Asterisk - The Open Source Telephony Project  GIT-master-09303e8
rec_seq.c
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1 /*-
2  * Copyright (c) 1991, 1993, 1994
3  * The Regents of the University of California. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  * notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  * notice, this list of conditions and the following disclaimer in the
12  * documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  * must display the following acknowledgement:
15  * This product includes software developed by the University of
16  * California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  * may be used to endorse or promote products derived from this software
19  * without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)rec_seq.c 8.3 (Berkeley) 7/14/94";
36 #endif /* not lint */
37 
38 #include <sys/types.h>
39 
40 #include <errno.h>
41 #include <limits.h>
42 #include <stdio.h>
43 #include <string.h>
44 
45 #include "../include/db.h"
46 #include "recno.h"
47 
48 /*
49  * __REC_SEQ -- Recno sequential scan interface.
50  *
51  * Parameters:
52  * dbp: pointer to access method
53  * key: key for positioning and return value
54  * data: data return value
55  * flags: R_CURSOR, R_FIRST, R_LAST, R_NEXT, R_PREV.
56  *
57  * Returns:
58  * RET_ERROR, RET_SUCCESS or RET_SPECIAL if there's no next key.
59  */
60 int
61 __rec_seq(dbp, key, data, flags)
62  const DB *dbp;
63  DBT *key, *data;
64  u_int flags;
65 {
66  BTREE *t;
67  EPG *e;
68  recno_t nrec;
69  int status;
70 
71  t = dbp->internal;
72 
73  /* Toss any page pinned across calls. */
74  if (t->bt_pinned != NULL) {
75  mpool_put(t->bt_mp, t->bt_pinned, 0);
76  t->bt_pinned = NULL;
77  }
78 
79  switch(flags) {
80  case R_CURSOR:
81  if ((nrec = *(recno_t *)key->data) == 0)
82  goto einval;
83  break;
84  case R_NEXT:
85  if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
86  nrec = t->bt_cursor.rcursor + 1;
87  break;
88  }
89  /* FALLTHROUGH */
90  case R_FIRST:
91  nrec = 1;
92  break;
93  case R_PREV:
94  if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
95  if ((nrec = t->bt_cursor.rcursor - 1) == 0)
96  return (RET_SPECIAL);
97  break;
98  }
99  /* FALLTHROUGH */
100  case R_LAST:
101  if (!F_ISSET(t, R_EOF | R_INMEM) &&
102  t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
103  return (RET_ERROR);
104  nrec = t->bt_nrecs;
105  break;
106  default:
107 einval: errno = EINVAL;
108  return (RET_ERROR);
109  }
110 
111  if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) {
112  if (!F_ISSET(t, R_EOF | R_INMEM) &&
113  (status = t->bt_irec(t, nrec)) != RET_SUCCESS)
114  return (status);
115  if (t->bt_nrecs == 0 || nrec > t->bt_nrecs)
116  return (RET_SPECIAL);
117  }
118 
119  if ((e = __rec_search(t, nrec - 1, SEARCH)) == NULL)
120  return (RET_ERROR);
121 
122  F_SET(&t->bt_cursor, CURS_INIT);
123  t->bt_cursor.rcursor = nrec;
124 
125  status = __rec_ret(t, e, nrec, key, data);
126  if (F_ISSET(t, B_DB_LOCK))
127  mpool_put(t->bt_mp, e->page, 0);
128  else
129  t->bt_pinned = e->page;
130  return (status);
131 }
#define R_CURSOR
Definition: db.h:91
void * data
Definition: db.h:86
#define RET_ERROR
Definition: db.h:51
#define F_SET(p, f)
Definition: btree.h:40
#define F_ISSET(p, f)
Definition: btree.h:42
int mpool_put(MPOOL *mp, void *page, u_int flags)
Definition: mpool.c:251
CURSOR bt_cursor
Definition: btree.h:320
recno_t rcursor
Definition: btree.h:286
Definition: btree.h:254
void * internal
Definition: db.h:137
Definition: db.h:85
#define NULL
Definition: resample.c:96
EPG * __rec_search(BTREE *t, recno_t recno, enum SRCHOP op)
Definition: rec_search.c:64
recno_t bt_nrecs
Definition: btree.h:360
Definition: btree.h:312
int __rec_ret(BTREE *t, EPG *e, recno_t nrec, DBT *key, DBT *data)
Definition: rec_utils.c:62
#define R_LAST
Definition: db.h:96
#define RET_SUCCESS
Definition: db.h:52
PAGE * bt_pinned
Definition: btree.h:318
int __rec_seq(DB *dbp, DBT *key, DBT *data, u_int flags) const
Definition: rec_seq.c:61
#define R_PREV
Definition: db.h:99
PAGE * page
Definition: btree.h:255
#define CURS_INIT
Definition: btree.h:291
MPOOL * bt_mp
Definition: btree.h:313
static DB * dbp
Definition: hsearch.c:49
int errno
#define R_NEXT
Definition: db.h:97
#define R_INMEM
Definition: btree.h:381
Definition: recno.h:36
#define R_EOF
Definition: btree.h:378
#define R_FIRST
Definition: db.h:93
#define MAX_REC_NUMBER
Definition: db.h:81
Definition: db.h:129
#define RET_SPECIAL
Definition: db.h:53
u_int32_t recno_t
Definition: db.h:82
#define B_DB_LOCK
Definition: btree.h:385
jack_status_t status
Definition: app_jack.c:146