void
yyerror(const char *fmt, ...)
{
va_list va;
/* pop aliases and re-reads */
while (source->type == SALIAS || source->type == SREREAD)
source = source->next;
/* zap pending input */
source->str = null;
error_prefix(true);
va_start(va, fmt);
shf_vfprintf(shl_out, fmt, va);
va_end(va);
errorfz();
}
/*
* execute command tree
*/
int
execute(struct op * volatile t,
/* if XEXEC don't fork */
volatile int flags,
volatile int * volatile xerrok)
{
int i;
volatile int rv = 0, dummy = 0;
int pv[2];
const char ** volatile ap = NULL;
char ** volatile up;
const char *s, *ccp;
struct ioword **iowp;
struct tbl *tp = NULL;
char *cp;
if (t == NULL)
return (0);
/* Caller doesn't care if XERROK should propagate. */
if (xerrok == NULL)
xerrok = &dummy;
if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
/* run in sub-process */
return (exchild(t, flags & ~XTIME, xerrok, -1));
newenv(E_EXEC);
if (trap)
runtraps(0);
/* we want to run an executable, do some variance checks */
if (t->type == TCOM) {
/* check if this is 'var=<<EOF' */
if (
/* we have zero arguments, i.e. no programme to run */
t->args[0] == NULL &&
/* we have exactly one variable assignment */
t->vars[0] != NULL && t->vars[1] == NULL &&
/* we have exactly one I/O redirection */
t->ioact != NULL && t->ioact[0] != NULL &&
t->ioact[1] == NULL &&
/* of type "here document" (or "here string") */
(t->ioact[0]->flag & IOTYPE) == IOHERE &&
/* the variable assignment begins with a valid varname */
(ccp = skip_wdvarname(t->vars[0], true)) != t->vars[0] &&
/* and has no right-hand side (i.e. "varname=") */
ccp[0] == CHAR && ccp[1] == '=' && ccp[2] == EOS &&
/* plus we can have a here document content */
herein(t->ioact[0], &cp) == 0 && cp && *cp) {
char *sp = cp, *dp;
size_t n = ccp - t->vars[0] + 2, z;
/* drop redirection (will be garbage collected) */
t->ioact = NULL;
/* set variable to its expanded value */
z = strlen(cp) + 1;
if (notoktomul(z, 2) || notoktoadd(z * 2, n))
internal_errorf(Toomem, (unsigned long)-1);
dp = alloc(z * 2 + n, ATEMP);
memcpy(dp, t->vars[0], n);
t->vars[0] = dp;
dp += n;
while (*sp) {
*dp++ = QCHAR;
*dp++ = *sp++;
}
*dp = EOS;
/* free the expanded value */
afree(cp, APERM);
}
/*
* Clear subst_exstat before argument expansion. Used by
* null commands (see comexec() and c_eval()) and by c_set().
*/
subst_exstat = 0;
/* for $LINENO */
current_lineno = t->lineno;
/*
* POSIX says expand command words first, then redirections,
* and assignments last..
*/
up = eval(t->args, t->u.evalflags | DOBLANK | DOGLOB | DOTILDE);
if (flags & XTIME)
/* Allow option parsing (bizarre, but POSIX) */
timex_hook(t, &up);
ap = (const char **)up;
if (Flag(FXTRACE) && ap[0]) {
shf_puts(substitute(str_val(global("PS4")), 0),
shl_out);
for (i = 0; ap[i]; i++)
shf_fprintf(shl_out, "%s%c", ap[i],
ap[i + 1] ? ' ' : '\n');
shf_flush(shl_out);
}
if (ap[0])
tp = findcom(ap[0], FC_BI|FC_FUNC);
}
flags &= ~XTIME;
if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
e->savefd = alloc2(NUFILE, sizeof(short), ATEMP);
/* initialise to not redirected */
memset(e->savefd, 0, NUFILE * sizeof(short));
}
/* mark for replacement later (unless TPIPE) */
vp_pipest->flag |= INT_L;
/* do redirection, to be restored in quitenv() */
if (t->ioact != NULL)
for (iowp = t->ioact; *iowp != NULL; iowp++) {
if (iosetup(*iowp, tp) < 0) {
exstat = rv = 1;
/*
* Redirection failures for special commands
* cause (non-interactive) shell to exit.
