflag || evalskip)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NAND:
evaltree(n->nbinary.ch1, EV_TESTED);
if (nflag || evalskip || exitstatus != 0)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NOR:
evaltree(n->nbinary.ch1, EV_TESTED);
if (nflag || evalskip || exitstatus == 0)
goto out;
evaltree(n->nbinary.ch2, flags);
break;
case NREDIR:
expredir(n->nredir.redirect);
redirect(n->nredir.redirect, REDIR_PUSH | REDIR_KEEP);
evaltree(n->nredir.n, flags);
popredir();
break;
case NSUBSHELL:
evalsubshell(n, flags);
do_etest = !(flags & EV_TESTED);
break;
case NBACKGND:
evalsubshell(n, flags);
break;
case NIF: {
evaltree(n->nif.test, EV_TESTED);
if (nflag || evalskip)
goto out;
if (exitstatus == 0)
evaltree(n->nif.ifpart, flags);
else if (n->nif.elsepart)
evaltree(n->nif.elsepart, flags);
else
exitstatus = 0;
break;
}
case NWHILE:
case NUNTIL:
evalloop(n, flags);
break;
case NFOR:
evalfor(n, flags);
break;
case NCASE:
evalcase(n, flags);
break;
case NDEFUN:
defun(n->narg.text, n->narg.next);
exitstatus = 0;
break;
case NNOT:
evaltree(n->nnot.com, EV_TESTED);
exitstatus = !exitstatus;
break;
case NPIPE:
evalpipe(n);
do_etest = !(flags & EV_TESTED);
break;
case NCMD:
evalcommand(n, flags, NULL);
do_etest = !(flags & EV_TESTED);
break;
default:
#ifdef NODETYPENAME
out1fmt("Node type = %d(%s)\n", n->type, NODETYPENAME(n->type));
#else
out1fmt("Node type = %d\n", n->type);
#endif
flushout(&output);
break;
}
out:
if (pendingsigs)
dotrap();
if ((flags & EV_EXIT) != 0 || (eflag && exitstatus != 0 && do_etest))
exitshell(exitstatus);
}
