/*
* db_eget --
* Front-end to db_get, special case handling for empty files.
*
* PUBLIC: int db_eget __P((SCR *, db_recno_t, CHAR_T **, size_t *, int *));
*/
int
db_eget(SCR *sp, db_recno_t lno, CHAR_T **pp, size_t *lenp, int *isemptyp)
/* Line number. */
/* Pointer store. */
/* Length store. */
{
db_recno_t l1;
if (isemptyp != NULL)
*isemptyp = 0;
/* If the line exists, simply return it. */
if (!db_get(sp, lno, 0, pp, lenp))
return (0);
/*
* If the user asked for line 0 or line 1, i.e. the only possible
* line in an empty file, find the last line of the file; db_last
* fails loudly.
*/
if ((lno == 0 || lno == 1) && db_last(sp, &l1))
return (1);
/* If the file isn't empty, fail loudly. */
if ((lno != 0 && lno != 1) || l1 != 0) {
db_err(sp, lno);
return (1);
}
if (isemptyp != NULL)
*isemptyp = 1;
return (1);
}
/*
* db_get --
* Look in the text buffers for a line, followed by the cache, followed
* by the database.
*
* PUBLIC: int db_get __P((SCR *, db_recno_t, u_int32_t, CHAR_T **, size_t *));
*/
int
db_get(SCR *sp, db_recno_t lno, u_int32_t flags, CHAR_T **pp, size_t *lenp)
/* Line number. */ /* Pointer store. */ /* Length store. */
{
DBT data, key;
EXF *ep;
TEXT *tp;
db_recno_t l1, l2;
const CHAR_T *wp;
size_t wlen;
size_t nlen;
/*
* The underlying recno stuff handles zero by returning NULL, but
* have to have an OOB condition for the look-aside into the input
* buffer anyway.
*/
if (lno == 0)
goto err1;
/* Check for no underlying file. */
if ((ep = sp->ep) == NULL) {
ex_emsg(sp, NULL, EXM_NOFILEYET);
goto err3;
}
if (LF_ISSET(DBG_NOCACHE))
goto nocache;
/*
* Look-aside into the TEXT buffers and see if the line we want
* is there.
*/
if (F_ISSET(sp, SC_TINPUT)) {
l1 = ((TEXT *)sp->tiq.cqh_first)->lno;
l2 = ((TEXT *)sp->tiq.cqh_last)->lno;
if (l1 <= lno && l2 >= lno) {
#if defined(DEBUG) && 0
vtrace(sp,
"retrieve TEXT buffer line %lu\n", (u_long)lno);
#endif
for (tp = sp->tiq.cqh_first;
tp->lno != lno; tp = tp->q.cqe_next);
if (lenp != NULL)
*lenp = tp->len;
if (pp != NULL)
*pp = tp->lb;
return (0);
}
/*
* Adjust the line number for the number of lines used
* by the text input buffers.
*/
if (lno > l2)
lno -= l2 - l1;
}
/* Look-aside into the cache, and see if the line we want is there. */
if (lno == sp->c_lno) {
#if defined(DEBUG) && 0
vtrace(sp, "retrieve cached line %lu\n", (u_long)lno);
#endif
if (lenp != NULL)
*lenp = sp->c_len;
if (pp != NULL)
*pp = sp->c_lp;
return (0);
}
sp->c_lno = OOBLNO;
nocache:
nlen = 1024;
retry:
/* data.size contains length in bytes */
BINC_GOTO(sp, CHAR_T, sp->c_lp, sp->c_blen, nlen);
/* Get the line from the underlying database. */
memset(&key, 0, sizeof(key));
key.data = &lno;
key.size = sizeof(lno);
memset(&data, 0, sizeof(data));
data.data = sp->c_lp;
data.ulen = sp->c_blen;
data.flags = DB_DBT_USERMEM;
switch (ep->db->get(ep->db, NULL, &key, &data, 0)) {
case DB_BUFFER_SMALL:
nlen = data.size;
goto retry;
default:
goto err2;
case DB_NOTFOUND:
err1: if (LF_ISSET(DBG_FATAL))
err2: db_err(sp, lno);
alloc_err:
err3: if (lenp != NULL)
*lenp = 0;
if (pp != NULL)
*pp = NULL;
return (1);
case 0:
;
}
if (FILE2INT(sp, data.data, data.size, wp, wlen)) {
if (!F_ISSET(sp, SC_CONV_ERROR)) {
F_SET(sp, SC_CONV_ERROR);
msgq(sp, M_ERR, "324|Conversion error on line %d", lno);
}
goto err3;
}
/* Reset the cache. */
if (wp != data.data) {
BINC_GOTOW(sp, sp->c_lp, sp->c_blen, wlen);
MEMCPYW(sp->c_lp, wp, wlen);
}
sp->c_lno = lno;
sp->c_len = wlen;
#if defined(DEBUG) && 0
vtrace(sp, "retrieve DB line %lu\n", (u_long)lno);
#endif
if (lenp != NULL)
*lenp = wlen;
if (pp != NULL)
*pp = sp->c_lp;
return (0);
}
/*
* db_get --
* Look in the text buffers for a line, followed by the cache, followed
* by the database.
