static intstar4 CheckSubStr( act_eq_entry *eqv_entry ) {
//==============================================================
// Check for a valid substring operation.
sym_id sym;
intstar4 *substr;
intstar4 offset;
intstar4 last;
sym = eqv_entry->name_equived;
substr = &eqv_entry->subscrs[ eqv_entry->subs_no ];
if( sym->ns.typ != TY_CHAR ) {
NameTypeErr( EV_ONLY_IF_CHAR, sym );
offset = 0;
} else {
offset = substr[0];
if( eqv_entry->substr == 1 ) {
last = sym->ns.xt.size;
} else {
last = substr[1];
}
if( DoSubstring( offset, last, sym->ns.xt.size ) ) {
offset--;
} else {
NameStmtErr( EV_SSTR_INVALID, sym, PR_EQUIV );
offset = 0;
}
}
return( offset );
}
void DtFieldSubstring( void ) {
//==========================
// Data initialize a substring character item within a structure.
sym_id fd;
intstar4 base;
intstar4 first;
intstar4 last;
char name[MAX_SYMLEN+1];
base = DXPop();
first = DXPop();
fd = GetPtr();
last = GetInt();
if( last != 0 ) {
last += first - 1;
} else {
last = DXPop();
}
GetU16(); // skip typing information
if( DoSubstring( first, last, fd->u.fd.xt.size ) ) {
DXPush( base + first - 1 );
DtItemSize = last - first + 1;
} else {
STFieldName( fd, name );
Error( EV_SSTR_INVALID, name, StmtKeywords[ PR_DATA ] );
}
}
void DtSubstring( void ) {
//=====================
// Data initialize a character substring.
intstar4 first;
intstar4 last;
sym_id cv;
cv = GetPtr();
GetU16(); // skip typing information
first = DXPop();
if( cv != NULL ) {
if( DtFlags & DT_SS_NO_HIGH ) {
last = cv->u.ns.xt.size;
DtFlags &= ~DT_SS_NO_HIGH;
} else {
last = DXPop();
}
} else {
last = first + GetInt() - 1;
}
if( !DoSubstring( first, last, InitVar->u.ns.xt.size ) ) {
NameStmtErr( EV_SSTR_INVALID, InitVar, PR_DATA );
}
DtOffset += first - 1;
DtItemSize = last - first + 1;
}
static bool SubStr( string *scb ) {
//=====================================
// Get a substring list.
intstar4 ss1;
intstar4 ss2;
ss1 = 1;
ss2 = scb->len;
if( !ScanChar( ':' ) ) {
if( !ScanSNum( &ss1 ) ) return( FALSE );
if( !ScanChar( ':' ) ) return( FALSE );
}
if( !ScanChar( ')' ) ) {
if( !ScanSNum( &ss2 ) ) return( FALSE );
if( !ScanChar( ')' ) ) return( FALSE );
}
if( !DoSubstring( ss1, ss2, scb->len ) ) return( FALSE );
scb->len = ss2 - ss1 + 1;
scb->strptr = scb->strptr + ss1 - 1;
return( TRUE );
}