*/
if (tp && tp->type == CSHELL &&
(tp->flag & SPEC_BI))
errorfz();
/* Deal with FERREXIT, quitenv(), etc. */
goto Break;
}
}
switch (t->type) {
case TCOM:
rv = comexec(t, tp, (const char **)ap, flags, xerrok);
break;
case TPAREN:
rv = execute(t->left, flags | XFORK, xerrok);
break;
case TPIPE:
flags |= XFORK;
flags &= ~XEXEC;
e->savefd[0] = savefd(0);
e->savefd[1] = savefd(1);
while (t->type == TPIPE) {
openpipe(pv);
/* stdout of curr */
ksh_dup2(pv[1], 1, false);
/**
* Let exchild() close pv[0] in child
* (if this isn't done, commands like
* (: ; cat /etc/termcap) | sleep 1
* will hang forever).
*/
exchild(t->left, flags | XPIPEO | XCCLOSE,
NULL, pv[0]);
/* stdin of next */
ksh_dup2(pv[0], 0, false);
closepipe(pv);
flags |= XPIPEI;
t = t->right;
}
/* stdout of last */
restfd(1, e->savefd[1]);
/* no need to re-restore this */
e->savefd[1] = 0;
/* Let exchild() close 0 in parent, after fork, before wait */
i = exchild(t, flags | XPCLOSE | XPIPEST, xerrok, 0);
if (!(flags&XBGND) && !(flags&XXCOM))
rv = i;
break;
case TLIST:
while (t->type == TLIST) {
execute(t->left, flags & XERROK, NULL);
t = t->right;
}
rv = execute(t, flags & XERROK, xerrok);
break;
case TCOPROC: {
#ifndef MKSH_NOPROSPECTOFWORK
sigset_t omask;
/*
* Block sigchild as we are using things changed in the
* signal handler
*/
sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
e->type = E_ERRH;
if ((i = kshsetjmp(e->jbuf))) {
sigprocmask(SIG_SETMASK, &omask, NULL);
quitenv(NULL);
unwind(i);
/* NOTREACHED */
}
#endif
/* Already have a (live) co-process? */
if (coproc.job && coproc.write >= 0)
errorf("coprocess already exists");
/* Can we re-use the existing co-process pipe? */
coproc_cleanup(true);
/* do this before opening pipes, in case these fail */
e->savefd[0] = savefd(0);
e->savefd[1] = savefd(1);
openpipe(pv);
if (pv[0] != 0) {
ksh_dup2(pv[0], 0, false);
close(pv[0]);
}
coproc.write = pv[1];
coproc.job = NULL;
if (coproc.readw >= 0)
ksh_dup2(coproc.readw, 1, false);
else {
openpipe(pv);
coproc.read = pv[0];
ksh_dup2(pv[1], 1, false);
/* closed before first read */
coproc.readw = pv[1];
coproc.njobs = 0;
/* create new coprocess id */
++coproc.id;
}
#ifndef MKSH_NOPROSPECTOFWORK
sigprocmask(SIG_SETMASK, &omask, NULL);
/* no more need for error handler */
e->type = E_EXEC;
#endif
/*
* exchild() closes coproc.* in child after fork,
* will also increment coproc.njobs when the
* job is actually created.
*/
flags &= ~XEXEC;
exchild(t->left, flags | XBGND | XFORK | XCOPROC | XCCLOSE,
NULL, coproc.readw);
break;
}
case TASYNC:
/*
* XXX non-optimal, I think - "(foo &)", forks for (),
* forks again for async... parent should optimise
* this to "foo &"...
