Asterisk - The Open Source Telephony Project  GIT-master-4a4f1a5
rec_open.c
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1 /*-
2  * Copyright (c) 1990, 1993, 1994
3  * The Regents of the University of California. All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Olson.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  * notice, this list of conditions and the following disclaimer in the
15  * documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  * must display the following acknowledgement:
18  * This product includes software developed by the University of
19  * California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  * may be used to endorse or promote products derived from this software
22  * without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] = "@(#)rec_open.c 8.10 (Berkeley) 9/1/94";
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include <sys/types.h>
42 #include <sys/mman.h>
43 #include <sys/stat.h>
44 
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <limits.h>
48 #include <stddef.h>
49 #include <stdio.h>
50 #include <unistd.h>
51 
52 #include "../include/db.h"
53 #include "recno.h"
54 
55 DB *
56 __rec_open(fname, flags, mode, openinfo, dflags)
57  const char *fname;
58  int flags, mode, dflags;
59  const RECNOINFO *openinfo;
60 {
61  BTREE *t;
62  BTREEINFO btopeninfo;
63  DB *dbp;
64  PAGE *h;
65  struct stat sb;
66  int rfd = 0, sverrno;
67 
68  /* Open the user's file -- if this fails, we're done. */
69  if (fname != NULL && (rfd = open(fname, flags, mode)) < 0)
70  return (NULL);
71 
72  /* Create a btree in memory (backed by disk). */
73  dbp = NULL;
74  if (openinfo) {
75  if (openinfo->flags & ~(R_FIXEDLEN | R_NOKEY | R_SNAPSHOT))
76  goto einval;
77  btopeninfo.flags = 0;
78  btopeninfo.cachesize = openinfo->cachesize;
79  btopeninfo.maxkeypage = 0;
80  btopeninfo.minkeypage = 0;
81  btopeninfo.psize = openinfo->psize;
82  btopeninfo.compare = NULL;
83  btopeninfo.prefix = NULL;
84  btopeninfo.lorder = openinfo->lorder;
85  dbp = __bt_open(openinfo->bfname,
86  O_RDWR, S_IRUSR | S_IWUSR, &btopeninfo, dflags);
87  } else
88  dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL, dflags);
89  if (dbp == NULL)
90  goto err;
91 
92  /*
93  * Some fields in the tree structure are recno specific. Fill them
94  * in and make the btree structure look like a recno structure. We
95  * don't change the bt_ovflsize value, it's close enough and slightly
96  * bigger.
97  */
98  t = dbp->internal;
99  if (openinfo) {
100  if (openinfo->flags & R_FIXEDLEN) {
101  F_SET(t, R_FIXLEN);
102  t->bt_reclen = openinfo->reclen;
103  if (t->bt_reclen == 0)
104  goto einval;
105  }
106  t->bt_bval = openinfo->bval;
107  } else
108  t->bt_bval = '\n';
109 
110  F_SET(t, R_RECNO);
111  if (fname == NULL)
112  F_SET(t, R_EOF | R_INMEM);
113  else
114  t->bt_rfd = rfd;
115 
116  if (fname != NULL) {
117  /*
118  * In 4.4BSD, stat(2) returns true for ISSOCK on pipes.
119  * Unfortunately, that's not portable, so we use lseek
120  * and check the errno values.
121  */
122  errno = 0;
123  if (lseek(rfd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) {
124  switch (flags & O_ACCMODE) {
125  case O_RDONLY:
126  F_SET(t, R_RDONLY);
127  break;
128  default:
129  goto einval;
130  }
131 slow: if ((t->bt_rfp = fdopen(rfd, "r")) == NULL)
132  goto err;
133  F_SET(t, R_CLOSEFP);
134  t->bt_irec =
136  } else {
137  switch (flags & O_ACCMODE) {
138  case O_RDONLY:
139  F_SET(t, R_RDONLY);
140  break;
141  case O_RDWR:
142  break;
143  default:
144  goto einval;
145  }
146 
147  if (fstat(rfd, &sb))
148  goto err;
149  /*
150  * Kluge -- we'd like to test to see if the file is too
151  * big to mmap. Since, we don't know what size or type
152  * off_t's or size_t's are, what the largest unsigned
153  * integral type is, or what random insanity the local
154  * C compiler will perpetrate, doing the comparison in
155  * a portable way is flatly impossible. Hope that mmap
156  * fails if the file is too large.
157  */
158  if (sb.st_size == 0)
159  F_SET(t, R_EOF);
160  else {
161 #ifdef MMAP_NOT_AVAILABLE
162  /*
163  * XXX
164  * Mmap doesn't work correctly on many current
165  * systems. In particular, it can fail subtly,
166  * with cache coherency problems. Don't use it
167  * for now.
168  */
169  t->bt_msize = sb.st_size;
170  if ((t->bt_smap = mmap(NULL, t->bt_msize,
171  PROT_READ, MAP_PRIVATE, rfd,
172  (off_t)0)) == MAP_FAILED
173  goto slow;
174  t->bt_cmap = t->bt_smap;
175  t->bt_emap = t->bt_smap + sb.st_size;
176  t->bt_irec = F_ISSET(t, R_FIXLEN) ?