*
* PUBLIC: int db_get(SCR *, recno_t, u_int32_t, CHAR_T **, size_t *);
*/
int
db_get(
SCR *sp,
recno_t lno, /* Line number. */
u_int32_t flags,
CHAR_T **pp, /* Pointer store. */
size_t *lenp) /* Length store. */
{
DBT data, key;
EXF *ep;
TEXT *tp;
recno_t l1, l2;
CHAR_T *wp;
size_t wlen;
/*
* The underlying recno stuff handles zero by returning NULL, but
* have to have an OOB condition for the look-aside into the input
* buffer anyway.
*/
if (lno == 0)
goto err1;
/* Check for no underlying file. */
if ((ep = sp->ep) == NULL) {
ex_emsg(sp, NULL, EXM_NOFILEYET);
goto err3;
}
if (LF_ISSET(DBG_NOCACHE))
goto nocache;
/*
* Look-aside into the TEXT buffers and see if the line we want
* is there.
*/
if (F_ISSET(sp, SC_TINPUT)) {
l1 = ((TEXT *)TAILQ_FIRST(sp->tiq))->lno;
l2 = ((TEXT *)TAILQ_LAST(sp->tiq, _texth))->lno;
if (l1 <= lno && l2 >= lno) {
#if defined(DEBUG) && 0
TRACE(sp, "retrieve TEXT buffer line %lu\n", (u_long)lno);
#endif
for (tp = TAILQ_FIRST(sp->tiq);
tp->lno != lno; tp = TAILQ_NEXT(tp, q));
if (lenp != NULL)
*lenp = tp->len;
if (pp != NULL)
*pp = tp->lb;
return (0);
}
/*
* Adjust the line number for the number of lines used
* by the text input buffers.
*/
if (lno > l2)
lno -= l2 - l1;
}
/* Look-aside into the cache, and see if the line we want is there. */
if (lno == ep->c_lno) {
#if defined(DEBUG) && 0
TRACE(sp, "retrieve cached line %lu\n", (u_long)lno);
#endif
if (lenp != NULL)
*lenp = ep->c_len;
if (pp != NULL)
*pp = ep->c_lp;
return (0);
}
ep->c_lno = OOBLNO;
nocache:
/* Get the line from the underlying database. */
key.data = &lno;
key.size = sizeof(lno);
switch (ep->db->get(ep->db, &key, &data, 0)) {
case -1:
goto err2;
case 1:
err1: if (LF_ISSET(DBG_FATAL))
err2: db_err(sp, lno);
alloc_err:
err3: if (lenp != NULL)
*lenp = 0;
if (pp != NULL)
*pp = NULL;
return (1);
}
if (FILE2INT(sp, data.data, data.size, wp, wlen)) {
if (!F_ISSET(sp, SC_CONV_ERROR)) {
F_SET(sp, SC_CONV_ERROR);
msgq(sp, M_ERR, "324|Conversion error on line %d", lno);
}
goto err3;
}
/* Reset the cache. */
if (wp != data.data) {
BINC_GOTOW(sp, ep->c_lp, ep->c_blen, wlen);
MEMCPY(ep->c_lp, wp, wlen);
} else
ep->c_lp = data.data;
ep->c_lno = lno;
ep->c_len = wlen;
#if defined(DEBUG) && 0
TRACE(sp, "retrieve DB line %lu\n", (u_long)lno);
#endif
if (lenp != NULL)
*lenp = wlen;
if (pp != NULL)
*pp = ep->c_lp;
return (0);
}