*/
rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK, xerrok);
break;
case TOR:
case TAND:
rv = execute(t->left, XERROK, xerrok);
if ((rv == 0) == (t->type == TAND))
rv = execute(t->right, XERROK, xerrok);
flags |= XERROK;
if (xerrok)
*xerrok = 1;
break;
case TBANG:
rv = !execute(t->right, XERROK, xerrok);
flags |= XERROK;
if (xerrok)
*xerrok = 1;
break;
case TDBRACKET: {
Test_env te;
te.flags = TEF_DBRACKET;
te.pos.wp = t->args;
te.isa = dbteste_isa;
te.getopnd = dbteste_getopnd;
te.eval = test_eval;
te.error = dbteste_error;
rv = test_parse(&te);
break;
}
case TFOR:
case TSELECT: {
volatile bool is_first = true;
ap = (t->vars == NULL) ? e->loc->argv + 1 :
(const char **)eval((const char **)t->vars,
DOBLANK | DOGLOB | DOTILDE);
e->type = E_LOOP;
while ((i = kshsetjmp(e->jbuf))) {
if ((e->flags&EF_BRKCONT_PASS) ||
(i != LBREAK && i != LCONTIN)) {
quitenv(NULL);
unwind(i);
} else if (i == LBREAK) {
rv = 0;
goto Break;
}
}
/* in case of a continue */
rv = 0;
if (t->type == TFOR) {
while (*ap != NULL) {
setstr(global(t->str), *ap++, KSH_UNWIND_ERROR);
rv = execute(t->left, flags & XERROK, xerrok);
}
} else {
/* TSELECT */
for (;;) {
if (!(ccp = do_selectargs(ap, is_first))) {
rv = 1;
break;
}
is_first = false;
setstr(global(t->str), ccp, KSH_UNWIND_ERROR);
execute(t->left, flags & XERROK, xerrok);
}
}
break;
}
case TWHILE:
case TUNTIL:
e->type = E_LOOP;
while ((i = kshsetjmp(e->jbuf))) {
if ((e->flags&EF_BRKCONT_PASS) ||
(i != LBREAK && i != LCONTIN)) {
quitenv(NULL);
unwind(i);
} else if (i == LBREAK) {
rv = 0;
goto Break;
}
}
/* in case of a continue */
rv = 0;
while ((execute(t->left, XERROK, NULL) == 0) ==
(t->type == TWHILE))
rv = execute(t->right, flags & XERROK, xerrok);
break;
case TIF:
case TELIF:
if (t->right == NULL)
/* should be error */
break;
rv = execute(t->left, XERROK, NULL) == 0 ?
execute(t->right->left, flags & XERROK, xerrok) :
execute(t->right->right, flags & XERROK, xerrok);
break;
case TCASE:
i = 0;
ccp = evalstr(t->str, DOTILDE);
for (t = t->left; t != NULL && t->type == TPAT; t = t->right) {
for (ap = (const char **)t->vars; *ap; ap++) {
if (i || ((s = evalstr(*ap, DOTILDE|DOPAT)) &&
gmatchx(ccp, s, false))) {
rv = execute(t->left, flags & XERROK,
xerrok);
i = 0;
switch (t->u.charflag) {
case '&':
i = 1;
/* FALLTHROUGH */
case '|':
goto TCASE_next;
}
goto TCASE_out;
}
}
i = 0;
TCASE_next:
/* empty */;
}
TCASE_out:
break;
case TBRACE:
rv = execute(t->left, flags & XERROK, xerrok);
break;
case TFUNCT:
rv = define(t->str, t);
break;
case TTIME:
/*
* Clear XEXEC so nested execute() call doesn't exit
* (allows "ls -l | time grep foo").
*/
rv = timex(t, flags & ~XEXEC, xerrok);
break;
case TEXEC:
/* an eval'd TCOM */
s = t->args[0];
up = makenv();
restoresigs();
cleanup_proc_env();
{
union mksh_ccphack cargs;
cargs.ro = t->args;
execve(t->str, cargs.rw, up);
rv = errno;
}
if (rv == ENOEXEC)
scriptexec(t, (const char **)up);
else
errorf("%s: %s", s, cstrerror(rv));
}
Break:
exstat = rv & 0xFF;
if (vp_pipest->flag & INT_L) {
unset(vp_pipest, 1);
vp_pipest->flag = DEFINED | ISSET | INTEGER | RDONLY |
ARRAY | INT_U;
vp_pipest->val.i = rv;
}
/* restores IO */
quitenv(NULL);
if ((flags&XEXEC))
/* exit child */
unwind(LEXIT);
if (rv != 0 && !(flags & XERROK) &&
(xerrok == NULL || !*xerrok)) {
if (Flag(FERREXIT) & 0x80) {
/* inside eval */
Flag(FERREXIT) = 0;
} else {
trapsig(ksh_SIGERR);
if (Flag(FERREXIT))
unwind(LERROR);
}
}
return (rv);
}
/*
* lookup variable (according to (set&LOCAL)), set its attributes
* (INTEGER, RDONLY, EXPORT, TRACE, LJUST, RJUST, ZEROFIL, LCASEV,
* UCASEV_AL), and optionally set its value if an assignment.
