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29 * @(#)rec_search.c 8.4 (Berkeley) 7/14/94
30 * $DragonFly: src/lib/libc/db/recno/rec_search.c,v 1.5 2005/11/12 23:01:55 swildner Exp $
33 #include <sys/types.h>
42 * __REC_SEARCH -- Search a btree for a key.
47 * op: search operation
50 * EPG for matching record, if any, or the EPG for the location of the
51 * key, if it were inserted into the tree.
54 * The EPG for matching record, if any, or the EPG for the location
55 * of the key, if it were inserted into the tree, is entered into
56 * the bt_cur field of the tree. A pointer to the field is returned.
59 __rec_search(BTREE *t, recno_t recno, enum SRCHOP op)
71 for (pg = P_ROOT, total = 0;;) {
72 if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
74 if (h->flags & P_RLEAF) {
76 t->bt_cur.index = recno - total;
79 for (index = 0, top = NEXTINDEX(h);;) {
80 r = GETRINTERNAL(h, index);
81 if (++index == top || total + r->nrecs > recno)
86 BT_PUSH(t, pg, index - 1);
91 --GETRINTERNAL(h, (index - 1))->nrecs;
92 mpool_put(t->bt_mp, h, MPOOL_DIRTY);
95 ++GETRINTERNAL(h, (index - 1))->nrecs;
96 mpool_put(t->bt_mp, h, MPOOL_DIRTY);
99 mpool_put(t->bt_mp, h, 0);
104 /* Try and recover the tree. */
105 err: sverrno = errno;
107 while ((parent = BT_POP(t)) != NULL) {
108 if ((h = mpool_get(t->bt_mp, parent->pgno, 0)) == NULL)
111 --GETRINTERNAL(h, parent->index)->nrecs;
113 ++GETRINTERNAL(h, parent->index)->nrecs;
114 mpool_put(t->bt_mp, h, MPOOL_DIRTY);