int mkrep(int mach, int lb, int ub)
{
int base_mach, tail, copy, i;
base_mach = copysingl( mach, lb - 1 );
if ( ub == INFINITY )
{
copy = dupmachine( mach );
mach = link_machines( mach,
link_machines( base_mach, mkclos( copy ) ) );
}
else
{
tail = mkstate( SYM_EPSILON );
for ( i = lb; i < ub; ++i )
{
copy = dupmachine( mach );
tail = mkopt( link_machines( copy, tail ) );
}
mach = link_machines( mach, link_machines( base_mach, tail ) );
}
return ( mach );
}
int mkor(int first, int second)
{
int eps, orend;
if ( first == NIL )
return ( second );
else if ( second == NIL )
return ( first );
else
{
/* see comment in mkopt() about why we can't use the first state
* of "first" or "second" if they satisfy "FREE_EPSILON"
*/
eps = mkstate( SYM_EPSILON );
first = link_machines( eps, first );
mkxtion( first, second );
if ( SUPER_FREE_EPSILON(finalst[first]) &&
accptnum[finalst[first]] == NIL )
{
orend = finalst[first];
mkxtion( finalst[second], orend );
}
else if ( SUPER_FREE_EPSILON(finalst[second]) &&
accptnum[finalst[second]] == NIL )
{
orend = finalst[second];
mkxtion( finalst[first], orend );
}
else
{
eps = mkstate( SYM_EPSILON );
first = link_machines( first, eps );
orend = finalst[first];
mkxtion( finalst[second], orend );
}
}
finalst[first] = orend;
return ( first );
}
int copysingl(int singl, int num)
{
int copy, i;
copy = mkstate( SYM_EPSILON );
for ( i = 1; i <= num; ++i )
copy = link_machines( copy, dupmachine( singl ) );
return ( copy );
}
int mkopt(int mach)
{
int eps;
if ( ! SUPER_FREE_EPSILON(finalst[mach]) )
{
eps = mkstate( SYM_EPSILON );
mach = link_machines( mach, eps );
}
/* can't skimp on the following if FREE_EPSILON(mach) is true because
* some state interior to "mach" might point back to the beginning
* for a closure
*/
eps = mkstate( SYM_EPSILON );
mach = link_machines( eps, mach );
mkxtion( mach, finalst[mach] );
return ( mach );
}
/* mkposcl - convert a machine into a positive closure
*
* synopsis
* new = mkposcl( state );
*
* new - a machine matching the positive closure of "state"
*/
int
mkposcl(int state)
{
int eps;
if (SUPER_FREE_EPSILON(finalst[state])) {
mkxtion(finalst[state], state);
return state;
}
else {
eps = mkstate(SYM_EPSILON);
mkxtion(eps, state);
return link_machines(state, eps);
}
}
void add_accept(int mach, int accepting_number)
{
/* hang the accepting number off an epsilon state. if it is associated
* with a state that has a non-epsilon out-transition, then the state
* will accept BEFORE it makes that transition, i.e., one character
* too soon
*/
if ( transchar[finalst[mach]] == SYM_EPSILON )
accptnum[finalst[mach]] = accepting_number;
else
{
int astate = mkstate( SYM_EPSILON );
accptnum[astate] = accepting_number;
mach = link_machines( mach, astate );
}
}
