rec_open.c revision 1.5.2.2
1 1.5.2.2 cgd /*- 2 1.5.2.2 cgd * Copyright (c) 1990, 1993 3 1.5.2.2 cgd * The Regents of the University of California. All rights reserved. 4 1.5.2.2 cgd * 5 1.5.2.2 cgd * This code is derived from software contributed to Berkeley by 6 1.5.2.2 cgd * Mike Olson. 7 1.5.2.2 cgd * 8 1.5.2.2 cgd * Redistribution and use in source and binary forms, with or without 9 1.5.2.2 cgd * modification, are permitted provided that the following conditions 10 1.5.2.2 cgd * are met: 11 1.5.2.2 cgd * 1. Redistributions of source code must retain the above copyright 12 1.5.2.2 cgd * notice, this list of conditions and the following disclaimer. 13 1.5.2.2 cgd * 2. Redistributions in binary form must reproduce the above copyright 14 1.5.2.2 cgd * notice, this list of conditions and the following disclaimer in the 15 1.5.2.2 cgd * documentation and/or other materials provided with the distribution. 16 1.5.2.2 cgd * 3. All advertising materials mentioning features or use of this software 17 1.5.2.2 cgd * must display the following acknowledgement: 18 1.5.2.2 cgd * This product includes software developed by the University of 19 1.5.2.2 cgd * California, Berkeley and its contributors. 20 1.5.2.2 cgd * 4. Neither the name of the University nor the names of its contributors 21 1.5.2.2 cgd * may be used to endorse or promote products derived from this software 22 1.5.2.2 cgd * without specific prior written permission. 23 1.5.2.2 cgd * 24 1.5.2.2 cgd * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 1.5.2.2 cgd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 1.5.2.2 cgd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 1.5.2.2 cgd * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 1.5.2.2 cgd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 1.5.2.2 cgd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 1.5.2.2 cgd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 1.5.2.2 cgd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 1.5.2.2 cgd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 1.5.2.2 cgd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 1.5.2.2 cgd * SUCH DAMAGE. 35 1.5.2.2 cgd */ 36 1.5.2.2 cgd 37 1.5.2.2 cgd #if defined(LIBC_SCCS) && !defined(lint) 38 1.5.2.2 cgd static char sccsid[] = "@(#)rec_open.c 8.6 (Berkeley) 2/22/94"; 39 1.5.2.2 cgd #endif /* LIBC_SCCS and not lint */ 40 1.5.2.2 cgd 41 1.5.2.2 cgd #include <sys/types.h> 42 1.5.2.2 cgd #include <sys/mman.h> 43 1.5.2.2 cgd #include <sys/stat.h> 44 1.5.2.2 cgd 45 1.5.2.2 cgd #include <errno.h> 46 1.5.2.2 cgd #include <fcntl.h> 47 1.5.2.2 cgd #include <limits.h> 48 1.5.2.2 cgd #include <stddef.h> 49 1.5.2.2 cgd #include <stdio.h> 50 1.5.2.2 cgd #include <unistd.h> 51 1.5.2.2 cgd 52 1.5.2.2 cgd #include <db.h> 53 1.5.2.2 cgd #include "recno.h" 54 1.5.2.2 cgd 55 1.5.2.2 cgd DB * 56 1.5.2.2 cgd __rec_open(fname, flags, mode, openinfo, dflags) 57 1.5.2.2 cgd const char *fname; 58 1.5.2.2 cgd int flags, mode, dflags; 59 1.5.2.2 cgd const RECNOINFO *openinfo; 60 1.5.2.2 cgd { 61 1.5.2.2 cgd BTREE *t; 62 1.5.2.2 cgd BTREEINFO btopeninfo; 63 1.5.2.2 cgd DB *dbp; 64 1.5.2.2 cgd PAGE *h; 65 1.5.2.2 cgd struct stat sb; 66 