/* Used to calculate an array index for global()/local(). Sets *arrayp to
* non-zero if this is an array, sets *valp to the array index, returns
* the basename of the array.
*/
static const char *
array_index_calc(const char *n, bool *arrayp, int *valp)
{
const char *p;
int len;
*arrayp = false;
p = skip_varname(n, false);
if (p != n && *p == '[' && (len = array_ref_len(p))) {
char *sub, *tmp;
long rval;
/* Calculate the value of the subscript */
*arrayp = true;
tmp = str_nsave(p+1, len-2, ATEMP);
sub = substitute(tmp, 0);
afree(tmp, ATEMP);
n = str_nsave(n, p - n, ATEMP);
evaluate(sub, &rval, KSH_UNWIND_ERROR, true);
if (rval < 0 || rval > ARRAYMAX)
errorf("%s: subscript %ld out of range", n, rval);
*valp = rval;
afree(sub, ATEMP);
}
return n;
}
/*
* Return a pointer to the first char past a legal variable name
* (returns the argument if there is no legal name, returns a pointer to
* the terminating NUL if whole string is legal).
*/
const char *
skip_varname(const char *s, bool aok)
{
size_t alen;
if (s && ksh_isalphx(*s)) {
while (*++s && ksh_isalnux(*s))
;
if (aok && *s == '[' && (alen = array_ref_len(s)))
s += alen;
}
return (s);
}
/*
* Return a pointer to the first char past a legal variable name
* (returns the argument if there is no legal name, returns a pointer to
* the terminating NUL if whole string is legal).
*/
const char *
skip_varname(const char *s, bool aok)
{
size_t alen;
if (s && ctype(*s, C_ALPHX)) {
do {
++s;
} while (ctype(*s, C_ALNUX));
if (aok && ord(*s) == ord('[') && (alen = array_ref_len(s)))
s += alen;
}
return (s);
}
/*
* Used to calculate an array index for global()/local(). Sets *arrayp
* to true if this is an array, sets *valp to the array index, returns
* the basename of the array. May only be called from global()/local()
* and must be their first callee.
*/
static const char *
array_index_calc(const char *n, bool *arrayp, uint32_t *valp)
{
const char *p;
size_t len;
char *ap = NULL;
*arrayp = false;
redo_from_ref:
p = skip_varname(n, false);
if (innermost_refflag == SRF_NOP && (p != n) && ksh_isalphx(n[0])) {
struct tbl *vp;
char *vn;
strndupx(vn, n, p - n, ATEMP);
/* check if this is a reference */
varsearch(e->loc, &vp, vn, hash(vn));
afree(vn, ATEMP);
if (vp && (vp->flag & (DEFINED | ASSOC | ARRAY)) ==
(DEFINED | ASSOC)) {
char *cp;
/* gotcha! */
cp = shf_smprintf("%s%s", str_val(vp), p);
afree(ap, ATEMP);
n = ap = cp;
goto redo_from_ref;
}
}
innermost_refflag = SRF_NOP;
if (p != n && *p == '[' && (len = array_ref_len(p))) {
char *sub, *tmp;
mksh_ari_t rval;
/* calculate the value of the subscript */
*arrayp = true;
strndupx(tmp, p + 1, len - 2, ATEMP);
sub = substitute(tmp, 0);
afree(tmp, ATEMP);
strndupx(n, n, p - n, ATEMP);
evaluate(sub, &rval, KSH_UNWIND_ERROR, true);
*valp = (uint32_t)rval;
afree(sub, ATEMP);
}
return (n);
}
/*
* 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);
}