/*
* __REC_GET -- Get a record from the btree.
*
* Parameters:
* dbp: pointer to access method
* key: key to find
* data: data to return
* flag: currently unused
*
* Returns:
* RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
*/
int
__rec_get(const DB *dbp, const DBT *key, DBT *data, unsigned int flags)
{
BTREE *t;
EPG *e;
recno_t nrec;
int status;
t = dbp->internal;
/* Toss any page pinned across calls. */
if (t->bt_pinned != NULL) {
mpool_put(t->bt_mp, t->bt_pinned, 0);
t->bt_pinned = NULL;
}
/* Get currently doesn't take any flags, and keys of 0 are illegal. */
if (flags || (nrec = *(recno_t *)key->data) == 0) {
errno = EINVAL;
return (RET_ERROR);
}
/*
* If we haven't seen this record yet, try to find it in the
* original file.
*/
if (nrec > t->bt_nrecs) {
if (F_ISSET(t, R_EOF | R_INMEM))
return (RET_SPECIAL);
if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS)
return (status);
}
--nrec;
if ((e = __rec_search(t, nrec, SEARCH)) == NULL)
return (RET_ERROR);
status = __rec_ret(t, e, 0, NULL, data);
if (F_ISSET(t, B_DB_LOCK))
mpool_put(t->bt_mp, e->page, 0);
else
t->bt_pinned = e->page;
return (status);
}
/*
* __REC_SEQ -- Recno sequential scan interface.
*
* Parameters:
* dbp: pointer to access method
* key: key for positioning and return value
* data: data return value
* flags: R_CURSOR, R_FIRST, R_LAST, R_NEXT, R_PREV.
*
* Returns:
* RET_ERROR, RET_SUCCESS or RET_SPECIAL if there's no next key.
*/
int
__rec_seq(const DB *dbp, DBT *key, DBT *data, u_int flags)
{
BTREE *t;
EPG *e;
recno_t nrec;
int status;
t = dbp->internal;
/* Toss any page pinned across calls. */
if (t->bt_pinned != NULL) {
mpool_put(t->bt_mp, t->bt_pinned, 0);
t->bt_pinned = NULL;
}
switch(flags) {
case R_CURSOR:
if ((nrec = *(recno_t *)key->data) == 0)
goto einval;
break;
case R_NEXT:
if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
nrec = t->bt_cursor.rcursor + 1;
break;
}
/* FALLTHROUGH */
case R_FIRST:
nrec = 1;
break;
case R_PREV:
if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
if ((nrec = t->bt_cursor.rcursor - 1) == 0)
return (RET_SPECIAL);
break;
}
/* FALLTHROUGH */
case R_LAST:
if (!F_ISSET(t, R_EOF | R_INMEM) &&
t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
return (RET_ERROR);
nrec = t->bt_nrecs;
break;
default:
einval: errno = EINVAL;
return (RET_ERROR);
}
if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) {
if (!F_ISSET(t, R_EOF | R_INMEM) &&
(status = t->bt_irec(t, nrec)) != RET_SUCCESS)
return (status);
if (t->bt_nrecs == 0 || nrec > t->bt_nrecs)
return (RET_SPECIAL);
}
if ((e = __rec_search(t, nrec - 1, SEARCH)) == NULL)
return (RET_ERROR);
F_SET(&t->bt_cursor, CURS_INIT);
t->bt_cursor.rcursor = nrec;
status = __rec_ret(t, e, nrec, key, data);
if (F_ISSET(t, B_DB_LOCK))
mpool_put(t->bt_mp, e->page, 0);
else
t->bt_pinned = e->page;
return (status);
}
/*
* __REC_PUT -- Add a recno item to the tree.
*
* Parameters:
* dbp: pointer to access method
* key: key
* data: data
* flag: R_CURSOR, R_IAFTER, R_IBEFORE, R_NOOVERWRITE
*
* Returns:
* RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key is
* already in the tree and R_NOOVERWRITE specified.
*/
int
__rec_put(const DB *dbp, DBT *key, const DBT *data, u_int flags)
{
BTREE *t;
DBT fdata, tdata;
recno_t nrec;
int status;
t = dbp->internal;
/* Toss any page pinned across calls. */
if (t->bt_pinned != NULL) {
mpool_put(t->bt_mp, t->bt_pinned, 0);
t->bt_pinned = NULL;
}
/*
* If using fixed-length records, and the record is long, return
* EINVAL. If it's short, pad it out. Use the record data return
* memory, it's only short-term.
*/
if (F_ISSET(t, R_FIXLEN) && data->size != t->bt_reclen) {
if (data->size > t->bt_reclen)
goto einval;
if (t->bt_rdata.size < t->bt_reclen) {
t->bt_rdata.data = t->bt_rdata.data == NULL ?
malloc(t->bt_reclen) :
realloc(t->bt_rdata.data, t->bt_reclen);
if (t->bt_rdata.data == NULL)
return (RET_ERROR);
t->bt_rdata.size = t->bt_reclen;
}
memmove(t->bt_rdata.data, data->data, data->size);
memset((char *)t->bt_rdata.data + data->size,
t->bt_bval, t->bt_reclen - data->size);
fdata.data = t->bt_rdata.data;
fdata.size = t->bt_reclen;
} else {
fdata.data = data->data;
fdata.size = data->size;
}
switch (flags) {
case R_CURSOR:
if (!F_ISSET(&t->bt_cursor, CURS_INIT))
goto einval;
nrec = t->bt_cursor.rcursor;
break;
case R_SETCURSOR:
if ((nrec = *(recno_t *)key->data) == 0)
goto einval;
break;
case R_IAFTER:
if ((nrec = *(recno_t *)key->data) == 0) {
nrec = 1;
flags = R_IBEFORE;
}
break;
case 0:
case R_IBEFORE:
if ((nrec = *(recno_t *)key->data) == 0)
goto einval;
break;
case R_NOOVERWRITE:
if ((nrec = *(recno_t *)key->data) == 0)
goto einval;
if (nrec <= t->bt_nrecs)
return (RET_SPECIAL);
break;
default:
einval:
errno = EINVAL;
return (RET_ERROR);
}
/*
* Make sure that records up to and including the put record are
* already in the database. If skipping records, create empty ones.
*/
if (nrec > t->bt_nrecs) {
if (!F_ISSET(t, R_EOF | R_INMEM) &&
t->bt_irec(t, nrec) == RET_ERROR)
return (RET_ERROR);
if (nrec > t->bt_nrecs + 1) {
if (F_ISSET(t, R_FIXLEN)) {
if ((tdata.data =
(void *)malloc(t->bt_reclen)) == NULL)
return (RET_ERROR);
tdata.size = t->bt_reclen;
memset(tdata.data, t->bt_bval, tdata.size);
} else {
tdata.data = NULL;
tdata.size = 0;
}
while (nrec > t->bt_nrecs + 1)
if (__rec_iput(t,
t->bt_nrecs, &tdata, 0) != RET_SUCCESS)
return (RET_ERROR);
if (F_ISSET(t, R_FIXLEN))
free(tdata.data);
}
}
if ((status = __rec_iput(t, nrec - 1, &fdata, flags)) != RET_SUCCESS)
return (status);
if (flags == R_SETCURSOR)
t->bt_cursor.rcursor = nrec;
F_SET(t, R_MODIFIED);
return (__rec_ret(t, NULL, nrec, key, NULL));
}