1.5.2.2 cgd int rfd, sverrno; 67 1.5.2.2 cgd 68 1.5.2.2 cgd /* Open the user's file -- if this fails, we're done. */ 69 1.5.2.2 cgd if (fname != NULL && (rfd = open(fname, flags, mode)) < 0) 70 1.5.2.2 cgd return (NULL); 71 1.5.2.2 cgd 72 1.5.2.2 cgd /* Create a btree in memory (backed by disk). */ 73 1.5.2.2 cgd dbp = NULL; 74 1.5.2.2 cgd if (openinfo) { 75 1.5.2.2 cgd if (openinfo->flags & ~(R_FIXEDLEN | R_NOKEY | R_SNAPSHOT)) 76 1.5.2.2 cgd goto einval; 77 1.5.2.2 cgd btopeninfo.flags = 0; 78 1.5.2.2 cgd btopeninfo.cachesize = openinfo->cachesize; 79 1.5.2.2 cgd btopeninfo.maxkeypage = 0; 80 1.5.2.2 cgd btopeninfo.minkeypage = 0; 81 1.5.2.2 cgd btopeninfo.psize = openinfo->psize; 82 1.5.2.2 cgd btopeninfo.compare = NULL; 83 1.5.2.2 cgd btopeninfo.prefix = NULL; 84 1.5.2.2 cgd btopeninfo.lorder = openinfo->lorder; 85 1.5.2.2 cgd dbp = __bt_open(openinfo->bfname, 86 1.5.2.2 cgd O_RDWR, S_IRUSR | S_IWUSR, &btopeninfo, dflags); 87 1.5.2.2 cgd } else 88 1.5.2.2 cgd dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL, dflags); 89 1.5.2.2 cgd if (dbp == NULL) 90 1.5.2.2 cgd goto err; 91 1.5.2.2 cgd 92 1.5.2.2 cgd /* 93 1.5.2.2 cgd * Some fields in the tree structure are recno specific. Fill them 94 1.5.2.2 cgd * in and make the btree structure look like a recno structure. We 95 1.5.2.2 cgd * don't change the bt_ovflsize value, it's close enough and slightly 96 1.5.2.2 cgd * bigger. 97 1.5.2.2 cgd */ 98 1.5.2.2 cgd t = dbp->internal; 99 1.5.2.2 cgd if (openinfo) { 100 1.5.2.2 cgd if (openinfo->flags & R_FIXEDLEN) { 101 1.5.2.2 cgd SET(t, R_FIXLEN); 102 1.5.2.2 cgd t->bt_reclen = openinfo->reclen; 103 1.5.2.2 cgd if (t->bt_reclen == 0) 104 1.5.2.2 cgd goto einval; 105 1.5.2.2 cgd } 106 1.5.2.2 cgd t->bt_bval = openinfo->bval; 107 1.5.2.2 cgd } else 108 1.5.2.2 cgd t->bt_bval = '\n'; 109 1.5.2.2 cgd 110 1.5.2.2 cgd SET(t, R_RECNO); 111 1.5.2.2 cgd if (fname == NULL) 112 1.5.2.2 cgd SET(t, R_EOF | R_INMEM); 113 1.5.2.2 cgd else 114 1.5.2.2 cgd t->bt_rfd = rfd; 115 1.5.2.2 cgd t->bt_rcursor = 0; 116 1.5.2.2 cgd 117 1.5.2.2 cgd if (fname != NULL) { 118 1.5.2.2 cgd /* 119 1.5.2.2 cgd * In 4.4BSD, stat(2) returns true for ISSOCK on pipes. 120 1.5.2.2 cgd * Unfortunately, that's not portable, so we use lseek 121 1.5.2.2 cgd * and check the errno values. 122 1.5.2.2 cgd */ 123 1.5.2.2 cgd errno = 0; 124 1.5.2.2 cgd if (lseek(rfd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) { 125 1.5.2.2 cgd switch (flags & O_ACCMODE) { 126 1.5.2.2 cgd case O_RDONLY: 127 1.5.2.2 cgd SET(t, R_RDONLY); 128 1.5.2.2 cgd break; 129 1.5.2.2 cgd default: 130 1.5.2.2 cgd goto einval; 131 1.5.2.2 cgd } 132 1.5.2.2 cgd slow: if ((t->bt_rfp = fdopen(rfd, "r")) == NULL) 133 1.5.2.2 cgd goto err; 134 1.5.2.2 cgd SET(t, R_CLOSEFP); 135 1.5.2.2 cgd t->bt_irec = 136 1.5.2.2 cgd ISSET(t, R_FIXLEN) ? __rec_fpipe : __rec_vpipe; 137 1.5.2.2 cgd } else { 138 1.5.2.2 cgd switch (flags & O_ACCMODE) { 139 1.5.2.2 cgd case O_RDONLY: 140 1.5.2.2 cgd SET(t, R_RDONLY); 141 1.5.2.2 cgd break; 142 1.5.2.2 cgd case O_RDWR: 143 1.5.2.2 cgd break; 144 1.5.2.2 cgd default: 145 1.5.2.2 cgd goto einval; 146 1.5.2.2 cgd } 147 1.5.2.2 cgd 148 1.5.2.2 cgd if (fstat(rfd, &sb)) 149 1.5.2.2 cgd goto err; 150 1.5.2.2 cgd /* 151 1.5.2.2 cgd * Kluge -- we'd like to test to see if the file is too 152 1.5.2.2 cgd * big to mmap. Since, we don't know what size or type 153 1.5.2.2 cgd * off_t's or size_t's are, what the largest unsigned 154 1.5.2.2 cgd * integral type is, or what random insanity the local 155 1.5.2.2 cgd * C compiler will perpetrate, doing the comparison in 156 1.5.2.2 cgd * a portable way is flatly impossible. Hope that mmap 157 1.5.2.2 cgd * fails if the file is too large. 158 1.5.2.2 cgd */ 159 1.5.2.2 cgd if (sb.st_size == 0) 160 1.5.2.2 cgd SET(t, R_EOF); 161 1.5.2.2 cgd else { 162 1.5.2.2 cgd t->bt_msize = sb.st_size; 163 1.5.2.2 cgd if ((t->bt_smap = mmap(NULL, t->bt_msize, 164 1.5.2.2 cgd PROT_READ, MAP_PRIVATE, rfd, 165 1.5.2.2 cgd (off_t)0)) == (caddr_t)-1) 166 1.5.2.2 cgd goto slow; 167 1.5.2.2 cgd t->bt_cmap = t->bt_smap; 168 1.5.2.2 cgd t->bt_emap = t->bt_smap + sb.st_size; 169 1.5.2.2 cgd t->bt_irec = ISSET(t, R_FIXLEN) ? 170 1.5.2.2 cgd __rec_fmap : __rec_vmap; 171 1.5.2.2 cgd SET(t, R_MEMMAPPED); 172 1.5.2.2 cgd } 173 1.5.2.2 cgd } 174 1.5.2.2 cgd } 175 1.5.2.2 cgd 176 1.5.2.2 cgd /* Use the recno routines. */ 177 1.5.2.2 cgd dbp->close = __rec_close; 178 1.5.2.2 cgd dbp->del = __rec_delete; 179 1.5.2.2 cgd dbp->fd = __rec_fd; 180 1.5.2.2 cgd dbp->get = __rec_get; 181 1.5.2.2 cgd dbp->put = __rec_put; 182 1.5.2.2 cgd dbp->seq = __rec_seq; 183 1.5.2.2 cgd dbp->sync = __rec_sync; 184 1.5.2.2 cgd 185 1.5.2.2 cgd /* If the root page was created, reset the flags. */ 186 1.5.2.2 cgd if ((h = mpool_get(t->bt_mp, P_ROOT, 0)) == NULL) 187 1.5.2.2 cgd goto err; 188 1.5.2.2 cgd if ((h->flags & P_TYPE) == P_BLEAF) { 189 1.5.2.2 cgd h->flags = h->flags & ~P_TYPE | P_RLEAF; 190 1.5.2.2 cgd mpool_put(t->bt_mp, h, MPOOL_DIRTY); 191 1.5.2.2 cgd } else 192 1.5.2.2 cgd mpool_put(t->bt_mp, h, 0); 193 1.5.2.2 cgd 194 1.5.2.2 cgd if (openinfo && openinfo->flags & R_SNAPSHOT && 195 1.5.2.2 cgd !ISSET(t, R_EOF | R_INMEM) && 196 1.5.2.2 cgd t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR) 197 1.5.2.2 cgd goto err; 198 1.5.2.2 cgd return (dbp); 199 1.5.2.2 cgd 200 1.5.2.2 cgd einval: errno = EINVAL; 201 1.5.2.2 cgd err: sverrno = errno; 202 1.5.2.2 cgd if (dbp != NULL) 203 1.5.2.2 cgd (void)__bt_close(dbp); 204 1.5.2.2 cgd if (fname != NULL) 205 1.5.2.2 cgd (void)close(rfd); 206 1.5.2.2 cgd errno = sverrno; 207 1.5.2.2 cgd return (NULL); 208 1.5.2.2 cgd } 209 1.5.2.2 cgd 210 1.5.2.2 cgd int 211 1.5.2.2 cgd __rec_fd(dbp) 212 1.5.2.2 cgd const DB *dbp; 213 1.5.2.2 cgd { 214 1.5.2.2 cgd BTREE *t; 215 1.5.2.2 cgd 216 1.5.2.2 cgd t = dbp->internal; 217 1.5.2.2 cgd 218 1.5.2.2 cgd /* Toss any page pinned across calls. */ 219 1.5.2.2 cgd if (t->bt_pinned != NULL) { 220 1.5.2.2 cgd mpool_put(t->bt_mp, t->bt_pinned, 0); 221 1.5.2.2 cgd t->bt_pinned = NULL; 222 1.5.2.2 cgd } 223 1.5.2.2 cgd 224 1.5.2.2 cgd /* In-memory database can't have a file descriptor. */ 225 1.5.2.2 cgd if (ISSET(t, R_INMEM)) { 226 1.5.2.2 cgd errno = ENOENT; 227 1.5.2.2 cgd return (-1); 228 1.5.2.2 cgd } 229 1.5.2.2 cgd return (t->bt_rfd); 230 1.5.2.2 cgd } 231
Indexes created Sun Oct 12 02:09:55 GMT 2025