diff options
Diffstat (limited to 'usr/src/lib/libast/common/cdt/dtview.c')
| -rw-r--r-- | usr/src/lib/libast/common/cdt/dtview.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/usr/src/lib/libast/common/cdt/dtview.c b/usr/src/lib/libast/common/cdt/dtview.c new file mode 100644 index 0000000000..483f5f496f --- /dev/null +++ b/usr/src/lib/libast/common/cdt/dtview.c @@ -0,0 +1,155 @@ +/*********************************************************************** +* * +* This software is part of the ast package * +* Copyright (c) 1985-2007 AT&T Knowledge Ventures * +* and is licensed under the * +* Common Public License, Version 1.0 * +* by AT&T Knowledge Ventures * +* * +* A copy of the License is available at * +* http://www.opensource.org/licenses/cpl1.0.txt * +* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * +* * +* Information and Software Systems Research * +* AT&T Research * +* Florham Park NJ * +* * +* Glenn Fowler <gsf@research.att.com> * +* David Korn <dgk@research.att.com> * +* Phong Vo <kpv@research.att.com> * +* * +***********************************************************************/ +#include "dthdr.h" + +/* Set a view path from dict to view. +** +** Written by Kiem-Phong Vo (5/25/96) +*/ + + +#if __STD_C +static Void_t* dtvsearch(Dt_t* dt, reg Void_t* obj, reg int type) +#else +static Void_t* dtvsearch(dt,obj,type) +Dt_t* dt; +reg Void_t* obj; +reg int type; +#endif +{ + Dt_t *d, *p; + Void_t *o, *n, *ok, *nk; + int cmp, lk, sz, ky; + Dtcompar_f cmpf; + + /* these operations only happen at the top level */ + if(type&(DT_INSERT|DT_DELETE|DT_CLEAR|DT_RENEW)) + return (*(dt->meth->searchf))(dt,obj,type); + + if((type&(DT_MATCH|DT_SEARCH)) || /* order sets first/last done below */ + ((type&(DT_FIRST|DT_LAST)) && !(dt->meth->type&(DT_OBAG|DT_OSET)) ) ) + { for(d = dt; d; d = d->view) + if((o = (*(d->meth->searchf))(d,obj,type)) ) + break; + dt->walk = d; + return o; + } + + if(dt->meth->type & (DT_OBAG|DT_OSET) ) + { if(!(type & (DT_FIRST|DT_LAST|DT_NEXT|DT_PREV)) ) + return NIL(Void_t*); + + n = nk = NIL(Void_t*); p = NIL(Dt_t*); + for(d = dt; d; d = d->view) + { if(!(o = (*d->meth->searchf)(d, obj, type)) ) + continue; + _DTDSC(d->disc,ky,sz,lk,cmpf); + ok = _DTKEY(o,ky,sz); + + if(n) /* get the right one among all dictionaries */ + { cmp = _DTCMP(d,ok,nk,d->disc,cmpf,sz); + if(((type & (DT_NEXT|DT_FIRST)) && cmp < 0) || + ((type & (DT_PREV|DT_LAST)) && cmp > 0) ) + goto a_dj; + } + else /* looks good for now */ + { a_dj: p = d; + n = o; + nk = ok; + } + } + + dt->walk = p; + return n; + } + + /* non-ordered methods */ + if(!(type & (DT_NEXT|DT_PREV)) ) + return NIL(Void_t*); + + if(!dt->walk || obj != _DTOBJ(dt->walk->data->here, dt->walk->disc->link) ) + { for(d = dt; d; d = d->view) + if((o = (*(d->meth->searchf))(d, obj, DT_SEARCH)) ) + break; + dt->walk = d; + if(!(obj = o) ) + return NIL(Void_t*); + } + + for(d = dt->walk, obj = (*d->meth->searchf)(d, obj, type);; ) + { while(obj) /* keep moving until finding an uncovered object */ + { for(p = dt; ; p = p->view) + { if(p == d) /* adjacent object is uncovered */ + return obj; + if((*(p->meth->searchf))(p, obj, DT_SEARCH) ) + break; + } + obj = (*d->meth->searchf)(d, obj, type); + } + + if(!(d = dt->walk = d->view) ) /* move on to next dictionary */ + return NIL(Void_t*); + else if(type&DT_NEXT) + obj = (*(d->meth->searchf))(d,NIL(Void_t*),DT_FIRST); + else obj = (*(d->meth->searchf))(d,NIL(Void_t*),DT_LAST); + } +} + +#if __STD_C +Dt_t* dtview(reg Dt_t* dt, reg Dt_t* view) +#else +Dt_t* dtview(dt,view) +reg Dt_t* dt; +reg Dt_t* view; +#endif +{ + reg Dt_t* d; + + UNFLATTEN(dt); + if(view) + { UNFLATTEN(view); + if(view->meth != dt->meth) /* must use the same method */ + return NIL(Dt_t*); + } + + /* make sure there won't be a cycle */ + for(d = view; d; d = d->view) + if(d == dt) + return NIL(Dt_t*); + + /* no more viewing lower dictionary */ + if((d = dt->view) ) + d->nview -= 1; + dt->view = dt->walk = NIL(Dt_t*); + + if(!view) + { dt->searchf = dt->meth->searchf; + return d; + } + + /* ok */ + dt->view = view; + dt->searchf = dtvsearch; + view->nview += 1; + + return view; +} |