*/
struct tbl *
typeset(const char *var, uint32_t set, uint32_t clr, int field, int base)
{
struct tbl *vp;
struct tbl *vpbase, *t;
char *tvar;
const char *val;
size_t len;
bool vappend = false;
enum namerefflag new_refflag = SRF_NOP;
if ((set & (ARRAY | ASSOC)) == ASSOC) {
new_refflag = SRF_ENABLE;
set &= ~(ARRAY | ASSOC);
}
if ((clr & (ARRAY | ASSOC)) == ASSOC) {
new_refflag = SRF_DISABLE;
clr &= ~(ARRAY | ASSOC);
}
/* check for valid variable name, search for value */
val = skip_varname(var, false);
if (val == var) {
/* no variable name given */
return (NULL);
}
if (*val == '[') {
if (new_refflag != SRF_NOP)
errorf("%s: %s", var,
"reference variable can't be an array");
len = array_ref_len(val);
if (len == 0)
return (NULL);
/*
* IMPORT is only used when the shell starts up and is
* setting up its environment. Allow only simple array
* references at this time since parameter/command
* substitution is performed on the [expression] which
* would be a major security hole.
*/
if (set & IMPORT) {
size_t i;
for (i = 1; i < len - 1; i++)
if (!ksh_isdigit(val[i]))
return (NULL);
}
val += len;
}
if (val[0] == '=') {
strndupx(tvar, var, val - var, ATEMP);
++val;
} else if (set & IMPORT) {
/* environment invalid variable name or no assignment */
return (NULL);
} else if (val[0] == '+' && val[1] == '=') {
strndupx(tvar, var, val - var, ATEMP);
val += 2;
vappend = true;
} else if (val[0] != '\0') {
/* other invalid variable names (not from environment) */
return (NULL);
} else {
/* just varname with no value part nor equals sign */
strdupx(tvar, var, ATEMP);
val = NULL;
/* handle foo[*] => foo (whole array) mapping for R39b */
len = strlen(tvar);
if (len > 3 && tvar[len - 3] == '[' && tvar[len - 2] == '*' &&
tvar[len - 1] == ']')
tvar[len - 3] = '\0';
}
if (new_refflag == SRF_ENABLE) {
const char *qval, *ccp;
/* bail out on 'nameref foo+=bar' */
if (vappend)
errorf("appending not allowed for nameref");
/* find value if variable already exists */
if ((qval = val) == NULL) {
varsearch(e->loc, &vp, tvar, hash(tvar));
if (vp == NULL)
goto nameref_empty;
qval = str_val(vp);
}
/* check target value for being a valid variable name */
ccp = skip_varname(qval, false);
if (ccp == qval) {
if (ksh_isdigit(qval[0])) {
int c;
if (getn(qval, &c))
goto nameref_rhs_checked;
} else if (qval[1] == '\0') switch (qval[0]) {
case '$':
case '!':
case '?':
case '#':
case '-':
goto nameref_rhs_checked;
}
nameref_empty:
errorf("%s: %s", var, "empty nameref target");
}
len = (*ccp == '[') ? array_ref_len(ccp) : 0;
if (ccp[len]) {
/*
* works for cases "no array", "valid array with
* junk after it" and "invalid array"; in the
* latter case, len is also 0 and points to '['
*/
errorf("%s: %s", qval,
"nameref target not a valid parameter name");
}
nameref_rhs_checked:
/* prevent nameref loops */
while (qval) {
if (!strcmp(qval, tvar))
errorf("%s: %s", qval,
"expression recurses on parameter");
varsearch(e->loc, &vp, qval, hash(qval));
qval = NULL;
if (vp && ((vp->flag & (ARRAY | ASSOC)) == ASSOC))
qval = str_val(vp);
}
}
/* prevent typeset from creating a local PATH/ENV/SHELL */
