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();
}
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);
}