178  F_SET(t, R_MEMMAPPED);
179 #else
180  goto slow;
181 #endif
182  }
183  }
184  }
185 
186  /* Use the recno routines. */
187  dbp->close = __rec_close;
188  dbp->del = __rec_delete;
189  dbp->fd = __rec_fd;
190  dbp->get = __rec_get;
191  dbp->put = __rec_put;
192  dbp->seq = __rec_seq;
193  dbp->sync = __rec_sync;
194 
195  /* If the root page was created, reset the flags. */
196  if ((h = mpool_get(t->bt_mp, P_ROOT, 0)) == NULL)
197  goto err;
198  if ((h->flags & P_TYPE) == P_BLEAF) {
199  F_CLR(h, P_TYPE);
200  F_SET(h, P_RLEAF);
201  mpool_put(t->bt_mp, h, MPOOL_DIRTY);
202  } else
203  mpool_put(t->bt_mp, h, 0);
204 
205  if (openinfo && openinfo->flags & R_SNAPSHOT &&
206  !F_ISSET(t, R_EOF | R_INMEM) &&
207  t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
208  goto err;
209  return (dbp);
210 
211 einval: errno = EINVAL;
212 err: sverrno = errno;
213  if (dbp != NULL)
214  (void)__bt_close(dbp);
215  if (fname != NULL)
216  (void)close(rfd);
217  errno = sverrno;
218  return (NULL);
219 }
220 
221 int
223  const DB *dbp;
224 {
225  BTREE *t;
226 
227  t = dbp->internal;
228 
229  /* Toss any page pinned across calls. */
230  if (t->bt_pinned != NULL) {
231  mpool_put(t->bt_mp, t->bt_pinned, 0);
232  t->bt_pinned = NULL;
233  }
234 
235  /* In-memory database can't have a file descriptor. */
236  if (F_ISSET(t, R_INMEM)) {
237  errno = ENOENT;
238  return (-1);
239  }
240  return (t->bt_rfd);
241 }
dflags
Definition: app_dictate.c:63
int __bt_close(DB *dbp)
Definition: bt_close.c:64
DB * __bt_open(char *fname, int flags, int mode, const BTREEINFO *openinfo, int dflags) const
Definition: bt_open.c:90
#define F_ISSET(p, f)
Definition: btree.h:42
#define P_RLEAF
Definition: btree.h:84
#define R_CLOSEFP
Definition: btree.h:377
#define R_RECNO
Definition: btree.h:375
#define R_MEMMAPPED
Definition: btree.h:380
#define P_TYPE
Definition: btree.h:85
#define R_RDONLY
Definition: btree.h:383
#define F_SET(p, f)
Definition: btree.h:40
#define R_INMEM
Definition: btree.h:381
#define F_CLR(p, f)
Definition: btree.h:41
#define R_EOF
Definition: btree.h:378
#define P_BLEAF
Definition: btree.h:81
#define R_FIXLEN
Definition: btree.h:379
#define P_ROOT
Definition: btree.h:65
#define R_SNAPSHOT
Definition: db.h:177
#define MAX_REC_NUMBER
Definition: db.h:81
#define RET_ERROR
Definition: db.h:51
#define R_NOKEY
Definition: db.h:176
#define R_FIXEDLEN
Definition: db.h:175
static DB * dbp
Definition: hsearch.c:49
int errno
int mpool_put(MPOOL *mp, void *page, u_int flags)
Definition: mpool.c:251
void * mpool_get(MPOOL *mp, pgno_t pgno, u_int flags)
Definition: mpool.c:165
#define MPOOL_DIRTY
Definition: mpool.h:61
int __rec_close(DB *dbp)
Definition: rec_close.c:60
int __rec_sync(DB *dbp, u_int flags) const
Definition: rec_close.c:107
int __rec_delete(DB *dbp, const DBT *key, u_int flags) const
Definition: rec_delete.c:64
int __rec_vmap(BTREE *t, recno_t top)
Definition: rec_get.c:285
int __rec_fpipe(BTREE *t, recno_t top)
Definition: rec_get.c:122
int __rec_get(DB *dbp, const DBT *key, DBT *data, u_int flags) const
Definition: rec_get.c:63
int __rec_vpipe(BTREE *t, recno_t top)
Definition: rec_get.c:178
int __rec_fmap(BTREE *t, recno_t top)
Definition: rec_get.c:235
int __rec_fd(DB *dbp) const
Definition: rec_open.c:222
DB * __rec_open(char *fname, int flags, int mode, const RECNOINFO *openinfo, int dflags) const
Definition: rec_open.c:56
int __rec_put(DB *dbp, DBT *key, const DBT *data, u_int flags) const
Definition: rec_put.c:62
int __rec_seq(DB *dbp, DBT *key, DBT *data, u_int flags) const
Definition: rec_seq.c:61
#define NULL
Definition: resample.c:96
Definition: db.h:145
u_int cachesize
Definition: db.h:148
int minkeypage
Definition: db.h:150
u_int psize
Definition: db.h:151
int lorder
Definition: db.h:156
int maxkeypage
Definition: db.h:149
u_long flags
Definition: db.h:147
Definition: db.h:174
u_int cachesize
Definition: db.h:179
char * bfname
Definition: db.h:184
size_t reclen
Definition: db.h:182
u_int psize
Definition: db.h:180
u_char bval
Definition: db.h:183
int lorder
Definition: db.h:181
u_long flags
Definition: db.h:178
Definition: db.h:129
void * internal
Definition: db.h:137
Definition: btree.h:312
caddr_t bt_cmap
Definition: btree.h:355
MPOOL * bt_mp
Definition: btree.h:313
caddr_t bt_emap
Definition: btree.h:357
PAGE * bt_pinned
Definition: btree.h:318
u_char bt_bval
Definition: btree.h:362
size_t bt_msize
Definition: btree.h:358
size_t bt_reclen
Definition: btree.h:361
FILE * bt_rfp
Definition: btree.h:352
caddr_t bt_smap
Definition: btree.h:356
int bt_rfd
Definition: btree.h:353
Definition: btree.h:75
u_int32_t flags
Definition: btree.h:87