if (Flag(FRESTRICTED) && (strcmp(tvar, "PATH") == 0 ||
strcmp(tvar, "ENV") == 0 || strcmp(tvar, "SHELL") == 0))
errorf("%s: %s", tvar, "restricted");
innermost_refflag = new_refflag;
vp = (set & LOCAL) ? local(tvar, tobool(set & LOCAL_COPY)) :
global(tvar);
if (new_refflag == SRF_DISABLE && (vp->flag & (ARRAY|ASSOC)) == ASSOC)
vp->flag &= ~ASSOC;
else if (new_refflag == SRF_ENABLE) {
if (vp->flag & ARRAY) {
struct tbl *a, *tmp;
/* free up entire array */
for (a = vp->u.array; a; ) {
tmp = a;
a = a->u.array;
if (tmp->flag & ALLOC)
afree(tmp->val.s, tmp->areap);
afree(tmp, tmp->areap);
}
vp->u.array = NULL;
vp->flag &= ~ARRAY;
}
vp->flag |= ASSOC;
}
set &= ~(LOCAL|LOCAL_COPY);
vpbase = (vp->flag & ARRAY) ? global(arrayname(tvar)) : vp;
/*
* only allow export flag to be set; AT&T ksh allows any
* attribute to be changed which means it can be truncated or
* modified (-L/-R/-Z/-i)
*/
if ((vpbase->flag & RDONLY) &&
(val || clr || (set & ~EXPORT)))
/* XXX check calls - is error here ok by POSIX? */
errorfx(2, "read-only: %s", tvar);
afree(tvar, ATEMP);
/* most calls are with set/clr == 0 */
if (set | clr) {
bool ok = true;
/*
* XXX if x[0] isn't set, there will be problems: need
* to have one copy of attributes for arrays...
*/
for (t = vpbase; t; t = t->u.array) {
bool fake_assign;
char *s = NULL;
char *free_me = NULL;
fake_assign = (t->flag & ISSET) && (!val || t != vp) &&
((set & (UCASEV_AL|LCASEV|LJUST|RJUST|ZEROFIL)) ||
((t->flag & INTEGER) && (clr & INTEGER)) ||
(!(t->flag & INTEGER) && (set & INTEGER)));
if (fake_assign) {
if (t->flag & INTEGER) {
s = str_val(t);
free_me = NULL;
} else {
s = t->val.s + t->type;
free_me = (t->flag & ALLOC) ? t->val.s :
NULL;
}
t->flag &= ~ALLOC;
}
if (!(t->flag & INTEGER) && (set & INTEGER)) {
t->type = 0;
t->flag &= ~ALLOC;
}
t->flag = (t->flag | set) & ~clr;
/*
* Don't change base if assignment is to be
* done, in case assignment fails.
*/
if ((set & INTEGER) && base > 0 && (!val || t != vp))
t->type = base;
if (set & (LJUST|RJUST|ZEROFIL))
t->u2.field = field;
if (fake_assign) {
if (!setstr(t, s, KSH_RETURN_ERROR)) {
/*
* Somewhat arbitrary action
* here: zap contents of
* variable, but keep the flag
* settings.
*/
ok = false;
if (t->flag & INTEGER)
t->flag &= ~ISSET;
else {
if (t->flag & ALLOC)
afree(t->val.s, t->areap);
t->flag &= ~(ISSET|ALLOC);
t->type = 0;
}
}
if (free_me)
afree(free_me, t->areap);
}
}
if (!ok)
errorfz();
}
if (val != NULL) {
char *tval;
if (vappend) {
tval = shf_smprintf("%s%s", str_val(vp), val);
val = tval;
} else
tval = NULL;
if (vp->flag&INTEGER) {
/* do not zero base before assignment */
setstr(vp, val, KSH_UNWIND_ERROR | 0x4);
/* done after assignment to override default */
if (base > 0)
vp->type = base;
} else
/* setstr can't fail (readonly check already done) */
setstr(vp, val, KSH_RETURN_ERROR | 0x4);
if (tval != NULL)
afree(tval, ATEMP);
}
/* only x[0] is ever exported, so use vpbase */
if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER) &&
vpbase->type == 0)
exportprep(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null);
return (vp);
}
