1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Mike Olson. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #if defined(LIBC_SCCS) && !defined(lint) 36 static char sccsid[] = "@(#)rec_open.c 8.10 (Berkeley) 9/1/94"; 37 #endif /* LIBC_SCCS and not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include "namespace.h" 42 #include <sys/types.h> 43 #include <sys/mman.h> 44 #include <sys/stat.h> 45 46 #include <errno.h> 47 #include <fcntl.h> 48 #include <limits.h> 49 #include <stddef.h> 50 #include <stdio.h> 51 #include <unistd.h> 52 #include "un-namespace.h" 53 54 #include <db.h> 55 #include "recno.h" 56 57 DB * 58 __rec_open(const char *fname, int flags, int mode, const RECNOINFO *openinfo, 59 int dflags) 60 { 61 BTREE *t; 62 BTREEINFO btopeninfo; 63 DB *dbp; 64 PAGE *h; 65 struct stat sb; 66 int rfd, sverrno; 67 68 /* Open the user's file -- if this fails, we're done. */ 69 if (fname != NULL && (rfd = _open(fname, flags | O_CLOEXEC, 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 = 135 F_ISSET(t, R_FIXLEN) ? __rec_fpipe : __rec_vpipe; 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) ? 177 __rec_fmap : __rec_vmap; 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 222 __rec_fd(const DB *dbp) 223 { 224 BTREE *t; 225 226 t = dbp->internal; 227 228 /* Toss any page pinned across calls. */ 229 if (t->bt_pinned != NULL) { 230 mpool_put(t->bt_mp, t->bt_pinned, 0); 231 t->bt_pinned = NULL; 232 } 233 234 /* In-memory database can't have a file descriptor. */ 235 if (F_ISSET(t, R_INMEM)) { 236 errno = ENOENT; 237 return (-1); 238 } 239 return (t->bt_rfd); 240 } 241